Substrate processing apparatus and substrate processing method

Abstract

To accurately acquire the state of the object being processed. [Solution] A substrate processing apparatus is provided, comprising: a processing container that processes an object to be processed by supplying a processing gas while heating the object to be processed; a mounting table provided inside the processing container and having a plurality of recesses on its upper surface for placing the object to be processed; a hole formed in the mounting table for passing a pin that moves the object to be processed up and down when loading and unloading the object to be processed; a rotation mechanism that rotates the mounting table so that the object to be processed passes through a plurality of processing areas; an imaging unit that captures an image including polarization information of the object to be processed placed in the recesses from above the mounting table; and a measuring unit that measures a physical quantity indicating the state of the object to be processed based on the polarization information contained in the image.

Description

Technical Field

[0001] The present disclosure relates to a substrate processing apparatus and a substrate processing method.

Background Art

[0002] Techniques for determining the state of a substrate placed on a mounting table of a substrate processing apparatus are known. For example, in Patent Document 1, a substrate state determination apparatus is disclosed that uses a substrate state determination model that takes an image of a substrate placed on a mounting table as an input and outputs a value related to the state of the substrate corresponding to the image of the substrate to determine the state of the substrate corresponding to the image of the substrate.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The present disclosure provides a technique for accurately obtaining the state of a processing object.

Means for Solving the Problems

[0005] According to one aspect of the present disclosure, there is provided a substrate processing apparatus including: a processing container that supplies and processes a processing gas while heating a processing object; a mounting table provided in the processing container and having a plurality of recesses on an upper surface for mounting the processing object; a hole formed in the mounting table through which a pin that moves the processing object up and down when the processing object is carried in and out passes; a rotation mechanism that rotates the mounting table so that the processing object passes through a plurality of processing regions; an imaging unit that images, from above the mounting table, an image including polarization information of the processing object placed in the recess; and a measurement unit that measures a physical quantity indicating the state of the processing object based on the polarization information included in the image.

Effects of the Invention

[0006] One aspect of this is that it allows for accurate acquisition of the state of the object being processed. [Brief explanation of the drawing]

[0007] [Figure 1] This is a cross-sectional view showing an example of a substrate processing apparatus. [Figure 2] This is a top view showing an example of a chamber. [Figure 3] This is a perspective view showing an example of a substrate processing apparatus. [Figure 4] This is a plan view showing an example of the configuration inside the chamber. [Figure 5] This is a cross-sectional view of the chamber along the concentric circles of the susceptor. [Figure 6] This is a cross-sectional view showing the region where the first ceiling surface of the substrate processing apparatus is provided. [Figure 7] A block diagram showing an example of a computer hardware configuration. [Figure 8] This is a block diagram showing an example of the functional configuration of a state determination device. [Figure 9] This figure shows the first example of a polarized image. [Figure 10] This is a diagram to explain how to calculate the amount of warping. [Figure 11] This figure shows a second example of a polarized image. [Figure 12] This flowchart shows an example of a substrate processing method. [Figure 13] This figure shows an example of measurement accuracy. [Figure 14] This figure shows an example of measurement error. [Modes for carrying out the invention]

[0008] The following describes embodiments for implementing this disclosure with reference to the drawings. In each drawing, the same reference numerals are used for identical components, and redundant explanations may be omitted.

[0009] [Embodiment] One embodiment of the present disclosure is an example of a substrate processing apparatus for processing a substrate, which is an example of an object to be processed. In this embodiment, the substrate processing apparatus heat-treats a semiconductor wafer, which is an example of a substrate, in a processing container. The substrate processing apparatus is provided with a state determination device for determining the state of the semiconductor wafer placed in the processing container.

[0010] In this embodiment, the substrate processing apparatus is provided with a mounting platform called a susceptor inside a processing container. The substrate processing apparatus places a semiconductor wafer in a plurality of recesses formed on the surface of the susceptor and performs various substrate processing on the semiconductor wafer placed in the recesses while rotating the susceptor inside the processing container.

[0011] When a semiconductor wafer is placed in the recess of a susceptor after being brought into the processing container, the semiconductor wafer may warp due to the temperature difference between the semiconductor wafer and the surface of the susceptor. If the semiconductor wafer is warped, the semiconductor may detach from the recess during substrate processing. Therefore, in order to perform substrate processing stably, a technology has been proposed to detect the warping of the semiconductor wafer placed on the susceptor.

[0012] Conventional techniques involve imaging a susceptor on which a semiconductor wafer is placed from the side and determining the warping of the semiconductor wafer based on the region of the semiconductor wafer imaged above the surface of the susceptor. However, while conventional techniques can determine whether or not warping is occurring in the semiconductor wafer, they cannot measure a quantitative value of the warping (hereinafter referred to as "warping amount"). If the warping amount of the semiconductor wafer placed on the susceptor can be measured, it will be possible to control the detachment of the semiconductor wafer during substrate processing with high precision.

[0013] In addition, the recess of the susceptor is formed larger than the size of the semiconductor wafer in order to provide a certain clearance between the semiconductor wafer and the side wall of the recess. Since the susceptor rotates during substrate processing, the position of the semiconductor wafer in the recess may shift due to centrifugal force. As a result, the semiconductor wafer and the side wall of the recess come into contact, which is one of the causes of particle generation on the semiconductor wafer. If the distance between the end of the semiconductor wafer placed on the susceptor and the outer periphery of the recess (hereinafter referred to as "clearance amount") can be measured, the generation of particles caused by the contact between the semiconductor wafer and the side wall of the recess can be suppressed.

[0014] This embodiment aims to accurately acquire the state of the object to be processed. For this purpose, in this embodiment, an image including the polarization information of the object to be processed placed in the recess formed on the surface of the mounting table is captured from above the mounting table, and a physical quantity indicating the state of the object to be processed is measured based on the polarization information included in the image. As an example, the physical quantity indicating the state of the object to be processed may be the amount of warping of the object to be processed or the clearance amount of the object to be processed.

[0015] On one side, according to this embodiment, since the physical quantity indicating the state of the object to be processed is measured based on the polarization information, the state of the object to be processed can be accurately acquired. On the other side, according to this embodiment, since the process can be executed when the object to be processed is in a state suitable for processing, the object to be processed can be stably processed.

[0016] <Substrate processing apparatus> A configuration example of the substrate processing apparatus of this embodiment will be described. FIG. 1 is a schematic cross-sectional view showing an example of the substrate processing apparatus.

[0017] As shown in FIG. 1, the substrate processing apparatus 180 includes a chamber 1, a susceptor 2, a rotating shaft 22, a recess 24, a control unit 100, a window 110, a state determination device 170, and the like. In addition, the substrate processing apparatus 180 may include various components in the chamber 1 necessary for substrate processing and various components attached to the chamber 1 as needed.

[0018] Chamber 1 is a processing container for processing substrates such as semiconductor wafers W. Chamber 1 is a flattened container that is approximately circular when viewed from above. Chamber 1 can be any substrate processing chamber, and the content of the substrate processing that can be performed inside Chamber 1 is not limited. Therefore, the substrate processing apparatus 180 can be configured as an apparatus for performing various substrate processing. In this embodiment, an example in which Chamber 1 is configured as a film deposition chamber for film deposition processing will be described.

[0019] Chamber 1 is configured as a sealed container for processing semiconductor wafers W. Chamber 1 has a top plate 11 and a container body 12. The top plate 11 is separable from the container body 12. Due to the reduced pressure inside, the top plate 11 is pressed against the container body 12 via a sealing member 13 such as an O-ring, thereby sealing Chamber 1 airtight. On the other hand, the top plate 11 is separated from the container body 12 by lifting it upward using a drive mechanism.

[0020] Chamber 1 has a hole 16 in a part of the top plate 11 so that the camera 140 of the state determination device 170 can image the inside of Chamber 1. The hole 16 is an opening that leads to the inside of Chamber 1, and by positioning the window 110 to close the hole 16, Chamber 1 becomes sealed.

[0021] The window 110 is provided above the hole 16, closing the opening created by the hole 16 and ensuring an imaging field of view that can be viewed from above by the camera 140 installed above. The window 110 may be made of various light-transmitting materials, but for example, it may be made as a quartz window 110 made of quartz glass.

[0022] Figure 2 is a top view showing an example of a chamber. As shown in Figure 2, the top surface of the chamber 1 is made up of a top plate 11, and a hole 16 is formed in a part of the top plate 11. A window 110, which is slightly larger than the hole 16, is provided to cover the hole 16, and the hole 16 is sealed by an O-ring 115.

[0023] Let's return to Figure 1 for explanation. When performing film deposition using Chamber 1, it is common practice to heat Chamber 1 to a high temperature and supply the reaction gas for film deposition into Chamber 1. In the substrate processing apparatus 180, we will explain using an example of film deposition using atomic layer deposition, which forms an atomic layer on the surface of the semiconductor wafer W, or molecular layer deposition, which forms a molecular layer.

[0024] A susceptor 2 is provided inside the chamber 1, with a center of rotation at the center of the chamber 1. The susceptor 2 is a disc-shaped mounting platform on which a substrate is placed. Multiple recesses 24 are formed on the surface of the susceptor 2 along the circumferential direction. The recesses 24 are approximately the same size as the semiconductor wafer W, and the semiconductor wafer W is placed on the recesses 24. The depth of the recesses 24 may be the same as the thickness of the semiconductor wafer W, or it may be deeper than the thickness of the semiconductor wafer W. In the example in Figure 1, the case where the thickness of the semiconductor wafer W and the depth of the recesses 24 are approximately the same is shown.

[0025] The susceptor 2 is fixed in the center to a cylindrical core 21. The core 21 is fixed to the upper end of a vertically extending rotating shaft 22. The rotating shaft 22 passes through the bottom 14 of the container body 12, and its lower end is attached to a drive unit 23. The drive unit 23 rotates the rotating shaft 22 around its vertical axis. The rotating shaft 22 and the drive unit 23 are housed in a cylindrical case body 20 with an open top. The case body 20 is airtightly attached to the lower surface of the bottom 14 of the chamber 1 via a flange portion 20a provided on its top surface. As a result, the inside of the case body 20 is isolated from the external atmosphere.

[0026] Figure 3 is a perspective view showing an example of a substrate processing apparatus. Figure 4 is a plan view showing an example of the configuration inside the chamber. Figures 3 and 4 are diagrams illustrating the structure inside chamber 1, and for the sake of clarity, the top plate 11 is not shown.

[0027] As shown in Figures 3 and 4, the surface of the susceptor 2 is provided with circular recesses 24 for placing multiple (five in the illustrated example) semiconductor wafers W along the rotational direction (circumferential direction). For convenience, only one semiconductor wafer W is shown in Figure 3. The recesses 24 have an inner diameter that is slightly larger than the diameter of the semiconductor wafer W, for example, 4 mm, and a depth that is approximately equal to the thickness of the semiconductor wafer W. Therefore, when the semiconductor wafer W is placed in the recesses 24, the surface of the semiconductor wafer W and the surface of the susceptor 2 (the area where the semiconductor wafer W is not placed) are at the same height. Through holes are formed in the bottom surface of the recesses 24, through which, for example, three lifting pins pass to support the back surface of the semiconductor wafer W and raise and lower the semiconductor wafer W.

[0028] Above the susceptor 2, reaction gas nozzles 31, 32 and separation gas nozzles 41, 42, each made of quartz, are arranged at intervals from one another in the circumferential direction of the chamber 1 (the direction of rotation of the susceptor 2 (arrow A in Figure 3)). In the illustrated example, the separation gas nozzle 41, reaction gas nozzle 31, separation gas nozzle 42, and reaction gas nozzle 32 are arranged in this order clockwise from the transport port 15 (the direction of rotation of the susceptor 2). The gas introduction ports 31a, 32a, 41a, and 42a, which are the base ends of the reaction gas nozzles 31, 32 and separation gas nozzles 41, 42, are fixed to the outer circumferential surface of the container body 12. As a result, the gas is introduced into the chamber 1 from the outer circumferential surface of the chamber 1 and is mounted to extend horizontally to the susceptor 2 along the radial direction of the container body 12.

[0029] The reaction gas nozzle 31 is connected to the supply source of the first reaction gas via piping and a flow controller, etc. The reaction gas nozzle 32 is connected to the supply source of the second reaction gas via piping and a flow controller, etc. The separation gas nozzles 41 and 42 are connected to the supply source of the separation gas via piping and a flow control valve, etc. As the first reaction gas, a film-forming gas such as a Si-containing gas can be used, and as the second reaction gas, a gas such as an oxidizing gas or nitriding gas, or a film-forming gas similar to the first reaction gas can be used. As the separation gas, noble gases such as helium (He) and argon (Ar), or inert gases such as nitrogen (N2) gas can be used.

[0030] The reaction gas nozzles 31 and 32 have discharge holes 33 (see Figure 4) arranged along their length at intervals of, for example, 10 mm. The region below reaction gas nozzle 31 becomes a first processing region P1 for adsorbing the first reaction gas onto the semiconductor wafer W. The region below reaction gas nozzle 32 becomes a second processing region P2 where a second reaction gas is supplied to react with the first reaction gas adsorbed onto the semiconductor wafer W in the first processing region P1, and the first and second reaction gases deposit reaction products.

[0031] As the semiconductor wafer W rotates and sequentially passes through a first processing area P1 supplied with a first reaction gas and a second processing area P2 supplied with a second reaction gas, the first reaction gas is adsorbed onto the surface of the semiconductor wafer W, and reaction products resulting from the reaction between the first and second reaction gases are sequentially deposited. As a result, atomic or molecular layers of reaction products are formed on the surface of the semiconductor wafer W.

[0032] As shown in Figures 3 and 4, two convex portions 4 are provided inside the chamber 1. The convex portions 4, together with the separation gas nozzles 41 and 42, constitute the separation region D, and are therefore attached to the underside of the top plate 11 so as to protrude toward the susceptor 2, as will be described later. When viewed from above, the convex portions 4 have a fan shape with their tops cut in an arc shape, with the inner arc connecting to the protruding portion 5 and the outer arc positioned along the inner circumferential surface of the container body 12 of the chamber 1.

[0033] Figure 5 is a cross-sectional view of the chamber 1 along the concentric circles of the susceptor 2 of the substrate processing apparatus 180. Figure 5 shows a cross-section of the chamber 1 along the concentric circles of the susceptor 2 from reaction gas nozzle 31 to reaction gas nozzle 32 of the substrate processing apparatus 180. As shown in Figure 5, a convex portion 4 is attached to the back surface of the top plate 11. Therefore, inside the chamber 1, there is a flat, low first ceiling surface 44 which is the lower surface of the convex portion 4, and second ceiling surfaces 45 which are located on both sides of the first ceiling surface 44 in the circumferential direction and are higher than the first ceiling surface 44. When viewed from above, the first ceiling surface 44 has a fan shape with its top cut in an arc shape. In addition, a groove portion 43 is formed in the center of the circumferential direction and extends radially. A separation gas nozzle 42 is housed in the groove portion 43. Similarly, a groove portion 43 is formed in the other convex portion 4, and a separation gas nozzle 41 is housed in the groove portion 43. The separation gas nozzles 41 and 42 have multiple gas discharge holes 42h arranged at intervals of, for example, 10 mm along the length of the separation gas nozzles 41 and 42, opening toward the susceptor 2. Additionally, reaction gas nozzles 31 and 32 are provided in the space below the second ceiling surface 45. The reaction gas nozzles 31 and 32 are spaced apart from the second ceiling surface 45 and located near the semiconductor wafer W.

[0034] The first ceiling surface 44 forms a narrow separation space H relative to the susceptor 2. When N2 gas is supplied from the discharge hole 42h of the separation gas nozzle 42, the N2 gas flows through the separation space H toward the spaces 481 and 482 below the second ceiling surface 45 where the reaction gas nozzles 31 and 32 are located. At this time, the volume of the separation space H is smaller than the volume of spaces 481 and 482. Therefore, the pressure in the separation space H can be made higher than the pressure in spaces 481 and 482 by the N2 gas. That is, a high-pressure separation space H is formed between spaces 481 and 482. In addition, the N2 gas flowing out of the separation space H into spaces 481 and 482 acts as a counterflow for the first reaction gas from the first processing area P1 and the second reaction gas from the second processing area P2. Thus, the first reaction gas from the first processing area P1 and the second reaction gas from the second processing area P2 are separated by the separation space H. Therefore, mixing and reaction between the first reaction gas and the second reaction gas within chamber 1 is suppressed.

[0035] The height h1 of the first ceiling surface 44 relative to the upper surface of the susceptor 2 is set to a height suitable for making the pressure in the separation space H higher than the pressure in spaces 481 and 482, taking into consideration the pressure inside the chamber 1 during the film deposition process, the rotation speed of the susceptor 2, the flow rate of the separation gas, etc.

[0036] On the other hand, the lower surface of the top plate 11 is provided with a projection 5 (see Figures 3 and 4) that surrounds the outer circumference of the core portion 21 that fixes the susceptor 2. The projection 5 is continuous with the part of the convex portion 4 on the side of the center of rotation, and its lower surface is formed at the same height as the first ceiling surface 44. Figure 1, which was referred to earlier, shows the area where the second ceiling surface 45 is provided.

[0037] Figure 6 is a cross-sectional view showing the region where the first ceiling surface 44 of the substrate processing apparatus 180 is provided. As shown in Figure 6, a bent portion 46 is formed on the outer edge of the fan-shaped convex portion 4, bending in an L-shape to face the outer end surface of the susceptor 2. Similar to the convex portion 4, the bent portion 46 suppresses the intrusion of reaction gases from both sides of the separation region D, thereby suppressing the mixing of the first reaction gas and the second reaction gas. The fan-shaped convex portion 4 is provided on the top plate 11, and since the top plate 11 can be removed from the container body 12, there is a small gap between the outer circumferential surface of the bent portion 46 and the container body 12. The gap between the inner circumferential surface of the bent portion 46 and the outer end surface of the susceptor 2, and the gap between the outer circumferential surface of the bent portion 46 and the container body 12 are set to dimensions similar to, for example, the height of the first ceiling surface 44 relative to the top surface of the susceptor 2.

[0038] In the separation region D, the inner circumferential surface of the container body 12 is formed as a vertical surface close to the outer circumferential surface of the bent portion 46, as shown in Figure 5. On the other hand, in areas other than the separation region D, the inner circumferential surface of the container body 12 is recessed outward from the part facing the outer end surface of the susceptor 2 to the bottom 14, as shown in Figure 1, forming an exhaust region. Specifically, the exhaust region communicating with the first processing region P1 is called the first exhaust region E1, and the region communicating with the second processing region P2 is called the second exhaust region E2. At the bottom of the first exhaust region E1 and the second exhaust region E2, a first exhaust port 61 and a second exhaust port 62 are formed, respectively, as shown in Figure 1. The first exhaust port 61 and the second exhaust port 62 are connected to an exhaust device 64 such as a vacuum pump via exhaust piping 63, as shown in Figure 1. A pressure controller 65 is provided in the exhaust piping 63.

[0039] A heater unit 7 is provided in the space between the susceptor 2 and the bottom 14 of the chamber 1, as shown in Figures 1 and 6, and the semiconductor wafer W on the susceptor 2 is heated to a temperature (e.g., 400°C) determined by the process recipe via the susceptor 2. An annular cover member 71 is provided on the lower side near the periphery of the susceptor 2. The cover member 71 separates the atmosphere from the space above the susceptor 2 to the first exhaust region E1 and the second exhaust region E2 from the atmosphere in which the heater unit 7 is located, and suppresses the intrusion of gas into the lower region of the susceptor 2. The cover member 71 has an inner member 71a provided so as to face the outer edge of the susceptor 2 and the outer circumference side from below, and an outer member 71b provided between the inner member 71a and the inner circumferential surface of the chamber 1. The inner member 71a surrounds the heater unit 7 all around, below the outer edge of the susceptor 2 (and slightly below the outer edge). The outer member 71b is provided in the separation region D below the bent portion 46 formed on the outer edge of the convex portion 4, and in close proximity to the bent portion 46.

[0040] The bottom portion 14 on the side of the rotation center relative to the space where the heater unit 7 is located protrudes upward to form a projection 12a, approaching the core portion 21 near the center of the lower surface of the susceptor 2. There is a narrow space between the projection 12a and the core portion 21, and the gap between the inner circumferential surface of the through hole for the rotating shaft 22 that penetrates the bottom portion 14 and the rotating shaft 22 is also narrow. These narrow spaces are in communication with the case body 20. The case body 20 is provided with a purge gas supply pipe 72 for supplying N2 gas, which is a purge gas, into these narrow spaces for purging. In addition, the bottom portion 14 of the chamber 1 is provided with a plurality of purge gas supply pipes 73 at predetermined angular intervals in the circumferential direction below the heater unit 7 for purging the space where the heater unit 7 is located. Furthermore, a cover member 7a is provided between the heater unit 7 and the susceptor 2 to prevent gas from entering the area where the heater unit 7 is installed. This cover member 7a covers the area from the inner circumferential surface of the outer member 71b (the upper surface of the inner member 71a) to the upper end of the protrusion 12a in the circumferential direction. The cover member 7a is made of, for example, quartz.

[0041] A separation gas supply pipe 51 is connected to the center of the top plate 11 of chamber 1 and is configured to supply N2 gas, which is the separation gas, to the space 52 between the top plate 11 and the core 21. The separation gas supplied to space 52 is discharged towards the periphery along the side surface of the mounting area of ​​the susceptor 2 through a narrow gap 50 between the protrusion 5 and the susceptor 2. The gap 50 can be maintained at a higher pressure than spaces 481,482 by the separation gas. Thus, the gap 50 prevents the first reaction gas supplied to the first processing area P1 and the second reaction gas supplied to the second processing area P2 from mixing through the central area C. In other words, the gap 50 (or central area C) functions similarly to the separation space H (or separation area D).

[0042] As shown in Figures 3 and 4, a transfer port 15 is formed in the side wall of the chamber 1 for transferring the semiconductor wafer W between the external transfer arm 10 and the susceptor 2. The transfer port 15 is opened and closed by a gate valve. The recess 24, which is the mounting area of ​​the susceptor 2, is located opposite the transfer port 15, and the semiconductor wafer W is transferred between it and the transfer arm 10 at this position. For this reason, a lifting pin and its lifting mechanism are provided on the lower side of the susceptor 2 at a location corresponding to the transfer position, allowing the transfer to pass through the recess 24 and lift the semiconductor wafer W from the back side.

[0043] The control unit 100 controls the operation of each part of the substrate processing apparatus 180. The control unit 100 may be, for example, a computer. The computer program that controls the operation of each part of the substrate processing apparatus 180 is stored on the medium 102, read into the storage unit 101 by a predetermined reading device, and installed in the control unit 100. The medium 102 may be, for example, a hard disk, compact disk, magneto-optical disk, memory card, flexible disk, etc.

[0044] <Status determination device> Returning to Figure 1, the state determination device 170 will be described. As shown in Figure 1, the state determination device 170 includes lighting 120, lighting reflector 125, polarizing lighting 130, camera 140, housing 150, and processing unit 160, etc.

[0045] The illumination 120 is a light source that emits light, and it emits light upwards toward the illumination reflector 125 located above the illumination 120. The reflected light reflected by the illumination reflector 125 enters the window 110. Various light sources can be used for illumination 120 as long as they can emit light at an appropriate brightness. For example, illumination 120 may use a light-emitting diode (LED). In addition, illumination 120 may be installed near the wall surface of the housing 150 and emit light diagonally upwards so as not to obstruct the imaging field of view of the camera 140.

[0046] The illumination reflector 125 reflects light incident from the illumination 120 and illuminates the window 110 with the reflected light. By illuminating the window 110 with the reflected light from the illumination reflector 125, the inside of the chamber 1 can be brightened. The illumination reflector 125 has a reflective surface 126 on its lower surface in order to reflect light incident from below. The illumination reflector 125 has an opening so as not to obstruct the imaging field of view of the camera 140.

[0047] Polarized illumination 130 is an example of an illumination unit having a light source that emits polarized light. Polarized light is light that has been polarized in a predetermined direction. Polarized illumination 130 may also include a polarizing plate that polarizes the light emitted by the light source.

[0048] The polarized light illuminator 130 is positioned above the window 110 and emits polarized light downwards. The polarized light emitted by the polarized light illuminator 130 enters the window 110. Therefore, the polarized light illuminator 130 emits polarized light through the window 110 onto the surface of the susceptor 2 or the surface of the semiconductor wafer W placed on the susceptor 2.

[0049] The polarizing light 130 has a slit plate with slits of a predetermined shape. The slit plate shapes the polarized light irradiated by the polarizing light 130 into a predetermined shape. The shape of the slits can be any shape, such as a circle, rectangle, or polygon. In this embodiment, it is rectangular. As a result, the polarizing light 130 can irradiate the surface of the semiconductor wafer W placed on the susceptor 2 with a marker of a predetermined shape.

[0050] The polarized light illuminator 130 may have a slit plate with multiple slits formed therein. The multiple slits may be the same shape or may be different shapes. This allows the polarized light illuminator 130 to illuminate multiple markers on the surface of the susceptor 2 or the surface of the semiconductor wafer W placed on the susceptor 2. Since the multiple markers share a light source, they become markers polarized in the same direction.

[0051] The polarized light 130 may be installed near the wall surface of the housing 150 so as not to obstruct the imaging field of view of the camera 140, and may emit polarized light diagonally downwards. The illumination reflector 125 has an opening so as not to obstruct the polarized light emitted by the polarized light 130. In Figure 1, two polarized lights 130 are provided, but the number of polarized lights 130 is not limited, and one polarized light 130 may be used.

[0052] Camera 140 is an imaging unit that images the inside of chamber 1 through window 110. Camera 140 may also be a polarizing camera capable of capturing images containing polarization information. Camera 140 may also be a camera that can switch between a polarization mode, which captures images containing polarization information, and a normal mode, which captures images without polarization information. Hereinafter, images containing polarization information will be referred to as "polarized images".

[0053] In this embodiment, the camera 140 captures an image that includes the degree of polarization (DoP) as polarization information. The degree of polarization is information that indicates the degree of polarization relative to the brightness level. Since the degree of polarization differs depending on the material, the material of the subject can be determined based on the degree of polarization of each pixel in the image. In this embodiment, based on the image including the degree of polarization, it is possible to distinguish between the region in which the susceptor 2 is imaged and the region in which the semiconductor wafer W is imaged.

[0054] Camera 140 can capture images with noise or disturbances removed by cutting out unpolarized light when capturing polarized images. Furthermore, because polarized images can be captured with a short shutter speed, clear images can be captured even when the susceptor 2 is rotating at high speed.

[0055] The housing 150 is a casing for housing the window 110, lighting 120, lighting reflector 125, polarizing light 130, and camera 140. By covering the entire unit with the housing 150, the area around the camera 140 can be darkened, creating conditions suitable for imaging.

[0056] The processing unit 160 performs calculations to acquire the state of the substrate based on the image captured by the camera 140. The processing unit 160 may be, for example, a computer. The processing unit 160 is configured to perform calculations and may be configured as, for example, a microcomputer equipped with a central processing unit (CPU) and operating by program, or as an integrated circuit such as an ASIC (Application Specific Integrated Circuit) designed and manufactured for a specific application.

[0057] In this embodiment, the control unit 100 and the processing unit 160 are shown with different configurations, but the control unit 100 and the processing unit 160 may be integrated into the same processing unit. For example, the control unit 100 may include the functions of the processing unit 160.

[0058] <Computer> The control unit 100 and processing unit 160 shown in Figure 1 are implemented by a computer with a hardware configuration such as that shown in Figure 7. Figure 7 is a block diagram showing an example of a computer hardware configuration.

[0059] As shown in Figure 7, the computer 500 is equipped with an input device 501, an output device 502, an external interface 503, RAM (Random Access Memory) 504, ROM (Read Only Memory) 505, a CPU (Central Processing Unit) 506, a communication interface 507, and an HDD (Hard Disk Drive) 508, all of which are interconnected via bus B. The input device 501 and output device 502 may be connected and used only when necessary.

[0060] The input device 501 is a keyboard, mouse, touch panel, etc., used by operators to input various operation signals. The output device 502 is a display, etc., which displays the processing results from the computer 500. The communication I / F 507 is an interface that connects the computer 500 to a network. The HDD 508 is an example of a non-volatile storage device that stores programs and data.

[0061] External I / F 503 is an interface to external devices. Computer 500 can read from and / or write to recording media 503a such as an SD (Secure Digital) memory card via External I / F 503. ROM 505 is an example of a non-volatile semiconductor memory (storage device) that stores programs and data. RAM 504 is an example of a volatile semiconductor memory (storage device) that temporarily holds programs and data.

[0062] The CPU 506 is a processing unit that reads programs and data from storage devices such as the ROM 505 and HDD 508 onto the RAM 504 and executes processing, thereby realizing the overall control and functions of the computer 500.

[0063] <Functional Configuration> The functional configuration of the processing unit 160 of the state determination device 170 will be explained with reference to Figure 8. Figure 8 is a block diagram showing an example of the functional configuration of the state determination device.

[0064] As shown in Figure 8, the processing unit 160 of the state determination device 170 comprises an imaging control unit 610, a measurement unit 620, and a determination unit 630. The processing unit 160 functions as the imaging control unit 610, the measurement unit 620, and the determination unit 630 when a pre-installed state determination program is executed.

[0065] For example, the imaging control unit 610, the measurement unit 620, and the determination unit 630 are realized by the CPU 506 shown in Figure 7 executing a state determination program loaded onto the RAM 504.

[0066] The imaging control unit 610 controls the camera 140 to capture a polarized image. The imaging control unit 610 acquires the polarized image captured by the camera 140. Specifically, the imaging control unit 610 sets the camera 140 to polarization mode and sends a control signal to the camera 140 to instruct it to capture an image. Since the imaging field of view of the camera 140 includes the window 110, the camera 140 can capture a polarized image inside the chamber 1 through the window 110. The camera 140 outputs image data showing the polarized image generated by the capture to the processing unit 160. The imaging control unit 610 acquires the polarized image based on the image data input to the processing unit 160.

[0067] The imaging control unit 610 may control the timing of the polarization image acquisition. The imaging control unit 610 may acquire the polarization image after a predetermined waiting time has elapsed since the semiconductor wafer W was loaded into the chamber 1. The waiting time may be the time at which the warp of the semiconductor wafer W is at its maximum. The waiting time can be determined empirically by measuring the time at which the warp of the semiconductor wafer W is at its maximum.

[0068] The imaging control unit 610 may capture polarization images at predetermined time intervals after the waiting time has elapsed. The time intervals may be arbitrarily determined. The imaging control unit 610 may repeatedly capture polarization images until the amount of warping of the semiconductor wafer W falls below a threshold, or until the elapsed time since the semiconductor wafer W was loaded into the chamber 1 exceeds a specified time.

[0069] The measurement unit 620 measures a physical quantity that indicates the state of the semiconductor wafer W. The measurement unit 620 may also measure the physical quantity that indicates the state of the semiconductor wafer W based on polarization information contained in the image captured by the camera 140.

[0070] The measurement unit 620 may measure the amount of warpage of the semiconductor wafer W. The measurement unit 620 may measure the amount of warpage of the semiconductor wafer W based on the position of a marker included in the polarization image. The measurement unit 620 may measure the amount of warpage of the semiconductor wafer W based on the distance between the position of a marker included in the polarization image and a specified position. The specified position may be the position of a marker when no warpage occurs in the semiconductor wafer W. The specified position may be the position of a marker included in the polarization image taken immediately after the semiconductor wafer W is loaded into the chamber 1. Alternatively, the specified position may be the position of a marker included in the polarization image taken of the semiconductor wafer W in the chamber 1 when the temperature inside the chamber 1 is at room temperature.

[0071] The measuring unit 620 may measure the clearance amount of the semiconductor wafer W. The measuring unit 620 may detect the edge of the semiconductor wafer W based on the polarization information contained in the polarization image and measure the clearance amount of the semiconductor wafer W based on the distance between the edge of the semiconductor wafer W and the outer circumference of the recess 24 of the susceptor 2. The position of the outer circumference of the recess 24 of the susceptor 2 can be predetermined.

[0072] The determination unit 630 determines the state of the semiconductor wafer W. The determination unit 630 may also determine whether the semiconductor wafer W is in a state suitable for substrate processing. The determination unit 630 may also determine the state of the semiconductor wafer W based on physical quantities measured by the measurement unit 620.

[0073] The determination unit 630 may determine the state of the semiconductor wafer W based on the amount of warping of the semiconductor wafer W. The determination unit 630 may determine that the semiconductor wafer W is in a state suitable for substrate processing if the amount of warping of the semiconductor wafer W is below a predetermined threshold. The determination unit 630 may perform the determination based on the amount of warping of the semiconductor wafer W after the semiconductor wafer W has been loaded into the chamber 1 and before the process is executed (in other words, while the susceptor 2 is not rotating).

[0074] The determination unit 630 may determine the state of the semiconductor wafer W based on the clearance amount of the semiconductor wafer W. The determination unit 630 may determine that the semiconductor wafer W is in a state suitable for substrate processing if the clearance amount of the semiconductor wafer W is greater than or equal to a predetermined threshold. The determination unit 630 may perform the determination based on the clearance amount of the semiconductor wafer W while the process on the semiconductor wafer W is being executed (in other words, while the susceptor 2 is rotating).

[0075] The functional configuration of the state determination device 170 shown in Figure 8 is just one example, and it goes without saying that there are various functional configurations depending on the application and purpose. The division of the processing units, such as the imaging control unit 610, measurement unit 620, and determination unit 630 shown in Figure 8, is just one example. For example, at least two of the imaging control unit 610, measurement unit 620, or determination unit 630 may be integrated into one processing unit. Alternatively, at least one of the imaging control unit 610, measurement unit 620, or determination unit 630 may be divided into multiple processing units.

[0076] <Method for measuring warp amount> The method for measuring the warpage of a semiconductor wafer W will be explained with reference to Figures 9 and 10. Figure 9 shows a first example of a polarization image.

[0077] Figure 9 schematically shows an image of a susceptor 2 on which a semiconductor wafer W is placed, captured using camera 140. Image 700 shown in Figure 9 is an example of an image captured with camera 140 set to polarization mode.

[0078] As shown in Figure 9, Image 700 captures the susceptor 2 and the semiconductor wafer W placed on the recess 24 of the susceptor 2. Image 700 captures multiple markers 701 to 705 that are illuminated by polarized light 130 on the edge of the semiconductor wafer W. Figure 9 shows an example where five markers 701 to 705 are illuminated at equal intervals, but the number of markers and the spacing between them can be determined arbitrarily.

[0079] Hereafter, the direction from the center of the recess 24 toward the rotation center of the susceptor 2 will be referred to as the 12 o'clock direction, and the directions of the markers will be described in terms of 0 to 11 o'clock. For example, marker 703 shown in Figure 9 may be referred to as the 6 o'clock direction. In Figure 9, each marker is arranged at 30-degree intervals along the outer circumference of the semiconductor wafer W, and markers 701 to 705 correspond to the 4 to 8 o'clock directions, respectively.

[0080] In Figure 9, the positions indicated by reference numerals 711 to 715 are the specified positions for markers 701 to 705, respectively. The specified positions are the positions where markers 701 to 705 are imaged when there is no warping in the semiconductor wafer W.

[0081] When a semiconductor wafer W is brought into the chamber 1 and placed in the recess 24 of the susceptor 2, the semiconductor wafer W warps due to the temperature difference between the semiconductor wafer W and the surface of the susceptor 2. As a result, the positions of markers 701 to 705 move from their specified positions 711 to 715. The amount of movement of markers 701 to 705 increases with increasing warping. Therefore, the amount of warping of the semiconductor wafer W can be calculated based on the amount of movement of markers 701 to 705 (in other words, the distance between markers 701 to 705 and the specified positions 711 to 715).

[0082] Since the relative positions of susceptor 2 and camera 140 are fixed, the distance corresponding to one pixel in the image can be calculated based on the ratio of the focal length to the shooting distance. Therefore, the amount of warpage of the semiconductor wafer W can be calculated based on the number of pixels between each of the markers 701 to 705 and the pixels corresponding to the specified positions 711 to 715.

[0083] Figure 10 is a diagram illustrating the method for calculating the amount of warpage. As shown in Figure 10, the camera 140 has an image sensor 141 and a lens 142. The distance f between the image sensor 141 and the lens 142 is the focal length of the camera 140. The distance D between the semiconductor wafer W and the lens 142 when no warpage occurs is the shooting distance of the camera 140.

[0084] Assume that a semiconductor wafer W has warped by an angle θ. Angle θ is the angle between the surface of semiconductor wafer W when it is not warped and the surface of semiconductor wafer W' when it is warped. The height h of the warp when warping by angle θ occurs can be calculated as r × sin(θ), where r is the diameter of the semiconductor wafer W.

[0085] At this time, the distance Q between the virtual image 132 of the light source 131 projected onto the semiconductor wafer W and the virtual image 133 of the light source 131 projected onto the semiconductor wafer W' corresponds to the distance the marker has moved due to the warping of the semiconductor wafer W. The light source 131 is a light source used to illuminate the marker in polarized illumination 130. Here, the distance Q can be calculated by equation (1).

[0086]

number

[0087] The distance Q' on the image sensor 141 corresponding to distance Q can be calculated by equation (2).

[0088]

number

[0089] Transforming equation (2) with respect to the curvature angle θ yields equation (3). Therefore, the curvature angle θ can be calculated using the focal length f and the distance Q' (number of pixels) on the image sensor 141.

[0090]

number

[0091] In this embodiment, the detectable curvature height corresponds to the curvature height per pixel. For example, if the focal length f of the camera 140 is 12 mm and the pixel pitch of the image sensor 141 is 3.45 μm, then the curvature angle θ per pixel is 0.016 degrees according to equation (4).

[0092]

number

[0093] Furthermore, if the aperture r of the semiconductor wafer W is 300 mm, the height h of the warp per pixel is 0.086 mm according to equation (5). Therefore, in this embodiment, the detectable warp height is 0.086 mm, and it can be seen that the warp of the semiconductor wafer W can be detected with high accuracy.

[0094]

number

[0095] <Method for measuring clearance amount> The method for measuring the clearance amount of a semiconductor wafer W will be explained with reference to Figure 11. Figure 11 shows a second example of a polarization image.

[0096] Figure 11 shows images of the susceptor 2 on which the semiconductor wafer W is placed, captured using camera 140. The normal mode image is an example of an image captured with camera 140 set to normal mode. The polarization mode image is an example of a polarized image captured with camera 140 set to polarization mode.

[0097] As shown in Figure 11, in normal mode, the boundary between the semiconductor wafer W region and the susceptor 2 region is unclear, and the edge of the semiconductor wafer W cannot be clearly seen. On the other hand, in polarization mode, the boundary between the semiconductor wafer W region and the susceptor 2 region is clear, and the edge of the semiconductor wafer W can be clearly seen.

[0098] Since the positional relationship between the susceptor 2 and the camera 140 is fixed, the position of the outer periphery of the recess 24 of the susceptor 2 in the image captured by the camera 140 can be predetermined. Furthermore, the distance corresponding to one pixel in the image can be calculated based on the ratio of the focal length to the shooting distance. Therefore, the clearance amount of the semiconductor wafer W can be calculated based on the number of pixels between the pixels at the edge of the semiconductor wafer W and the pixels at the outer periphery of the recess 24 of the susceptor 2.

[0099] <Processing Procedure> The substrate processing method performed by the substrate processing apparatus 180 will be explained with reference to Figure 12. Figure 12 is a flowchart showing an example of a substrate processing method.

[0100] In step S1, the substrate processing apparatus 180 loads a semiconductor wafer W into the chamber 1. The semiconductor wafer W loaded into the chamber 1 is placed on a recess 24 formed on the surface of the susceptor 2. At this time, the semiconductor wafer W warps due to the temperature difference between it and the surface of the susceptor 2.

[0101] The state determination device 170 waits until a predetermined waiting time has elapsed. The waiting time is the time duration during which the warping of the semiconductor wafer W is at its maximum. In other words, the state determination device 170 waits until the warping of the semiconductor wafer W placed on the recess 24 of the susceptor 2 is at its maximum.

[0102] In step S2, the state determination device 170 instructs the camera 140 to capture a polarized image using the imaging control unit 610. The camera 140 captures a polarized image of the semiconductor wafer W placed on the recess 24 of the susceptor 2 in accordance with the control by the imaging control unit 610. The imaging control unit 610 acquires the polarized image captured by the camera 140. The imaging control unit 610 sends the polarized image acquired from the camera 140 to the measurement unit 620. The measurement unit 620 receives the polarized image from the imaging control unit 610.

[0103] In step S3, the state determination device 170 calculates the amount of movement of the markers included in the polarized image using the measurement unit 620. Specifically, the measurement unit 620 calculates the number of pixels Q' between the markers included in the polarized image and a specified position. If the polarized image includes multiple markers, the amount of movement should be calculated for each of the multiple markers.

[0104] In step S4, the state determination device 170 calculates the amount of warpage of the semiconductor wafer W based on the amount of marker movement calculated in step S4 using the measurement unit 620. Specifically, the measurement unit 620 calculates the warpage angle θ from the number of pixels Q' between the marker and the specified position using equation (3). Alternatively, the measurement unit 620 may calculate the warpage height h from the warpage angle θ using equations (4) and (5). The measurement unit 620 sends the calculated amount of warpage (warpage angle θ or warpage height h) to the determination unit 630. The determination unit 630 receives the amount of warpage from the measurement unit 620.

[0105] In step S5, the state determination device 170 determines, using the determination unit 630, whether the semiconductor wafer W is in a state suitable for substrate processing. Specifically, the determination unit 630 determines whether the amount of warping of the semiconductor wafer W is below a predetermined threshold.

[0106] If it is determined that the amount of warping of the semiconductor wafer W is below the threshold (YES), the determination unit 630 proceeds to step S6. On the other hand, if it is determined that the amount of warping of the semiconductor wafer W is not below the threshold (NO), the determination unit 630 proceeds to step S9.

[0107] In step S6, the substrate processing apparatus 180 rotates the susceptor 2. Specifically, the substrate processing apparatus 180 rotates the susceptor 2 until the recess 24 on which the semiconductor wafer W imaged in step S2 is placed and the adjacent recess 24 are positioned below the window 110. This makes the next recess 24 on which the semiconductor wafer W is placed available for imaging by the camera 140 through the window 110.

[0108] In step S7, the state determination device 170 determines whether the state determination has been completed for a set number of semiconductor wafers W. For example, if the susceptor 2 has five recesses 24 along the rotation direction, the device determines whether the state determination has been completed for five semiconductor wafers W.

[0109] If it is determined that the status determination of the set number of semiconductor wafers W is complete (YES), the status determination device 170 proceeds to step S8. On the other hand, if the status determination of the set number of semiconductor wafers W is not complete (NO), the status determination device 170 returns to step S2.

[0110] When the process returns from step S7 to step S2, the state determination device 170 repeats the processes from step S2 to step S6 for the next semiconductor wafer W. The state determination device 170 repeatedly executes the processes from step S2 to step S6 until it determines in step S6 that the state determination has been completed for the set number of semiconductor wafers W.

[0111] In step S8, the state determination device 170 notifies the control unit 100 of the substrate processing device 180 that it has completed the determination of the state of the semiconductor wafer W. In response to the notification from the state determination device 170, the control unit 100 executes a predetermined process (for example, a film deposition process). Specifically, the substrate processing device 180 starts rotating the susceptor 2 and executes the predetermined process on the semiconductor wafer W placed on the susceptor 2. When the predetermined process is completed, the substrate processing device 180 terminates the substrate processing.

[0112] In step S9, the state determination device 170 determines whether a specified time has elapsed since the semiconductor wafer W was placed on the susceptor 2 in step S1. The specified time may be predetermined according to process conditions, etc.

[0113] If it is determined that the specified time has elapsed (YES), the status determination device 170 proceeds to step S10. On the other hand, if it is determined that the specified time has not elapsed (NO), the status determination device 170 returns to step S2.

[0114] When the process returns from step S9 to step S2, the state determination device 170 repeats the processes from step S2 to step S6 for the current semiconductor wafer W. The state determination device 170 repeatedly executes the processes from step S2 to step S9 until it is determined in step S5 that the amount of warping of the semiconductor wafer W is below a threshold, or until it is determined in step S9 that a specified time has elapsed.

[0115] In step S10, the status determination device 170 notifies the control unit 100 of the substrate processing device 180 that the semiconductor wafer W is not in a state suitable for substrate processing. In response to the notification from the status determination device 170, the control unit 100 stops the operation of the substrate processing device 180. This allows the substrate processing device 180 to recognize the abnormality and check the status of the device. The status determination device 170 may also output an alarm signal. For example, the status determination device 170 may display an alarm on its output device 502. Alternatively, the status determination device 170 may transmit an alarm signal to the control unit 100 of the substrate processing device 180, causing the control unit 100 to display an alarm on its output device 502.

[0116] <Evaluation Results> The results of evaluating the measurement accuracy of the warpage amount according to this embodiment will be explained with reference to Figures 13 and 14.

[0117] In this evaluation, to simulate the warping of the semiconductor wafer W, a tilt was applied to the semiconductor wafer W using a lifting pin provided on the bottom surface of the susceptor 2. The lifting pin is a mechanism that pushes the semiconductor wafer W upward through a through hole formed on the bottom surface of the recess 24. In this embodiment, the semiconductor wafer W was pushed up horizontally using three lifting pins, but in this evaluation, the semiconductor wafer W was tilted using only one lifting pin.

[0118] Five markers were placed from the 4 o'clock to the 8 o'clock position, and the amount of movement along the X and Y axes was measured for each marker. The Y axis is the axis extending from the center of the recess 24 to the rotation center of the susceptor 2 (i.e., the 12 o'clock direction), and the X axis is the axis perpendicular to the Y axis (i.e., the 3 o'clock or 9 o'clock direction).

[0119] Figure 13 shows an example of the measurement accuracy evaluation results. Figure 13 is a graph plotting theoretical and measured values, with the horizontal axis representing the height of the lifting pin and the vertical axis representing the amount of movement from a specified position. Figure 13 shows the amount of movement on the X and Y axes for each of the markers at the 4 o'clock, 6 o'clock, and 8 o'clock positions. As shown in Figure 13, the theoretical and measured values ​​were in general agreement for all the evaluated markers. In addition, the evaluation also included the markers at the 5 o'clock and 7 o'clock positions, and in both cases, the theoretical and measured values ​​were in general agreement. Therefore, it was demonstrated that the amount of marker movement can be measured with high accuracy according to this embodiment.

[0120] Figure 14 shows an example of the evaluation results of measurement error. The measurement error was defined as the difference between the theoretical value and the measured value. Figure 14(A) is a table showing the measurement error statistics on the X axis for each marker in the 4 o'clock to 8 o'clock directions. Figure 14(B) is a table showing the measurement error statistics on the Y axis for each marker in the 4 o'clock to 8 o'clock directions. The statistics used were maximum value, mean, median, standard deviation, and interquartile deviation.

[0121] As shown in Figure 14, the mean or standard deviation for both the X and Y axes was 0.1 or less, indicating an overall favorable evaluation result. Therefore, this embodiment demonstrates that the amount of marker movement can be measured with high accuracy.

[0122] [Differentiation] In the above embodiment, the camera 140 is configured to image the inside of the chamber 1 by using the illumination reflector 125 to direct the light emitted by the illumination 120 into the window 110. The polarized illumination 130 is configured to illuminate a marker onto the semiconductor wafer W through the window 110. Since the light or polarized light incident on the window 110 is reflected by the surface of the window 110, noise or defects may occur in the image captured by the camera 140. Therefore, the substrate processing apparatus 180 may introduce various configurations to suppress reflection by the window 110.

[0123] For example, an anti-reflective coating may be formed on the window 110. The anti-reflective coating may be formed on only one side (the top surface) of the window 110, or on both sides (the top and bottom surfaces). By forming an anti-reflective coating on the surface of the window 110, reflection from the window 110 can be suppressed. As a result, the camera 140 can clearly image the marker.

[0124] For example, the polarized light 130 may illuminate the marker from a direction that forms a Brewster angle with respect to the surface of the semiconductor wafer W. The Brewster angle is the angle at which the reflectivity of p-waves is zero. By illuminating the marker at the Brewster angle, only s-waves are reflected, and reflection by the window 110 can be suppressed by shielding the s-waves with the polarized light 130. As a result, the camera 140 can image the marker clearly.

[0125] For example, the polarizing illumination 130 may have a DC-controlled light source. Using a pulse width modulation (PWM) controlled light source may cause flickering in the polarized light, potentially increasing noise in the image captured by the camera 140. By using a DC-controlled light source for the polarizing illumination 130 to illuminate the marker, marker flickering can be reduced. As a result, the camera 140 can capture a clear image of the marker.

[0126] <Effects of the Embodiment> A substrate processing apparatus 180 according to one embodiment of the present disclosure includes: a chamber 1 for processing a semiconductor wafer W by supplying a processing gas while heating the wafer; a susceptor 2 provided in the chamber 1 and having a plurality of recesses 24 on its upper surface for placing the semiconductor wafer W; a through hole formed in the susceptor 2 for passing a lifting pin that moves the semiconductor wafer W up and down when loading and unloading the wafer W; a rotation axis 22 for rotating the susceptor 2 so that the semiconductor wafer W passes through a plurality of processing areas; a camera 140 for capturing an image from above the susceptor 2 that includes polarization information of the semiconductor wafer W placed in the recesses 24; and a measuring unit 620 for measuring a physical quantity indicating the state of the semiconductor wafer W based on the polarization information contained in the image.

[0127] In one aspect, according to this embodiment, since a physical quantity indicating the state of the semiconductor wafer W is measured based on polarization information, the state of the semiconductor wafer W can be acquired with high accuracy. In another aspect, according to this embodiment, since the process can be executed when the semiconductor wafer W is in a state suitable for substrate processing, the semiconductor wafer W can be processed stably.

[0128] The measuring unit 620 may measure the amount of warpage at the edge of the semiconductor wafer W. The substrate processing apparatus 180 may be equipped with a polarizing light 130 that illuminates a marker on the edge of the semiconductor wafer W. The measuring unit 620 may measure the amount of warpage based on the position of the marker in the image. In one aspect, according to this embodiment, the amount of warpage of the semiconductor wafer W can be measured.

[0129] The polarized illumination 130 may irradiate a marker polarized in a predetermined direction. The polarized illumination 130 may irradiate multiple markers polarized in the same direction at different positions on the edge of the semiconductor wafer W. In one respect, according to this embodiment, the amount of warpage of the semiconductor wafer W can be measured with high accuracy.

[0130] The polarized illumination 130 may illuminate the marker with a DC-controlled light source. The polarized illumination 130 may illuminate the marker from a direction that forms a Brewster angle with the upper surface of the susceptor 2. The camera 140 may image the semiconductor wafer W through a window 110 provided on the upper surface of the chamber 1. The window 110 may have an anti-reflective coating formed on it. In one aspect, according to this embodiment, the marker irradiated onto the semiconductor wafer W can be clearly imaged.

[0131] The substrate processing apparatus 180 may include a determination unit 630 that determines the state of the semiconductor wafer W based on physical quantities indicating the state of the semiconductor wafer W. In one aspect, according to this embodiment, the state of the semiconductor wafer W can be determined with high accuracy.

[0132] In conventional technology, the warp of a semiconductor wafer is determined by imaging the susceptor from the side and determining whether or not the semiconductor wafer is imaged above the surface of the susceptor. However, conventional technology cannot quantify the warp of the semiconductor wafer. In this embodiment, the amount of warp of the semiconductor wafer is measured, so the warp of the semiconductor wafer can be quantified, and substrate processing can be controlled with high precision.

[0133] Furthermore, conventional technology cannot clearly image a susceptor that rotates at high speed during the process. In this embodiment, polarized images can be clearly captured with a short shutter speed, making it possible to determine the state of the semiconductor wafer even during the process. For example, since the clearance amount of the semiconductor wafer can be measured during the process, the generation of particles caused by contact between the semiconductor wafer and the side wall of the recess can be suppressed.

[0134] [Other embodiments] The substrate processing apparatus that performs the process including the substrate processing method of this disclosure is not limited to a heat processing apparatus. The substrate processing apparatus can be any type of apparatus, including Atomic Layer Deposition (ALD) apparatus, Capacitively Coupled Plasma (CCP), Inductively Coupled Plasma (ICP), Radial Line Slot Antenna (RLSA), Electron Cyclotron Resonance Plasma (ECR), or Helicon Wave Plasma (HWP).

[0135] Furthermore, the substrate processing apparatus of this disclosure can be applied to any apparatus that performs a predetermined process (e.g., film deposition, etching, etc.) on a substrate, whether it is a plasma-using apparatus or a plasma-free apparatus. In addition, the substrate processing apparatus of this disclosure can be applied to any single-wafer apparatus that processes substrates one at a time, a batch apparatus that processes multiple substrates at once, or a semi-batch apparatus that processes a smaller number of substrates at once than the number processed at once by a batch apparatus.

[0136] The substrate processing apparatus according to the embodiments disclosed herein is illustrative and not restrictive in all respects. The embodiments can be modified and improved in various ways without departing from the scope and spirit of the appended claims. The matters described in the above embodiments can be otherwise configured and combined in a non-consistent manner. [Explanation of Symbols]

[0137] W: Semiconductor wafer 1: Chamber 2: Susceptor 100: Control Unit 110: Window 120: Lighting 130: Polarized lighting 140: Camera 160: Processing Unit 170: State determination device 180: Substrate processing equipment 610: Imaging control unit 620: Measurement Department 630: Judgment Department

Claims

1. A processing container that processes the object to be processed by supplying a processing gas while heating it, A platform provided inside the processing container and having a plurality of recesses on its upper surface for placing the object to be processed, The aforementioned mounting platform has a hole through which a pin passes when the object to be processed is moved up and down during loading and unloading, A rotating mechanism that rotates the aforementioned stand so that the object to be processed passes through multiple processing areas, An imaging unit captures an image from above the aforementioned stand, which includes polarization information of the object to be processed placed in the recess, A measuring unit that measures a physical quantity indicating the state of the object to be treated based on the polarization information contained in the image, A substrate processing apparatus equipped with the following:

2. The measuring unit measures the amount of warping at the end of the workpiece. The substrate processing apparatus according to claim 1.

3. The system further includes an illumination unit that illuminates a marker at the end of the object to be processed, The amount of warping is measured based on the position of the marker in the aforementioned image. The substrate processing apparatus according to claim 2.

4. The illumination unit irradiates the marker, which is polarized in a predetermined direction. The substrate processing apparatus according to claim 3.

5. The illumination unit illuminates multiple markers polarized in the same direction at different positions on the end of the object to be processed. The substrate processing apparatus according to claim 4.

6. The illumination unit illuminates the marker with a DC-controlled light source. The substrate processing apparatus according to claim 4.

7. The illumination unit illuminates the marker from a direction that forms a Brewster angle with the upper surface of the stand described above. The substrate processing apparatus according to claim 4.

8. The measuring unit measures the distance between the end of the workpiece and the outer circumference of the recess. The substrate processing apparatus according to claim 1.

9. The imaging unit images the object to be processed through a window provided on the upper surface of the processing container. The substrate processing apparatus according to claim 1.

10. The aforementioned window has an anti-reflective coating formed on it. The substrate processing apparatus according to claim 9.

11. The system further includes a determination unit that determines the state of the object to be processed based on the aforementioned physical quantity. A substrate processing apparatus according to any one of claims 1 to 10.

12. A processing container that processes the object to be processed by supplying a processing gas while heating it, A platform provided inside the processing container and having a plurality of recesses on its upper surface for placing the object to be processed, The aforementioned mounting platform has a hole through which a pin passes when the object to be processed is moved up and down during loading and unloading, A rotating mechanism that rotates the aforementioned stand so that the object to be processed passes through multiple processing areas, An imaging unit that images the object to be processed, which is placed in the recess, from above the stand described above, A substrate processing method performed by a substrate processing apparatus comprising: The imaging unit performs the step of capturing an image that includes polarization information of the object to be processed, A step of measuring a physical quantity indicating the state of the object to be treated based on the polarization information contained in the image, A substrate processing method having the following characteristics.

Images