Method for dynamically controlling growth rate of center / edge regions in semiconductor epitaxy process

Abstract

This application discloses a method for dynamically controlling the growth rate of the center / edge region in a semiconductor epitaxial process. The method includes: during the growth of a target epitaxial layer, acquiring the ratio of infrared radiation sensors at the center and edge, and determining the dynamic rotation speed of a substrate based on a preset first mapping relationship; the first mapping relationship is defined as the correspondence between the ratio of the infrared radiation sensors at the center and edge and the dynamic rotation speed of the substrate; determining the growth rate of the center / edge region of the target epitaxial layer according to the dynamic rotation speed of the substrate and a preset second mapping relationship; the second mapping relationship is defined as the correspondence between the growth rate of the center / edge region and the dynamic rotation speed of the substrate; acquiring the target growth rate of the center / edge region of the target epitaxial layer, and dynamically adjusting the dynamic rotation speed of the substrate to ensure that the growth rate of the center / edge region of the target epitaxial layer conforms to the target growth rate. This application can dynamically control the growth rate of the center / edge region of the target epitaxial layer.

Description

Technical Field

[0001] This application relates to the field of semiconductor device manufacturing, and specifically to a method for dynamically controlling the growth rate of the center / edge region in a semiconductor epitaxial process. Background Technology

[0002] A superjunction (SJ) is a structure based on the traditional vertical double-diffused metal-oxide-semiconductor (VDMOS). By introducing a superjunction structure, it forms an alternating arrangement of P-pillars and N-epitaxies (N-EPI) in the vertical direction, replacing the N-drift region of the traditional VDMOS structure. Superjunctions not only offer advantages such as small size, light weight, fast switching speed, high integration, and high voltage withstand capability, but also overcome the limitation of DMOS (double-diffused metal-oxide-semiconductor) where high breakdown voltage and low on-resistance cannot coexist. They are now widely used in power supplies, adapters, charging stations, and other market sectors.

[0003] Currently, the main manufacturing processes for superjunction MOSFETs (Metal-Oxide-Semiconductor Field-Effect Transistors) are atmospheric voltage epitaxy and vacuum epitaxy, which are applied to two types of products: multilayer epitaxial superjunctions (i.e., multi-EPI SJ, planar epitaxial growth) and deep trench superjunctions (deep trench SJ, deep trench selective epitaxial filling). For example... Figure 1 As shown, a deep trench superjunction typically includes: a substrate 1; an N-type epitaxial layer 2 located on the substrate 1; a deep trench formed in the N-type epitaxial layer 2; and an oxide isolation layer 3 disposed on the top of the sidewall of the deep trench; the target epitaxial layer 4 needs to be grown in the deep trench to form a P-type pillar.

[0004] The target epitaxial layer for deep trench superjunction growth typically falls into one of the following two categories: (1) For some simple DTI (Deep Trench Isolation) devices, such as Figure 2 As shown, structures with a low AR (Aspect Ratio, i.e., the ratio of trench depth to width) (AR≤10) and identical AR at the center and edges can achieve uniform epitaxial filling of the inner and outer rings by adjusting the power distribution ratio or airflow distribution ratio of the inner and outer rings.

[0005] However, using the power distribution ratio between the inner and outer rings to control the epitaxial growth rate is not only prone to thermal stress slip line defects due to uneven local thermal stress, but also causes fluctuations in the doping concentration of the inner and outer rings with power changes, affecting the consistency of the device's electrical performance. Furthermore, this method relies on the percentage distribution of power between the inner and outer rings, making it impossible to achieve independent and precise adjustment of the growth rate in the center and edge regions. When using the airflow distribution ratio between the inner and outer rings to control the epitaxial growth rate, the reaction airflow always contacts and reacts with the wafer edge region first, leading to an excessively fast epitaxial growth rate at the edges, resulting in a severe micro-loading effect and edge overfilling. Secondly, the airflow between the inner and outer rings can only be distributed according to a preset percentage, making it impossible to achieve independent and precise adjustment of the growth rate in the center and edge regions.

[0006] (2) For some complex DTI devices, such as those with high AR (AR>10, e.g.) Figure 3 As shown), the center and edge AR are different (e.g. Figure 4 As shown), the extremely high integration results in a small pitch (e.g. Figure 5 (as shown), or novel trench structures (such as...) Figure 6 In cases such as those shown, the key is to avoid creating voids in the deep trenches during the epitaxial process. Otherwise, it will cause problems such as insufficient reverse breakdown voltage and reverse leakage, affecting product yield.

[0007] Taking the different structures of the center and edge AR as an example, existing inner and outer ring power percentage or airflow percentage control is adopted: (1) If the inner and outer circles are at a constant speed or the inner circle is faster than the outer circle: This will cause a large number of voids to be generated at the Center position, such as Figure 7 As shown; (2) If the inner slow speed and outer fast speed method is adopted: ① As the percentage changes, a void may appear at the bottom, middle, or top of the Center position, such as... Figure 8 As shown; ② The outer ring has a high speed, resulting in a significant loading effect and thicker edge overfiling, which affects CMP (chemical mechanical polishing) grinding. Figure 8 As shown; (3) If the inner circle is used at a very slow speed: ① As the percentage changes, the edge growth rate may become too fast, resulting in voids, such as... Figure 9 As shown; ② The outer ring has a high speed, resulting in a significant loading effect and thicker edge overfiling, which affects CMP grinding. Figure 9 As shown.

[0008] Therefore, existing control methods based on the distribution of power or airflow between the inner and outer rings cannot achieve independent dynamic control of the growth rate of the central and peripheral regions. Summary of the Invention

[0009] The main objective of this application is to provide a method for dynamically controlling the growth rate of the center / edge region in a semiconductor epitaxial process, thereby achieving real-time monitoring and dynamic control of the growth rate of the center / edge region during semiconductor epitaxial growth.

[0010] The technical solution adopted in this application is: In a first aspect, this application provides a method for dynamically controlling the growth rate of the center / edge region in a semiconductor epitaxial process, comprising: During the growth of the target epitaxial layer, the ratio of the central and edge infrared radiation sensors is obtained, and the dynamic rotation speed of the base is determined based on a preset first mapping relationship; wherein, the first mapping relationship is defined as the correspondence between the ratio of the central and edge infrared radiation sensors and the dynamic rotation speed of the epitaxial machine base. Based on the determined dynamic rotation speed of the base and the preset second mapping relationship, the growth rate of the target epitaxial layer center / edge region is determined; wherein, the second mapping relationship is defined as the correspondence between the growth rate of the target epitaxial layer center / edge region and the dynamic rotation speed of the base; The target growth rate of the center / edge region of the target epitaxial layer is obtained. Based on the determined growth rate of the center / edge region of the target epitaxial layer and the second mapping relationship, the dynamic rotation speed of the base is dynamically adjusted so that the growth rate of the center / edge region of the target epitaxial layer conforms to the target growth rate.

[0011] According to the above technical solution, the dynamic rotational speed of the base is R=K×S, where S is the initial rotational speed of the base and K is the introduced dynamic coefficient used to control the rotational speed and direction of rotation of the base. When K<0, the base rotates in the opposite direction.

[0012] Following the above technical solution, the rotation speed and direction of the base are dynamically controlled by the dynamic coefficient K, so as to dynamically introduce the gas from the transverse airflow port of the epitaxial machine into the center or edge region of the target epitaxial layer, forming a competitive reaction with the silicon source gas introduced by the main air inlet, thereby dynamically controlling the growth rate of the center / edge region of the target epitaxial layer.

[0013] Following the above technical solution, the main air inlet is supplied with the first carrier gas, silicon source gas, and dopant gas, while the transverse airflow port is supplied with the second carrier gas and hydrogen chloride gas.

[0014] According to the above technical solution, the first carrier gas and the second carrier gas are hydrogen, the silicon source gas is dichlorosilane or trichlorosilane, and the doping gas is diborane.

[0015] Following the above technical solution, when the rotation direction of the base is opposite to the gas direction of the transverse airflow port, the gas in the transverse airflow port is introduced into the central region of the target epitaxial layer. By controlling the rotation speed of the base, the growth rate of the central region of the target epitaxial layer is dynamically controlled. When the rotation direction of the base is the same as the gas direction of the transverse airflow port, the gas in the transverse airflow port is introduced into the edge region of the target epitaxial layer. The growth rate of the target epitaxial layer edge region is dynamically controlled by controlling the rotation speed of the base.

[0016] Following the above technical solution, the target epitaxial layer is an N-type single-crystal silicon epitaxial film or a P-type single-crystal silicon epitaxial film.

[0017] Following the above technical solution, the actual rotation speed of the epitaxial machine base is periodically obtained. If the ratio of the infrared radiation sensor values ​​at the center and edge of the target epitaxial layer does not conform to the preset first mapping relationship with the actual rotation speed of the base, the epitaxial machine is abnormal.

[0018] Secondly, this application provides a system for dynamically controlling the growth rate of the center / edge region of a semiconductor epitaxial process, comprising: The first mapping module is used to acquire the ratio of the central and edge infrared radiation sensors during the growth of the target epitaxial layer, and determine the dynamic rotation speed of the base based on a preset first mapping relationship; wherein, the first mapping relationship is defined as the correspondence between the ratio of the central and edge infrared radiation sensors and the dynamic rotation speed of the epitaxial machine base. The second mapping module is used to determine the growth rate of the target epitaxial layer center / edge region based on the determined dynamic rotation speed of the base and the preset second mapping relationship; wherein, the second mapping relationship is defined as the correspondence between the growth rate of the target epitaxial layer center / edge region and the dynamic rotation speed of the base; The dynamic control module is used to obtain the target growth rate of the center / edge region of the target epitaxial layer, and dynamically control the dynamic rotation speed of the base in combination with the determined growth rate of the center / edge region of the target epitaxial layer and the second mapping relationship, so that the growth rate of the center / edge region of the target epitaxial layer conforms to the target growth rate.

[0019] Thirdly, this application provides an epitaxial machine including a controller, the controller being configured to perform a method for dynamically controlling the growth rate of the center / edge region of a semiconductor epitaxial process as described in any of the first aspects.

[0020] The beneficial effects of this application are as follows: The first mapping relationship is defined as the correspondence between the ratio of the infrared radiation sensors at the center and edge of the target epitaxial layer and the dynamic rotation speed of the substrate. The second mapping relationship is defined as the correspondence between the growth rate of the center / edge region of the target epitaxial layer and the dynamic rotation speed of the substrate. An unexpected effect is that in the first mapping relationship, the ratio of the infrared radiation sensors at the center and edge is linear with the dynamic rotation speed, while in the second mapping relationship, only the growth rate of one region is linear with the dynamic rotation speed, and the growth rate of the other region is relatively stable. Therefore, the ratio of the infrared radiation sensors at the center and edge of the target epitaxial layer can be obtained in real time during the epitaxial growth process of the target epitaxial layer. Based on the preset first mapping relationship, the dynamic rotation speed of the substrate can be determined, and then the growth rate of the center / edge region of the target epitaxial layer can be determined according to the second mapping relationship. This achieves real-time monitoring of the growth rate of the center / edge region of the target epitaxial layer during the epitaxial process. Furthermore, based on the real-time growth rate feedback, the dynamic rotation speed of the substrate can be dynamically adjusted, achieving real-time dynamic control of the growth rate of a specific region (center / edge) during the epitaxial growth process of the target epitaxial layer.

[0021] Furthermore, this application introduces a dynamic coefficient K, which is a dynamic variable controlling the rotational speed and direction of the base. This dynamically controls the clockwise or counterclockwise rotation direction and speed of the base, thereby dynamically introducing hydrogen chloride gas from the transverse airflow port of the epitaxial machine to the center or edge region of the target epitaxial layer. This gas competes with the silicon source gas introduced through the main air inlet, thus dynamically controlling the growth rate of the center / edge region of the target epitaxial layer. Specifically, by setting the sign and magnitude of the dynamic coefficient K, the location and amount of hydrogen chloride gas introduced are controlled, thereby selectively suppressing the silicon source reaction rate in that region and achieving independent dynamic control of the growth rate of the center / edge region.

[0022] Furthermore, when the rotation direction of the base is the same as the direction of the hydrogen chloride gas, the hydrogen chloride gas enters the edge region, and the growth rate of the edge region is linear with the dynamic rotation speed, while the growth rate of the central region is not linear with the dynamic rotation speed, thus realizing dynamic control of the growth rate of the edge region; conversely, when the rotation direction of the base is opposite to the direction of the hydrogen chloride gas, the hydrogen chloride gas enters the central region, and the growth rate of the central region is linear with the dynamic rotation speed, while the growth rate of the edge region is not linear with the dynamic rotation speed, thus realizing dynamic control of the growth rate of the central region.

[0023] Of course, any product implementing this application does not necessarily need to achieve all of the advantages described above at the same time. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a schematic diagram of the structure of a Deep trench SJ in the prior art; Figure 2 This is a schematic diagram of a simple DTI device in the prior art; Figure 3 A schematic diagram of a DTI device with high AR in the prior art; Figure 4 A schematic diagram of a DTI device with different center and edge AR in the prior art; Figure 5 This is a schematic diagram of a highly integrated DTI device in the current technology; Figure 6 This is a schematic diagram of a novel trench structure DTI device in the prior art; Figure 7 This is a schematic diagram illustrating the defects that occur when the inner and outer rings move at a constant speed or the inner ring moves faster than the outer ring in the existing technology. Figure 8 This is a schematic diagram illustrating the defects that occur when the existing technology uses a slow inner speed and fast outer speed method. Figure 9 This is a schematic diagram illustrating the defects that arise when the inner ring is used in the existing technology with an extremely slow inner ring. Figure 10A This is a flowchart illustrating a method for dynamically controlling the growth rate of the center / edge region in a semiconductor epitaxial process according to an embodiment of this application. Figure 10B This is a block diagram illustrating a method for dynamically controlling the growth rate of the center / edge region in a semiconductor epitaxial process according to an embodiment of this application. Figure 10C This is a flowchart illustrating a method for dynamically controlling the growth rate of the center / edge region of a semiconductor epitaxial process according to another embodiment of this application. Figure 11 This is a schematic diagram of a wafer rotating counterclockwise according to an embodiment of this application; Figure 12 This is a schematic diagram of a wafer rotating clockwise according to an embodiment of this application; Figure 13 This is a layout diagram of an infrared radiation sensor according to an embodiment of this application; Figure 14 This is a schematic diagram of the first mapping relationship according to an embodiment of this application; Figure 15 This is a schematic diagram of the second mapping relationship according to an embodiment of this application; Figure 16 This is a comparison diagram showing the effects of prior art and the method of this application in an embodiment of this application; Figure 17 This is a schematic diagram showing the X-flow direction reversed according to an embodiment of this application.

[0026] In the figure: 1. Substrate; 2. N-type epitaxial layer; 3. Oxide isolation layer; 4. Target epitaxial layer; 5. Central region infrared radiation sensor; 6. Edge region infrared radiation sensor; 7. Main air inlet; 8. Lateral airflow port; 9. Exhaust port; 10. Wafer. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0028] It should be noted that the illustrations provided in the embodiments of this application are only schematic representations of the basic concept of this application. Therefore, the illustrations only show the components related to this application and are not drawn according to the number, shape and size of the components in actual implementation. In actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0029] In this application, it should also be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application. Furthermore, the terms "first" and "second" are used only for descriptive and distinguishing purposes and should not be construed as indicating or implying relative importance.

[0030] Furthermore, it should be noted that the features of the various embodiments of this application can be combined or integrated in whole or in part, and as those skilled in the art will understand, they can interact and operate in different ways. Each embodiment can be implemented independently of each other, or implemented in a related relationship.

[0031] This application provides a method for dynamically controlling the growth rate of the center / edge region in a semiconductor epitaxial process. By introducing a dynamic coefficient K, this method can monitor the growth rate of the center / edge region in real time according to the mapping relationship during the epitaxial growth of the target epitaxial layer and achieve dynamic control, effectively providing a novel method for dynamically controlling the growth rate of the epitaxial center / edge region.

[0032] Example 1 like Figure 10A and Figure 10B As shown in the embodiments of this application, a method for dynamically controlling the growth rate of the center / edge region of a semiconductor epitaxial process is provided, including: S101. When growing the target epitaxial layer, the ratio of the central and edge infrared radiation sensors is obtained, and the dynamic rotation speed of the base is determined based on a preset first mapping relationship; wherein, the first mapping relationship is defined as the correspondence between the ratio of the central and edge infrared radiation sensors and the dynamic rotation speed of the epitaxial machine base. S102. Based on the determined dynamic rotation speed of the base and the preset second mapping relationship, determine the growth rate of the target epitaxial layer center / edge region; wherein, the second mapping relationship is defined as the correspondence between the growth rate of the target epitaxial layer center / edge region and the dynamic rotation speed of the base; S103. Obtain the target growth rate of the center / edge region of the target epitaxial layer, and dynamically adjust the dynamic rotation speed of the base in combination with the determined growth rate of the center / edge region of the target epitaxial layer and the second mapping relationship, so that the growth rate of the center / edge region of the target epitaxial layer conforms to the target growth rate.

[0033] This application acquires the ratio of infrared radiation sensors at the center and edge of the target epitaxial layer in real time during the epitaxial growth process of the target epitaxial layer. Based on a preset first mapping relationship, it determines the dynamic rotation speed of the substrate, and then determines the growth rate of the center / edge region of the target epitaxial layer according to a preset second mapping relationship, thereby realizing real-time monitoring of the growth rate of the center / edge region of the target epitaxial layer in the epitaxial process. Furthermore, it acquires the target growth rate of the center / edge region of the target epitaxial layer, and combines the determined growth rate of the center / edge region of the target epitaxial layer with the second mapping relationship to dynamically adjust the dynamic rotation speed of the substrate, so that the growth rate of the center / edge region of the target epitaxial layer conforms to the target growth rate, thereby realizing real-time dynamic control of the growth rate of a specific region (center / edge) during the epitaxial growth process of the target epitaxial layer.

[0034] Specifically, when the rotation direction of the base is opposite to the gas direction of the transverse airflow port, the gas in the transverse airflow port is introduced into the central region of the target epitaxial layer. The growth rate of the central region of the target epitaxial layer is dynamically controlled by controlling the rotation speed of the base. When the rotation direction of the base is the same as the gas direction of the transverse airflow port, the gas in the transverse airflow port is introduced into the edge region of the target epitaxial layer. The growth rate of the target epitaxial layer edge region is dynamically controlled by controlling the rotation speed of the base.

[0035] Example 2 like Figure 10C As shown in the embodiments of this application, the method for dynamically controlling the growth rate of the center / edge region of a semiconductor epitaxial process mainly includes the following steps: Step S201: Provide multiple wafer substrates and place the wafer substrates in the epitaxial machine cavity to grow the target epitaxial layer.

[0036] In this embodiment, the wafer substrate is a superjunction product substrate, and the superjunction product includes at least a multi-EPI superjunction (Multi-EPI SJ) and a deep trench superjunction (Deep trench SJ). The epitaxial equipment includes at least atmospheric pressure and reduced pressure epitaxial equipment. The target epitaxial layer includes at least an N-type single-crystal silicon epitaxial film and a P-type single-crystal silicon epitaxial film.

[0037] This embodiment uses a reduced-pressure epitaxy machine as an example. Figure 11 and Figure 12 As shown, during the growth of the target epitaxial layer, hydrogen is used as the carrier gas at the main inlet 7 (Inject position) to introduce the silicon source and doping gas; hydrogen is used as the carrier gas at the lateral flow port 8 (X-flow position) to introduce HCl gas. These gases are used to grow the target epitaxial layer on wafer 10, and the reacted gases are discharged from the exhaust port 9. The silicon source is either dichlorosilane (DCS) or trichlorosilane (TCS).

[0038] Specifically, the flow rate of the silicon source is 300~3000 sccm; the doping gas is B2H6, the mix ratio is 0~100%, and the inlet flow rate is 0~500 sccm; the carrier gas introduced at the Inject position is H2, with a flow rate of 0~100 slm; the carrier gas introduced at the X-flow position is also H2, with a flow rate of 0~2000 sccm; and the flow rate of HCl gas introduced at the X-flow position is 0~1000 sccm.

[0039] Step S202: Introduce a dynamic coefficient K during the growth process of the target epitaxial layer to dynamically control the dynamic rotation speed R of the substrate, so that the substrate drives the wafer substrate to rotate at different dynamic rotation speeds R; where R = K × S, S is the initial rotation speed of the substrate, and R is the dynamic rotation speed after correction by the dynamic coefficient K.

[0040] In this embodiment, the dynamic coefficient K is a dynamic variable that controls the rotational speed and direction of the base. When K < 0, the base will rotate in the opposite direction. The initial rotational speed of the base is the speed at which the base rotates clockwise or counterclockwise, and its value ranges from 0 to 48 rpm.

[0041] For example, if the initial rotation direction of the initial rotational speed S of the base is counterclockwise, then: When K > 0, the base maintains its initial counterclockwise rotation, and the rotational speed increases as the value of K increases; When K < 0, the base rotates in the opposite direction (i.e., clockwise), and the absolute value of its rotational speed increases as the value of |K| increases.

[0042] Step S203: During the growth of multiple target epitaxial layers, different values ​​of the dynamic coefficient K are set to obtain different dynamic rotation speeds R. Based on the relationship between the ratio of the center / edge infrared radiation sensor at the machine end and the different dynamic rotation speeds R, a first mapping relationship is established.

[0043] In this embodiment, by setting multiple different values ​​for the dynamic coefficient K, multiple different dynamic rotation speeds R are obtained, thereby growing the target epitaxial layer at different dynamic rotation speeds R. Infrared radiation sensors 5 in the center region and 6 in the edge region, respectively set at the center and edge of the machine tool, are used to acquire infrared radiation readings from the center and edge regions, respectively. The ratio of the center / edge infrared radiation sensors at the machine tool is used as an example. Figure 13 As shown in the figure. The ratio of the center / edge infrared radiation sensors at the machine end is the ratio of the reading of the infrared radiation sensor 5 in the central region of the cavity to the reading of the infrared radiation sensor 6 in the edge region.

[0044] In this embodiment, the initial rotation direction of the base's initial rotational speed S is counterclockwise. For example... Figure 14 As shown, the first mapping relationship is obtained by fitting the ratio of the infrared radiation sensors in the center / edge regions to the dynamic rotational speed R=K×S: (1) When K < 0, R < 0, and the linearity after fitting reaches 0.989; (2) When K > 0, R > 0, and the linearity after fitting reaches 0.997.

[0045] It is evident that the ratio of infrared radiation sensors in the center / edge region exhibits a good linear relationship with the dynamic rotational speed R, providing a reliable basis for real-time monitoring and feedback control of subsequent epitaxial processes.

[0046] Step S204: Perform FTIR measurements on the multiple target epitaxial layers obtained in step S203, and establish a second mapping relationship between the measured growth rates of the center / edge regions of different target epitaxial layers and different dynamic rotation speeds R.

[0047] In this embodiment, FTIR (Fourier Transform Infrared Spectroscopy) measurement of multiple target epitaxial layers involves using an FTIR optical measurement device to accurately measure the multiple target epitaxial layers obtained in step S203, in order to obtain the growth rate of the center / edge regions of the target epitaxial layers. For example... Figure 15 As shown, the second mapping relationship is obtained by fitting the dynamic rotational speed R with the normalized growth rate of the center / edge region: (1) When K < 0, R < 0, and the linearity of the growth rate of the edge region reaches 0.9333 after fitting, but there is no linearity with the growth rate of the center region. (2) When K>0, R>0, and the linearity of the growth rate in the central region reaches 0.9988 after fitting, while the linearity of the growth rate in the edge region is not linear.

[0048] Therefore, when it is necessary to control the growth rate of the edge region, K < 0 is set, and the rotation speed is controlled by the value of K, thereby controlling the growth rate of the edge region; when it is necessary to control the growth rate of the center region, K > 0 is set, and the rotation speed is controlled by the value of K, thereby controlling the growth rate of the center region.

[0049] This is because the HCl gas introduced through the transverse airflow port 8 can undergo the following reversible competitive reaction with the silicon source introduced through the main air inlet 7, thereby achieving dynamic control of the growth rate in a specific region: (1) When TCS is used as the silicon source: SiHCl3 + H2 Si + 3HCl; (2) When DCS is used as the silicon source: SiH2Cl2 Si + 2HCl.

[0050] Specifically, when K > 0, the base rotates counterclockwise, and the wafer rotates counterclockwise as follows: Figure 11 As shown, the HCl gas rotates in the opposite direction to the Wafer, and the HCl gas enters the central region of the Wafer, thereby controlling the growth rate in the central region. When K < 0, the base rotates clockwise, and the wafer rotates clockwise as follows: Figure 12 As shown, the HCl gas rotates in the same direction as the Wafer, and the HCl gas enters the edge region of the Wafer, thereby controlling the growth rate of the edge region.

[0051] Specifically, when the initial rotation direction of the base's initial rotational speed S is counterclockwise, that is, opposite to the direction in which hydrogen chloride gas is introduced through the transverse airflow port, in the first mapping relationship: When K > 0, R > 0, the ratio of the center and edge infrared radiation sensors is linear with the dynamic rotational speed; When K < 0, R < 0, the ratio of the center and edge infrared radiation sensors is linear with the dynamic rotation speed; In the second mapping relationship: When K > 0, R > 0, the direction of hydrogen chloride gas is opposite to the direction of wafer substrate rotation, and hydrogen chloride gas enters the central region of wafer substrate. The growth rate of the central region is linear with the dynamic rotation speed, while the growth rate of the edge region is not linear with the dynamic rotation speed, thus realizing dynamic control of the growth rate of the central region. When K < 0, R < 0, the direction of hydrogen chloride gas is the same as the rotation direction of the wafer substrate, and the hydrogen chloride gas enters the edge region of the wafer substrate. The growth rate of the edge region is linear with the dynamic rotation speed, while the growth rate of the center region is not linear with the dynamic rotation speed, thus realizing dynamic control of the growth rate of the edge region.

[0052] When the initial rotation direction of the base's initial rotational speed S is clockwise, that is, the same as the direction in which hydrogen chloride gas is introduced into the transverse airflow port, in the first mapping relationship: When K > 0, R > 0, the ratio of the center and edge infrared radiation sensors is linear with the dynamic rotational speed; When K < 0, R < 0, the ratio of the center and edge infrared radiation sensors is linear with the dynamic rotation speed; In the second mapping relationship: When K > 0, R > 0, the direction of hydrogen chloride gas is the same as the rotation direction of the wafer substrate, and the hydrogen chloride gas enters the edge region of the wafer substrate. The growth rate of the edge region is linear with the dynamic rotation speed, while the growth rate of the center region is not linear with the dynamic rotation speed, thus realizing dynamic control of the growth rate of the edge region. When K < 0, R < 0, the direction of hydrogen chloride gas is opposite to the rotation direction of the wafer substrate, and the hydrogen chloride gas enters the central region of the wafer substrate. The growth rate of the central region is linear with the dynamic rotation speed, while the growth rate of the edge region is not linear with the dynamic rotation speed, thus realizing dynamic control of the growth rate of the central region.

[0053] The initial rotation direction of the base (clockwise or counterclockwise) determines the initial setting of the above "opposite" and "same" relationship, but does not change the core control logic.

[0054] Step S205: In the subsequent epitaxial process, the dynamic rotation speed R value is obtained by comparing the ratio of the infrared radiation sensor at the center / edge of the machine end with the pre-established first mapping relationship.

[0055] In this embodiment, in the subsequent epitaxial process, the ratio of the infrared radiation sensor at the center / edge of the machine end can be obtained. This ratio is the actual output value in the subsequent epitaxial growth process. Then, combined with the pre-established first mapping relationship, the corresponding dynamic rotation speed R value can be obtained.

[0056] Step S206: Compare the dynamic rotation speed R value obtained in step S205 with the pre-established second mapping relationship to obtain the real-time growth rate of the center / edge region during the epitaxial growth process.

[0057] In this embodiment, the real-time growth rate of the center / edge region during the epitaxial growth process is obtained by mapping the actual output ratio of the center / edge infrared radiation sensor in step S205 through the first mapping relationship and the second mapping relationship.

[0058] Step S207: Based on the real-time growth rate of the center / edge region during epitaxial growth obtained in step S206, the value of K is dynamically controlled by the controller to achieve real-time dynamic control of the growth rate of the center / edge region during epitaxial growth.

[0059] Specifically, the real-time dynamic control process is as follows: it is determined whether the real-time growth rate obtained in step S206 has reached the preset process target (i.e., the target growth rate). If it is not met, the value of the dynamic coefficient K is adjusted by the controller according to the second mapping relationship, thereby changing the dynamic rotation speed of the base, and finally regulating the growth rate to the target range, thus dynamically controlling the real-time growth rate of the center / edge region during the epitaxial growth process.

[0060] Therefore, this application introduces a dynamic coefficient K, which is a dynamic variable controlling the rotational speed and direction of the substrate. This dynamically controls the clockwise or counterclockwise rotation direction and speed of the substrate, thereby dynamically introducing hydrogen chloride gas from the transverse airflow port of the epitaxial machine to the center or edge region of the target epitaxial layer. This gas competes with the silicon source gas introduced through the main air inlet, thus dynamically controlling the growth rate of the center / edge region of the target epitaxial layer. Specifically, by setting the sign and magnitude of the dynamic coefficient K, the location and amount of hydrogen chloride gas introduced are controlled, thereby selectively suppressing the silicon source reaction rate in that region and achieving independent dynamic control of the growth rate of the center / edge region.

[0061] like Figure 16 As shown, for complex DTI devices, using existing inner / outer ring power distribution ratios or inner / outer ring airflow distribution ratios can lead to voids and overfilling at the edges. However, the method of dynamically controlling the growth rate of the center / edge regions in semiconductor epitaxial processes described in this application—that is, dynamically controlling the real-time growth rate of the center / edge regions during epitaxial growth—can effectively avoid these problems. Specifically, for... Figure 16 For the various poor filling conditions in the prior art on the left, a good epitaxial filling result can be obtained by adopting the growth rate control method of this application corresponding to the right.

[0062] It should be noted that this application achieves real-time monitoring of the growth rate through a first mapping relationship and a second mapping relationship, and achieves dynamic control of the growth rate by dynamically adjusting the K value through a controller. Although the readings of the center / edge infrared radiation sensor and the dynamic rotation speed R can be obtained by the system in real time, the introduction of the first mapping relationship is of great importance for the following reasons: Firstly, while the center / edge region and dynamic rotation speed R can indeed be directly obtained from real-time run-time values ​​using methods such as FDC (Fault Detection & Classification, a monitoring tool that can detect machine and product parameters in real time), a key technical aspect of this application is utilizing the HCl gas flowing out from the X-flow point to enter the center or edge of the wafer under dynamic rotation speed, thereby controlling the growth rate at the corresponding location. Under normal circumstances, monitoring and dynamic control can be achieved using a second mapping relationship between the dynamic rotation speed R and the growth rate of the center and edge regions. However, if the machine undergoes preventative maintenance (PM) and the equipment engineer reverses the X-flow direction, or if the X-flow HCl MFC (mass flow controller) experiences linear drift (a situation that has occurred in practice), such as… Figure 17 As shown, at this point, relying solely on the second mapping relationship, using the dynamic rotation speed R uploaded by FDC and the second mapping relationship to monitor and dynamically control the center / edge growth rate, is insufficient to provide feedback on the true rate and achieve the expected control results.

[0063] Secondly, the center / edge infrared radiation sensor obtains data by receiving the reflected wavelength after infrared light shines on the wafer surface. At different epitaxial growth rates, the wavelength received by the sensor varies, enabling monitoring of the growth rate in the center / edge regions of the cavity. Therefore, after introducing the first mapping relationship, under normal circumstances, the linearity of the first mapping relationship will not change. If the aforementioned equipment malfunction occurs, the first mapping relationship will directly show a linear change, thereby accurately identifying the problem and stopping it, preventing wafer trouble.

[0064] Therefore, this application can obtain the ratio of the center and edge infrared radiation sensors and the dynamic rotation speed of the base in real time during subsequent epitaxial processes; if the ratio of the center and edge infrared radiation sensors and the dynamic rotation speed of the base do not satisfy the linear relationship of the first mapping relationship, the epitaxial machine is abnormal, and timely reminders can be given to avoid economic losses.

[0065] Therefore, this application utilizes the first and second mapping relationships to achieve real-time monitoring of the growth rate, and uses a controller to dynamically control the parameters of K to achieve dynamic control during epitaxial growth. Specifically, this application introduces a dynamic coefficient K to dynamically control the clockwise or counterclockwise direction and rotation speed of the base, dynamically introducing the HCl gas entering from the X-flow into the center or edge position of the wafer. The gas dynamically entering the center or edge position of the wafer competes with the introduced silicon source, thereby achieving dynamic control of the growth rate of the center / edge region during the epitaxial growth process.

[0066] Compared with existing technologies, this method provides a novel dynamic control mechanism for the growth rate of the epitaxial center / edge region: existing technologies mainly rely on the inner and outer ring power distribution ratio (regulating heat) or the inner and outer ring airflow distribution ratio (regulating mass transfer) to adjust the growth rate. This application, however, introduces a dynamic coefficient K to directly and dynamically control the rotation direction and speed of the base, thereby actively regulating the lateral airflow port (X). The distribution of injected HCl gas in the center and edge regions of the wafer surface (flow). By combining dual mapping relationship and feedback control, real-time monitoring and dynamic control of the growth rate in the center / edge regions during epitaxial growth were achieved for the first time.

[0067] Furthermore, this method enables individual control of the growth rate in the center and edge regions: In existing technologies, both power distribution and airflow distribution employ fixed percentage adjustments, resulting in an increase in the inner growth rate inevitably leading to a decrease in the outer growth rate, and vice versa. These two factors mutually constrain each other, making independent control of a single region impossible. This application, through precise control of the rotation direction and speed using a dynamic coefficient K, can independently accelerate or suppress the central region while maintaining a relatively constant growth rate in the edge region, or vice versa. This significantly improves the flexibility and precision of process control, making it particularly suitable for manufacturing devices with varying aspect ratios and complex structures.

[0068] It should be noted that the method for dynamically controlling the growth rate of the center / edge region of a semiconductor epitaxial process in this application is applicable not only to the dynamic control of the growth rate of the center / edge region of the target epitaxial layer of a superjunction product, but also to the dynamic control of the growth rate of the center / edge region of the target epitaxial layer of a semiconductor.

[0069] Example 3 To illustrate the implementation process and effects of this method, a typical technological process will be used as an example below: Step S301: Provide multiple Wafer substrates and place the Wafer substrates in the epitaxial machine cavity to grow the target epitaxial layer.

[0070] Specifically, the wafer substrate is a superjunction product substrate; the epitaxial machine cavity is a reduced-pressure epitaxial machine, model AMAT EPI Prime; the target epitaxial layer is a P-type single-crystal silicon epitaxial thin film with a thickness of 3.5 μm.

[0071] Step S302: Introduce a dynamic coefficient K during the growth process of the target epitaxial layer, which is briefly described as R=K×S, where S is the initial rotation speed of the base and R is the dynamic rotation speed after the dynamic coefficient K is corrected.

[0072] Specifically, the dynamic coefficient K takes values ​​of -1, -0.83, -0.67, -0.5, -0.33, -0.17, 0.17, 0.33, 0.5, 0.67, 0.83, and 1. The initial rotational speed of the base is 48 rpm, and the initial rotation direction is counterclockwise. Therefore: When K < 0, the base rotates clockwise to control the growth rate of the edge region. The values ​​of R = K × S are as follows: R1 = -48 (K = -1), R2 = -40 (K = -0.83), R3 = -32 (K = -0.67), R4 = -24 (K = -0.5), R5 = -16 (K = -0.33), R6 = -8 (K = -0.17). When K > 0, the base rotates counterclockwise to control the growth rate of the central region. The values ​​of R = K × S are as follows: R7 = 8 (K = 0.17), R8 = 16 (K = 0.33), R9 = 24 (K = 0.5), R10 = 32 (K = 0.67), R11 = 40 (K = 0.83), R12 = 48 (K = 1).

[0073] Step S303: During the growth of multiple target epitaxial layers, different values ​​of K are set to obtain different rotation speeds R. Based on the ratio of the infrared radiation sensor at the center / edge of the machine end and the relationship between different rotation speeds R, a first mapping relationship is established.

[0074] Specifically, the silicon source at the injection position is DCS with a flow rate of 900 sccm; the doping gas at the injection position is B2H6 with a mix ratio of 60% and an inlet flow rate of 350 sccm; the carrier gas at the injection position is H2 with a flow rate of 45 slm; the carrier gas at the X-flow position is H2 with a flow rate of 1250 sccm; and the HCl gas at the X-flow position has a flow rate of 250 sccm. The first mapping relationship is established based on the K value set in step S2 for epitaxial growth, and a mapping relationship is established based on the ratio of the center / edge infrared radiation sensor at the machine end and different rotational speeds R.

[0075] Step S304: Perform FTIR measurements on the multiple target epitaxial layers obtained in step S303, and establish a second mapping relationship between the measured growth rates of the center / edge regions of different target epitaxial layers and different rotation speeds R.

[0076] Specifically, FTIR measurement involves measuring multiple wafers obtained in step S303 to obtain the growth rates of multiple center / edge regions. The second mapping relationship establishes a mapping relationship between the growth rates of different target epitaxial layer center / edge regions obtained from FTIR measurement and different rotational speeds R.

[0077] Step S305: In the subsequent epitaxial process, the dynamic R value is obtained by comparing the ratio of the infrared radiation sensor at the center / edge of the machine end with the pre-established first mapping relationship.

[0078] Specifically, when K < 0, the ratio of the infrared radiation sensor at the center / edge of the machine end is 2.646. Compared with the pre-established first mapping relationship, the dynamic R value is -40.

[0079] Step S306: Compare the dynamic R value obtained in step S305 with the pre-established second mapping relationship to obtain the real-time growth rate of the center / edge region during the epitaxial growth process.

[0080] Specifically, according to step S305, the dynamic R value is -40. Comparing it with the second mapping relationship, the real-time growth rate of the edge region is 0.181 μm / min.

[0081] Step S307: Based on the real-time growth rate of the center / edge region during epitaxial growth obtained in step S306, the value of K is dynamically controlled by the controller according to the second mapping relationship to realize the real-time dynamic control of the growth rate of the center / edge region during epitaxial growth.

[0082] Specifically, it is determined whether the real-time growth rate obtained in step S306 meets the actual process requirements (target growth rate 0.173 μm / min). Since 0.181 μm / min is greater than 0.173 μm / min, combined with the second mapping relationship, it can be seen that the rotation speed needs to be reduced. Therefore, the value of K can be dynamically changed to -0.67 by the controller to achieve dynamic control.

[0083] The superjunction device prepared by the method of this application has high epitaxial filling structure uniformity, good consistency of deep trench filling quality in the center and edge regions, effectively avoids void defects and edge overfilling problems, and has excellent electrical performance and reliability.

[0084] It should be noted that this embodiment only sets the values ​​-1, -0.83, -0.67, -0.5, -0.33, -0.17, 0.17, 0.33, 0.5, 0.67, 0.83, and 1. Those skilled in the art should know that other values ​​are also allowed, including values ​​greater than 1. Furthermore, when implementing real-time dynamic control of the growth rate, the corresponding target K value can also be directly calculated based on the mapping relationship.

[0085] Example 4 This application provides a system for dynamically controlling the growth rate of the center / edge region in a semiconductor epitaxial process, used to implement the above-described method embodiments. The system includes: The first mapping module is used to acquire the ratio of the central and edge infrared radiation sensors during the growth of the target epitaxial layer, and determine the dynamic rotation speed of the base based on a preset first mapping relationship; wherein, the first mapping relationship is defined as the correspondence between the ratio of the central and edge infrared radiation sensors and the dynamic rotation speed of the epitaxial machine base. The second mapping module is used to determine the growth rate of the target epitaxial layer center / edge region based on the determined dynamic rotation speed of the base and the preset second mapping relationship; wherein, the second mapping relationship is defined as the correspondence between the growth rate of the target epitaxial layer center / edge region and the dynamic rotation speed of the base; The dynamic control module is used to obtain the target growth rate of the center / edge region of the target epitaxial layer, and dynamically control the dynamic rotation speed of the base in combination with the determined growth rate of the center / edge region of the target epitaxial layer and the second mapping relationship, so that the growth rate of the center / edge region of the target epitaxial layer conforms to the target growth rate.

[0086] Example 5 This application also provides an epitaxial machine tool for implementing the above-mentioned dynamic control method, including: A rotatable base for supporting wafer substrates is located inside the cavity of the epitaxial machine. The main air inlet and the lateral airflow port are used to introduce process gases; Infrared radiation sensors are respectively installed in the regions corresponding to the center and edge of the wafer within the epitaxial machine cavity, for real-time monitoring of infrared radiation signals during the growth process; FTIR optical metrology equipment is used to measure the completed epitaxial layer to obtain the precise growth rate of the center / edge region; The controller is connected to an infrared radiation sensor, an FTIR optical measurement device, and a rotatable base drive mechanism. The controller is configured to perform a method for dynamically controlling the growth rate of the center / edge region of a semiconductor epitaxial process according to the above method embodiment, that is, dynamically calculating and adjusting the rotation speed and direction of the base according to the sensor signal and a preset mapping relationship, thereby realizing real-time dynamic control of epitaxial growth.

[0087] In summary, the method for dynamically controlling the growth rate of the center / edge region in a semiconductor epitaxial process provided in this application defines a first mapping relationship as the correspondence between the ratio of the infrared radiation sensors at the center and edge of the target epitaxial layer and the dynamic rotation speed of the substrate, and a second mapping relationship as the correspondence between the growth rate of the center / edge region of the target epitaxial layer and the dynamic rotation speed of the substrate. An unexpected effect is that in the first mapping relationship, the ratio of the infrared radiation sensors at the center and edge is linear with the dynamic rotation speed, while in the second mapping relationship, only the growth rate of one region is linear with the dynamic rotation speed, and the growth rate of the other region is relatively stable. Therefore, the ratio of the infrared radiation sensors at the center and edge of the target epitaxial layer can be obtained in real time during the epitaxial growth process of the target epitaxial layer. Based on the preset first mapping relationship, the dynamic rotation speed of the substrate can be determined, and then the growth rate of the center / edge region of the target epitaxial layer can be determined according to the second mapping relationship. This achieves real-time monitoring of the growth rate of the center / edge region of the target epitaxial layer in the epitaxial process, and further, based on the real-time growth rate feedback, the dynamic rotation speed of the substrate can be dynamically adjusted to achieve real-time dynamic control of the growth rate of a specific region (center / edge) during the epitaxial growth process of the target epitaxial layer.

[0088] Furthermore, this application introduces a dynamic coefficient K, which is a dynamic variable controlling the rotational speed and direction of the base. This dynamically controls the clockwise or counterclockwise rotation direction and speed of the base, thereby dynamically introducing hydrogen chloride gas from the transverse airflow port of the epitaxial machine to the center or edge region of the target epitaxial layer. This gas competes with the silicon source gas introduced through the main air inlet, thus dynamically controlling the growth rate of the center / edge region of the target epitaxial layer. Specifically, by setting the sign and magnitude of the dynamic coefficient K, the location and amount of hydrogen chloride gas introduced are controlled, thereby selectively suppressing the silicon source reaction rate in that region and achieving independent dynamic control of the growth rate of the center / edge region.

[0089] Furthermore, when the rotation direction of the base is the same as the direction of the hydrogen chloride gas, the hydrogen chloride gas enters the edge region, and the growth rate of the edge region is linear with the dynamic rotation speed, while the growth rate of the central region is not linear with the dynamic rotation speed, thus realizing dynamic control of the growth rate of the edge region; conversely, when the rotation direction of the base is opposite to the direction of the hydrogen chloride gas, the hydrogen chloride gas enters the central region, and the growth rate of the central region is linear with the dynamic rotation speed, while the growth rate of the edge region is not linear with the dynamic rotation speed, thus realizing dynamic control of the growth rate of the central region.

[0090] It should be noted that, depending on the implementation needs, the various steps / components described in this application can be broken down into more steps / components, or two or more steps / components or parts of the operation of a step / component can be combined into a new step / component to achieve the purpose of this application.

[0091] The order of the steps in the above embodiments does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0092] It should be understood that those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the scope of protection of the appended claims.

Claims

1. A method for dynamically controlling the growth rate of the center / edge region in a semiconductor epitaxial process, characterized in that, include: During the growth of the target epitaxial layer, the ratio of the central and edge infrared radiation sensors is obtained, and the dynamic rotation speed of the base is determined based on a preset first mapping relationship; wherein, the first mapping relationship is defined as the correspondence between the ratio of the central and edge infrared radiation sensors and the dynamic rotation speed of the epitaxial machine base. Based on the determined dynamic rotation speed of the base and the preset second mapping relationship, the growth rate of the target epitaxial layer center / edge region is determined; wherein, the second mapping relationship is defined as the correspondence between the growth rate of the target epitaxial layer center / edge region and the dynamic rotation speed of the base; The target growth rate of the center / edge region of the target epitaxial layer is obtained. Based on the determined growth rate of the center / edge region of the target epitaxial layer and the second mapping relationship, the dynamic rotation speed of the base is dynamically adjusted so that the growth rate of the center / edge region of the target epitaxial layer conforms to the target growth rate.

2. The method for dynamically controlling the growth rate of the center / edge region in a semiconductor epitaxial process according to claim 1, characterized in that, The dynamic rotational speed of the base is R = K × S, where S is the initial rotational speed of the base and K is an introduced dynamic coefficient used to control the rotational speed and direction of rotation of the base. When K < 0, the base rotates in the opposite direction.

3. The method for dynamically controlling the growth rate of the center / edge region in a semiconductor epitaxial process according to claim 2, characterized in that, By dynamically controlling the rotation speed and direction of the base through the dynamic coefficient K, the gas from the transverse airflow port of the epitaxial machine is dynamically introduced into the center or edge region of the target epitaxial layer, forming a competitive reaction with the silicon source gas introduced through the main air inlet, thereby dynamically controlling the growth rate of the center / edge region of the target epitaxial layer.

4. The method for dynamically controlling the growth rate of the center / edge region in a semiconductor epitaxial process according to claim 3, characterized in that, The main air inlet is supplied with the first carrier gas, silicon source gas, and dopant gas, while the transverse airflow port is supplied with the second carrier gas and hydrogen chloride gas.

5. The method for dynamically controlling the growth rate of the center / edge region of a semiconductor epitaxial process according to claim 4, characterized in that, The first and second carrier gases are hydrogen, the silicon source gas is dichlorosilane or trichlorosilane, and the doping gas is diborane.

6. The method for dynamically controlling the growth rate of the center / edge region of a semiconductor epitaxial process according to any one of claims 2 to 5, characterized in that, When the rotation direction of the base is opposite to the gas direction of the transverse airflow port, the gas in the transverse airflow port is introduced into the central region of the target epitaxial layer. The growth rate of the central region of the target epitaxial layer is dynamically controlled by controlling the rotation speed of the base. When the rotation direction of the base is the same as the gas direction of the transverse airflow port, the gas in the transverse airflow port is introduced into the edge region of the target epitaxial layer. The growth rate of the target epitaxial layer edge region is dynamically controlled by controlling the rotation speed of the base.

7. The method for dynamically controlling the growth rate of the center / edge region in a semiconductor epitaxial process according to claim 1, characterized in that, The target epitaxial layer is an N-type single-crystal silicon epitaxial film or a P-type single-crystal silicon epitaxial film.

8. The method for dynamically controlling the growth rate of the center / edge region in a semiconductor epitaxial process according to claim 1, characterized in that, The actual rotational speed of the epitaxial machine base is periodically obtained. If the ratio of the infrared radiation sensor values ​​at the center and edge of the target epitaxial layer does not match the preset first mapping relationship with the actual rotational speed of the base, the epitaxial machine is abnormal.

9. A system for dynamically controlling the growth rate of the center / edge region in a semiconductor epitaxial process, characterized in that, include: The first mapping module is used to acquire the ratio of the central and edge infrared radiation sensors during the growth of the target epitaxial layer, and determine the dynamic rotation speed of the base based on a preset first mapping relationship; wherein, the first mapping relationship is defined as the correspondence between the ratio of the central and edge infrared radiation sensors and the dynamic rotation speed of the epitaxial machine base. The second mapping module is used to determine the growth rate of the target epitaxial layer center / edge region based on the determined dynamic rotation speed of the base and the preset second mapping relationship; wherein, the second mapping relationship is defined as the correspondence between the growth rate of the target epitaxial layer center / edge region and the dynamic rotation speed of the base; The dynamic control module is used to obtain the target growth rate of the center / edge region of the target epitaxial layer, and dynamically control the dynamic rotation speed of the base in combination with the determined growth rate of the center / edge region of the target epitaxial layer and the second mapping relationship, so that the growth rate of the center / edge region of the target epitaxial layer conforms to the target growth rate.

10. An epitaxial machine, characterized in that, Includes a controller configured to perform a method for dynamically controlling the growth rate of the center / edge region of a semiconductor epitaxial process as described in any one of claims 1 to 8.

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