Wafer position alignment device

Abstract

The present invention relates to a wafer position alignment device for aligning the centers of wafers seated on wafer holders. The wafer position alignment device comprises: a determination module for determining the seated state of wafers seated on a first wafer holder to a third wafer holder; a push module for pushing the wafers, according to the state determined by the determination module, to keep the wafers in a normal seated state; a driving module for driving the push module; and a control module for controlling the operation of the driving module, and thus can easily carry out position alignment of wafers.

Description

Wafer position alignment device

[0001] The present invention relates to a wafer position alignment device applied to a wafer defect inspection system, and more specifically, to a wafer position alignment device that aligns the center of a wafer placed on a wafer support.

[0002] Generally, semiconductor devices are manufactured by performing various unit processes on a silicon wafer used as a semiconductor wafer to form an electrical circuit containing electrical components on the silicon wafer.

[0003] Meanwhile, as the integration density of semiconductor devices increases, the yield and reliability of these devices are significantly affected by the quality of the wafers on which they are fabricated. Wafer quality is determined by the number of defects generated throughout the entire process of wafering, which involves fabricating the wafer during crystal growth.

[0004] These wafer defects can be classified into defects caused by external contaminants and crystal defects occurring during ingot growth. Among these, external contaminants such as dust are easily removed by etching or cleaning processes; however, crystal defects such as COP (Crystal Originated Particles), FPD (Flow Pattern Defect), OiSF (Oxygen-induced Stacking Fault), BMD (Bulk Micro Defect), and LDP (Large Dislocation Pit) are not removed by cleaning processes and remain, affecting the yield and quality of semiconductor devices; therefore, their occurrence must be suppressed during the wafer fabrication process. Accordingly, verifying and inspecting the accurate distribution and density of these defects prior to implementing semiconductor devices on the wafer is crucial for yield management.

[0005] In other words, wafers used in the manufacture of semiconductor devices are prepared by thinly slicing silicon ingots, and impurities can be introduced due to the high growth temperatures during ingot growth. During this ingot growth, voids or crystal defects caused by rotational speed or oxygen levels can lead to the formation of air pockets, and these defects are transferred directly to the sliced ​​wafers. Wafers with defects such as air pockets are mostly discarded. Furthermore, wafers are subjected to thermal or physical stress while undergoing multiple processes. At this time, if even minor defects such as cracks are present on the wafer, new cracks may develop or semiconductor device products may fail due to thermal or physical stress during the process, leading to a decrease in yield.

[0006] A wafer defect inspection system for inspecting defects on the surface or inside a wafer as described above is known. In order to obtain accurate defect inspection results in such a wafer defect inspection system, the wafer mounted on a plurality of supports must be centered.

[0007] For example, Patent Document 1 (U.S. Published Patent Application No. 2025-0149366, published May 8, 2025) discloses a wafer holding device comprising a base, a holder plate, a plurality of pushing pins, a linear actuator, and a positioning member, wherein the holder plate is disposed on the base, and an adsorption structure for adsorbing and fixing a wafer is provided on the upper surface of the holder plate, the plurality of pushing pins are disposed on the upper surface in a protruding manner, and each pushing pin is disposed on the holder plate with respect to a predetermined reference center on the holder plate, the linear actuator is disposed on the base, and the operating direction of the linear actuator is parallel to the upper surface, and the positioning member is driven by the linear actuator to move in the operating direction to contact and push against the positioning structure of the wafer.

[0008] In addition, Patent Document 2 (Republic of Korea Registered Patent Publication No. 10-2012339, published on August 20, 2019) discloses a wafer centering device for a measuring instrument comprising a push module formed to press a wafer to a center position and a driving module that operates the push module in forward and backward directions relative to the wafer, wherein the driving module comprises a cylinder having an internal space having a first area and a second area, a piston disposed in the internal space to distinguish the first area and the second area, a moving unit having a rod connecting the piston to the push module, and an air supply unit having a forward air input unit that inputs a first air to the first area to move the piston and the push module in the forward direction and a backward air input unit that inputs a second air to the second area to move the piston and the push module in the backward direction.

[0009] Meanwhile, Patent Document 3 (Japanese Published Patent Application No. 2006-222262, published on August 24, 2006) discloses a mask positioning device having a first jig having a wafer mounting surface on which a wafer is mounted and an outer wall formed along the outer periphery of the wafer mounting surface, a frame having an inner wall on which a mask is fixed, and a second jig having a pair of wafer position correction mechanisms arranged oppositely on the bottom surface of the frame with the center of the frame in between, wherein the side of the wafer is pressed toward the center of the wafer mounting surface by the wafer position correction mechanism that contacts the side of the wafer by contacting the frame to the outer wall from the upper surface side of the wafer while the wafer is mounted on the wafer mounting surface.

[0010] Patent document 1, as described above, discloses a technology in which a positioning member is driven by a linear actuator to contact and push against a positioning structure of a wafer, and patent document 2 discloses a technology in which a drive module that presses the wafer moves toward the wafer to move the wafer to a center position, and patent document 3 discloses a technology in which a wafer positioning member contacts a roller of a wafer positioning mechanism opposite to the wafer positioning mechanism and is positioned on a predetermined part of the wafer mounting surface, but there is no technology in which the wafer is prevented from deviating in a certain direction during the centering process by a wafer support and an equal arrangement configuration.

[0011] In other words, the prior art described above did not disclose a technology for solving the problem of reduced precision when measuring wafer defects, such as holding or review images, caused by the wafer rotating slightly due to the misalignment of the wafer supporter and wafer pusher during the wafer pushing operation to maintain the wafer center.

[0012] The objective of the present invention is to solve the problems described above by providing a wafer position alignment device applicable to a wafer defect inspection system that can maintain the center of the wafer during wafer defect inspection using a wafer pusher.

[0013] Another objective of the present invention is to provide a wafer position alignment device that can improve wafer defect inspection accuracy by centering the wafer without rotating it when maintaining the wafer center.

[0014] Another objective of the present invention is to provide a wafer position alignment device that can reduce the time required for wafer defect inspection by reducing the time required for wafer centering.

[0015] To achieve the above objective, the wafer position alignment device according to the present invention is a device for aligning the position of a wafer placed on a first wafer support, a second wafer support, and a third wafer support, and is characterized by comprising: a judgment module for determining the seating state of a wafer placed on the first to third wafer supports; a push module for pushing the wafer according to the judgment state of the judgment module to maintain the wafer in a normal seating state; a driving module for driving the push module; and a control module for controlling the operation of the driving module.

[0016] In addition, in the wafer position alignment device according to the present invention, the push module is characterized by being arranged in an isogonal state with respect to the second wafer support and the third wafer support.

[0017] In addition, in the wafer position alignment device according to the present invention, the push module is characterized by being provided at a position opposite in a straight line to a display cover portion formed corresponding to a notch portion or a flat zone portion to cover a notch portion or a flat zone portion provided on the wafer.

[0018] In addition, in the wafer position alignment device according to the present invention, the first wafer support is characterized by being provided adjacent to the push module.

[0019] In addition, in the wafer position alignment device according to the present invention, the first wafer support includes a seating portion on which the wafer is placed, and the seating portion is characterized by being provided with a curved surface so that the wafer can move.

[0020] In addition, in the wafer position alignment device according to the present invention, the push module is characterized by pushing a wafer mounted on the first wafer support, the second wafer support, and the third wafer support in the direction of the second wafer support and the third wafer support.

[0021] In addition, in the wafer position alignment device according to the present invention, the push module is characterized by comprising a pusher for pushing the wafer, a pusher bracket coupled to the pusher, a moving member for moving the pusher bracket back and forth, and a holding member provided on a subtable for holding the moving member.

[0022] In addition, in the wafer position alignment device according to the present invention, the pusher is characterized by being made of PEEK (Polyether Ether Ketone).

[0023] In addition, in the wafer position alignment device according to the present invention, the moving member is characterized by including a pneumatic cylinder or a hydraulic cylinder.

[0024] In addition, in the wafer position alignment device according to the present invention, the moving member is characterized by including a ball screw member.

[0025] In addition, the wafer position alignment device according to the present invention further includes a sensing module that detects the seating state of the wafer, and the control module controls the operation of the driving module according to the detection result of the sensing module.

[0026] As described above, according to the wafer position alignment device applied to the wafer defect inspection system according to the present invention, the push module is arranged in a structure in which it is positioned isogonally with respect to the second wafer support and the third wafer support, and by pushing the center of the wafer seated on the wafer stage with the push module, the effect of easily realizing the position alignment of the wafer is obtained.

[0027] In addition, according to the wafer position alignment device of the present invention, the position of the wafer can be accurately aligned, thereby achieving the effect of improving inspection accuracy and reliability during wafer defect inspection.

[0028] In addition, according to the wafer position alignment device of the present invention, the effect of easily realizing the position alignment of the wafer and enabling high-speed wafer defect inspection is also obtained.

[0029] FIG. 1 is a configuration diagram of a wafer defect inspection system to which a wafer position alignment device according to the present invention is applied.

[0030] FIG. 2 is a front perspective view of a wafer defect measurement module equipped with a wafer position alignment device according to the present invention.

[0031] FIG. 3 is a rear perspective view of a wafer defect measurement module equipped with a wafer position alignment device according to the present invention.

[0032] FIG. 4 is a plan view showing the state in which a push module of a wafer position alignment device according to the present invention is mounted on a mask plate,

[0033] FIG. 5 is a perspective view showing the structure of a first wafer support applied to the present invention,

[0034] FIG. 6 is a block diagram of a wafer position alignment device according to the present invention,

[0035] FIG. 7 is a perspective view showing the configuration of the push module illustrated in FIG. 6,

[0036] FIG. 8 is a drawing for explaining an example of a state in which a wafer is seated on a first wafer support, a second wafer support, and a third wafer support.

[0037] FIG. 9 is a drawing for explaining a comparative example of the mounting state and operation of a push module,

[0038] FIG. 10 is a drawing for explaining an example of the mounting state and operation of a push module according to the present invention.

[0039] The above and other objects and novel features of the present invention will become more apparent from the description in this specification and the accompanying drawings.

[0040] In the description of the present invention, when a part is described as "comprising" a certain component, this means that, unless specifically stated otherwise, it does not exclude other components but may include additional components. Furthermore, since the size and thickness of each component shown in the description and drawings of the present invention are depicted arbitrarily for convenience of explanation, the present invention is not necessarily limited to what is depicted.

[0041] Additionally, the terms “part,” “module,” or “part” used herein may perform at least one function or operation and may be implemented as hardware or software consisting of mechanical or electrical / electronic configurations, or as a combination of hardware and software; and, excluding the “part,” “module,” or “part” that need to be implemented in specific hardware, the plurality of “parts,” “modules,” or “parts” may be integrated into at least one module and implemented by at least one processor.

[0042] Additionally, in the description of the present invention, terms including ordinal numbers such as first, second, third, etc., may be used to describe various components, but said components are not limited by said terms. Such terms are used solely for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the second component may be named the first component, and similarly, the first component may also be named the second component.

[0043] Meanwhile, the term "wafer" as used herein generally refers to a substrate formed of semiconductor or non-semiconductor materials, non-limiting examples of semiconductor materials include single-crystal silicon, gallium arsenide, and indium phosphide, and such substrates can be typically processed in semiconductor manufacturing facilities, and the substrate may be made of glass, sapphire, or other insulating materials, and "notch" refers to a cutout in a semiconductor wafer that specifies the direction to indicate the crystal orientation.

[0044] Additionally, as used herein, "left-right direction and front-back direction" refers to the X-axis and Y-axis directions as directions parallel to the surface on which the wafer is mounted, and "up-down direction" refers to the Z-axis direction as a direction perpendicular to the horizontal direction formed by the X-axis and Y-axis, and "wafer defect" may include defects such as cracks, defects, or damage in the edge region of the wafer, defects on the surface or inside the wafer, and "wafer defect measurement" may include inspection of the wafer edge region, detection of wafer defects and detection of defect depth, measurement of the type of defect, size of the defect, depth of the defect, and defect image.

[0045] Hereinafter, an embodiment according to the present invention will be described with reference to the drawings.

[0046] FIG. 1 is a configuration diagram of a wafer defect inspection system to which a wafer position alignment device according to the present invention is applied.

[0047] A wafer defect inspection system to which a wafer position alignment device according to the present invention is applied may include a wafer defect measurement module (100), a wafer load module (200), a wafer transfer module (300), and a wafer edge region inspection module (400) as shown in FIG. 1.

[0048] The wafer defect measurement module (100) can mount the wafer (1) on a wafer stage to inspect for defects in the wafer (1). That is, the wafer defect measurement module (100) can detect the defect state of the wafer (1) by light transmitted through the wafer (1). The wafer defect measurement module (100) can be positioned within the stroke area of ​​the robot arm (310) so as to inspect for defects in the wafer (1) as a substrate transported by the robot arm (310).

[0049] The wafer load module (200) may include an inspection load section (210) and a storage load section (220). The inspection load section (210) may be equipped with an inspection wafer cassette on which a plurality of wafers (1), for example, 25 wafers, to be inspected by the wafer defect measurement module (100) are placed. The storage load section (220) may be equipped with a storage wafer cassette on which a plurality of wafers, for example, 25 wafers, that have been inspected according to the present invention are placed.

[0050] The wafer transfer module (300) may be equipped with a robot arm (310) that is mounted on the inspection load portion (210) of the wafer load module (200) to load and unload the wafer (1) to be inspected to the wafer edge region inspection module (400) and the wafer defect measurement module (100). In addition, although the robot arm (310) has been described as having a single robot arm structure in the above description, it is not limited thereto and two or more robot arms may be applied.

[0051] The robot arm (310) may be provided with an edge grip portion for holding the wafer (1) or a vacuum suction portion such as a vacuum chuck. The robot arm (310) may be provided on the main body of the wafer transfer module (300) fixed within the wafer defect inspection system, and may be provided to move up and down and / or move left and right and forward and backward within the stroke area on the main body of the wafer transfer module.

[0052] The wafer edge region inspection module (400) above may be provided as a device for inspecting defects such as cracks, defects, or damage in the edge region of a wafer (1) and for inspecting the edge region of a wafer for aligning notches.

[0053] Meanwhile, the wafer defect measurement module (100) may be provided with a light source module to irradiate light to measure defects on a wafer (1) mounted on a wafer stage. The light source module is provided at the bottom of the wafer stage and may apply NIR (near-infrared) wavelength transmission illumination between 750 nm and 2500 nm to inspect internal defects of the wafer (1). It may include a light guide that can control the light source, light source brightness, and angle.

[0054] The specific structure of the wafer defect measurement module (100) to which the wafer position alignment device according to the present invention is applied will be described with reference to FIG. 2 and FIG. 3. FIG. 2 is a front perspective view of a wafer defect measurement module equipped with a wafer position alignment device according to the present invention, and FIG. 3 is a rear perspective view of a wafer defect measurement module equipped with a wafer position alignment device according to the present invention.

[0055] As shown in FIGS. 2 and 3, the wafer defect measurement module (100) may include a defect detection module (110) that detects the type of defect, the size of the defect, and the defect image of the wafer (1), and a defect depth detection module (120) that detects the depth of the defect detected through the defect detection module (110).

[0056] Additionally, the wafer defect measurement module (100) may include a main body (10) and a gantry (20) as a structure for installing measurement modules, such as a line scan camera and a review camera, on the main body (10). The main body (10) may be provided, for example, as an aluminum plate. A bracket for a line camera, on which a line scan camera (111) for detecting defects in a wafer (1) can be mounted, may be attached to the upper plate of the gantry (20). Additionally, a bracket for a depth camera, on which a depth detection camera (121) can be mounted, may be attached to the outside of the bracket for the line camera. Furthermore, a bracket for fixing the bracket for the line camera and the bracket for the depth camera from the outside may be included.

[0057] The wafer defect measurement module (100) may include a wafer stage for wafer defect inspection. As shown in FIG. 2, the wafer stage is provided in the main body (10) and may include a main table (30) and / or a sub-table (40), a mask plate (50), and a plurality of wafer supports (60).

[0058] The main table (30) is provided to be movable along the Y-axis by a driving member on the upper part of the main body (10), and the sub table (40) can be provided to be movable along the X-axis by the driving member on the upper part of the main table (30).

[0059] As shown in FIG. 2, the sub-table (40) may be equipped with a mask plate (50) formed in a roughly circular shape to block light that may be applied from the outside of the wafer (1) during inspection of the wafer.

[0060] As shown in FIG. 4, an opening (51) corresponding to the wafer (1) is provided in the central part of the mask plate (50), and may be provided corresponding to the outer circumference of the wafer (1). FIG. 4 is a plan view showing the state in which a push module of a wafer position alignment device according to the present invention is mounted on a mask plate.

[0061] In addition, the inner diameter of the mask plate (50) can be provided to be approximately the same size as the outer diameter of the wafer, so that the mask plate (50) does not come into contact with the wafer (1) during inspection but can be provided as close as possible to the wafer.

[0062] As shown in FIGS. 2 and 4, a display cover portion (52) may be provided on the upper part of the mask plate (50) to cover a display portion (e.g., notch portion, flat zone portion) provided on the wafer (1) and to block light irradiated from a light source module provided on the lower part of the main body (10) from leaking.

[0063] The above-mentioned display cover portion (52) may be provided to have a shape corresponding to the notch portion or flat zone portion provided on the wafer, for example, with a front surface in the shape of a triangle, so as to protrude toward the opening (51) of the mask plate (50) to cover the notch portion or flat zone portion provided on the wafer.

[0064] As described above, the mask plate (50) is provided close to the wafer (1), and the inner diameter of the mask plate (50) is provided to be approximately the same size as the outer diameter of the wafer (1). By the display cover portion (52) covering the display portion, light irradiated from the light source module provided at the bottom of the main body (10) is prevented from being irradiated to a part outside the wafer (1) area, thereby enabling precise wafer defect measurement in the wafer defect measurement module (100). That is, by blocking the light irradiated from the light source module from being irradiated to the edge area of ​​the wafer (1) and directly exposed to the camera of the defect measurement module (100), the precision of wafer defect measurement can be increased.

[0065] Additionally, as shown in FIG. 4, a plurality of wafer supports (60) that support the wafer (1) along the periphery of the mask plate (50) in the wafer stage may include a first wafer support (61), a second wafer support (62), and a third wafer support (63). Furthermore, the second wafer support (62) and the third wafer support (63) may be symmetrically arranged with the display cover portion (52) in between, and a push module (500) may be arranged in an isogonal state with respect to the second wafer support (62) and the third wafer support (63). That is, in the triangular structure formed by the push module (500), the second wafer support (62), and the third wafer support (63), the inner angle of the second wafer support (62) and the inner angle of the third wafer support (63) may be provided in a structure where they are identical. The first wafer support (61) may be provided adjacent to the push module (500). Although FIG. 4 shows a structure in which the first wafer support (61) is provided on the right side of the push module (500), it is not limited thereto and may be provided on the left side.

[0066] Additionally, the push module (600) can push the wafer (1) to maintain it in a normal seating state, and as shown in FIG. 4, it can be provided in a position opposite in a straight line to a display cover portion (52) formed corresponding to the notch portion or flat zone portion to cover the notch portion or flat zone portion provided on the wafer (1). Meanwhile, FIG. 4 shows a structure in which three wafer supports (60) are provided, but it is not limited thereto and may be provided in four or more.

[0067] As shown in FIG. 5, the first wafer support (61) includes a seating portion (611) on which the wafer is placed, and the seating portion (611) may be provided as a curved surface so that the wafer (1) can move. FIG. 5 is a perspective view showing the structure of the first wafer support applied to the present invention.

[0068] The above-mentioned mounting portion (611) does not come into contact with the surface of the wafer (1), but can support the wafer (1) from the bottom through the curved space of the mounting portion (611) as shown in FIG. 5, and when the push module (600) is operated, the wafer is transported by about 1 mm, so that a clearance space of about 0.5 to 0.7 mm can be provided. In addition, the push module (600) can realize the function of maintaining the center of the wafer (10) even if the first wafer support (61), the second wafer support (62), and the third wafer support (63) are not arranged vertically.

[0069] Meanwhile, on both sides of the main body (10), a linear servo (510) and an LM guide (520) may be provided between the first and second support plates of the gantry (20) to support the main table (30) so that the main table (30) can be moved along the Y-axis, as shown in FIG. 2. That is, the linear servo (510) is provided to drive the main table (30) along the Y-axis, and the LM guide (520) is provided to support the main table (30) that can be moved along the Y-axis. In addition, as shown in FIG. 3, the sub table (40) is provided to be driven by a servo actuator (530) so as to be movable along the X-axis, and the servo actuator (530) may be operated by being coupled to a clean cable carrier (531) used as a pneumatic tube and wire passage.

[0070] As shown in FIGS. 3 and 4, the mask plate (50) may be provided to be movable in the vertical direction (Z-axis direction) on the sub-table (40) by means of an up-down moving member (540) equipped with an up-down cylinder operated by pneumatic or hydraulic pressure. Accordingly, the mask plate (50) may be provided to be movable in the vertical direction inside the first wafer support (61), the second wafer support (62), the third wafer support (63), and the push module (500) to block light irradiated to the edge area of ​​the wafer (1) during the defect inspection process on the wafer (1). To this end, a cutout for the movement of the mask plate (50) may be provided inside the first wafer support (61), the second wafer support (62), the third wafer support (63), and the push module (500).

[0071] The defect detection module (110) may be provided for inspection to check the size, location, dimensions of the wafer and whether there are microcracks, pinholes, stains (foreign substances), etc., on the surface or back of the wafer. As illustrated in FIGS. 2 and 3, the defect detection module (110) may include a line scan camera (111), a line scan camera control unit (112), and a lens (113) for the line scan camera, and may include a line illumination unit (610) and a line illumination control unit (620) as the light source module. In addition, a plurality of line scan cameras (111) may be provided corresponding to a plurality of line illumination units (610).

[0072] Three line scan cameras (111) can be arranged side by side at regular intervals. The line scan cameras (111) can adjust the position, angle, focal length, etc. of the line scan cameras (111) using the line scan camera adjustment unit (112).

[0073] Next, a wafer position alignment device according to the present invention will be described with reference to FIG. 6.

[0074] FIG. 6 is a block diagram of a wafer position alignment device according to the present invention.

[0075] As illustrated in FIGS. 4 and 6, the wafer position alignment device according to the present invention is a device for aligning the position of a wafer (1) placed on a first wafer support (61), a second wafer support (62), and a third wafer support (63), and may include a judgment module (600) for determining the seating state of the wafer placed on the first wafer support (61) to the third wafer support (63), a push module (500) for pushing the wafer (1) according to the judgment state of the judgment module (600) to maintain the wafer (1) in a normal seating state, a driving module (700) for driving the push module (500), a detection module (800) for detecting the mounting state of the wafer, and a control module (900) for controlling the operation of the driving module (700).

[0076] The above judgment module (600) can determine the state in which a wafer (1) transported by a robot arm (310) as shown in FIG. 1 is placed on a first wafer support (61), a second wafer support (62), and a third wafer support (63) provided on a sub-table (40) of a wafer defect measurement module (100). Such judgment in the judgment module (600) can be determined based on the transport path of the robot arm (310).

[0077] As shown in FIG. 7, the push module (500) may include a pusher (501) for pushing the wafer, a pusher bracket (502) coupled to the pusher (501), a moving member (503) for moving the pusher bracket (502) back and forth, and a holding member (504) provided on the sub-table (40) for holding the moving member (503). FIG. 7 is a perspective view showing the configuration of the push module shown in FIG. 6.

[0078] As shown in FIG. 4, the push module (500) can be provided on the same straight line as the display cover portion (52) and can be provided on the mask plate (50) in an isogonal state with the second wafer support (62) and the third wafer support (63).

[0079] The pusher (501) may be configured to push the wafer placed on the first wafer support (61), the second wafer support (62), and the third wafer support (63) in the direction of the center (G) of the arrangement shape of the second wafer support (62) and the third wafer support (63) which are arranged equiangularly with the push module (500). That is, the pusher (501) may be configured to push in the Y direction which is approximately orthogonal to the X-ray connecting the vertices of the second wafer support (62) and the third wafer support (63).

[0080] The above pusher (501) is a part that comes into direct contact with the wafer (1), and its tip may be formed in a semicircular shape to make point contact with the wafer (1), as shown in FIG. 7. In addition, the pusher (501) may be made of an anti-static (ESD-safe) material to prevent wafer damage and contamination. That is, the pusher (501) is mainly an engineering plastic with anti-static properties, such as PEEK (Polyether Ether Ketone), Delrin, or specially coated ceramic.

[0081] The above pusher bracket (502) can be connected to the upper part of the pusher (501) such that the semicircular tip of the pusher (501) protrudes. The moving member (503) is provided to move the pusher bracket (502) in a straight line in the forward and backward direction (Y-axis direction) by a preset distance and may include a pneumatic cylinder or a hydraulic cylinder. However, it is not limited thereto, and a ball screw member may be applied as the moving member (503). The holding member (504) is provided on the sub-table (40) at the outer circumference of the up-and-down moving mask plate (50) and can hold the moving member (503).

[0082] The above driving module (700) is equipped with a hydraulic fluid tank, a hydraulic pump, a hydraulic motor, etc., and can supply hydraulic fluid to the moving member (503) at regular intervals. The above sensing module (800) may include a sensing camera mounted on the gantry (20), and the sensing camera can photograph the state of the wafer (1) placed on the first wafer support (61), the second wafer support (62), and the third wafer support (63) as shown in FIG. 4.

[0083] The control module (900) may include a microprocessor, memory, etc., and when the judgment module (600) determines that the wafer (1) transported by the robot arm (310) is placed on the first wafer support (61), the second wafer support (62), and the third wafer support (63), the driving module (700) may be operated to control the push module (500) to push the wafer (1) toward the second wafer support (62) and the third wafer support (63).

[0084] In the above description, the structure is described such that the push module (500) is driven when the judgment module (600) determines that the wafer (1) is placed on the first wafer support (61), the second wafer support (62), and the third wafer support (63). However, this is not limited to this, and a structure may be applied in which the push module (500) is driven according to the detection result from the detection module (800) to prevent repetitive operation of the push module (500).

[0085] That is, when the above-mentioned judgment module (600) determines that the wafer (1) transported by the robot arm (310) is placed on the first wafer support (61), the second wafer support (62), and the third wafer support (63), the detection module (800) detects whether the wafer (1) is placed in a normal position, and when the control module (900) determines that it is placed in a normal position, the driving module (700) can be stopped and the defect detection module (110) can be controlled to proceed with defect detection of the wafer. Meanwhile, if the detection result from the detection module (800) determines that the control module (900) determines that the wafer (1) is placed in an abnormal position, the control module (900) can operate the driving module (700) to control the push module (500) to push the wafer (1).

[0086] Next, wafer centering according to the present invention will be described with reference to FIGS. 8 to 10. FIG. 8 is a drawing for explaining an example of a state in which a wafer is seated on a first wafer support, a second wafer support, and a third wafer support; FIG. 9 is a drawing for explaining a comparative example of the mounting state and operation of a push module; and FIG. 10 is a drawing for explaining an example of the mounting state and operation of a push module according to the present invention.

[0087] A wafer (1) transported by a robot arm (310) is placed on a first wafer support (61), a second wafer support (62), and a third wafer support (63), but as shown in FIG. 8, it may be placed abnormally so that the opening (51) is exposed.

[0088] The detection module (800) detects the seating state of the wafer (1) as shown in FIG. 8, and if the control module (900) determines that the wafer (1) is seated in an abnormal position, the control module (900) can operate the driving module (700) to control the push module (500) to push the wafer (1).

[0089] Meanwhile, when the push module (500') of the comparative example shown in FIG. 9 is positioned on the side with a deviation, if the push module (500') pushes the wafer (1) as indicated by the arrow, point contact is made between the second wafer support (62) and the wafer (1) by the pusher operation in the deviation configuration, as indicated by the circular black dot in FIG. 9, and surface contact is made between the third wafer support (63) and the wafer (1), as indicated by the square black dot in FIG. 9, so the opening (51) is exposed and the wafer position alignment may be performed inaccurately. Therefore, the center of the wafer (1) is also deflected toward the 5 o'clock direction, and there was a problem that additional adjustment in the X and Y directions was required.

[0090] In the wafer position alignment device according to the present invention, as shown in FIG. 10, the push module (500) is positioned in an isogonal state with the second wafer support (62) and the third wafer support (63). When the push module (500) pushes the wafer (1) as indicated by the arrow, point contact is performed between the second wafer support (62) and the third wafer support (63) and the wafer (1) by the pusher operation in the isogonal arrangement configuration, as indicated by the circular black dot in FIG. 10, thereby enabling accurate wafer position alignment. Additionally, the center setting of the wafer (1) can also be easily performed by adjusting the Y-axis direction.

[0091] As described above, in the wafer position alignment device according to the present invention, as shown in FIG. 10, the center of the wafer (1) placed on the wafer stage can be aligned to increase positional precision during wafer defect inspection. When the positional precision of the wafer is improved, the advantages of maximizing inspection accuracy and reliability, increasing inspection speed and throughput, and facilitating process control and yield management can be obtained.

[0092] Although the invention made by the inventors has been specifically described according to the above embodiments, the invention is not limited to the above embodiments and can be modified in various ways without departing from the gist thereof.

[0093] By using the wafer position alignment device according to the present invention, the position alignment of the wafer can be easily realized.

Claims

1. A device for aligning the position of a wafer placed on a first wafer support, a second wafer support, and a third wafer support, A judgment module for determining the seating state of a wafer seated on the first to third wafer supports, A push module that pushes the wafer according to the judgment state of the judgment module to maintain the wafer in a normal seating state. A driving module that drives the above push module, A wafer position alignment device characterized by including a control module that controls the operation of the above-mentioned driving module.

2. In Paragraph 1, A wafer position alignment device characterized in that the above-described push module is positioned in an isogonal state with respect to the second wafer support and the third wafer support.

3. In Paragraph 2, A wafer position alignment device characterized in that the above push module is provided at a position opposite in a straight line to a display cover portion formed corresponding to a notch portion or a flat zone portion to cover a notch portion or a flat zone portion provided on the wafer.

4. In Paragraph 2, A wafer position alignment device characterized in that the first wafer support is provided adjacent to the push module.

5. In Paragraph 4, The first wafer support includes a seating portion on which the wafer is placed, and A wafer position alignment device characterized in that the above-described mounting portion is provided as a curved surface to allow the wafer to move.

6. In Paragraph 2, A wafer position alignment device characterized by the above-described push module pushing a wafer mounted on the first wafer support, the second wafer support, and the third wafer support in the direction of the second wafer support and the third wafer support.

7. In Paragraph 2, The above push module is A pusher that pushes the above wafer, Pusher bracket coupled to the above pusher, A moving member that moves the above pusher bracket back and forth, A wafer position alignment device characterized by including a holding member that is provided on a subtable and holds the moving member.

8. In Paragraph 7, The above pusher is made of PEEK (Polyether Ether Ketone). A wafer position alignment device characterized by the following.

9. In Paragraph 7, A wafer position alignment device characterized in that the moving member includes a pneumatic cylinder or a hydraulic cylinder.

10. In Paragraph 7, A wafer position alignment device characterized in that the moving member includes a ball screw member.

11. In Paragraph 1, It further includes a sensing module that detects the seating state of the wafer, and A wafer position alignment device characterized in that the control module controls the operation of the driving module according to the detection result of the detection module.

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