Semiconductor process chamber

Abstract

A semiconductor process chamber disclosed by the present invention comprises a cavity, a thermal imaging device, a heating device and a control device, the thermal imaging device is used for collecting a thermal image of a wafer to be detected in the cavity, the control device is connected with the thermal imaging device and the heating device, and the control device is used for obtaining the thermal image of the wafer to be detected collected by the thermal imaging device. Obtaining a temperature value of each pixel point belonging to the to-be-detected wafer according to the thermal image, dividing the to-be-detected wafer into a plurality of areas, determining the temperature value of each area of the to-be-detected wafer according to the temperature value of each pixel point in each area of the to-be-detected wafer, and determining the temperature value of each area of the to-be-detected wafer according to the temperature value of each area of the to-be-detected wafer. According to the method, the to-be-heated area of the to-be-tested wafer is determined, and the heating device is controlled to heat the to-be-heated area of the to-be-tested wafer, so that the to-be-heated area of the to-be-tested wafer can be determined more accurately, and the temperature uniformity of the wafer can be improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of semiconductor manufacturing, and particularly relates to a semiconductor process chamber. BACKGROUND

[0002] In the process of processing a wafer, the wafer needs to be heated to reach a required process temperature. Although the current heating of the wafer is realized by setting a halogen lamp or a heating base in a process chamber, according to the processing result of the wafer, the wafer often has a temperature unevenness, which leads to the processing result of the wafer failing to meet the requirements. Although the temperature uniformity of the wafer can be improved by adding a laser device in the process chamber and heating the area with a lower temperature of the wafer by the laser device, how to accurately determine the area of the wafer that needs to be heated is one of the problems to be solved by the person skilled in the art. SUMMARY

[0003] The present application discloses a semiconductor process chamber to accurately determine the area of the wafer that needs to be heated.

[0004] The present application discloses a semiconductor process chamber, which comprises a cavity, a thermal imaging device, a heating device and a control device arranged on the cavity; the thermal imaging device is arranged on the top of the cavity and extends to the inside of the cavity; the inside of the cavity has a wafer carrying device for carrying a wafer to be measured; the thermal imaging device is used for collecting a thermal image of the wafer to be measured; the heating device is used for heating the wafer to be measured; the control device is connected with the thermal imaging device and the heating device; the control device is used for obtaining the thermal image of the wafer to be measured collected by the thermal imaging device, obtaining the temperature value of each pixel point belonging to the wafer to be measured according to the thermal image, dividing the wafer to be measured into multiple areas, determining the temperature value of each area of the wafer to be measured according to the temperature value of each pixel point in each area of the wafer to be measured, determining the area of the wafer to be measured that needs to be heated according to the temperature value of each area of the wafer to be measured, and controlling the heating device to heat the area of the wafer to be measured that needs to be heated.

[0005] In some examples, the controller is configured to perform edge detection on the thermal image to obtain a plurality of coordinate values of the edge of the wafer under test in the thermal image, determine a coordinate value of the center of the wafer under test in the thermal image according to the plurality of coordinate values of the edge of the wafer under test in the thermal image and a corresponding relationship between the coordinate values of the edge and the coordinate values of the center of a template wafer, obtain a coordinate value of each pixel belonging to the wafer under test in the thermal image according to the plurality of coordinate values of the edge and the coordinate value of the center of the wafer under test in the thermal image, obtain a gray scale value of each pixel belonging to the wafer under test in the thermal image according to the coordinate value of each pixel belonging to the wafer under test in the thermal image, and obtain a temperature value of each pixel belonging to the wafer under test in the thermal image according to the gray scale value of each pixel belonging to the wafer under test in the thermal image.

[0006] In some examples, any of the plurality of regions comprises a plurality of sections, and a temperature value of any of the plurality of regions is equal to an average of temperature values of each section in the region, and a temperature value of any section in the region is equal to an average of temperature values of each pixel in the section.

[0007] In some examples, the controller is configured to determine that any of the plurality of regions is a region requiring heating if a difference between a temperature value of the region and an expected temperature value is greater than or equal to a first preset value, and determine whether a temperature value tolerance of each section in the region is greater than or equal to a second preset value if the difference between the temperature value of the region and the expected temperature value is less than the first preset value, and determine that the region is the region requiring heating if the temperature value tolerance of any section in the region is greater than or equal to the second preset value.

[0008] In some examples, the plurality of regions comprises a plurality of annular regions with different radii.

[0009] In some examples, the controller is further configured to, after determining the region requiring heating, repeatedly perform the steps of dividing the region requiring heating into a plurality of regions and determining a region requiring heating in the plurality of regions until a smallest region requiring heating is determined.

[0010] In some examples, the heating device comprises a whole heating device and a local heating device; the whole heating device comprises a heating device arranged inside the wafer supporting device; the whole heating device is configured to heat the wafer to be tested as a whole; the local heating device comprises a laser heating device arranged on the top of the cavity, and the laser emitted by the laser heating device can irradiate on a part of the wafer to be tested; the local heating device is configured to heat the wafer to be tested locally; the control device is configured to control the whole heating device to heat the wafer to be tested when all regions of the wafer to be tested need to be heated, and control the local heating device to heat the wafer to be tested when part of the wafer to be tested needs to be heated.

[0011] In some examples, the local heating device further comprises a positioning component arranged on the top of the cavity, and the positioning component is configured to drive the light spot of the laser heating device to move; the control device is further configured to control the positioning component to move the light spot of the laser heating device to the region that needs to be heated, and control the laser heating device to heat the region that needs to be heated.

[0012] In some examples, the positioning component comprises a rotating platform with a through hole, and the laser heating device is arranged in the through hole of the rotating platform at a preset inclined angle; the laser emitted by the laser heating device passes through the through hole and irradiates on the wafer to be tested inside the cavity; and the light spot of the laser heating device moves towards or away from the center of the wafer to be tested as the rotating platform rotates.

[0013] In some examples, the control device is further configured to determine the output power of the laser heating device according to the temperature value and the expected temperature value of the region that needs to be heated of the wafer to be tested, and control the laser heating device to heat the region that needs to be heated at the output power.

[0014] The semiconductor process chamber disclosed in the application comprises a cavity and a thermal imaging device, a heating device and a control device arranged on the cavity, the thermal imaging device is arranged on the top of the cavity and extends to the inside of the cavity, the inside of the cavity has a wafer bearing device for bearing a wafer to be measured, the thermal imaging device is used for collecting a thermal image of the wafer to be measured, the heating device is used for heating the wafer to be measured, the control device is connected with the thermal imaging device and the heating device, the control device is used for obtaining the thermal image of the wafer to be measured collected by the thermal imaging device, obtaining the temperature value of each pixel point belonging to the wafer to be measured according to the thermal image, dividing the wafer to be measured into multiple regions, determining the temperature value of each region of the wafer to be measured according to the temperature value of each pixel point in each region of the wafer to be measured, determining the region needing to be heated of the wafer to be measured according to the temperature value of each region of the wafer to be measured, and controlling the heating device to heat the region needing to be heated of the wafer to be measured, so that the region needing to be heated of the wafer to be measured can be more accurately determined through the thermal image of the wafer to be measured collected by the thermal imaging device, and then the region needing to be heated of the wafer to be measured can be heated by the heating device, so that the uniformity of the wafer temperature can be improved. BRIEF DESCRIPTION OF DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the application or the background art, the following will describe the drawings needed to be used in the embodiments of the application or the background art.

[0016] Figure 1 A structural schematic diagram of a semiconductor process chamber disclosed in the embodiments of the application.

[0017] Figure 2 A pixel distribution schematic diagram of a thermal imaging device disclosed in the embodiments of the application.

[0018] Figure 3 A schematic diagram of a region division mode of a wafer to be measured disclosed in the embodiments of the application.

[0019] Figure 4 A schematic diagram of a division mode in a temperature value calculation method of a wafer to be measured disclosed in the embodiments of the application. DETAILED DESCRIPTION

[0020] The technical solutions in the embodiments of the application will be described clearly and completely in combination with the drawings in the embodiments of the application. Obviously, the described embodiments are only a part of the embodiments of the application, not all the embodiments of the application. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative labor are within the protection scope of the application.

[0021] Currently, the temperature measuring device of the process chamber is mainly a pyrometer. The pyrometer can measure the temperature in the process chamber, so that the overall temperature of the wafer can be determined according to the measurement result of the pyrometer, and the overall temperature of the wafer can be adjusted by adjusting the output power of the halogen lamp or the heater in the wafer support device.

[0022] Although the temperature of the wafer can also be measured by the pyrometer, because the pyrometer can only measure the temperature of one point, that is, the temperature of a local area of the wafer, the temperature measurement result of the pyrometer cannot accurately determine the non-uniformity of the temperature of the wafer, and cannot accurately determine the area of the wafer that needs to be heated.

[0023] Currently, the area of the wafer that needs to be heated is determined based on the last wafer processing result. However, because there are slight differences in the processing technology of the wafer each time, the area of the wafer that needs to be heated cannot be accurately determined by using the last wafer processing result.

[0024] Therefore, the present application discloses a temperature control scheme. The thermal imager is used to collect the thermal image of the wafer, and the temperature of each area of the wafer is determined according to the thermal image, so that the area of the wafer that needs to be heated can be accurately determined.

[0025] As an optional implementation of the present application, the present application discloses a semiconductor process chamber, as shown in the figure, which comprises a cavity 1 and a thermal imager 10, a heating device 20 and a control device (not shown in the figure) arranged on the cavity 1. The control device is connected to the thermal imager 10 and the heating device 20. Figure 1

[0026] The thermal imager 10 is arranged at the top of the cavity 1 and extends to the inside of the cavity 1. The inside of the cavity 1 has a wafer support device for supporting the wafer to be measured 11. The thermal imager 10 is used to collect the thermal image of the wafer to be measured 11. The control device is used to obtain the thermal image of the wafer to be measured collected by the thermal imager 10, obtain the temperature value of each pixel point belonging to the wafer to be measured according to the thermal image, divide the wafer to be measured into multiple areas, determine the temperature value of each area of the wafer to be measured according to the temperature value of each pixel point in each area of the wafer to be measured, determine the area of the wafer to be measured that needs to be heated according to the temperature value of each area of the wafer to be measured, and control the heating device 20 to heat the area of the wafer to be measured that needs to be heated.

[0027] In the present application, the wafer to be measured 11 includes a wafer being processed. Specifically, the wafer to be measured 11 can be a wafer being processed by deposition, etching or other processing technology, and the processing technology needs to heat the wafer.

[0028] ​In the embodiment of the present application, the thermal imaging device 10 can be an infrared thermal imaging device or an ultraviolet thermal imaging device, etc. As shown in Figure 1 The thermal imaging device 10 can be installed on the upper partition 13 of the cavity 1 by means of the mounting flange 12. The imaging surface of the thermal imaging device 10 faces the wafer 11 to be measured, and the imaging area of the thermal imaging device 10 covers the entire wafer 11 to be measured, so that the thermal image of the entire wafer 11 to be measured can be acquired by the thermal imaging device 10.

[0029] It should be noted that the cavity 1 can also have an upper pyrometer for calibrating the temperature of the process chamber, but because the upper pyrometer is only used during equipment debugging, in some embodiments of the present application, the thermal imaging device 10 can replace the upper pyrometer. That is, the thermal imaging device 10 can be arranged at the position of the upper pyrometer, based on which, not only the area of the wafer 11 to be measured that needs to be heated can be determined based on the thermal image acquired by the thermal imaging device 10, but also the equipment can be debugged based on the thermal image acquired by the thermal imaging device 10, etc.

[0030] In the embodiment of the present application, the control device can be a programmable logic controller (PLC) or the like, so as to improve the real-time performance and response speed of the control device.

[0031] Because the thermal imaging device 10 can simultaneously acquire the thermal images of various areas of the wafer 11 to be measured, the area of the wafer 11 to be measured that needs to be heated can be more accurately determined based on the thermal image of the wafer 11 to be measured, and then the area of the wafer 11 to be measured that needs to be heated can be heated by the heating device 20, so as to improve the uniformity of the temperature of the wafer 11 to be measured.

[0032] Taking the case that the thermal imaging device 10 is an infrared thermal imaging device as an example, the infrared thermal imaging device can acquire the thermal radiation energy of the wafer 11 to be measured by collecting the infrared light emitted by the wafer 11 to be measured, and convert the thermal radiation energy into a gray scale value, and then image by means of the difference in the gray scale value. That is, the control device can acquire the gray scale value of each pixel point in the thermal image of the wafer 11 to be measured based on the thermal image of the wafer 11 to be measured acquired by the thermal imaging device 10, and then acquire the temperature value of each pixel point in the area where the wafer 11 to be measured is located based on the gray scale value of each pixel point in the area where the wafer 11 to be measured is located.

[0033] It can be understood that, as Figure 2As shown, the thermal image is an image composed of a plurality of pixel points 22, and the plurality of pixel points 22 are arranged in an array. The position of any pixel point 22 in the pixel array is the coordinate value of the pixel point 22, and any pixel point 22 has a gray scale value. The temperature value of any pixel point 22 can be calculated according to the gray scale value of the pixel point 22. Based on this, the control device can obtain the temperature value Bij and the coordinate value Aij of each pixel point 22 according to the thermal image. After the control device screens each pixel point 22 belonging to the wafer under test 11 from the thermal image, the temperature value of each pixel point 22 belonging to the wafer under test 11 can be obtained.

[0034] In some embodiments of the present application, the wafer carrying device drives the wafer under test 11 to rotate around its center, and the brightness of the thermal image of the wafer under test 11 changes with the temperature change in the process chamber during rotation. Based on this, the control device can perform real-time edge detection and center positioning of the wafer under test according to the thermal image of the wafer under test 11, to obtain the coordinate values of each pixel point belonging to the wafer under test 11 in the thermal image, and further obtain the temperature values of each pixel point belonging to the wafer under test 11 in the thermal image.

[0035] However, because this method has very high real-time requirements and high performance requirements for the control device, in some other embodiments, in order to reduce the amount of calculation and the occupancy rate of the performance of the control device, a template matching method is used to obtain the coordinate values of each pixel point belonging to the wafer under test in the thermal image, in combination with the characteristics of a single scene and good repeatability of the process chamber.

[0036] In some embodiments of the present application, the control device is used for edge detection of the thermal image to obtain a plurality of coordinate values of the edge of the wafer under test in the thermal image, to determine the coordinate value of the center of the wafer under test in the thermal image according to the corresponding relationship between the edge coordinate value and the center coordinate value of the template wafer, to obtain the coordinate values of each pixel point belonging to the wafer under test in the thermal image according to the plurality of coordinate values of the edge of the wafer under test and the coordinate value of the center in the thermal image, to obtain the gray scale values of each pixel point belonging to the wafer under test in the thermal image according to the coordinate values of each pixel point belonging to the wafer under test in the thermal image, and to obtain the temperature values of each pixel point belonging to the wafer under test in the thermal image according to the gray scale values of each pixel point belonging to the wafer under test in the thermal image.

[0037] Because the positions of the wafer carrying device and the thermal imaging device 10 are fixed, the position of the wafer in the thermal image is fixed during the processing of the wafer, so that the definition of the template wafer template can be completed in advance according to the size of the thermal image and the template wafer. That is, the center coordinate range (x0+△x, y0+△y) of the template wafer, the edge coordinate range ((x0+△x)*cosθ*R, (y0+△y)*sinθ*R) of the template wafer, and the coordinate value range A of each point in the area between the center and the edge of the template wafer can be obtained in advance xy模板 . Wherein, R is the radius of the wafer, θ is the angle between the line connecting the point at the edge coordinate of the wafer and the center and the abscissa, (x0, y0) is the ideal center coordinate of the wafer, (x0+△x, y0+△y) is the center coordinate of the wafer with a certain deviation, and the values of the deviations △x and △y can be set according to the actual situation, which will not be described here. Based on this, the template obtained by actual measurement is more accurate, and the edge detection of the template wafer is reduced, the computational burden of the controller is reduced, and the utilization rate of the process chamber application scenario is improved.

[0038] After the definition of the template wafer template is completed in advance, the edge of the thermal image of the wafer to be measured 11 is detected to obtain the coordinate values of a plurality of pixel points at the edge of the wafer to be measured in the thermal image. Assuming that the vertical edge operator is G x0 , the horizontal edge operator is G y0 , the convolution calculation of the thermal image based on the vertical edge operator G x0 and the horizontal edge operator G y0 obtains G x , G y , and then the edge intensity G is calculated. Wherein, G x represents the vertical edge intensity of any pixel point at the edge of the wafer to be measured in the thermal image, G y represents the horizontal edge intensity of any pixel point at the edge of the wafer to be measured in the thermal image, G x0 ={(1 0),(0-1)}; G y0 ={(01),(-1 0)}; G=sqrt(G x 2 +G y 2 ). Wherein, the convolution of each pixel point at θ=0°, 90°, 180°, 270° of the edge of the wafer to be measured in the thermal image can be calculated in priority.

[0039] Because the process is highly repetitive, the edge detection criteria is increased with the template edge coordinate weight. The higher the edge strength G and the closer to the template edge coordinate, the more likely the pixel point is the edge pixel point of the wafer under test in the thermal image. The judgment weight of the edge strength G is greater than the template edge coordinate weight. Finally, the coordinates of the multiple pixel points of the wafer under test in the thermal image are obtained {(x1, y1), (x2, y2),...}.

[0040] It should be noted that when the thermal image cannot detect the wafer edge or the calculation result conflicts, the value of θ in the edge coordinate formula (x0+△x)*cosθ*R and (y0+△y)*sinθ*R can be relaxed, and the calculation is performed again. However, if the wafer edge cannot be detected, the process is further relaxed to allow the coordinate deviation range (△x, △y) until all pixel points in the thermal image are detected globally. If the wafer edge cannot be detected or the calculation result conflicts, it is considered that the wafer under test is not in the placement position range of the process chamber, and a slip sheet alarm is issued. Based on this, by narrowing the initial coordinates and expanding the coordinate range step by step when the detection is unsuccessful, the edge detection time can be greatly reduced, and the real-time performance of the system can be improved. In addition, the template edge coordinate weight is added to the judgment criteria, which increases the robustness and accuracy of the judgment.

[0041] It should be noted that after the controller obtains the coordinate values of the multiple pixel points of the wafer under test at the edge in the thermal image, the incorrect coordinate values and the mutually contradictory coordinate values need to be removed, and the correct coordinate values need to be selected. In order to improve the robustness and accuracy of the matching, first, the thermal image of the wafer under test and the thermal image of the template wafer are normalized. Specifically, the average value of the coordinate values A xy of the pixel points in the region of the wafer under test is calculated to obtain A xy平均 , and then A xy -A xy平均 is calculated for each pixel point to obtain A xy零均 , and zero mean processing is completed to reduce the influence of image brightness changes. A xy零均 is averaged again to obtain A xy零均平均 , and then the standard deviation A xy零均 between A xy零均平均 and A xy零均标准差 is calculated, and A xy零均 is divided by A xy零均标准差 to obtain A xy归一 , and the normalization processing is completed.

[0042] For the coordinate value of each pixel point at the edge of the wafer under test in the thermal image, the trusted region ROI 待测 , ROI 模板. A xy归一 The correlation number R between the two is calculated, and the greater the correlation number R, the more the coordinate value of the pixel point is considered to be the actual coordinate of the wafer in the thermal image. Then, the edge correlation number weights in the four directions of the upper left, lower left, upper right, and lower right are increased from the coordinate values of the numerous edge pixel points, and the coordinate value of the pixel point with the greatest correlation number in the four directions is selected as the coordinate value of the pixel point at the edge of the wafer in the thermal image. Here, R = Sum(A 匹配归一 -A 匹配归一平均 )*Sum(A 模板归一 -A 建模归一平均 ) / (Std(A 匹配归一 )*Std(A 模板归一 )). Based on this, the influence of the brightness change of the wafer under test during heating can be effectively reduced, and the center offset and local distortion caused by rotation can also be alleviated to a certain extent.

[0043] After the control device obtains the multiple coordinate values of the edge of the wafer under test in the thermal image, the coordinate value of the center of the wafer under test in the thermal image can be determined according to the corresponding relationship between the multiple coordinate values of the edge of the wafer under test in the thermal image and the edge coordinate value and the center coordinate value of the template wafer. Then, the coordinate values of each pixel point belonging to the wafer under test in the thermal image can be obtained according to the multiple coordinate values of the edge of the wafer under test in the thermal image and the coordinate value of the center of the wafer under test.

[0044] In some embodiments, the control device can calculate the coordinate values of each pixel point located at different radii in the thermal image according to the coordinate value of the center of the wafer under test in the thermal image and the radius. Of course, the present application is not limited thereto, and in other embodiments, the control device can also filter out each pixel point located at different radii from each pixel point in the thermal image according to the coordinate value of the center of the wafer under test in the thermal image and the radius, and obtain the coordinate values of each pixel point located at different radii in the thermal image.

[0045] Since each pixel point has a coordinate value and a corresponding gray scale value, the gray scale values of each pixel point of the wafer under test in the thermal image can be obtained according to the coordinate values of each pixel point of the wafer under test in the thermal image, and the temperature values of each pixel point of the wafer under test in the thermal image can be obtained according to the gray scale values of each pixel point of the wafer under test in the thermal image.

[0046] As mentioned above, after the control device obtains the temperature value of each pixel point of the wafer to be tested in the thermal image, it can obtain the temperature value of each pixel point in each area of ​​the wafer to be tested in the thermal image, and then determine the temperature value of each area of ​​the wafer to be tested 11 according to the temperature value of each pixel point in each area of ​​the wafer to be tested in the thermal image. According to the temperature value of each area of ​​the wafer to be tested 11, determine the area of ​​the wafer to be tested 11 that needs to be heated, and control the heating device to heat the area of ​​the wafer to be tested 11 that needs to be heated.

[0047] In some embodiments of the present invention, the multiple regions of the wafer 11 to be tested include multiple annular regions with different radii, such as Figure 3 As shown, the control device can evenly divide the wafer 11 under test into a plurality of annular regions of different radii, such as S1 to Sn, where n is an integer greater than or equal to 2. Of course, the present invention is not limited thereto. In other embodiments, the regions can be divided according to the heating requirements of the wafer 11 under test, which will not be described in detail here.

[0048] On this basis, in some embodiments, such as Figure 4 As shown, the control device can divide each area of ​​the wafer to be tested 11, such as the annular area, into multiple segments, for example, into multiple segments P1 to P8, and then obtain the average temperature value of each segment based on the temperature value of each pixel point in each segment, and then obtain the temperature value of each area based on the average value of the average temperature value of each segment in each area. In other words, the temperature value of any area of ​​the wafer to be tested is equal to the average temperature value of each segment in the area, and the temperature value of any segment is equal to the average temperature value of each pixel point in the segment. Of course, the present invention is not limited to this. In other embodiments, the temperature value of any area of ​​the wafer to be tested can be equal to the average temperature value of each pixel point in the area, which will not be repeated here.

[0049] It should be noted that the width of each annular area can be adjusted as needed. However, when the heating device is a laser device, the width cannot be smaller than the width affected by laser thermal radiation and heat conduction.

[0050] In some embodiments, after the control device obtains the temperature values ​​of various areas of the wafer 11 to be tested, it can not only compare the temperature values ​​of various areas of the wafer 11 to be tested with each other to determine the areas of the wafer 11 to be tested that need to be heated, but also compare the temperature values ​​of various areas of the wafer 11 to be tested with the expected temperature values ​​of various areas of the wafer 11 to be tested to determine the areas of the wafer 11 to be tested that need to be heated.

[0051] That is, the control device can determine that any region of the wafer under test 11 is a region requiring heating if the temperature value of the region is much lower than the temperature values of other regions, or if the temperature value of any region of the wafer under test 11 is much lower than the expected temperature value, or if the temperature values of all regions of the wafer under test 11 are much lower than the expected temperature value.

[0052] In some embodiments, the control device can also determine the region requiring heating by comparing each region with each other and with the expected temperature value. Specifically, the control device can determine that any region of the wafer under test 11 is a region requiring heating if the difference between the temperature value of the region and the expected temperature value is greater than or equal to a first preset value, or if the temperature value tolerance of any section of the region is greater than or equal to a second preset value when the difference between the temperature value of the region and the expected temperature value is less than the first preset value. The first preset value and the second preset value can be set according to actual conditions. In addition, the temperature value tolerance of each section can be calculated when calculating the average temperature value of each section.

[0053] It should be noted that the control device can determine the region requiring heating in multiple cycles. That is, the control device is further configured to, after determining the region requiring heating, repeatedly divide the region requiring heating into multiple regions and determine the region requiring heating in the multiple regions until the smallest region requiring heating is determined.

[0054] Specifically, the control device can first divide each region into multiple regions with a larger width, and after determining the region requiring heating, the region requiring heating can be divided into multiple regions with a smaller width in order to refine the region, and the temperature of the region is calculated to determine a more refined region requiring heating, and the more refined region requiring heating is further divided until the smallest region requiring heating is determined. Based on this, the case that the maximum temperature difference is just in the middle of two regions can be well avoided, and the connection problem of each region is avoided. In the calculation process, the larger width region is searched first, and then the smaller region of the larger width region is searched, which will reduce the algorithm operation amount, improve the operation speed, and improve the real-time performance.

[0055] On this basis, in some embodiments of the present application, the heating device 20 comprises a whole heating device (not shown in the figure) and a local heating device. The whole heating device comprises a heating device arranged inside the wafer carrying device or a halogen lamp arranged inside the cavity. The whole heating device is used to heat the wafer to be measured as a whole.

[0056] As shown in the figure, the local heating device comprises a laser heating device 201 arranged on the top of the cavity 1, and the like. The laser emitted by the laser heating device 201 can irradiate on a part of the wafer to be measured 11. The local heating device is used to heat the wafer to be measured locally. Of course, the present application is not limited to this. In other embodiments, the local heating device can also be a halogen lamp or an LED lamp with a light converging device, and the like, which will not be described here. Figure 1

[0057] The control device is used to control the whole heating device to heat the area of the wafer to be measured 11 which needs to be heated when all the areas of the wafer to be measured 11 need to be heated, and control the local heating device such as the laser heating device 201 to heat the area of the wafer to be measured 11 which needs to be heated when only part of the area of the wafer to be measured 11 needs to be heated.

[0058] In some embodiments of the present application, as shown in the figure, the local heating device further comprises a positioning component 202. The positioning component 202 is installed on the top of the cavity 1. The positioning component 202 is used to drive the light spot of the laser heating device 201 to move. The control device is further used to control the positioning component 202 to move the light spot of the laser heating device 201 to the area which needs to be heated, and control the laser heating device 201 to heat the area which needs to be heated by laser. Figure 1 As shown in the figure, the positioning component 202 comprises a rotating platform with a through hole. The rotating platform is installed on the upper partition plate 13 on the top of the cavity 1 through a mounting flange. The laser heating device 201 is installed in the through hole of the rotating platform at a preset inclined angle. The laser emitted by the laser heating device 201 transmits through the through hole and irradiates on the wafer to be measured 11 inside the cavity 1. The light spot of the laser heating device 201 moves towards the center of the wafer to be measured 11 or away from the center of the wafer to be measured 11 with the rotation of the rotating platform. Because the wafer carrying device can drive the wafer to be measured 11 to rotate around its center, the positioning component 202 drives the light spot of the laser heating device 201 to move towards the center of the wafer to be measured 11 or away from the center of the wafer to be measured 11, so that the light spot of the laser heating device 201 can irradiate on each area of the wafer to be measured 11. The positioning component 202 moves and stops the light spot of the laser heating device 201 on the area which needs to be heated, so as to realize the laser heating of the area which needs to be heated.

[0059] Figure 1

[0060] ​​​On this basis, in some embodiments of the present application, the control device is further configured to determine the output power of the laser heating device 201 according to the temperature value and the expected temperature value of the region of the wafer 11 to be heated, and control the laser heating device 201 to heat the region to be heated with the output power.

[0061] Based on this, the real-time closed-loop control of the laser heating device 201 can be realized according to the thermal imaging device 10. Not only can the temperature value of the region of the wafer 11 to be heated be more accurately obtained according to the thermal image, but also the temperature rise amplitude can be more accurately determined according to the temperature value and the expected temperature value of the region to be heated, and then the output power of the laser heating device 201 can be more accurately determined according to the temperature rise amplitude, and then the temperature of the region after heating can be closer to the expected temperature value.

[0062] Compared with the current method of determining the temperature rise amplitude of the region to be heated according to the experience of process personnel, and then determining the output power of the laser heating device 201 according to the temperature rise amplitude, the accuracy is higher, and the temperature rise amplitude of the region to be heated does not need to be obtained by summarizing experience through multiple processes, which simplifies the process flow, reduces the process difficulty, and improves the process efficiency. Moreover, it is no longer dependent on the repeatability and consistency of the equipment, and as long as the expected temperature is set correctly, a better process result can be obtained.

[0063] The technical features of the above embodiments can be combined in any way. To make the description concise, not all possible combinations of the technical features in the above embodiments are described, but as long as the combinations of the technical features do not exist contradictory, they should be considered as the scope of the present application.

[0064] The above embodiments only express several implementation manners of the present application, and the description is specific and detailed, but it should not be understood as a limitation on the scope of the patent. It should be pointed out that for ordinary skilled in the art, without departing from the concept of the present application, some modifications and improvements can be made, which are all within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the appended claims.

Claims

1. A semiconductor process chamber, comprising: The cavity and a thermal imaging device, a heating device and a control device arranged on the cavity; The thermal imaging device is arranged on the top of the cavity and extends to the inside of the cavity; the inside of the cavity has a wafer carrying device for carrying a wafer to be measured; the thermal imaging device is used to collect a thermal image of the wafer to be measured; The heating device is used to heat the wafer to be measured; The control device is connected with the thermal imaging device and the heating device, and is used to acquire the thermal image of the wafer to be measured collected by the thermal imaging device, obtain temperature values of each pixel point belonging to the wafer to be measured according to the thermal image, divide the wafer to be measured into multiple regions, determine temperature values of each region of the wafer to be measured according to the temperature values of each pixel point in each region of the wafer to be measured, determine a region needing to be heated of the wafer to be measured according to the temperature values of each region of the wafer to be measured, and control the heating device to heat the region needing to be heated of the wafer to be measured.

2. The semiconductor process chamber of claim 1, wherein, The control device is used to perform edge detection on the thermal image, obtain multiple coordinate values of the edge of the wafer to be measured in the thermal image, determine coordinate values of the center of the wafer to be measured in the thermal image according to the multiple coordinate values of the edge of the wafer to be measured in the thermal image and a corresponding relationship between edge coordinate values and center coordinate values of a template wafer, obtain coordinate values of each pixel point belonging to the wafer to be measured in the thermal image according to the multiple coordinate values of the edge of the wafer to be measured and the coordinate values of the center in the thermal image, obtain gray scale values of each pixel point belonging to the wafer to be measured in the thermal image according to the coordinate values of each pixel point belonging to the wafer to be measured in the thermal image, and obtain temperature values of each pixel point belonging to the wafer to be measured in the thermal image according to the gray scale values of each pixel point belonging to the wafer to be measured in the thermal image.

3. The semiconductor process chamber of claim 1, wherein, Any region of the multiple regions includes multiple sections, and the temperature value of any region of the multiple regions is equal to an average value of temperature values of each section in the region, and the temperature value of any section in the region is equal to an average value of temperature values of each pixel point in the section.

4. The semiconductor process chamber of claim 1 or 3, wherein, The control device is used to determine that the region is a region needing to be heated when a difference between the temperature value of any region of the multiple regions and an expected temperature value is greater than or equal to a first preset value, and determine whether a temperature value tolerance of each section of the region is greater than or equal to a second preset value when the difference between the temperature value of any region of the multiple regions and the expected temperature value is less than the first preset value, and determine that the region is a region needing to be heated if the temperature value tolerance of any section in the region is greater than or equal to the second preset value.

5. The semiconductor process chamber of claim 4, wherein, The multiple regions include multiple annular regions with different radii.

6. The semiconductor process chamber of claim 1, wherein, The control device is further used to repeatedly perform the steps of dividing the region needing to be heated into multiple regions and determining a region needing to be heated of the multiple regions until a minimum region needing to be heated is determined after the region needing to be heated is determined.

7. The semiconductor process chamber of claim 1, wherein, The heating device comprises a whole heating device and a local heating device; the whole heating device comprises a heating device arranged inside the wafer supporting device; the whole heating device is used for heating the wafer to be tested as a whole; the local heating device comprises a laser heating device arranged on the top of the cavity, and the laser emitted by the laser heating device can irradiate on a part of the wafer to be tested; the local heating device is used for heating the wafer to be tested locally. The control device is used for controlling the whole heating device to heat the area of the wafer to be tested which needs to be heated when all areas of the wafer to be tested need to be heated, and controlling the local heating device to heat the area of the wafer to be tested which needs to be heated when part of the area of the wafer to be tested needs to be heated.

8. The semiconductor process chamber of claim 7, wherein, The local heating device further comprises a positioning component, the positioning component is arranged on the top of the cavity, and the positioning component is used for driving the light spot of the laser heating device to move; The control device is further used for controlling the positioning component to move the light spot of the laser heating device to the area which needs to be heated, and controlling the laser heating device to heat the area which needs to be heated by laser.

9. The semiconductor process chamber of claim 8, wherein, The positioning component comprises a rotating platform with a through hole, the laser heating device is arranged in the through hole of the rotating platform at a preset inclined angle, the laser emitted by the laser heating device passes through the through hole and irradiates on the wafer to be tested inside the cavity, and the light spot of the laser heating device moves towards the center of the wafer to be tested or away from the center of the wafer to be tested with the rotation of the rotating platform.

10. The semiconductor process chamber of claim 7, wherein, The control device is further used for determining the output power of the laser heating device according to the temperature value and the expected temperature value of the area of the wafer to be tested which needs to be heated, and controlling the laser heating device to heat the area which needs to be heated by laser at the output power.

Images