Semiconductor measurement system and measurement method

Abstract

A semiconductor measurement system (1) includes a stage (22), a motion module, a measuring head (23), and several oscillating lifting modules (2). The stage (22) is positioned on the motion module and has a mounting surface. The motion module is connected to the stage (22) and interlocks with the stage (22) to control the movement of the wafer (3) to be measured. The oscillating lifting modules (2) are positioned higher than the motion module and include a drive assembly (10), a link rod (12), and a support pin (121), the ends of which are connected to the drive assembly (10) and the support pin (121), respectively, the link rod (12) is fixedly positioned perpendicular to the support pin (121), and the drive assembly (10) can interlock with the link rod (12) and further drive the oscillating of the support pin (121). The semiconductor measurement system (1) moves the support pins (121) in conjunction with the swinging motion to move the wafer (3) away from the stage (22) and raise it to a predetermined standby position, ensuring a safe distance to avoid the wafer (3), and then moves the wafer (3) to complete the measurement of the entire wafer. This reduces the overall space occupied by the measurement device, achieves a reduction in the volume of the measurement device, and also measures the necessary azimuth angle with respect to the measurement target point on the wafer (3) to be measured.

Description

Technical Field

[0001] This application relates to the field of semiconductor devices, and more particularly, to semiconductor measurement systems and measurement methods.

Background Art

[0002] Currently, the manufacturing of chips requires hundreds to thousands of process steps on a wafer. At the same time, it is necessary to perform measurements and monitoring on the production process to improve the chip yield. Separate from semiconductor process devices, semiconductor measurement devices also constitute an independent system. The silicon wafer is carried into the work stage of the measurement device via a load port, and then the silicon wafer is measured through a measurement probe, for example, film thickness measurement, critical dimension measurement, pattern overlay measurement, surface defect detection measurement, etc. can be realized.

[0003] In the prior art, in order to realize the execution of measurements on the entire wafer, it is necessary to ensure sufficient space for the wafer to move in the semiconductor measurement device. Generally, the strokes of the wafer moving along the X and Y directions in the horizontal plane are both larger than the diameter of the wafer. Therefore, the conventional measurement device is large in volume and occupies a large space in the semiconductor manufacturing factory. Also, in the entire production process, since the wafer needs to be transported multiple times between the process device and the measurement device, it takes time and affects the production efficiency of the chips. How to solve the above technical problems is something that those skilled in the art should consider.

Summary of the Invention

Problems to be Solved by the Invention

[0004] The semiconductor measurement system and measurement method provided by this application are for solving the problem of how to reduce the volume of the measurement device and realize the measurement of the required azimuth angles for all measurement points of the measurement target wafer.

Means for Solving the Problems

[0005] In a first aspect, an embodiment of the present application provides a semiconductor measurement system comprising an instrument housing surrounding a measurement chamber, a stage disposed within the measurement chamber, a motion module, several oscillating lifting modules, and a measurement head. The stage is disposed within the motion module and has a mounting surface, and is used to place a wafer to be measured during the measurement process. The motion module is connected to the stage and controls the movement of the wafer to be measured by linking the stage, and includes a first motion stage, a second motion stage, a third motion stage, and a rotation stage, wherein the first motion stage is movable along the X direction in a horizontal plane, the second motion stage is movable along the Y direction in a horizontal plane, the third motion stage is movable vertically, and the rotation stage is rotatable in a horizontal plane. The rocking lifting module is directly or indirectly connected to the equipment housing and positioned higher than the motion module, and includes a drive assembly, a link rod, and a support pin, the ends of which are connected to the drive assembly and the support pin, respectively, the link rod is fixedly positioned perpendicular to the support pin, and the drive assembly interlocks the link rod to cause the support pin to move up and down along the vertical direction and / or rock around the vertical direction, thereby controlling the support pin to move closer to or away from the wafer to be measured, enabling the transport and transfer of the wafer to be measured between the support pin and the stage. The measuring head performs region-specific optical measurements on the wafer to be measured placed on the stage and acquires the parameters to be measured.

[0006] Compared to conventional technology, the semiconductor measurement system of this embodiment, by arranging a swing-type lifting module, controls the drive assembly to lower and swing the support pins in conjunction with the drive assembly when transport and transfer of the wafer to be measured is necessary, thereby directing the wafer to be measured between the stage and the support pins. When transport and transfer of the wafer to be measured is not necessary, the drive assembly swings the support pins in conjunction with the drive assembly to move away from the stage and rise to a predetermined standby position, thereby ensuring a safe distance to avoid the wafer to be measured and completing the measurement of the entire wafer. As a result, the overall space occupied by the measurement device is reduced, and the volume of the measurement device is reduced. By working in conjunction with the motion module, it is possible to achieve motion in the X and Y directions, vertical lifting and lowering, and rotational motion in the horizontal plane of the wafer being measured. This allows for region-specific measurements on the wafer, reduces the maximum range of motion of the motion module in the horizontal plane, further reduces the spatial volume of the measurement device, and ensures that all measurement ports on the wafer being measured meet the measurement requirements for different azimuth angles, improving the signal-to-noise ratio of the measurement signal and obtaining more precise measurement results.

[0007] In one possible embodiment, the drive assembly includes a housing, a movable member, a guide groove, a contact member, and a drive source. The housing has a chamber extending along a first direction. The movable member is positioned within the chamber, with one end of the movable member connected to the link rod. The guide groove is formed in the movable member or the housing. The contact member is used to connect the housing and the movable member and has at least one end extending to the guide groove, and is movable relative to the guide groove to guide the movement of the movable member. The drive source is used to drive the movable member and, based on the relative movement of the contact member within the guide groove, drives the link rod, and further drives the support pin movable member to move up and down along the vertical direction and / or swing about the vertical direction.

[0008] In one possible embodiment, the guide groove includes a turning groove, the direction of extension of the turning groove is arranged at an angle with the first direction.

[0009] In one possible embodiment, the guide groove is opened on the outer circumference of the movable member or formed to penetrate the base of the movable member, one end of the contact member is fixedly positioned in the housing, and the other end of the contact member extends into the guide groove.

[0010] In one possible embodiment, the guide groove is formed to open into the inner wall of the housing or to penetrate the side wall of the housing, one end of the contact member is fixedly positioned on the movable member, and the other end of the contact member extends into the guide groove.

[0011] In one possible embodiment, the drive source includes a gas drive system or a liquid drive system, both of which include a sealing member, the sealing member being located within the chamber and fixedly connected to the movable member, the sealing member and the housing forming a pressure-variable chamber, and the pressure within the pressure-variable chamber is adjusted by changing the gas or liquid content within the pressure-variable chamber to drive the movement of the sealing member and the movable member.

[0012] The drive source includes an electric drive system, the electric drive system includes a motor, the motor is connected to the movable member and drives the movement of the movable member.

[0013] A recessed area is provided at the free end of the support pin, and this recessed area is used to support the wafer to be measured when transporting and transferring the wafer to be measured.

[0014] In one possible embodiment, the maximum motion stroke of the first motion stage is L1, and the maximum motion stroke of the second motion stage is L2, where L1 ∈ [D / 2, D / 2 + δ L ], L2∈[D,D+δ L], D is the diameter of the wafer to be measured, and 0 < δ L The limit is 20mm.

[0015] In one possible embodiment, the parameters to be measured include at least one of the following: film thickness on the surface of the wafer to be measured, pattern critical dimension, pattern overlay, and defect detection measurement.

[0016] In one possible embodiment, a connection port is provided on one side of the equipment housing, the connection port is in communication with the measurement chamber and is connectable to the wafer cassette interface of a semiconductor production device.

[0017] In a second embodiment, the present invention provides a measurement method for measuring a wafer to be measured using a semiconductor measurement system described in any one of embodiments 1 to 11. The measurement method includes a wafer loading step, a signal acquisition step, and a wafer unloading step, the wafer loading step including performing a first drive on the link rod by the drive assembly to position the support pins higher than the aforementioned mounting surface and facing the stage, transporting the wafer to be measured onto the support pins, controlling the stage to rise to a position where the aforementioned mounting surface contacts and supports the wafer to be measured, and detaching the wafer to be measured from the support pins, and performing a second drive on the link rod by the drive assembly to swing the support pins away from the stage and raise them to a predetermined standby position. The signal acquisition step includes collecting measurement signals from measurement points on the surface of the wafer to be measured placed on the stage based on the measurement head, and obtaining the measurement parameters. The wafer unloading step includes performing a third drive on the link rod by the drive assembly to position the support pins lower than the lower surface of the wafer to be measured and facing the stage, controlling the stage to descend until the support surface is separated from the wafer to be measured, so that the support pins support the wafer to be measured, and transporting the wafer to be measured out of the measurement chamber, and performing a fourth drive on the link rod by the drive assembly to raise the support pins to a predetermined standby position while swinging them away from the stage.

[0018] The signal acquisition step further includes acquiring opposing first semicircular measurement target region and second semicircular measurement target region by performing region division on the wafer to be measured, rotating the wafer to be measured by a motion module so that the incident light emitted by the measurement head has a predetermined measurement azimuth angle with respect to the measurement target region based on the characteristics of the measurement target points, moving each of the measurement target points in the first semicircular measurement target region to the irradiation spot position of the incident light by the first motion stage and / or second motion stage, collecting the measurement signal of each of the measurement target points, rotating the wafer to be measured by 180°, moving each of the measurement target points in the second semicircular measurement target region to the irradiation spot position of the incident light by the first motion stage and / or second motion stage, collecting the measurement signal of each of the measurement target points in the second semicircular measurement target region, and performing a measurement on the entire wafer to be measured.

[0019] To more clearly explain the technical solution of this embodiment, the drawings of the embodiment are briefly described below. It should be understood that the following drawings only show embodiments of the present application and should not be considered limiting in scope. Those skilled in the art can obtain other relevant drawings based on these drawings without any creative work. [Brief explanation of the drawing]

[0020] [Figure 1] Figure 1 is a schematic diagram of the semiconductor measurement system of this application. [Figure 2] Figure 2 is a schematic diagram showing how a rocking lifting module supports the wafer to be measured. [Figure 3] Figure 3 is a partial cross-sectional view of a swing-type lifting module. [Figure 4] Figure 4 is an exploded view of the rocking lifting module. [Figure 5] Figure 5 is a schematic diagram showing how a rocking lifting module and a robotic arm transfer the wafer to be measured. [Figure 6]FIG. 6 is a schematic process diagram of the load / unload process. [Figure 7] FIG. 7 is a schematic diagram of the rotational measurement for each measurement point and region on the surface of the wafer to be measured. [Figure 8] FIG. 8 is a schematic structural diagram of the diffraction grating at the measurement point.

Embodiments for Carrying out the Invention

[0021] Hereinafter, while referring to the drawings in the embodiments of the present application, the technical solution means in the embodiments of the present application will be clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present application, not all of the embodiments.

[0022] Some embodiments of this specification will be described in detail. The following embodiments and features of the embodiments can be combined with each other as long as they do not conflict.

[0023] Embodiment In the first embodiment, as shown in Figures 1 and 2, this embodiment provides a semiconductor measurement system 1, which includes an equipment housing 29 surrounding a measurement chamber, a stage 22 disposed within the measurement chamber, a motion module, several oscillating lifting modules 2, and a measurement head 23. Here, the stage 22 is disposed on the motion module and has a mounting surface, and is used to place the wafer 3 to be measured during the measurement process. The motion module is connected to the stage 22 and controls the movement of the wafer 3 to be measured by linking the stage 22, and includes a first motion stage 24, a second motion stage 25, a third motion stage 26, and a rotation stage 27, the first motion stage 24 being movable along the X direction in a horizontal plane, the second motion stage 25 being movable along the Y direction in a horizontal plane, the third motion stage 26 being able to move up and down along the vertical direction, and the rotation stage 27 being able to rotate in a horizontal plane. The oscillating lifting module 2 is directly or indirectly connected to the equipment housing 29 and positioned higher than the motion module, and includes a drive assembly 10, a link rod 12, and a support pin 121. Both ends of the link rod 12 are connected to the drive assembly 10 and the support pin 121, respectively, and the link rod 12 is fixedly positioned perpendicular to the support pin 121. The drive assembly 10 drives the control pin 121 to move up and down along the vertical direction and / or oscillate around the vertical direction by linking the link rod 12, thereby controlling the support pin 121 to move closer to or away from the wafer 3 to be measured, enabling transport and transfer of the wafer 3 to be measured between the support pin 121 and the stage 22. The measurement target parameter measurement head 23 performs region-specific optical measurements on the wafer 3 to be measured placed on the stage 22 and acquires the measurement target parameters.

[0024] In this embodiment, the semiconductor measurement system 1, by arranging a swing-type lifting module 2, controls the drive assembly 10 to lower and swing the support pins 121 in conjunction with the stage 22 and direct the wafer 3 to the stage 22 when transport and transfer of the wafer 3 to be measured is required, so that the wafer 3 to be measured is transferred between the stage 22 and the support pins 121. When transport and transfer of the wafer 3 to be measured is not required, the drive assembly 10 raises the support pins 121 to a predetermined standby position while moving it away from the stage 22, thereby ensuring a safe distance to avoid the wafer 3 to be measured and completing the measurement of the entire wafer. This achieves the effect of reducing the overall space occupied by the measurement device and reducing the volume of the measurement device. By working in conjunction with the motion module, the wafer 3 to be measured can achieve horizontal X and Y direction motion, vertical vertical lifting and lowering motion, and rotational motion, enabling region-specific measurements on the wafer 3. Furthermore, it reduces the maximum horizontal motion range of the motion module, reduces the spatial volume of the measurement device, and ensures that the measurement target points 30 on the wafer 3 meet the optimal azimuth angle measurement requirements, resulting in the acquisition of a measurement signal with a high signal-to-noise ratio and, consequently, more precise measurement results.

[0025] As shown in Figures 2 to 4, in this embodiment, the drive assembly 10 in the rocking lifting module 2 includes a housing 11, a movable member 14, a guide groove 15, a contact member 13, and a drive source. The housing 11 has a chamber 111 extending along a first direction 16. The movable member 14 is located within the chamber 111, and one end of the movable member 14 is connected to the link rod 12. The guide groove 15 is opened in the movable member 14 or in the inner wall of the housing 11. The contact member 13 is used to connect the housing 11 and the movable member 14 and extends at least one end to the guide groove 15, and the contact member 13 can move relative to the guide groove 15 to guide the movement of the movable member 14. A drive source (not shown) is used to drive the movable member 14 and to interlock the link rod 12 based on the relative movement of the contact member 13 in the guide groove 15, thereby driving the control pin 121 to move up and down along the vertical direction and / or rock about the vertical direction.

[0026] For example, the housing 11 may be a cylindrical body having a hollow chamber and having openings on both its upper and lower surfaces. The movable member 14 may also be a cylindrical body and is housed within the hollow chamber of the housing 11. The lower end of the movable member 14 is connected to a link rod 12, which extends from an opening on the lower surface of the housing 11. A guide groove 15 is provided on the outer circumference of the movable member 14, and the guide groove 15 may penetrate the entire base of the movable member 14. A through-hole 114 is provided in the housing 11, which communicates with the chamber 111, and one end of the contact member 13 is fixedly positioned in the through-hole 114, with the other end of the contact member 13 extending into the guide groove 15, so that the contact member 13 can move relative to the guide groove 15, that is, the contact member 13 and the guide groove 15 cooperate to guide the movement of the movable member 14. The upper end of the movable member 14 is connected to a drive source. The drive source is used to drive the movable member 14 and, based on the relative movement of the contact member 13 within the guide groove 15, interlocks the link rod 12 and drives the control pin 121 to move up and down along the vertical direction and / or swing around the vertical direction, thereby controlling the support pin 121 to move closer to or away from the wafer 3 to be measured, and thereby realizing the transport and transfer of the wafer 3 to be measured between the support pin 121 and the stage 22. Preferably, in this embodiment, the contact member 13 is a plug. Alternatively, the guide groove 15 may be located on the inner wall of the housing 11 or penetrate the side wall of the housing 11, with one end of the contact member 13 fixed to the side wall of the movable member 14 and the other end of the contact member 13 extending into the guide groove 15, thereby similarly moving the contact member 13 relative to the guide groove 15 to guide the movement of the movable member 14, and further driving the pin 121 to move up and down along the vertical direction and / or swing around the vertical direction. This embodiment is not limited to this.

[0027] Furthermore, the guide groove 15 includes a turning groove 124, the extension direction of the turning groove 124 is positioned at an angle with the first direction 16. Taking the example that the guide groove 15 is opened in the movable member 14, as shown in Figure 4, in a possible embodiment, the guide groove 15 further includes a tip section 125 and a terminal section 126. The turning groove 124 is positioned at an angle with the extension direction of the chamber 111 and is located between the tip section 125 and the terminal section 126, and the tip section 125, the turning groove 124 and the terminal section 126 are sequentially connected.

[0028] In this embodiment, the first direction 16 is the vertical direction, the tip section 125 and the end section 126 extend along the vertical direction, and the extension direction of the turning groove 124 forms an acute angle with the vertical direction. When the contact member 13 moves within the turning groove 124, the direction of motion of the movable member 14 forms an angle with the vertical direction, meaning that the movable member 14 simultaneously has a first motion component in the first direction 16 and a second motion component that swings about the vertical direction in the horizontal plane. At this time, the movable member 14 interlocks with the support pin 121 to simultaneously generate movement along the vertical direction and swing about the vertical direction. When the contact member 13 moves through the tip section 125 and the end section 126, the relative movement of the contact member 13 within the guide groove 15 is controlled by interlocking with the support pin 121 to move along the vertical direction, and further controlling the support pin 121 to move closer to or away from the wafer 3 to be measured.

[0029] In other embodiments, the extension shape of the guide groove 15 may vary. For example, the turning groove 124 may be perpendicular to the first direction 16 and connected to the tip section 125 and the end section 126, respectively. In this case, the extension direction of the turning groove 124 must form a non-orthogonal angle with the extension of the support pin 121. When the contact member 13 moves within the turning groove 124, the movable member 14 moves in conjunction with the support pin 121, causing it to swing around the vertical direction. When the contact member 13 moves within the tip section 125 and the end section 126, the method of movement for linking the support pin 121 is the same as in the above embodiment. Alternatively, the tip section 125, the turning groove 124, and the end section 126 may lie on a straight line, forming an inclined guide groove 15. Based on such an arrangement, when the contact member 13 moves within the guide groove 15, the movable member 14 moves along the vertical direction and swings around the vertical direction, causing the support pin 121 to move in conjunction. This embodiment is not limited thereto. In possible embodiments, at least one guide groove 15 is provided, the contact member 13 and the movable member 14 are separated and in contact, the contact member 13 can correspond to one guide groove 15, and the movable member 14 moves according to the shape of the guide groove 15.

[0030] In this embodiment, multiple guide grooves 15 are provided at intervals on the circumferential surface of the movable member 14, and the extension directions of each guide groove 15 may be the same or different. One contact member 13 is provided, and when it is necessary to change the movement method of the movable member 14, the contact member 13 is moved away from the guide grooves 15, then the movable member 14 is rotated to align the required guide groove 15 with the contact member 13, and then the contact member 13 is moved to the required guide groove 15 and contacts the groove side wall 151.

[0031] In other embodiments, multiple contact members 13 are provided, and each contact member 13 corresponds one-to-one with a guide groove 15. By moving one of the contact members 13 into the corresponding guide groove 15 and moving the other contact members 13 away from the guide groove 15, the movement mode of the movable member 14 can be flexibly adjusted and changed. This embodiment is not limited to this.

[0032] In this embodiment, the drive source includes at least one of a gas drive system, a fluid drive system, or an electric drive system. As shown in Figures 2 and 3, the drive source is connected to the movable member 14 via the upper opening 113 of the housing 11 and drives the movement of the movable member 14.

[0033] In one possible embodiment, the drive source is a gas drive system or a fluid drive system, which includes a seal member 17, which is located in a chamber 111 and fixedly connected to a movable member 14, and the seal member 17 and the housing 11 form a pressure-variable chamber, and the gas drive system or fluid drive system changes the gas or fluid content in the pressure-variable chamber and adjusts the pressure in the pressure-variable chamber to drive the movement of the seal member 17 and the movable member 14. Here, the trajectory of the movement of the movable member 14 is controlled by the cooperative movement of the contact member 13 and the guide groove 15.

[0034] In another possible embodiment, the drive source is an electric drive system, which includes a motor that is powered to the movable member 14 and synchronizes the movement of the movable member 14 by a screw.

[0035] In one possible embodiment, a recessed region 1211 is provided at the free end of the support pin 121, and the recessed region 1211 is used to hold the wafer 3 to be measured when transporting and transferring the wafer 3 to be measured. The shape of the recessed region 1211 is formed to conform to the wafer 3 to be measured and can be installed on an arched surface, and the support pin 121 cooperates with the circumferential surface of the wafer 3 to improve the stability of supporting the wafer 3.

[0036] In this embodiment, multiple oscillating lifting modules 2 are provided, and there may be three, four, or more of them. The multiple oscillating lifting modules 2 are distributed along the circumferential direction of the wafer 3 to be measured and together hold the wafer 3 to be measured.

[0037] As shown in Figure 6, Figures 6(e) and 6(a) show the wafer loading process of the wafer 3 to be measured along the direction of arrow A, and Figures 6(a) and 6(e) show the wafer unloading process of the wafer 3 to be measured along the direction of arrow B. Here, in the wafer loading stage in which measurement is performed, the support pins 121 are driven to be positioned higher than the mounting surface of the stage 22 and to face the stage 22. Then the wafer 3 to be measured is transported to the support pins 121, and the stage 22 is controlled to rise until the mounting surface of the stage 22 contacts and supports the wafer 3 to be measured, while the wafer 3 to be measured is released from the support pins 121. Subsequently, the swing of the support pins 121 is driven to move away from the stage and rise to a predetermined standby position. During the wafer unloading phase in which measurement is performed, the support pins 121 are driven to be lower than the lower surface of the wafer 3 to be measured and facing the stage 22. The stage 22 is controlled to lower until its mounting surface is separated from the wafer 3 so that the support pins 121 support the wafer 3 to be measured. Subsequently, the wafer 3 to be measured is transported out of the measurement chamber, and the swing of the support pins 121 is driven to raise it to a predetermined standby position away from the stage 22. By controlling the control support pins 121 to move closer to or away from the wafer 3 to be measured, it is possible to transport and transfer the wafer 3 to be measured between the support pins 121 and the stage 22.

[0038] Furthermore, each oscillating lifting module 2 can be provided with at least one support pin 121. Exemplarily, each oscillating lifting module 2 can be provided with two support pins 121, which are arranged in parallel in upper and lower layers and fixed to the link rod 12. The two support pins 121 in the upper and lower layers of each oscillating lifting module 2 are arranged in a one-to-one correspondence, making it easier for the support pins 121 in the same layer to hold the same wafer 3 to be measured, while the support pins 121 in different layers are used to hold the wafer 3 for which the measurement signal acquisition process has been performed and the wafer 3 for which signal acquisition is to be performed, respectively, during the operation period of the measurement device. This enables the transfer and handover of the wafer 3 between different nodes in the measurement process, improving the operational efficiency of the measurement system.

[0039] In this embodiment, the maximum motion stroke of the first motion stage 24 is L1, and the maximum motion stroke of the second motion stage 25 is L2, where L1∈[D / 2,D / 2+δ L ], L2∈[D,D+δ L ], D is the diameter of the wafer 3 being measured, and 0 < δ L≤20mm. As shown in Figure 7, multiple measurement points 30 are provided on the surface of the wafer 3 to be measured, and the dashed frame indicates the maximum movement stroke of the first movement stage 24 and the second movement stage 25, i.e., the movable range of the center of the wafer 3 to be measured. In the measurement process, the wafer 3 to be measured is divided into two semicircular measurement areas, and by controlling the movement stroke of the first movement stage 24 and the second movement stage 25, different measurement points 30 on the first semicircular measurement area are positioned on the irradiation spot 230 of incident light emitted by the measurement head 23, and the measurement signals of the corresponding measurement points 30 are collected. Next, the wafer 3 to be measured is rotated 180° by the rotation stage 27, and the measurement signals of different measurement points 30 on the second semicircular measurement area are collected. In this way, the measurement signals of all measurement points 30 on the entire surface of the wafer 3 to be measured are obtained, and the corresponding measurement parameters can be calculated. Simultaneously, the rotating stage 27 rotates the wafer 3 to be measured, allowing each measurement point 30 to acquire the required measurement azimuth angle, thereby satisfying the parameter requirements of the measurement system and improving the signal-to-noise ratio of the measurement signal, thereby improving the accuracy of the measurement results. In other words, this embodiment provides a semiconductor measurement system 1, and by arranging the oscillating lifting module 2 and the motion module in cooperation, it not only reduces the range of motion of the motion module and the overall spatial size of the system, but also fulfills the need to arrange different azimuth angles in the measurement process of measurement points 30 on different wafers 3, and guarantees the accuracy of the measurement results by acquiring a measurement signal with a high signal-to-noise ratio. As shown in Figure 1, the first motion stage 24, the second motion stage 25, the third motion stage 26 and the rotating stage 27 are stacked in order in the vertical direction, but this embodiment is not limited to this, and the order and position of their stacking can be changed in actual applications.

[0040] Exemplary, the parameters to be measured include at least one of the following: film thickness on the surface of the wafer 3 to be measured, pattern critical dimension, pattern overlay, and defect detection measurement.

[0041] In possible embodiments, the semiconductor measurement system 1 further includes a wafer transport module, which includes a robotic arm 28, as shown in Figure 5, which includes at least one transport arm used to pick up the wafer 3 to be measured during the wafer loading and wafer unloading phases and place it on the support pins 121. Preferably, a first transport arm 281 and a second transport arm 282 can be arranged to load and unload two wafers simultaneously and improve the operational efficiency of the measurement system.

[0042] In this embodiment, a connection port is located on one side of the equipment housing 29 of the semiconductor measurement system 1. The connection port communicates with the measurement chamber and can be connected to the wafer cassette interface of a semiconductor production device. Conventional semiconductor devices generally have a wafer cassette interface, which is connected to a load port. The wafer to be measured 3 is then grasped from a hoop (Front-opening unified pod, Foup) placed in the load port to load and unload the wafer to be measured 3. By providing a connection port on the side of the equipment housing 29 of the semiconductor measurement system 1 in this embodiment, the measurement system can be directly integrated into the end of a conventional process device. This not only avoids increasing the modification costs of the conventional process device, but also allows for the sharing of wafer transport modules compatible with conventional process devices. This significantly reduces the material costs of the measurement device, saves transport time which is performed multiple times alternately during the processing and measurement of the wafer to be measured 3, and greatly improves the production efficiency of wafer manufacturing.

[0043] In this embodiment, the measuring head 23 is fixed to the equipment housing 29 via a gantry (not shown). As shown in Figure 1, the measuring head 23 includes a light source 236, a polarizer 231, a first rotational compensator 232, a second rotational compensator 234, an analyzer 233, and a spectrometer 235. As shown in Figure 7, incident light supplied from the light source 236 passes sequentially through the polarizer 231 and the first rotational compensator 232 and enters the surface of the wafer 3 to be measured to form an illumination spot 230. A motion module positions the measurement target point 30 on the surface of the wafer 3 within the illumination spot 230. After the incident light is reflected by the measurement target point 30, it forms detection light. The detection light passes sequentially through the second rotational compensator 234 and the analyzer 233 before entering the spectrometer 235, where the spectrometer 235 collects the measurement signal of the measurement target point 30 and measures the wafer 3.

[0044] On the other hand, embodiments of this application further provide a measurement method for measuring a wafer 3 to be measured using a semiconductor measurement system 1, which includes a wafer loading stage, a signal acquisition stage, and a wafer unloading stage. Here, the wafer loading stage includes the following: A first drive is performed on the link rod 12 by the drive assembly 10 to position the support pin 121 higher than the mounting surface and facing the stage 22, transporting the wafer 3 to be measured to the support pin 121, controlling the stage 22 to rise to a position where the mounting surface contacts and supports the wafer 3 to be measured, and detaching the wafer 3 to be measured from the support pin 121, and a second drive is performed on the link rod 12 by the drive assembly 10 to swing the support pin 121 away from the stage 22 and raise it to a predetermined standby position. The signal acquisition stage includes the following: Based on the measurement head 23, measurement signals of measurement points 30 on the surface of the wafer 3 to be measured placed on the stage 22 are collected, and measurement parameters are obtained. The wafer unloading stage includes the following: The drive assembly 10 performs a third drive on the link rod 12, lowering the support pin 121 below the lower surface of the wafer 3 to be measured and pointing it toward the stage 22. The control stage 22 is then controlled to lower until the support pin 121 supports the wafer 3 to be measured and the mounting surface detaches from the wafer 3, thereby transporting the wafer 3 to the outside of the measurement chamber. The drive assembly 10 then performs a fourth drive on the link rod 12, causing the support pin 121 to swing away from the stage 22 and rise to a predetermined standby position.

[0045] The measurement method in this embodiment controls the cooperative operation between the oscillating lifting module 2 and the motion module to enable measurement within a narrow range of stroke of the entire wafer 3 to be measured. It also rotates the wafer 3 to be measured to an appropriate measurement position via the stage 22, and ensures that the incident light emitted from the measurement head 23 has a predetermined optimal measurement azimuth angle with respect to the measurement point 30, thereby acquiring a measurement signal with a high signal-to-noise ratio, and thus achieving high-precision measurement in a small volume space.

[0046] As shown in Figure 7, in this embodiment, the signal acquisition step further includes the following: The wafer to be measured 3 is divided into regions by its diameter CD, and opposing first semicircular measurement target region 31 and second semicircular measurement target region 32 are acquired. Based on the characteristics of the measurement target points 30, the wafer to be measured 3 is rotated by the motion module so that the incident light emitted by the measurement head 23 has a predetermined measurement azimuth angle with respect to the measurement target points 30. The first motion stage 24 and / or the second motion stage 25 move each measurement target point 30 in the first semicircular measurement target region 32 to the incident light irradiation spot 230, and the measurement signal of each measurement target point 30 is collected. The wafer to be measured 3 is rotated 180°, and the first motion stage 24 and / or the second motion stage 25 move each measurement target point 30 in the second semicircular measurement target region 32 to the incident light irradiation spot 230, the measurement signal of each measurement target point 30 is collected, and the measurement is performed on the entire wafer to be measured 3. In another possible embodiment, the motion module can be controlled to move the wafer 3 to be measured in a continuous or stepwise manner, thereby enabling full-sheet scan measurement of the wafer 3; however, the present invention is not limited thereto.

[0047] Exemplary, the characteristics of the measurement target point 30 include the structural pattern features of the measurement target point 30. Taking OCD measurement as an example, as shown in Figure 8, the measurement target point 30 includes a diffraction grating 301 structure, the diffraction grating 301 has periodicity along the X direction, arrows R1 and R2 represent the incident light and detected light, respectively, and the angle Φ between the incident plane 302 and the X direction is the azimuth angle of the incident light R1 with respect to the measurement target point 30. The magnitude of the azimuth angle is an important system parameter that affects the OCD measurement sensitivity, and different forms of diffraction grating structures correspond to different optimal azimuth angles.

[0048] The embodiments described above are merely illustrative and not limiting to the technical solution of this application. Although this application has been described in detail based on the preferred embodiments described above, those skilled in the art should understand that any modification or equivalent substitution of the technical solution of this application will not deviate from the spirit and scope of the technical solution of this application.

[0049] Explanation of the symbols 1...Semiconductor measurement system, 10...Drive assembly, 11...Housing, 111...Chamber, 113...Top opening, 114...Through hole, 12...Link rod, 121...Support pin, 1211...Recessed area, 124...Bending groove, 125...Tip section, 126...End section, 13...Contact member, 14...Movable member, 15...Guide groove, 151...Groove side wall, 16...First direction, 17...Sealing member, 2...Oscillating lifting module, 22...Stage, 23...Measurement head, 230...Irradiation spot, 231 ...polarizer, 232...first rotational compensator, 233...analyzer, 234...second rotational compensator, 235...spectrometer, 236...light source, 24...first motion stage, 25...second motion stage, 26...third motion stage, 27...rotation stage, 28...robot arm, 281...first transport arm, 282...second transport arm, 29...equipment housing, 3...wafer to be measured, 30...point to be measured, 301...diffraction grating, 302...incident surface, 31...first semicircular measurement area, 32...second semicircular measurement area.

Claims

1. A semiconductor measurement system comprising an instrument housing surrounding a measurement chamber, a stage, a motion module, several rocking lifting modules, and a measurement head, wherein The aforementioned stage is arranged in the motion module and has a mounting surface, and is used to mount the wafer to be measured during the measurement process. The motion module is connected to the stage and controls the movement of the wafer to be measured by linking the stage, and the motion module includes a first motion stage, a second motion stage, a third motion stage and a rotation stage, wherein the first motion stage is movable along the X direction in the horizontal plane, the second motion stage is movable along the Y direction in the horizontal plane, the third motion stage is movable up and down along the vertical direction, and the rotation stage is movable rotationally in the horizontal plane. The rocking lifting module is directly or indirectly connected to the equipment housing and positioned higher than the motion module, and includes a drive assembly, a link rod, and a support pin, the ends of which are connected to the drive assembly and the support pin, respectively, the link rod is fixedly positioned perpendicular to the support pin, and the drive assembly controls the link rod to move the support pin up and down along the vertical direction and / or rock around the vertical direction, thereby enabling the transport and transfer of the wafer to be measured between the support pin and the stage, by controlling the support pin to move closer to or away from the wafer to be measured. The semiconductor measurement system is characterized in that the measurement head performs region-specific optical measurements on the wafer to be measured, which is placed on the stage, and acquires the parameters to be measured.

2. The aforementioned drive assembly is A housing having a chamber extending along a first direction, A movable member is disposed within the chamber and one end of which is connected to the link rod, A guide groove is provided in the movable member or the housing, A contact member used to connect the housing and the movable member, with at least one end extending to the guide groove, wherein the contact member is relatively movable along the guide groove to guide the movement of the movable member, A drive source used to drive the movable member, which interlocks the link rod based on the relative movement of the contact member within the guide groove, and drives the support pin movable member to move up and down along the vertical direction and / or swing around the vertical direction, A semiconductor measurement system according to claim 1, characterized by including the following:

3. The semiconductor measurement system according to claim 2, characterized in that the guide groove includes a deflection groove, and the direction of extension of the deflection groove is arranged to form an angle with the first direction.

4. The semiconductor measurement system according to claim 2, characterized in that the guide groove is opened on the outer circumference of the movable member or formed so as to penetrate the base of the movable member, one end of the contact member is fixedly positioned in the housing, and the other end of the contact member extends into the guide groove.

5. The semiconductor measurement system according to claim 2, characterized in that the guide groove is opened in the inner wall of the housing or formed to penetrate the side wall of the housing, one end of the contact member is fixedly positioned on the movable member, and the other end of the contact member extends into the guide groove.

6. The semiconductor measuring system according to claim 2, wherein the drive source includes a gas drive system or a liquid drive system, and the gas drive system or the liquid drive system both include a seal member, the seal member is disposed in the chamber and fixedly connected to the movable member, the seal member and the housing form a variable pressure chamber, and the pressure in the variable pressure chamber is adjusted by changing the gas or liquid content in the variable pressure chamber to drive the movement of the seal member and the movable member.

7. The semiconductor measurement system according to claim 2, wherein the drive source includes an electric drive system, the electric drive system includes a motor, the motor is connected to the movable member and drives the movement of the movable member.

8. The semiconductor measurement system according to claim 1, characterized in that a recessed area is provided at the free end of the support pin, and the recessed area is used to support the wafer to be measured when transporting and transferring the wafer to be measured.

9. The maximum motion stroke of the first motion stage is L １ The maximum motion stroke of the second motion stage is L ２ And, L １ ∈[D / 2,D / 2+δ Ｌ ]、L ２ ∈[D,D+δ Ｌ ]、 D is the diameter of the wafer being measured, and 0 < δ Ｌ The semiconductor measurement system according to claim 1, characterized in that the size is ≤20 mm.

10. The semiconductor measurement system according to claim 1, characterized in that the measurement target parameter includes at least one of the following: film thickness of the wafer surface to be measured, pattern critical dimension, pattern overlay, and defect detection measurement.

11. The semiconductor measurement system according to any one of claims 1 to 10, characterized in that a connection port is provided on one side of the equipment housing, the connection port communicates with the measurement chamber and is connectable to the wafer cassette interface of a semiconductor production device.

12. A measurement method for measuring a wafer to be measured using a semiconductor measurement system according to any one of claims 1 to 11, The measurement method includes a wafer loading step, a signal acquisition step, and a wafer unloading step. The wafer loading step includes: performing a first drive on the link rod by the drive assembly to position the support pin higher than the aforementioned mounting surface and facing the stage, transporting the wafer to be measured to the support pin, controlling the stage to rise to a position where the aforementioned mounting surface contacts and supports the wafer to be measured, and detaching the wafer to be measured from the support pin; performing a second drive on the link rod by the drive assembly to swing the support pin away from the stage and raise it to a predetermined standby position; The signal acquisition step includes, based on the measurement head, acquiring measurement signals from measurement points on the surface of the wafer to be measured placed on the stage, and obtaining the measurement target parameters. The wafer unloading step is characterized by the following steps: the drive assembly performs a third drive on the link rod to position the support pins lower than the lower surface of the wafer to be measured and facing the stage, controlling the stage to descend until the support surface is separated from the wafer to be measured, so that the support pins support the wafer to be measured, the wafer to be measured is removed from the measurement chamber, and the drive assembly performs a fourth drive on the link rod to raise the support pins to a predetermined standby position while swinging them away from the stage.

13. The aforementioned signal acquisition step is By performing region division on the wafer to be measured, the opposing first semicircular measurement target region and the second semicircular measurement target region are obtained. Based on the characteristics of the measurement target point, the motion module rotates the measurement target wafer so that the incident light emitted by the measurement head has a predetermined measurement azimuth angle with respect to the measurement target point. The first motion stage and / or the second motion stage move each of the measurement target points within the first semicircular measurement target area to the irradiation spot position of the incident light, and collect the measurement signal of each of the measurement target points. The measurement method according to claim 12, further comprising rotating the wafer to be measured by 180°, moving each of the points to be measured within the second semicircular measurement target area to the irradiation spot position of the incident light using the first motion stage and / or the second motion stage, collecting the measurement signal of each of the points to be measured within the second semicircular measurement target area, and performing a measurement on the entire wafer to be measured.

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