Substrate processing system and device manufacturing method

Abstract

A measurement system (500) for a microcomponent production line is provided with: a plurality of measurement devices (1001-1003) that respectively perform measurement processing on a substrate; and a control device (530) that can control the plurality of measurement devices. The plurality of measurement devices (1001-1003) include at least one first measurement device that acquires position information of a plurality of marks formed on the substrate.

Description

[0001] This case is a divisional application of the invention patent application with the original application number 201780065873.2, international application number PCT / JP2017 / 029854, application date August 22, 2017, and invention name "Measurement system and substrate processing system, and component manufacturing method". Technical Field

[0002] The present invention relates to a measuring system, a substrate processing system, and a component manufacturing method. More specifically, the present invention relates to a measuring system for a micro-component production line, a substrate processing system including the measuring system, and a component manufacturing method using an exposure device that constitutes a part of the substrate processing system. Background Art

[0003] In the lithography step of manufacturing micro-components such as semiconductor components, a multi-layer circuit pattern is formed by stacking on a substrate such as a wafer or a glass plate (hereinafter collectively referred to as a wafer). However, if the stacking accuracy between the layers is poor, the micro-component cannot exhibit the predetermined circuit characteristics and may become a defective product depending on the circumstances. Therefore, usually, marks (alignment marks) are formed in advance on multiple shot areas (shots) on the wafer, and the positions (coordinate values) of the marks on the stage coordinate system of the exposure device are detected. Then, based on the position information of the marks and the known position information of the newly formed pattern (such as a reticle pattern), wafer alignment is performed to align one shot area on the wafer with respect to the pattern.

[0004] As a method of wafer alignment, based on the consideration of throughput, enhanced global alignment (EGA) has become the mainstream method, which only detects the alignment marks of several irradiation areas (also called sampling irradiation areas or alignment irradiation areas) on the wafer and calculates the arrangement of the irradiation areas on the wafer by statistical methods.

[0005] However, in the case of performing overlapping exposure on a wafer in the lithography step, the arrangement of the irradiation area of ​​the front layer may be deformed due to the process on the wafer after the process steps such as resist coating, development, etching, CVD (chemical vapor deposition), CMP (chemical mechanical polishing), etc., and this deformation may become a factor that reduces the overlapping accuracy. In view of this, recent exposure devices not only correct the primary component of wafer deformation, but also have a grid correction function that corrects the nonlinear component of the arrangement of the irradiation area caused by the process (for example, refer to Patent Document 1).

[0006] However, with the miniaturization of integrated circuits, the requirements for overlay accuracy have become increasingly stringent. In order to perform corrections with higher accuracy, it is essential to increase the number of sample irradiation areas, that is, to increase the number of marks to be detected. In addition, in a dual-stage exposure device having two stages for mounting wafers, it is possible to perform mark detection on a wafer on the other stage while exposing the wafer on one stage, so that the number of sample irradiation areas can be increased as little as possible without reducing the output.

[0007] However, today, the requirements for overlay accuracy have become more stringent, and even with a dual-stage exposure apparatus, it is difficult to detect a sufficient number of marks to achieve the required overlay accuracy without reducing throughput.

[0008] Prior art literature

[0009] Patent Literature

[0010] Patent Document 1: U.S. Patent Application Publication No. 2002 / 0042664 Summary of the invention

[0011] [Methods to solve the problem]

[0012] According to the first form, a measurement system is provided, which is a production line for microcomponents and comprises: a plurality of measuring devices, which respectively perform measurement processing on a substrate; and a control device, which can control the plurality of measuring devices, wherein the plurality of measuring devices include at least one first measuring device for obtaining position information of a plurality of marks formed on the substrate.

[0013] According to the second aspect, a measuring system is provided, which is used for a production line of microcomponents and comprises: a first measuring device, which obtains position information of a plurality of marks formed on a substrate; and a control device, which can control the first measuring device, wherein the first measuring device obtains position information of a plurality of marks formed on a substrate subjected to exposure and development treatment.

[0014] According to the third aspect, a measuring system is provided, which is used for a production line of microcomponents and comprises: a first measuring device, which obtains position information of a plurality of marks formed on a substrate; and a control device, which can control the first measuring device, wherein the first measuring device obtains position information of a plurality of marks formed on the substrate after etching and film forming and before coating with a photosensitive material.

[0015] According to the fourth aspect, a substrate processing system is provided, which comprises: a measurement system of the third aspect; and an exposure device, which has a substrate carrier, the substrate being loaded with the substrate after the measurement of the position information of the plurality of marks by the first measurement device included in the measurement system is completed, for the substrate loaded on the substrate carrier, alignment measurement is performed to obtain the position information of a portion of marks selected from the plurality of marks on the substrate, and the substrate is exposed using an energy beam.

[0016] According to the fifth aspect, a substrate processing system is provided, comprising: any one of the measurement system of the first aspect and the measurement system of the second aspect; and an exposure device having a substrate carrier, the substrate being mounted on which the measurement of the position information of the plurality of marks by the first measurement device included in the measurement system is completed; for the substrate mounted on the substrate carrier, alignment measurement is performed to obtain the position information of a portion of marks selected from the plurality of marks on the substrate, and the substrate is exposed using an energy beam.

[0017] According to a sixth aspect, there is provided a device manufacturing method, comprising: exposing a substrate using an exposure device constituting a part of either the substrate processing system of the fourth aspect or the substrate processing system of the fifth aspect; and developing the exposed substrate. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is a block diagram showing the substrate processing system of the first embodiment together with other devices used in a micro-component production line;

[0019] Figure 2 Yes means Figure 1 A perspective view of the appearance of a measurement system provided in a substrate processing system;

[0020] Figure 3 It means that the ceiling of the chamber is removed. Figure 1 A top view of the measurement system;

[0021] Figure 4 This is a perspective view schematically showing the configuration of a measuring device constituting a part of a measuring system;

[0022] Figure 5(A) is Figure 4 FIG5(B) is a partially omitted front view of the measuring device (viewed from the -Y direction), and FIG5(B) is a partially omitted sectional view of the measuring device cut along an XZ plane passing through the optical axis AX1 of the mark detection system;

[0023] Figure 6 A partially omitted cross-sectional view of the measuring device cut along a YZ plane passing through the optical axis AX1 of the mark detection system;

[0024] 7(A) is a perspective view showing a head section of a first position measuring system, and FIG. 7(B) is a top view (viewed from the +Z direction) of the head section of the first position measuring system;

[0025] Figure 8 is a diagram for explaining the configuration of a second position measurement system;

[0026] Fig. 9 is a block diagram showing the input / output relationship of a control device which mainly constitutes a control system of a measuring device;

[0027] Fig.10 is a flowchart corresponding to a processing algorithm of a control device when processing one batch of wafers;

[0028] Fig.11 It roughly indicates Figure 1 A diagram showing the structure of an exposure device.

[0029] Fig.12 is a block diagram showing the input / output relationship of an exposure control device provided in the exposure device;

[0030] FIG. 13(A) is a diagram for explaining an example of a high-order partial differential correction, and FIG. 13(B) is a diagram for explaining an example of a first-order approximate correction;

[0031] Fig.14 The second embodiment schematically shows a method for managing a wafer grid of an exposure device using a measuring device. Figure 1 A diagram of a processing flow in the case of a substrate processing system;

[0032] Fig.15 This is a schematic diagram showing the application of the superposition measurement method using the measurement device of the second embodiment to Figure 1 A diagram of a processing flow in the case of a substrate processing system;

[0033] Fig.16 This is a diagram showing an example of a manufacturing process of a semiconductor element. DETAILED DESCRIPTION

[0034] 《First Implementation Form》

[0035] The following is based on Figure 1 to Figure 13 (B) The first embodiment will be described. Figure 1 In the figure, a substrate processing system 1000 according to a first embodiment used in a production line for micro devices (eg, semiconductor devices) is shown in a block diagram together with other devices used in the production line.

[0036] The substrate processing system 1000 is as follows Figure 1As shown in FIG. 1 , the substrate processing system 1000 includes an exposure device 200 and a coating and developing machine (resist coating and developing device) 300 connected in an online manner. Figure 1 As shown, it is equipped with a measurement system 500. Hereinafter, the coating and developing machine 300 is referred to as C / D 300. Furthermore, the so-called online connection refers to that different devices are connected to each other in a manner that the conveying paths of the wafers (substrates) are substantially connected. In this specification, the terms "online connection" or "online connection" are used in this sense. For example, when two different devices are connected online, a conveying mechanism such as a robot arm can be used to sequentially convey the wafer (substrate) processed in one of the devices to the other device. Furthermore, the situation where different devices are connected through an interface is sometimes referred to as "online connection".

[0037] Here, the measurement system 500 is provided in the same chamber 502 (see Figure 2 ) are arranged adjacent to each other in a predetermined direction, and a measurement system control device 530 for centrally managing the entire measurement system 500. Each of the measurement devices 1001 to 1003 has a control device 60 i (i=1-3), control device 60 i Each is connected to the measurement system control device 530. Furthermore, the control device 60 may not be provided. i (i=1 to 3), and the measurement system control device 530 controls each of the measurement devices 1001 to 1003.

[0038] The exposure device 200 and the C / D 300 included in the substrate processing system 1000 both have chambers, and the chambers are arranged adjacent to each other.

[0039] The exposure control device 220 of the exposure device 200, the C / D control device 320 of the C / D 300, and the measurement system control device 530 are connected to each other via a local area network (LAN) 1500. The LAN 1500 is also connected to a host computer (HOST) 2000 that manages the entire production line, an analysis device 3000, and a device group that performs various process processing (process processing in the pre-step of the wafer process) under the management of the host computer 2000. Figure 1 1, the device group includes a superposition measuring device 400, an etching device 2100, a CMP device 2200, and a film forming device 2300 such as a CVD device. In addition, a cleaning device, an oxidation / diffusion device, an ion implantation device, and the like are connected to the LAN 1500.

[0040] Furthermore, the substrate processing system 1000 may also include at least one of a host computer 2000 , an analysis device 3000 , an overlay measurement device 400 , an etching device 2100 , a CMP device 2200 , and a film forming device 2300 .

[0041] First, the measurement system 500 will be described. Figure 2 The external perspective view of the measurement system 500 is shown. The measurement system 500 is installed on the floor F of the clean room separately from other devices constituting the substrate processing system 1000. That is, the measurement system 500 is not connected inline with the exposure device 200 and the C / D 300.

[0042] The measurement system 500 includes: a chamber 502 in which the three measurement devices 1001 to 1003 are arranged; and a carrier system 510 arranged at one side of the chamber 502. In this embodiment, the carrier system 510 is an EFEM (Equipment Front End Module) system. Hereinafter, the carrier system 510 may also be referred to as the EFEM system 510.

[0043] Furthermore, as described later, the carrier system 510 of this embodiment is for FOUP (Front-Opening Unified Pod), but is not limited to FOUP. Other types of carriers (such as SMIF pods) that can accommodate one or more wafers can also be processed by the carrier system 510.

[0044] In the following description, the arrangement direction of the chamber 502 and the EFEM system 510 is assumed to be the X-axis direction, the direction perpendicular to the X-axis in a plane parallel to the ground F is assumed to be the Y-axis direction, and the direction orthogonal to the X-axis and the Y-axis is assumed to be the Z-axis direction.

[0045] like Figure 2 As shown, the chamber 502 has a rectangular parallelepiped shape, and the first space inside it is as shown in FIG. Figure 3 As shown, measuring devices 1001 to 1003 are stored in a row along the X-axis direction. Figure 3 A top view of the measurement system 500 is shown with the ceiling portion of the chamber 502 removed. Figure 3 , the chamber 101 of each of the measuring devices 1001 to 1003 is shown. i (i=1 to 3). Furthermore, the measuring devices 1001 to 1003 may not each include the chamber 101. i .

[0046] In the measurement system 500, since the plurality of measurement devices 1001 to 1003 are arranged in the X-axis direction, the plurality of measurement devices 1001 to 1003 can be provided without increasing the width of the measurement system 500 in the Y-axis direction. In a factory where the measurement system 500 and the like are installed, a passage for operators extends in the Y-axis direction, and the devices (etching device 2100, CMP device 2200, etc.) for performing the above-mentioned various processes are arranged along the passage. Therefore, in order to effectively utilize the floor F of the factory, it is important to suppress the width of the measurement system 500 in the Y-axis direction.

[0047] Furthermore, a transfer system 521 is disposed on the -Y side of the first space in the chamber 502, and the transfer system 521 can transport wafers together with the measurement devices 1001 to 1003. In the following, for convenience, the space on the -Y side of the first space where the transfer system 521 is disposed is referred to as the second space. Figure 2 In FIG. 1 , the thick dotted line represents an imaginary partition between the first space and the second space.

[0048] An EFEM system 510 is installed on the floor F adjacent to the -X side (front side) of the chamber 502. The EFEM system 510 is a modular machine having an EFEM body 512 and a load port. The EFEM body 512 has a wafer transfer robot installed inside, and the load port is installed on the -X side (front side) of the EFEM body 512. On the EFEM body 512, on the front side thereof, a plurality of load ports 514 (also referred to as a carrier loading device) for FOUP are arranged along the Y-axis direction. In the present embodiment, the EFEM body 512 has three load ports 514, but the number of the load ports is not limited to three, and may be one, two, four or more. Here, the so-called FOUP refers to a carrier for transporting and storing wafers used in a semiconductor factory of a mini-environment system specified in SEMI standard E47.1, and is a front-opening cassette-integrated transport and storage box. Figure 2 and Figure 3 In the embodiment, a FOUP 520 is disposed on each of the three load ports 514, and at least one wafer is accommodated in the FOUP as a measurement object.

[0049] Although not shown in the figure in this embodiment, a track guide for OHT (Overhead Hoist Transport) is provided near the ceiling of the clean room directly above the three load ports 514. The OHT is an unmanned transport vehicle that moves in the space at the ceiling level, and the FOUP 520 is transported to the load port 514 by the OHT.

[0050] Each of the three loading ports 514 has a loading portion 515 and an opening and closing mechanism 518 for opening and closing the cover of the FOUP 520 loaded on the loading portion 515. The opening and closing mechanism 518 is provided at the front side portion of the EFEM body 512 facing the FOUP 520 loaded on the loading portion 515 of the loading port 514, and can open and close the cover of the FOUP 520 while keeping the inside of the FOUP 520 airtight from the outside. Such an opening and closing mechanism is well known, and therefore the description of the structure of the opening and closing mechanism 518 is omitted.

[0051] Inside the EFEM body 512, there is provided a wafer transfer robot 516 (see Figure 3 ) to take out / put in the wafer. Furthermore, an FFU (FanFilter Unit, not shown) for maintaining the cleanliness of the inside of the EFEM body 512 may be provided on the upper part of the EFEM body 512, and the temperature-controlled air from the air conditioner is sent to the inside of the EFEM body 512 through the FFU. Furthermore, a buffer part that uses the temperature-controlled air from the air conditioner to stabilize the temperature of the wafer may be provided inside the EFEM body 512.

[0052] An opening is formed at a portion on the back side of the EFEM body 512 that faces the second space of the chamber 502 , and the opening is opened and closed by an opening and closing member.

[0053] Each component of the EFEM system 510 (robot 516, opening and closing mechanism 518, etc.) is controlled by a measurement system control device 530 (see Figure 1 ) to be controlled.

[0054] In the second space of the chamber 502, as Figure 3 As shown, a conveying system 521 is provided. It is provided with: guide rails 522A and 522B, which are respectively arranged on one side and the other side of the Y-axis direction in the second space and extend along the X-axis direction over the substantially entire length of the chamber 502; a loading conveying member 524, which can reciprocate along the guide rail 522A; and an unloading conveying member 526, which can reciprocate along the guide rail 522B.

[0055] The loading conveying member 524 can be moved along the guide rail 522A by a linear motor (expressed as a linear motor 522A using the same symbol as the guide rail with a built-in fixed part) having a fixed part built in the guide rail 522A and a movable part provided in the conveying member 524. In addition, the unloading conveying member 526 can be moved along the guide rail 522B by a linear motor (expressed as a linear motor 522B using the same symbol as the guide rail with a built-in fixed part) having a fixed part built in the guide rail 522B and a movable part provided in the conveying member 526. The linear motors 522A and 522B are controlled by the measurement system control device 530. Furthermore, the conveying members 524 and 526 can also be moved in a non-contact manner using a pneumatic slide or the like. Furthermore, the driving mechanism for driving the conveying members 524 and 526 is not limited to the above-mentioned linear motors ( 522A and 522B), and may be a structure using a rotary motor and a ball screw mechanism.

[0056] The guide rail 522A is arranged at a higher position than the guide rail 522B. Therefore, the loading conveying member 524 moves in the space above the unloading conveying member 526.

[0057] Furthermore, in the above-mentioned transport system 521, the transport member 524 and the guide rail 522A can be used for loading and unloading of wafers, and the transport member 526 and the guide rail 522B can be used for loading and unloading of wafers.

[0058] Furthermore, the transport system 521 can transport wafers with the plurality of measuring devices 1001 to 1003, respectively. However, the transport system 521 may include a transport device (including a guide rail and a transport member) that transports wafers with the measuring device 1001 only, a transport device (including a guide rail and a transport member) that transports wafers with the measuring device 1002 only, and a transport device (including a guide rail and a transport member) that transports wafers with the measuring device 1003 only. In this case, the transport device may include a guide rail and a transport member for loading, and a guide rail and a transport member for unloading, respectively, or a guide rail and a transport member that are used for both loading and unloading.

[0059] like Figure 3 As shown, in the measuring device 100 i There is a wafer transfer system 70 i (i=1-3), the wafer transfer system 70 i (i=1 to 3) A multi-jointed robot is provided for transferring wafers between the transfer member 524 and the transfer member 526. Wafer transfer system 70 i (i=1-3) through chamber 101 i The wafer is transported between the conveying member 524 and the conveying member 526 through the opening.

[0060] The transfer member 524 receives the wafer to be measured in the FOUP 520 from the robot 516 at a wafer transfer position (load side wafer transfer position) set near the boundary between the EFEM body 512 and the chamber 502, and transfers it to the wafer transfer system 70. i (i=any one of 1 to 3) and the measuring device 100 i In this embodiment, the wafer to be measured is a wafer that has been subjected to at least the first layer of exposure, and further to the development, and has been subjected to the necessary processing in the process processing of the previous steps of the wafer process such as etching, oxidation / diffusion, film formation, ion implantation, and planarization (CMP), and is a wafer before being moved into C / D300 for the purpose of resist coating.

[0061] The transport member 526 is from the wafer transport system 70 i (i=any one of 1 to 3) The wafer after measurement is received and transported to an unloading side wafer transfer position (a position below the aforementioned loading side wafer transfer position) set near the boundary between the EFEM body 512 and the chamber 502 .

[0062] The robot 516 carries (returns) the wafers that have been subjected to the measurement process and that have been transported to the unloading-side wafer transfer position by the transport member 526 into the FOUP 520 .

[0063] return Figure 1 In this embodiment, as each of the measuring devices 1001 to 1003, a measuring device having the same structure is used.

[0064] In addition, in this embodiment, the following case is illustrated, that is, the conveying member 524, the conveying member 526, etc. are used for the measurement device 100 i The transport system 521 for wafer transportation is arranged in the second space of the chamber 502, so that the space for transporting wafers by means of the transport components 524 and 526 eventually becomes an airtight space, but it is not limited to this. The three measuring devices 1001~1003 can also be arranged on the ground F, and other chambers are set in the measuring devices 1001~1003 (regardless of whether they are accommodated in the same chamber) to form an airtight chamber inside which the transport system 521 is accommodated.

[0065] Furthermore, a multi-jointed robot that can reciprocate along the guide rails may be used in place of the conveying members 524 and 526. i The multi-articulated robot need not be provided, and it is sufficient to provide a loading wafer holding unit and an unloading wafer holding unit that perform wafer transfer with the multi-articulated robot of the transfer system 521 .

[0066] Furthermore, when an articulated robot is used instead of the conveying members 524 and 526 , the EFEM system 510 may not include the robot 516 . In this case, the articulated robot of the conveying system 521 may take out the wafer from the FOUP 520 or return the wafer to the FOUP 520 .

[0067] Here, the measuring device 100 i Describe in detail. Figure 4 In FIG. 1 , the measuring device 100 is schematically shown in a perspective view. i Furthermore, Figure 4 The measuring device 100 shown i In fact, it includes the aforementioned chamber 101 i and contained in the chamber 101 i The internal components of the chamber 101 are omitted below. i The measuring device 100 of this embodiment i In the figure, a mark detection system MDS is provided as described later. In the following, it is assumed that the direction of the optical axis AX1 of the mark detection system MDS is consistent with the aforementioned Z-axis direction, and in the XY plane orthogonal thereto, the direction in which the movable stage described later moves with a long stroke is consistent with the aforementioned Y-axis direction, and the rotation (tilt) directions around the X-axis, Y-axis, and Z-axis are θx, θy, and θz directions, respectively, for explanation. Here, the mark detection system MDS is provided with a cylindrical lens barrel portion 41 at its lower end (front end), and an optical system (refractive optical system) is accommodated inside the lens barrel portion 41. The optical system (refractive optical system) includes a plurality of lens elements having a common optical axis AX1 in the Z-axis direction. In this specification, for the sake of convenience, the optical axis AX1 of the refractive optical system inside the lens barrel portion 41 is referred to as the optical axis AX1 of the mark detection system MDS.

[0068] In FIG. 5(A), part of the Figure 4 Measuring device 100 i 5(B) shows a partially omitted measurement device 100 cut along an XZ plane passing through the optical axis AX1. i A cross-sectional view of Figure 6 In the figure, the measuring device 100 cut along the YZ plane passing through the optical axis AX1 is partially omitted. i Cross-sectional view of .

[0069] Measuring device 100 i like Figure 4As shown, it comprises: a platen 12 having an upper surface substantially parallel to an XY plane orthogonal to the optical axis AX1; a wafer slider (hereinafter referred to as a slider) 10, which is arranged on the platen 12, holds a wafer W and is movable relative to the platen 12 along the X-axis and Y-axis directions with a predetermined stroke, and can move slightly (micro displacement) in the Z-axis, θx, θy and θz directions; a drive system 20 (refer to Fig. 9 ), which drives the slide 10; the first position measurement system 30 ( Figure 4 Not shown in the figure, refer to Figure 6 , Fig. 9 ), which measures the position information of the slide 10 relative to the fixed plate 12 in each direction of the X-axis, Y-axis, Z-axis, θx, θy and θz (hereinafter referred to as the 6-DOF direction); a measuring unit 40, which has a mark detection system MDS for detecting a mark on the wafer W mounted (held) on the slide 10; a second position measurement system 50 (refer to Fig. 9 ), which measures the relative position information between the mark detection system MDS (measuring unit 40) and the fixed plate 12; and the control device 60 i ( Figure 4 Not shown in the figure, refer to Fig. 9 ) which controls the driving of the slide 10 by the driving system 20, obtains the measurement information of the first position measurement system 30 and the measurement information of the second position measurement system 50, and uses the mark detection system MDS to obtain the position information of multiple marks on the wafer W held on the slide 10.

[0070] The fixed plate 12 is composed of a rectangular (or square) parallelepiped member in a top view, and its upper surface is finished in a manner to have a very high flatness, forming a guide surface when the slider 10 moves. As the material of the fixed plate 12, a low thermal expansion material also called a zero expansion material is used, such as an Invar alloy, an ultra-low expansion cast steel, or an ultra-low expansion glass ceramic.

[0071] On the surface plate 12, three cavities 12a with cutouts having open bottoms are formed, one at the center of the surface on the -Y side in the X-axis direction and one at each of the two ends of the surface on the +Y side in the X-axis direction. Figure 4 , a cavity 12a formed on the -Y side of the three cavities 12a is shown. A vibration isolating device 14 is disposed inside each cavity 12a. The fixed plate 12 is supported at three points by three vibration isolating devices 14 on the upper surface of a rectangular base frame 16 in a plan view and parallel to the XY plane, which is set on the ground F, in such a manner that the upper surface is substantially parallel to the XY plane. The number of vibration isolating devices 14 is not limited to three.

[0072] Slider 10 Figure 6As shown, four air static pressure bearings (air bearings) 18 are installed at four corners of the bottom surface, one each, in a state where the bearing surfaces of the respective bearings are substantially flush with the bottom surface of the slider 10. The slider 10 is suspended and supported on the top surface of the top surface of the top plate 12 through a predetermined clearance (gap, gap), for example, a clearance of about several μm, by the static pressure (pressure in the gap) between the bearing surfaces of the pressurized air ejected from the four air bearings 18 toward the top plate 12 and the top surface (guide surface) of the top plate 12. In the present embodiment, the slider 10 is made of zero expansion glass (e.g., Zerodur of Schott Co., Ltd.), which is a type of zero expansion material.

[0073] A recess 10a of a predetermined depth in a circular shape with an inner diameter slightly larger than the diameter of the wafer W when viewed from above is formed on the upper part of the slide 10, and a wafer holder WH having a diameter substantially the same as that of the wafer W is arranged inside the recess 10a. As the wafer holder WH, a vacuum clamp, an electrostatic clamp, or a mechanical clamp can be used. As an example, a vacuum clamp using a pin clamping method is used. The wafer W is held by adsorption by the wafer holder WH in a state where its upper surface is substantially flush with the upper surface of the slide 10. A plurality of suction ports are formed on the wafer holder WH, and the plurality of suction ports are connected to a vacuum pump 11 (see FIG. 1 ) via a vacuum piping system not shown in the figure. Fig. 9 ). In addition, the vacuum pump 11 is turned on / off by the control device 60. i In addition, either or both of the slider 10 and the wafer holder WH may be referred to as a "first substrate holding member".

[0074] Furthermore, a vertical moving member (not shown) is provided on the slider 10. The vertical moving member moves up and down through, for example, three circular openings formed on the wafer holder WH and is connected to the wafer transfer system 70. i ( Figure 4 Not shown in the figure, refer to Fig. 9 ) cooperates to load the wafer onto the wafer holder WH and unload the wafer from the wafer holder WH. The driving device 13 that drives the up and down moving member is controlled by the control device 60 i Control (see Fig. 9 ).

[0075] In this embodiment, as an example of a wafer holder WH, a wafer having a size capable of holding a 300 mm wafer having a diameter of 300 mm by suction is used. i In the case of a non-contact holding member such as a Bernoulli clamp that holds the wafer on the wafer holder WH by non-contact suction from above, there is no need to provide an up-and-down moving member on the slide 10, nor is there a circular opening for the up-and-down moving member formed on the wafer holder WH.

[0076] As shown in Figure 5(B) and Figure 6 As shown, a two-dimensional grating (hereinafter referred to as grating) RG1 is horizontally arranged (parallel to the surface of the wafer W) in an area of ​​the lower surface of the slider 10 that is one circle larger than the wafer W. The grating RG1 includes: a reflection type diffraction grating (X diffraction grating) with the X-axis direction as the periodic direction; and a reflection type diffraction grating (Y diffraction grating) with the Y-axis direction as the periodic direction. The spacing of the grating lines of the X diffraction grating and the Y diffraction grating is set to 1μm, for example.

[0077] The vibration isolation device 14 is an active vibration isolation system (so-called AVIS (Active Vibration Isolation System)), which includes an accelerometer, a displacement sensor (such as an electrostatic capacitance sensor, etc.), an actuator (such as a voice coil motor, etc.), and an air shock absorber that functions as an air damper. The vibration isolation device 14 can attenuate relatively high-frequency vibrations by means of the air shock absorber (air damper), and can perform vibration isolation (vibration reduction) by means of the actuator. Therefore, the vibration isolation device 14 can prevent vibrations from being transmitted between the fixed plate 12 and the base frame 16. Furthermore, a hydraulic damper can be used instead of the air shock absorber (air damper).

[0078] Here, the actuator is provided in addition to the air shock absorber because the gas pressure in the air chamber of the air shock absorber is high and the control response can only be ensured to be around 20Hz. Therefore, when high-response control is required, the actuator must be controlled based on the output of an accelerometer, etc., which is not shown. However, micro-vibrations such as floor vibrations can be eliminated by air shock absorbers.

[0079] The upper end surface of the vibration isolation device 14 is connected to the fixed plate 12. For the air shock absorber, gas (for example, compressed air) can be supplied through a gas supply port not shown in the figure, and the air shock absorber expands and contracts in the Z-axis direction with a predetermined stroke (for example, about 1 mm) according to the amount of gas filled inside (pressure change of the compressed air). Therefore, by using the air shock absorbers of each of the three vibration isolation devices 14, the three locations of the fixed plate 12 are moved up and down individually from the bottom, so that the positions of the fixed plate 12 and the slider 10 suspended and supported thereon in the Z-axis direction, the θx direction, and the θy direction can be arbitrarily adjusted. In addition, the actuator of the vibration isolation device 14 drives the fixed plate 12 not only in the Z-axis direction, but also in the X-axis direction and the Y-axis direction. Furthermore, the drive amount in the X-axis direction and the Y-axis direction is smaller than the drive amount in the Z-axis direction. The three vibration isolation devices 14 are connected to the control device 60. i (Refer to Fig. 9 ). Furthermore, the three vibration isolating devices 14 are not limited to the X-axis direction, the Y-axis direction, and the Z-axis direction, and may include, for example, an actuator that moves the platen 12 in six directions of freedom. iBased on the relative position information between the mark detection system MDS (measurement unit 40) and the platen 12 measured by the second position measurement system 50, the actuators of the three vibration isolation devices 14 are always controlled in real time so that the position of the platen 12 in the 6-DOF direction fixed by the head unit 32 of the first position measurement system 30 described later maintains a desired positional relationship with respect to the mark detection system MDS. Furthermore, the three vibration isolation devices 14 can also be feedforward controlled individually. For example, the control device 60 i It is also possible to perform feedforward control on each of the three vibration isolating devices 14 based on the measurement information of the first position measurement system 30. i The control of the vibration isolation device 14 will be described further later.

[0080] The drive system 20 is as follows Fig. 9 As shown, the first drive device 20A for driving the slider 10 in the X-axis direction and the second drive device 20B for driving the slider 10 in the Y-axis direction are provided integrally with the first drive device 20A.

[0081] Depend on Figure 4 and Figure 6 It can be seen that on the side surface of the -Y side of the slider 10, a pair of movable members 22a are fixed at a predetermined interval along the X-axis direction. The pair of movable members 22a are composed of magnet units (or coil units) and are in an inverted L shape when viewed from the side. Figure 6 As shown, a pair of movable elements 22b composed of magnet units (or coil units) are fixed at a predetermined interval along the X-axis direction (but the movable element 22b on the +X side is not shown). The pair of movable elements 22a and the pair of movable elements 22b are arranged symmetrically, but have the same structure as each other.

[0082] The movable members 22a and 22b are as follows Figures 4 to 6 As shown, the movable members 22a and 22b are supported in a non-contact manner on the upper surfaces of a pair of plate members 24a and 24b substantially parallel to the XY plane. The pair of plate members 24a and 24b constitute a part of the movable stage 24 in a rectangular frame shape in a top view and are arranged at a predetermined distance in the Y-axis direction and extend in the X-axis direction. That is, air bearings (not shown) are provided on the lower surfaces of the movable members 22a and 22b (the surfaces facing the plate members 24a and 24b, respectively), and the movable members 22a and 22b are supported in a non-contact manner from below by the movable stage 24 by the suspension force (static pressure of pressurized air) generated by the air bearings relative to the plate members 24a and 24b. Furthermore, the weight of the slider 10 to which the pair of movable members 22a and 22b are fixed is supported by the suspension force generated by the four air bearings 18 relative to the fixed plate 12 as described above.

[0083] On the upper surface of each of the pair of plate members 24a, 24b, as shown Figures 4 to 6As shown, stators 26a and 26b composed of coil units (or magnet units) are arranged in the region excluding both ends in the X-axis direction.

[0084] By electromagnetic interaction between a pair of movable members 22a and a fixed member 26a, a driving force (electromagnetic force) for driving the pair of movable members 22a in the X-axis direction and a driving force (electromagnetic force) for driving the pair of movable members 22a in the Y-axis direction are generated. By electromagnetic interaction between a pair of movable members 22b and a fixed member 26b, a driving force (electromagnetic force) for driving the pair of movable members 22b in the X-axis direction and a driving force (electromagnetic force) for driving the pair of movable members 22b in the Y-axis direction are generated. That is, an XY linear motor 28A for generating driving forces in the X-axis direction and the Y-axis direction is formed by a pair of movable members 22a and a fixed member 26a, an XY linear motor 28B for generating driving forces in the X-axis direction and the Y-axis direction is formed by a pair of movable members 22b and a fixed member 26b, and a first driving device 20A (refer to FIG. 2 ) for driving the slide 10 in the X-axis direction at a predetermined stroke and performing a slight drive in the Y-axis direction is formed by the XY linear motor 28A and the XY linear motor 28B. Fig. 9 The first drive device 20A can drive the slide 10 in the θz direction by making the magnitude of the driving force in the X-axis direction generated by the XY linear motor 28A and the XY linear motor 28B different from each other. The first drive device 20A is controlled by the control device 60 i Control (see Fig. 9 In the present embodiment, the first drive device 20A and the second drive device described later together constitute a coarse and fine motion drive system for driving the slide 10 in the Y-axis direction. Based on this relationship, the first drive device 20A generates not only a driving force in the X-axis direction but also a driving force in the Y-axis direction. However, the first drive device 20A does not necessarily need to generate a driving force in the Y-axis direction.

[0085] The movable stage 24 has a pair of plate members 24a, 24b and a pair of connecting members 24c, 24d arranged at a predetermined distance in the X-axis direction and extending in the Y-axis direction. Steps are formed at both ends of the connecting members 24c, 24d in the Y-axis direction. In addition, when one end and the other end in the length direction of the plate member 24a are placed on the step on the -Y side of the connecting members 24c, 24d, the connecting members 24c, 24d are integrated with the plate member 24a. In addition, when one end and the other end in the length direction of the plate member 24b are placed on the step on the +Y side of the connecting members 24c, 24d, the connecting members 24c, 24d are integrated with the plate member 24b (refer to FIG. 5 (B)). That is, in this way, the pair of plate members 24a, 24b are connected by a pair of connecting members 24c, 24d to form a movable stage 24 in the shape of a rectangular frame.

[0086] like Figure 4As shown in FIG. 5(A), a pair of linear guides 27a and 27b extending in the Y-axis direction are fixed near both ends of the upper surface of the base frame 16 in the X-axis direction. Inside one of the linear guides 27a located on the +X side, near the upper surface and the surface on the -X side, a stator 25a (see FIG. 5(B)) of a Y-axis linear motor 29A composed of a coil unit (or a magnet unit) covering the substantially entire length in the Y-axis direction is accommodated. A movable member 23a is arranged facing the upper surface and the surface on the -X side of the linear guide 27a. The movable member 23a is composed of a magnet unit (or a coil unit) having an L-shaped cross section and constitutes the Y-axis linear motor 29A together with the stator 25a. Air bearings that spray pressurized air to the opposing surfaces are fixed to the lower surface and the surface on the +X side of the movable member 23a, which are respectively opposite to the upper surface and the surface on the -X side of the linear guide 27a. Among them, a vacuum preload type air bearing is used as the air bearing fixed to the +X side surface of the movable member 23a. The vacuum preload type air bearing maintains the clearance (gap, clearance) in the X-axis direction between the movable member 23a and the linear guide 27a at a fixed value by balancing the static pressure of the pressurized air between the bearing surface and the -X side surface of the linear guide 27a and the vacuum preload pressure.

[0087] On the upper surface of the movable member 23a, a plurality of, for example, two rectangular parallelepiped members, X rails 19, are fixed at predetermined intervals in the Y-axis direction. Sliding members 21 having an inverted U-shaped cross section are engaged with the two X rails 19 in a non-contact manner, and the sliding members 21 and the X rails 19 together constitute a single-axis rail device. Air bearings are provided on the three surfaces of the sliding members 21 facing the X rails 19.

[0088] Two sliding members 21 such as Figure 4 As shown, they are respectively fixed to the lower surface (surface on the -Z side) of the connecting member 24c.

[0089] Another linear guide 27b located on the -X side has a stator 25b of a Y-axis linear motor 29B composed of a coil unit (or magnet unit) stored inside, and is symmetrical with the linear guide 27a but has the same structure (see FIG5(B)). A movable member 23b is arranged facing the upper surface and the +X side surface of the linear guide 27b. The movable member 23b is symmetrical with the movable member 23a but is composed of a magnet unit (or coil unit) with the same L-shaped cross section, and together with the stator 25b, it constitutes the Y-axis linear motor 29B. Air bearings are fixed to the lower surface and the -X side surface of the movable member 23b, respectively, facing the upper surface and the +X side surface of the linear guide 27b. In particular, a vacuum preload type air bearing is used as the air bearing fixed to the -X side surface of the movable member 23b. The vacuum preload type air bearing maintains the clearance (gap, clearance) between the movable element 23 b and the linear guide 27 b in the X-axis direction at a constant value.

[0090] As described above, two uniaxial guide rail devices are provided between the upper surface of the movable member 23b and the bottom surface of the connecting member 24d. The uniaxial guide rail devices are composed of an X-guide rail 19 and a sliding member 21 engaged with the X-guide rail 19 in a non-contact manner.

[0091] The movable stage 24 is supported from below by the movable members 23a and 23b through two (four in total) single-axis guide rail devices on the +X side and the -X side, so that it can move on the movable members 23a and 23b in the X-axis direction. Therefore, when the slide 10 is driven in the X-axis direction by the aforementioned first drive device 20A, the reaction force of the driving force acts on the movable stage 24 provided with the fixing members 26a and 26b, and the movable stage 24 moves in the opposite direction to the slide 10 according to the law of conservation of momentum. That is, by the movement of the movable stage 24, the generation of vibration caused by the reaction force of the driving force in the X-axis direction of the slide 10 is prevented (or effectively suppressed). That is, the movable stage 24 functions as a counterweight when the slide 10 moves in the X-axis direction. However, it is not necessarily necessary to make the movable stage 24 function as a counterweight. Furthermore, the slide 10 only moves slightly along the Y-axis direction relative to the movable carrier 24, so there is no need to specially set a balancing mass. However, a balancing mass may be set to prevent (or effectively suppress) the generation of vibrations caused by the driving force that drives the slide 10 along the Y-axis direction relative to the movable carrier 24.

[0092] The Y-axis linear motor 29A generates a driving force (electromagnetic force) for driving the movable part 23a along the Y-axis direction through the electromagnetic interaction between the movable part 23a and the fixed part 25a, and the Y-axis linear motor 29B generates a driving force (electromagnetic force) for driving the movable part 23b along the Y-axis direction through the electromagnetic interaction between the movable part 23b and the fixed part 25b.

[0093] The driving force in the Y-axis direction generated by the Y-axis linear motors 29A and 29B acts on the movable stage 24 through the two single-axis guide rail devices on the +X side and the -X side. In this way, the slider 10 and the movable stage 24 are driven in the Y-axis direction as a whole. That is, in this embodiment, the second driving device 20B (refer to FIG. 2 ) for driving the slider 10 in the Y-axis direction is composed of the movable stage 24, the four single-axis guide rail devices, and the pair of Y-axis linear motors 29A and 29B. Fig. 9 ).

[0094] In the present embodiment, the pair of Y-axis linear motors 29A and 29B are physically separated from the surface plate 12, and are also separated in vibration by the three vibration isolating devices 14. Furthermore, the linear guides 27a and 27b of the stators 25a and 25b provided with the pair of Y-axis linear motors 29A and 29B can be configured to be movable in the Y-axis direction relative to the base frame 16, so as to function as a counterweight when the slider 10 is driven in the Y-axis direction.

[0095] The measuring unit 40 is as follows Figure 4 As shown, it comprises: a unit body 42, which has a cut-out cavity 42a with a bottom opening formed on the surface of the -Y side; the aforementioned mark detection system MDS, which is connected to the unit body 42 with the base end portion inserted into the cavity 42a; and a connecting mechanism 43, which connects the barrel portion 41 at the front end of the mark detection system MDS to the unit body 42.

[0096] The connecting mechanism 43 includes: a support plate 44, which supports the lens barrel portion 41 on the back side (+Y side) through a mounting component not shown; and a pair of support arms 45a, 45b, which support the support plate 44 at one end thereof and are fixed to the bottom surface of the unit body 42 at the other end.

[0097] In the present embodiment, a sensitive agent (resist) is coated on the upper surface of the wafer held on the slide 10, and correspondingly, a detection light beam with a wavelength that does not make the resist sensitive to light is used as the mark detection system MDS. As the mark detection system MDS, for example, an FIA (Field Image Alignment) system using an image processing method is used, that is, a broadband detection light beam that does not make the resist coated on the wafer sensitive to light is irradiated onto the object mark, and an image of the object mark formed on the light receiving surface by the reflected light from the object mark and an image of an indicator (an indicator pattern on an indicator plate provided inside) not shown in the figure are captured using an imaging element (CCD, etc.), and the imaging signals are output. The imaging signals from the mark detection system MDS are processed by a signal processing device 49 ( Figure 4 Not shown in the figure, refer to Fig. 9 ) and supplied to the control device 60 i (Refer to Fig. 9). The mark detection system MDS has an alignment autofocus function for adjusting the focal position of the optical system.

[0098] Between the lens barrel 41 and the support plate 44, as shown in FIG. Figure 4 As shown, a head mounting member 51 having a substantially isosceles triangle shape is provided. Figure 4 The lens barrel 41 is mounted (fixed) to the support plate 44 by a mounting member (not shown) inserted into the opening. The back of the head mounting member 51 is also fixed to the support plate 44. In this way, the lens barrel 41 (mark detection system MDS), the head mounting member 51 and the support plate 44 are integrated with the unit body 42 via a pair of support arms 45a and 45b.

[0099] The signal processing device 49 is disposed inside the unit body 42. The signal processing device 49 processes the image signal outputted from the mark detection system MDS as a detection signal, calculates the position information of the object mark relative to the detection center, and outputs it to the control device 60. i The unit body 42 is supported at three points from below by a plurality of, for example, three, vibration isolation devices 48 on a support frame 46 that is provided on the base frame 16 and is door-shaped when viewed from the -Y side. Each vibration isolation device 48 is an active vibration isolation system (so-called AVIS (Active Vibration Isolation System)) and is equipped with an accelerometer, a displacement sensor (such as an electrostatic capacitance sensor, etc.), an actuator (such as a voice coil motor, etc.), and a mechanical damper such as an air damper or a hydraulic damper. The vibration isolation device 48 can attenuate relatively high-frequency vibrations by means of a mechanical damper, and can perform vibration isolation (vibration reduction) by means of an actuator. Therefore, each vibration isolation device 48 can prevent relatively high-frequency vibrations from being transmitted between the support frame 46 and the unit body 42.

[0100] Furthermore, as the mark detection system MDS, it is not limited to the FIA ​​system. For example, a diffraction light interference type alignment detection system can be used to replace the FIA ​​system. The diffraction light interference type alignment detection system irradiates the coherent detection light to the object mark, so that two diffraction lights (for example, diffraction lights of the same order, or diffraction lights diffracted in the same direction) generated from the object mark interfere and detect, and output a detection signal. Alternatively, the diffraction light interference type alignment system can also be used together with the FIA ​​system to simultaneously detect two object marks. Furthermore, as the mark detection system MDS, a beam scanning type alignment system can also be used. The beam scanning type alignment system is to scan the object mark along a predetermined direction while the slider 10 is moved in a predetermined direction. In addition, in this embodiment, the mark detection system MDS has an alignment autofocus function, but it can also replace or in addition to it, the measurement unit 40 has a focus position detection system, for example, a multi-point focus position detection system of an oblique incidence method with the same structure as that disclosed in the specification of U.S. Patent No. 5,448,332.

[0101] The first position measurement system 30 is shown in FIG. 5(B) and Figure 6 As shown, there is a head portion 32, which is arranged in a recess formed on the upper surface of the plate 12 and fixed to the plate 12. The upper surface of the head portion 32 faces the lower surface (the surface on which the grating RG1 is formed) of the slider 10. Between the upper surface of the head portion 32 and the lower surface of the slider 10, a predetermined clearance (gap, space) is formed, for example, a clearance of about several mm.

[0102] The first position measuring system 30 is as follows Fig. 9 As shown, the encoder system 33 and the laser interferometer system 35 are provided. The encoder system 33 can irradiate a plurality of light beams from the head 32 to the measuring portion (the formation surface of the grating RG1) on the lower surface of the slider 10, and receive a plurality of return light beams (for example, a plurality of diffracted light beams from the grating RG1) from the measuring portion on the lower surface of the slider 10, so as to obtain the position information of the slider 10. The encoder system 33 includes an X linear encoder 33x for measuring the position of the slider 10 in the X-axis direction, and a pair of Y linear encoders 33ya and 33yb for measuring the position of the slider 10 in the Y-axis direction. In the encoder system 33, for example, a diffraction interferometer type head having the same structure as the encoder head disclosed in the specification of U.S. Patent No. 7,238,931 and the specification of U.S. Patent Application Publication No. 2007 / 288,121 (hereinafter referred to as the head as appropriate) is used. Furthermore, the reader includes a light source and a light receiving system (including a light detector), and an optical system. However, in this embodiment, as long as at least the optical system is arranged inside the frame of the reader head 32 opposite to the grating RG1, at least one of the light source and the light receiving system may also be arranged outside the frame of the reader head 32.

[0103] FIG. 7(A) shows the head 32 in a stereoscopic view, and FIG. 7(B) shows a top view of the upper surface of the head 32 viewed from the +Z direction. The encoder system 33 uses one X head 37x to measure the position of the slider 10 in the X-axis direction, and uses a pair of Y heads 37ya and 37yb to measure the position in the Y-axis direction (see FIG. 7(B)). That is, the X head 37x that measures the position of the slider 10 in the X-axis direction using the X diffraction grid of the grating RG1 constitutes the X linear encoder 33x, and the pair of Y heads 37ya and 37yb that measure the position of the slider 10 in the Y-axis direction using the Y diffraction grid of the grating RG1 constitutes a pair of Y linear encoders 33ya and 33yb.

[0104] As shown in FIG. 7(A) and FIG. 7(B), the X head 37x irradiates the measuring beams LBx1 and LBx2 (shown by solid lines in FIG. 7(A)) to the same irradiation point on the grating RG1 from two points (see the white circles in FIG. 7(B)) on the straight line LX passing through the center of the head 32 and parallel to the X axis and the straight line CL passing through the center of the head 32 and parallel to the Y axis, respectively. For the irradiation points of the measuring beams LBx1 and LBx2, i.e., the detection points of the X head 37x (see the symbol DP in FIG. 7(B)), the positions in the X-axis direction and the Y-axis direction coincide with the detection center of the mark detection system MDS.

[0105] Here, the measuring beams LBx1 and LBx2 are obtained by polarizing and separating the beams from the light source by a polarizing beam splitter not shown. When the measuring beams LBx1 and LBx2 are irradiated onto the grating RG1, the measuring beams LBx1 and LBx2 are diffracted a predetermined number of times by the X-diffraction grating, for example, the 1st diffracted beam (1st diffracted beam) passes through a lens not shown and a quarter-wave plate respectively and is reflected by a reflector, and passes through the quarter-wave plate twice, thereby rotating the polarization direction by 90 degrees, and then entering the polarizing beam splitter again through the original optical path to be synthesized into a coaxial beam. Then, the interference light of the 1st diffracted beams of the measuring beams LBx1 and LBx2 is received by a detector not shown, thereby measuring the position of the slider 10 in the X-axis direction.

[0106] As shown in FIG7(B), a pair of Y heads 37ya and 37yb are respectively arranged on the +X side and -X side of the straight line CL. As shown in FIG7(A) and FIG7(B), the Y head 37ya is irradiated from two points on the straight line LYa at equal distances from the straight line LX (see the white circle in FIG7(B)) to the common irradiation point on the grating RG1 with the measuring beams LBya1 and LBya2 respectively indicated by the dotted lines in FIG7(A). The irradiation points of the measuring beams LBya1 and LBya2, i.e., the detection points of the Y head 37ya are indicated by the symbol DPya in FIG7(B).

[0107] The Y head 37yb irradiates the measuring beams LByb1 and LByb2 to a common irradiation point DPyb on the grating RG1 from two points symmetrical to the emission points of the measuring beams LBya1 and LBya2 of the Y head 37ya with respect to the straight line CL (see the white circle in FIG. 7(B)). As shown in FIG. 7(B), the respective detection points DPya and DPyb of the Y heads 37ya and 37yb are arranged on a straight line LX parallel to the X-axis.

[0108] The measuring beams LBya1 and LBya2 are also polarized and separated from the same beam by a polarizing beam splitter. The measuring beams LBya1 and LBya2 become predetermined diffracted beams (second diffracted beams) through the Y diffraction lattice. The interference lights between the diffracted beams LBya1 and LBya2 are photoelectrically detected by a detector (not shown) in the same manner as described above, thereby measuring the position of the slider 10 in the Y-axis direction. For the measuring beams LByb1 and LByb2, the interference lights between the first diffracted beams (second diffracted beams) are photoelectrically detected by a detector (not shown) in the same manner as the measuring beams LBya1 and LBya2, thereby measuring the position of the slider 10 in the Y-axis direction.

[0109] Here, the control device 60 i The position of the slider 10 in the Y-axis direction is determined based on the average of the measurement values ​​of the two Y reading heads 37ya and 37yb. Therefore, in this embodiment, the position of the slider 10 in the Y-axis direction is measured by taking the midpoint DP of the detection points DPya and DPyb as the actual measurement point. The midpoint DP coincides with the irradiation point of the measurement beams LBx1 and LBX2 on the grating RG1.

[0110] That is, in this embodiment, the position information of the slider 10 in the X-axis direction and the Y-axis direction is measured with a common detection point, and the control device 60 i The actuators of the three vibration isolation devices 14 are controlled in real time so that the position of the detection point in the XY plane is consistent with the detection center of the mark detection system MDS, for example, at the nm level. The control of the actuators of the three vibration isolation devices 14 is performed based on the relative position information of the mark detection system MDS (measuring unit 40) and the fixed plate 12 measured by the second position measurement system 50. Therefore, in this embodiment, the control device 60 i By using the encoder system 33, when measuring the alignment mark on the wafer W placed on the slider 10, the position information of the slider 10 in the XY plane can be measured at the nearest position below the detection center of the mark detection system MDS (the back side of the slider 10). i The rotation amount of the slider 10 in the θz direction is measured based on the difference in the measurement values ​​of the pair of Y heads 37 ya and 37 yb.

[0111] The laser interferometer system 35 can make the measuring beam incident on the measuring part (the surface formed with the grating RG1) on the lower surface of the slider 10, and receive its return beam (for example, the reflected light from the surface formed with the grating RG1) to obtain the position information of the slider 10. As shown in FIG. 7(A), the laser interferometer system 35 makes four measuring beams LBz1, LBz2, LBz3, and LBz4 incident on the lower surface (the surface formed with the grating RG1) of the slider 10. The laser interferometer system 35 has laser interferometers 35a to 35d (see FIG. 7(A) ) that respectively irradiate the four measuring beams LBz1, LBz2, LBz3, and LBz4. Fig. 9 ) In this embodiment, four Z heads are constituted by laser interferometers 35a to 35d.

[0112] In the laser interferometer system 35, as shown in FIG. 7(A) and FIG. 7(B), four length measuring beams LBz1, LBz2, LBz3, and LBz4 are emitted parallel to the Z axis from four points corresponding to the vertices of a square, and the square is centered at the detection point DP and has two sides parallel to the X axis and two sides parallel to the Y axis. At this time, the emission points (irradiation points) of the length measuring beams LBz1 and LBz4 are equidistant from the straight line LX on the straight line LYa, and the emission points (irradiation points) of the remaining length measuring beams LBz2 and LBz3 are equidistant from the straight line LX on the straight line LYb. In this embodiment, the surface on which the grating RG1 is formed also serves as a reflection surface for each length measuring beam from the laser interferometer system 35. Control device 60 i The laser interferometer system 35 is used to measure the information of the position of the slider 10 in the Z-axis direction and the amount of rotation in the θx direction and the θy direction. Furthermore, it can be clearly understood from the above description that the slider 10 is not actively driven by the aforementioned drive system 20 relative to the fixed plate 12 in each direction of the Z-axis, θx and θy, but is suspended and supported on the fixed plate 12 by four air bearings 18 arranged at the four corners of the bottom surface. Therefore, in fact, the position of the slider 10 in each direction of the Z-axis, θx and θy changes on the fixed plate 12. That is, the slider 10 is actually movable relative to the fixed plate 12 in each direction of the Z-axis, θx and θy. In particular, the displacement of the slider 10 in each direction of θx and θy will generate a measurement error (Abbe error) of the encoder system 33. In view of this point, the position information of the slider 10 in each direction of the Z-axis, θx and θy is measured by the first position measurement system 30 (laser interferometer system 35).

[0113] Furthermore, in order to measure the information of the position of the slider 10 in the Z-axis direction and the amount of rotation in the θx direction and the θy direction, it is sufficient to allow the light beam to be incident on three different points on the surface on which the grating RG1 is formed, so three Z heads, such as laser interferometers, are sufficient. Furthermore, a protective glass for protecting the grating RG1 may be provided on the lower surface of the slider 10, and a wavelength selective filter may be provided, which allows each measuring light beam from the encoder system 33 to pass through the surface of the protective glass and blocks each length measuring light beam from the laser interferometer system 35 from passing through.

[0114] According to the above description, the control device 60 i By using the encoder system 33 and the laser interferometer system 35 of the first position measurement system 30, the position of the slider 10 in the 6-DOF direction can be measured. At this time, in the encoder system 33, the optical path length of the measuring beam in the air is extremely short, and the optical path lengths of the two measuring beams LBx1 and LBx2 irradiated from the X head 73x to the grating RG1, the optical path lengths of the two measuring beams LBya1 and LBya2 irradiated from the Y head 37ya to the grating RG1, and the optical path lengths of the measuring beams LByb1 and LByb2 irradiated from the Y head 37yb to the grating RG1 are substantially equal to each other, so the influence of air disturbance can be substantially ignored. Therefore, by using the encoder system 33, the position information of the slider 10 in the XY plane (including the θz direction) can be measured with high precision. Furthermore, the detection points on the grating RG1 in the X-axis direction and the Y-axis direction by the encoder system 33, and the detection points on the lower surface of the slide 10 in the Z-axis direction by the laser interferometer system 35, are respectively aligned with the detection center of the mark detection system MDS in the XY plane, so that the so-called Abbe error caused by the deviation between the detection point and the detection center of the mark detection system MDS in the XY plane can be suppressed to a substantially negligible level. Therefore, the control device 60 i By using the first position measurement system 30 , the position of the slider 10 in the X-axis direction, the Y-axis direction, and the Z-axis direction can be measured with high accuracy without causing Abbe errors due to deviations between the detection point and the detection center of the mark detection system MDS in the XY plane.

[0115] However, regarding the Z-axis direction parallel to the optical axis AX1 of the mark detection system MDS, the position information of the slider 10 in the XY plane is not measured by the encoder system 33 at the position on the surface of the wafer W, that is, the Z position of the configuration surface of the grating RG1 and the surface of the wafer W do not coincide. Therefore, in the case where the grating RG1 (that is, the slider 10) is tilted relative to the XY plane, if the slider 10 is positioned based on the measurement values ​​of the encoders of the encoder system 33, as a result, a positioning error (a kind of Abbe error) corresponding to the tilt of the grating RG1 relative to the XY plane will be generated due to the difference ΔZ between the Z positions of the configuration surface of the grating RG1 and the surface of the wafer W (that is, the position deviation of the detection point of the encoder system 33 and the detection center (detection point) of the mark detection system MDS in the Z-axis direction). However, the positioning error (position control error) can be obtained by simple calculation using the difference ΔZ and the pitch amount θx and the roll amount θy, and the difference ΔZ can be used as a compensation value. The slider 10 is positioned based on the corrected position information obtained by correcting the measured value of the encoder system 33 (of each encoder) by the compensation amount, thereby no longer being affected by the above-mentioned Abbe error. Alternatively, instead of correcting the measured value of the encoder system 33 (of each encoder), one or more information for moving the slider, such as the target position where the slider 10 should be positioned, can be corrected based on the above-mentioned compensation value.

[0116] Furthermore, when the grating RG1 (i.e., the slider 10) is tilted relative to the XY plane, the head section 32 may be moved to avoid positioning errors caused by the tilt. That is, when the first position measurement system 30 (e.g., the interferometer system 35) measures that the grating RG1 (i.e., the slider 10) is tilted relative to the XY plane, the platen 12 holding the head section 32 may be moved based on the position information obtained using the first position measurement system 30. As described above, the platen 12 may be moved using the vibration isolation device 14.

[0117] Furthermore, when the grating RG1 (ie, the slider 10 ) is tilted relative to the XY plane, the position information of the mark acquired using the mark detection system MDS can be corrected based on the positioning error caused by the tilt.

[0118] The second position measuring system 50 is as follows Figure 4As shown in FIG. 5(A) and FIG. 5(B), it has: a pair of read heads 52A, 52B, which are respectively arranged on the lower surface of one end and the other end in the length direction of the aforementioned read head mounting member 51; and scale members 54A, 54B, which are arranged opposite to the read heads 52A, 52B. The upper surface of the scale members 54A, 54B is set to the same height as the surface of the wafer W held in the wafer holder WH. Reflective two-dimensional gratings RG2a, RG2b are formed on the upper surfaces of the scale members 54A, 54B respectively. The two-dimensional gratings (hereinafter referred to as gratings) RG2a, RG2b both include: a reflective diffraction grating (X diffraction grating) with the X-axis direction set as the periodic direction; and a reflective diffraction grating (Y diffraction grating) with the Y-axis direction set as the periodic direction. The spacing of the grating lines of the X diffraction grating and the Y diffraction grating is set to 1μm, for example.

[0119] The scale members 54A and 54B are made of a material with a low thermal expansion coefficient, such as the aforementioned zero expansion material, and are fixed to the fixed plate 12 via support members 56, respectively, as shown in Fig. 5(A) and Fig. 5(B). In the present embodiment, the dimensions of the scale members 54A and 54B and the support member 56 are defined so that the gratings RG2a and RG2b face the read heads 52A and 52B with a gap of about several mm therebetween.

[0120] like Figure 8 As shown, one of the head parts 52A fixed to the lower surface of the end portion on the +X side of the head mounting member 51 includes an XZ head 58X1 with the X-axis and Z-axis directions as the measurement directions and a YZ head 58Y1 with the Y-axis and Z-axis directions as the measurement directions, which are housed in the same frame. The XZ head 58X1 (more precisely, the irradiation point of the measurement beam emitted by the XZ head 58X1 on the grating RG2a) and the YZ head 58Y1 (more precisely, the irradiation point of the measurement beam emitted by the YZ head 58Y1 on the two-dimensional grating RG2a) are arranged on the same straight line parallel to the Y axis.

[0121] The other head 52B is arranged symmetrically with the head 52A on a straight line (hereinafter referred to as a reference axis) LV passing through the optical axis AX1 of the mark detection system MDS and parallel to the Y axis, but has the same configuration as the head 52A. That is, the head 52B has an XZ head 58X2 and a YZ head 58Y2 arranged symmetrically with the XZ head 58X1 and the YZ head 58Y1 on the reference axis LV, and the irradiation points of the measurement light beams irradiated from the XZ head 58X2 and the YZ head 58Y2 to the grating RG2b are set on the same straight line parallel to the Y axis.

[0122] As each of the XZ heads 58X1 and 58X2 and the YZ heads 58Y1 and 58Y2, for example, an encoder head having the same structure as the displacement measuring sensor head disclosed in the specification of US Pat. No. 7,561,280 can be used.

[0123] The read heads 52A and 52B respectively use scale members 54A and 54B to form an XZ linear encoder for measuring the position of the grating RG2a and RG2b in the X-axis direction (X position) and the position in the Z-axis direction (Z position), and a YZ linear encoder for measuring the position in the Y-axis direction (Y position) and the Z position. Here, the gratings RG2a and RG2b are formed on the upper surfaces of the scale members 54A and 54B respectively fixed to the surface plate 12 by the support member 56, and the read heads 52A and 52B are provided in the read head mounting member 51 integrated with the mark detection system MDS. As a result, the read heads 52A and 52B measure the position of the surface plate 12 relative to the mark detection system MDS (the positional relationship between the mark detection system MDS and the surface plate 12). For convenience, the XZ linear encoder and the YZ linear encoder are represented by the same symbols as the XZ heads 58X1, 58X2 and the YZ heads 58Y1, 58Y2, and are represented by XZ linear encoders 58X1, 58X2 and YZ linear encoders 58Y1, 58Y2 (see Fig. 9 ).

[0124] In this embodiment, the four-axis encoder 581 is composed of the XZ linear encoder 58X1 and the YZ linear encoder 58Y1. The four-axis encoder 581 measures the position information of the surface plate 12 with respect to the mark detection system MDS in each direction of the X axis, Y axis, Z axis and θx (see Fig. 9 ). Similarly, the XZ linear encoder 58X2 and the YZ linear encoder 58Y2 form a 4-axis encoder 582, which measures the position information of the platen 12 relative to the mark detection system MDS in each direction of the X-axis, Y-axis, Z-axis and θx (see Fig. 9 ). At this time, based on the position information of the fixed plate 12 with respect to the mark detection system MDS with respect to the Z-axis direction measured by the four-axis encoders 581 and 582, respectively, the position information of the fixed plate 12 with respect to the mark detection system MDS with respect to the θy direction is calculated (measured), and based on the position information of the fixed plate 12 with respect to the mark detection system MDS with respect to the Y-axis direction measured by the four-axis encoders 581 and 582, respectively, the position information of the fixed plate 12 with respect to the mark detection system MDS with respect to the θz direction is calculated (measured).

[0125] Therefore, the 4-axis encoder 581 and the 4-axis encoder 582 constitute the second position measurement system 50, and the second position measurement system 50 measures the position information of the fixed plate 12 in the 6-degree-of-freedom direction relative to the mark detection system MDS, that is, the relative position information of the mark detection system MDS and the fixed plate 12 in the 6-degree-of-freedom direction. The relative position information of the mark detection system MDS and the fixed plate 12 in the 6-degree-of-freedom direction measured by the second position measurement system 50 is always supplied to the control device 60. i , control device 60 i Based on the relative position information, the actuators of the three vibration isolation devices 14 are controlled in real time so that the detection point of the first position measurement system 30 is in a desired positional relationship with respect to the detection center of the mark detection system MDS. Specifically, the position of the detection point of the first position measurement system 30 in the XY plane is consistent with the detection center of the mark detection system MDS, for example, at the nm level, and the surface of the wafer W on the slide 10 is consistent with the detection position of the mark detection system MDS. At this time, the straight line CL is consistent with, for example, the reference axis LV. Furthermore, as long as the detection point of the first position measurement system 30 can be controlled to be in a desired positional relationship with respect to the detection center of the mark detection system MDS, the second position measurement system 50 can be used even if it is unable to measure the relative position information in all directions of the six degrees of freedom.

[0126] According to the description of the first position measurement system 30 and the description of the second position measurement system 50, in the measurement device 100 i In the embodiment, the first position measuring system 30 and the second position measuring system 50 constitute a position measuring system, which measures the position information of the slider 10 in the six-degree-of-freedom directions relative to the mark detection system MDS.

[0127] Fig. 9 A block diagram showing a main structure of the measuring device 100 of the present embodiment is shown. i Control device 60 of the control system i The input / output relationship of the control device 60 i Including workstation (or microcomputer), etc., unified control measurement device 100 i The components of Fig. 9 As shown, the measuring device 100 i Equipped with wafer transport system 70 i , the wafer transport system 70 i part of Figure 4 The components shown are arranged together in the chamber 101 i Wafer handling system 70 i As described above, it is composed of, for example, a horizontal multi-joint robot.

[0128] Next, in the measuring device 100 of the present embodiment configured as described above, i In the process of processing a batch of wafers, a series of actions are performed based on the control device 60. i The processing algorithm corresponds to Fig.10 The flowchart is described below.

[0129] As a premise, the measuring device 100 i The measurement object, i.e., wafer W, is a 300 mm wafer. On wafer W, a plurality of, for example, I (as an example, I=98) partitioned areas called irradiation areas (hereinafter referred to as irradiation areas) are formed in a matrix configuration by the previous exposure of the front layer. On the boundary surrounding each irradiation area or the boundary inside each irradiation area (when multiple wafers are taken in one irradiation area), a variety of marks such as search alignment marks (search marks) for search alignment, wafer alignment marks (wafer marks) for fine alignment, etc. are provided. The various marks are formed together with the irradiation area. In this embodiment, a 2D mark is used as a search mark and a wafer mark.

[0130] Furthermore, the measuring device 100 i A plurality of measurement modes with different mark detection conditions of the mark detection system MDS can be set. As a plurality of measurement modes, for example, an A mode and a B mode can be set, wherein the A mode detects one wafer mark for each irradiation area for all wafers, and the B mode detects multiple wafer marks for all irradiation areas for the first predetermined number of wafers in a batch, and based on the detection results of the wafer marks, for the remaining wafers in the batch, a wafer mark to be detected is determined for each irradiation area, and the determined wafer mark is detected.

[0131] Furthermore, the measuring device 100 i The operator inputs information required for alignment measurement of the wafer W in advance through an input device (not shown) and stores it in the control device 60. i Here, the information required for alignment measurement includes various information such as thickness information of wafer W, flatness information of wafer holder WH, design information of the irradiation area and alignment mark configuration on wafer W, etc. Furthermore, the setting information of the measurement mode is pre-inputted by the operator through an input device not shown, for example.

[0132] and Fig.10 The processing algorithm corresponding to the flowchart of FIG. 1 is started, for example, when an operator or the host computer 2000 indicates that a measurement is to be started. At this time, a plurality of wafers (for example, 25 wafers) included in a batch are stored in the measuring device 100. i Chamber 101 iThe wafer carrier is placed in a predetermined position within the wafer carrier. i In parallel with the measurement processing, the wafers of one batch are sequentially loaded into the measurement device 100. i For example, under the management of the measurement system control device 530 that controls the robot 516, the conveying member 524, and the conveying member 526, a batch of wafers in a predetermined FOUP 520 can be taken out in sequence by the robot 516 and conveyed to the measurement device 100 by the conveying member 524. i At this time, Fig.10 The processing algorithm corresponding to the flowchart of FIG. 1 is started by the measurement system control device 530 to the control device 60 i And when the robot 516 gives an instruction to start conveying.

[0133] Furthermore, when the exposure device 200 and the measurement system 500 are connected, the exposure control device 220 of the exposure device 200 may instruct the measurement system control device 530 to start measurement without going through the host computer 2000 .

[0134] Furthermore, the measuring device 100 i A barcode reader (not shown) is provided in the wafer transport system 70 i (Refer to Fig. 9 ) During the transport of the wafers, the identification information of each wafer, such as the wafer number, the batch number, etc., is appropriately read by the barcode reader. In the following, for the sake of simplicity, the description related to the reading of the identification information of each wafer using the barcode reader is omitted. i It is also not necessary to provide a barcode reader for each of them. For example, a barcode reader may be arranged in the conveying system 521.

[0135] First, in step S102 , the count value i of the counter representing the wafer number in the lot is initialized to 1 (i←1).

[0136] In the next step S104, the wafer W is loaded onto the slide 10. The loading of the wafer W is performed by the control device 60. i Under the management of the wafer transport system 70 i Specifically, the wafer transfer system 70 i , the wafer W is transported from the wafer carrier (or the conveying position) to the top of the slide 10 located at the loading position, and the vertical moving member is driven to rise by a predetermined amount by the driving device 13, thereby delivering the wafer W to the vertical moving member. Then, the wafer transport system 70 iAfter retreating from above the slider 10, the driving device 13 drives the vertical moving member downward, thereby placing the wafer W on the wafer holder WH on the slider 10. Then, the vacuum pump 11 is turned on, and the wafer W loaded on the slider 10 is vacuum-absorbed by the wafer holder WH. i The measurement process is performed in parallel, and a plurality of wafers included in one batch are sequentially carried into the measurement device 100. i In the case of the above wafer loading, before the wafer loading, the robot 516 first takes out the plurality of wafers in the predetermined FOUP 520 one by one, and transfers them from the robot 516 to the conveying member 524, and then conveys them to the measuring device 100 by the conveying member 524. i The wafer is then delivered to the wafer handling system 70. i .

[0137] In the next step S106, the position of the wafer W in the Z-axis direction (Z position) is adjusted. Before the Z position is adjusted, the control device 60 i Based on the relative position information of the mark detection system MDS and the platen 12 in the Z-axis direction, the θy direction, and the θx direction measured by the second position measurement system 50, the internal pressure of the air shock absorbers of the three vibration isolation devices 14 (the driving force in the Z-axis direction generated by the vibration isolation device 14) is controlled to set the platen 12 so that its upper surface is parallel to the XY plane and the Z position is at a predetermined reference position. The wafer W can be considered to have the same thickness. Therefore, in step S106, the control device 60 i Based on the thickness information of the wafer W in the memory, the driving force in the Z-axis direction generated by the three vibration isolation devices 14, such as the internal pressure of the air shock absorber (the amount of compressed air), is adjusted to drive the platen 12 along the Z-axis direction to adjust the Z position of the surface of the wafer W so that the surface of the wafer W is set within the range in which the focus position of the optical system can be adjusted by the autofocus function of the mark detection system MDS. Furthermore, when the measurement unit 40 is equipped with a focus position detection system, the control device 60 iThe Z position of the wafer surface can also be adjusted based on the detection result (output) of the focus position detection system. For example, the mark detection system MDS can also be equipped with a focus position detection system, which detects the position of the surface of the wafer W in the Z-axis direction through an optical element (object optical element) at the front end. In addition, the adjustment of the Z position of the surface of the wafer W based on the detection result of the focus position detection system can be performed by the following operation, that is, using the vibration isolation device 14 to move the fixed plate 12 so that the movable slide 10 moves together with the fixed plate 12. Furthermore, a drive system 20 that can drive the slide 10 not only in the direction within the XY plane but also in the Z-axis direction, the θx direction and the θy direction can be used to move the slide 10. Furthermore, the Z position adjustment of the wafer surface can also include the tilt adjustment of the wafer surface. By using the drive system 20 to adjust the tilt of the wafer surface, when an error (a type of Abbe error) may occur due to the difference ΔZ in the Z position between the arrangement surface of the grating RG1 and the surface of the wafer W, at least one of the above-mentioned countermeasures may be performed.

[0138] In the next step S108, search alignment of the wafer W is performed. Specifically, the mark detection system MDS is used to detect at least two search marks located at the periphery of the wafer W, which are approximately symmetrical with respect to the center of the wafer W. The control device 60 i The control drive system 20 drives the slide 10, positions each search mark within the detection area (detection field of view) of the mark detection system MDS, and obtains the measurement information of the first position measurement system 30 and the measurement information of the second position measurement system 50. Based on the detection signal when the search mark formed on the wafer W is detected using the mark detection system MDS and the measurement information of the first position measurement system 30 (and the measurement information of the second position measurement system 50), the position information of each search mark is calculated.

[0139] More specifically, the control device 60 i Based on the detection result of the mark detection system MDS output from the signal processing device 49 (the relative position relationship between the detection center (index center) of the mark detection system MDS obtained from the detection signal and each search mark), and the measurement value of the first position measurement system 30 (and the measurement value of the second position measurement system 50) when each search mark is detected, the position coordinates of the two search marks on the reference coordinate system are obtained. That is, the control device 60 iThe position coordinates of the two search marks on the reference coordinate system are obtained based on the relative position relationship between the detection center (index center) of the mark detection system MDS and each search mark obtained from the detection signal of the mark detection system MDS, the measurement value of the first position measurement system 30 when each search mark is detected, and the measurement value of the second position measurement system 50. Here, the reference coordinate system is an orthogonal coordinate system defined by the length measurement axis of the first position measurement system 30.

[0140] Then, the residual rotation error of the wafer W is calculated from the position coordinates of the two search marks, and the slide 10 is slightly rotated so that the rotation error is substantially zero. In this way, the search alignment of the wafer W is completed. Furthermore, the wafer W is actually loaded on the slide 10 in a pre-aligned state, so the center position deviation of the wafer W is small to a negligible degree, and the residual rotation error is very small.

[0141] In the next step S110 , it is determined whether the set measurement mode is mode A. If the determination in step S110 is affirmative, that is, if the mode is set to mode A, the process proceeds to step S112 .

[0142] In step S112, alignment measurement is performed for all wafers (one-point measurement of the entire irradiation area, in other words, full irradiation area EGA measurement), that is, one wafer mark is measured for each of the 98 irradiation areas. i In the same manner as the measurement of the position coordinates of each search mark during the search alignment, the position coordinates of the wafer mark on the wafer W on the reference coordinate system, that is, the position coordinates of the irradiation area, are obtained. However, unlike the search alignment, the measurement information of the second position measurement system 50 must be used when calculating the position coordinates of the irradiation area. The reason for this is that, as described above, the control device 60 i Based on the measurement information of the second position measurement system 50, the actuators of the three vibration isolation devices 14 are controlled in real time so that the position of the detection point of the first position measurement system 30 in the XY plane is consistent with the detection center of the mark detection system MDS, for example, at the nm level, and the surface of the wafer W on the slide 10 is consistent with the detection position of the mark detection system MDS. However, when detecting the wafer mark, compensation is not performed to make the position of the detection point of the first position measurement system 30 in the XY plane consistent with the detection center of the mark detection system MDS, for example, at the nm level. Therefore, the positional deviation of the two must be considered as a compensation value to calculate the position coordinates of the irradiation area. For example, by using the above-mentioned compensation value to correct the detection result of the mark detection system MDS or the measurement value of the first position measurement system 30, the calculated position coordinates of the wafer mark on the wafer W on the reference coordinate system can be corrected.

[0143] Here, when measuring at one point in the entire irradiation area, the control device 60 i Based on the measurement information of the first position measurement system 30 and the measurement information of the second position measurement system 50, the slider 10 (wafer W) is moved in at least one of the X-axis direction and the Y-axis direction by the driving system 20, and the wafer mark is positioned within the detection area of ​​the mark detection system MDS. That is, the slider 10 is moved relative to the mark detection system MDS in the XY plane in a step-and-repeat manner to perform one-point measurement of the entire irradiation area.

[0144] Furthermore, when the measurement unit 40 is provided with a focus position detection system, the control device 60 may also be configured to detect the focus position of the measuring unit 40 in the same manner as described in step S106. i The Z position of the wafer surface is adjusted based on the detection result (output) of the focus position detection system.

[0145] During the alignment measurement for all wafers in step S112 (one-point measurement of the entire irradiation area), if the slider 10 moves in the XY plane, an unbalanced load will act on the platen 12 with the movement. However, in this embodiment, the control device 60 i Based on the X and Y coordinate positions of the slide included in the measurement information of the first position measurement system 30, the three vibration isolation devices 14 are individually feedforward controlled, thereby individually controlling the driving force in the Z-axis direction generated by each vibration isolation device 14 so that the influence of the unbalanced load is offset. i It is also possible to predict the unbalanced load acting on the platen 12 based on the known moving path information of the slider 10 instead of using the measurement information of the first position measurement system 30, and perform feedforward control on the three vibration isolation devices 14 individually so that the influence of the unbalanced loads cancel each other out. In addition, in the present embodiment, the concave-convex information of the wafer holding surface (the surface defined by the upper end surfaces of the plurality of pins of the pin clamp) of the wafer holder WH (hereinafter referred to as the holder flatness information) is obtained in advance through experiments, etc., so when the slider 10 is moved during alignment measurement (for example, measurement of one point in the entire irradiation area), the control device 60 i Based on the flatness information of the holder, the three vibration isolating devices 14 are feedforward controlled, thereby finely adjusting the Z position of the surface plate 12 so that the area including the wafer mark to be measured on the surface of the wafer W is quickly located within the focal depth range of the optical system of the mark detection system MDS. Furthermore, either or both of the feedforward control for canceling out the influence of the unbalanced load acting on the surface plate 12 and the feedforward control based on the flatness information of the holder may not be performed.

[0146] Furthermore, when the magnification of the mark detection system MDS is adjustable, it can be set to a low magnification during the search alignment and set to a high magnification during the alignment measurement. In addition, when the center position deviation and residual rotation error of the wafer W loaded on the slide 10 are small enough to be ignored, step S108 can be omitted.

[0147] In the one-point measurement of the entire irradiation area in step S112, the measured values ​​of the position coordinates of the sampled irradiation area (sampled irradiation area) in the reference coordinate system used in the EGA calculation described later are detected. The so-called sampled irradiation area refers to a specific plurality of (at least 3) irradiation areas predetermined as users in the EGA calculation described later among all irradiation areas on the wafer W. Furthermore, in the one-point measurement of the entire irradiation area, all irradiation areas on the wafer W become sampled irradiation areas. After step S112, proceed to step S124.

[0148] On the other hand, when the judgment in step S110 is negative, that is, when the B mode is set, the process moves to step S114 to determine whether the count value i is less than a predetermined number K (K is a natural number that satisfies 1<K<I and is a predetermined number, such as 4). Furthermore, the count value i is incremented in step S128 described later. And, when the judgment in step S114 is positive, the process moves to step S120 to perform multi-point measurement of the entire irradiation area. Here, the so-called multi-point measurement of the entire irradiation area refers to measuring multiple wafer marks for all irradiation areas on wafer W. The multiple wafer marks that are the measurement objects are predetermined. For example, multiple wafer marks that can be configured to obtain the shape of the irradiation area (shape error from the ideal grid) by statistical calculation can also be set as the measurement object. The measurement process is the same as the case of single-point measurement of the entire irradiation area in step S112, except that the number of marks that are the measurement objects is different, so detailed description is omitted. After step S120, the process proceeds to step S124.

[0149] On the other hand, if the determination in step S114 is negative, the process proceeds to step S116 to determine whether the count value i is less than K + 1. Here, if the determination in step S116 is positive, the count value i satisfies i≧K and i<K+1, and thus i=K.

[0150] When the judgment of step S116 is affirmative, the process proceeds to step S118, and based on the detection results of the wafer marks of K-1 wafers (for example, 3 wafers when K=4) W that have been measured so far, the wafer marks that should be set as the measurement objects are determined for each irradiation area. Specifically, it is determined whether the detection of one wafer mark is sufficient for each irradiation area, or whether multiple wafer marks should be detected. In the latter case, it is also determined which wafer mark is set as the detection object. For example, the difference (absolute value) between the actual measured position and the design position of each of the multiple wafer marks is calculated for each irradiation area, and whether the difference between the maximum value and the minimum value of the difference exceeds a certain threshold value is determined for each irradiation area. Whether multiple wafer marks should be detected, or the detection of one wafer mark is sufficient. In the former case, the wafer mark to be detected is determined, for example, by including the wafer mark with the largest difference (absolute value) between the actual measured position and the design position and the wafer mark with the smallest difference (absolute value). After step S118, the process proceeds to step S122.

[0151] On the other hand, when the judgment in step S116 is negative, the process proceeds to step S122. Here, the judgment in step S116 is negative when the count value i satisfies K+1≦i, and before that, the count value i=K, and the wafer mark to be measured is determined for each irradiation area in step S118.

[0152] In step S122, the wafer marks to be measured that are determined for each irradiation area in step S118 are measured. The measurement process is the same as the case of measuring one point in the entire irradiation area in step S112, except that the number of marks to be measured is different, so detailed description is omitted. After step S122, the process moves to step S124.

[0153] According to the description so far, in the case of mode B, multi-point measurement of the entire irradiation area is performed for the 1st to K-1th (for example, the 3rd) wafers in the batch, and for the Kth (for example, the 4th) to the Ith (for example, the 25th) wafers, the wafer marks determined by each irradiation area are measured based on the results of the multi-point measurement of the entire irradiation area of ​​the initial K-1 (for example, 3rd) wafers.

[0154] In step S124, the position information of the wafer mark measured in any one of step S112, step S120 and step S122 is used to perform EGA operation. The so-called EGA operation refers to the statistical operation as described below, that is, after the measurement of the wafer mark (EGA measurement), based on the data of the difference between the design value and the measured value of the position coordinates of the sampled irradiation area, the coefficients of the model formula expressing the relationship between the position coordinates of the irradiation area and the position coordinate correction amount of the irradiation area are calculated using statistical operations such as the least square method.

[0155] In the present embodiment, as an example, the following model formula is used for calculation of the correction amount of the position coordinates of the irradiation area from the design value.

[0156] [Formula 1]

[0157]

[0158] Here, dx and dy are the correction values ​​of the position coordinates of the irradiated area in the X-axis direction and the Y-axis direction from the design value, and X and Y are the designed position coordinates of the irradiated area on the wafer coordinate system with the center of the wafer W as the origin. That is, the above formula (1) is a polynomial related to the designed position coordinates X and Y of each irradiated area on the wafer coordinate system with the center of the wafer as the origin, and is a model formula for expressing the relationship between the position coordinates X and Y and the position coordinate correction value (alignment correction component) dx and dy of the irradiated area. Furthermore, in this embodiment, the rotation of the reference coordinate system and the wafer coordinate system is eliminated by the above-mentioned search alignment. Therefore, in the following, the reference coordinate system and the wafer coordinate system are not specifically distinguished, and all are regarded as the reference coordinate system for explanation.

[0159] Using model formula (1), the correction amount of the position coordinates of the irradiation area can be obtained based on the position coordinates X and Y of the irradiation area of ​​the wafer W. However, in order to calculate the correction amount, coefficients a0, a1, ..., b0, b1, ... must be obtained. After the EGA measurement, based on the data of the difference between the design value and the measured value of the position coordinates of the sampled irradiation area, statistical operations such as the least square method are used to obtain the coefficients a0, a1, ..., b0, b1, ... of the above formula (1).

[0160] After determining the coefficients a0, a1, ..., b0, b1, ... of the model formula (1), substitute the designed position coordinates X and Y of each irradiation area (dividing area) on the wafer coordinate system into the model formula (1) after the coefficients are determined, and calculate the correction amounts dx and dy of the position coordinates of each irradiation area. In this way, the actual arrangement of multiple irradiation areas (dividing areas) on the wafer W can be calculated (as deformation components, there are not only linear components but also nonlinear components).

[0161] However, in the case of an exposed wafer W, the waveform of the detection signal obtained as a measurement result may not be good for all wafer marks due to the influence of the process so far. If the position of the wafer mark for which the measurement result (the waveform of the detection signal) is bad is included in the above-mentioned EGA calculation, the position error of the wafer mark for which the measurement result (the waveform of the detection signal) is bad will have an adverse effect on the calculation results of the coefficients a0, a1, ..., b0, b1, ...

[0162] Therefore, in this embodiment, the signal processing device 49 sends only the measurement results of the wafer marks with good measurement results to the control device 60. i , control device 60 i The EGA operation is performed using the positions of all wafer marks for which the measurement results have been received. The degree of the polynomial in the above equation (1) is not particularly limited. The control device 60 i The result of the EGA operation is associated with the identification information of the wafer (e.g., wafer number, batch number), and stored in an internal or external storage device as an alignment history data file. Furthermore, the alignment history data file may also include information other than the EGA operation result (e.g., information of a mark used for the EGA operation).

[0163] When the EGA calculation of step S124 is completed, the process proceeds to step S126 to unload the wafer W from the slide 10. The unloading is performed by the control device 60 i The wafer transfer system 70 is managed by the reverse process of the loading process in step S104. i The measuring device 100 is used to move the slider 10 upward and downward. i In parallel with the measurement processing, the wafers of one batch are sequentially loaded into the measurement device 100. i Inside, and from the measuring device 100 i When the wafer W is unloaded in sequence, the wafer W after measurement is transferred by the wafer transfer system 70. i The wafer is handed over to the conveying member 526 , and after being conveyed to the aforementioned unloading side wafer transfer position by the conveying member 526 , it is returned to the predetermined FOPU 520 by the robot 516 .

[0164] In the next step S128, after the count value i of the counter is incremented by 1 (i←i+1), the process proceeds to step S130 to determine whether the count value i is greater than the total number of wafers in the batch I. Furthermore, if the determination in step S130 is negative, it is determined that the processing of all wafers in the batch has not yet been completed, and the process returns to step S104. Thereafter, the processes from step S104 to step S130 (including the determination) are repeated until the determination in step S130 is positive.

[0165] Furthermore, if the determination in step S130 is affirmative, it is determined that the processing has been completed for all wafers in the lot, and thus the series of processing in this routine is terminated.

[0166] As can be seen from the description so far, according to the measuring device 100 iDuring alignment measurement, for I (for example, 98) irradiation areas on wafer W, the position information (coordinate position information) of at least one wafer mark is measured respectively, and the coefficients a0, a1, ..., b0, b1, ... of the above formula (1) are obtained by using the position information and statistical operations such as the least square method. Therefore, for the deformation components of the wafer grid, not only the linear components but also the nonlinear components can be accurately obtained. Here, the so-called wafer grid refers to the grid formed by connecting the centers of the irradiation areas on wafer W arranged according to the irradiation area mapping (data related to the arrangement of the irradiation areas formed on wafer W). The correction amount (alignment correction component) dx and dy of the position coordinates of the irradiation areas for multiple irradiation areas is obtained to obtain the deformation components of the wafer grid. Furthermore, in this specification, the wafer grid is referred to as "grid" or "arrangement of irradiation areas (or irradiation areas)".

[0167] In the measurement system 500 of this embodiment, the measurement process along the aforementioned flowchart can be performed in parallel by using three measurement devices 1001 to 1003. That is, by using the measurement devices 1001 to 1003, the position of at least one wafer mark can be measured for each batch of wafers stored in the wafer carrier, a total of three batches of wafers, in substantially the same measurement processing time as one batch of wafers, and for the deformation components of the wafer grid, not only the linear components but also the nonlinear components can be accurately calculated. Furthermore, in parallel with the measurement process, each measurement device 1001 to 1003 can be used to perform the measurement process of at least one wafer mark on all irradiated areas of each wafer. i Wafers are loaded and removed from each measuring device 100 i When the wafers that have been measured are moved out, the three batches of wafers, which are respectively moved into the three FOUPs 520 in the three loading ports 514, can be processed in parallel. This allows the position of at least one wafer mark to be measured on all irradiated areas of the three batches of wafers in the same processing time as one batch of wafers. For the deformation components of the wafer grid, not only the linear components but also the nonlinear components can be accurately calculated.

[0168] The obtained information of the wafer grid of each wafer, for example, the obtained data of the deformation component of the wafer grid of each wafer (the data of the model formula (1) after the determination coefficients a0, a1, ..., b0, b1, ...) is obtained by the measuring device 100 as a part of the alignment history data file of each wafer. i Control device 60 iThe measurement system control device 530 sends the alignment history data file containing the information of the wafer grid of each wafer received, such as the data of the deformation component of the wafer grid of each wafer received (the data of the model formula (1) after the determination coefficients a0, a1, ..., b0, b1, ...), to the storage device inside each wafer.

[0169] When the measurement of all wafers included in one batch is completed, the measurement system control device 530 sends the wafer grid information (alignment history data file) of each of the plurality of wafers included in the batch to the host computer 2000. It goes without saying that the wafer grid information (alignment history data file) sent from the measurement system 500 also includes data of nonlinear components of the wafer grid.

[0170] Furthermore, the measuring device 100 may also be i Control device 60 i The host computer 2000 is connected via the LAN 1500, and the wafer grid information (alignment history data file) is transmitted from the control device 60 to the control device 60 instead of the measurement system control device 530. i Send to host computer 2000.

[0171] In the above embodiment, the wafer grid information is sent (output) from the measurement system 500, but the information (data) sent from the measurement system is not limited to this. For example, the measurement device 100 may also send (output) the wafer grid information. i The measured coordinate position information of the plurality of wafer marks is transmitted (output) as at least a part of the alignment history data of each wafer.

[0172] As an example, the exposure device 200 constituting a part of the substrate processing system 1000 is a projection exposure device (scanner) of a step-and-scan method. Fig.11 , components within the chamber of the exposure device 200 are partially omitted.

[0173] The exposure device 200 is as follows Fig.11 As shown, the exposure device 200 is provided with an illumination system IOP, a reticle stage RST for holding a reticle R, a projection unit PU for projecting an image of a pattern formed on the reticle R onto a wafer W coated with a sensing agent (resist), a wafer stage WST for holding the wafer W and moving it in an XY plane, and a control system thereof, etc. The exposure device 200 is provided with a projection optical system PL having an optical axis AX in the Z-axis direction parallel to the optical axis AX1 of the mark detection system MDS.

[0174] The illumination system IOP includes a light source and an illumination optical system connected to the light source through a light transmission optical system, and is configured to illuminate the reticle R along the X-axis direction ( Fig.11 The slit-shaped illumination area IAR extending elongatedly (in the direction perpendicular to the paper surface in the image) is illuminated with substantially equal illumination by illumination light (exposure light) IL. The structure of the illumination system IOP is disclosed in, for example, the specification of U.S. Patent Application Publication No. 2003 / 0025890. Here, as the illumination light IL, ArF excimer laser (wavelength 193 nm) is used as an example.

[0175] The reticle stage RST is configured in the illumination system IOP Fig.11 The reticle stage RST is driven by a reticle stage drive system 211 ( Fig.11 Not shown in the figure, refer to Fig.12 ), and can be driven slightly in the horizontal plane (XY plane) on the reticle stage plate (not shown), and can be driven along the scanning direction ( Fig.11 The left and right directions on the paper, i.e. the Y-axis direction) are driven within a predetermined travel range.

[0176] On reticle stage RST, reticle R is placed, and reticle R has a pattern area and a plurality of marks whose positional relationship with the pattern area is known formed on the surface (pattern surface) on the -Z side. The position information of reticle stage RST in the XY plane (including the rotation information in the θz direction) is detected by reticle laser interferometer (hereinafter referred to as "reticle interferometer") 214, through movable mirror 212 (or a reflecting surface formed on the end face of reticle stage RST), for example, always at a resolution of about 0.25 nm. The measurement information of reticle interferometer 214 is supplied to exposure control device 220 (refer to Fig.12 ). Furthermore, the position information of the reticle stage RST in the XY plane may be measured by an encoder instead of the reticle laser interferometer 214.

[0177] The projection unit PU is configured on the reticle stage RST. Fig.11. Projection unit PU includes lens barrel 240 and projection optical system PL held in lens barrel 240. Projection optical system PL is, for example, telecentric on both sides and has a predetermined projection magnification (e.g., 1 / 4, 1 / 5, or 1 / 8, etc.). Reticle R is configured in a manner that the pattern surface is roughly consistent with the first surface (object surface) of projection optical system PL, and wafer W with a resist (sensing agent) coated on the surface is configured on the second surface (image surface) side of projection optical system PL. Therefore, when illumination area IAR on reticle R is illuminated by illumination light IL from illumination system IOP, a reduced image of the circuit pattern of reticle R in the illumination area IAR (a reduced image of a part of the circuit pattern) is formed on an area (hereinafter also referred to as exposure area) IA on wafer W that is conjugate with illumination area IAR by illumination light IL passing through reticle R. Furthermore, by synchronously driving reticle stage RST and wafer stage WST, reticle R is relatively moved along the scanning direction (Y-axis direction) with respect to illumination area IAR (illumination light IL), and wafer W is relatively moved along the scanning direction (Y-axis direction) with respect to exposure area IA (illumination light IL), thereby performing scanning exposure of an irradiation area (division area) on wafer W, and transferring the pattern of reticle R to the irradiation area.

[0178] As the projection optical system PL, for example, a refractive system is used, which only includes a plurality of refractive optical elements (lens elements), for example, about 10 to 20 elements, arranged along an optical axis AX parallel to the Z-axis direction. Among the plurality of lens elements constituting the projection optical system PL, the plurality of lens elements on the object surface side (the graticule R side) are movable lenses, which can be displaced along the Z-axis direction (the optical axis direction of the projection optical system PL) and driven along the tilt direction relative to the XY plane (i.e., the θx direction and the θy direction) by a driving element not shown in the figure, such as a piezoelectric element. In addition, the imaging characteristic correction controller 248 ( Fig.11 Not shown in the figure, refer to Fig.12 ) Based on the instruction from the exposure control device 220, the applied voltage to each driving element is independently adjusted, thereby driving each movable lens individually to adjust various imaging characteristics (magnification, distortion, astigmatism, coma, field curvature, etc.) of the projection optical system PL. Furthermore, instead of or in addition to the movement of the movable lens, the following structure can be used, that is, an airtight chamber is provided between adjacent specific lens elements inside the lens barrel 240, and the imaging characteristic correction controller 248 controls the pressure of the gas in the airtight chamber. It is also possible to adopt a structure in which the imaging characteristic correction controller 248 can shift the central wavelength of the illumination light IL. With these structures, the imaging characteristics of the projection optical system PL can also be adjusted.

[0179] The wafer stage WST is driven by a stage drive system 224 ( Fig.11 For convenience, it is represented by a block in the figure), and is driven on the wafer stage fixed plate 222 with a predetermined stroke along the X-axis direction and the Y-axis direction, and is slightly driven along the Z-axis direction, the θx direction, the θy direction, and the θz direction. On the wafer stage WST, a wafer W is held by a wafer holder (not shown) by vacuum adsorption or the like. In this embodiment, the wafer holder can adsorb and hold a 300 mm wafer. Furthermore, a stage device can be used instead of the wafer stage WST, and the stage device comprises: a first stage that moves along the X-axis direction, the Y-axis direction, and the θz direction; and a second stage that moves slightly along the Z-axis direction, the θx direction, and the θy direction on the first stage. Furthermore, either or both of the wafer stage WST and the wafer holder of the wafer stage WST can be referred to as a "second substrate holding member."

[0180] The position information of wafer stage WST in the XY plane (including rotation information (yaw amount (rotation amount θz in the θz direction), pitch amount (rotation amount θx in the θx direction), roll amount (rotation amount θy in the θy direction))) is detected by laser interferometer system (hereinafter referred to as interferometer system) 218 ​​through movable mirror 216 (or a reflection surface formed on the end face of wafer stage WST), for example, at a resolution of about 0.25 nm. Furthermore, the position information of wafer stage WST in the XY plane can also be measured by an encoder system instead of interferometer system 218.

[0181] The measurement information of the interferometer system 218 is supplied to the exposure control device 220 (see Fig.12 Based on the measurement information of the interferometer system 218 , the exposure control device 220 controls the position of the wafer stage WST in the XY plane (including the rotation in the θz direction) via the stage driving system 224 .

[0182] Again, Fig.11 Although not shown in the figure, the position and tilt of the surface of the wafer W in the Z-axis direction are measured by, for example, a focus sensor AFS (see Fig.12 ) is measured, and the focus sensor AFS includes a multi-point focus position detection system of an oblique incidence method disclosed in the specification of U.S. Patent No. 5,448,332. The measurement information of the focus sensor AFS is also supplied to the exposure control device 220 (refer to Fig.12 ).

[0183] Furthermore, a reference plate FP is fixed on wafer stage WST, and the surface of the reference plate FP is at the same height as the surface of wafer W. A first reference mark used for baseline measurement of alignment detection system AS, a pair of second reference marks detected by a reticle alignment detection system described later, and the like are formed on the surface of the reference plate FP.

[0184] An alignment detection system AS is provided on the side of the lens barrel 240 of the projection unit PU to detect the alignment mark or the first reference mark formed on the wafer W. As the alignment detection system AS, for example, a FIA (Field Image Alignment) system, which is a type of imaging alignment sensor of an image processing method, is used. The FIA ​​system uses broadband (broadband) light such as a halogen lamp to illuminate the mark, and performs image processing on the image of the mark to measure the mark position. Furthermore, a diffraction light interference type alignment system may be used in place of the alignment detection system AS of the image processing method, or together with the alignment detection system AS.

[0185] In exposure device 200, a pair of reticle alignment detection systems 213 ( Fig.11 Not shown in the figure, refer to Fig.12 ), the pair of reticle alignment detection systems 213 can simultaneously detect a pair of reticle marks located at the same Y position on reticle R placed on reticle stage RST. The detection results of the marks by reticle alignment detection system 213 are supplied to exposure control device 220.

[0186] At Fig.12 In FIG. 2 , the input / output relationship of the exposure control device 220 is shown in a block diagram. Fig.12 As shown, in addition to the above-mentioned structure, the exposure device 200 also includes a wafer transfer system 270 connected to the exposure control device 220 for transferring wafers. The exposure control device 220 includes a microcomputer or a workstation, etc., and performs unified control of the entire device including the above-mentioned structure. The wafer transfer system 270 is composed of, for example, a horizontal multi-joint robot.

[0187] return Figure 1Although not shown in the figure, C / D 300, for example, has a coating section for coating a sensing agent (resist) on a wafer, a developing section for developing the wafer, a baking section for performing pre-baking (PB) and post-exposure baking (PEB), and a wafer transport system (hereinafter referred to as the C / D internal transport system for convenience). C / D 300 further has a temperature control section 330 for regulating the temperature of the wafer. The temperature control section 330 is usually a cooling section, for example, having a flat plate (temperature control device) called a cooling plate. The cooling plate is cooled, for example, by the circulation of cooling water. In addition, electronic cooling based on the Peltier effect is sometimes used.

[0188] The overlay measurement device 400 measures the overlay deviation by measuring the relative positional relationship between the first mark transferred during the exposure of the lower layer and the second mark transferred during the exposure of the current layer, and the images (resist images), the first mark and the second mark constituting overlay measurement marks (positioning marks), which are formed together with each shot region on the wafer W that has been developed in the C / D 300. Here, as a set of the first mark image and the corresponding second mark image, for example, a resist image of a frame-in-frame mark including an outer frame mark and an inner frame mark arranged inside the outer frame mark can be used.

[0189] The analysis device 3000 performs various analyses and calculations according to instructions from the host computer 2000. For example, the analysis device 3000 performs calculations according to a predetermined program based on the measurement results of the overlay deviation from the overlay measurement device 400, and calculates correction values ​​for feedback to the exposure device 200.

[0190] In the substrate processing system 1000 of the present embodiment, the measuring device 100 i Similarly, both the exposure device 200 and the C / D 300 are equipped with a barcode reader (not shown) in the wafer transport system 270 (see Fig.12 ) and the C / D internal transport system (not shown) each transport the wafer, and the identification information of each wafer, such as the wafer number, batch number, etc., is appropriately read by the barcode reader. In the following, for the sake of simplicity, the description related to the reading of the identification information of each wafer using the barcode reader is omitted.

[0191] In the substrate processing system 1000, a plurality of wafers are continuously processed by each of the measurement system 500 and the lithography system including the exposure device 200 and the C / D 300. In the substrate processing system 1000, the measurement processing of the measurement target wafer by the measurement system 500 and the processing of the wafer whose measurement by the measurement system 500 has been completed by the lithography system are performed independently of each other. Therefore, there is a limitation that the processing by the lithography system is performed on the wafer whose measurement by the measurement system 500 has been completed, but the overall processing sequence can be specified so that the throughput of the substrate processing system as a whole is maximized.

[0192] Hereinafter, an operation flow in the case where a plurality of wafers are processed continuously by the lithography system including the exposure apparatus 200 and the C / D 300 will be described.

[0193] First, the first wafer (set as W1) is taken out from the wafer carrier arranged in the chamber of C / D300 by the C / D internal transport system (for example, the selective compliance assembly robot arm (SCARA)) and moved into the coating section. Thereby, the coating of the resist is started by the coating section. When the coating of the resist is completed, the C / D internal transport system takes out the wafer W1 from the coating section and moves it into the baking section. Thereby, the heating treatment (PB) of the wafer W1 is started in the baking section. Then, when the PB of the wafer is completed, the C / D internal transport system takes out the wafer W1 from the baking section and moves it into the temperature control section 330. Thereby, the cooling of the wafer W1 is started by using the cooling plate inside the temperature control section 330. The cooling is performed at a temperature that has no effect on the exposure device 200. Generally speaking, for example, the target temperature of the air conditioning system of the exposure device 200 is specified in the range of 20 to 25°C as the target temperature. Normally, when the wafer is loaded into the temperature control unit 330 , the temperature of the wafer is within the range of ±0.3 [° C.] relative to the target temperature, but the temperature is controlled by the temperature control unit 330 to within the range of ±10 [mK] of the target temperature.

[0194] Then, when cooling (temperature control) in the temperature control unit 330 is completed, the wafer W1 is placed on a loading-side substrate placement unit of a substrate transfer unit provided between the C / D 300 and the exposure device 200 by the intra-C / D transfer system.

[0195] In C / D 300, the same series of resist coating, PB, cooling, and wafer transfer operations as described above are repeated in sequence, and the wafers are sequentially placed on the loading side substrate placement unit. In fact, two or more coating units and C / D internal transfer systems are respectively provided in the chamber of C / D 300, thereby realizing parallel processing of multiple wafers, thereby shortening the time required for pre-exposure processing.

[0196] The wafer W1 placed on the loading side substrate placement portion is transported to a predetermined standby position inside the exposure device 200 by the wafer transport system 270. However, the first wafer W1 is not placed in the standby position, but is directly loaded onto the wafer stage WST by the exposure control device 220. The loading of the wafer is controlled by the exposure control device 220 and the measurement device 100. i The above operation is performed by using the unillustrated up-and-down moving member and the wafer transfer system 270 on the wafer stage WST. After loading, the wafer on the wafer stage WST is subjected to the same search alignment as described above, and the EGA method wafer alignment is performed using the alignment detection system AS, for example, setting 3 to 16 irradiation areas as the alignment irradiation areas. During the EGA method wafer alignment, the alignment history data file of the wafer (target wafer) to be the wafer alignment and exposure object in the exposure device 200 is provided from the host computer 2000 to the exposure control device 220 of the exposure device 200 together with the identification information of the target wafer (for example, wafer number, batch number, etc.). The alignment history data acquired by the exposure device 200 from the host computer 2000 includes the information of the wafer grid of each wafer measured by the measurement system 500. After the predetermined preparation operation, the exposure control device 220 performs the wafer alignment as described later according to the information of the measurement mode contained in the acquired alignment history data. Furthermore, the exposure control device 220 and the measurement system control device 530 may exchange alignment history data and the like without going through the host computer 2000 .

[0197] Here, before specifically describing wafer alignment, the reason why EGA-type wafer alignment is performed using the exposure apparatus 200 with about 3 to 16 shot regions as alignment shot regions will be described.

[0198] By measuring device 100 i The obtained correction amount of the position coordinate of the exposure area of ​​the wafer W (the coefficients a0, a1, ..., b0, b1, ... of the above formula (1)) is used, for example, to align the wafer with respect to the exposure position when the wafer W is exposed by the exposure device 200. i The wafer W for which the position coordinate correction amount has been measured is removed from the measuring device 100 as described above. iAfter the slider 10 is unloaded, it is stored in the FOUP 520, and the FOUP 520 is moved into the C / D 300 by other transport systems such as OHT. Then, after the wafer W is coated with resist by the C / D 300, it is placed on the wafer stage WST of the exposure device 200 for exposure. In this case, even if the wafer holder WH on the slider 10 and the wafer holder on the wafer stage WST of the exposure device 200 use the same type of wafer holder, the holding state of the wafer W will be different due to the individual differences of the wafer holder. Therefore, even if the measurement device 100 is used, the wafer W will not be held in the same state. i The correction amount of the position coordinates of the irradiation area of ​​the wafer W (the coefficients a0, a1, ..., b0, b1, ... of the above formula (1)) is obtained, and it is also impossible to directly use all of the coefficients a0, a1, ..., b0, b1, .... However, it can be considered that what is affected by the different holding states of the wafer W by each wafer holder is the low-order component (linear component) below the first order of the position coordinate correction amount of the irradiation area, while the high-order components above the second order are almost unaffected. The reason is that the high-order components above the second order can be considered to be components mainly caused by the deformation of the wafer W caused by the process, so it can be considered to be components unrelated to the holding state of the wafer by the wafer holder.

[0199] Based on this consideration, the measuring device 100 i The coefficients a3, a4, ..., a9, ... and b3, b4, ..., b9, ... of the higher-order components obtained for wafer W in a time-consuming manner may be directly used as the coefficients of the higher-order components of the position coordinate correction amount of wafer W in exposure apparatus 200. Therefore, it is sufficient to perform a simple EGA measurement (for example, measurement of about 3 to 16 wafer marks) for obtaining the linear component of the position coordinate correction amount of wafer W on wafer stage WST of exposure apparatus 200.

[0200] First, the case where the alignment history data file of the target wafer contains information of mode A will be described. In this case, the information contained in the alignment history data by the measurement device 100 i From the wafer marks whose position information is measured (the marked position information is used in the calculation of the correction amount), the wafer marks whose number corresponds to the number of alignment irradiation areas are selected as detection objects, and the wafer marks that are the detection objects are detected using the alignment detection system AS. Based on the detection results and the position of the wafer stage WST during the detection (the measurement information of the interferometer system 218), the position information of each wafer mark that is the detection object is calculated, and the EGA operation is performed using the position information to calculate the coefficients of the following formula (2).

[0201] [Formula 2]

[0202]

[0203] Then, the exposure control device 220 replaces the coefficients (c0, c1, c2, d0, d1, d2) obtained here with the coefficients (a0, a1, a2, b0, b1, b2) contained in the data of the deformation components of the wafer grid of the target wafer, and uses the polynomial represented by the following formula (3) containing the replaced coefficients, which is related to the designed position coordinates X, Y of each irradiation area on the wafer coordinate system with the center of the wafer as the origin, to obtain the correction amount (alignment correction component) dx, dy of the position coordinates of each irradiation area, and based on the correction amount, determines the target position (hereinafter referred to as the positioning target position for convenience) for correcting the wafer grid and for each irradiation area relative to the exposure position (projection position of the reticle pattern) during exposure. Furthermore, in this embodiment, exposure is performed in a scanning exposure method rather than a static exposure method, but for convenience it is referred to as the positioning target position.

[0204] [Formula 3]

[0205]

[0206] Furthermore, in exposure apparatus 200, the rotation of the reference coordinate system (stage coordinate system) and the wafer coordinate system that are required to move wafer stage WST is eliminated by search alignment, and therefore there is no need to specifically distinguish between the reference coordinate system and the wafer coordinate system.

[0207] Next, the case where the alignment history data file of the target wafer contains the information of the B mode is described. In this case, the exposure control device 220 determines the positioning target position of each irradiation area for correcting the wafer grid according to the same process as the case containing the A mode information. However, in this case, the alignment history data includes a plurality of wafer marks for several irradiation areas and a wafer mark for each of the remaining irradiation areas, and the detection signal is a good wafer mark, which is used as the wafer mark for which the mark position information is used in the calculation of the correction amount.

[0208] Therefore, in addition to determining the positioning target position of each of the above-mentioned irradiation areas, the exposure control device 220 also selects the number of wafer marks required to obtain the shape of the irradiation area from the multiple wafer marks related to the above-mentioned several irradiation areas, and uses the position information (measured values) of these wafer marks to perform statistical operations such as applying the least square method to the model formula of [Formula 7] disclosed in the specification of U.S. Patent No. 6,876,946 (also known as multi-point EGA operation within the irradiation area) to obtain the shape of the irradiation area. Specifically, among the 10 parameters in the model formula of [Formula 7] disclosed in the specification of U.S. Patent No. 6,876,946, the wafer rotation (θ), the orthogonality error (w) of the wafer, and the wafer ratio (rx) in the x direction and the wafer ratio (ry) in the y direction are obtained. Furthermore, the multi-point EGA operation within the irradiation area has been disclosed in detail in the above-mentioned U.S. patent, so the detailed description is omitted.

[0209] Then, exposure control device 220 controls the position of wafer stage WST according to the positioning target position, and exposes each irradiation area on wafer W1 in a step-scan manner. Here, when the shape of the irradiation area is also obtained by multi-point EGA measurement in the irradiation area, during the scanning exposure, at least one of the relative scanning angle between reticle stage RST and wafer stage WST, the scanning speed ratio, the relative position of at least one of reticle stage RST and wafer stage WST relative to the projection optical system, the imaging characteristics (aberration) of projection optical system PL, and the wavelength of illumination light (exposure light) IL is adjusted so that the pattern of reticle R is deformed according to the shape of the irradiation area obtained by matching the projection image of projection optical system PL. Here, the adjustment of the imaging characteristics (aberration) of projection optical system PL and the adjustment of the center wavelength of illumination light IL are performed by exposure control device 220 through imaging characteristics correction controller 248.

[0210] Then, before the exposure of the wafer (wafer W1 in this case) on the wafer carrier WST is completed, the second wafer W2 is placed on the loading side substrate loading portion of the substrate conveying portion by the C / D internal conveying system, and is transported to a predetermined standby position inside the exposure device 200 by the wafer conveying system 270, and waits at the standby position.

[0211] Then, when the exposure of wafer W1 is completed, wafer W1 and wafer W2 are exchanged on the wafer stage, and the exchanged wafer W2 is subjected to the same wafer alignment and exposure as above. Furthermore, before the exposure of the wafer on the wafer stage (wafer W1 in this case) is completed, if the transfer of wafer W2 to the standby position is not completed, the wafer stage is made to hold the exposed wafer and wait near the standby position.

[0212] In parallel with the wafer alignment of the exchanged wafer W2 , the wafer W1 after exposure is transferred to the unloading-side substrate placement portion of the substrate transfer unit by the wafer transfer system 270 .

[0213] As mentioned above, the exposed wafer placed on the substrate loading section on the unloading side of the substrate conveying section by the wafer transfer system 270 is moved into the baking section by the C / D internal transfer system, and PEB is performed by the baking device in the baking section. In the baking section, multiple wafers can be accommodated at the same time.

[0214] On the other hand, the wafer after PEB is taken out from the baking section by the C / D intra-transfer system and transported into the developing section, and development is started by the developing device in the developing section.

[0215] Then, when the development of the wafer is completed, the wafer is taken out from the development section by the C / D internal transport system and transported to the FOUP 520 used for transporting, or a predetermined storage means in a different wafer carrier. Afterwards, in the C / D 300, for the second and subsequent wafers that have completed exposure, PEB, development, and wafer transport are repeated in the same process as the wafer W1.

[0216] As described above, according to the substrate processing system 1000 of the present embodiment, the measurement device 100 of the measurement system 500 can be used to measure the substrate independently of the processing operation of the exposure device 200 on the target wafer including the simplified EGA measurement and exposure. i By performing alignment measurement of the target wafer, efficient processing can be achieved without reducing the throughput of wafer processing of the exposure device 200. In addition, as the entire substrate processing system 1000, the exposure device 200 performs alignment measurement of the measurement device 1000 that has been measured by the measurement system 500 in parallel. i The alignment and exposure process of a certain batch of wafers which have been previously measured, and the measuring device 100 of the measuring system 500 i The measurement process of another batch of wafers can also be performed efficiently without causing a decrease in the throughput of wafer processing. i In parallel with the wafer alignment and exposure operation of the exposure device 200 on a certain batch of wafers, full irradiation area EGA with all irradiation areas as sample irradiation areas can be performed on another batch of wafers.

[0217] Furthermore, in the measuring device 100 of the measuring system 500 iIn the embodiment, before the exposure device 200 performs wafer alignment and exposure on the same batch of wafers whose previous process steps (etching, oxidation / diffusion, film formation, ion implantation, planarization (CMP), etc.) have been completed, a full irradiation area EGA (hereinafter collectively referred to as alignment measurement corresponding to the setting of the mode) in which all irradiation areas are set as sampling irradiation areas is first performed to obtain alignment history data including wafer grid information (such as data on deformation components of the wafer grid) for each wafer obtained by the alignment measurement. The alignment history data obtained for each wafer is stored in an internal storage device by the measurement system control device 530 for each wafer. Therefore, in the exposure device 200, the alignment history data including wafer grid information for the target wafer obtained by using the measurement system control device 530 can be effectively used to perform wafer alignment and exposure on the target wafer. That is, it can be said that in the substrate processing system 1000 of the present embodiment, the measuring device 100 of the measuring system 500 i The alignment history data concerning the target wafer obtained by the prior measurement processing in the process, including wafer grid information (eg, data on deformation components of the wafer grid), is substantially forwarded (provided) to the exposure device 200 in a feed-forward manner.

[0218] Furthermore, by the measuring device 100 i The coefficients of the high-order components in the model formula obtained by the full irradiation area EGA in the pre-measurement processing can also be directly used in the exposure device 200. Therefore, in the exposure device 200, it is only necessary to perform alignment measurement with several irradiation areas set as alignment irradiation areas to obtain the coefficients of the low-order components of the above model formula, and then use the coefficients of the low-order components and the coefficients of the low-order components obtained by the measurement device 100. i The coefficients of the obtained high-order components can not only confirm the coefficients (undetermined coefficients) of the low-order components of the model formula (1), but also the coefficients (undetermined coefficients) of the high-order components. The model formula (1) (i.e., the above formula (3)) with the determined undetermined coefficients and the design values ​​(X, Y) of the arrangement of the multiple irradiation areas on the wafer can be used to obtain the correction amount from the designed position of each irradiation area. In this way, the correction amount with the same good accuracy as when the coefficients of the low-order and high-order components of the model formula (1) are obtained using the exposure device 200 can be obtained. In addition, based on the correction amount and the design values ​​of the arrangement of the multiple irradiation areas on the wafer, the positioning target position of each irradiation area during exposure can be calculated. Therefore, by controlling the position of the wafer stage WST according to the target position, each irradiation area can be accurately aligned with respect to the exposure position (the projection position of the reticle pattern). In this way, the output of the exposure device 200 will not be reduced, and the superposition accuracy of the image of the reticle pattern during exposure and the pattern formed in each irradiation area on the wafer can be improved.

[0219] Furthermore, according to the measuring device 100 of this embodiment i , control device 60 i While controlling the movement of the slider 10 by the driving system 20, the first position measuring system 30 and the second position measuring system 50 are used to obtain the position information of the slider 10 relative to the platen 12 and the relative position information of the mark detection system MDS and the platen 12, and the position information of the plurality of marks formed on the wafer W is obtained using the mark detection system MDS. i , the position information of the plurality of marks formed on the wafer W can be obtained with good accuracy.

[0220] Furthermore, according to the measuring device 100 of this embodiment i , control device 60 i The measurement information (relative position information of the fixed plate 12 and the mark detection system MDS) of the second position measurement system 50 is constantly obtained, and the position of the fixed plate 12 in the 6-DOF direction is instantly controlled through the three vibration isolation devices 14 (actuators thereof), so that the positional relationship between the detection center of the mark detection system MDS and the measurement point of the first position measurement system that detects the position information of the slider 10 relative to the fixed plate 12 in the 6-DOF direction is maintained at a desired relationship at the nm level. i While controlling the drive system 20 to drive the slider 10, the measurement information of the first position measurement system 30 (the position information of the slider 10 relative to the platen 12) and the measurement information of the second position measurement system 50 (the relative position information between the platen 12 and the mark detection system MDS) are obtained, and the position information of a plurality of wafer marks is obtained based on the detection signal when the mark detection system MDS is used to detect the mark formed on the wafer W, the measurement information of the first position measurement system 30 obtained when the mark detection system MDS is used to detect the mark formed on the wafer W, and the measurement information of the second position measurement system 50 obtained when the mark detection system MDS is used to detect the mark formed on the wafer W. Therefore, according to the measurement device 100 i , the position information of the plurality of marks formed on the wafer W can be obtained with good accuracy.

[0221] Furthermore, for example, in the case where the EGA operation is not performed using the position information of the measured mark, but the position control of the wafer W (wafer stage WST) during exposure is performed based on the position information of the measured mark, for example, the measurement information of the second position measurement system 50 may not be used for calculating the position information of the mark. However, in this case, the measurement information of the second position measurement system 50 obtained when the mark formed on the wafer W is detected using the mark detection system MDS is used as a compensation value, for example, the positioning target value of the wafer W (wafer stage WST) and other information used to move the wafer W are corrected. Alternatively, the movement of the reticle R (reticle stage RST) during exposure may be controlled in consideration of the compensation value.

[0222] Furthermore, according to the measuring device 100 of this embodiment i The first position measurement system 30 for measuring the position information of the slide 10 carrying and holding the wafer W in the 6-DOF direction uses the mark detection system MDS to detect at least the wafer mark on the wafer W, so that the self-reading head 32 can continuously irradiate the measuring beam to the grating RG1 within the range of movement of the slide 10. Therefore, the first position measurement system 30 can continuously measure the position information within the entire range of the XY plane in which the slide 10 moves to detect the mark. Therefore, for example, in the measuring device 100 i In the manufacturing stage (including the startup stage of the device in the semiconductor manufacturing plant), the origin of the orthogonal coordinate system (reference coordinate system) defined by the length measuring axis of the first position measurement system 30 is found, thereby managing the absolute position of the slider 10 on the reference coordinate system, and even the absolute position of the mark (not limited to the search mark, wafer mark, but also including other marks such as the superposition measurement mark (alignment mark), etc.) on the wafer W held on the slider 10 obtained based on the position information of the slider 10 and the detection result of the mark detection system MDS. Furthermore, in this specification, the so-called "absolute position" refers to the coordinate position on the reference coordinate system.

[0223] As can be clearly understood from the description so far, the substrate processing system 1000 of the present embodiment is provided with the measuring system 500, whereby, even when the exposure device 200 only has the function of performing a simple EGA measurement (for example, obtaining position information of about 3 to 16 wafer marks using the alignment detection system AS) for obtaining the linear component of the position coordinate correction amount of the wafer within a predetermined time (a time allowed in order to maintain the required high throughput), the deformation of the wafer grid can be obtained with high precision using the low-order components of the deformation of the wafer grid obtained by the simple EGA measurement and the high-order components of the deformation of the wafer grid obtained in advance by the measuring system 500, for example, by the full-point EGA. Therefore, the measuring system 500 can substantially improve the grid correction function of the exposure device 200. Therefore, compared with the most advanced exposure device without the grid correction function, the wafer can be exposed with high precision at a high throughput or without reducing the throughput.

[0224] Furthermore, in the substrate processing system 1000 of the above-mentioned embodiment, the measuring device 100 i Although the C / D 300 and the exposure device 200 are provided with a barcode reader, the barcode reader may be replaced with a writing / reading device for a wireless IC tag, i.e., an RFID tag. In this case, by attaching an RFID tag to each wafer, the measurement device 100 i Using a write / read device, the above-mentioned alignment history data is written into the RFID tag for each wafer, and other devices such as the exposure device 200 use a write / read device to read the alignment history data from the RFID tag of the target wafer. In this way, feedforward forwarding of the alignment history data of the above-mentioned target wafer can be easily achieved.

[0225] In the substrate processing system 1000 of the above embodiment, the coefficients of the first-order and lower-order components of the above model formula are obtained for the exposure device 200, and the coefficients of the lower-order components are used together with the coefficients of the first-order components obtained by the measurement device 100. i However, the present invention is not limited to this. For example, the coefficients of the components of the model formula below the second order may be obtained based on the detection results of the alignment marks in the exposure device 200, and the coefficients of the components below the second order may be used together with the coefficients of the components obtained by the measurement device 100. i Alternatively, for example, the coefficients of the components below the third order of the above model formula may be obtained based on the detection results of the alignment marks in the exposure device 200, and the coefficients of the components below the third order and the coefficients of the components obtained by the measurement device 100 may be used. iThat is, the coefficients of the components below the (N-1)th order (N is an integer greater than or equal to 2) of the above model formula can be obtained based on the detection results of the alignment marks in the exposure device 200, and the coefficients of the components below the (N-1)th order and the coefficients of the components obtained by the measurement device 100 can be used. i The coefficients of the Nth-order or higher-order components of the obtained model formula.

[0226] Furthermore, in the above-mentioned embodiment, the measuring device 100 i The coefficients a3, a4, a5 ... and b3, b4, b5 ... of the higher-order components of the second order or higher, and the coefficients a0, a1, a2, b0, b1, b2 of the lower-order components of the first order or lower of the model formula (1) are also obtained. The model formula (1) expresses the relationship between the designed position coordinates X, Y of each irradiation area on the wafer coordinate system (consistent with the reference coordinate system) and the position coordinate correction amount (alignment correction component) dx, dy of the irradiation area. However, since the coefficients of the lower-order components are obtained by using the exposure device 200, the coefficients of the lower-order components are calculated by using the measurement device 100. i There is no need to find the coefficients of the lower-order components.

[0227] Furthermore, in the above-mentioned embodiment, in the measuring device 100 i In the case where the B mode is set in the exposure device 200 and the position information of multiple wafer marks on multiple shot areas on the wafer is measured, the wafer rotation (θ), the orthogonality error (w) of the wafer, and the wafer ratio (rx) in the x direction and the wafer ratio (ry) in the y direction are calculated by multi-point EGA calculation in the shot area, thereby calculating the shape of the shot area. However, this is not limited to this. For example, even if the measurement device 100 i When the A mode is set in the exposure apparatus 200 and the position information of each wafer mark is measured for all the shot regions on the wafer, the exposure apparatus 200 can also estimate the deformation of the shot region (change in shape of the shot region). This will be described below.

[0228] The wafer grid on the wafer W will be deformed due to the process, and each irradiation area will also be slightly deformed due to the process, but it is considered that the deformation will be along the deformation of the wafer grid. The variable components of the wafer grid can be divided into four independent variable components shown below, each of which will cause the irradiation area deformation shown below.

[0229] (1) Variation of dx in the X-axis direction

[0230] X-axis magnification change

[0231] (2) Variation of dx in the Y-axis direction

[0232] Rotation about the Y axis

[0233] (3) The variation component of dy in the X-axis direction

[0234] Y-axis magnification change

[0235] (4) The variation component of dy about the Y axis

[0236] Rotation about the X axis

[0237] Therefore, in the present embodiment, the above-mentioned variation components (1) to (4) are calculated, and the deformation of the irradiation region on the wafer W is estimated based on the variation components.

[0238] In addition, there are roughly two methods as shown below for estimating the deformation of the irradiated area.

[0239] (A) The irradiation area is deformed according to the values ​​obtained by partial differentiation of X and Y in equation (3) after the coefficients (undetermined coefficients) are determined.

[0240] (B) The wafer grid is approximated to a first-order model formula, and the irradiation area is deformed according to the coefficients of the model formula. Here, for the wafer grid, the designed position coordinates X and Y of each irradiation area can be respectively substituted into the formula (3) after the coefficients (undetermined coefficients) are determined, and the correction amount of the arrangement of multiple irradiation areas on the wafer from the designed value (correction amount dx, dy of the position coordinates of the irradiation area), that is, the deformation component of the wafer grid, is calculated using the correction amount and the design value of the position coordinates of the irradiation area.

[0241] Hereinafter, the method of correcting the shape of the irradiation area by the estimation method of (A) is referred to as high-order partial differential correction, and the method of correcting the shape of the irradiation area by the estimation method of (B) is referred to as first-order approximate correction. Even for the same wafer grid, the deformation state of the irradiation area is different when the method of (A) is used and when the method of (B) is used.

[0242] FIG. 13(A) and FIG. 13(B) schematically show an example of the difference between the high-order partial differential correction and the first-order approximate correction. Here, for the sake of simplicity, it is assumed that the Y component dy in the wafer grid is dy=b6·X 3 FIG13(A) shows three irradiation areas corrected by high-order partial differential correction. When high-order partial differential correction is performed, the rotation of each irradiation area relative to the Y axis follows dy=b6·X 3 The partial differential is dy'=3b6·X 2. At this time, the deformation amount of the central irradiation area among the three irradiation areas is 0. On the other hand, FIG13(B) shows the three irradiation areas corrected by the first approximate correction. In the first approximate correction, the EGA method alignment is performed again with the first-order model formula, and the first-order coefficient related to the rotation relative to the Y-axis in the model formula is used to correct the shape of the irradiation area. When the first approximate correction is performed, as shown in FIG13(B), the central irradiation area among the three irradiation areas also undergoes the first deformation, and overall, the deformation of each irradiation area becomes the same.

[0243] As shown in FIG. 13(A) and FIG. 13(B), in the high-order partial differential correction, the deformation of the irradiation area is locally along the wafer grid around the irradiation area, while in the first approximate correction, the deformation of all irradiation areas of wafer W becomes the same. For example, which method to select can be specified according to the exposure recipe, or can be appropriately selected by the user according to the required specifications of the semiconductor to be manufactured. When the deformation of the irradiation area is estimated, as described above, exposure control device 220 adjusts at least one of the relative scanning angle between reticle stage RST and wafer stage WST, the scanning speed ratio, the relative position of at least one of reticle stage RST and wafer stage WST relative to the projection optical system, the imaging characteristics (aberration) of projection optical system PL, and the wavelength of illumination light (exposure light) IL during scanning exposure, so that the pattern of reticle R is deformed by the irradiation area shape obtained by matching the projection image of projection optical system PL (the irradiation area shape obtained by estimating the deformation of the irradiation area).

[0244] Furthermore, in the substrate processing system 1000 of the present embodiment, the measuring device 100 i When the measuring unit 40 has the aforementioned multi-point focal position detection system, the measuring device 100 can also be used. i Wafer alignment measurement and flatness measurement (also called focus mapping) of the wafer W are performed. At this time, by using the result of the flatness measurement, focus and leveling control of the wafer W during exposure can be achieved without the need for flatness measurement by the exposure apparatus 200 .

[0245] Furthermore, at least one of the measuring devices 1001, 1002, and 1003 of the measuring system 500 may be a measuring device having a function different from that of the other measuring devices. For example, one measuring device may be a measuring device having a multi-point focus position detection system for measuring the concavity (flatness) of the wafer surface, or may be a wafer shape measuring device. Furthermore, the measuring system 500 may have two or four or more measuring devices.

[0246] Furthermore, in the above embodiment, the object is set to be a 300 mm wafer, but it is not limited to this, and it can also be a 450 mm wafer with a diameter of 450 mm. i Wafer alignment is performed, so even if the wafer is 450mm, the output of the exposure process will not be reduced, and full-point EGA measurement, for example, can be performed.

[0247] Furthermore, in the above-mentioned embodiment, for the sake of simplicity of description, the measuring device 100 i The measurement mode is to set either A mode or B mode, but B mode may not be set. In addition, the following may be set: for all irradiation areas on all wafers in the batch, a C mode is used to detect two or more wafer marks of the first quantity; and for all wafers in the batch, for a part of the irradiation area, such as a predetermined irradiation area located at the periphery of the wafer, two or more wafer marks of the second quantity are detected, and for the remaining irradiation areas, a mode (called D mode) is used to detect one wafer mark each. Furthermore, an E mode may be set, that is, based on the detection results of the wafer marks of the initial predetermined number of wafers in the batch, one of A mode, C mode, and D mode is selected for the remaining wafers in the batch.

[0248] Furthermore, as the measuring device 100 i The measurement mode can also measure one or more wafer marks of a portion of the irradiation areas, such as 90% or 80% of the irradiation areas, for all wafers in a batch, or, for the irradiation area located in the center of the wafer, measure one or more wafer marks of the irradiation areas that are separated by one.

[0249] Furthermore, in the measuring device 100 of the above embodiment i In the figure, the case where the gratings RG1, RG2a, and RG2b respectively use the X-axis direction and the Y-axis direction as periodic directions is described, but it is not limited to this. As long as the grid parts (two-dimensional gratings) of the first position measurement system 30 and the second position measurement system 50 respectively use the two directions that intersect each other in the XY plane as periodic directions, it will suffice.

[0250] Furthermore, the measuring device 100 described in the above embodiment i The structure is just an example. For example, the measuring device only needs to be configured as follows, that is, it has a stage (slider 10) that can move relative to the base member (fixed plate 12) and can measure the position information of multiple marks on the substrate (wafer) held on the stage. Therefore, the measuring device does not necessarily need to have, for example, the first position measurement system 30 and the second position measurement system 50.

[0251] Furthermore, the configuration of the head unit 32 of the first position measurement system 30 described in the above embodiment and the arrangement of the detection points are of course only examples. For example, the position of the detection point of the mark detection system MDS and the detection center of the head unit 32 may not coincide in at least one of the X-axis direction and the Y-axis direction. Furthermore, the arrangement of the head unit and the grating RG1 (grid unit) of the first position measurement system 30 may be opposite. That is, the head unit may be provided on the slider 10 and the grid unit may be provided on the fixed disk 12. Furthermore, the first position measurement system 30 does not necessarily need to include the encoder system 33 and the laser interferometer system 35, and the first position measurement system 30 may be constituted by only the encoder system. The first position measurement system may also be constituted by the following encoder system, which irradiates the grating RG1 of the slider 10 with a light beam from the head unit and receives the return light beam (diffracted light beam) from the grating to measure the position information of the slider 10 relative to the fixed disk 12 in the 6-degree-of-freedom direction. In this case, the structure of the head of the head section is not particularly limited. For example, a pair of XZ heads that irradiate detection beams to two points that are spaced at the same distance in the X-axis direction relative to a predetermined point on the grating RG1, and a pair of YZ heads that irradiate detection beams to two points that are spaced at the same distance in the Y-axis direction relative to a predetermined point may be provided. Alternatively, a pair of three-dimensional heads that irradiate detection beams to two points spaced apart in the X-axis direction of the grating RG1, and an XZ head or a YZ head that irradiates detection beams to points that are different in position from the above two points in the Y-axis direction may be provided. The first position measurement system 30 does not necessarily need to be able to measure the position information of the slider 10 relative to the fixed plate 12 in the six degrees of freedom directions. For example, it may only be able to measure the position information in the X, Y, and θz directions. Furthermore, the first position measurement system that measures the position information of the slider 10 relative to the fixed plate 12 may also be arranged between the fixed plate 12 and the slider 10. Furthermore, the first measuring system for measuring the aforementioned absolute position of the slider 10 does not necessarily need to include an encoder system that irradiates a light beam from the aforementioned read head portion to the grating RG1 of the slider 10, but may also include an interferometer system or other measuring devices that measure the position information of the slider 10 in the six-degree-of-freedom direction relative to the fixed plate 12 or in the three-degree-of-freedom direction in the horizontal plane.

[0252] Similarly, the configuration of the second position measurement system 50 described in the above embodiment is only an example. For example, the read heads 52A and 52B may be fixed to the side of the fixed disk 12, and the scales 54A and 54B may be provided integrally with the mark detection system MDS. In addition, the second position measurement system 50 is provided with a pair of read heads 52A and 52B, but it is not limited thereto. The second position measurement system 50 may only have one read head, or may have more than three read heads. In short, it is preferable that the positional relationship between the fixed disk 12 and the mark detection system MDS in the six degrees of freedom direction can be measured by the second position measurement system 50. However, the second position measurement system 50 does not necessarily need to be able to measure all the positional relationships in the six degrees of freedom direction.

[0253] Furthermore, in the above-mentioned embodiment, the following situation is described, that is, the slider 10 is suspended and supported on the fixed plate 12 by a plurality of air bearings 18, and a drive system 20 is formed, and the drive system 20 includes a first drive device 20A that drives the slider 10 along the X-axis direction, and a second drive device 20B that drives the slider 10 along the Y-axis direction integrally with the first drive device 20A, and drives the slider 10 in a non-contact state relative to the fixed plate 12. However, this is not limited to this, and as the drive system 20, a drive system that drives the slider 10 along the six-degree-of-freedom directions on the fixed plate 12 may also be used. As an example, the drive system may also be formed by a magnetic levitation type planar motor. In this case, the air bearings 18 are not required. Furthermore, the measuring device 100 i A drive system for driving the surface plate 12 may be provided independently of the vibration isolation device 14 .

[0254] In the above embodiment, the measuring system 500 includes an EFEM system as the carrier system 510, but the EFEM system may be replaced with a carrier storage device that can store multiple (for example, three) carriers (FOUPs, etc.) along the Y-axis direction. In this case, the measuring system 500 may also include: i A plurality of loading ports are respectively arranged adjacent to each other, and a carrier transport device for transporting carriers (FOUP, etc.) between a carrier storage device and the loading portions of the plurality of loading ports.

[0255] 《Second Implementation Form》

[0256] Next, a second embodiment will be described. In this embodiment, wafer grid variation management and overlay measurement performed using the measurement system 500 of the substrate processing system 1000 will be described.

[0257] As described above, the measuring device 100 iThe first position measuring system 30 is provided, and therefore, by finding the origin of the orthogonal coordinate system (reference coordinate system) defined by the length measuring axis of the first position measuring system 30, the absolute position of the slider 10 can be managed on the reference coordinate system, and even the absolute position of the wafer mark such as the overlay measurement mark (alignment mark) on the wafer W held on the slider 10 obtained based on the position information of the slider 10 and the detection result of the mark detection system MDS can be managed. That is, the measuring device 100 can also be used to measure the position of the slider 10. i It functions as a superposition measuring device 400.

[0258] 《Change Management of Wafer Grids》

[0259] Next, a case where a wafer grid management method derived from an exposure device using a measurement device is applied to the substrate processing system 1000 will be described as an example. Fig.14 , the processing flow of the wafer grid management method in this case is schematically shown.

[0260] First, in step S202, exposure device 200 is used to expose bare wafers (for convenience, referred to as wafer W0) contained in a certain batch using product reticle R in a step-by-step scanning manner. Here, it is assumed that on reticle R, on its pattern surface, a mark (transferred to the wafer to become a wafer mark) is formed in its surrounding area or inside the pattern area (when multiple wafers are taken in one irradiation area) together with a rectangular pattern area. Here, wafer W0 is an unexposed wafer, and a resist is coated on its surface by C / D 300. Therefore, when wafer W0 is exposed, alignment is not performed, and based on the design value, the exposure control device 220 drives and controls the reticle stage RST and the wafer stage WST. By exposure in step S202, a number of (for example, 98) rectangular pattern areas arranged in a matrix are formed in the resist layer on the surface of wafer W0, as well as a transfer image (latent image) of a mark corresponding to each irradiation area whose positional relationship with each irradiation area is known in design.

[0261] Then, in step S204, the exposed wafer W0 is unloaded from the wafer stage WST and moved into the developing section of the C / D 300. Specifically, the wafer W0 is transported by the wafer transport system 270 and placed on the unloading side substrate placement section of the substrate transport section provided between the C / D 300 and the exposure device 200. Then, the wafer W0 is moved into the developing section of the C / D 300 by the C / D internal transport system.

[0262] Then, in step S206, the wafer W0 is developed by the developing device of the developing section of the C / D 300. After the development, a resist image of a wafer mark corresponding to each irradiation area (hereinafter referred to as a wafer mark as appropriate) having a positional relationship with each irradiation area known in design and arranged in a matrix is ​​formed on the wafer W0.

[0263] Then, in step S208, the FOUP containing a plurality of wafers of a certain batch including the wafer W0 that has completed development is taken out from the C / D 300 and placed on the loading port 514 of the measurement system 500 using the above-mentioned OHT or the like. That is, the wafer W0 in the FOUP taken out from the C / D 300 is transported to the measurement system 500 before the process treatment (etching treatment, or film forming treatment after etching treatment (including at least one of sputtering treatment, CVD treatment, and thermal oxidation treatment)) performed after the development treatment is performed. The wafer W0 contained in the FOUP is taken out from the FOUP using the robot 516 or the like, and loaded into the measurement device 100 using the transport system 521 or the like. i On the slide 10.

[0264] In the following description, one of the plurality of wafers accommodated in the FOUP is referred to as wafer W0 , but the same processing can be performed on all or part of the plurality of wafers accommodated in the FOUP.

[0265] Then, in step S210, the measuring device 100 i , the above-mentioned one-point measurement of the entire irradiation area is performed on the wafer W0 that has completed the development, and the absolute position coordinates of each wafer mark are obtained. i While measuring the position information of the slide 10 using the first position measurement system 30 (and the second position measurement system 50), the mark detection system MDS is used to detect I wafer marks corresponding to I (for example, 98) irradiation areas respectively, and based on the detection results of each I wafer mark and the absolute position coordinates (X, Y) of the slide 10 when each I wafer mark is detected, the absolute position coordinates (X, Y) of I wafer marks corresponding to I irradiation areas on the wafer W0 are obtained. At this time, the control device 60 i Based on the measurement values ​​of the slider 10 in the θx direction and the θy direction measured by the first position measurement system 30, the Abbe errors in the X-axis direction and the Y-axis direction of the first position measurement system 30 and the measurement values ​​in the X-axis direction and the Y-axis direction of the second position measurement system 50 are used as compensation values ​​to obtain the absolute position coordinates (X, Y) of one wafer mark. In step 210, it is ideal to perform one-point measurement of the entire irradiation area, but it is also possible not to perform detection of wafer marks in a part of the irradiation area.

[0266] Then, in step S212, the control device 60 i Using the obtained absolute position coordinates of the I marks, the change information of the arrangement (wafer grid) of the I shot regions on the wafer W0 is obtained. i Based on the known positional relationship between the wafer mark and the center of the irradiation area, the measured values ​​of the absolute position coordinates (X, Y) of each irradiation area are obtained from the absolute position coordinates of I wafer mark, and based on the data of the difference between the measured values ​​of the absolute position coordinates (X, Y) of each irradiation area and the design values ​​of the position coordinates (X, Y) of each irradiation area, the coefficients a0, a1, ..., b0, b1, ... of the above-mentioned formula (1) are obtained using statistical operations such as the least square method. Here, the obtained coefficients a0, a1, ..., b0, b1, ... are substituted into the formula (1), and the formula (1) after the coefficients are determined is used as the variation information of the wafer grid and stored in the memory inside the measurement system 500 (for example, the control device 60 i , or a storage device inside the measurement system control device 530), or an external storage device.

[0267] Alternatively, the control device 60 i It is also possible to calculate the actual measured values ​​of the absolute position coordinates (X, Y) of each of the I irradiation areas from the absolute position coordinates of I wafer marks based on the known positional relationship between the wafer mark and the center of the irradiation area, and create a mapping, which can be used as the change information of the wafer grid. The mapping includes data on the difference between the actual measured values ​​of the absolute position coordinates (X, Y) of each of the I irradiation areas and the design values ​​of the position coordinates (X, Y) of each irradiation area.

[0268] Furthermore, the measured values ​​of the absolute position coordinates (X, Y) of each irradiation area may be used as the change information of the wafer grid.

[0269] Thereby, the variation of the self-designed value of the wafer grid can be obtained at any time and managed.

[0270] The next step S214 can be performed as needed. In step S214, the control device 60 i The variation information of the self-designed value of the wafer grid obtained in step S210 is compared with the variation information of the wafer grid used as a reference and stored in the memory (or the storage device of the measurement system control device 530) in advance to obtain the difference. For example, the variation amount of the wafer grid from the variation of the wafer grid used as the reference is obtained. By processing this step S214, the error of the arrangement of the irradiation area caused by the error of the stage grid between different exposure devices or the error of the arrangement of the irradiation area caused by the error of the stage grid at different times of the same exposure device can be managed.

[0271] In the former case, before processing step S214, a scanning stepper different from the exposure device 200 is used to expose a bare wafer from a different batch from wafer W0 in the same manner as the aforementioned step S202 using a graticule R. For the exposed wafer, the same processing as steps S204 to S212 is performed to obtain change information of the wafer grid serving as a reference and store it in a memory (or a storage device of the measurement system control device 530).

[0272] In the latter case, before processing step S214, other wafers other than wafer W0 that are included in the same batch as wafer W0 or in a different batch from wafer W0 are exposed using reticle R using exposure device 200 in the same manner as step S202, and the wafer is processed in the same manner as steps S203 to S212, thereby obtaining change information of the wafer grid serving as a reference and storing it in the memory (or the storage device of the measurement system control device 530).

[0273] Furthermore, the measuring device 100 for obtaining the wafer grid variation information of the wafer W0 i The measuring device 100 can be used to obtain the wafer grid variation information as a reference. i The same, but also different.

[0274] As is clear from the above description, the management method of this embodiment can manage the change of the wafer grid caused by the device without using a reference wafer. Therefore, the following various problems when using a reference wafer can be avoided.

[0275] That is, the use of reference wafers will use the reference wafers for multiple exposure devices, which will lead to competition. Reference wafers are usually not just one piece but multiple pieces, so the individual differences between the reference wafers must be guaranteed. In addition, the reference wafer may sometimes be damaged or degraded during use. Furthermore, in the wafer grid management method using the reference wafer, a resist is coated on the surface of the reference wafer and exposed, and then, once the required processing is completed, the resist must be stripped and the reference wafer is cleaned. Due to repeated processes, the surface is sometimes damaged. In addition, traces of the clamp components (pin clamps, etc.) of the wafer holder are formed on the back of the reference wafer, which will cause the adsorption deformation of the reference wafer, thereby causing the wafer grid to deform.

[0276] On the other hand, by not using a reference wafer, there are advantages as described below.

[0277] a. You do not need to worry about the space or serial number of the reference wafer. When you want to measure the change of the wafer grid (to make corrections), you can perform measurement (correction).

[0278] b. Since a bare wafer can be used instead of a reference wafer, quality control can be performed easily.

[0279] c. Product irradiation area mapping and product reticle can be used to manage wafer grids. That is, wafer grids can be managed using superposition measurement marks or alignment marks attached to product reticle. As a result, dedicated reticle for quality management is not required. Moreover, quality management can be performed using product irradiation area mapping itself, and thus, not only the variation of wafer grids caused by errors depending on location can be measured, but also the variation of wafer grids caused by scanning speed or acceleration and all other error factors generated in product exposure operation can be measured. Therefore, by making corrections based on the measurement results, the compromise caused by grid management using reference wafers described below can be completely eliminated.

[0280] a. The so-called grid error is dependent on the coordinates. If the location is the same, the error is the same. If the location is near the point where the mark is measured and the grid error correction is performed, the error is considered to be small.

[0281] b. Errors in scanning speed or scanning acceleration will not cause grid errors. Even if grid errors occur, they will not change during each scan, so a single adjustment is sufficient without the need for regular maintenance.

[0282] Furthermore, the information of the wafer grid of wafer W0 obtained in step 212 can also be provided (feedback) to exposure device 200, and after the batch including wafer W0, for bare wafers included in a batch different from wafer W0, when reticle R is used in exposure device 200 for exposure processing, the movement control of stage WST of exposure device 200 is performed to reduce the variation (deviation from the design value) of the first layer wafer grid. That is, the wafer grid information of wafer W0 obtained in step 212 can be used to determine the positioning target position when exposing each irradiation area to bare wafers included in other batches.

[0283] Furthermore, in step 210, the absolute position coordinates of more than two wafer marks can be obtained for all irradiation areas on wafer W0. When information related to the shape and size of each irradiation area can be obtained, the information can also be provided (feedback) to exposure device 200 to control imaging characteristic correction controller 248, or to control at least one of the speed and direction of reticle stage RST, so that the shape and size of each irradiation area are in a desired state.

[0284] Furthermore, in order to perform exposure processing of the second layer (setting the first layer as the upper layer of the lower layer), the change information of the wafer grid of wafer W0 can also be obtained before wafer W0 is moved into C / D device 300 (or other C / D devices) after various processes (including etching processing and film forming processing). At this time, as described in the first embodiment, the alignment history data of wafer W0 including the obtained wafer grid change information can be provided (feedforward) to exposure device 200 or other exposure devices that perform exposure processing of the second layer, and the wafer grid change information of wafer W0 can also be provided (feedback) to exposure device 200, so as to be used after the batch including wafer W0, when the bare wafers contained in the batch different from wafer W0 are exposed by exposure device 200 using reticle R.

[0285] "Superposition Measurement"

[0286] Next, a case where the overlay measurement method using the measurement device is applied to the substrate processing system 1000 is described as an example. Fig.15 The processing flow in the superposition measurement method in this case is schematically shown.

[0287] First, in step S302, wafers contained in a batch (set as wafer W 11 ) is moved into C / D 300, and in the coating section of C / D 300, the wafer W having been exposed to the first layer (lower layer) by the exposure device 200 or an exposure device different from the exposure device 200, such as a scanner or a stepper, is exposed. 11 , and the resist is applied. 11 By exposing the lower layer, a wafer mark having a known positional relationship with the shot region by design and a first mark for measuring the overlay deviation (to be precise, a resist image of the first mark (also appropriately referred to as the first mark image)) is formed corresponding to each shot region together with a plurality of, for example, I (I is, for example, 98) shot regions by exposure of the lower layer. At this time, the positional relationship of each of the I first mark images by design is also known.

[0288] Then, in step S304, the wafer W coated with the resist 11 After the same predetermined processing as the wafer W1, the wafer W is loaded onto the wafer stage WST of the exposure device 200. 11 After being subjected to a heat treatment (PB) in the baking section and temperature control in the temperature control section 330 , the wafer is loaded onto the wafer stage WST.

[0289] Next, in step S306, the exposure control device 220 of the exposure device 200 controls the wafer W on the wafer stage WST. 11, the same search alignment as described above is performed using the alignment detection system AS, and wafer alignment using the EGA method with, for example, 3 to 16 irradiation areas as alignment irradiation areas.

[0290] Furthermore, before step S302, as described in the first embodiment, the measuring device 100 of the measuring system 500 is used. i Find the wafer W 11 The information of the wafer grid is provided to the exposure control device 220 of the exposure device 200.

[0291] Then, in step S308, the exposure control device 220 calculates the correction amounts (alignment correction components) dx and dy of the position coordinates of each irradiation area represented by the aforementioned formula (3) based on the result of wafer alignment, and determines the positioning target position of each irradiation area during exposure for correcting the wafer grid based on the correction amounts.

[0292] Furthermore, before step 302, the measuring device 100 of the measuring system 500 may not be used. i Find the wafer W 11 The positioning target position of each irradiation area during exposure is determined based only on the result of wafer alignment using an alignment detection system AS using, for example, 3 to 16 irradiation areas as alignment irradiation areas, without using the information of the wafer grid.

[0293] Then, in step S310, the exposure device 200 controls the position of the wafer stage WST according to the positioning target position, and simultaneously performs step-scanning on the wafer W. 11 The exposure device 200 uses the exposure area on the wafer W to expose the second layer (the first layer is set as the upper layer of the lower layer). 11 The first mark image on the image is formed with a second mark reticle (for convenience, referred to as reticle R 11 ) is exposed. Therefore, by exposing the second layer, the wafer W 11 I irradiation area on the transfer reticle R overlapped 11 pattern area, and forms a transfer image of I second marks arranged in a positional relationship corresponding to the positional relationship of I first marks.

[0294] Then, in step S312, the wafer W having the second layer exposed is 11 After the same processing as the wafer W1 after exposure, the wafer W is moved into the developing section of the C / D 300. 11The wafer is transported to the unloading side substrate loading section of the substrate conveying section by the wafer transport system 270, and is transported from the unloading side substrate loading section to the baking section of the C / D 300 by the C / D internal transport system, and PEB is performed by the baking device in the baking section. 11 The product is taken out from the baking section by the C / D internal transport system and transported into the developing section.

[0295] Next, in step S314, the wafer W having the transferred images of the plurality of second marks formed thereon is subjected to a developing device in the developing unit. 11 By this development, the wafer W 11 On the substrate, together with one irradiation area, a set of one first mark image and a corresponding second mark image is formed in a predetermined positional relationship, thereby becoming a substrate to be measured during superimposition measurement. That is, a substrate to be measured during superimposition measurement (superimposition measurement target substrate) is produced in this way. Here, as a set of the first mark image and the corresponding second mark image, for example, a resist image of a frame-in-frame mark can be used, and the frame-in-frame mark includes an outer frame mark and an inner frame mark arranged inside the outer frame mark.

[0296] Then, in step S316, the wafer W containing the developed wafer is received. 11 A FOUP of a plurality of wafers of a certain batch (substrates to be measured by stacking) is taken out from C / D 300 and placed on the load port 514 of the measurement system 500 using the above-mentioned OHT or the like. That is, the wafers W in the FOUP taken out from C / D 300 are 11 Before the process treatment (etching treatment or film forming treatment after etching treatment (including at least one of sputtering treatment, CVD treatment, and thermal oxidation treatment)) is performed after the development treatment, the wafer W is transported to the measurement system 500. 11 The robot 516 is used to take the sample out of the FOUP and the transfer system 521 is used to transfer the sample to the measuring device 100. i .

[0297] In the following, one of the plurality of wafers housed in the FOUP is referred to as wafer W. 11 Although this is described above, the same processing may be performed on all or part of the plurality of wafers accommodated in the FOUP.

[0298] Then, in step S318, the measuring device 100 i , the developed wafer W is transported 11 The (superimposed measurement target substrate) is loaded onto the slide 10 in the above process, and the absolute position coordinates of each of the first and second marker images of the I group in the XY plane are obtained in the following manner. iWhile measuring the position information of the slider 10 using the first position measuring system 30 (and the second position measuring system 50), the mark detection system MDS detects the positions of the wafers W. 11 Based on the detection results of each of the first marker image and the second marker image and the absolute position coordinates (X, Y) of the slide 10 when each marker image is detected, the wafer W is obtained. 11 The absolute position coordinates of the first marker image and the second marker image on the XY plane. i Based on the measurement values ​​of the slide 10 in the θx direction and the θy direction measured by the first position measurement system 30, the Abbe errors in the X-axis direction and the Y-axis direction of the first position measurement system 30 and the measurement values ​​in the X-axis direction and the Y-axis direction of the second position measurement system 50 are used as compensation values ​​to calculate the absolute position coordinates of I first marker images and I second marker images in the XY plane.

[0299] Furthermore, in step S318, the absolute position coordinates of K first marker images and the absolute position coordinates of K second marker images, which are less than I, can also be calculated.

[0300] Then, in step S320, the control device 60 i Based on the absolute position coordinates of the first marker image and the absolute position coordinates of the second marker image that form a group with each other, the superposition error (superposition deviation) between the first layer and the second layer is calculated.

[0301] Then, in step S322, the control device 60 i Based on the absolute position coordinates of the first marker image and the absolute position coordinates of the second marker image, it is determined whether the superposition error is mainly caused by the exposure of the first layer or the exposure of the second layer, for example, in the following manner. i Calculate the deviation (ΔX1) of the absolute position coordinates of the first marker image from the designed position coordinates. i , ΔY1 i )(i=1 to I), and the deviation of the absolute position coordinates of the second marker image from the designed position coordinates (ΔX2 i , ΔY2 i )(i=1~I), for ΔX1 i , ΔX2 i , ΔY1 i , ΔY2 i Find the sum ΣX1 of i=1~I respectively i ,ΣX2 i ,ΣY1 i ,ΣY2 i Furthermore, the control device 60 i At ΣX1i >ΣX2 i And ΣY1 i >ΣY2 i In the case of ΣX1, it is judged that the superposition error in both the X-axis direction and the Y-axis direction is mainly caused by the exposure of the first layer. i <ΣX2 i And ΣY1 i <ΣY2 i In the case of , it is determined that the superposition error in both the X-axis direction and the Y-axis direction is mainly caused by the exposure of the second layer. i At ΣX1 i >ΣX2 i And ΣY1 i <ΣY2 i In the case of ΣX1, it is judged that the overlay error is mainly caused by the exposure of the first layer in the X-axis direction and mainly caused by the exposure of the second layer in the Y-axis direction. i <ΣX2 i And ΣY1 i >ΣY2 i In the case of , it is judged that the overlay error is mainly caused by the exposure of the second layer with respect to the X-axis direction, and is mainly caused by the exposure of the first layer with respect to the Y-axis direction.

[0302] Furthermore, the above determination method is only an example. In short, the control device 60 i As long as the overlay error is mainly caused by the exposure of the first layer or the exposure of the second layer, it is determined based on the absolute position coordinates of I first mark images and the absolute position coordinates of I second mark images, and the specific determination method is not particularly limited.

[0303] The wafer W obtained by the above-mentioned overlay measurement method 11 The data of the superimposition error (superimposition deviation) and the data of the judgment result of whether the superimposition error is mainly caused by the exposure of the first layer or the exposure of the second layer are fed back to the control device 60. i , or at least one of the exposure device for exposing the first layer and the exposure device 200 for exposing the second layer is controlled by the measurement system control device 530.

[0304] For example, when the main cause of the overlay error is the exposure of the first layer, the data can also be fed back to the exposure device for the first layer. 11 The wafers contained in different batches are compared with the wafer W 11 In the case of the same exposure processing for the first layer, the positioning target position can be determined based on the feedback data so as to reduce the superposition error with the second layer.

[0305] Furthermore, when the main cause of the overlay error is the exposure of the second layer, the data can also be fed back to the exposure device 200 for the second layer. 11 The wafers contained in different batches are compared with the wafer W 11 In the case of the same exposure processing for the second layer, the positioning target position can be determined based on the feedback data so as to reduce the superposition error with the first layer.

[0306] Furthermore, data feedback can also be performed through the host computer 2000.

[0307] Furthermore, in step 318, the wafer W may be 11 In the case where the absolute position coordinates of two or more marks are obtained for all the irradiation areas on the first layer, and the first information related to the shape and size of each irradiation area of ​​the first layer and the second information related to the shape and size of each irradiation area of ​​the second layer can be obtained, the first information can be provided (fed back) to the exposure device that exposes the first layer, and the second information can be provided (fed back) to the exposure device 200 that exposes the second layer. At this time, the imaging characteristic correction controller 248 can be controlled, or at least one of the speed and direction of the reticle stage RST can be controlled, so that the shape and size of each irradiation area of ​​the second layer become the desired state.

[0308] Furthermore, in the above description, the superposition error (superposition deviation) between the first layer and the second layer is obtained based on the absolute position coordinates of the first marker image and the absolute position coordinates of the second marker image, but the data of the absolute position coordinates of the first marker image and the data of the absolute position coordinates of the second marker image may be outputted from the measurement system 500 as information of the superposition error (position deviation) between the first layer and the second layer. In this case, the data outputted from the measurement system 500 may be provided (fed back) to at least one of the exposure device (exposure device 200 or other exposure device) that performs exposure of the first layer and the exposure device 200 that performs exposure of the second layer.

[0309] Furthermore, the positional deviations of the first marker image and the second marker image, which are a set of each other, can be respectively calculated based on the absolute position coordinates of the first marker image and the absolute position coordinates of the second marker image, and the data of the positional deviations can be outputted from the measurement system 500 as information of the superposition error between the first layer and the second layer (the positional deviation between the first layer and the second layer). In this case, the data outputted from the measurement system 500 can be provided (fed back) to at least one of the exposure device (exposure device 200 or other exposure device) that performs exposure of the first layer and the exposure device 200 that performs exposure of the second layer.

[0310] As is clear from the above description, according to the overlay measurement method performed by the substrate processing system 1000 of the second embodiment, the measurement system 500 can measure the absolute position coordinates of the first mark image and the absolute position coordinates of the second mark image, respectively, and can measure the overlay error based on the absolute position coordinates. In addition, an excellent effect not available in the past can be obtained, that is, it can be determined whether the overlay error is mainly caused by the exposure of the lower layer or the exposure of the upper layer.

[0311] Furthermore, in the above description, the overlay deviation measurement marks (first mark image and second mark image) are used to obtain the overlay error between the first layer and the second layer, but wafer marks (alignment marks) may also be used. That is, the overlay error between the first layer and the second layer may also be obtained based on the absolute position coordinates of one wafer mark on the first layer and the absolute position coordinates of one wafer mark on the second layer.

[0312] Furthermore, in the above step S320, the overlay error (overlay deviation) between the first layer and the second layer has been calculated, so step S322 only needs to be executed as needed.

[0313] In the above description, after the exposure process of the second layer, the measuring device 100 of the measuring system 500 is used. i , obtain the wafer W that has completed development 11 The absolute position coordinates of the first mark image (or the wafer mark of the first layer) and the absolute position coordinates of the second mark image (or the wafer mark of the second layer) can be measured by using the measuring device 100 of the measuring system 500 after the exposure process of the first layer and before the exposure process of the second layer. i Get the wafer W that has been developed 11 The absolute position coordinates of the first mark image (or the wafer mark of the first layer) are measured by the measuring device 100 of the measuring system 500 after the exposure process of the second layer. i Get the wafer W that has been developed 11 At this time, the superposition error between the first layer and the second layer can be obtained by the measurement system 500 (control device 60 i , 530), or may be obtained by other devices (such as the host computer 2000). In addition, the measuring device 100 for obtaining the absolute position coordinates of the first mark image (or the first layer of wafer mark) i , and a measuring device 100 for acquiring the absolute position coordinates of the second mark image (or the second layer of wafer mark) i It can also be different.

[0314] Furthermore, in order to perform exposure processing of the next layer of the second layer, the wafer W may be 11After various processes (including etching and film forming) and before being carried into the C / D device 300 (or other C / D devices), the wafer W 11 The measuring device 100 of the measuring system 500 is used to carry the measuring device 100 of the measuring system 500. i , get wafer W 11 The absolute position coordinates of the first mark image (or the wafer mark of the first layer) and the absolute position coordinates of the second mark image (or the wafer mark of the second layer), or the absolute position coordinates of the wafer W 11 In this case, the measurement system 500 can be used to obtain the superposition error between the first layer and the second layer (the position deviation between the first layer and the second layer), or the measurement system 500 can be provided with the information of the absolute position coordinates obtained by the measurement system 500, and the superposition error between the first layer and the second layer (the position deviation between the first layer and the second layer) can be obtained by other devices (such as the host computer 2000). In addition, the information of the superposition error between the first layer and the second layer (the position deviation between the first layer and the second layer) obtained by the measurement system 500 or the information of the absolute position coordinates obtained by the measurement system 500 can also be provided to the exposure device 200 or other exposure devices.

[0315] Furthermore, in the above description, the measurement system 500 is used to obtain the information of the overlay error between the first layer and the second layer, but the present invention is not limited thereto, and the overlay error between the mth layer (lower layer, m is an integer greater than 1) and the nth layer (upper layer, n is an integer greater than m and greater than 2) may also be obtained. In this case, the nth layer may not be the layer below the mth layer.

[0316] Furthermore, in the second embodiment, the measuring device 100 for managing the variation of the wafer grid i Measuring device 100 for overlay measurement i It can also be different.

[0317] Furthermore, in the substrate processing system 1000 of the second embodiment, both the wafer grid variation management and the overlay measurement are performed, but only one of them may be performed.

[0318] In the substrate processing system 1000 of the second embodiment, the measurement system 500 is not connected to either the exposure device 200 or the C / D device 300, but may be connected to one or both of the exposure device 200 and the C / D device 300. For example, the C / D device 300 may be arranged between the exposure device 200 and the measurement system 500, and the C / D device 300 and the measurement system 500 may be connected to each other online. Alternatively, the measurement system 500 may be arranged between the exposure device 200 and the C / D device 300, and the measurement system 500 may be connected to both of the exposure device 200 and the C / D device 300 online. In this case, the measurement system 500 may not include the carrier system 510.

[0319] In the first and second embodiments, the measurement system 500 may not include a plurality of measurement devices 100. i That is, the measurement system 500 may include one measurement device, for example, only the measurement device 1001 .

[0320] Furthermore, in the first and second embodiments (hereinafter referred to as the embodiments), the following cases are described: i The signal processing device 49 that processes the detection signal of the mark detection system MDS (i=any one of 1 to 4) sends only the measurement results of the wafer marks whose waveforms of the detection signals obtained as the detection results of the mark detection system MDS are good to the control device 60. i , whereby the control device 60 i The EGA operation is performed using the measurement results of the wafer marks. As a result, the exposure control device 220 performs the EGA operation using a part of the position information of the wafer marks selected from the plurality of wafer marks whose detection signal waveforms obtained as the detection results of the mark detection system MDS are good. However, the present invention is not limited to this. The signal processing device 49 may also send the measurement results of the remaining wafer marks except for the wafer marks whose detection signal waveforms obtained as the detection results of the mark detection system MDS are bad to the control device 60. i Furthermore, the signal processing device 49 may be replaced by the control device 60 i The control device 60 determines whether the detection signal obtained as the detection result of the mark detection system MDS is good. i The EGA operation is performed using only the measurement results of the wafer marks other than the wafer marks whose detection signals are judged to be good or the wafer marks whose detection signals are judged to be bad. iThe measurement results of the wafer marks of the EGA operation are selected from a portion of the measurement results of the wafer marks for which the aforementioned EGA operation is performed.

[0321] Furthermore, in the above-mentioned embodiments, the case where the C / D 300 is connected to the exposure device 200 is described, but a coating device (coating machine) that coats a sensing agent (resist) on a substrate (wafer) may be connected to the exposure device 200 instead of the C / D 300. In this case, the exposed wafer will be carried into a developing device (developing machine) that is not connected to the exposure device. Alternatively, a developing device (developing machine) that develops the exposed substrate (wafer) may be connected to the exposure device 200 instead of the C / D 300. In this case, a wafer pre-coated with a resist at another location is carried into the exposure device.

[0322] In the above embodiments, the exposure device is described as a scanning stepper, but the invention is not limited thereto. The exposure device may be a static exposure device such as a stepper, or a reduced projection exposure device of a stepping and splicing method that combines irradiation areas with irradiation areas. Furthermore, the above embodiments may also be applied to a multi-stage exposure device having a plurality of wafer stages, as disclosed in, for example, U.S. Patent No. 6,590,634, U.S. Patent No. 5,969,441, and U.S. Patent No. 6,208,407. Furthermore, the exposure device is not limited to the aforementioned dry exposure device that performs exposure of the wafer W without liquid (water), and may be, for example, a liquid immersion exposure device that performs exposure of a substrate with liquid as described in European Patent Application Publication No. 1420298, International Publication No. 2004 / 055803, International Publication No. 2004 / 057590, U.S. Patent Application Publication No. 2006 / 0231206, U.S. Patent Application Publication No. 2005 / 0280791, U.S. Patent No. 6,952,253, etc. Furthermore, the exposure device is not limited to an exposure device for semiconductor manufacturing, and may be, for example, a liquid crystal exposure device that transfers a liquid crystal display element pattern to a square glass plate.

[0323] Semiconductor components are manufactured through a lithography step, which uses an exposure device that constitutes a part of the substrate processing system of each embodiment to expose a photosensitive object using a reticle (photomask) with a pattern, and develop the exposed photosensitive object. In this case, high-integration components can be manufactured with good yield.

[0324] Furthermore, in addition to the lithography steps, the manufacturing process of semiconductor components may also include steps for designing the functions and performances of the components, steps for making a marking film (mask) based on the design steps, component assembly steps (including cutting steps, bonding steps, packaging steps), inspection steps, etc.

[0325] Reference numerals:

[0326] 10: Slide

[0327] 12: Fixing

[0328] 14: Vibration isolation device

[0329] 16: Base frame

[0330] 18: Air bearing

[0331] 20: Drive system

[0332] 20A: 1st drive unit

[0333] 20B: Second drive unit

[0334] 22a, 22b: Movable parts

[0335] 23a, 23b: Movable parts

[0336] 24: Movable stage

[0337] 25a, 25b: Fixing parts

[0338] 26a, 26b: Fixing parts

[0339] 28A, 28B: X-axis linear motor

[0340] 29A, 29B: Y-axis linear motor

[0341] 30: 1st position measurement system

[0342] 32: Read the header

[0343] 33: Encoder system

[0344] 35a~35d:Laser interferometer

[0345] 37x: X reading head

[0346] 37ya, 37yb: Y reader

[0347] 40: Measurement unit

[0348] 48: Vibration isolation device

[0349] 50: Second position measurement system

[0350] 52A, 52B: Read the header

[0351] 58X1, 58X2: XZ reader

[0352] 58Y1, 58Y2: YZ reading head

[0353] 60 i : Control device

[0354] 70 i :Wafer transport system

[0355] 530: Measurement system control device

[0356] 100 i :Measuring device

[0357] 200: Exposure device

[0358] 300: C / D

[0359] 330: Temperature Control Department

[0360] 500: Measurement system

[0361] 510: EFEM system

[0362] 512: EFEM ontology

[0363] 514: Loading port

[0364] 516: Robot

[0365] 521: Transport system

[0366] 524: Loading and transporting components

[0367] 526: Unloading transport components

[0368] 1000: Substrate processing system

[0369] MDS: Mark Detection System

[0370] RG1: Grating

[0371] RG2a, RG2b: Grating

[0372] W: Wafer

[0373] WST: Wafer Stage

Claims

1. A substrate processing system for a micro-component production line, characterized in that: include: A measurement system comprising a first measurement device, the first measurement device acquiring position information of a plurality of marks formed on a substrate, the first measurement device acquiring position information of a plurality of marks formed on an m-th layer (m is an integer greater than or equal to 1) of the substrate through exposure and development processing; as well as An exposure device including a substrate stage, the substrate stage carrying the substrate on which the measurement of the position information of the plurality of marks by the first measuring device has been completed, and performing an alignment measurement for acquiring the position information of a selected portion of the plurality of marks on the substrate, and an exposure operation for exposing the substrate using an energy beam, for the substrate carried on the substrate stage; Using the position information of the plurality of marks acquired by the first measuring device, first information related to the arrangement of a plurality of divisional regions formed on the substrate corresponding to the plurality of marks is obtained; Using the position information of the part of the marks obtained by the alignment measurement, obtaining second information related to the arrangement of the plurality of division areas on the substrate; Based on the first information and the second information, the position of the substrate stage when the exposure device performs an exposure operation of the substrate is controlled.

2. The substrate processing system according to claim 1, wherein: The acquisition of the position information of the plurality of marks formed on the m-th layer on the substrate by the first measuring device is performed before the process of performing the process on the m-th layer; The process includes at least one of an etching process and a film forming process.

3. The substrate processing system according to claim 1, wherein: Also includes: A coating device connected in line with the exposure device and coating the induction agent on the substrate, or a coating and developing device coating the induction agent on the substrate and developing the exposed substrate; The first measuring device included in the measuring system acquires the position information of the plurality of marks formed on the mth layer on the substrate before the sensing agent is applied to form the nth layer (n is an integer greater than m and equal to or greater than 2).

4. The substrate processing system according to claim 1, wherein: The first information includes a nonlinear deformation component of an arrangement of the plurality of divisional regions on the substrate.

5. The substrate processing system according to claim 1, wherein: The second information includes a linear deformation component of an arrangement of the plurality of divisional regions on the substrate.

6. The substrate processing system according to claim 1, wherein: Using the position information of the plurality of marks obtained by the first measuring device and a model formula composed of a polynomial of a first predetermined degree, the relationship between the arrangement of the plurality of divisional areas on the substrate and the correction amount of the reference value is obtained; The exposure device uses the position information of the partial mark obtained by the alignment measurement and utilizes a model formula composed of a polynomial of a second predetermined order to obtain a relationship between the correction amount of the arrangement of the plurality of division areas on the substrate and a reference value.

7. The substrate processing system according to claim 6, wherein: The plurality of divisions are formed in a matrix configuration on the substrate, and the correction amount of the arrangement of the plurality of divisions is obtained based on a model formula composed of polynomials related to X and Y, and the polynomials related to X and Y represent the relationship between the design position coordinates X and Y of each division in a substrate coordinate system and the correction amount of the position coordinates of the division, and the substrate coordinate system is a two-dimensional orthogonal coordinate system with a predetermined reference point on the substrate as the origin and the column direction of the matrix, i.e., the X-axis direction, and the row direction, i.e., the Y-axis direction, as the axial directions; The first measuring device obtains the coefficients of the higher-order terms of the model formula by statistical calculation; The exposure device obtains the coefficients of the low-order terms of the model formula by statistical calculation, and obtains the correction amount for the arrangement of the multiple division areas on the substrate based on the model formula after the coefficients of the low-order terms and the high-order terms are substituted into the model formula.

8. The substrate processing system according to claim 7, wherein: The above-mentioned low-order terms are terms of order 1 or less, and the above-mentioned high-order terms are terms of order 2 or more.

9. The substrate processing system according to claim 7, wherein: The exposure device estimates the deformation of the plurality of divisional regions according to the values ​​obtained by partially differentiating X and Y with respect to the model formula after the coefficients are determined.

10. The substrate processing system according to claim 7, wherein: The exposure device calculates the arrangement of the plurality of division areas on the substrate, i.e., a grid, based on the calculated correction amount and the design value of the arrangement of the plurality of division areas on the substrate, approximates the grid to a first-order model formula, and estimates the deformation of the plurality of division areas according to the coefficients of the model formula.

11. The substrate processing system according to claim 9, wherein: The exposure device is a device as described below, that is, a mask stage holding a mask having a pattern formed thereon is moved synchronously with the substrate stage relative to the projection optical system to perform scanning exposure for transferring the pattern to the plurality of divided areas on the substrate; During the scanning exposure, the exposure device adjusts at least one of the relative scanning angle between the mask stage and the substrate stage, the scanning speed ratio, the relative position of at least one of the mask stage and the substrate stage relative to the projection optical system, the imaging characteristics of the projection optical system, and the wavelength of the exposure light, so that the projection image of the pattern by the projection optical system is deformed to match the deformed shapes of the multiple divided areas inferred.

12. The substrate processing system according to claim 1, wherein: The first measuring device may be configured to have a plurality of measurement modes in which detection conditions for detecting the mark are different from each other when obtaining the position information of the mark.

13. The substrate processing system according to claim 11, wherein: The above-mentioned multiple measurement modes include at least one mode among the first mode, the second mode and the third mode, the first mode is to detect one mark for each of all the divided areas on the above-mentioned substrate, the second mode is to detect two or more marks of the first quantity for each of all the divided areas on the above-mentioned substrate, and the third mode is to detect two or more marks of the second quantity for a part of the divided areas on the above-mentioned substrate, and detect one mark for each of the remaining divided areas.

14. The substrate processing system according to claim 12, wherein: The plurality of measurement modes include a fourth mode for setting one of the plurality of measurement modes based on measurement results of a predetermined number of substrates including a first substrate to be processed initially when a plurality of substrates are processed continuously.

15. The substrate processing system according to claim 12, wherein: The plurality of measurement modes include a mode in which, when a plurality of substrates are continuously processed, based on measurement results of a predetermined number of substrates including a first substrate to be processed initially, marks to be detected by the mark detection system are determined for the remaining substrates.

16. The substrate processing system according to claim 12, wherein: When the position information of the plurality of marks is measured by the first measuring device for at least a part of the plurality of divided regions on the substrate, When performing the above-mentioned alignment measurement, the above-mentioned exposure device measures the position information of multiple marks selected from the multiple marks on the above-mentioned substrate, and uses the measured position information of the multiple marks to perform operations including statistical operations to infer the deformation of the above-mentioned divided area. The multiple marks on the above-mentioned substrate include the above-mentioned multiple marks whose position information is measured by the above-mentioned measuring device for at least a part of the divided area on the above-mentioned substrate.

17. A method for manufacturing a component, characterized in that: include: An act of exposing a substrate using an exposure device constituting a part of the substrate processing system according to any one of claims 1 to 16; as well as The exposed substrate is developed.

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