Plasma processing apparatus, positional displacement detection apparatus, and positional displacement correction method

Abstract

The present invention provides a technique that enables direct detection of a misalignment amount of a sample (wafer) with respect to a placement section (a wafer installation section) when the sample is to be processed, and that enables the sample to be positioned highly accurately with respect to the placement section. The present invention comprises: a sample table equipped with a placement section on which a sample is placed; and a misalignment amount detection device for detecting a misalignment amount of the sample with respect to the placement section. The present invention provides a technique with which the misalignment amount of the sample with respect to the placement section is detected by the misalignment amount detection device on the basis of a first image including an outer peripheral portion of the sample and a second image including an outer peripheral portion of the placement section.

Description

Technical Field

[0004] , , , , , , , , , ,

[0006] , , , ,

[0005] , , , , , , ,

[0003] ,

[0001] The present disclosure relates to a plasma processing apparatus, a misalignment amount detection apparatus, and a misalignment amount correction method.

Background Art

[0002] In recent years, there has been an increasing demand for power saving and high speed in semiconductor devices from the market, and the trend towards more complex and highly integrated device structures is remarkable. Along with this, the accuracy required for the wafer installation position when processing a wafer as a sample has been increasing year by year from the viewpoints of yield and reproducibility.

[0003] On the other hand, the performance of imaging devices for capturing images has been improving year by year, and examples of using imaging devices for positioning conveyed objects have also been proposed. For example, in Patent Document 1, a misalignment amount detection apparatus that calculates the misalignment amount of a conveyed object with respect to a conveyance mechanism based on an image captured by an image sensor has been proposed.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In Patent Document 1, the misalignment amount of a conveyed object with respect to a conveyance mechanism is detected, but the installation position of the wafer when processing the wafer cannot be directly detected. Also, in order to detect the misalignment amount with high accuracy, it is desirable to be able to detect the outer periphery of the wafer installation portion and the outer periphery position of the wafer.

[0006] The present disclosure provides a technique for directly detecting the misalignment amount of a sample (wafer) with respect to a placement portion (wafer installation portion) when processing the sample, and enabling highly accurate positioning of the sample with respect to the placement portion.

Means for Solving the Problems

[0007] A plasma processing apparatus according to one aspect of the present disclosure comprises a sample stage having a mounting section on which a sample is placed, and a positional displacement detection device for detecting the amount of positional displacement of the sample relative to the mounting section described above, The aforementioned positional displacement detection device A first image including the outer periphery of the sample and a second image including the outer periphery of the aforementioned part. The difference processing is performed on the difference processed image Based on the amount of displacement of the sample relative to the previously described mounting part can check It will be released.

[0008] In other words, in order to solve the above problems, one representative wafer position detection method according to this disclosure relates to a detection method for a positional displacement detection device that detects the amount of positional displacement of a wafer relative to a wafer mounting section in a plasma processing apparatus equipped with a sample stage having a mounting section (wafer mounting section) on which a sample (wafer) is placed. The positional displacement detection device is positioned above the wafer mounting section and includes an imaging device that captures a first image including the outer periphery of the wafer and a second image including the outer periphery of the wafer mounting section, respectively, and detects and calculates the amount of positional displacement between the wafer mounting section and the wafer based on a plurality of images including the first and second images captured by the imaging device. The calculation of the positional displacement can be performed, for example, in an image processing unit. [Effects of the Invention]

[0009] According to this disclosure, a technology is provided that can directly detect the amount of displacement of the sample relative to the mounting surface when processing the sample, and enable high-precision positioning of the sample relative to the mounting surface. [Brief explanation of the drawing]

[0010] [Figure 1] Figure 1 shows an example of a detection method for detecting wafer misalignment relative to the wafer mounting section, which is a first embodiment. [Figure 2] Figure 2 shows an example of a detection method for detecting wafer misalignment relative to the wafer mounting section, which is the first embodiment. [Figure 3]Figure 3 shows an example of a detection method for detecting wafer misalignment relative to the wafer mounting section, which is the first embodiment. [Figure 4] Figure 4 shows an example of a detection method for detecting positional displacement of a wafer on a transport mechanism relative to the wafer placement section, which is a second embodiment. [Figure 5] Figure 5 shows an example of a detection method for detecting the positional displacement of a wafer on the transport mechanism relative to the wafer placement section, which is a second embodiment. [Figure 6] Figure 6 shows an example of a detection method for detecting positional displacement of a wafer on a wafer mounting section, which is a third embodiment. [Figure 7] Figure 7 shows an example of a detection method for detecting misalignment of a wafer on a wafer mounting section, which is a third embodiment. [Figure 8] Figure 8 shows an example of a detection method, which is a fourth embodiment, for detecting the positional displacement of a wafer relative to the wafer mounting section using image difference processing. [Figure 9] Figure 9 shows an example of a detection method, which is a fifth embodiment, for detecting the positional displacement of a wafer relative to the wafer mounting section using image centroid position calculation processing. [Figure 10] Figure 10 shows an example of a detection method, which is the sixth embodiment, for detecting wafer misalignment relative to the wafer mounting section by correcting the position of the imaging device. [Figure 11] Figure 11 shows an example of a detection method, which is the seventh embodiment, for detecting the positional displacement of a wafer relative to the wafer mounting section using multiple imaging devices. [Figure 12] Figure 12 shows an example of a detection method for detecting wafer misalignment relative to the wafer mounting section, which is the eighth embodiment, by correcting for the influence of a structure that is transparent to visible light. [Figure 13] Figure 13 shows an example of a detection method for detecting wafer misalignment relative to the wafer mounting section, which is the eighth embodiment, by correcting for the influence of a structure that is transparent to visible light. [Figure 14]FIG. 14 is a diagram showing an example of a correction method for correcting the misalignment of a wafer with respect to a wafer mounting portion according to the ninth embodiment. [Figure 15] FIG. 15 is a diagram showing an example of a correction method for correcting the misalignment of a wafer with respect to a wafer mounting portion according to the tenth embodiment. BEST MODE FOR CARRYING OUT THE INVENTION

[0011] Hereinafter, embodiments will be described with reference to the drawings. However, in the following description, the same reference numerals may be assigned to the same components and repeated descriptions may be omitted. Note that the drawings may be schematically represented compared to the actual aspect for the sake of clearer explanation, but they are merely examples and do not limit the interpretation of the present invention.

[0012] [First Embodiment] FIGS. 1, 2, and 3 are diagrams showing an example of a detection method for detecting the misalignment of a wafer with respect to a wafer mounting portion according to the first embodiment of the present disclosure. An example of a plasma processing apparatus using this detection method is shown in (a) of FIG. 1. The plasma processing apparatus 100 of the present embodiment includes a plasma processing chamber 101 and a wafer mounting portion 102. The wafer mounting portion 102 is a mounting portion on which a wafer as a sample is placed, and this mounting portion 102 is provided on a sample stage. An exhaust device 109 for performing vacuum exhaust is connected to the plasma processing chamber 101. The sample stage having the wafer mounting portion 102 is made of aluminum or titanium as a material, and a sprayed film made of alumina ceramics or the like is disposed on the upper surface. The imaging device 103 is held by an imaging device holding member 104 and is connected to the plasma processing chamber 101. The image processing unit 105 is arbitrarily connected to the imaging device 103, for example, by a USB cable or the like, and transfers and processes the captured image. At this time, an example of the image acquired by the imaging device 103 is shown in (a) of FIG. 2. An image 202 obtained by observing the wafer mounting portion 102 from directly above is obtained.

[0013] Also, an example of a plasma processing apparatus using this detection method is shown in (b) of FIG. 1. In addition to the configuration of (a) of FIG. 1, a wafer 106 is disposed above the wafer placement unit 102. The wafer 106 is held by a transfer mechanism (not shown), or held on pins (not shown), or held on the wafer placement unit 102, etc. As long as it is above the wafer placement unit 102, the holding method is not limited. Further, the wafer 106 is made of, for example, silicon (Si), black silicon (Black Si), silicon nitride (SiN), silicon dioxide (SiO2), silicon carbide (silicon carbide: SiC), etc., and it is more desirable that the reflectance is low. An example of the image acquired by the imaging device 103 at this time is shown in (b) of FIG. 2. An image 206 of the wafer 106 observed from directly above is obtained.

[0014] From the image (second image) 202 of the wafer placement unit 102 observed from directly above and the image (first image) 206 of the wafer 106 observed from directly above thus obtained, the positional deviation of the wafer 106 with respect to the wafer placement unit 102 is detected. The image 206, which is the first image, is an image including the outer peripheral portion of the wafer 106, which is a sample disposed above the placement unit 102, or an image including the entire wafer 106, which is the sample. The image 202, which is the second image, is an image including the outer peripheral portion of the placement unit 102, or an image including the entire placement unit 102.

[0015] As shown in (c) of FIG. 2, as an example, the image processing unit 105 creates a difference image 207 from the image 202 and the image 206. Since the wafer 106 has a larger diameter than the wafer placement unit 102 and is further disposed above the wafer placement unit 102, the wafer 106 is photographed larger than the wafer placement unit 102. Therefore, the difference image 207 shows how much the circular shape of the wafer 106 observed from directly above exceeds the circular shape of the wafer placement unit 102 observed from directly above. By observing this profile, it becomes possible to detect the amount of positional deviation of the wafer 106 with respect to the wafer placement unit 102. Also, by acquiring a plurality of images 202 and 206 respectively, noise can be reduced and more accurate detection of the amount of positional deviation is also possible.

[0016] In other words, the image processing unit 105 is considered a positional displacement detection device that detects the amount of positional displacement of the sample 106 relative to the mounting unit 102. The image processing unit 105 detects the amount of positional displacement of the sample 106 relative to the mounting unit 102 based on the first image 206 and the second image 202. In detecting the amount of positional displacement, the image processing unit 105 performs difference processing between image 202 and image 206 to generate a difference image 207. Then, the image processing unit 105 detects the amount of positional displacement of the sample 106 relative to the mounting unit 102 based on the difference image that has been processed.

[0017] Figure 3 shows an example of an image acquired by the imaging device 103 when a positional displacement occurs in the wafer 106. Figure 3(a) is an image (second image) 302 of the wafer mounting section 102 observed from directly above, which is equivalent to image 202. Figure 3(b) is an image (first image) 306 of the wafer 106 with positional displacement observed from directly above, and Figure 3(c) is a difference image 307 created from images 302 and 306. In this way, the image processing unit 105 creates the difference image 307 and can further detect the amount of positional displacement of the wafer 106 relative to the wafer mounting section 102 from its profile.

[0018] [Second Example] Figures 4 and 5 show an example of a detection method for detecting wafer misalignment relative to the wafer mounting section, which is a second embodiment of the present disclosure. As shown in Figure 4, the wafer 106 is held and positioned above the wafer mounting section 102 by the transport mechanism 407. An example of an image (first image) acquired by the imaging device 103 at this time is shown in Figure 5(b). An image (first image) 506 is obtained by observing the wafer 106, which is held by the transport mechanism 407 and positioned above the wafer mounting section 102, from directly above. The first image 506 is an image that includes the outer periphery of the sample 106 positioned above the mounting section 102. The image (second image) 502 shown in Figure 5(a), which observes the wafer mounting section 102 from directly above, is acquired before the wafer 106 is transported into the plasma processing chamber 101. From the image 502 of the wafer mounting section 102 observed from directly above and the image 506 of the wafer 106 observed from directly above, the wafer misalignment relative to the wafer mounting section is detected. As an example, as shown in Figure 5(c), the image processing unit 105 creates a difference image 507 from images 502 and 506. By observing this profile, it becomes possible to detect the amount of misalignment of the wafer 106 relative to the wafer mounting unit 102. At this time, since the wafer 106 is held by the transport mechanism 407, it becomes easy to correct the amount of misalignment and re-detect the amount of misalignment at the corrected position by controlling the transport mechanism 407.

[0019] [Third embodiment] Figures 6 and 7 show an example of a detection method for detecting wafer misalignment relative to the wafer mounting section, which is a third embodiment of the present disclosure. As shown in Figure 6, the wafer 106 is placed on the wafer mounting section 102. An example of an image (first image) acquired by the imaging device 103 at this time is shown in Figure 7(b). An image (first image) 706 is obtained by observing the wafer 106 placed on the wafer mounting section 102 from directly above. The image (second image) 702 of the wafer mounting section 102, shown in Figure 7(a), is acquired before the wafer 106 is brought into the plasma processing chamber 101. From the image 702 of the wafer mounting section 102 observed from directly above and the image 706 of the wafer 106 observed from directly above, the wafer misalignment relative to the wafer mounting section is detected. As an example, as shown in Figure 7(c), the image processing unit 105 creates a difference image 707 from images 702 and 706. By observing this profile, it becomes possible to detect the amount of misalignment of the wafer 106 relative to the wafer mounting section 102. At this time, the wafer 106 is placed and held on the wafer mounting section 102. In other words, the wafer 106 is actually placed in the position where plasma processing will be performed. Therefore, this method makes it possible to detect in detail the amount of misalignment of the wafer 106 when it is actually processed.

[0020] [Fourth embodiment] Figure 8 shows an example of a detection method for detecting wafer misalignment relative to a wafer mounting section, which is a fourth embodiment of the present disclosure. Figure 8(a) is a difference image 807 created when a wafer misalignment occurs. At this time, the image processing unit 105 focuses on the left region 807a and the right region 807b of the difference image 807, respectively, and acquires profiles. When profiles are acquired, a profile 808a of the left region 807a and a profile 808b of the right region 807b are obtained, as shown in Figure 8(b). If the width Xa of the profile of the left region 807a is 100 pixels and the width Xb of the profile of the right region 807b is 200 pixels, then the wafer 106 can be said to be shifted to the right by (200 - 100) / 2 = 50 pixels. If one pixel is 0.1 mm, the amount of misalignment in the X direction can be detected as 5 mm. The width of the profile can also be acquired by processing multiple lines or by performing appropriate interpolation to obtain sub-pixels. Similarly, in the Y direction, profiles of the upper and lower regions are acquired, and by looking at the difference between the upper and lower regions, the amount of displacement in the Y direction can also be detected. Furthermore, by performing the same processing for directions other than up, down, left, and right, the amount of positional displacement can be detected with higher accuracy. In this method, the positional displacement detection device 105 performs difference processing between the first image and the second image, and the amount of positional displacement of the sample relative to the mounting unit 102 is detected based on the difference-processed image. This method can cancel out external disturbances such as brightness unevenness or blurring in the images (first image, second image) through difference processing, so it is possible to detect the amount of positional displacement of the wafer 106 even in such environments.

[0021] [Fifth Example] Figure 9 shows an example of a detection method for detecting the positional displacement of a wafer relative to a wafer mounting section, which is a fifth embodiment of the present disclosure. The image processing unit 105 calculates the centroid position of the wafer mounting section 102 when observed from directly above using an image (second image) 902 of the wafer mounting section 102 observed from directly above. The image processing unit 105 calculates the centroid position of the wafer 106 when observed from directly above using an image (first image) 906 of the wafer 106 observed from directly above. By comparing the centroid positions of the wafer mounting section 102 and the wafer 106 calculated in this way, the image processing unit 105 can detect the amount of positional displacement of the wafer 106 relative to the wafer mounting section 102. In other words, in this method, the positional displacement detection device 105 detects the amount of positional displacement of the sample 106 relative to the mounting section 102 based on the centroid position of the sample 106 calculated using the first image 901 and the centroid position of the mounting section 102 calculated using the second image 902. For example, if the center of gravity of the wafer placement area is calculated to be X:2600.123, Y:1900.456 pixels in image 902, and the center of gravity of the wafer is calculated to be X:2650.789, Y:1910.012 pixels in image 906, then it can be said that there is a shift of 50.666 pixels in the X direction and 9.556 pixels in the Y direction. If one pixel is 0.1 mm, then the amount of shift in the X direction can be calculated to be 5.666 mm and the amount of shift in the Y direction to be 0.9566 mm. This method using the center of gravity position uses a large number of pixels for position calculation, making it possible to calculate the amount of positional shift with higher accuracy. However, if there are disturbances such as brightness unevenness or blur in the image, errors may occur in the selection of the wafer placement area or wafer region. For this reason, it is more desirable to select an appropriate position detection image processing or to perform multiple position detection image processing depending on the chamber environment and the acquired image.

[0022] [Sixth Embodiment] Figure 10 shows an example of a detection method for detecting wafer misalignment relative to the wafer mounting section, which is a sixth embodiment of the present disclosure. As shown in Figure 10(a), the center of the imaging device 1003 and the wafer mounting section 102 may be misaligned due to the mounting accuracy of the imaging device 1003 or the imaging device holding member 1004, or due to misalignment of the lens center of the imaging device 1003, or due to intentional setting. In such cases, as shown in Figures 10(b) and (c), especially when the wafer 106 is positioned above, the left region 1007a and the right region 1007b, which should be equal if the center positions of the wafer 106 and the wafer mounting section 102 are aligned, may appear to be misaligned in the image. At this time, the image processing unit 105 calculates the amount of center misalignment between the imaging device 1003 and the wafer mounting unit 102 from the image (second image) 1002 taken by observing the wafer mounting unit 102 from directly above, as shown in Figure 10(d), and corrects the position of the imaging device 1003 to detect the amount of positional misalignment of the wafer 106 relative to the wafer mounting unit 102. In other words, in this method, the positional misalignment detection device 105 calculates a correction amount for correcting the position of the imaging device 1003 that images the sample 106 or the mounting unit 102 using the second image 1002. After the correction amount calculated is applied to the position of the imaging device 1003, the amount of positional misalignment of the sample 106 relative to the mounting unit 102 is detected. This makes it possible to detect the amount of wafer misalignment even when the centers of the imaging device 1003 and the wafer mounting unit 102 are misaligned. Furthermore, by acquiring multiple images while changing the height of the wafer 106, more detailed positional correction that also takes into account the tilt of the imaging device 1003 becomes possible.

[0023] [Seventh Embodiment] Figure 11 shows an example of a detection method for detecting wafer misalignment relative to the wafer mounting section, which is a seventh embodiment of the present disclosure. As shown in Figure 11(a), the plasma processing apparatus 100 may have multiple imaging devices 1103a, 1103b. That is, the plasma processing apparatus 100 further includes multiple imaging devices 1103a, 1103b arranged above the mounting section 102 to image the sample 106 or the mounting section 102. As shown in Figure 11(b), each imaging device 1103a, 1103b acquires magnified images (second images) 1102a, 1102b of the outer periphery of the wafer mounting section 102 and magnified images (first images) 1106a, 1106b of the outer periphery of the wafer 106, and the image processing unit 1105 performs, for example, difference processing to create images 1107a, 1107b. From the profiles of these two images 1107a and 1107b, it becomes possible to detect the amount of misalignment of the wafer 106 relative to the wafer mounting section 102. By acquiring magnified images in this way, for example, one pixel becomes equivalent to 0.01 mm, enabling more accurate detection of wafer misalignment.

[0024] [Eighth embodiment] Figure 12 shows an example of a detection method for detecting wafer misalignment relative to the wafer mounting section, which is an eighth embodiment of the present disclosure. As shown in Figures 12(a) and (b), the plasma processing chamber 101 may have a visible light transparent structure (quartz top plate 1210, quartz shower plate 1211) placed between the mounting section 102 and the imaging device 103. The visible light transparent structure is, for example, a quartz top plate 1210 that maintains a vacuum or a quartz shower plate 1211 that has gas holes, and there may be multiple such structures. Here, distortion may occur in the quartz top plate 1210 or the quartz shower plate 1211 due to aging or other reasons. At this time, as shown in Figures 13(a) and (b), distortion may also occur in the image (second image) 1302 of the wafer mounting section 102 observed from directly above and the image (first image) 1306 of the wafer 106 observed from directly above. In this case, the image processing unit 105 determines and corrects the degree of distortion from the deviation of the acquired wafer mounting section 102 and wafer 106 from a perfect circle, and from the slope of the profile of the difference image 1307 shown in Figure 13(c), and then detects the amount of wafer displacement. Furthermore, if the distortion is above a certain level and correction is difficult, a warning to that effect may be issued. In other words, in this method, the displacement detection device 105 calculates the influence of the structures (1210, 1211) on the first image 1306 or the second image 1302. After the calculated influence of the structures (1210, 1211) is corrected, the amount of displacement of the sample 106 relative to the mounting section 102 is detected.

[0025] [Ninth Embodiment] Figure 14 shows an example of a correction method for correcting wafer misalignment relative to the wafer mounting section, which is a ninth embodiment of the present disclosure. As shown in Figure 14(a), the wafer 106 is held by a transport mechanism 407 controlled by a control unit 1412 and positioned above the wafer mounting section 102. As shown in Figure 14(b), the image processing unit 105 creates a difference image 1407a of an image (second image) taken by the imaging device 1403 before the wafer 106 is transported into the plasma processing chamber 101, showing the entire surface of the wafer mounting section 102 from directly above, and an image (first image) taken by the imaging device 1403, showing the entire surface of the wafer 106 held by the transport mechanism 407 and positioned above the wafer mounting section 102, and displays it on the display unit 1413. The image (first image) showing the entire surface of the wafer 106 from directly above is updated as needed, for example at 30 fps, and the difference image 1407a is updated accordingly. Therefore, by operating the transport mechanism 407 with the control unit 1412, the difference image 1407a at the current position of the wafer 106 is displayed in real time on the display unit 1413. By operating the control unit 1412 to display the difference image 1407b, it becomes possible to control the position of the wafer 106 while constantly checking the amount of misalignment. It is also preferable to display the current amount of misalignment on the display unit at the same time. This makes it possible to quickly correct the misalignment of the wafer relative to the wafer mounting section.

[0026] In other words, this correction method relates to a positional displacement correction method for a plasma processing apparatus 100 equipped with a sample stage having a mounting section 102 on which a sample 106 is placed, which detects the amount of positional displacement of the sample 106 relative to the mounting section 102 and corrects the detected amount of positional displacement of the sample 106 relative to the mounting section 102. This positional displacement correction method comprises the steps of: detecting the amount of positional displacement of the sample 102 relative to the mounting section 102 based on a difference image (1407a) between a first image including the outer periphery of the sample 106 and a second image including the outer periphery of the mounting section; and correcting the detected amount of positional displacement of the sample 106 relative to the mounting section 102 by operating the control unit 1412 so that the difference image 1407b is displayed.

[0027] [Tenth embodiment] Figure 15 shows an example of a correction method for correcting the positional misalignment of a wafer relative to the wafer mounting section, which is the tenth embodiment of this disclosure. In the ninth embodiment (Figure 14), the centers of the imaging device 1403 and the wafer mounting section 102 may be misaligned due to the mounting accuracy of the imaging device 103 or the imaging device holding member 104, or due to misalignment of the lens center of the imaging device 1403, or due to intentional setting. As shown in the sixth embodiment (Figure 10), correction is performed from the amount of center misalignment between the imaging device 1403 and the wafer mounting section 102, and the appropriate current amount of positional misalignment is displayed. At this time, a discrepancy may occur between the display of the amount of positional misalignment and the difference image 1507a, which may confuse the operator. Therefore, the image processing unit 105 uses the amount of center misalignment between the imaging device 1403 and the wafer mounting section 102 to correct the image (first image) of the entire wafer 106 observed from directly above, and then creates a difference image 1507b which is displayed on the display unit 1413, so that the operator can quickly correct the positional misalignment of the wafer relative to the wafer mounting section without confusion. The steps of the tenth embodiment of this disclosure are further added to the method for correcting the misalignment amount described in the ninth embodiment. That is, the method for correcting the misalignment amount of the ninth embodiment further includes the steps of calculating a correction amount for correcting the position of the imaging device 1003 that images the sample 106 or the mounting unit 102 using a second image, and performing a difference processing between the first image reflecting the calculated correction amount and the second image reflecting the calculated correction amount.

[0028] The embodiments described above are explained in detail for the purpose of clearly illustrating the present invention, and are not necessarily limited to those comprising all the described configurations. Furthermore, it is possible to replace parts of the configuration of one embodiment with the configuration of another embodiment, and it is also possible to add configurations from other embodiments to the configuration of one embodiment. In addition, it is possible to add, delete, or replace parts of the configuration of each embodiment with other configurations. [Explanation of symbols]

[0029] 101: Plasma processing chamber, 102: Wafer mounting section, 103: Imaging equipment, 104: Imaging equipment holding member, 105: Image processing unit, 106: Wafer, 107: Vacuum processing chamber, 109: Exhaust system.

Claims

1. A sample stand having a mounting section on which the sample is placed, The system includes a positional displacement detection device for detecting the amount of positional displacement of the sample relative to the mounting section, A plasma processing apparatus characterized in that the positional displacement amount detection device performs difference processing between a first image including the outer periphery of the sample and a second image including the outer periphery of the aforementioned placement area, and detects the amount of positional displacement of the sample relative to the aforementioned placement area based on the difference-processed image.

2. A sample stand comprising a mounting section on which a sample is placed, The device includes a positional displacement detection device that detects the amount of positional displacement of the sample relative to the aforementioned placement area based on a first image including the outer periphery of the sample and a second image including the outer periphery of the aforementioned placement area. A plasma processing apparatus characterized in that, by the positional displacement detection device, a correction amount for correcting the position of the sample or the imaging device that images the above-mentioned mounting area is calculated using the second image, and after the position of the imaging device is corrected by the calculated correction amount, the positional displacement amount of the sample with respect to the above-mentioned mounting area is detected.

3. A sample stand comprising a mounting section on which a sample is placed, A positional displacement detection device for detecting the amount of positional displacement of the sample relative to the mounting section, An imaging device for imaging the sample or the aforementioned mounting area, The system comprises a transparent structure positioned between the mounting section and the imaging device, A plasma processing apparatus characterized in that the positional displacement amount detection device calculates the influence of the structure on a first image including the outer periphery of the sample or a second image including the outer periphery of the aforementioned placement area, and after the calculated influence of the structure is corrected, the positional displacement amount of the sample with respect to the aforementioned placement area is detected.

4. In the plasma processing apparatus according to any one of claims 1 to 3, The plasma processing apparatus is characterized in that the first image is an image including the outer periphery of the sample positioned above the aforementioned mounting section.

5. In the plasma processing apparatus according to any one of claims 1 to 3, The system further includes a transport mechanism for transporting the aforementioned sample, The plasma processing apparatus is characterized in that the sample is held above the aforementioned storage unit by the transport mechanism.

6. In the plasma processing apparatus according to any one of claims 1 to 3, The plasma processing apparatus is characterized in that the sample is placed on the aforementioned mounting section.

7. In the plasma processing apparatus according to any one of claims 1 to 3, The first image is an image that includes the entire sample. The plasma processing apparatus is characterized in that the second image is an image including the entire mounting portion described above.

8. In the plasma processing apparatus according to claim 7, A plasma processing apparatus characterized in that the positional displacement amount of the sample relative to the aforementioned mounting part is detected by the positional displacement amount detection device based on the centroid position of the sample calculated using the first image and the centroid position of the aforementioned mounting part calculated using the second image.

9. In the plasma processing apparatus according to any one of claims 1 to 3, A plasma processing apparatus further comprising a plurality of imaging devices arranged above the mounting section for imaging the sample or the mounting section.

10. In a plasma processing apparatus equipped with a sample stage having a mounting section on which a sample is placed, a positional displacement detection device for detecting the amount of positional displacement of the sample relative to the mounting section described above, A positional displacement detection device characterized in that a difference processing is performed between a first image including the outer periphery of the sample and a second image including the outer periphery of the aforementioned placement area, and the amount of positional displacement of the sample relative to the aforementioned placement area is detected based on the difference processed image.

11. A plasma processing apparatus comprising a sample stage having a mounting portion on which a sample is placed, wherein a positional displacement amount detection device detects the amount of positional displacement of the sample relative to the mounting portion based on a first image including the outer periphery of the sample and a second image including the outer periphery of the mounting portion, A positional displacement detection device characterized in that a correction amount for correcting the position of the imaging device that images the sample or the aforementioned mounting area is calculated using the second image, and after the calculated correction amount is applied to the position of the imaging device, the amount of positional displacement of the sample with respect to the aforementioned mounting area is detected.

12. A plasma processing apparatus comprising a sample stage having a mounting section on which a sample is placed, an imaging device for imaging the sample or the mounting section, and a transparent structure disposed between the mounting section and the imaging device, wherein a positional displacement detection device for detecting the amount of positional displacement of the sample with respect to the mounting section, A positional displacement detection device characterized in that the influence of the structure on a first image including the outer periphery of the sample or a second image including the outer periphery of the aforementioned placement area is calculated, and after the calculated influence of the structure is corrected, the amount of positional displacement of the sample relative to the aforementioned placement area is detected.

13. In the positional displacement detection device according to any one of claims 10 to 12, The positional displacement detection device is characterized in that the first image is an image that includes the outer periphery of the sample placed above the aforementioned mounting part.

14. In a plasma processing apparatus equipped with a sample stage having a mounting section on which a sample is placed, a method for correcting positional displacement of the sample relative to the mounting section and correcting the detected positional displacement of the sample relative to the mounting section, The process involves performing a difference operation between a first image including the outer periphery of the sample and a second image including the outer periphery of the aforementioned mounting area, and detecting the amount of positional displacement of the sample relative to the aforementioned mounting area based on the difference-processed image. A method for correcting misalignment, characterized by comprising the step of correcting the amount of misalignment of the sample relative to the detected mounting portion.

15. A plasma processing apparatus comprising a sample stage having a mounting section on which a sample is placed, wherein a method for correcting positional displacement of the sample relative to the mounting section is used to detect a first image including the outer periphery of the sample and a second image including the outer periphery of the mounting section, and corrects the detected positional displacement of the sample relative to the mounting section, A step of calculating a correction amount for correcting the position of the imaging device that images the sample or the aforementioned mounting area using the second image, and after correcting the position of the imaging device by the calculated correction amount, detecting the amount of positional displacement of the sample relative to the aforementioned mounting area, A method for correcting misalignment, characterized by comprising the step of correcting the amount of misalignment of the sample relative to the detected mounting portion.

16. A plasma processing apparatus comprising a sample stage having a mounting section on which a sample is placed, an imaging device for imaging the sample or the mounting section, and a transparent structure disposed between the mounting section and the imaging device, wherein a method for correcting the amount of positional displacement of the sample relative to the mounting section and the detected amount of positional displacement of the sample relative to the mounting section, A step of calculating the influence of the structure on a first image including the outer periphery of the sample or a second image including the outer periphery of the aforementioned mounting area, correcting the calculated influence of the structure, and then detecting the amount of positional displacement of the sample relative to the aforementioned mounting area. A method for correcting misalignment, characterized by comprising the step of correcting the amount of misalignment of the sample relative to the detected mounting portion.

17. In the positional displacement correction method described in claim 16, A method for correcting positional misalignment, further comprising the steps of calculating a correction amount for correcting the position of the imaging device using the second image, and performing a difference processing between the first image reflecting the calculated correction amount and the second image reflecting the calculated correction amount.

Images