Substrate imaging device

Abstract

The present invention provides a substrate photographing device. Equipment accidents are suppressed, and miniaturization and cost reduction of the substrate photographing device are pursued. The inspection unit (U3) includes: a holding table configured to hold a wafer (W) and rotate the wafer (W); a mirror member (430) having a reflecting surface (432) that is inclined with respect to the rotation axis of the holding table and faces the peripheral region (Wd) of the end face (Wc) and the back face (Wb) of the wafer (W) held on the holding table; and a camera having an imaging element, and light from the peripheral region (Wd) of the surface (Wa) of the wafer (W) held on the holding table and reflected light formed by reflecting light from the end face (Wc) of the wafer (W) held on the holding table by the reflecting surface (432) of the mirror member (430) are both input to the imaging element via a lens.

Description

[0001] This application is a divisional application of a patent application for an invention named "Substrate Photographing Device" with the application number 201710068654.1, the filing date of February 8, 2017. Technical Field

[0002] The present invention relates to a substrate photographing device. Background Art

[0003] Currently, when performing microfabrication of a substrate (e.g., a semiconductor wafer), a lithography technique is widely used to form a concavo-convex pattern on the substrate. For example, the process of forming a resist pattern on a semiconductor wafer includes forming a resist film on the surface of the wafer, exposing the resist film according to a predetermined pattern, and developing the exposed resist film by reacting it with a developer.

[0004] In recent years, as a technique for obtaining an extremely fine resist pattern with a line width of about 40 nm to 45 nm, a liquid immersion exposure technique has been proposed. When performing liquid immersion exposure of a resist film, exposure of the resist film is performed in a state where an exposure liquid (such as pure water) having a refractive index higher than that of air is supplied between the wafer and a projection lens for exposure.

[0005] However, during the process of surface treatment of a wafer, due to various reasons, minute particles (foreign matters) sometimes adhere to the surface (central portion or peripheral portion) of the wafer. By cleaning the surface of the substrate with a cleaning liquid, most of the particles can be removed, but sometimes particles still remain on the surface of the substrate. If a wafer with adhered particles is input into an exposure machine, the exposure machine is contaminated by the particles, and in subsequent exposure of the wafer, in addition to the desired pattern, the shape of the particles can also be replicated. In addition, if the exposure machine is contaminated by particles, cleaning of the exposure machine sometimes takes a long time, and the productivity is greatly reduced. Moreover, in the case where there are originally defects (e.g., cracks, breakages, damages, etc.) near the periphery of the wafer, the wafer cannot be properly processed. Therefore, Patent Documents 1 to 3 disclose a method for inspecting a wafer, which includes a step of photographing the peripheral portion of the wafer using a plurality of cameras, a step of performing image processing on each captured image, and a step of grasping the state of the peripheral portion of the wafer based on the processed image after image processing.

[0006] Prior Art Documents

[0007] Patent Documents

[0008] Patent Document 1: Japanese Patent Application Laid-Open No. 2007-251143

[0009] Patent Document 2: Japanese Patent Application Laid-Open No. 2008-135583

[0010] Patent Document 3: Japanese Patent Laid-Open No. 11-339042 Summary of the Invention

[0011] Problems to be Solved by the Invention

[0012] However, in the inspection methods of Patent Documents 1 to 3, in order to inspect a plurality of surfaces (for example, the upper surface and the end surface) near the periphery of the wafer, a plurality of cameras are used and each surface is independently photographed. Therefore, a space for setting a plurality of cameras is required, the apparatus for inspecting the wafer may be enlarged, and the cost of the apparatus may increase.

[0013] It is also conceivable to inspect a plurality of surfaces near the periphery of the wafer while moving one camera, but a space for setting a mechanism for moving the camera is required, so the apparatus may still be enlarged. In addition, the moving speed of the camera is not so fast, so the inspection of the wafer may take time.

[0014] Moreover, in the case of using a plurality of cameras, in addition to the plurality of cameras, an assembly mechanism thereof is required, etc., and the structure becomes complicated. In the case of moving one camera, in addition to one camera, a moving mechanism of the camera is required, etc., and the structure becomes complicated. Therefore, in the inspection methods of Patent Documents 1 to 3, the possibility of equipment accidents such as failures increases, and it may not be possible to perform inspections efficiently.

[0015] Therefore, the present invention describes a substrate photographing apparatus that can suppress equipment accidents and aims for miniaturization and cost reduction.

[0016] Solutions for Solving the Problems

[0017] A substrate photographing apparatus according to one aspect of the present invention includes: a rotation holding unit configured to hold a substrate and rotate the substrate; a mirror member having a reflection surface that is inclined with respect to the rotation axis of the rotation holding unit and faces the peripheral regions of the end surface and the back surface of the substrate held by the rotation holding unit; and a camera having a photographing element, and first light from the peripheral region of the surface of the substrate held by the rotation holding unit and reflected light formed by reflecting second light from the end surface of the substrate held by the rotation holding unit by the mirror member are input to the photographing element via a lens.

[0018] In the substrate photographing apparatus according to one aspect of the present invention, the mirror member has a reflecting surface that is inclined with respect to the rotation axis of the rotation holding portion and faces the peripheral regions of the end surface and the back surface of the substrate held by the rotation holding portion. Further, in the substrate photographing apparatus according to one aspect of the present invention, the first light from the peripheral region of the surface of the substrate held by the rotation holding portion and the second light from the end surface of the substrate held by the rotation holding portion are reflected by the reflecting surface of the mirror member, and the reflected light is input to the photographing element of the camera via the lens. Therefore, both the peripheral region of the surface of the substrate and the end surface of the substrate are photographed simultaneously by one camera. Thus, there is no need for a plurality of cameras, and as a result, there is also no need for a space for arranging the plurality of cameras. In addition, there is no need for a mechanism for moving the camera, and therefore, there is also no need for a space for arranging the mechanism. In this way, in the substrate photographing apparatus according to one aspect of the present invention, the apparatus structure is extremely simplified. As a result, equipment accidents can be suppressed, and miniaturization and cost reduction of the substrate photographing apparatus can be achieved.

[0019] The reflecting surface may be a curved surface that is recessed toward the side away from the end surface of the substrate held by the rotation holding portion. In this case, the mirror image of the end surface of the substrate reflected on the reflecting surface is magnified compared to the real image. Therefore, a more detailed photographed image of the end surface of the substrate can be obtained. Thus, by performing image processing on the photographed image, the end surface of the substrate can be inspected more accurately.

[0020] Alternatively, the substrate photographing apparatus according to one aspect of the present invention may further include a focus adjustment lens configured to be disposed in the middle of the optical path between the reflection of the second light by the reflecting surface of the mirror member and the arrival at the lens, and to align the imaging position of the end surface of the substrate with the photographing element. The optical path of the second light reflected by the reflecting surface of the mirror member and reaching the lens is longer than the optical path of the first light reaching the lens by an amount corresponding to the reflection by the mirror member. However, in this case, since the focus adjustment lens aligns the imaging position of the end surface of the substrate with the photographing element, both the peripheral region of the surface of the substrate and the end surface of the substrate in the photographed image become clear. Thus, by performing image processing on the photographed image, the end surface of the substrate can be inspected more accurately.

[0021] Alternatively, the substrate photographing apparatus according to one aspect of the present invention further includes an illumination unit having: a light source; and a light diffusion member that diffuses the light from the light source in a first direction orthogonal to the optical axis of the light from the light source to generate diffused light. The illumination unit irradiates the diffused light onto the peripheral region of the surface of the substrate held by the rotary holding unit, and irradiates the diffused light onto the reflecting surface of the mirror member such that the reflected light obtained by reflecting the diffused light by the mirror member reaches the end surface of the substrate held by the rotary holding unit. In this case, since the light from the light source is diffused in the first direction, the diffused light enters the end surface of the substrate from various directions. Therefore, the entire end surface of the substrate is uniformly illuminated. Thus, the end surface of the substrate can be photographed more clearly.

[0022] Alternatively, the illumination unit further includes: a light scattering member that scatters the light from the light source to generate scattered light; and a cylindrical lens that is convex toward the light diffusion member and transmits the scattered light from the light scattering member through the light diffusion member. The cylindrical lens diffuses the scattered light from the light scattering member in a second direction orthogonal to both the optical axis of the light from the light source and the first direction. In this case, since the scattered light is diffused in the first direction and the second direction, the diffused light enters the end surface of the substrate from various directions. Therefore, the entire end surface of the substrate is more uniformly illuminated. Thus, the end surface of the substrate can be photographed even more clearly.

[0023] Effects of the Invention

[0024] According to the substrate photographing apparatus of the present invention, equipment accidents can be suppressed, and miniaturization and cost reduction can be achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 is a perspective view showing a substrate processing system.

[0026] Figure 2 is Figure 1 a sectional view taken along line II-II of

[0027] Figure 3 is a top view showing unit processing modules (BCT module, HMCT module, COT module, and DEV module).

[0028] Figure 4 is a sectional view of the inspection unit as viewed from above.

[0029] Figure 5 is a sectional view of the inspection unit as viewed from the side.

[0030] Figure 6 is a perspective view showing the inspection unit.

[0031] Figure 7 is a perspective view of the peripheral photographing sub-unit as viewed from the front.

[0032] Figure 8 It is a perspective view of the peripheral shooting sub-unit taken from the rear.

[0033] Figure 9 It is a top view of the peripheral shooting sub-unit.

[0034] Figure 10 It is a side view of the two-sided shooting module.

[0035] Figure 11 It is an exploded perspective view showing the illumination module.

[0036] Figure 12 It is Figure 11 a cross-sectional view taken along line XII-XII.

[0037] Figure 13 It is Figure 11 a cross-sectional view taken along line XIII-XIII.

[0038] Figure 14 (a) of is a photograph showing the situation when light from the light source passes through the light scattering member, Figure 14 of (b) is a photograph showing the situation when light from the light source passes through the light scattering member and the cylindrical lens, Figure 14 of (c) is a photograph showing the situation when light from the light source passes through the light scattering member, the cylindrical lens, and the light diffusion member.

[0039] Figure 15 (a) of is a diagram for explaining the optical path in the case where there is no focus adjustment lens, Figure 15 of (b) is a diagram for explaining the optical path in the case where there is a focus adjustment lens.

[0040] Figure 16 It is a perspective view showing the mirror member.

[0041] Figure 17 It is a side view of the mirror member.

[0042] Figure 18 (a) of is a diagram for explaining the situation where light from the illumination module is reflected in the mirror member, Figure 18 of (b) is a diagram for explaining the situation where light from the wafer is reflected in the mirror member.

[0043] Figure 19 (a) of shows the captured image when focusing on the surface of the wafer in the case where there is no focus adjustment lens, Figure 19 of (b) shows the captured image when focusing on the end face of the wafer in the case where there is no focus adjustment lens, Figure 19The (c) shows a captured image when focusing on both the surface and the end face of the wafer in the presence of the focus adjustment lens.

[0044] Figure 20 It is a side view of the backside imaging sub-unit.

[0045] Figure 21 It is a block diagram showing the main part of the substrate processing system.

[0046] Figure 22 It is a schematic diagram showing the hardware configuration of the controller.

[0047] Explanation of Reference Numerals

[0048] 1. Substrate processing system (substrate processing apparatus); 2. Coating and developing apparatus (substrate processing apparatus); 10. Controller (control unit); 14 - 17. Unit processing modules; 200. Rotation and holding sub-unit (rotation and holding unit); 201. Holding table; 300. Surface imaging sub-unit; 400. Peripheral imaging sub-unit (substrate imaging apparatus); 500. Backside imaging sub-unit; 310, 410, 510. Cameras; 411, 511. Lenses; 412, 512. Imaging elements; 320, 420, 520. Lighting modules (lighting units); 322, 421, 522. Light sources; 422. Light scattering member; 425. Cylindrical lens; 426. Light diffusing member; 427. Focus adjustment lens; 430. Mirror member; 432. Reflective surface; M2. Storage unit; M3. Processing unit; RM. Recording medium; U3. Inspection unit; W. Wafer (substrate); Wa. Surface; Wb. Backside; Wc. End face; Wd. Peripheral region. Detailed Embodiments

[0049] The embodiments of the present invention described below are illustrative of the present invention, and thus the present invention should not be limited to the following content. In the following description, the same reference numerals are used for the same elements or elements having the same functions, and repeated descriptions are omitted.

[0050] [Substrate Processing System]

[0051] As Figure 1 shown, the substrate processing system 1 (substrate processing apparatus) includes a coating and developing apparatus 2 (substrate processing apparatus) and a controller 10 (control unit). The substrate processing system 1 is arranged in parallel with the exposure apparatus 3. The exposure apparatus 3 has a controller (not shown) that can communicate with the controller 10 of the substrate processing system 1. The exposure apparatus 3 is configured to transfer the wafer W (substrate) between it and the coating and developing apparatus 2 and perform operations on the surface Wa of the wafer W (refer to Figure 10Exposure processing (pattern exposure) of a photosensitive resist film formed by (etc.). Specifically, an energy beam is selectively irradiated onto the exposure target portion of the photosensitive resist film (photosensitive coating film) by a method such as immersion exposure. Examples of the energy beam include an ArF excimer laser, a KrF excimer laser, a g-line, an i-line, or extreme ultraviolet (EUV: Extreme Ultraviolet).

[0052] The coating / development apparatus 2 performs a process of forming a photosensitive resist film or a non-photosensitive resist film (hereinafter, collectively referred to as "resist film") on the surface Wa of the wafer W before the exposure processing performed by the exposure apparatus 3. The coating / development apparatus 2 performs a development process of the photosensitive resist film after the exposure processing of the photosensitive resist film performed by the exposure apparatus 3.

[0053] The wafer W may be in the shape of a circular plate or in the shape of a plate other than a circle such as a polygon. The wafer W may also have a notch portion formed by cutting off a part thereof. The notch portion may be, for example, a notch (a groove such as a U-shape or a V-shape) or a linear portion (so-called orientation flat) extending linearly. The wafer W may also be various other substrates such as a semiconductor substrate, a glass substrate, a mask substrate, or an FPD (Flat Panel Display) substrate. The diameter of the wafer W may be, for example, about 200 mm to 450 mm. In addition, when a bevel (chamfer) exists at the edge of the wafer W, the "surface" in this specification also includes the bevel portion when viewed from the surface Wa side of the wafer W. Similarly, the "back surface" in this specification also includes the bevel portion when viewed from the back surface Wb (refer to Figure 10 etc.) side of the wafer W. The "end face" in this specification also includes the bevel portion when viewed from the end face Wc (refer to Figure 10 etc.) side of the wafer W.

[0054] As Figures 1 to 3 shown, the coating / development apparatus 2 includes a carrier module 4, a processing module 5, and a transfer module 6. The carrier module 4, the processing module 5, and the transfer module 6 are arranged in the horizontal direction.

[0055] As Figure 1 and Figure 3 shown, the carrier module 4 includes a carrier station 12 and an input / output unit 13. The carrier station 12 supports a plurality of carriers 11. Each carrier 11 houses at least one wafer W in a sealed state. An opening / closing door (not shown) for allowing the wafer W to enter and exit is provided on the side surface 11a of the carrier 11. The carrier 11 is detachably provided on the carrier station 12 with the side surface 11a facing the input / output unit 13.

[0056] The input / output unit 13 is located between the carrier station 12 and the processing module 5. The input / output unit 13 has a plurality of opening / closing doors 13a. When the carrier 11 is placed on the carrier station 12, the opening / closing doors of the carrier 11 face the opening / closing doors 13a. By simultaneously opening the opening / closing doors 13a and the opening / closing doors on the side 11a, the inside of the carrier 11 and the inside of the input / output unit 13 are communicated. The input / output unit 13 is internally provided with a transfer arm A1. The transfer arm A1 takes out the wafer W from the carrier 11 and transfers the wafer W to the processing module 5, and receives the wafer W from the processing module 5 and returns the wafer W to the inside of the carrier 11.

[0057] As Figure 1 and Figure 2 shown, the processing module 5 has unit processing modules 14 to 17. The unit processing modules 14 to 17 are arranged in the order of unit processing module 17, unit processing module 14, unit processing module 15, and unit processing module 16 from the ground side. As Figure 3 shown, the unit processing modules 14 to 17 have a liquid processing unit U1, a heat processing unit U2, and an inspection unit U3.

[0058] The liquid processing unit U1 is configured to supply various processing liquids to the surface Wa of the wafer W. The heat processing unit U2 is configured to perform heat processing on the wafer W by heating the wafer W using, for example, a hot plate and cooling the heated wafer W using, for example, a cooling plate. The inspection unit U3 is configured to inspect each surface (surface Wa, back surface Wb, and end surface Wc) of the wafer W (details will be described later).

[0059] The unit processing module 14 is a lower layer film forming module (BCT module) configured to form a lower layer film on the surface Wa of the wafer W. The unit processing module 14 is internally provided with a transfer arm A2 that transfers the wafer W to each of the units U1 to U3 (refer to Figure 2 ). The liquid processing unit U1 of the unit processing module 14 coats the surface Wa of the wafer W with a coating liquid for forming a lower layer film to form a coating film. The heat processing unit U2 of the unit processing module 14 performs various heat treatments associated with the formation of the lower layer film. As a specific example of the heat treatment, a heating treatment for hardening the coating film to form a lower layer film can be cited. As the lower layer film, for example, an anti-reflection (SiARC) film can be cited.

[0060] The unit processing module 15 is an intermediate film (hard mask) forming module (HMCT module) configured to form an intermediate film on the lower layer film. The unit processing module 15 is internally provided with a transfer arm A3 that transfers the wafer W to each of the units U1 to U3 (refer to Figure 2)。The liquid processing unit U1 of the unit processing module 15 coats the lower layer film with the coating liquid for forming the intermediate film to form a coated film. The heat treatment unit U2 of the unit processing module 15 performs various heat treatments associated with the formation of the intermediate film. As a specific example of the heat treatment, a heat treatment for hardening the coated film to form the intermediate film can be cited. As the intermediate film, for example, an SOC (Spin On Carbon) film or an amorphous carbon film can be cited.

[0061] The unit processing module 16 is a resist film forming module (COT module) configured to form a thermosetting resist film on the intermediate film. The unit processing module 16 is internally provided with a transfer arm A4 for transferring the wafer W to each of the units U1 to U3 (refer to Figure 2 ). The liquid processing unit U1 of the unit processing module 16 coats the intermediate film with the coating liquid (resist agent) for forming the resist film to form a coated film. The heat treatment unit U2 of the unit processing module 16 performs various heat treatments associated with the formation of the resist film. As a specific example of the heat treatment, a heat treatment (pre-bake, PAB: Pre Applied Bake) for hardening the coated film to form the resist film can be cited.

[0062] The unit processing module 17 is a development processing module (DEV module) configured to perform development processing of the exposed resist film. The unit processing module 17 is internally provided with a transfer arm A5 for transferring the wafer W to each of the units U1 to U3 and a direct transfer arm A6 for transferring the wafer W without passing through these units (refer to Figure 2 ). The liquid processing unit U1 of the unit processing module 17 supplies a developer to the exposed resist film to develop the resist film. The liquid processing unit U1 of the unit processing module 17 supplies a rinse liquid to the developed resist film to rinse the dissolved components of the resist film together with the developer. Thereby, the resist film is locally removed to form a resist pattern. The heat treatment unit U2 of the unit processing module 16 performs various heat treatments associated with the development processing. As specific examples of the heat treatment, a heat treatment before the development processing (post-exposure bake, PEB), a heat treatment after the development processing (post-bake, PB), etc. can be cited.

[0063] As Figure 2 and Figure 3 shown, a shelf unit U10 is provided on the side of the processing module 5 closer to the carrier module 4. The shelf unit U10 is provided from the ground to the unit processing module 16 and is divided into a plurality of compartments arranged in the vertical direction. A lifting arm A7 is provided near the shelf unit U10. The lifting arm A7 raises and lowers the wafer W between the compartments of the shelf unit U10.

[0064] A shelf unit U11 is provided on the side of the transfer module 6 within the processing module 5. The shelf unit U11 is provided from the ground to the upper part of the unit processing module 17 and is divided into a plurality of compartments arranged in the vertical direction.

[0065] The transfer module 6 is internally provided with a transfer arm A8, which is connected to the exposure device 3. The transfer arm A8 is configured to take out the wafer W of the shelf unit U11 and hand it over to the exposure device 3, and receive the wafer W from the exposure device 3 to return the wafer W to the shelf unit U11.

[0066] The controller 10 controls the substrate processing system 1 locally or integrally. The details of the controller 10 will be described later. In addition, the controller 10 can transmit and receive signals between itself and the controller of the exposure device 3, and control the substrate processing system 1 and the exposure device 3 by the cooperation of each controller.

[0067] [Structure of the inspection unit]

[0068] Next, with reference to Figures 4 to 20 , the inspection unit U3 will be described in further detail. As Figures 4 to 6 shown, the inspection unit U3 includes a housing 100, a rotation holding sub-unit 200 (rotation holding part), a surface photographing sub-unit 300, a peripheral photographing sub-unit 400 (substrate photographing device), and a back surface photographing sub-unit 500. Each sub-unit 200 - 500 is arranged within the housing 100. An input / output port 101 for inputting the wafer W into the housing 100 and outputting it from the housing 100 is formed in one end wall of the housing 100.

[0069] The rotation holding sub-unit 200 includes a holding table 201, actuators 202, 203, and a guide rail 204. The holding table 201 is an adsorption chuck that holds the wafer W substantially horizontally by, for example, adsorption. There is no particular limitation on the shape of the holding table 201 (adsorption chuck), but it can be, for example, circular. The size of the holding table 201 can also be smaller than the size of the wafer W.

[0070] The actuator 202 is, for example, an electric motor that drives the holding table 201 to rotate the holding table 201. That is, the actuator 202 rotates the wafer W held on the holding table 201. The actuator 202 can also include an encoder for detecting the rotation position of the holding table 201. In this case, the photographing positions of each surface of the wafer W by each photographing sub-unit 300, 400, 500 can be made to correspond to the rotation position. In the case where the wafer W has a notch, the posture of the wafer W can be determined based on the notch discriminated by each photographing sub-unit 300, 400, 500 and the rotation position detected by the encoder.

[0071] The actuator 203 is, for example, a linear actuator, and moves the holding table 201 along the guide rail 204. That is, the actuator 203 transports the wafer W held on the holding table 201 between one end side and the other end side of the guide rail 204. Therefore, the wafer W held on the holding table 201 can move between a first position close to the input / output port 101 and a second position close to the peripheral imaging sub-unit 400 and the back imaging sub-unit 500. The guide rail 204 extends in a linear shape (for example, a straight line) inside the housing 100.

[0072] The surface photographing sub-unit 300 includes a camera 310 (photographing component) and an illumination module 320. The camera 310 and the illumination module 320 constitute a set of photographing modules. The camera 310 includes a lens and an imaging element (for example, a CCD image sensor, a CMOS image sensor, etc.). The camera 310 is opposite to the illumination module 320 (illumination unit).

[0073] The lighting module 320 includes a semi-transparent reflector 321 and a light source 322. The semi-transparent reflector 321 is arranged in the housing 100 in a state of being inclined at approximately 45° relative to the horizontal direction. The semi-transparent reflector 321 is located above the middle portion of the guide rail 204 in a manner that intersects with the extension direction of the guide rail 204 when viewed from above. The semi-transparent reflector 321 is rectangular in shape. The length of the semi-transparent reflector 321 is greater than the diameter of the wafer W.

[0074] The light source 322 is located above the semi-transparent mirror 321. The light source 322 is longer than the semi-transparent mirror 321. The light emitted from the light source 322 passes through the semi-transparent mirror 321 as a whole and is irradiated downward (toward the guide rail 204). The light that has passed through the semi-transparent mirror 321 is reflected by an object located below the semi-transparent mirror 321, and then is reflected again by the semi-transparent mirror 321, and is incident on the imaging element of the camera 310 through the lens of the camera 310. That is, the camera 310 can photograph an object existing in the irradiation area of ​​the light source 322 through the semi-transparent mirror 321. For example, when the holding table 201 holding the wafer W is moved along the guide rail 204 by the actuator 203, the camera 310 can photograph the surface Wa of the wafer W passing through the irradiation area of ​​the light source 322. The data of the captured image captured by the camera 310 is sent to the controller 10.

[0075] like Figures 4 to 10 As shown, the peripheral shooting sub-unit 400 includes a camera 410 (shooting component), an illumination module 420 and a mirror member 430. The camera 410, the illumination module 420 (illumination unit) and the mirror member 430 constitute a set of shooting modules. The camera 410 includes a lens 411 and a shooting element 412 (for example, a CCD image sensor, a CMOS image sensor, etc.). The camera 410 is opposite to the illumination module 420.

[0076] As shown in Figures 7 to 13 FIG. 4, the illumination module 420 is disposed above the wafer W held on the holding table 201. The illumination module 420 includes a light source 421, a light scattering member 422, and a holding member 423. As shown in Figures 11 to 13 FIG. 5, the light source 421 includes, for example, a housing 421a and a plurality of LED point light sources 421b disposed within the housing 421a. The plurality of LED point light sources 421b are arranged in a row along the radial direction of the wafer W.

[0077] As shown in Figures 7 to 13 FIG. 6, the light scattering member 422 is connected to the light source 421 so as to overlap with the light source 421. As shown in Figures 11 to 13 FIG. 7, a through hole 422a extending in the direction in which the light source 421 and the light scattering member 422 overlap is formed in the light scattering member 422. The inner wall surface of the through hole 422a is subjected to mirror finishing. As a method of mirror finishing, for example, a method of performing electroless nickel plating on the inner wall surface to form a plating film 422b on the inner wall surface can be cited. Thus, when the light from the light source 421 enters the through hole 422a of the light scattering member 422, as shown in Figure 12 and Figure 13 FIG. 8, the incident light is diffusely reflected on the plating film 422b. Thus, scattered light is generated in the light scattering member 422 (refer to (a) of Figure 14 FIG. 9).

[0078] As shown in Figures 7 to 13 FIG. 10, the holding member 423 is connected to the light scattering member 422 so as to overlap with the light scattering member 422. As shown in Figures 10 to 13 FIG. 11, a through hole 423a and an intersecting hole 423b intersecting with the through hole 423a are formed in the holding member 423. The through hole 423a extends in the direction in which the light scattering member 422 and the holding member 423 overlap. The intersecting hole 423b extends from one side surface of the holding member 423 toward the through hole 423a in a direction orthogonal to the through hole 423a. The intersecting hole 423b is connected so as to communicate with the through hole 423a.

[0079] As shown in Figures 7 to 13 FIG. 12, the holding member 423 internally holds a semi-transparent mirror 424, a cylindrical lens 425, a light diffusion member 426, and a focus adjustment lens 427. As shown in Figure 10 and Figure 12 FIG. 13, the semi-transparent mirror 424 is disposed at the intersection of the through hole 423a and the intersecting hole 423b in a state inclined by approximately 45° with respect to the horizontal direction. The semi-transparent mirror 424 has a rectangular shape.

[0080] As shown in Figures 10 to 13As shown, the cylindrical lens 425 is disposed between the light scattering member 422 and the semi-transmissive mirror 424. As Figures 10 to 12 shown, the cylindrical lens 425 is a convex cylindrical lens protruding toward the semi-transmissive mirror 424. The axis of the cylindrical lens 425 extends along the direction in which the plurality of LED point light sources 421b are arranged. When the scattered light from the light scattering member 422 is incident on the cylindrical lens 425, the scattered light is magnified in the circumferential direction along the cylindrical surface of the cylindrical lens 425 (refer to Figure 14 (b) of

[0081] As Figures 10 to 13 shown, the light diffusing member 426 is disposed between the cylindrical lens 425 and the semi-transmissive mirror 424. The light diffusing member 426 is a sheet member having a rectangular shape and diffuses the light that has passed through the cylindrical lens 425. Thereby, diffused light is generated in the light diffusing member 426 (refer to Figure 14 (c) of

[0082] As Figure 7 , Figure 8 , Figure 11 and Figure 12 shown, the focus adjustment lens 427 is disposed within the cross hole 423b. The focus adjustment lens 427 is not particularly limited as long as it is a lens having a function of changing the combined focal length with the lens 411. The focus adjustment lens 427 is a lens having, for example, a rectangular parallelepiped shape.

[0083] Here, when only the lens 411 is used, as Figure 15 (a) of Figure 15As shown in (b) of FIG. 0, the light from point B away from the lens 411 is refracted by the focus adjustment lens 427 and then condensed onto the imaging element 412 via the lens 411. Due to the presence of the focus adjustment lens 427, when observing the image of point B through the focus adjustment lens 427, it can be seen that the image exists at point C on the same plane as point A. Therefore, when observed from the lens 411, the distances of the positions of point A and the apparent position of point B (the position of point C) from the lens 411 are equal. Thus, the light from point A and point B is condensed onto the imaging element 412. Consequently, the images of point A and point B are clearly projected onto the imaging element 412. In addition, the above description is equally applicable to the case of a dual-focus lens (bifocal lens) in which the focus adjustment lens 427 has two parts with different refractive powers within one lens.

[0084] As Figure 7 , Figure 10 , Figure 12 , Figure 13 and Figure 16 shown, the mirror member 430 is disposed below the illumination module 420. As Figure 7 , Figure 10 , Figure 12 , Figure 13 , Figure 16 and Figure 17 shown, the mirror member 430 includes a main body 431 and a reflecting surface 432. The main body 431 is composed of an aluminum module.

[0085] As Figure 7 , Figure 13 and Figure 17 shown, when the wafer W held on the holding table 201 is in the second position, the reflecting surface 432 faces the peripheral region Wd of the end face Wc and the back face Wb of the wafer W held on the holding table 201. The reflecting surface 432 is inclined with respect to the rotation axis of the holding table 201. The reflecting surface 432 has been subjected to mirror finishing. For example, a lens may be pasted on the reflecting surface 432, or aluminum plating may have been performed, or an aluminum material may have been vapor-deposited.

[0086] The reflecting surface 432 is a curved surface that is recessed toward the side away from the end face Wc of the wafer W held on the holding table 201. That is, the mirror member 430 is a concave mirror. Therefore, if the end face Wc of the wafer W is projected onto the reflecting surface 432, its mirror image is magnified compared to the real image. The radius of curvature of the reflecting surface 432 may be, for example, about 10 mm to 30 mm. The opening angle θ of the reflecting surface 432 (refer to Figure 17 ) may also be about 100° to 150°. In addition, the opening angle θ of the reflecting surface 432 refers to the angle formed by two planes circumscribing the reflecting surface 432.

[0087] In the illumination module 420, the light emitted from the light source 421 is scattered by the light scattering member 422, magnified by the cylindrical lens 425, and then diffused by the light diffusing member 426, and then irradiated downward as a whole through the semi-transparent mirror 424. The diffused light that has passed through the semi-transparent mirror 424 is reflected by the reflecting surface 432 of the mirror member 430 located below the semi-transparent mirror 424. When the wafer W held on the holding table 201 is in the second position, as Figure 13 and Figure 18 shown in (a), the reflected light formed by the reflection of the diffused light by the reflecting surface 432 is mainly irradiated onto the end surface Wc of the wafer W (especially the upper end side of the inclined surface portion when there is an inclined surface at the edge of the wafer W) and the peripheral region Wd of the surface Wa.

[0088] The reflected light reflected from the peripheral region Wd of the surface Wa of the wafer W is not directed toward the reflecting surface 432 of the mirror member 430 but is reflected again by the semi-transparent mirror 424 (see Figure 18 in (b)), passes through the lens 411 of the camera 410 without passing through the focus adjustment lens 427, and is incident on the imaging element 412 of the camera 410. On the other hand, the reflected light reflected from the end surface Wc of the wafer W is reflected successively by the reflecting surface 432 of the mirror member 430 and the semi-transparent mirror 424, passes through the focus adjustment lens 427 and the lens 411 of the camera 410 successively, and is incident on the imaging element 412 of the camera 410. Therefore, the optical path of the light reaching the imaging element 412 of the camera 410 from the end surface Wc of the wafer W is longer than the optical path of the light reaching the imaging element 412 of the camera 410 from the peripheral region Wd of the surface Wa of the wafer W. The optical path difference between these optical paths can be, for example, about 1 mm to 10 mm. In this way, both the light from the peripheral region Wd of the surface Wa of the wafer W and the light from the end surface Wc of the wafer W are input to the imaging element 412 of the camera 410. That is, when the wafer W held on the holding table 201 is in the second position, the camera 410 can image both the peripheral region Wd of the surface Wa of the wafer W and the end surface Wc of the wafer W. The data of the captured image captured by the camera 410 is sent to the controller 10.

[0089] In addition, when focusing on the peripheral region Wd of the surface Wa of the wafer W without the focus adjustment lens 427, due to the existence of this optical path difference, in the captured image captured by the camera 410, there is a tendency that the peripheral region Wd of the surface Wa of the wafer W is clearly imaged while the end surface Wc of the wafer W is blurred (see Figure 19On the other hand, in the case where the focus adjustment lens 427 is not present and the light is focused on the end face Wc of the wafer W, due to the existence of this optical path difference, in the captured image captured by the camera 410, there is a tendency that the end face Wc of the wafer W is clearly imaged while the peripheral region Wd of the surface Wa of the wafer W is blurred (refer to Figure 19 of (b)). However, since the focus adjustment lens 427 exists between the reflected light reflected by the reflecting surface 432 of the mirror member 430 and the lens 411, even if this optical path difference exists, the imaging position of the end face Wc of the wafer W is aligned with the imaging element 412 (refer to Figure 15 of (b)). Therefore, in the captured image captured by the camera 410, both the peripheral region Wd of the surface Wa of the wafer W and the end face Wc of the wafer W are clearly imaged (refer to Figure 19 of (c)).

[0090] As Figures 4 to 9 and Figure 20 shown, the back surface photographing sub-unit 500 includes a camera 510 (photographing component) and an illumination module 520 (illumination unit). The camera 510 and the illumination module 520 constitute a set of photographing modules. The camera 510 includes a lens 511 and an imaging element 512 (for example, a CCD image sensor, a CMOS image sensor, etc.). The camera 510 faces the illumination module 520 (illumination unit).

[0091] The illumination module 520 is disposed below the illumination module 420 and below the wafer W held on the holding table 201. As Figure 20 shown, the illumination module 520 includes a semi-transparent mirror 521 and a light source 522. The semi-transparent mirror 521 is disposed in a state inclined by approximately 45° with respect to the horizontal direction. The semi-transparent mirror 521 has a rectangular shape.

[0092] The light source 522 is located below the semi-transparent mirror 521. The light source 522 is longer than the semi-transparent mirror 521. The light emitted from the light source 522 is irradiated upward as a whole through the semi-transparent mirror 521. After the light passing through the semi-transparent mirror 521 is reflected by an object located above the semi-transparent mirror 521, it is reflected again by the semi-transparent mirror 521, passes through the lens 511 of the camera 510, and enters the imaging element 512 of the camera 510. That is, the camera 510 can photograph an object existing in the irradiation area of the light source 522 by means of the semi-transparent mirror 521. For example, when the wafer W held on the holding table 201 is in the second position, the camera 510 can photograph the back surface Wb of the wafer W. The data of the captured image captured by the camera 510 is sent to the controller 10.

[0093] [Configuration of the controller]

[0094] As Figure 21 shown, the controller 10 has a reading unit M1, a storage unit M2, a processing unit M3, and an instruction unit M4 as functional modules. These functional modules are merely for convenience to divide the functions of the controller 10 into multiple modules, and do not necessarily mean that the hardware constituting the controller 10 is divided into such modules. Each functional module is not limited to a module that can be implemented by the execution of a program, and can also be a module implemented by a dedicated circuit (such as a logic circuit), or an integrated circuit (ASIC: Application Specific Integrated Circuit) formed by integrating them.

[0095] The reading unit M1 reads a program from a computer-readable recording medium RM. The recording medium RM records a program for operating each part of the substrate processing system 1. As the recording medium RM, for example, a semiconductor memory, an optical disc, a magnetic disk, or an optical magnetic disk can be used.

[0096] The storage unit M2 stores various data. In addition to storing, for example, the program read from the recording medium RM by the reading unit M1 and the data of the captured images captured by the cameras 310, 410, and 510, the storage unit M2 also stores various data (so-called processing processes) for processing the wafer W, setting data input by an operator through an external input device (not shown), and the like.

[0097] The processing unit M3 processes various data. The processing unit M3 generates signals for operating the liquid processing unit U1, the heat processing unit U2, and the inspection unit U3 (for example, the rotation holding sub-unit 200, the cameras 310, 410, 510, the illumination modules 320, 420, 520) based on, for example, various data stored in the storage unit M2. In addition, the processing unit M3 performs image processing on the data of the captured images captured by the cameras 310, 410, and 510, and judges whether there are defects in the wafer W or the like. When the processing unit M3 determines that there are defects in the wafer W or the like, it generates a signal for aborting the processing of the wafer W.

[0098] The instruction unit M4 sends the signals generated in the processing unit M3 to various devices.

[0099] The hardware of the controller 10 can be constituted by, for example, one or more control computers. The controller 10 has, for example Figure 22The illustrated circuit 10A is configured as hardware. The circuit 10A may also be constituted by circuitry. Specifically, the circuit 10A includes a processor 10B, a memory 10C (storage unit), a storage device 10D (storage unit), a driver 10E, and an input / output port 10F. The processor 10B executes a program in cooperation with at least one of the memory 10C and the storage device 10D, and performs input / output of signals via the input / output port 10F, thereby constituting the above-described respective functional modules. The memory 10C and the storage device 10D function as a storage unit M2. The driver 10E is a circuit that drives various devices of the substrate processing system 1 respectively. The input / output port 10F performs input / output of signals between the driver 10E and various devices of the substrate processing system 1 (for example, a liquid processing unit U1, a heat processing unit U2, a holding stage 201, actuators 202, 203, cameras 310, 410, 510, light sources 322, 421, 522, etc.).

[0100] In the present embodiment, the substrate processing system 1 has one controller 10, but may also have a controller group (control unit) constituted by a plurality of controllers 10. When the substrate processing system 1 has a controller group, the above-described functional modules may be respectively implemented by one controller 10, or may be implemented by a combination of two or more controllers 10. When the controller 10 is constituted by a plurality of computers (circuit 10A), the above-described functional modules may be respectively implemented by one computer (circuit 10A), or may be implemented by a combination of two or more computers (circuit 10A). The controller 10 may also have a plurality of processors 10B. In this case, the above-described functional modules may be respectively implemented by one processor 10B, or may be implemented by a combination of two or more processors 10B.

[0101] [Function]

[0102] In the present embodiment, the mirror member 430 has a reflecting surface 432 that is inclined with respect to the rotation axis of the holding stage 201 and faces the peripheral regions Wd of the end face Wc and the back face Wb of the wafer W held on the holding stage 201. Further, in the present embodiment, the reflected light formed by reflecting the light from the peripheral region Wd of the front surface Wa of the wafer W held on the holding stage 201 and the light from the end face Wc of the wafer W held on the holding stage 201 by the reflecting surface 432 of the mirror member 430 is input to the imaging element 412 of the camera 410 via the lens 411. Therefore, both the peripheral region Wd of the front surface Wa of the wafer W and the end face Wc of the wafer W are simultaneously imaged by one camera 410. Thus, multiple cameras are not required, and as a result, the space for arranging multiple cameras is also not required. Further, a mechanism for moving the camera 410 is not required, and thus, the space for arranging this mechanism is also not required. In this way, in the present embodiment, the device structure of the inspection unit U3 is extremely simplified. As a result, equipment accidents can be suppressed, and miniaturization and cost reduction of the inspection unit U3 can be achieved.

[0103] In the present embodiment, the reflecting surface 432 is a curved surface that is recessed toward the side away from the end face Wc of the wafer W held on the holding stage 201. Therefore, the mirror image of the end face Wc of the wafer W reflected on the reflecting surface 432 is magnified compared to the real image. For example, when the reflecting surface 432 is not a curved surface, the width of the end face Wc of the wafer W in the captured image is about 20 pixels, but when the reflecting surface 432 is the above-described curved surface, the width of the end face Wc of the wafer W in the captured image is magnified about 1.5 times in the thickness direction of the wafer W. Thus, a more detailed captured image of the end face Wc of the wafer W can be obtained. As a result, by performing image processing on this captured image, the end face Wc of the wafer W can be inspected more accurately.

[0104] However, the optical path length from the light from the end face Wc of the wafer W being reflected by the reflecting surface 432 of the mirror member 430 and reaching the lens 411 is correspondingly longer by an amount corresponding to being reflected by the mirror member 430 compared to the optical path length of the light from the peripheral region Wd of the front surface Wa of the wafer W reaching the lens 411. However, in the present embodiment, a focus adjustment lens 427 is disposed in the middle of the optical path between the light from the end face Wc of the wafer W being reflected by the reflecting surface 432 of the mirror member 430 and reaching the lens 411. The focus adjustment lens 427 is configured to align the imaging position of the end face Wc of the wafer W with the imaging element 412. Therefore, since the imaging position of the end face Wc of the wafer W is aligned with the imaging element 412 by the focus adjustment lens 427, both the peripheral region Wd of the front surface Wa of the wafer W and the end face Wc of the wafer W in the captured image become clear. Thus, by performing image processing on this captured image, the end face Wc of the wafer W can be inspected more accurately.

[0105] In the present embodiment, the illumination module 420 irradiates diffused light onto the reflecting surface 432 of the mirror member 430 in such a manner that the reflected light formed by reflecting the diffused light from the illumination module 420 by the reflecting surface 432 of the mirror member 430 reaches the end surface Wc of the wafer W held on the holding stage 201. Therefore, the diffused light is incident on the end surface Wc of the wafer W from various directions. As a result, the end surface Wc of the wafer W is illuminated uniformly as a whole. Consequently, the end surface Wc of the wafer W can be imaged more clearly.

[0106] In the present embodiment, the light emitted from the light source 421 is scattered by the light scattering member 422, magnified by the cylindrical lens 425, and then diffused by the light diffusing member 426. Therefore, the diffused light is incident on the end surface Wc of the wafer W from various directions. As a result, the end surface Wc of the wafer W is illuminated uniformly as a whole. Consequently, the end surface Wc of the wafer W can be imaged more clearly.

[0107] [Other Embodiments]

[0108] As described above in detail, embodiments of the present invention have been described, and various modifications can be made to the above embodiments within the scope of the gist of the present invention. For example, it is sufficient that the reflecting surface 432 is inclined with respect to the rotation axis of the holding stage 201 and faces the peripheral region Wd of the end surface Wc and the back surface Wb of the wafer W held on the holding stage 201, and it may have a shape other than the curved surface (for example, a flat surface).

[0109] The peripheral imaging sub-unit 400 may not include the focus adjustment lens 427.

[0110] The peripheral imaging sub-unit 400 may not include any one of the light scattering member 422, the cylindrical lens 425, and the light diffusing member 426.

[0111] The inspection unit U3 may also be disposed in the shelf units U10, U11. For example, the inspection unit U3 may be provided in a chamber positioned corresponding to the unit processing modules 14 to 17 in the shelf units U10, U11. In this case, the wafer W is directly transferred to the inspection unit U3 during the conveyance by the arms A1 to A8.

Claims

1. A substrate photographing apparatus, which comprises: a rotation holding part configured to hold a substrate and rotate the substrate; a mirror member having a reflection surface that is inclined with respect to the rotation axis of the rotation holding part and faces the peripheral regions of the end face and the back face of the substrate held by the rotation holding part; a first camera having an imaging element, and first light from the surface of the substrate held by the rotation holding part and reflected light formed by reflecting second light from the end face of the substrate held by the rotation holding part by the reflection surface of the mirror member are both input to the imaging element via a lens; a first light source disposed at a position above the surface of the substrate held by the rotation holding part; and a first semi-transparent mirror disposed between the first light source and the surface of the substrate, the first semi-transparent mirror being configured to transmit light from the first light source and reflect the first light and the reflected light, wherein the first camera and the first semi-transparent mirror are arranged and disposed along a horizontal direction, the substrate photographing apparatus further includes a focus adjustment lens configured to align the imaging position of the end face of the substrate with the imaging element, the focus adjustment lens is disposed midway in the optical path between the reflection surface of the mirror member where the second light is reflected by the reflection surface of the mirror member and the lens, such that the first light does not pass through the focus adjustment lens and the reflected light passes through the focus adjustment lens.

2. The substrate photographing apparatus according to claim 1, wherein the first light is light from the peripheral region of the surface of the substrate.

3. The substrate photographing apparatus according to claim 1, wherein the focus adjustment lens is disposed in the optical path hole in a manner that blocks a part of the optical path hole, and the optical path hole includes the optical paths of the first light and the reflected light reaching the lens.

4. The substrate photographing apparatus according to claim 1, wherein the focus adjustment lens is a double focus lens having two parts with different refractive powers.

5. The substrate photographing apparatus according to claim 1 or 2, wherein the reflection surface is a curved surface that is recessed toward the side away from the end face of the substrate held by the rotation holding part.

6. The substrate photographing apparatus according to claim 5, wherein the radius of curvature of the reflection surface is 10 mm to 30 mm.

7. The substrate photographing apparatus according to claim 1 or 2, wherein the substrate photographing apparatus further includes a second camera having an imaging element, and third light from the back face of the substrate held by the rotation holding part is input to the imaging element via a lens.

8. The substrate photographing apparatus according to claim 7, further comprises: a second light source disposed at a position below the back face of the substrate held by the rotation holding part; and a second semi-transparent mirror disposed between the second light source and the back face of the substrate, the second semi-transparent mirror being configured to transmit light from the second light source and reflect the third light, Among them, the second camera and the second semi-transparent mirror are arranged horizontally.

9. The substrate photographing device according to claim 1 or 2, wherein, the substrate photographing device further includes a third camera having a photographing element, and fourth light from the surface of the substrate held by the rotary holding portion is input to the photographing element via a lens.

10. The substrate photographing device according to claim 8, wherein, the first camera is configured to photograph a photographing range that does not overlap with the irradiation range from the second light source when viewed from above.

11. The substrate photographing device according to claim 9, further including: a third light source disposed at a position above the surface of the substrate held by the rotary holding portion; and a third semi-transparent mirror disposed between the third light source and the surface of the substrate, the third semi-transparent mirror being configured to transmit light from the third light source and reflect the fourth light, wherein the third camera and the third semi-transparent mirror are arranged horizontally.

12. The substrate photographing device according to claim 9, wherein, the substrate photographing device further includes a driving portion configured to move the substrate held by the rotary holding portion horizontally, the third camera is configured to photograph the surface of the substrate being moved by the driving portion.

13. The substrate photographing device according to claim 9, further including: a third light source disposed at a position above the surface of the substrate held by the rotary holding portion; a third semi-transparent mirror disposed between the third light source and the surface of the substrate, the third semi-transparent mirror being configured to transmit light from the third light source and reflect the fourth light; and a driving portion configured to move the substrate held by the rotary holding portion horizontally, the third camera is configured to photograph the surface of the substrate being moved by the driving portion, when viewed from above, the third semi-transparent mirror extends in a crossing direction that crosses the moving direction of the substrate moved by the driving portion, the length of the third semi-transparent mirror in the crossing direction is greater than the diameter of the substrate.

14. The substrate photographing device according to claim 12, wherein, the substrate photographing device further includes a housing that houses the mirror member and the driving portion, an input / output port for inputting / outputting the substrate is formed in the housing, the mirror member is disposed at a position inside the housing with respect to the input / output port as a reference, the driving portion is configured to move the substrate held by the rotary holding portion between the vicinity of the input / output port and the vicinity of the mirror member.

Images