Base processing method, base, and semiconductor device process chamber

Abstract

The present invention discloses a method for machining a pedestal, a pedestal, and a process chamber of a semiconductor device. The method for machining the pedestal includes providing a process chamber and a measuring device, in which opening reference information and depth reference information of a recessed structure are pre-stored. Controlling an optical ranging device to emit a ranging light beam to the bottom surface of a specific groove of a rotating pedestal. The optical ranging device sends ranging information to the measuring device according to the ranging optical information, the measuring device calculates the jitter difference of the pedestal, the measuring device obtains a designed depth based on the jitter difference and the depth reference information, such that the designed depth is greater than the jitter difference, obtains designed opening size information according to the opening reference information, and forms a recessed structure in the machining area of the pedestal according to the designed depth and the designed opening size information. Thus, the present invention avoids the influence of pedestal jitter on the ranging and positioning of the recessed structure, ensures that the optical detection device only scans the substrate in the groove, and improves the accuracy of optical measurement of the coating thickness.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor measurement, and particularly relates to a method for processing a base, a base, and a process chamber of a semiconductor device. Background Art

[0002] Chemical vapor deposition is an important method for growing semiconductor materials in a semiconductor device, that is, under appropriate temperature and pressure conditions, a chemical vapor deposition reaction occurs on the surface of a wafer substrate to form a semiconductor material layer. The uniformity of the material layer deposited on the wafer surface is an important index for evaluating its quality. Driving the wafer substrate to rotate by rotating the carrier device for placing the wafer substrate is an important method for improving the uniformity.

[0003] During the growth process of the semiconductor material layer, an optical detection device (such as a spectrometer) emits a detection beam in a specific wavelength range from the semiconductor material layer, and information such as the growth rate of the semiconductor material layer can be obtained using the spectral information of the light in the detected specific wavelength range, thereby providing a reference basis for process control.

[0004] Since the carrier device is in a rotating state during the process, the sampling point of the optical detection device will fall outside the non-carrier area outside the carrier area for accommodating the wafer substrate. The optical information in the non-carrier area will also be included in the subsequent integration calculation by the optical detection device, which will cause the fluorescence signal to be weak or even lost. To solve this problem, the prior art uses a ranging reference object to be set at the edge of the carrier device, and an optical ranging device is used to detect the ranging reference object to obtain position information, and this position information is used to indicate that the detection beam emitted by the optical detection device only scans the carrier area. However, as the rotation speed of the carrier device increases, the jitter of the carrier device becomes more significant, and the deviation of the optical ranging device detecting the ranging reference object becomes more significant, thereby affecting the accuracy of the detection beam emitted by the optical detection device scanning the carrier area, and still causing the fluorescence signal to be weak or even lost. Summary of the Invention

[0005] In view of the above disadvantages of the prior art, the purpose of the present invention is to provide a method for processing a base, a base, and a process chamber of a semiconductor device, so as to reduce or avoid the influence of ranging inaccuracy caused by the jitter caused by the rotation of the carrier device, and improve the accuracy of measurement.

[0006] To achieve the above purpose, the present invention provides a method for processing a base, including:

[0007] S0: Provide a process chamber and a measurement device. A base is arranged in the process chamber. The base is provided with a rotation driving device. A groove is arranged on the bearing surface of the base to carry a substrate. The process chamber is provided with an optical distance measurement device opposite to the bearing surface of the base. The measurement device is communicatively connected to the rotation driving device and the optical distance measurement device respectively, so as to measure the dimensional information of a recessed structure preset on the bearing surface of the base. The opening reference information and depth reference information of the recessed structure are pre-stored in the measurement device;

[0008] S1: Control the optical distance measurement device to emit a distance measurement light beam to the bottom surface of a specific groove of the base, and control the rotation driving device to drive the base to rotate;

[0009] S2: The optical distance measurement device acquires distance measurement optical information and sends the distance measurement information of the specific groove to the measurement device according to the acquired distance measurement optical information. The measurement device calculates the jitter difference of the base according to the distance measurement information;

[0010] S3: The measurement device obtains the designed depth according to the jitter difference and the depth reference information, makes the designed depth greater than the jitter difference, and obtains the designed opening size information according to the opening reference information;

[0011] S4: Form a recessed structure in the processing area of the base as a distance measurement indication mark according to the designed depth and the designed opening size information. The processing area of the base is other areas except the area where the groove is located.

[0012] Optionally, the process chamber is further provided with a heating device. In step S1, it further includes:

[0013] Control the process chamber to reach the process temperature through the heating device, and the process temperature is not lower than 700 degrees Celsius.

[0014] Optionally, the distance measurement information includes a minimum distance measurement value and a maximum distance measurement value. In step S2, the step in which the measurement device calculates the jitter difference of the base according to the distance measurement information includes:

[0015] The measurement device calculates the difference between the minimum distance measurement value and the maximum distance measurement value to obtain the jitter difference.

[0016] Optionally, the depth reference information includes a split disc threshold and the bottom surface processing accuracy value of a specific groove. In step S3, the step in which the measurement device obtains the designed depth according to the jitter difference and the depth reference information includes:

[0017] After the measurement device determines that the sum of the jitter difference and the bottom surface processing accuracy value is less than the split disc threshold, it takes the value that is greater than the sum of the jitter difference and the bottom surface processing accuracy value and less than the split disc threshold as the designed depth.

[0018] Optionally, the bearing surface of the base includes a central region and a bearing region surrounding the central region. The number of grooves is at least two, and they are provided in the bearing region. In step S4, the step of forming a recessed structure in the machining area of the base according to the design depth and the design opening size information includes:

[0019] Forming a recessed structure in the area between adjacent grooves in the bearing region, or forming a recessed structure in the central region.

[0020] Optionally, the adjacent grooves include a first groove and a second groove. The spaced area between the first groove and the second groove is the first spaced area, and the spaced area near the second groove and located in the bearing region is the second spaced area;

[0021] In step S4, it further includes:

[0022] Defining the tangent line extending from the center of the central region towards the first spaced area and tangent to the first groove as the first tangent line, and the tangent line extending from the center of the central region towards the second spaced area and tangent to the second groove as the second tangent line. The enclosed area formed by the first tangent line, the second tangent line and the edge of the central region is used as the machining area of the base.

[0023] Optionally, the adjacent grooves include a first groove and a second groove. The spaced area between the first groove and the second groove is the first spaced area, and the spaced area near the second groove and located in the bearing region is the second spaced area;

[0024] In step S4, it further includes:

[0025] Defining the tangent line extending from the center of the central region towards the first spaced area and tangent to the first groove as the first tangent line, and the tangent line extending from the center of the central region towards the first spaced area and tangent to the second groove as the third tangent line. The recessed structure is arranged in the enclosed area formed by the first tangent line, the third tangent line and the edge of the central region as the machining area of the base.

[0026] Optionally, the edge of the central region is tangent to the edge of each groove.

[0027] Optionally, each groove is evenly distributed around the central axis of the base. In step S4, the step of forming a recessed structure in the machining area of the base according to the design depth and the design opening size information includes:

[0028] Forming at least two recessed structures arranged around the same circumferential direction in the machining area.

[0029] Optionally, the opening reference information includes the spot size of the ranging light beam emitted by the optical ranging device. In step S3, the step of obtaining the design opening size information according to the opening reference information includes:

[0030] Take a value greater than the spot size as the design opening size information.

[0031] Optionally, in step S4, the step of forming a concave structure in the machining area of the base according to the design depth and the design opening size information includes:

[0032] Remove part of the material of the base along the axial direction of the base from the top surface of the machining area to form a concave structure, and make the opening size of the concave structure larger than the bottom size.

[0033] The present invention also provides a base obtained by the above base machining method.

[0034] The present invention also provides a semiconductor device process chamber, including:

[0035] A chamber body;

[0036] A base disposed in the chamber body and obtained by the above base machining method;

[0037] An optical distance measuring device disposed in the chamber body and opposite to the bearing surface of the base;

[0038] An optical detection device disposed in the chamber body and opposite to the bearing surface of the base.

[0039] Optionally, the optical distance measuring device includes a blue light distance measuring device.

[0040] Compared with the prior art, the base machining method, the base, and the semiconductor device process chamber of the present invention at least have the following beneficial effects:

[0041] The purpose of the base machining method of the present invention is to set a concave structure in the non-groove area of the bearing surface of the base as a ranging indication mark. In order to reduce or avoid the adverse impact of the rotational jitter of the base on the ranging positioning through the concave structure, the optical distance measuring device is controlled in step S1 to emit a ranging beam from the bottom surface of a specific groove of the base, the rotation driving device is controlled to drive the base to rotate, the jitter difference of the base is obtained in step S2 according to the ranging information of the specific groove, the design depth is obtained in step S3 according to the jitter difference and the pre-stored depth reference information, the design depth is made greater than the jitter difference, the design opening size information is obtained according to the pre-stored opening reference information, and then a concave structure is formed in the machining area of the base according to the design depth and the design opening size information.

[0042] The base in the present invention is formed by the above base machining method, and the semiconductor device process chamber is applied to the above base machining method and includes the above base, and also has the above technical effects. Description of the Drawings

[0043] Figure 1Schematic structural diagram of the process chamber of the semiconductor device in Embodiment 1 of the present invention;

[0044] Figure 2 Sampling trajectory of the process chamber of the semiconductor device during testing and schematic diagram of opening and closing of the optical detection device in Embodiment 1 of the present invention;

[0045] Figure 3 Flow chart of the steps of the base processing method in Embodiment 2 of the present invention;

[0046] Figure 4 Schematic structural diagram of the bearing surface of the base in an example of Embodiment 2 of the present invention;

[0047] Figure 5 Schematic structural diagram of the bearing surface of the base in another example of Embodiment 2 of the present invention;

[0048] Figure 6 Schematic structural diagram of the bearing surface of the base in yet another example of Embodiment 2 of the present invention;

[0049] Figure 7 Schematic structural diagram of marking a sealed area on the bearing surface of the base in Embodiment 2 of the present invention;

[0050] Figure 8 Schematic structural diagram of marking another sealed area on the bearing surface of the base in Embodiment 2 of the present invention;

[0051] Figure 9 Schematic diagram of marking the position of the concave structure on the bearing surface of the base in an example of Embodiment 2 of the present invention;

[0052] Figure 10 Schematic diagram of marking the position of the concave structure on the bearing surface of the base in another example of Embodiment 2 of the present invention;

[0053] Figure 11 Schematic diagram of marking the position of the concave structure on the bearing surface of the base in yet another example of Embodiment 2 of the present invention;

[0054] Figure 12 Schematic partial cross-sectional structure diagram of the base in an example of Embodiment 2 of the present invention;

[0055] Figure 13 Schematic partial cross-sectional structure diagram of the base in another example of Embodiment 2 of the present invention;

[0056] Figure 14 Schematic partial cross-sectional structure diagram of the base in yet another example of Embodiment 2 of the present invention;

[0057] Figure 15 Voltage-time curve diagram formed by algorithm conversion according to ranging data in an example of Embodiment 2 of the present utility model;

[0058] Figure 16 It is the voltage-time curve graph formed by algorithm conversion according to the ranging data and detection data in an example of Embodiment 2 of the present invention;

[0059] Figure 17 It is the voltage-time curve graph formed by algorithm conversion according to the ranging data and detection data in another example of Embodiment 2 of the present invention;

[0060] Figure 18 It is in an example of Embodiment 2 of the present invention Figure 14 Or the top feature schematic diagram of the ranging jump signal in 15;

[0061] Figure 19 It is in another example of Embodiment 2 of the present invention Figure 14 Or the top feature schematic diagram of the ranging jump signal in 15;

[0062] Figure 20 It is the groove ranging distance-ranging time relationship graph in Embodiment 2 of the present invention.

[0063] List of reference numerals:

[0064] 100 Base

[0065] 101 Middle region

[0066] 1011 Sealed area

[0067] 102 Bearing area

[0068] 1021 Groove

[0069] 1021-1 First groove

[0070] 1021-2 Second groove

[0071] 1022 First interval area

[0072] 1023 Second interval area

[0073] 103 Peripheral area

[0074] 104, 104’ Concave structure

[0075] 1041 First opening structure

[0076] 1042 Second opening structure

[0077] 201 First tangent

[0078] 202 Second tangent

[0079] 203 Third tangent

[0080] 300 Spot

[0081] 400 Optical Distance Measuring Device

[0082] 500 Optical Detection Device

[0083] 600 Rotation Driving Device

[0084] 700 Substrate

[0085] 800 Sampling Trajectory Detailed Implementation Modes

[0086] The following specific embodiments illustrate the implementation modes of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific implementation modes. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this application. It should be noted that, without conflict, the following embodiments and the features in the embodiments can be combined with each other.

[0087] It should be noted that the drawings provided in the embodiments of the present invention only illustrate the basic concept of the present invention in a schematic manner. Although only the components related to the present invention are shown in the drawings, rather than being drawn according to the number, shape, and size of the components in actual implementation, the form, number, and ratio of each component in actual implementation can be changed arbitrarily, and the layout form of its components may also be more complex. The structures, ratios, sizes, etc. shown in the drawings of the specification are only used to cooperate with the content disclosed in the specification for those skilled in the art to understand and read, and are not used to limit the implementation conditions of this application. Therefore, they do not have technical substantive significance. Any modification of the structure, change of the proportional relationship, or adjustment of the size should still fall within the scope that can be covered by the technical content disclosed in this application without affecting the effects that the present invention can produce and the purposes that can be achieved.

[0088] Embodiment 1

[0089] This embodiment provides a process chamber of a semiconductor device. Referring to Figure 1 and 2 , this process chamber of the semiconductor device includes a base 100, an optical distance measuring device 400, and an optical detection device 500 disposed in a chamber body (not marked in the figure).

[0090] Among them, a groove 1021 is provided on the bearing surface of the base 100. The groove 1021 is used to carry the substrate. The optical detection device 500 is disposed in the cavity body (not labeled in the figure) and opposite to the bearing surface of the base 100, so as to emit a detection beam to the area where the groove 1021 is located and receive the information of the corresponding feedback beam. According to the received optical information, the coating thickness on the substrate in the groove can be detected. In order to control the optical detection device 500 to emit a detection beam only to the substrate in the groove, a concave structure is further provided in the non-groove area of the bearing surface of the base 100 as a ranging indication mark.

[0091] The position of the groove 1021 is determined by the position of the concave structure and the relative position relationship between the concave structure and the groove 1021. Furthermore, the optical detection device 500 is controlled to emit a detection beam only to the substrate in the groove. The optical ranging device 400 is disposed in the cavity body and opposite to the bearing surface of the base 100, so as to emit a ranging beam to the concave structure and receive the information of the corresponding feedback beam. When the optical ranging device 400 obtains the jump feature information of the concave structure, the position of the concave structure can be located and determined. Subsequently, it is convenient to locate the position of the groove based on the position of the concave structure, ensuring that the optical detection device 500 is turned on and reflects the detection beam at the position corresponding to the groove.

[0092] Optionally, a rotation driving device 600 is further provided in the process chamber of the semiconductor device. The rotation driving device 600 is drivingly connected to the base 100 and is used to drive the rotation of the base 100 during operation. Optionally, a heating device is further provided in the process chamber of the semiconductor device, and the heating device is used to control the process chamber to reach the process temperature. Optionally, the process temperature is not lower than 700 °C. Optionally, the process chamber of the semiconductor device includes a gas injection device disposed opposite to the bearing surface of the base 100, and process gas is injected into the process chamber through the gas injection device.

[0093] When the process chamber of the semiconductor device is working, the substrates 700 are placed in the grooves 1021 one by one. The base 100 rotates under the action of the driving device 600, and process gas for synthesizing the thin film material is introduced into the process chamber to deposit a thin film material layer on the substrate. Before detecting the thickness of the thin film material layer deposited on the substrate, first, the bearing surface of the base 100 is ranged by the optical ranging device 400. After obtaining the jump feature information of the concave structure 104, the position of the concave structure 104 is determined based on the jump feature information, and the opening and closing of the light outlet of the detection light emitted by the optical detection device 500 are controlled in combination with the relative positions of the concave structure 104, the groove 1021, and the base 100, the information of the detection light sampling trajectory 800, and the rotation speed information, so that the detection light is only turned on when the sampling trajectory 800 passes through the surface of the coated substrate and the corresponding specific wavelength information is obtained.

[0094] When the high-speed bearing device is in a high-temperature environment, for example, when the temperature is above 700 °C, the thermal medium in this environment (such as high-temperature process gas - not limited to source gas, purge gas, carrier gas) will affect the detection light emitted by the optical ranging device 400 and / or the reflected light of the semiconductor material layer, resulting in different data obtained by the optical ranging device 400 for ranging the same position on the base 100 in high-temperature and normal-temperature environments respectively. If the ranging light emitted by the optical ranging device 400 is not selected appropriately, it may be impossible to obtain effective ranging data. To avoid the influence of high temperature on the ranging device, in this embodiment, the optical ranging device 400 selected at a process temperature above 700 °C in the process chamber is a blue-light ranging device. This blue-light ranging device is used to emit a blue-light ranging beam towards the concave structure 104 to range the concave structure 104, which can avoid the influence of high temperature on ranging accuracy and improve the accuracy of testing.

[0095] Since the height feature at the concave structure 104 has a significant jump compared with the height features of other surfaces of the ranging sampling trajectory, there is an obvious voltage jump on the voltage-time curve output by the optical ranging device 400. Thus, the position of the concave structure 104 can be determined according to this significant jump feature. However, through the inventor's research, it is found that as the rotation speed of the bearing device increases, the jitter of the bearing device becomes more significant, which will cause the optical ranging device to be more prone to significant deviation in detecting the ranging reference object, affecting the accuracy of the detection beam emitted by the optical detection device in scanning the wafer area, and thus still resulting in weak or even lost fluorescence signals. Therefore, in this embodiment, the shape and depth of the concave structure 104 are set and processed by using the base processing method in Embodiment 2, so as to avoid the influence of the jitter of the bearing device on ranging, improve the ranging accuracy of the concave structure 104, and accurately control the optical detection device to precisely scan the wafer area through the accurate feedback of the position of the concave structure 104 by the optical ranging device 400.

[0096] Embodiment 2

[0097] This embodiment provides a base processing method, which is mainly used to measure the dimensional information of the concave structure, avoid the influence of the base jitter on the positioning of the concave structure, and improve the ranging and positioning accuracy of the concave structure.

[0098] Specifically, referring to Figure 3 , this base processing method includes:

[0099] S0: Provide a process chamber and a measurement device. A pedestal is arranged in the process chamber. The pedestal is provided with a rotation driving device. A groove is arranged on the bearing surface of the pedestal to carry a substrate. The process chamber is provided with an optical distance measurement device opposite to the bearing surface of the pedestal. The measurement device is communicatively connected to the rotation driving device and the optical distance measurement device respectively, so as to measure the dimensional information of a recessed structure preset on the bearing surface of the pedestal. The opening reference information and depth reference information of the recessed structure are pre-stored in the measurement device.

[0100] Referring to Figure 1 and 2 , provide a process chamber, which is the semiconductor device process chamber described in Embodiment 1. A pedestal 100 is arranged in the process chamber. A groove for carrying a substrate is arranged on the bearing surface of the pedestal 100. Process gas is introduced into the process chamber to deposit a material layer on the surface of the substrate. A rotation driving device 600 is arranged at the bottom end of the pedestal 100. The rotation driving device 600 is connected to the pedestal 100 and is used to drive the pedestal 100 to rotate during the material deposition process. An optical distance measurement device 400 opposite to the bearing surface of the pedestal 100 is also arranged in the process chamber. The optical distance measurement device 400 is used to measure the distance from it to the bearing surface of the pedestal 100 to locate the recessed structure subsequently arranged on the bearing surface of the pedestal 100. An optical detection device 500 for detecting the coating thickness of the coated substrate on the bearing surface of the pedestal 100 is also arranged in the process chamber. Subsequently, based on the relative positions of the recessed structure, the groove, and the pedestal 100, the sampling trajectory information of the optical detection device 500, and the rotation speed information, the opening and closing of the light outlet of the detection light emitted by the optical detection device 500 are controlled, so that the detection light starts only when the sampling trajectory passes through the surface of the coated substrate and the corresponding specific wavelength information is obtained.

[0101] Provide a measurement device (not shown in the figure), which is used to measure the depth and opening size of the recessed structure arranged on the pedestal 100. Specifically, the measurement device is communicatively connected to the rotation driving device 600 and the optical distance measurement device 400. The opening reference information and depth reference information of the recessed structure are pre-stored in the measurement device.

[0102] Since the base 100 will generate jitter during rotation, this jitter value will affect the jump characteristic signal when the optical ranging device 400 detects and locates the concave structure. Therefore, when designing the concave structure, it is necessary to first test the jitter difference of the base 100 during normal operation, and design the depth of the concave structure based on the jitter difference. In this embodiment, first, with the base 100 unloaded, the optical ranging device 400 is used to emit a ranging beam to a fixed position on the bottom surface of the groove of the rotating base 100. By changing the temperature of the process chamber or the rotation speed of the base 100, different ranging information is obtained, and the jitter difference of the base 100 is calculated based on the difference of the ranging information. The following steps S1 and S2 are the specific operation steps for obtaining the jitter difference.

[0103] S1: Control the optical ranging device to emit a ranging beam to the bottom surface of the groove of the rotating base, and control the rotation driving device to drive the base to rotate;

[0104] Refer to Figure 1 , control the rotation driving device 600 to drive the base 100 to rotate. During the rotation of the base 100, control the process chamber to reach the process temperature through the heating device, and the process temperature is not lower than 700 degrees Celsius. Inject process gas into the process chamber through the gas injection device. In this operating state where the process chamber is working normally, control the optical ranging device 400 to emit a ranging beam to the bottom surface of the groove 1021 of the base 100. Optionally, the optical ranging device 400 emits a ranging beam in a specific direction to the bottom surface of the groove 1021 of the rotating base 100, for example, it can be a continuously emitted ranging beam or a pulsed emitted ranging beam.

[0105] S2: The optical ranging device obtains ranging optical information and sends the ranging information to the calculation device according to the obtained optical information, and the calculation device calculates the jitter difference of the base based on the ranging information;

[0106] Refer to Figure 1 and 2 , the optical ranging device 400 receives the ranging optical information and sends the ranging information to the calculation device, and the calculation device calculates the jitter difference of the base based on the ranging information. In this embodiment, the ranging information includes the maximum ranging value and the minimum ranging value, and the calculation device calculates the difference between the minimum ranging value and the maximum ranging value to obtain the jitter difference.

[0107] When the substrate carrier device 100 is in a high-temperature environment (e.g., above 700 degrees Celsius), hot gases (e.g., source gas, purge gas, carrier gas) can affect the detection light emitted by the optical ranging device 400 and / or the reflected light of the semiconductor material layer, resulting in deviations in the data obtained by the optical ranging device 400 when measuring the same position on the substrate carrier device 100 at different temperatures. Structural factors such as the backlash fit degree of the reducer of the rotating motor and the stability of the connection between the support shaft and the carrier device will cause the substrate carrier device 100 rotating at high speed to inevitably vibrate. Therefore, it is necessary to conduct ranging tests on the substrate carrier device 100 under process temperature and rotational speed conditions through the optical ranging device 400 to examine the influence of process temperature and rotational speed on ranging, providing a design basis for setting the minimum value of the depth of the recessed structure 104.

[0108] Specifically, the substrate carrier device 100 is a graphite disk covered with a silicon carbide coating, and the optical ranging device 400 is a blue light rangefinder. Set the chamber temperature to different temperatures. After the chamber temperature meets the temperature conditions, control the ranging light of the optical ranging device 400 to vertically exit at the bottom of a groove, and then control the graphite disk to rotate at a certain rotational speed. The optical ranging device 400 (blue light rangefinder) acquires the ranging light and feeds back the ranging data to the host computer. The host computer screens out the ranging data of this groove based on the rotating motor data and the ranging data, obtaining, for example, Figure 20 the distance-time relationship graph shown (the graphite disk rotates at 900 rpm at room temperature). It can be seen from the graph that at high rotational speeds, the ranging values are variable. The specific implementation method for the host computer to screen out the ranging data of this groove based on the rotating motor data and the ranging data is a conventional technical means in the art and will not be elaborated here.

[0109] Control the rotation of the graphite disk at each chamber temperature, position this groove with the assistance of the rotating motor motor signal, and obtain the maximum ranging value and the minimum ranging value of the same position of a specific groove of the same graphite disk under different conditions through the blue light rangefinder. The difference between the maximum ranging value and the minimum ranging value is the vibration difference. The data are shown in Tables 1 and 2 below.

[0110] Table 1

[0111]

[0112] Table 2

[0113]

[0114] As can be seen from Table 1 and Table 2, the influence of temperature and rotational speed on the jitter of the substrate carrier device 100 cannot be ignored, and the depth of the concave structure 104 needs to be greater than the jitter difference value. During the process, since the substrate 700 is placed in the groove 1021, when the substrate carrier device 100 rotates, if the depth of the concave structure 104 is less than or equal to the jitter difference value, due to the jitter of the substrate carrier device 100, the data for measuring the distance to the concave structure 104 is basically the same as or differs too little from the data for measuring the distance to the semiconductor material layer deposited on the substrate 700, making the jump signal of the concave structure 104 not significant.

[0115] S3: The measuring device obtains the designed depth based on the jitter difference value and the depth reference information, and obtains the designed opening size information based on the opening reference information;

[0116] Refer to Figure 4 , the bearing surface of the base 100 includes a central region 101, a bearing region 102 surrounding the central region 101, and an outer region 103 surrounding the bearing region 102. The groove 1021 is provided in the bearing region 102.

[0117] The uneven structure of the bottom surface of the groove 1021 will also cause the measured distance value to show a change in the jitter difference value. This part of the influencing factor also needs to be considered together with the jitter difference value when designing the depth of the concave structure 104. The depth of the concave structure 104 cannot be too deep or penetrate the graphite disk, otherwise it is very easy to cause the graphite disk to crack or there is a risk of cracking during processing. The processing precision value of the bottom surface of the groove 1021 for distance measurement also has a certain influence on the distance measurement of the optical distance measurement device 400. Furthermore, the designed depth of the concave structure 104 is jointly determined by the jitter difference value of the base, the crack threshold, and the processing precision value of the bottom surface of the specific groove 1021. The depth reference information in this embodiment includes the above-mentioned crack threshold and the processing precision value of the bottom surface of the specific groove 1021.

[0118] In this embodiment, when determining the designed depth of the concave structure 104, the measuring device determines whether the sum of the jitter difference value and the bottom surface processing precision is less than the crack threshold. When it is determined to be less than the crack threshold, the value that is greater than the sum of the jitter difference value and the bottom surface processing precision value and less than the crack threshold is used as the designed depth. Optionally, the processing precision value of the bottom surface of the groove 1021 is the absolute value of the maximum processing error value of the height of the bottom surface of the groove 1021. Optionally, the processing precision value of the bottom surface of the groove 1021 is the absolute value of the average processing error value of the height of the bottom surface of the groove 1021.

[0119] In some embodiments, the jitter difference value of the substrate carrier device 100 at the process temperature (1000 degrees Celsius) and rotational speed (1000 rpm) is 0.3 mm, and the absolute value of the maximum processing error of the height of each part of the bottom surface of the groove 1021 is 0.5 mm, then the depth of the concave structure 104 is greater than 0.8 mm.

[0120] In some embodiments, the depth h of the recessed structure 104 is greater than or equal to 1 mm.

[0121] In some embodiments, the depth of the recessed structure 104 does not exceed the disk cracking threshold. For example, when the substrate carrier device 100 is made of graphite with a coating treatment, such as graphite treated with silicon carbide coating. If a recessed structure 104 is formed on such a carrier device with a depth exceeding a certain level, cracks will occur in the substrate carrier device 100. Since graphite has poor wear resistance and is prone to generating graphite powder, it will contaminate the substrate 700 or the semiconductor material layer deposited thereon. In addition, the repeated heating and cooling processes and pressure changes in the process will generate thermal stress on this type of carrier device, which will cause it to be fatigued and damaged and fail due to cracking. Therefore, it is necessary to control the depth of the recessed structure 104 not to exceed the disk cracking threshold. The specific value of the disk cracking threshold is an empirical value, which is jointly determined by the material, shape of the substrate carrier device 100, the thickness of the part where the substrate 700 is carried, the opening size of the recessed structure 104 formed thereon, and the temperature and pressure of the deposition process.

[0122] In some embodiments, the disk cracking threshold value of the recessed structure 104 is taken as the depth of the groove 1021.

[0123] Design opening size information is obtained according to the opening reference information. The opening reference information includes the spot size of the ranging light beam emitted by the optical ranging device, and a value greater than the spot size is taken as the design opening size signal.

[0124] Specifically, the opening size of the recessed structure 104 is configured to allow the beam emitted by the optical ranging device 400 to pass through. Referring to Figure 12 , its radial dimension d is ensured to be able to accommodate the spot 300 emitted by the optical ranging device 400. The recessed structure 104 is recessed from the surface of the substrate carrier device 100 towards the inside of the substrate carrier device 100.

[0125] In some embodiments, referring to Figure 12 , the opening size of the recessed structure 104 is equal to its bottom surface size. For example, the recessed structure 104 can be cylindrical.

[0126] Such as Figure 1 and Figure 2As shown, during the rotation of the substrate carrier device 100, the optical ranging device 400 remains stationary relative to the bearing surface of the substrate carrier device 100, and continuously emits ranging light in a fixed direction towards the bearing surface of the substrate carrier device 100. At this time, the optical ranging device 400 only receives the ranging light information and feeds back the light information to the optical detection device 500 or the main control device (not marked in the figure) of the optical detection device 500. The optical detection device 500 or the main control device (not marked in the figure) of the optical detection device 500 converts the light information into voltage-time relationship data, and forms, through denoising and impurity removal algorithms and fitting algorithms, such as Figure 13 the ranging jump signal shown. Continuing the process, the optical ranging device 400 continuously provides ranging light. The optical detection device 500 or the main control device controlling the optical detection device 500 receives the ranging light information from the optical ranging device 400. The optical detection device 500 or the main control device (not marked in the figure) of the optical detection device 500 will determine the position of the concave structure 104 according to the trigger information formed by the ranging jump signal, and control the detection light emitted by the optical detection device 500 to scan only the surface of the groove 1021 according to the position information of each groove 1021 relative to the concave structure 104, the size information of each groove 1021, and the rotation speed (i.e., Figure 12 the area of "detection light ON" shown), while in the non-groove area, the detection light is controlled to be turned off (i.e., Figure 12 the area of "detection light OFF" shown). The optical detection device 500 or the main control device controlling the optical detection device 500 receives the detection information of the optical detection device 500, and forms, through denoising and impurity removal algorithms and fitting algorithms, such as Figure 14 or the test jump signal and ranging jump signal shown in 15. Among them, Figure 14 and Figure 15 differ in that the position of the concave structure 104 relative to the groove 1021 is different, and the obtained test jump signal and ranging jump signal will overlap or not overlap based on the different relative positions of the concave structure 104 and the groove 1021. It should be noted that the optical detection device 500 or the main control device of the optical detection device 500 determines the moment to turn on or off the detection light according to the position information of each groove 1021 relative to the concave structure 104, the size information of each groove 1021, and the rotation speed, and its specific implementation method is a conventional technical means. The optical detection device 500 or the main control device controlling the optical detection device 500 will further refer to Figure 14 or the graphic information shown in 15 and select to perform an integration algorithm on the graphic area obtained by scanning the semiconductor material layer area to obtain the thickness of the semiconductor material layer.

[0127] In the art, it is well-known that the more complex the algorithms for noise removal and fitting are, the greater the introduced errors will be. Therefore, the opening shape of the recessed structure 104 is further optimized, and the longitudinal profile shape of the recessed structure 104 is adjusted to ensure that the jump signal characteristics generated by scanning it can be significantly distinguished from the jump signal characteristics generated by scanning the semiconductor material layer on the substrate, thereby reducing the algorithm complexity.

[0128] For example, in this embodiment, the shape of the recessed structure 104 is further set such that the opening size is larger than the bottom size, so that the undulation changes of the inner wall of the recessed structure 104 scanned are significantly different from the undulation changes of the surface of the semiconductor material layer scanned. In some embodiments, the opening sizes of the radial profiles of the recessed structure 104 along its recessed direction are non-uniform.

[0129] In one example, referring to Figure 13 , the recessed structure 104 includes a top and a bottom along the recessed direction, and the opening size of the top of the recessed structure 104 is larger than that of the bottom. The recessed structure 104 may be provided with two opening structures, and the recessed structure 104 sequentially includes a first opening structure 1041 and a second opening structure 1042 along the recessed direction, and the opening size of the first opening structure 1041 is larger than that of the second opening structure 1042. The jump signal characteristics formed by the optical ranging device 400 scanning this structure, its top characteristics are as shown in Figure 18 , and can be significantly distinguished from Figure 16 and Figure 17 the top characteristics of the test jump signal shown.

[0130] In another example, referring to Figure 14 , the opening sizes of the radial profiles of the recessed structure 104 along the recessed direction can also be set to gradually decrease. As shown in Figure 14 , the profile of the recessed structure 104 is semi-circular. The jump signal characteristics formed by the optical ranging device 400 scanning this structure, its top characteristics are as shown in Figure 19 , and can also be significantly distinguished from Figure 16 and Figure 17 the top characteristics of the test jump signal shown.

[0131] The depth of the recessed structure 104 cannot be too deep or penetrate the graphite disk, otherwise it is very easy to cause the graphite disk to crack or there is a risk of cracking during processing. The depth of the recessed structure 104 cannot be too shallow, otherwise the jump signal will not be significant due to the insignificant height difference, affecting the control effect. If the depth of the recessed structure 104 is too low, even if designed as shown in Figure 13 and Figure 14In the structure, during the process of process deposition, the concave structure 104 is easily blocked and filled, making it more difficult to distinguish its jump signal from the jump signal formed by the semiconductor material layer, and increasing the difficulty of the corresponding algorithm required.

[0132] S4: Form a concave structure in the processing area of the base as a ranging indication mark according to the designed depth and designed opening size information, where the processing area of the base is the area other than the area where the groove is located.

[0133] Based on step S3, after determining the designed depth information and designed opening size information of the concave structure, form a concave structure in the processing area of the bearing surface of the base as a ranging indication mark. Among them, the processing area of the base is the area other than the area where the groove is located. In this embodiment, the number of grooves 1021 is at least 2 and is provided in the bearing area. Refer to Figure 4 , form a concave structure 104 in the area between adjacent grooves 1021 in the bearing area, refer to Figure 6 , or form a concave structure 104 in the middle area 101, refer to Figure 5 , or form a concave structure 104 in the edge area 103.

[0134] Refer to Figure 1 , when the substrate carrier device 100 rotates under the action of the driving device 600, it is inevitable that the substrate carrier device 100 will vibrate (such as shaking along the radial direction of the substrate carrier device 100). This kind of vibration influence will be more significant with the increase of the rotation speed, and the influence on the edge area of the substrate carrier device 100 is much greater than that on the internal area. Therefore, setting the concave structure 104 in the middle area 101 or in the interval area between adjacent cavities 1021 can reduce or avoid the adverse influence on the accuracy of the ranging data caused by the rotation vibration of the substrate carrier device. Furthermore, in this embodiment, as Figure 4 shown, the concave structure 104 is set in the interval area between adjacent grooves 1021. Or, set in the middle area 101, as Figure 6 shown.

[0135] Since the jump signal of the concave structure 104 requires algorithm processing for noise removal and fitting algorithm processing, the more complex the algorithm, the greater the introduced error. Therefore, further optimizing the position of the concave structure 104 to avoid more overlap between its ranging jump signal and the test jump signal helps to reduce the requirement for algorithm complexity and reduce algorithm error.

[0136] Specifically, refer to Figure 7, two adjacent grooves 1021 are respectively a first groove 1021-1 and a second groove 1021-2, and the interval area between the first groove 1021-1 and the second groove 1021-2 is a first interval area 1022. Refer to Figure 4 , the interval area adjacent to the second groove 1021-2 and adjacent to the first interval area 1022 is a second interval area 1023. Refer to Figure 7 , define the tangent line extending from the center of the middle region 101 towards the first interval area 1022 and tangent to the first groove 1021-1 as the first tangent line 201, and the tangent line extending from the center of the middle region 101 towards the second interval area 1023 and tangent to the second groove 1021-2 as the second tangent line 202. Refer to Figure 8 , define the tangent line extending from the center of the middle region 101 towards the second interval area 1023 and tangent to the second groove 1021-2 as the third tangent line 203.

[0137] In an example, as Figure 7 shown, the concave structure 104 is arranged in the enclosed area 1011 surrounded by the first tangent line 201, the second tangent line 202 and the edge of the middle region 101. The edge of the concave structure 104 is located within the enclosed area 1011 and is not tangent to both the first tangent line 201 and the second tangent line 202 of the enclosed area 1011 at the same time, or as Figure 9 shown, the concave structure 104' is tangent to both the first tangent line 201 and the second tangent line 202 at the same time. During the process, the time period (ranging jump signal) when the optical ranging device 400 scans the concave structure has no intersection with the time period (test jump signal) when the optical detection device 500 scans the nearby groove 1021, as Figure 16 shown; or there is only an intersection at the starting moment and the ending moment, and the repeated time period is less, which further reduces the complexity requirement for the algorithm, thereby reducing the algorithm error and improving the test accuracy.

[0138] In an example, as Figure 8 shown, the concave structure 104 is arranged in the enclosed area 1011 surrounded by the first tangent line 201, the third tangent line 203 and the edge of the middle region 101. The time period when the optical ranging device 400 scans the concave structure (not marked in the figure) only has an intersection with the time period when the optical detection device 500 scans one groove 1021-2, and the complexity requirement for the algorithm is not high, thereby reducing the algorithm error and improving the test accuracy.

[0139] In an example, as Figure 10One of the recessed structures 104' shown in the figure only intersects the first tangent line 201, and the other recessed structure 104' only tangentially contacts the second tangent line 202. Since the recessed structure 104' only intersects either the first tangent line 201 or the second tangent line 202, in this case, the time period during which the optical distance measuring device 400 scans the recessed structure and the time period during which the optical detection device 500 scans the nearby grooves only partially overlap, and the requirement for the complexity of the algorithm is not high. As Figure 11 shown, the recessed structure 104' intersects the first tangent line 201 and the second tangent line 202 respectively. In this case, since the recessed structure 104' is too close to the center and has a large intersection with the time period of the concave cavity, the requirement for the complexity of the algorithm is relatively high.

[0140] The number of the recessed structures 104 can be one or at least two. When the rotation speed of the substrate carrier device 100 is too fast and the sampling speed of the optical distance measuring device 400 is difficult to match, the position of the recessed structure 104 can be assisted in determination by increasing the number of the recessed structures 104.

[0141] In some embodiments, the number of the recessed structures 104 is at least 2, and the two recessed structures 104 are arranged around the same circumferential direction. The grooves 1021 on the substrate carrier device 100 are evenly arranged. In this way, when the sampling of one recessed structure 104 is difficult to match and its jump signal is not significant or even lost, the sampling signals of other recessed structures 104 can be used to replace the sampling signal of this recessed structure 104 for the judgment of the aforementioned voltage-time graph. In some more specific embodiments, the recessed structures 104 are further located on the same circumference formed with the center of the bearing surface as the center of the circle and on the same diameter. In some more specific embodiments, the interval between the 2 recessed structures 104 can be 180°, or the interval between the 3 recessed structures 104 is 120°, or the interval between the 4 recessed structures 104 is 90°.

[0142] Embodiment 3

[0143] This embodiment provides a base, and this base is formed by the base processing method in the above-mentioned Embodiment 2. Since this base is formed by the above-mentioned base processing method, it also has the technical effects of the base processing method in the above-mentioned Embodiment 2.

[0144] The above embodiments only illustratively explain the principles and effects of the present invention, rather than being used to limit the present invention. Any person familiar with this technology can modify or change the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or changes completed by those with ordinary knowledge in the technical field without departing from the spirit and technical ideas disclosed by the present invention should still be covered by the claims of the present invention.

Claims

1. A method for machining a base, characterized in that, Including: S0: Provide a process chamber and a measurement device. A base is arranged in the process chamber. The base is provided with a rotation driving device. A groove is arranged on the bearing surface of the base to bear a substrate. The process chamber is provided with an optical distance measurement device opposite to the bearing surface of the base. The measurement device is respectively in communication connection with the rotation driving device and the optical distance measurement device, and is used for measuring the size information of a concave structure preset on the bearing surface of the base. The opening reference information and the depth reference information of the concave structure are pre-stored in the measurement device. S1: Control the optical distance measurement device to emit a distance measurement light beam to the bottom surface of a specific groove of the base, and control the rotation driving device to drive the base to rotate. S2: The optical distance measurement device acquires distance measurement optical information and sends the distance measurement information of the specific groove to the measurement device according to the acquired distance measurement optical information. The measurement device calculates the jitter difference value of the base according to the distance measurement information. S3: The measurement device obtains a design depth according to the jitter difference value and the depth reference information, makes the design depth greater than the jitter difference value, and obtains design opening size information according to the opening reference information. S4: Form the concave structure in the processing area of the base as a distance measurement indication mark according to the design depth and the design opening size information. The processing area of the base is other areas except the area where the groove is located.

2. The base processing method according to claim 1, characterized in that, The process chamber is further provided with a heating device. In step S1, it further includes: Control the process chamber to reach a process temperature through the heating device, and the process temperature is not lower than 700 degrees Celsius.

3. The base processing method according to claim 1, characterized in that, The distance measurement information includes a minimum distance measurement value and a maximum distance measurement value. In step S2, the step in which the measurement device calculates the jitter difference value of the base according to the distance measurement information includes: The measurement device calculates the difference between the minimum distance measurement value and the maximum distance measurement value to obtain the jitter difference value.

4. The base processing method according to claim 3, characterized in that, The depth reference information includes a crack disc threshold value and the bottom surface processing accuracy value of the specific groove. In step S3, the step in which the measurement device obtains the design depth according to the jitter difference value and the depth reference information includes: After the measurement device determines that the sum of the jitter difference value and the bottom surface processing accuracy value is less than the crack disc threshold value, it takes the value that is greater than the sum of the jitter difference value and the bottom surface processing accuracy value and less than the crack disc threshold value as the design depth.

5. The pedestal processing method according to claim 1, wherein, The bearing surface of the base includes a central area and a bearing area surrounding the central area. The number of grooves is at least 2 and is arranged in the bearing area. In step S4, the step of forming a concave structure in the processing area of the base according to the design depth and the design opening size information includes: Form the concave structure in the area between adjacent grooves in the bearing area, or form the concave structure in the central area.

6. The base processing method according to claim 5, characterized in that, Adjacent grooves include a first groove and a second groove. The interval area between the first groove and the second groove is a first interval area, and the interval area close to the second groove and located in the bearing area is a second interval area. Step S4 further includes: Define the tangent line extending from the center of the middle region towards the first interval region and tangent to the first groove as the first tangent line, and the tangent line extending from the center of the middle region towards the second interval region and tangent to the second groove as the second tangent line. The enclosed area formed by the first tangent line, the second tangent line and the edge of the middle region is used as the machining area of the base.

7. The base processing method according to claim 5, characterized in that, The adjacent grooves include a first groove and a second groove. The interval region between the first groove and the second groove is the first interval region, and the interval region close to the second groove and located in the bearing region is the second interval region. In step S4, it further includes: Define the tangent line extending from the center of the middle region towards the first interval region and tangent to the first groove as the first tangent line, and the tangent line extending from the center of the middle region towards the first interval region and tangent to the second groove as the third tangent line. The sunken structure is arranged in the enclosed area formed by the first tangent line, the third tangent line and the edge of the middle region as the machining area of the base.

8. The base processing method according to claim 6 or 7, characterized in that, The edge of the middle region is tangent to the edge of each groove.

9. The base processing method according to claim 5, wherein, Each groove is evenly distributed around the central axis of the base. In step S4, the step of forming a sunken structure in the machining area of the base according to the design depth and the design opening size information includes: Form at least two sunken structures arranged in the same circumferential direction in the machining area.

10. The base processing method according to claim 1, characterized in that, The opening reference information includes the spot size of the ranging light beam emitted by the optical ranging device. In step S3, the step of obtaining the design opening size information according to the opening reference information includes: Take a value greater than the spot size as the design opening size information.

11. The base processing method according to claim 1, characterized in that, In step S4, the step of forming a sunken structure in the machining area of the base according to the design depth and the design opening size information includes: Remove part of the material of the base along the axial direction of the base from the top surface of the machining area to form the sunken structure, and make the opening size of the sunken structure larger than the bottom size.

12. The pedestal processing method according to any one of claims 1 to 11, characterized in that, The optical ranging device includes a blue light ranging device.

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