Semiconductor manufacturing equipment and control methods

Abstract

This invention provides a semiconductor manufacturing equipment and its control method. A lifting base plate is installed outside the chamber, surrounding a rotating device. Several lifting mechanisms are installed on the lifting base plate. A ranging device is used to obtain several external distances between the lifting base plate and the chamber floor plate. During the epitaxial process, each external distance is simultaneously acquired, and a determination is made based on these distances to determine whether base leveling is required. If so, the target lifting mechanism requiring lifting control is determined based on the external distances, along with corresponding lifting control parameters, including a target compensation displacement. The current rotational speed of the base is acquired, and the upper limit of the operating speed of the target lifting mechanism is obtained from a second calibration relationship based on the current rotational speed. The target lifting mechanism is then controlled to move the target compensation displacement corresponding to the obtained upper limit of the operating speed. This invention enables base leveling, avoiding impacts on production cycle time and efficiency, as well as the film deposition quality on the substrate.

Description

Technical Field

[0001] This invention relates to the field of semiconductor process equipment technology, and in particular to a semiconductor manufacturing equipment and its control method. Background Technology

[0002] Semiconductor manufacturing equipment, such as MOCVD (metal-organic chemical vapor deposition) equipment used for epitaxial growth of semiconductor material layers, frequently controls the base to rotate or lift due to process requirements or automated wafer transfer requirements.

[0003] Maintaining consistent spacing between the bearing surface of the substrate and the reference surface of the chamber below the gas injection device—that is, ensuring proper substrate levelness—plays a crucial role in controlling substrate transfer and film deposition performance. Slippage or component damage in the device controlling substrate lifting can easily cause deviations in substrate levelness. If this occurs during wafer transfer, the robotic arm used for transfer may deviate when picking up the substrate or coating substrate, potentially damaging the substrate or coating surface. If this occurs during the process, once the substrate levelness deviation exceeds a certain limit, it will significantly affect the stability of the substrate temperature field and the gas flow field near the substrate, thus negatively impacting film deposition performance.

[0004] Existing technologies typically involve leveling the substrate after shutdown. For example, opening the cavity after shutdown exposes the substrate and the cavity reference surface to the environment, and leveling is performed using optical ranging or other methods. This obviously has a significant impact on production cycle time and efficiency. Alternatively, in scenarios where a lifting device containing several lead screws is used to control the lifting of the substrate, the substrate is kept stationary, and the internal substrate is leveled by controlling the length of each lead screw on the external structure of the cavity. Although this method does not require opening the cavity, it will interrupt or even terminate the normally proceeding epitaxial growth process, which not only affects production cycle time and efficiency but also significantly impacts the film quality on the batch of substrates. Summary of the Invention

[0005] To address the problems of existing technologies affecting production cycle time and efficiency, as well as the film formation quality on the substrate during substrate leveling, this invention provides a semiconductor manufacturing equipment and its control method.

[0006] To achieve the above objectives, the present invention includes the following technical solutions:

[0007] In a first aspect, the present invention provides a control method for a semiconductor manufacturing equipment, the semiconductor manufacturing equipment including a chamber with an internal base, a rotating device that dynamically seals through the chamber and connects to the base, a lifting base plate disposed outside the rotating device, and a plurality of lifting mechanisms disposed on the lifting base plate and the chamber base plate of the chamber to drive the base to lift; there is an intracavity distance between the plane containing the top surface of the base and the chamber reference plane of the chamber;

[0008] The control method includes:

[0009] S0: Obtain the second calibration relationship between the jump threshold of the base at different rotation speeds and the upper limit of the operating speed of the lifting mechanism;

[0010] S1: Place the substrate on the base, control the rotating device to drive the base to rotate, and perform an epitaxial growth process on the substrate;

[0011] Step S1, during the epitaxial growth process, also includes performing:

[0012] S11: After obtaining and determining the need for base level adjustment based on the external distances between the lifting base plate and the chamber base plate, obtain the internal distances corresponding to the external distances, and determine the target lifting mechanism and corresponding lifting control parameters that need to be lifted based on the target internal distances.

[0013] S12: Obtain and match the upper limit of the operating rate in the second calibration relationship according to the current rotation speed of the base;

[0014] S13: Control the target lifting mechanism to move at the upper limit of the matching operating speed according to the lifting control parameters.

[0015] Furthermore, if the range of the external spacing of each cavity exceeds a preset range threshold, it is determined that the base level needs to be adjusted.

[0016] Further, step S0 also includes obtaining a first calibration relationship, the first calibration relationship being the correspondence between each of the external cavity spacings and the corresponding internal cavity spacings. In step S11, the step of obtaining each internal cavity spacing corresponding to each of the external cavity spacings includes: obtaining the corresponding internal cavity spacings according to each of the external cavity spacings and the first calibration relationship.

[0017] Further, before executing step S1, the step of obtaining the first calibration relationship is performed at room temperature, including:

[0018] S01: Control the process pressure within the chamber to maintain the requirements of the epitaxial growth process;

[0019] S02: Control each of the lifting mechanisms to run to a certain position, obtain the external cavity distance of each cavity and determine that the range of the obtained external cavity distances does not exceed a preset range threshold, then use an optical ranging device to obtain the internal cavity distance of each cavity and determine that the range of the internal cavity distances does not exceed a preset range threshold.

[0020] S03: The average value of several external cavity distances is used as the calibrated external cavity distance, and the average value of several internal cavity distances is used as the corresponding calibrated internal cavity distance.

[0021] S04: Control each of the aforementioned lifting mechanisms to rise or fall synchronously;

[0022] Repeat steps S02 to S04.

[0023] Furthermore, the range threshold does not exceed 0.05 mm.

[0024] Furthermore, the lifting control parameters include the target compensation distance and the target running direction. Step S11, determining the target lifting mechanism requiring lifting control and the corresponding lifting control parameters, includes:

[0025] The target lifting mechanism and the corresponding target compensation distance are determined based on the absolute value of the difference between the target cavity spacing and each of the cavity spacings.

[0026] The direction of movement of the target is determined based on the sign of the difference between the target cavity spacing and the difference between each cavity spacing.

[0027] Furthermore, the second calibration relationship includes:

[0028] The radial runout difference threshold of the base at different speeds not lower than the first speed threshold and the upper limit of the operating speed of the lifting mechanism are correlated, as are the axial runout difference threshold of the base at different speeds lower than the first speed threshold and the upper limit of the operating speed of the lifting mechanism.

[0029] Furthermore, it also includes obtaining axial runout difference thresholds and radial runout difference thresholds. In step S0, the step of obtaining the second calibration relationship is performed at room temperature, including:

[0030] P01: Control the process pressure within the chamber to maintain the requirements of the epitaxial growth process;

[0031] P02: Control the rotating device to drive the base to rotate at a fixed speed, control each of the lifting mechanisms to rise or fall synchronously at different speeds of motion, and use optical ranging to monitor the axial runout difference and radial runout difference of the base at each of the running speeds.

[0032] P03: Select the running rate corresponding to the runout difference value that reaches or is closest to the minimum value of the axial runout difference threshold and the radial runout difference threshold as the upper limit of the running rate under the fixed speed;

[0033] P04: Control the rotational device to increase the rotational speed of the base to another fixed speed;

[0034] Repeat steps P02 to P04.

[0035] Furthermore, the first speed threshold is not less than 400 rpm.

[0036] Further, after step P03 is completed, the external spacing of each cavity is obtained and its range is determined to be no more than a preset range threshold before step P04 is executed, or:

[0037] After step P03 is completed, each of the lifting mechanisms is controlled to run synchronously to the initial position of the base. Then, the external spacing of each cavity is obtained and its range is determined to be no more than the preset range threshold before step P04 is executed.

[0038] Furthermore, the second calibration relationship includes: the axial runout correspondence between the axial runout difference threshold of the base at different speeds below the first speed threshold and the upper limit of the operating speed of the lifting mechanism;

[0039] In step S12, after determining that the current rotation speed of the base is lower than the first rotation speed threshold, the upper limit of the operating speed of the lifting mechanism corresponding to the current rotation speed of the base is obtained according to the axial runout correspondence.

[0040] Furthermore, the second calibration relationship includes: the radial runout difference threshold of the base at different speeds not lower than the first speed threshold and the upper limit of the operating speed of the lifting mechanism;

[0041] In step S12, after determining that the current rotation speed of the base is not lower than the first rotation speed threshold, the upper limit of the operating speed of the lifting mechanism corresponding to the current rotation speed of the base is obtained according to the radial runout correspondence.

[0042] Furthermore, the second calibration relationship includes: the radial runout difference threshold of the base at different speeds not lower than the first speed threshold and the upper limit of the operating speed of the lifting mechanism;

[0043] In step S12, after determining that the current rotation speed of the base is higher than the second rotation speed threshold, the current rotation speed of the base is adjusted to a target rotation speed between the first rotation speed threshold and the second rotation speed threshold. The upper limit of the operating speed of the lifting mechanism corresponding to the target rotation speed of the base is obtained according to the radial runout correspondence. The second rotation speed threshold is higher than the first rotation speed threshold.

[0044] Furthermore, the first speed threshold is not less than 400 rpm, the second speed threshold is not less than 700 rpm, and the target speed is close to the second speed threshold compared to the first speed threshold.

[0045] Furthermore, the step of placing the substrate on the base includes controlling each of the lifting mechanisms to operate at a preset working speed, so that the base performs lifting movements to perform the transfer step of the substrate or coated substrate;

[0046] The operating rate is higher than the upper limit of each of the operating rates in the second calibration relationship.

[0047] In a second aspect, the present invention provides a semiconductor manufacturing apparatus, comprising:

[0048] A chamber and a base, wherein the base is disposed within the chamber;

[0049] A rotating device, with a dynamic seal penetrating the bottom of the chamber and rotatably connected to the base;

[0050] A lifting base plate is located outside the cavity and surrounds the rotating device;

[0051] Several lifting mechanisms are provided on the lifting base plate and connected to the chamber base plate of the chamber, so as to drive the base to move up and down through the rotating device;

[0052] A ranging device is used to obtain several external distances between the lifting base plate and the chamber base plate;

[0053] The main control device has a pre-stored second calibration relationship and is communicatively connected to the rotating device, each of the ranging devices, and each of the lifting mechanisms. The second calibration relationship is the correspondence between the jump threshold of the base at different rotation speeds and the upper limit of the operating speed of the lifting mechanism.

[0054] Furthermore, the bearing surface of the base faces the top of the chamber, the lifting mechanism includes a lead screw extending along the axial direction of the chamber, the top end of the lead screw is fixed to the bottom plate of the chamber, and the bottom end is fixed to the lifting base plate. The number of ranging devices is not less than the number of lead screws, and each ranging device is arranged in a corresponding manner near the connection between each lead screw and the bottom plate of the chamber, and / or in a corresponding manner near the connection between each lead screw and the lifting base plate.

[0055] By adopting the above technical solution, the semiconductor manufacturing equipment and its control method of the present invention have the following beneficial effects:

[0056] During the epitaxial growth process in step S1, which involves controlling the rotation of the substrate by a rotating device, after determining that the substrate needs to be leveled and obtaining the lifting mechanism and corresponding lifting control parameters that need to be lifted, there is no need to interrupt the epitaxial growth process or the rotation of the substrate it controls. Instead, while still controlling the rotation of the substrate by the rotating device, the movement rate of the corresponding lifting mechanism that needs to be lifted can be selected and controlled by judging the current rotation speed of the substrate. This achieves real-time leveling of the substrate inside the chamber, without interfering with the normal process and also contributing to good substrate film quality.

[0057] Specifically, the provided second calibration relationship is the correspondence between the base runout threshold at different rotational speeds and the upper limit of the operating speed of the lifting mechanism. The runout threshold is the maximum allowable base runout value for the epitaxial growth process at different rotational speeds. Based on the current rotational speed of the base, the corresponding upper limit of the operating speed of the lifting mechanism is obtained from this second calibration relationship. Using this upper limit to control the movement of the lifting mechanism, the desired lifting mechanism movement can be selected, allowing for the selection of the largest possible operating speed of the lifting mechanism without interfering with the normal process, thus completing the base leveling as quickly as possible while maintaining production efficiency. Attached Figure Description

[0058] Figure 1 This is a schematic diagram of the semiconductor manufacturing equipment of the present invention;

[0059] Figure 2 This is a schematic diagram of the process of leveling the base in step S1 of the control method of the present invention.

[0060] Figure 3 This is a graph showing the radial runout difference threshold and the axial runout difference threshold of the base at different rotational speeds in this invention.

[0061] Figure 4 This is a schematic diagram of the process for obtaining the second calibration relationship according to the present invention;

[0062] Figure 5 This is a schematic diagram illustrating the acquisition of the external cavity spacing and the internal cavity spacing in this invention;

[0063] Figure 6 This is a schematic diagram of the process for obtaining the first calibration relationship according to the present invention. Detailed Implementation

[0064] The following specific examples illustrate the implementation 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 embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.

[0065] It should be noted that the illustrations provided in this embodiment are only schematic representations of the basic concept of the present invention. Although the illustrations only show components related to the present invention and are not drawn according to the actual number, shape and size of the components, the shape, quantity, positional relationship and proportion of each component can be arbitrarily changed under the premise of realizing the technical solution of this invention, and the layout of the components may also be more complex.

[0066] As mentioned earlier, if the substrate levelness does not meet the requirements, it will affect the film quality. Existing technologies usually level the substrate after shutdown, such as opening the cavity after shutdown to expose the substrate and the reference surface of the cavity to the environment and leveling by means of optical ranging, which obviously will significantly affect the production cycle and efficiency. Alternatively, in the scenario of using a lifting device containing several lead screws to control the lifting of the substrate, after controlling the substrate to a stationary state, the internal substrate is leveled by controlling the length of each lead screw on the external structure of the cavity. Although this method does not require opening the cavity, it will interrupt or even terminate the epitaxial growth process that was originally proceeding normally, which not only affects the production cycle and efficiency, but also significantly affects the film quality on the batch of substrates.

[0067] In view of this, the present invention provides a semiconductor manufacturing apparatus and a control method thereof for real-time leveling of a substrate, especially a substrate in a rotating state, to avoid affecting production cycle and efficiency, as well as affecting the film formation quality on the substrate.

[0068] The semiconductor manufacturing equipment provided by this invention can be a chemical vapor deposition (CVD) device, and more specifically, a plasma-enhanced chemical vapor deposition (PECVD) device, a metal-organic chemical vapor deposition (MOCVD) device, etc. This invention provides semiconductor manufacturing equipment for implementing epitaxial growth processes. It should be understood that this equipment is merely exemplary.

[0069] like Figure 1 As shown, the semiconductor manufacturing equipment provided by the present invention includes a chamber 1 with a base 2 inside, a rotating device 3 that is dynamically sealed through the bottom of the chamber 1 and rotatably connected to the base 2, a lifting base plate 4 located outside the chamber 1 and surrounding the rotating device 3, and a plurality of lifting mechanisms 5 disposed on the lifting base plate 4 and connected to the chamber base plate 12 of the chamber 1. There are a plurality of external gaps between the lifting base plate and the chamber base plate, and there are internal gaps between the plane where the top surface of the base is located and the reference plane of the chamber that correspond one-to-one with each of the external gaps.

[0070] The control method provided by this invention includes:

[0071] S0: Obtain the second calibration relationship;

[0072] S1: Place the substrate on the pedestal and control the semiconductor manufacturing equipment to perform epitaxial growth on the substrate.

[0073] In step S0, the second calibration relationship is the correspondence between the runout threshold of the base at different speeds and the upper limit of the operating speed of the lifting mechanism. The runout threshold is the maximum runout value of the base allowed by the epitaxial growth process at different speeds.

[0074] During the epitaxial growth process in step S1, the rotating device is controlled to rotate the base.

[0075] Step S1, during the epitaxial growth process, also includes performing actions such as... Figure 2 The base leveling steps are shown below:

[0076] S11: Obtain the external spacing of each cavity and determine whether the base needs to be horizontally adjusted based on the external spacing of each cavity. If so, obtain the internal spacing of each cavity based on the target internal spacing and the external spacing of each cavity to determine the target lifting mechanism that needs to be lifted and the corresponding lifting control parameters.

[0077] S12: Obtain the current rotation speed of the base and, based on the current rotation speed of the base, obtain the upper limit of the operating speed of the target lifting mechanism in the second calibration relationship;

[0078] S13: Control the target lifting mechanism to move at the upper limit of the running speed obtained in step S12 according to the lifting control parameters.

[0079] The technical solution of this application will be described in detail below through specific embodiments.

[0080] Example 1

[0081] This embodiment provides a semiconductor manufacturing apparatus for performing epitaxial growth processes on a substrate. For example... Figure 1 The semiconductor manufacturing equipment shown (taking MOCVD equipment as an example) includes a chamber 1 with a base 2 inside. The chamber 1 includes a chamber reference surface 11. A rotating device 3 with a dynamic seal passing through the bottom of the chamber 1 and rotatably connected to the base 2 is also included. A lifting base plate 4 is located outside the chamber 1 and surrounds the rotating device 3. Several lifting mechanisms 5 are provided on the lifting base plate 4 and connected to the chamber base plate 12 of the chamber 1. Distance measuring devices 6 are provided one-to-one with each connection between each lifting mechanism 5 and the chamber base plate 12, and / or with each lifting mechanism 5 and the lifting base plate 4. The equipment also includes a main control device (not shown) that is communicatively connected to the rotating device 3, each distance measuring device 6 and each lifting mechanism 5.

[0082] In some embodiments, substrate 100 is a wafer.

[0083] In some embodiments, the number of lifting mechanisms 5 is at least 3.

[0084] In some embodiments, each lifting mechanism 5 is evenly arranged along the same circumference on the chamber floor 12 to ensure the smooth lifting and lowering operation of the rotating device 3.

[0085] In this embodiment, there are several external gaps between the lifting base plate 4 and the chamber base plate 12. The plane containing the top surface of the base 2 and the reference plane 11 of the chamber have an internal gap that corresponds one-to-one with each external gap.

[0086] In some embodiments, the chamber reference plane 11 and the chamber floor 12 are horizontally arranged.

[0087] The chamber 1 includes a top opening and a top cover 13, which closes the top opening during the manufacturing process. The chamber reference surface 11 is located at the top opening and is used as a leveling reference during the installation of the base after the chamber is opened.

[0088] The top surface of the base 2 faces the top of the chamber 1. The top surface is used to support the substrate 100 and to accommodate and limit it, so that the substrate 100 can rotate with the base 2.

[0089] In some embodiments, the base 2 is preferably made of graphite and has a disc-shaped structure. In some embodiments, the surface of the graphite base 2 is covered with a silicon carbide layer.

[0090] During epitaxial growth, a rotating device is controlled to rotate the base supporting the substrate to be coated, thereby improving film uniformity. For example... Figure 1 As shown, the base 2 is supported within the chamber 1 by the base support device 9, and the rotating device 3 is dynamically sealed through the bottom plate 12 of the chamber and connected to the base support device 9. The rotating device 3 is used to drive the base 2 to rotate, thereby causing the substrate 100 on the base 2 to rotate with the base 2. The specific implementation method is a conventional technique in this field and will not be described in detail here.

[0091] In some embodiments, the base support device 9 is located at the center of the bottom surface of the base 2, extends toward and connects to the rotating device 3, and drives the base 2 to rotate in a centrally driven manner. The specific implementation method is a conventional technique in the art.

[0092] The lifting mechanism 5 controls the raising or lowering of the base. The lifting mechanism 5 is located outside the chamber 1 and is fixedly connected to the rotating device 3. Specifically, the lifting mechanism 5 surrounds the rotating device 3. One end of the lifting mechanism 5 is fixed to the chamber floor plate 12, extends towards the lifting base plate 4, and is fixedly mounted on the lifting base plate 4. Since the rotating device 3 is dynamically sealed within the chamber 1, the lifting mechanism 5, by driving the lifting base plate 4, can simultaneously drive the synchronous movement of the rotating device 3, thereby causing the base 2 to rise or fall.

[0093] In some embodiments, reference is made to Figure 1 The lifting mechanism 5 includes a lead screw 51 and a drive mechanism 52. The drive mechanism 52 is located on the lead screw 51, which is fixedly mounted on the lifting base plate 4, extending towards and fixedly mounted on the chamber base plate 12. In some specific embodiments, the top end of the lead screw 51 is fixed to the chamber base plate 12 via a fixed seat (which allows the lead screw to rotate but restricts its axial movement). The lead screw 51 is fixed to the lifting base plate 4 via a nut and a flange or connecting block. The bottom end of the lead screw 51 is connected to the drive mechanism 52 (such as a servo motor or stepper motor) via a coupling. When the drive mechanism 52 is started, it drives the lead screw 51 to rotate. The nut of the lead screw 51, which cannot rotate, is driven by the rotating lead screw 51 to move linearly along the lead screw 51, thereby driving the lifting base plate 4 to move towards or away from the chamber base plate 12. This, in turn, drives the rotating device 3 to move synchronously towards or away from the upper cover 13, so that the base 2 can be lifted and lowered via the rotating device 3. The specific adaptation methods of the fixed seat on the chamber floor plate and the lead screw, as well as the specific adaptation methods of the lead screw with the nut and the flange or connecting block, are conventional technical means in this field and will not be elaborated here.

[0094] In some embodiments, the lead screw 51 extends axially along the chamber 1, and the reference surface 11 of the chamber and the bearing top surface of the base 2 are both perpendicular to the axial direction of the chamber 1.

[0095] exist Figure 1 In the example shown, the lifting base plate 4 is provided with three lifting mechanisms 5, each of which is driven by an independent drive mechanism 52. However, it should be understood that this embodiment is not limited to this. Each lifting mechanism 5 can also be driven independently by the same drive mechanism 52.

[0096] As described in the background art, the consistency of the spacing between the bearing top surface of the control base and the reference surface of the chamber below the gas injection device, i.e., the control of the base levelness, plays an important role in the control of the transfer substrate and the film formation performance.

[0097] Especially for epitaxial growth processes, it is well known in the art that epitaxial growth requires very high precision in substrate temperature control. Taking the fabrication of light-emitting diodes (LEDs) by growing GaN layers on silicon substrates using MOCVD equipment as an example, if the substrate temperature deviation is 1 degree Celsius, the center wavelength of the LED will deviate from the center wavelength required by the process design by more than 1 nm. In severe cases, it will fundamentally change the light emission performance of the fabricated LED. For example, the center wavelength of the LED will redshift, making it impossible to obtain the blue LED that was originally required.

[0098] In semiconductor manufacturing equipment, taking MOCVD equipment as an example, a heating device is installed below the substrate to heat the substrate in order to achieve precise temperature control. The substrate then transfers heat to the substrate to achieve temperature control. A certain distance exists between the heating device and the substrate to avoid interfering with the substrate's movement (e.g., lifting or rotating). Based on the process requirements for temperature and precision control, precise temperature control of the substrate is achieved by rationally designing the distance between the heating device and the substrate, the heating power, and combining this with the substrate's dimensional characteristics and related theories of heat conduction. This approach also contributes to the uniformity of the temperature field near the top surface of the substrate.

[0099] Furthermore, the gas flow field formed by the process gas provided by the gas injection device above the base support surface interacts with the temperature field near the base top surface. To facilitate process adjustments, a reasonable distance between the heating device and the base is usually designed while ensuring good levelness. If the levelness of the base changes beyond a certain limit and cannot be adjusted in time, it will obviously have an adverse effect on both the temperature and flow fields, causing changes in the substrate surface temperature.

[0100] In existing technologies, optical ranging methods are used during the manufacturing process. For example, a probe light is emitted from the spray channel of a gas injection device onto the base, and the distance between the base and the reference surface of the chamber is monitored in real time based on the reflected beam information. However, due to the high temperature of the epitaxial process, the high-temperature process gas in the chamber affects the probe light emitted from the optical ranging device and the reflected light. Even if the same optical ranging device measures the same position on the base, the data obtained under high temperature and normal temperature conditions will be different, resulting in a ranging error that cannot be ignored.

[0101] Therefore, this application relies on the ranging device 6 to obtain several external distances between the lifting base plate 4 and the chamber base plate 12, and uses the monitoring of the changes in the external distances to obtain the changes in the internal distances during the epitaxial growth process.

[0102] The measurement accuracy of the ranging device 6 can be adaptively selected according to the requirements for controlling the levelness of the base 2. For example, a measurement accuracy of 0.001 mm can be selected.

[0103] In this embodiment, as Figure 1 As shown, the ranging device 6 can be a through-beam sensor, with the transmitting and receiving ends of each ranging device 6 correspondingly arranged on the chamber floor 12 and the lifting base plate 4, respectively. In some specific embodiments, each ranging device 6 on the chamber floor 12 is arranged near the connection point between each lead screw 51 and the chamber floor 12, and each ranging device 6 on the lifting base plate 4 is arranged near the connection point between each lead screw 51 and the lifting base plate 4.

[0104] In some embodiments, the ranging device 6 may also be a reflective sensor, with each ranging device 6 being set one-to-one near the connection between each lead screw 51 and the chamber floor 12, or one-to-one near the connection between each lead screw 51 and the lifting floor 4.

[0105] In this embodiment, the ranging device 6 can be a laser sensor or an infrared sensor, without any specific restrictions, as long as it can accurately measure the distance between the lifting base plate 4 and the cavity base plate 12 outside the cavity.

[0106] exist Figure 1 In the example shown, the heating device 7 of this embodiment is supported by a heating support device 71. The heating support device 71 penetrates the chamber floor plate 12 and is disposed within the rotating device 3, but does not rotate with the rotating device 3. The specific implementation method is a conventional technique in the art.

[0107] In some embodiments, the rotating device 3 is centrally driven and mounted on the base 2, and the heating device 7 is supported by a heating support device 71 and arranged around a support device below the base 2, with the bottom of the heating support device disposed on the bottom surface of the cavity. The specific implementation method is a conventional technique in the art.

[0108] In this embodiment, an elastic sealing element 8 is also provided between the chamber floor plate 12 and the lifting floor plate 4. The elastic sealing element 8, together with the chamber floor plate 12 and the lifting floor plate 4, forms a sealed space, thereby achieving the sealing of the chamber 1. Specifically, the two ends of the elastic sealing element 8 are respectively sealed around the rotating device 3 on the chamber floor plate 12 and the lifting floor plate 4. The interior of the elastic sealing element 8 is hollow to allow the rotating device 3 to pass through.

[0109] In some embodiments, the resilient seal 8 is a bellows.

[0110] In this embodiment, the lifting, rotation, and leveling of the base 2 are all controlled by the main control device.

[0111] In some embodiments, the master control device pre-stores a second calibration relationship.

[0112] In some embodiments, the main control device pre-stores a first calibration relationship and a second calibration relationship.

[0113] Specifically, the first calibration relationship is the correspondence between the external spacing of each cavity and the internal spacing of each cavity.

[0114] In some embodiments, the master control device also monitors and controls the epitaxial growth process.

[0115] After the substrate 100 is placed on the base 2, the main control device controls the semiconductor manufacturing equipment to perform epitaxial growth on the substrate 100. During the epitaxial growth process, the rotating device 3 is controlled to drive the base 2 to rotate, and the following steps are performed simultaneously: obtaining the external spacing of each cavity and determining whether the base needs to be leveled based on the external spacing; if so, obtaining the corresponding internal spacing of each cavity based on the external spacing and the first calibration relationship to determine the target lifting mechanism that needs to be lifted and the corresponding lifting control parameters, including the target compensation displacement; obtaining the current rotation speed of the base 2 and obtaining the upper limit of the operating speed of the target lifting mechanism based on the current rotation speed of the base 2 in the second calibration relationship; finally, controlling the target lifting mechanism to move the target compensation displacement corresponding to the obtained upper limit of the operating speed.

[0116] Example 2

[0117] This embodiment provides a method for obtaining a second calibration relationship.

[0118] The second calibration relationship is the correspondence between the runout threshold of the base 2 at different speeds and the upper limit of the operating speed of the lifting mechanism 5. The runout threshold is the maximum runout value of the base allowed by the epitaxial growth process at different speeds.

[0119] In the rotation control of the base by the rotating device 3, the degree of base runout varies at different rotational speeds. Base runout is categorized into axial runout (i.e., the base moves up and down along its axial direction, such as vertically) and radial runout (i.e., the base swings left and right along its diametrical direction, such as horizontally). As long as the base has a certain speed, axial and radial runouts coexist, and their respective degrees of runout change differently with rotational speed, as detailed below. Figure 3 As shown, in Figure 3 In the graph, the horizontal axis represents the base rotational speed in rpm, and the vertical axis represents the runout difference in millimeters. It can be seen that radial runout tends to dominate at high speeds, while axial runout tends to dominate at low speeds.

[0120] The second calibration relationship in this embodiment includes: the radial runout difference threshold of the base 2 at different speeds not lower than the first speed threshold and the upper limit of the operating speed of the lifting mechanism; and the axial runout difference threshold of the base 2 at different speeds lower than the first speed threshold and the upper limit of the operating speed of the lifting mechanism.

[0121] During speed adjustment, adjusting the axial runout will reduce the corresponding radial runout. Taking all factors into consideration, the first speed threshold should be set no lower than 400 rpm.

[0122] This embodiment utilizes optical ranging to test the difference in runout between the radial and axial directions of the base. As mentioned earlier, optical ranging for measuring the distance in a high-temperature chamber has a significant measurement error. Therefore, this application performs calibration by rotating the base at room temperature.

[0123] This embodiment obtains the second calibration relationship at room temperature, such as Figure 4 As shown, the specific steps are as follows:

[0124] P01: The process pressure required to maintain the epitaxial growth process within control chamber 1;

[0125] P02: Control the rotating device 3 to drive the base 2 to rotate at a fixed speed, control each lifting mechanism 5 to rise or fall synchronously at different speeds of motion, and use optical ranging to monitor the axial runout difference and radial runout difference of the base at each running speed.

[0126] P03: Select the running speed corresponding to the running speed difference that reaches or is closest to the minimum value of the axial running speed difference threshold and the radial running speed difference threshold as the upper limit of the corresponding running speed under a fixed speed.

[0127] P04: Increase the rotation speed of the base 2 driven by the control rotation device 3 to another fixed speed;

[0128] Repeat steps P02 to P04 until the preset stop condition is met, and obtain the second calibration relationship.

[0129] During the process, the rotating device drives the base to rotate, which must overcome not only the base's own weight but also the influence of the pressure within the chamber on the base's rotation. The base's runout differs when rotating and adjusting the base simultaneously under atmospheric pressure compared to rotating and adjusting the base simultaneously under process pressure. Therefore, in step P01, the process pressure required for the epitaxial growth process is maintained in chamber 1. The subsequent calibration of the second calibration relationships (P02 to P04) is performed under this pressure atmosphere.

[0130] In step P02, specifically, the rotating device 3 drives the base 2 to rotate at a fixed speed. First, each lifting mechanism 5 is controlled to rise synchronously at a rate of V1 to the first position (e.g., rise by 1 mm). During this test, the axial runout difference and radial runout difference of the base are monitored. Then, each lifting mechanism 5 is controlled to rise synchronously at a rate of V2, which is higher than V1, to the second position (e.g., rise by another 1 mm). During this process, the axial runout difference and radial runout difference of the base are monitored again. The above process is repeated, with the rate increasing each time. More specifically, since the axial runout difference threshold and radial runout difference threshold are empirical values ​​obtained based on the requirements of the epitaxial growth process, this step continues until the monitored axial runout difference and radial runout difference of the base are both higher than the corresponding axial runout difference threshold and radial runout difference threshold.

[0131] After the step of calibrating the correspondence between the operating speed and the runout difference of different lifting mechanisms 5 at a fixed speed is completed, the speed at which the base is rotated by the control rotating device is increased to another fixed speed, and the above calibration process is repeated.

[0132] In some embodiments, after the steps (P02 and P03) of calibrating the correspondence between the operating speed and the runout difference of different lifting mechanisms 5 at a fixed speed are completed, the distance between each cavity is obtained by the ranging device. After determining that the range of each cavity distance value (i.e. the difference between the maximum and minimum values ​​in the data set) does not exceed the predetermined range threshold, it is proven that the levelness of the base meets the requirements. Then, the rotation speed of the rotating device driving the base to rotate is increased to another fixed speed (P04) to avoid the base levelness deviation caused by the previous calibration process from affecting the accuracy of subsequent calibrations.

[0133] In some embodiments, after the steps (P02 and P03) of calibrating the correspondence between the operating speed and runout difference of different lifting mechanisms 5 at a fixed rotational speed are completed, each lifting mechanism is controlled to synchronously run to the initial position of the base, the external distance of each cavity is obtained and its range is determined to be no more than a preset range threshold, and then step P04 is executed. This control method ensures that, for cases where the initial distance between the base and the cavity reference plane is small, the lifting position of the base will not be restricted and unable to obtain complete data for debugging (there may be no lifting space before the runout threshold is measured).

[0134] In some embodiments, it is preferable to control the base to rise for calibration in order to avoid the possibility of motion interference between the base and the heating device due to continuous descent.

[0135] In some embodiments, for epitaxial growth processes requiring very high temperature control accuracy, the distance between the heating device and the base is not large, typically 4-6 mm, to ensure the effectiveness and rapid controllability of heat transfer from the heating device to the base. In this case, to avoid the calibration of the base descent being limited by the distance between the base and the heating device and thus unable to obtain complete data, the base can be raised to its upper limit position first, and then the calibration of controlling the base descent can be performed.

[0136] During the calibration process described above, with the base 2 unloaded, an optical ranging device emits a ranging beam towards the rotating base 2 to acquire ranging information within the test time, and calculates the runout difference of the base based on the ranging information. Specifically, when it is necessary to acquire the axial runout difference, the ranging beam is incident on the top surface of the base 2 from above; when it is necessary to acquire the radial runout difference, the ranging beam is incident on the side wall of the base 2 radially.

[0137] More specifically, an optical ranging device emits probe light vertically onto the top surface of the base through an optical window on the gas injection device and a spray channel. The optical ranging device receives feedback light information, and the information from the probe light and feedback light is converted into corresponding voltage signals. After appropriate data processing, a jump bar graph of voltage change over time and the height values ​​of each base can be obtained. The specific data processing method and the implementation method of the optical ranging device are conventional techniques in this field. For example, the optical ranging device can be a laser rangefinder or a blue light rangefinder. Based on the change of each base height value within the test time, each jump difference value (the absolute value of the difference between the test height value and the initial height value, where the initial height value is the base height value measured at 0 rotation speed) can be obtained. The average value of each jump difference value is the jump difference value obtained under the corresponding axial jump condition at that rotation speed. Similarly, using an optical ranging device, probe light is emitted vertically onto the side wall of the base through an optical window on the side wall of chamber 1. Data processing based on the received feedback light information and the emitted probe light information can determine the radial distances of the base side wall from the light outlet. The runout difference at a given rotational speed can be obtained by observing the changes in radial distances over the test time. For example... Figure 3 As shown, with increasing rotational speed, the axial runout difference tends to decrease and the trend of change tends to be stable; while the radial runout difference tends to increase and the trend of change tends to increase. At high rotational speeds, radial runout is dominant (possibly due to high centrifugal force), while at low rotational speeds, axial runout is dominant (possibly due to the relatively high base gravity compared to centrifugal force).

[0138] It is well known to those skilled in the art that structural factors such as the backlash of the reducer in a rotary motor and the stability of the connection between the support shaft and the load-bearing device make radial and axial runout of the substrate unavoidable. For epitaxial growth processes, the rotation of the substrate also helps to drag the gas flow field, promoting homogenization and improving film quality. The rotation and runout of the substrate, combined with factors such as temperature and pressure, collectively affect the final film quality on the substrate. Epitaxial growth process design requires specific radial and axial runout thresholds. Generally, these thresholds are determined based on the specific epitaxial growth process and product performance requirements. For example, in a homogeneous silicon carbide epitaxial growth process on a 6-inch silicon carbide substrate, the product requires that the number of basal plane dislocations and stacking faults in the resulting silicon carbide epitaxial layer be below 20. In terms of process design, the process speed is 900 rpm, the process pressure is 100 mbar, and the flow rate of the process gas silane supplied by the gas injection device is controlled at 200 sccm~400 sccm, the flow rate of propane is 70 sccm~150 sccm, and the flow rate of hydrogen chloride is 2000 sccm~5000 sccm. The control requirements for axial runout are higher than those for radial runout. The runout difference of axial runout is controlled below 0.5 mm, and the runout difference of radial runout is controlled below 0.8 mm. For obtaining the second calibration relationship corresponding to this epitaxial growth process, in step P02, with the base rotating at 900 rpm and the pressure inside chamber 1 at 100 mbar, each lifting mechanism is controlled to move upward 1 mm at a rate of 0.1 mm / s. During this process, the runout difference corresponding to the axial runout and radial runout of the base is obtained and compared with the control difference required by the process. If it is determined that it does not exceed the process requirements, after confirming that the base is running smoothly, each lifting mechanism is controlled to move upward 1 mm at a rate of 0.2 mm / s. During this process, the runout of the base is continued to be obtained and determined to meet the process requirements. This process is repeated until the axial and radial runout differences obtained by controlling the lifting mechanism at a speed of 0.4 mm / s are close to the process requirements. However, the axial and radial runout differences obtained by controlling the lifting mechanism at a speed of 0.5 mm / s both exceed the process requirements. Therefore, 0.4 mm / s is taken as the upper limit of the operating speed of each lifting mechanism used for real-time leveling of the base at the current base speed (900 rpm).

[0139] Furthermore, during the monitoring of axial and radial runout differences, if the detected axial runout difference exceeds the corresponding runout difference threshold required by the process, while the radial runout difference does not exceed the corresponding runout difference threshold required by the process, the control speed of the lifting mechanism at which the detected axial runout difference exceeds the limit required by the process shall be taken as the test endpoint. The reverse is also true.

[0140] Furthermore, considering that this application requires real-time leveling of the substrate during the epitaxial growth process, i.e., when the substrate is rotating, the substrate's runout is significantly greater in this situation than when the substrate is only rotating. If the lifting rates of each lifting mechanism are not effectively controlled, the substrate's runout can easily interfere with the process gas flow field, thus affecting the film quality. For these reasons, to achieve real-time leveling of the substrate inside the chamber while controlling the rotation of the rotating device to drive the substrate's rotation, and without interfering with the normal process, this application needs to adjust the lifting mechanism's operating rate to an appropriate upper limit based on the correlation between the substrate's runout threshold at different rotation speeds and the upper limit of the lifting mechanism's operating rate.

[0141] The conventional technique in this field, which involves stopping the base rotation before controlling the lifting motion, obviously affects the stability of the gas flow field above the top surface of the base (a suitable base rotation speed creates drag mixing in the gas flow field above the base, which is beneficial to the uniformity of film formation). The reason for choosing an appropriate upper limit of the operating speed to move the lifting mechanism is to balance the impact of base bounce and lifting efficiency, so as to achieve rapid leveling of the base without interrupting the normal process, and to minimize or even avoid the adverse effects that leveling the base 2 might have on the growing semiconductor material layer during the process.

[0142] Example 3

[0143] This embodiment specifically provides the control process before performing the epitaxial growth process.

[0144] Step S1 includes: placing the substrate 100 on the base 2 and controlling the semiconductor manufacturing equipment to perform an epitaxial growth process on the substrate.

[0145] In step S1, the step of placing the substrate on the base includes: controlling each of the lifting mechanisms to operate at a preset working speed, so that the base can perform lifting and lowering movements to perform the transfer step of the substrate or coated substrate.

[0146] In this embodiment, chamber 1 is equipped with a gas injection device to supply process gas to the bearing top surface of the base, and an exhaust device to discharge exhaust gas from chamber 1 and maintain the pressure state within chamber 1. The specific implementation method is a conventional technique in the art.

[0147] The main control unit has pre-stored process program information, which includes steps for performing pre-transfer preparation, removing the substrate for coating, transferring the substrate to be coated onto the base 2, performing pre-epitaxy growth preparation, and performing the epitaxial growth process. Specifically, after one round of epitaxial growth, the main control unit controls the gas injection device to provide chemically inert purge gas into the chamber 1, controls the rotating device 3 to stop rotating so that the base 2 is stationary, and controls the heating device to stop working to cool down to the transfer temperature. After the pressure inside and outside the chamber 1 is equalized, the transfer port of the chamber 1 is opened, the base is raised to the transfer position opposite to the transfer port, the substrate for coating is transferred out of the base, the substrate to be coated is transferred from the transfer port onto the base, and then the base is lowered to the working position. After the main control device controls the wafer transfer port to the closed state, it controls the gas injection device and the exhaust device to make the pressure in chamber 1 reach the process pressure. After controlling the heating device to meet the process temperature requirements, it drives the base to rotate. Then, it controls the gas injection device to provide process gas for epitaxial growth into chamber 1 to carry out the epitaxial growth process.

[0148] In this application, the lifting mechanism 5 drives the rotating device 3 to move up and down, thereby raising or lowering the base. The lifting and lowering control of the base is performed between adjacent epitaxial growth processes. Since the base does not need to rotate, to accelerate the process cycle and improve production efficiency, the synchronous operating speed of each lifting mechanism driving the base does not need to consider the base's vibration; it operates at the maximum operating speed of the driving mechanism. That is, the operating speed is higher than the upper limit of each operating speed in the second calibration relationship.

[0149] Taking the specific silicon carbide epitaxial growth process described in Example 2 as an example, under a chamber pressure of 100 mbar, the lifting mechanism 5 controls the movement speed of the lifting motion at 3~5 mm / s.

[0150] Example 4

[0151] This embodiment provides a method for obtaining a first calibration relationship. The first calibration relationship is the correspondence between the external spacing of each cavity and the corresponding internal spacing of each cavity.

[0152] The meanings of the external spacing and the corresponding internal spacing of each cavity are as follows: Assuming there are three lifting mechanisms 5, taking the first lifting mechanism 5 as an example, this lifting mechanism 5 is vertically connected between the lifting base plate and the cavity floor plate (the lifting base plate and the cavity floor plate are horizontally parallel, and the lifting mechanism 5 is perpendicular to both plates), then as follows: Figure 5As shown, the distance between the two ends of the vertical connection is denoted as the first external cavity distance X01, and the distance between the two ends of the virtual structure extending along the cavity axis from the top surface of the base bearing to the cavity reference plane is denoted as the first internal cavity distance Y01. X01 corresponds to Y01. Similarly, the second external cavity distance X02 and its corresponding second internal cavity distance Y02, as well as the corresponding third external cavity distance X03 and its corresponding third internal cavity distance Y03, are obtained.

[0153] Similarly, to avoid the influence of hot gas inside the chamber on ranging accuracy during calibration, this embodiment obtains the first calibration relationship at room temperature, such as... Figure 6 As shown, the specific steps include:

[0154] S01: Control the process pressure within the chamber to maintain the requirements of the epitaxial growth process;

[0155] S02: Control each of the lifting mechanisms 5 to run to a certain position, obtain the external cavity distance of each cavity and determine that the range of the obtained external cavity distances does not exceed a preset range threshold, then use an optical ranging device to obtain the internal cavity distance of each cavity and determine that the range of the internal cavity distances does not exceed a preset range threshold.

[0156] S03: The average value of several external cavity distances is used as the calibrated external cavity distance, and the average value of several internal cavity distances is used as the corresponding calibrated internal cavity distance.

[0157] S04: Control each of the aforementioned lifting mechanisms to rise or fall synchronously.

[0158] Repeat steps S02 to S04 until all the external cavity spacings that need to be calibrated are completed, and the first calibration relationship is obtained.

[0159] The reason for controlling and maintaining the process pressure in chamber 1 in step S01 is explained in the discussion and analysis of step P01 in Example 2, and will not be repeated here.

[0160] In step S02, the range of several external distances between the lifting base plate 4 and the chamber base plate 12 is controlled to not exceed the preset range threshold. Theoretically, after the range of each external distance meets the requirements, the corresponding internal distances should also meet the requirements.

[0161] In step S02, after confirming that the range of several external cavity spacings meets the requirements, the range of each internal cavity spacing obtained by the optical ranging device is also judged. This is to further confirm that the relevant installation structures inside the cavity and the base support are stable and that there are no issues with the base's levelness due to their own structural reasons. If the external cavity spacing meets the range requirements, but the internal cavity spacing does not, the calibration process of the first calibration relationship should be stopped, and the internal support base structure should be investigated to determine if there are any problems causing the base to be unstable. If the range of internal cavity spacing is not further confirmed in step S02, the base with poor levelness will experience structural vibration under long-term process rotation control during subsequent processes, which will not only affect the quality of the process epitaxy but also more likely affect process safety.

[0162] In some embodiments, the range threshold does not exceed 0.05 mm.

[0163] In some more specific embodiments, the average value of several external cavity spacings (X01, X02, ..., X0m) is used as the calibration external cavity spacing, and the average value of several internal cavity spacings (Y01, Y02, ..., Y0m) is used as the corresponding calibration internal cavity spacing.

[0164] Example 5

[0165] This embodiment provides that during the epitaxial process in step S1, the following steps are also performed simultaneously:

[0166] S11: Obtain the external spacing of each cavity and determine whether the base needs to be leveled based on the external spacing of each cavity. If so, obtain the internal spacing of each cavity based on the external spacing of each cavity, and determine the target lifting mechanism that needs to be lifted and lowered based on the target internal spacing of each cavity and the internal spacing of each cavity, as well as the corresponding lifting and lowering control parameters. The lifting and lowering control parameters include the target compensation displacement.

[0167] S12: Obtain the current rotation speed of the base and, based on the current rotation speed of the base, obtain the upper limit of the operating speed of the target lifting mechanism in the second calibration relationship.

[0168] S13: Control the target lifting mechanism to move at the upper limit of the running speed obtained in step S12 according to the lifting control parameters.

[0169] Specifically, in step S11, the following steps are used to determine whether base level adjustment is required: determine whether the range of the distance between the outer sides of each cavity exceeds the preset range threshold. If so, base level adjustment is required; otherwise, base level adjustment is not required.

[0170] In some embodiments, the range threshold does not exceed 0.05 mm.

[0171] In step S11, the intracavity spacing is obtained according to the following steps: Based on the extracavity spacing and the first calibration relationship, the intracavity spacing corresponding to the extracavity spacing is obtained. Specifically, the extracavity spacing is matched with the extracavity spacing calibrated in the first calibration relationship, and the calibrated intracavity spacing corresponding to the matched extracavity spacing is taken as the intracavity spacing corresponding to the extracavity spacing.

[0172] In step S11, the lifting control parameters include the target compensation distance and the target running direction. In this embodiment, the target lifting mechanism and the corresponding lifting control parameters that need to be lifted are determined according to the following steps: First, the target lifting mechanism and its corresponding target compensation distance are determined according to the absolute value of the difference between the target cavity spacing and the spacing between each cavity; then, the corresponding target running direction is determined according to the positive or negative value of the difference between the target cavity spacing and the spacing between each cavity.

[0173] Specifically, firstly, the difference between the distance between each cavity and the distance between the target cavity is obtained. When the absolute value of the difference exceeds the allowable error range, the lifting mechanism corresponding to the distance between the corresponding cavities is taken as the target lifting mechanism that needs to be lifted and lowered, and the absolute value of the difference is taken as the target compensation distance corresponding to the target lifting mechanism. Then, the sign of the difference is determined. When the difference is positive, it means that the lifting position of the target lifting mechanism is too high, and its corresponding target running direction should be downward. Conversely, it means that the lifting position of the target lifting mechanism is too low, and its corresponding target running direction should be upward.

[0174] In some embodiments, the target cavity spacing is an average spacing value determined according to process requirements.

[0175] As mentioned earlier, radial runout of the base tends to dominate at high speeds, while axial runout tends to dominate at low speeds. Furthermore, the base speed in epitaxial growth processes is typically controlled at a relatively high level to facilitate the mixing of the gas flow field above the base. During process debugging, it was found that once the axial runout of the base is alleviated, the corresponding radial runout also improves. Therefore, at low speeds (i.e., below the first speed threshold), the upper limit of the operating speed for each lifting mechanism is selected based on the radial runout correlation; at high speeds (i.e., not below the second speed threshold), the upper limit of the operating speed for each lifting mechanism is selected based on the axial runout correlation.

[0176] Based on this, when step S12 determines that the current rotational speed of the base 2 is lower than the first rotational speed threshold, the upper limit of the operating speed of the lifting mechanism at the current rotational speed of the base 2 is obtained according to the aforementioned axial runout correspondence. When step S12 determines that the current rotational speed of the base is not lower than the first rotational speed threshold, the upper limit of the operating speed of the lifting mechanism at the current rotational speed of the base 2 is obtained according to the radial runout correspondence. Thus, the upper limit of the operating speed that best matches the runout effect at the current rotational speed of the base can be obtained.

[0177] Furthermore, as the base rotation speed increases, radial runout becomes more severe, and the degree of radial runout is greater than that of axial runout. This reduces the adjustable window for the lifting rate of the lifting mechanism 5, resulting in a very low rate. Therefore, to improve lifting efficiency and ensure safety, when the base 2's rotation speed is too high, it is preferable to first reduce its rotation speed before determining the upper limit of the operating rate. That is, after step S12 determines that the current rotation speed of the base 2 is not lower than the second rotation speed threshold, the current rotation speed of the base 2 is adjusted to a target rotation speed between the first and second rotation speed thresholds. Then, based on the radial runout correspondence, the upper limit of the operating rate of the lifting mechanism at the target rotation speed of the base is obtained, where the second rotation speed threshold is higher than the first rotation speed threshold.

[0178] Thus, the lifting mechanism was able to achieve the maximum possible lifting rate within the allowable range of base runout, balancing the impact of base runout and lifting efficiency. This enabled rapid leveling of the base without interrupting the normal process, and minimized or even avoided the adverse effects that leveling the base 2 might have on the growing semiconductor material layer during the process.

[0179] Preferably, the difference between the second speed threshold and the first speed threshold is no more than 400 rpm, the second speed threshold is not less than 700 rpm, and the target speed is close to the second speed threshold compared to the first speed threshold.

[0180] In this embodiment, during the epitaxial growth process in step S1, which involves controlling the rotation device 3 to drive the base 2 to rotate, after determining that the base needs to be leveled and obtaining the target lifting mechanism and corresponding lifting control parameters that need to be lifted, there is no need to interrupt the epitaxial growth process or the base rotation it controls. Instead, while still controlling the rotation device 3 to drive the base 2 to rotate, the movement rate of the target lifting mechanism that needs to be lifted is selected by judging the current rotation speed of the base 2. This achieves real-time leveling of the base 2 inside the chamber 1, without interfering with the normal process and also contributing to good substrate film quality.

[0181] Specifically, the provided second calibration relationship is the correspondence between the runout threshold of the base 2 at different rotational speeds and the upper limit of the operating speed of the lifting mechanism. The runout threshold is the maximum runout value of the base allowed by the epitaxial growth process at different rotational speeds. Based on the current rotational speed of the base 2, the upper limit of the operating speed of the corresponding lifting mechanism 5 is obtained from this second calibration relationship. The movement of the target lifting mechanism to be controlled is determined by using this upper limit of the operating speed. This allows for the selection of the largest possible operating speed of the lifting mechanism without interfering with the normal process, so as to complete the leveling of the base 2 as quickly as possible, while also taking into account production efficiency.

[0182] While specific embodiments of the present invention have been described above, those skilled in the art should understand that these are merely illustrative examples, and the scope of protection of the present invention is defined by the appended claims. Those skilled in the art can make various changes or modifications to these embodiments without departing from the principles and essence of the present invention, but all such changes and modifications fall within the scope of protection of the present invention.

Claims

1. A control method for semiconductor manufacturing equipment, characterized in that: The semiconductor manufacturing equipment includes a chamber with an internal base, a rotating device that passes through the chamber and connects to the base via a dynamic seal, a lifting base plate located outside the chamber and on the rotating device, and several lifting mechanisms located on the lifting base plate and the chamber base plate of the chamber to drive the base to rise and fall; there is an internal gap between the plane containing the top surface of the base and the chamber reference plane of the chamber, and the chamber reference plane is located at the top opening and is used as a leveling reference during the installation of the base after the chamber is opened; The control method includes: S0: Obtain the second calibration relationship between the jump threshold of the base at different rotation speeds and the upper limit of the operating speed of the lifting mechanism; S1: Place the substrate on the base, control the rotating device to drive the base to rotate, and perform an epitaxial growth process on the substrate; Step S1, during the epitaxial growth process, also includes performing: S11: After obtaining and determining the need for base level adjustment based on the external distances between the lifting base plate and the chamber base plate, obtain the internal distances corresponding to the external distances, and determine the target lifting mechanism and corresponding lifting control parameters that need to be lifted based on the target internal distances. S12: Obtain and match the upper limit of the operating rate in the second calibration relationship according to the current rotation speed of the base; S13: Control the target lifting mechanism to move at the upper limit of the matching operating speed according to the lifting control parameters.

2. The control method as described in claim 1, characterized in that, When the range of the external spacing of each cavity exceeds the preset range threshold, it is determined that the base level adjustment is required.

3. The control method as described in claim 1, characterized in that, Step S0 further includes obtaining a first calibration relationship, which is the correspondence between each external cavity spacing and the corresponding internal cavity spacing. Step S11 includes obtaining each internal cavity spacing corresponding to each external cavity spacing, which includes obtaining the corresponding internal cavity spacing according to each external cavity spacing and the first calibration relationship.

4. The control method as described in claim 3, characterized in that, The step of obtaining the first calibration relationship at room temperature includes: S01: Control the process pressure within the chamber to maintain the requirements of the epitaxial growth process; S02: Control each of the lifting mechanisms to run to a certain position, obtain the external cavity distance of each cavity and determine that the range of the obtained external cavity distances does not exceed a preset range threshold, then use an optical ranging device to obtain the internal cavity distance of each cavity and determine that the range of the internal cavity distances does not exceed a preset range threshold. S03: The average value of several external cavity distances is used as the calibrated external cavity distance, and the average value of several internal cavity distances is used as the corresponding calibrated internal cavity distance. S04: Control each of the aforementioned lifting mechanisms to rise or fall synchronously; Repeat steps S02 to S04.

5. The control method according to any one of claims 2 or 4, characterized in that, The range threshold does not exceed 0.05 mm.

6. The control method as described in claim 1, characterized in that, The lifting control parameters include the target compensation distance and the target running direction. Step S11, which involves determining the target lifting mechanism requiring lifting control and the corresponding lifting control parameters, includes: The target lifting mechanism and the corresponding target compensation distance are determined based on the absolute value of the difference between the target cavity spacing and each of the cavity spacings. The direction of movement of the target is determined based on the sign of the difference between the target cavity spacing and the difference between each cavity spacing.

7. The control method as described in claim 1, characterized in that, The second calibration relationship includes: The radial runout difference threshold of the base at different speeds not lower than the first speed threshold and the upper limit of the operating speed of the lifting mechanism are related by radial runout. The relationship between the axial runout difference threshold of the base at different speeds below the first speed threshold and the upper limit of the operating speed of the lifting mechanism.

8. The control method as described in claim 7, characterized in that, It also includes obtaining axial runout difference thresholds and radial runout difference thresholds. In step S0, the step of obtaining the second calibration relationship is performed at room temperature, including: P01: Control the process pressure within the chamber to maintain the requirements of the epitaxial growth process; P02: Control the rotating device to drive the base to rotate at a fixed speed, control each of the lifting mechanisms to rise or fall synchronously at different speeds of motion, and use optical ranging to monitor the axial runout difference and radial runout difference of the base at each of the running speeds. P03: Select the running rate corresponding to the runout difference value that reaches or is closest to the minimum value of the axial runout difference threshold and the radial runout difference threshold as the upper limit of the running rate under the fixed speed; P04: Control the rotational device to increase the rotational speed of the base to another fixed speed; Repeat steps P02 to P04.

9. The control method as described in claim 7, characterized in that, The first speed threshold is not less than 400 rpm.

10. The control method as described in claim 7, characterized in that: After step P03 is completed, obtain the external spacing of each cavity and determine that its range does not exceed the preset range threshold, then execute step P04, or: After step P03 is completed, each of the lifting mechanisms is controlled to run synchronously to the initial position of the base. Then, the external spacing of each cavity is obtained and its range is determined to be no more than the preset range threshold before step P04 is executed.

11. The control method as described in claim 1, characterized in that: The second calibration relationship includes: the axial runout difference threshold of the base at different speeds below the first speed threshold and the upper limit of the operating speed of the lifting mechanism; In step S12, after determining that the current rotation speed of the base is lower than the first rotation speed threshold, the upper limit of the operating speed of the lifting mechanism corresponding to the current rotation speed of the base is obtained according to the axial runout correspondence.

12. The control method as described in claim 1, characterized in that: The second calibration relationship includes: the radial runout difference threshold of the base at different speeds not lower than the first speed threshold and the upper limit of the operating speed of the lifting mechanism; In step S12, after determining that the current rotation speed of the base is not lower than the first rotation speed threshold, the upper limit of the operating speed of the lifting mechanism corresponding to the current rotation speed of the base is obtained according to the radial runout correspondence.

13. The control method as described in claim 1, characterized in that: The second calibration relationship includes: the radial runout difference threshold of the base at different speeds not lower than the first speed threshold and the upper limit of the operating speed of the lifting mechanism; In step S12, after determining that the current rotation speed of the base is higher than the second rotation speed threshold, the current rotation speed of the base is adjusted to a target rotation speed between the first rotation speed threshold and the second rotation speed threshold. The upper limit of the operating speed of the lifting mechanism corresponding to the target rotation speed of the base is obtained according to the radial runout correspondence. The second rotation speed threshold is higher than the first rotation speed threshold.

14. The control method as described in claim 13, characterized in that, The first speed threshold is not less than 400 rpm, the second speed threshold is not less than 700 rpm, and the target speed is close to the second speed threshold compared to the first speed threshold.

15. The control method as described in claim 1, characterized in that, In step S1, the step of placing the substrate on the base includes: controlling each of the lifting mechanisms to operate at a preset working speed, so that the base can perform lifting and lowering movements to perform the transfer step of the substrate or coated substrate; The operating rate is higher than the upper limit of each of the operating rates in the second calibration relationship.

16. A semiconductor manufacturing apparatus, characterized in that, include: A chamber and a base, wherein the base is disposed within the chamber; A rotating device, with a dynamic seal penetrating the bottom of the chamber and rotatably connected to the base; A lifting base plate is located outside the cavity and surrounds the rotating device; Several lifting mechanisms are provided on the lifting base plate and connected to the chamber base plate of the chamber, so as to drive the base to move up and down through the rotating device; A ranging device is used to obtain several external distances between the lifting base plate and the chamber base plate; The main control device has a pre-stored second calibration relationship and is communicatively connected to the rotating device, each of the ranging devices, and each of the lifting mechanisms. The second calibration relationship is the correspondence between the jump threshold of the base at different rotation speeds and the upper limit of the operating speed of the lifting mechanism.

17. The semiconductor manufacturing apparatus as claimed in claim 16, characterized in that, The bearing surface of the base faces the top of the chamber. The lifting mechanism includes a lead screw extending along the axial direction of the chamber. The top end of the lead screw is fixed to the bottom plate of the chamber, and the bottom end is fixed to the lifting base plate. The number of ranging devices is not less than the number of lead screws. Each ranging device is arranged in a corresponding manner near the connection between each lead screw and the bottom plate of the chamber, and / or near the connection between each lead screw and the lifting base plate.

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