Exposure device and exposure method

Abstract

The present invention provides an exposure device and an exposure method. The exposure device (3) includes: a plurality of light irradiation units (4) that independently irradiate light to different left and right positions on the surface of a substrate (W) to form a strip-shaped irradiation area (30) from one end to the other end of the surface of the substrate; a rotating mechanism (34) that rotates the substrate placed on the carrier relative to the irradiation area; and a moving mechanism (36) for the carrier that moves the carrier relative to the irradiation area. Then, the substrate is rotated relative to the irradiation area forming a first illumination distribution to expose the entire surface of the substrate. In addition, the substrate is moved relative to the irradiation area forming a second illumination distribution in the front-to-back direction while the rotation of the substrate is stopped to expose the entire surface of the substrate.

Description

Technical Field

[0001] The present invention relates to a technique for exposing the entire surface of a substrate. Background Art

[0002] In the photolithography step, which is one of the manufacturing steps of a semiconductor device, there is a case where the entire surface of a semiconductor wafer (hereinafter referred to as a wafer) serving as a substrate is subjected to an exposure process. For example, Patent Document 1 describes forming a resist film on the surface of a wafer using a resist called a photosensitive chemically amplified resist, then exposing the resist film by exposure using a pattern mask, and then exposing the entire surface of the wafer. By exposing the entire surface of the wafer (collective exposure), the acid increases in the area of ​​the resist film exposed by the pattern mask, and by heating and developing treatments performed after the collective exposure, the area is dissolved to form a resist pattern. Exposure of the entire surface of the wafer is performed by arranging a plurality of LEDs (light emitting diodes) that irradiate light downwards in a horizontal manner and moving the wafer in the front-to-back direction below the LED array.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2015-156472 Summary of the invention

[0006] The technical problem that the invention is intended to solve

[0007] According to the exposure amount of the above-mentioned simultaneous exposure, the size CD (Critical Dimension) of the resist pattern formed after development changes. Therefore, a technology for controlling the exposure amount of each part of the wafer in order to make the CD consistent within the wafer surface is studied. However, as described in detail in the embodiment of the present invention, in the photolithography step, there are multiple main factors that act in a different way on each part of the wafer surface to make the CD different. Then, the pattern of the influence of each main factor on the CD distribution within the wafer surface is different, so the distribution of the exposure amount required within the wafer surface becomes complicated.

[0008] The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a technology capable of controlling the exposure amount of each portion within the surface of a substrate with high accuracy in an exposure device that exposes the entire surface of a substrate.

[0009] Technical solutions for solving technical problems

[0010] The exposure device of the present invention is characterized by comprising:

[0011] a mounting portion for mounting a substrate;

[0012] A plurality of light irradiation units independently irradiate light to different positions on the left and right sides of the surface of the substrate to form a strip-shaped irradiation area from one end to the other end of the surface of the substrate;

[0013] A rotating mechanism that rotates the substrate placed on the placement portion relative to the irradiation area;

[0014] a placing portion moving mechanism that moves the placing portion back and forth relative to the irradiation area; and

[0015] A control unit outputs a control signal to execute the following steps:

[0016] The first step is to rotate the substrate relative to the irradiation area formed with the first illumination distribution to expose the entire surface of the substrate; and

[0017] In the second step, while the rotation of the substrate is stopped, the substrate is moved relative to the irradiation area formed with the second illumination distribution in the front-rear direction to expose the entire surface of the substrate.

[0018] The exposure method of the present invention is characterized by comprising:

[0019] a step of placing a substrate on a placing portion;

[0020] A step of independently irradiating light to different left and right positions on the surface of the substrate by a plurality of irradiation units to form a strip-shaped irradiation unit extending from one end to the other end of the surface of the substrate;

[0021] A step of rotating the substrate placed on the placement portion relative to the irradiation region formed with the first illumination distribution to expose the entire surface of the substrate; and

[0022] The step of moving the substrate placed on the placement portion in a front-rear direction relative to the irradiation region formed with a second illumination distribution to expose the entire surface of the substrate.

[0023] The storage medium of the present invention stores a computer program used in an exposure device for exposing a substrate, wherein the storage medium is characterized in that:

[0024] The above-mentioned computer program is compiled into a set of steps to execute the exposure method of the present invention.

[0025] Effects of the Invention

[0026] According to the present invention, a first illumination distribution is formed in a band-shaped illumination area formed by a plurality of light irradiation parts, and the substrate is rotated relative to the illumination area to expose the entire surface of the substrate. In addition, a second illumination distribution is formed in the illumination area, and the substrate is moved in the front-rear direction relative to the illumination area in a state where the rotation of the substrate is stopped to expose the entire surface of the substrate. Thus, it is possible to control with high precision so that the exposure amount of each part of the substrate becomes the desired exposure amount. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a plan view of a coating and developing device using the exposure device of the present invention.

[0028] Figure 2 It is a longitudinal sectional side view of the above-mentioned coating and developing device.

[0029] Figure 3 It is a longitudinal sectional side view of a collective exposure module provided in the coating and developing device.

[0030] Figure 4 FIG. 4 is a cross-sectional plan view of the above-mentioned combined exposure module.

[0031] Figure 5 It is a block diagram showing the structure of the unit provided in the said collective exposure module.

[0032] Figure 6 It is a side view of the above-mentioned unit and the irradiation area constituted by the unit.

[0033] Figure 7 is a plan view of a wafer showing CD distribution.

[0034] Figure 8 It is a plan view of a wafer showing the distribution of exposure amount corresponding to the above-mentioned CD distribution.

[0035] Fig. 9 It is a plan view of a wafer showing the distribution of exposure amount corresponding to the above-mentioned CD distribution.

[0036] Fig.10 FIG. 1 is a diagram showing the operation of wafer processing in the batch exposure module.

[0037] Fig.11 FIG. 1 is a diagram showing the operation of wafer processing in the batch exposure module.

[0038] Fig.12 FIG. 1 is a diagram showing the operation of wafer processing in the batch exposure module.

[0039] Fig.13 is a plan view of a wafer showing CD distribution.

[0040] Fig.14 FIG. 1 is a diagram showing the operation of wafer processing in the batch exposure module.

[0041] Description of Reference Numerals

[0042] W chip

[0043] 10. Control Unit

[0044] 3 Expose modules together

[0045] 33 loading platform

[0046] 34 Rotating mechanism

[0047] 36 Moving mechanism for loading part

[0048] Unit 4

[0049] 40 light source units

[0050] 47LED. DETAILED DESCRIPTION

[0051] Regarding the coating and developing device 1 using the present invention, refer to the plan view and the schematic longitudinal cross-sectional view. Figure 1 , Figure 2 The coating and developing device 1 is constructed by connecting the carrier block D1, the processing block D2 and the interface block D3 horizontally and linearly. For convenience, the direction of the blocks D1 to D3 is the Y direction, and the horizontal direction orthogonal to the Y direction is the X direction. The interface block D3 is connected to the exposure device D4. The carrier block D1 has a carrier C loading portion 11, and the carrier C accommodates a wafer W of a circular substrate. Fig.12 For the opening and closing part, Fig.13 It is a transport mechanism for transferring wafers W between the carrier C and the processing block D2.

[0052] The processing block D2 is formed by stacking unit blocks E1 to E6 for performing liquid processing on wafers W in order from below, and the unit blocks E1 to E6 transfer and process wafers W in parallel with each other. The unit blocks E1 and E2 are configured similarly to each other, the unit blocks E3 and E4 are configured similarly to each other, and the unit blocks E5 and E6 are configured similarly to each other.

[0053] Here, refer to Figure 1E5 is described as a representative of the unit blocks. On one side of the left and right sides of the transport area 14 from the carrier block D1 to the interface block D3, a plurality of shelf units U are arranged in the front-to-back direction, and on the other side, two developing modules 21 are arranged side by side in the Y direction. The developing module 21 supplies a developer to the resist film formed on the surface of the wafer W. The shelf unit U has a heating module 22 for heating the wafer W and a simultaneous exposure module 3. The simultaneous exposure module 3 forms an exposure device of the present invention, and exposes the entire surface of the wafer W. The exposure of the entire surface is exposed at a time. The detailed structure of the simultaneous exposure module 3 will be described later. In addition, a transport arm F5 as a transport mechanism for the wafer W is provided in the above-mentioned transport area 14, and is provided in each block of the unit block E5 and in the towers T1 and T2 described later to transport the wafer W between the unit block E5 and the modules set at the same height.

[0054] Unit blocks E1 to E4 are constructed in the same manner as unit blocks E5 and E6, except that they supply different chemical solutions to wafer W. Unit blocks E1 and E2 include an anti-reflection film forming module that supplies chemical solutions for forming an anti-reflection film to wafer W instead of the developing module 21. Unit blocks E3 and E4 include a resist film forming module that supplies a resist called a photosensitive chemically amplified resist as a chemical solution to wafer W to form a resist film. Figure 2 In FIG. 1 , the transfer arms of the respective unit blocks E1 to E6 are indicated by F1 to F6 .

[0055] On the carrier block D1 side of the processing block D2, there are provided a tower T1 extending vertically across the unit blocks E1 to E6 and a transfer arm 15 as a freely elevating transfer mechanism for transferring wafers W to and from the tower 1. The tower T1 is composed of a plurality of modules stacked one on another, including a transfer module TRS for placing wafers W.

[0056] The interface block D3 includes towers T2, T3, and T4 extending vertically across the unit blocks E1 to E6, and is provided with an interface arm 17 as a freely elevating transport mechanism for transferring wafers W between towers T2 and T3, and an interface arm 18 for transferring wafers W between tower T2 and exposure device D4. Exposure device D4 uses a pattern mask to expose the surface of wafer W by, for example, extreme ultraviolet (EUV). That is, unlike the collective exposure module 3, a portion of wafer W is exposed in a limited manner. Exposure performed by exposure device D4 is sometimes recorded as pattern exposure to distinguish it from collective exposure performed by collective exposure module 3.

[0057] The tower T2 is composed of a transfer module TRS, a buffer module for storing and retaining a plurality of wafers W before exposure processing, a buffer module for storing a plurality of wafers W after exposure processing, and a temperature adjustment module SCPL for adjusting the temperature of the wafers W, etc., which are stacked one on another. Here, the buffer module and the temperature adjustment module are omitted. In addition, the towers T3 and T4 are also provided with molecular modules, and the description thereof is omitted here.

[0058] The transport path of the wafer W in the system composed of the coating and developing device 1 and the exposure device D4 is described. The wafer W is transported from the carrier 11 to the delivery module TRS0 of the tower T1 in the processing block D2 by the transport mechanism 13. From the delivery module TRS0, the wafer W is distributed and transported to the unit blocks E1 and E2. For example, when the wafer W is delivered to the unit block E1, the wafer W is delivered from the above-mentioned delivery module TRS0 to the receiving module TRS1 (a delivery module that can deliver the wafer W through the transport arm F1) corresponding to the unit block E1 among the delivery modules TRS of the tower T1. In addition, when the wafer W is delivered to the unit block E2, the wafer W is delivered from the above-mentioned TRS0 to the delivery module TRS2 corresponding to the unit block E2 among the delivery modules TRS of the tower T1. The delivery of the above-mentioned wafer W is performed by the delivery arm 15.

[0059] The chip W distributed in this way is transported in the order of transfer module TRS1 (TRS2) → anti-reflection film forming module → heating module → transfer module TRS1 (TRS2), and then distributed to the transfer device TRS3 corresponding to the unit block E3 and the transfer device TRS4 corresponding to the unit block E4 through the transfer arm 15.

[0060] The wafer W distributed to the transfer modules TRS3 and TRS4 in the above manner is transferred from the transfer module TRS3 (TRS4) to the resist film forming module, and a photosensitive chemical amplification type resist is applied to the entire surface to form a resist film. Then, the wafer W is transferred in the order of the heating module → the transfer module TRS of the tower T2. Thereafter, the wafer W is transferred to the exposure device D4 through the tower T3 by using the interface arms 16 and 18, and the resist film is pattern-exposed. Acid and photosensitizer are generated in the area where the pattern is exposed.

[0061] After the pattern exposure, the wafer W is transported between the towers T2 and T4 through the interface arms 16 and 17, and is transported to the transfer modules TRS51 and TRS61 of the tower T2 corresponding to the unit blocks E5 and E6, respectively. Then, the entire surface of the wafer W is exposed by the collective exposure module 3, and the above-mentioned photosensitizer absorbs light, and further acid and photosensitizer are generated in the area where the pattern is exposed. That is, by performing collective exposure, the acid is limitedly increased in the area where the pattern is exposed. Then, the wafer W is transported to the heating module 22 and heated. The so-called post-exposure bake (PEB) is performed.

[0062] The area exposed by the PEB pattern is modified by the acid to be soluble in the developer. Next, the wafer W is transported to the developing module 21, and the developer is supplied (to the wafer W), and the modified area is dissolved in the developer to form a resist pattern. After that, the wafer W is transported to the transfer modules TRS5 and TRS6 of the tower T1, and then returned to the carrier 11 by the transport mechanism 13.

[0063] Next, refer to Figure 3 The longitudinal side view and Figure 4 The collective exposure module 3 provided in the above-mentioned unit block E5 is explained with reference to the cross-sectional side view of FIG. 31 in the figure is a frame, and a wafer transfer port 32 is opened in the side wall of the frame 31. A circular mounting table (mounting part) 33 for horizontally mounting the wafer W is provided in the frame 31. The above-mentioned transport arm F5 transfers the wafer W to the mounting table 33 in a manner that the central axes of the wafers W are aligned with each other. The mounting table 33 adsorbs and holds the mounted wafer W.

[0064] In the figure, 34 is a rotating mechanism provided below the mounting table 33. The rotating mechanism 34 has a motor, and the mounting table 33 is rotated by the motor so that the wafer W mounted on the mounting table 33 rotates around the central axis. In the figure, 35 is a support table, which supports the rotating mechanism 34 from below. In the figure, 36 is a moving mechanism for the mounting portion including a motor and a ball screw. The ball screw is rotated by the motor, and the above-mentioned support table 35 connected to the ball screw is horizontally moved forward and backward together with the mounting table 33. During the period of collective exposure of the wafer W described later, the mounting table 33 is horizontally moved at a constant speed, for example.

[0065] By moving the support table 35, the mounting table 33 moves between the following positions: a transfer position closer to the transfer port 32 in the frame 31, where the wafer W is transferred by the transfer arm F5; and an orientation adjustment position farther from the transfer port 32 in the frame 31, where the orientation of the wafer W is adjusted as described later. Figure 3 In the figure, the loading platform 33 is shown at the handover position. Figure 4 In the following description, in the moving direction of the mounting table 33, the side of the handover position is referred to as the front side, and the side of the mounting table 33 facing the adjustment position is referred to as the rear side.

[0066] An illumination unit 38 and a light receiving unit 39 are provided at the rear side in the housing 31, and the illumination unit 38 and the light receiving unit 39 constitute a detection unit for detecting a notch-shaped notch N formed on the periphery of the wafer W. The illumination unit 38 and the light receiving unit 39 are provided so as to sandwich the periphery of the wafer W placed on the stage 33 at the orientation adjustment position, and light is irradiated from the illumination unit 38 to the light receiving unit 39 during the rotation of the wafer W by the stage 33. During the rotation, the control unit 10 described later detects the notch N based on the amount of light received by the light receiving unit 39. Based on a control signal output from the control unit 10 constituting an orientation adjustment mechanism, the rotation mechanism 34 rotates to adjust the orientation of the wafer W so that the detected notch N faces a predetermined direction.

[0067] A light source unit 40 is provided above the moving path of the wafer W formed by the above-mentioned loading portion moving mechanism 36. The light source unit 40 includes a housing 41, a shutter 44, a support substrate 46, and an LED group 48. The lower portion of the housing 41 is configured as a horizontal plate 42 that covers the moving path of the wafer W in the front-rear direction formed by the loading portion moving mechanism 36. An exposure opening 43 extending in the left-right direction is provided in the center portion in the front-rear direction of the horizontal plate 42, and the shutter 44 is provided on the horizontal plate 42. The shutter 44 is moved between a closed position for closing the exposure opening 43 and an open position for opening the exposure opening 43 on the rear side of the closed position by a shutter moving mechanism 45 provided in the housing 41.

[0068] A support substrate 46 is horizontally arranged above the exposure opening 43 in the housing 41. A plurality of LEDs 47 (light emitting diodes) are supported downward on the lower surface of the support substrate 46 so as to irradiate ultraviolet light with a wavelength of, for example, 365 nm. The LEDs 47 are arranged in a row and column of 4×89, for example. The number of LEDs arranged in the front-to-back direction is 4, and the number of LEDs arranged in the left-to-right direction is 89. However, Figure 4 In the figure, for the convenience of illustration, only about 20 LEDs 47 are arranged in the left and right directions. Hereinafter, the LEDs 47 arranged in rows and columns are collectively recorded as an LED group 48. By irradiating the ultraviolet light from the LED group 48, a band-shaped ultraviolet light irradiation area is formed at a height position on the surface of the wafer W placed on the mounting table 33.

[0069] In the LED group 48, four LEDs 47 arranged in a row in the front-to-back direction constitute one unit. In order to distinguish the units from each other, sometimes the unit 4 is indicated as a hyphen and a number from 1 to 89. The numbers are indicated in order from one side to the other. Figure 5, further describing the unit 4 as the light irradiation unit, each unit 4 is connected to, for example, a power source 23 provided outside the frame 31 via a current adjustment unit 49, and the current adjustment unit 49 adjusts the current supplied from the power source 23 to the LED 47 in each unit 4. The larger the supplied current, the larger the amount of light output from the unit 4. In addition, during the operation of the collective exposure module 3, light is usually output from, for example, the LED group 48.

[0070] Figure 6 The irradiation area 30 and the unit 4 are shown as seen in the front-back direction. The dot-dash line in the figure indicates the optical path of the ultraviolet light irradiated by each unit 4, and the irradiation angle of the LED 47 constituting the unit 4 is, for example, less than 100°. Figure 6 As shown, the ultraviolet light irradiated from each unit 4 spreads in the left-right direction as it goes downward, and an arbitrary position of the wafer W is irradiated with ultraviolet light from a plurality of units 4 and exposed.

[0071] As described above, by controlling the current supplied to each unit 4 individually and controlling the amount of light from each unit 4, it is possible to adjust the illuminance distribution in the left and right direction of the irradiation area 30. The batch exposure process is performed by moving the wafer W in the front-back direction relative to the irradiation area 30 in which the illuminance distribution is appropriately set. That is, by adjusting the illuminance distribution of the irradiation area 30, it is possible to adjust the exposure amount of each part of the wafer W. A region with a larger exposure amount generates more acid, so the CD of the pattern becomes larger.

[0072] In addition, in the simultaneous exposure module 3, as Figure 3 As shown, a control unit 10 composed of a computer is provided. The control unit 10 has a program not shown in the figure. Each program includes a step group, and the step group can send a control signal to each part of the collective exposure module 3 to perform exposure of the wafer W described later. Specifically, through the program, the rotation of the mounting table 33 by the rotating mechanism 34, the front-back movement of the mounting table 33 by the mounting part moving mechanism 36, the detection of the notch N by the lighting unit 38 and the light receiving unit 39, the opening and closing of the shutter 44 by the shutter moving mechanism 45, and the adjustment of the illumination distribution of the irradiation field 30 by the current adjustment unit 49 can be implemented. The program is stored in a storage medium such as an optical disk, a hard disk, an MO (magneto-optical disk), a memory card, etc. and installed in the control unit 10.

[0073] In addition, even as described in the above-mentioned project of the problem to be solved by the invention, the CD in the surface of the wafer W deviates from the set value due to various factors involved in the wafer W. As one of the factors, there is a factor that acts as follows: when the wafer is viewed in a straight line from one end to the other end, a relatively large deviation is formed with respect to the size of the CD, and when the wafer is viewed in a direction orthogonal to the straight line, there is no deviation or the deviation becomes relatively small with respect to the size of the CD. This factor is factor 1. As a specific example of this factor 1, when the wafer is heated by each heating module after resist coating to the development position, the heating temperature deviates when viewed from the wafer diameter direction.

[0074] In addition, as another main factor, there is a main factor that acts as follows: when viewed along the peripheral direction of the wafer W, there is no or relatively small deviation in the size of the CD, and when viewed along the diameter of the wafer W, the deviation in the size of the CD is relatively large. That is, according to this main factor, regions with the same or substantially the same size of CD are arranged in concentric circles. This main factor is main factor 2. As a specific example of this main factor 2, it can be cited that the film thickness of the resist film formed by the spin coating method deviates along the diameter direction of the wafer W, and regions with the same or substantially the same film thickness form a film thickness distribution arranged in concentric circles. In more detail, it can be cited that due to such a difference in the film thickness of each part of the wafer W, the amount of acid generated in the resist of each part of the wafer W is different.

[0075] Figure 7 The upper part of is a diagram schematically showing the CD distribution of the resist pattern in the surface of the wafer W when it is assumed that only the above-mentioned main factor 1 and only the main factor 2 act respectively, based on the exposure amount of each part in the surface of the wafer W exposed at the same time being uniform. The CD distribution formed by only the main factor 1 is explained as a straight line distribution, and the CD distribution formed by only the main factor 2 is explained as a concentric circle CD distribution. In addition, the Figure 7 The upper part and the following Figure 7 In the lower part of FIG. 1 , the region in the surface of the wafer W where the CD is less than the set value and has a large deviation is indicated by a gray scale, and each region is indicated by a symbol 51 to 53 according to the density of the gray scale. The gray scale becomes lighter in the order of regions 53, 52, and 51, and the deviation of the CD from the set value is small. In addition, the region 50 without a gray scale is a region where the CD deviation is relatively small.

[0076] As described above, both the main factor 1 and the main factor 2 actually act on the wafer W, and the CD deviation due to the main factor 1 and the CD deviation due to the main factor 2 overlap within the surface of the wafer W. Therefore, when the exposure amount of each part within the surface of the wafer W is uniform based on the collective exposure, for example Figure 7. However, even in such a complex CD distribution, since it is a CD distribution in which the linear CD distribution and the concentric circle CD distribution overlap as described above, it is possible to perform a batch exposure so as to form a distribution of exposure amounts in which CD deviations are eliminated in the linear CD distribution, and before or after the batch exposure, it is possible to perform a batch exposure so as to form a distribution of exposure amounts in which CD deviations are eliminated in the concentric circle CD distribution, thereby performing processing. That is, by performing the batch exposure twice, it is possible to achieve uniformity of all CDs in the surface of the wafer W. Then, in each part in the surface of the wafer W, the exposure amounts by the two batch exposures are added up to a desired amount, and the CD of each part is made to a desired size.

[0077] The following will describe the collective exposure for the linear CD distribution and the concentric circle distribution. As described above, the illumination distribution in the longitudinal direction (left-right direction) of the irradiation area 30 can be adjusted. Therefore, as the collective exposure for the linear CD distribution, by appropriately setting the illumination distribution, the wafer W is moved in the front-back direction relative to the irradiation area 30 while the orientation of the wafer W is fixed in a predetermined orientation. When the orientation is fixed as described above and the collective exposure is made non-rotating collective exposure, the distribution of the exposure amount in the left-right direction of the wafer W in the non-rotating collective exposure corresponds to the illumination distribution in the left-right direction of the irradiation area 30, and therefore, the deviation of the CD in the linear CD distribution can be eliminated within the surface of the wafer W.

[0078] In addition, as the batch exposure for the concentric circle CD distribution, the batch exposure is performed by rotating the wafer W based on the above-mentioned illumination distribution and moving the wafer W in the front-rear direction relative to the irradiation area 30. When the batch exposure performed by rotating the wafer W as described above is called the rotation batch exposure, in the rotation batch exposure, the exposure amount in the axial direction of the wafer W can be made uniform by rotating the wafer W, and the exposure amounts of each part in the radial direction of the wafer W can be made different from each other. Therefore, within the surface of the wafer W, the deviation of the CD in the above-mentioned concentric circle CD distribution can be eliminated.

[0079] exist Figure 8 , Fig. 9 In the plan view of the wafer W, Figure 7 When a straight CD distribution and a concentric circle CD distribution are formed, each shows an example of the distribution of exposure amount formed in the surface of the wafer W in order to eliminate the CD deviation in each CD distribution. Figure 8 , Fig. 9 In FIG. 1 , it is shown that the exposure amount of the areas 55 and 56 marked with gray scale is larger than that of the area 57 not marked with gray scale, and the exposure amount of the area 55 with dark gray scale is larger than that of the area 56 with light gray scale. Figure 8 , Fig. 9 In FIG. 1 , below the wafer W indicated by the gray scale as described above, the irradiation region 30 is indicated in such a manner that the left and right positions correspond to the action positions of the wafer W. Figure 8 , Fig. 9 , a graph showing an example of the illuminance distribution of the irradiation area 30 for forming the distribution of the exposure amount in the surface of the wafer W is also shown. The vertical axis of the graph is illuminance (unit: W / cm). When explained in more detail, the illuminance is the illuminance (unit: W) from one end to the other end of the short side direction of the irradiation area 30 at any position in the longitudinal direction of the irradiation area 30 / the length of the short side of the irradiation area 30 (unit: cm). Each position of the horizontal axis of the graph corresponds to each position in the longitudinal direction of the irradiation area 30 shown on the graph.

[0080] In addition, in both non-rotational exposure and rotational exposure, the front-to-back movement speed of the stage 33 affects the exposure amount of the wafer, so the movement speed is set to obtain a suitable exposure amount. Specifically, (illuminance (W / cm)) / (movement speed (cm / sec)) = exposure amount (J / cm 2 ), the illumination in this formula is Figure 8 , Fig. 9 The vertical axis of the graph shows the illuminance. Figure 8 , Fig. 9 The exposure amount required for the non-rotating batch exposure and the exposure amount required for the rotating batch exposure shown in , the moving speed of the mounting table 33 and the left and right illumination distribution of the irradiation area 30 are obtained by performing preliminary experiments, for example.

[0081] Next, refer to Figure 10 to Figure 12 The batch exposure of the wafer W in the batch exposure module 3 will be described in order. In this description, it is assumed that the exposure amounts of the various portions within the surface of the wafer W are batch exposed so as to be uniform. Figure 7 The wafer W having the CD distribution illustrated in the lower part is exposed together.

[0082] First, with the shutter 44 in the closed position, the amount of light output from each unit 4 is adjusted to form Fig. 9 Then, when the wafer W is transferred to the mounting table 33 at the transfer position by the transfer arm F5, the shutter 44 moves to the open position to form a Fig. 9 Then, the wafer W moves backward while rotating, and the surface of the wafer W passes through the irradiation area 30 and is rotated and exposed at the same time, so that a luminous flux is formed in the surface of the wafer W. Fig. 9 The distribution of exposure shown in .

[0083] When the entire surface of the wafer W is exposed and the stage 33 moves to the adjustment position, the shutter 44 moves to the closed position. Then, the amount of light output from each unit 4 is adjusted to form Figure 8 On the other hand, light is irradiated from the illuminating unit 38 to the light receiving unit 39 while the wafer W is rotating. From the start of the light irradiation by the illuminating unit 38, the wafer W rotates once, and the direction of the notch N of the wafer W is detected based on the amount of light received by the light receiving unit 39 during the one rotation ( Fig.11 ).

[0084] Then, when the wafer W rotates and the notch N faces a predetermined direction, the rotation of the wafer W stops. Then, the shutter 44 moves to the open position, forming a wafer with Figure 8 The illumination area 30 of the illumination distribution diagram is shown in FIG. 1 , and the wafer W moves forward and passes through the illumination area 30, and is exposed simultaneously without rotation, so that a non-rotational exposure is formed in the surface of the wafer W. Figure 8 The distribution of exposure shown ( Fig.12 Then, the shutter 44 moves to the closed position, and when the mounting table 33 is located at the transfer position, the wafer W is carried out from the batch exposure module 3 by the transfer arm F5.

[0085] According to the batch exposure module 3, the wafer W is rotated and moved backward to perform rotational batch exposure through the irradiation area 30 below the units 4 arranged in the left-right direction, and then the wafer W is moved forward in a state where the rotation is stopped to perform non-rotational batch exposure through the irradiation area 30. As a result, the exposure amount of each part in the surface of the wafer W can be controlled so that the influence of the above-mentioned key factor 1 and main factor 2 that act in a manner that the CD deviates from the set value in different patterns is eliminated. That is, it is possible to perform fine and high-precision control so that the exposure amount of each part in the surface of the wafer W becomes the desired amount. As a result, the uniformity of the CD of the resist pattern in each part in the surface of the wafer W after development can be improved.

[0086] However, the above-mentioned non-rotational exposure and rotational exposure are not limited to being performed once each time. For example, if the above-mentioned main factor 1 is applied multiple times, each main factor 1 may sometimes act on the CD, resulting in a large deviation in different directions of the wafer. Fig.13 In, with Figure 7 Similarly, the linear CD distribution formed by the plurality of principal factors 1 as described above is represented by a gray scale. In this example, when the wafer W is viewed from two different directions A1 and A2, the principal factor 1 acts in a manner that changes the size of the CD. A1 and A2 are directions around the center of the wafer W that differ by 90° from each other.

[0087] If the Fig.13As shown in FIG. 1 , the exposure of the wafer when the main factor 1 acts on the wafer is described. First, Fig.13 In order to remove the influence of the omitted main factor 2, Fig.10 As shown in FIG. 1 , the rotating wafer W is moved backward and passes through the irradiation area 30, thereby performing rotation and exposure. Fig.11 The orientation of the wafer W is adjusted as shown in FIG. 1 so that the orientation of the direction A2 is consistent with the front-rear direction. Then, an irradiation area 30 having an illumination distribution in which the influence of the main factor of the direction A1 is eliminated is formed, and the wafer W is moved forward while the rotation of the wafer W is stopped, as shown in FIG. Fig.12 The first non-rotation exposure is performed in the manner described in . Fig.14 The upper side of shows the first non-rotation exposure.

[0088] Furthermore, the wafer W is then rotated 90°. Then, the irradiation region 30 having an illumination distribution in which the influence of the main factor in the direction A2 is eliminated is formed, and the wafer W is moved backward while the rotation of the wafer W is stopped. That is, the wafer W is moved backward in a state different from the orientation of the wafer W relative to the irradiation region 30 in the first non-rotational batch exposure, and the second non-rotational batch exposure is performed. Fig.14 The lower side shows the second non-rotational collective exposure. By performing the non-rotational collective exposure multiple times, the exposure amount in each part within the surface of the wafer W can be controlled more finely. In addition, the rotational collective exposure can also be performed multiple times like the non-rotational collective exposure.

[0089] In each of the above examples, non-rotational exposure is performed after rotational exposure, but rotational exposure may also be performed after non-rotational exposure. In addition, rotational exposure is not limited to being performed by rotating the chip W while moving it in the front-to-back direction. For example, the chip W is moved in the front-to-back direction while the exposure opening 43 is closed by the shutter 44 so that it is located below the exposure opening 43. In a state where the front-to-back movement of the chip W is stopped at this position, the chip W is rotated and the exposure opening 43 is opened to form an irradiation area 30 on the diameter of the chip W. Then, after the entire surface of the rotating chip W is exposed, the exposure opening 43 is closed. Rotational exposure may also be performed in the manner described above. However, the center portion of the chip W is irradiated with light from more units 4 than the peripheral portion, and therefore, the amount of light of each unit 4 irradiating the center portion of the chip W is set to be relatively small. In addition, as Fig.10 In the rotating batch exposure described in the above, in order to prevent the exposure amount of the center portion of the wafer W from increasing as described above, the batch exposure is performed by rotating the wafer W while moving it in the front-rear direction relative to the irradiation area 30.

[0090] In addition, for example, an orientation adjustment module including a stage 33, a rotating mechanism 34, an illumination unit 38, and a light receiving unit 39 is provided at the front of the batch exposure module 3, and the notch N is detected and the orientation of the wafer W is adjusted based on the detection by the orientation adjustment module, so that the wafer W is carried into the exposure module 3 in the same orientation every time. Then, the control unit 10 can detect the orientation of the rotation shaft of the motor constituting the rotating mechanism 34 that rotates the stage 33, and the stage is oriented to a predetermined direction when the wafer W is delivered. That is, the wafer W is delivered to the stage 33 so that the orientation of the wafer W is the same as the orientation of the stage 33 every time. According to this configuration, even if the stage 33 is slightly tilted due to the accuracy error of the structure of the batch exposure module 3, etc., the wafers W transported to the batch exposure module 3 are tilted in the same manner. Therefore, by setting the light amount for each unit 4 so that the influence of the tilt amount is eliminated, the CD uniformity in the plane of each wafer W can be further improved.

[0091] In addition, when the wafer W is transported to the batch exposure module 3 in a predetermined orientation by the orientation adjustment module as described above, the control unit 10 can detect the rotation amount of the motor of the above-mentioned rotating mechanism 34 after the wafer W is transported to the mounting table 33. With this configuration, the wafer W can be oriented to a predetermined direction even if the orientation of the wafer W is not detected by the illumination unit 38 and the light receiving unit 39 in the batch exposure module 3 each time the non-rotational batch exposure is performed. That is, the illumination unit 38 and the light receiving unit 39 for detecting the orientation of the wafer W are provided in the exposure module 3, but are not limited thereto. In addition, the orientation detection of the wafer W is not limited to the use of the illumination unit 38 and the light receiving unit 39. For example, a camera for photographing the surface of the wafer W may be provided in the batch exposure module 3, and the control unit 10 may obtain image data output by the camera to detect the notch N.

[0092] In addition, for a resist film formed with a non-chemically amplified resist on a wafer W, by being processed in the collective exposure module of each embodiment described above, the exposure amount of each part is made appropriate, and the resist pattern can be made uniform in each part within the surface of the wafer W. That is, each collective exposure module can also be applied to a wafer W coated with a non-chemically amplified resist. Furthermore, when the resist film or an organic film other than the resist film is hardened according to the exposure amount, the film is processed by the collective exposure module 3 described above, and by controlling the degree of curing of the film, the film can be etched with high uniformity within the surface of the wafer W during etching. In addition, when a film decomposed by exposure is formed on the wafer surface, the film thickness distribution within the surface of the wafer W can be adjusted. That is, the present invention not only uses the CD by adjusting the resist pattern. Therefore, the exposure device in the present invention is not limited to a device for exposing a resist, but can also be a light irradiation device for irradiating light to a substrate for processing.

[0093] In addition, when adjusting the CD of the resist pattern as described above, the exposure module 3 is not limited to being set at the above-mentioned position. For example, between the processing block D2 and the interface block D3, a conveying mechanism for handing over the wafer W, the exposure module 3, and a block having a handover module (referred to as an intermediate block) are provided. Then, the conveying mechanism of the intermediate block conveys the wafer W that has been exposed to the pattern of the handover modules TRS51 and TRS61 of the tower T2 from the interface block D3 to the exposure module, and then conveys it to the handover module of the intermediate block. It can be constructed as follows: the conveying arms F5 and F6 of the unit blocks E5 and E6 access the handover module, and convey the wafer W that has been exposed together to the unit blocks E5 and E6 for subsequent processing.

[0094] In addition, the exposure of the entire surface of the wafer W only requires that the entire area of ​​the surface of the wafer W where the semiconductor device is formed is exposed. Therefore, even if the outside of the formation area of ​​the semiconductor device is not exposed, the entire surface of the wafer W is also exposed when the formation area is exposed. In addition, the number of LEDs 47 arranged in the front-to-back direction and the number of LEDs 47 arranged in the left-to-right direction in the light source unit 40 are not limited to the numbers in the above example. In addition, a homogenizer composed of a lens array, a focusing lens or a prism is arranged below each LED 47 to make the distribution of the light amount in the front-to-back direction of the irradiation area 30 uniform. In addition, instead of moving the wafer W relative to the light source unit 40, the light source unit 40 is moved relative to the wafer W, so that the above-mentioned exposure can be performed simultaneously. In addition, the present invention is not limited to the above-mentioned embodiments, and the embodiments can be combined with each other or appropriately changed.

Claims

1. An exposure device, characterized in that: include: a mounting portion for mounting a substrate; A light emitting unit group composed of a plurality of light emitting units arranged left and right to form a strip-shaped irradiation area from one end to the other end of the surface of the substrate, wherein the light irradiation unit is composed of a plurality of light emitting units arranged front and back; a current adjustment unit for adjusting a current supplied to the light emitting unit group for each of the light irradiating units; a moving mechanism for causing the substrate placed on the placing portion to rotate relative to the irradiation region and to move relative to the irradiation region to expose the entire surface of the substrate; and A control unit, the control unit outputs a control signal to perform the following steps: The step of exposing the entire surface of the substrate by relatively moving the substrate in the front-rear direction relative to the irradiation area and rotating the substrate relative to the irradiation area.

2. The exposure device according to claim 1, characterized in that: The control unit outputs a control signal to execute the following steps: The first step is to rotate the substrate relative to the irradiation area formed with the first illumination distribution to expose the entire surface of the substrate; and In the second step, while the rotation of the substrate is stopped, the substrate is relatively moved in the front-rear direction with respect to the irradiation area formed with the second illumination distribution, so as to expose the entire surface of the substrate.

3. The exposure device according to claim 2, characterized in that: The first step is performed by forming a first illumination distribution in the irradiation area, The second step is performed by forming a second illuminance distribution different from the first illuminance distribution in the irradiation area.

4. The exposure device according to claim 1, characterized in that: The control unit outputs a control signal to execute the following steps: A first forward and backward movement step of relatively moving the carrier portion in the forward and backward direction with respect to the irradiation area to expose the entire surface of the substrate; Next, a step of rotating the substrate to change its orientation; and Next, a second forward and backward movement step is performed in which the mounting portion is relatively moved in the forward and backward direction with respect to the irradiation area to expose the entire surface of the substrate.

5. An exposure method, characterized in that: include: a step of placing a substrate on a placing portion; A step of forming a strip-shaped irradiation area from one end to the other end of the surface of the substrate by using a light emitting unit group composed of a plurality of light irradiating units arranged in a left-right manner, wherein the light irradiating unit is composed of a plurality of light irradiating units arranged in a front-to-back manner; a step of adjusting the current supplied to the light emitting section group for each of the light irradiating sections by using a current adjusting section; and an exposure step in which the substrate mounted on the mounting portion is rotated relative to the irradiation area and moved back and forth relative to the irradiation area by a moving mechanism to expose the entire surface of the substrate; In the exposure step, the entire surface of the substrate is exposed by moving the substrate relative to the irradiation area in the front-rear direction and rotating the substrate relative to the irradiation area.

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