A semiconductor annealing method, annealing device and annealing system

Abstract

The invention relates to the technical field of semiconductor device preparation, and specifically discloses a semiconductor annealing method, an annealing device and an annealing system, wherein the method comprises the following steps: obtaining surface temperature information of a SiC semiconductor sheet; performing microwave heating on the SiC semiconductor sheet using a heating temperature lower than the melting point temperature of single crystal silicon; when the surface temperature information reaches a preset first temperature threshold, performing mobile electron beam heating on the SiC semiconductor sheet until the annealing treatment of the SiC semiconductor sheet is completed; the method uses microwave heating to heat the SiC semiconductor sheet to the first temperature threshold, which can reduce the temperature required for the annealing treatment of the SiC semiconductor sheet to an expected range, and then uses electron beam heating to perform precise temperature-controlled annealing treatment on the SiC semiconductor sheet, which can reduce the annealing treatment temperature and improve the annealing treatment efficiency while ensuring the annealing treatment effect.

Description

Technical Field

[0001] The present application relates to the technical field of semiconductor device preparation, and in particular to a semiconductor annealing method, an annealing device and an annealing system. Background Art

[0002] In the prior art, after the semiconductor sheet is prepared, it needs to be annealed, but the annealing temperature is relatively high, which can easily cause damage to the surface elements or protective layer. For example, for SiC semiconductor sheets prepared by ion implantation, the rapid annealing temperature is generally above 1600°C. The melting point of Si is 1400°C, and the melting point of SiC is 1700°C. The annealing of the SiC semiconductor sheet needs to be heated within the temperature range of 1600°C to 2000°C for a period of time. Although the annealing process can activate ions, it may cause the volatilization of Si elements on the surface of the material and damage the original SiC wafer. The main method to avoid this is to plate a protective layer on the surface of the SiC semiconductor sheet. However, above 1600°C, the protective layer material is not stable enough, has poor protection, and is also prone to damage.

[0003] There is currently no effective technical solution to the above problems. Summary of the invention

[0004] The purpose of the present application is to provide a semiconductor annealing method, an annealing device and an annealing system, which can reduce the annealing temperature, improve the annealing efficiency and solve the problem of damage to the surface elements or protective layer of SiC semiconductor sheets while ensuring the annealing effect.

[0005] In a first aspect, the present application provides a semiconductor annealing method for annealing a SiC semiconductor sheet, the method comprising the following steps:

[0006] Acquiring surface temperature information of the SiC semiconductor sheet;

[0007] Performing microwave heating on the SiC semiconductor sheet;

[0008] When the surface temperature information reaches a preset first temperature threshold, the SiC semiconductor sheet is subjected to mobile electron beam heating at a heating temperature lower than the melting point of single crystal silicon until the annealing process of the SiC semiconductor sheet is completed.

[0009] The semiconductor annealing method of the present application combines microwave heating and electron beam heating to anneal SiCSiC semiconductor sheets, which can reduce the annealing temperature while ensuring the annealing effect, so that the temperature required for annealing is lower than the melting point of single crystal silicon, and solves the problem of damage to the surface elements or protective layer of the SiC semiconductor sheet.

[0010] The semiconductor annealing method, wherein the position of the electron beam heating corresponds to the position of the surface temperature information, and the step of performing mobile electron beam heating on the SiC semiconductor sheet at a heating temperature lower than the melting point of single crystal silicon until the annealing of the SiC semiconductor sheet is completed comprises:

[0011] locally heating the SiC semiconductor sheet using an electron beam;

[0012] When the surface temperature information reaches a preset second temperature threshold, the local heating position of the electron beam is switched according to a preset annealing path, and the second temperature threshold is less than the melting point temperature of the single crystal silicon.

[0013] The semiconductor annealing method, wherein the second temperature threshold is 1.5-3 times the first temperature threshold.

[0014] In the semiconductor annealing method of this example, the second temperature threshold is designed to be 1.5-3 times the first temperature threshold, which can avoid the microwave heating temperature rise affecting the annealing effect, that is, the annealing process is carried out while ensuring that there is a sufficient temperature difference between the first temperature threshold and the second temperature threshold, so as to avoid the heat generated by microwave heating and the heat generated by electron beam heating being superimposed on each other, thereby avoiding the instability of microwave heating causing a large temperature difference and affecting the annealing effect.

[0015] In a second aspect, the present application further provides a semiconductor annealing device for annealing a SiC semiconductor sheet using the semiconductor annealing method provided in the first aspect, wherein the semiconductor annealing device comprises:

[0016] Annealing chamber;

[0017] A supporting mechanism, fixed in the annealing chamber, for supporting the SiC semiconductor sheet;

[0018] A temperature measuring mechanism, arranged above the supporting mechanism, for measuring the surface temperature information of the SiC semiconductor sheet;

[0019] A microwave heating mechanism, disposed below the supporting mechanism, for performing microwave heating on the SiC semiconductor sheet;

[0020] An electron beam heating mechanism, disposed above the supporting mechanism, for locally heating the surface of the SiC semiconductor sheet using an electron beam;

[0021] The moving mechanism is used to switch the local heating position of the electron beam heating mechanism on the surface of the SiC semiconductor sheet to achieve mobile electron beam heating.

[0022] The semiconductor annealing device of the present application combines a microwave heating mechanism and an electron beam heating mechanism to perform annealing treatment on SiC semiconductor sheets by using two heating means, namely microwave heating and electron beam heating. The annealing treatment temperature can be reduced while ensuring the annealing treatment effect, so that the temperature required for the annealing treatment is lower than the melting point of single crystal silicon, and the problem of damage to the surface elements or protective layer of the SiC semiconductor sheet is solved.

[0023] The semiconductor annealing device, wherein the moving mechanism comprises:

[0024] A first rotating assembly, mounted on the supporting mechanism, for driving the SiC semiconductor sheet to rotate;

[0025] The first linear driving component is connected to the electron beam heating mechanism and is used to drive the electron beam heating mechanism to perform horizontal displacement.

[0026] In the semiconductor annealing device of this example, the first rotating component can drive the SiC semiconductor sheet to rotate a specific angle according to the annealing process, and is combined with the first linear driving component to drive the electron beam heating mechanism to move a specific distance in a direction perpendicular to the rotation axis of the SiC semiconductor sheet according to the annealing process, so that the electron beam can bombard various positions on the surface of the SiC semiconductor sheet. According to the composition of the above-mentioned moving mechanism, an annealing path that travels across the surface of the SiC semiconductor sheet can be designed to ensure that the SiC semiconductor sheet as a whole can successfully complete the annealing process.

[0027] The semiconductor annealing device, wherein the moving mechanism comprises:

[0028] A longitudinal driving assembly, connected to the electron beam heating mechanism, and used to drive the electron beam heating mechanism to perform longitudinal horizontal displacement;

[0029] The transverse driving assembly is connected to the longitudinal driving assembly and is used to drive the electron beam heating mechanism to perform transverse horizontal displacement.

[0030] The semiconductor annealing device, wherein the moving mechanism comprises:

[0031] A second rotating assembly, mounted on the supporting mechanism, for driving the SiC semiconductor sheet to rotate;

[0032] The second linear drive assembly is connected to the second rotating assembly and is used to drive the second rotating assembly to perform horizontal displacement.

[0033] The semiconductor annealing device, wherein the temperature measuring position of the temperature measuring mechanism is aligned with the local heating position of the electron beam heating mechanism.

[0034] The semiconductor annealing device further comprises a loading chamber for storing the SiC semiconductor sheet and a loading and unloading robot for transferring the SiC semiconductor sheet.

[0035] In a third aspect, the present application further provides a semiconductor annealing system for annealing a SiC semiconductor sheet, the semiconductor annealing system comprising a semiconductor annealing device and a controller, the semiconductor annealing device comprising:

[0036] Annealing chamber;

[0037] A supporting mechanism, fixed in the annealing chamber, for supporting the SiC semiconductor sheet;

[0038] A temperature measuring mechanism, arranged above the supporting mechanism, for measuring the surface temperature information of the SiC semiconductor sheet;

[0039] A microwave heating mechanism, disposed below the supporting mechanism, for performing microwave heating on the SiC semiconductor sheet;

[0040] An electron beam heating mechanism, disposed above the supporting mechanism, for locally heating the surface of the SiC semiconductor sheet using an electron beam;

[0041] A moving mechanism, used for switching the local heating position of the electron beam heating mechanism on the surface of the SiC semiconductor sheet to achieve mobile electron beam heating;

[0042] The controller is electrically connected to the temperature measuring mechanism, the microwave heating mechanism, the electron beam heating mechanism and the moving mechanism;

[0043] The controller is used to obtain the surface temperature information;

[0044] The controller is also used to control the microwave heating mechanism to perform microwave heating on the SiC semiconductor sheet;

[0045] The controller is also used to control the electron beam heating mechanism and the moving mechanism to cooperate to perform mobile electron beam heating on the SiC semiconductor sheet using a heating temperature lower than the melting point of single crystal silicon when the surface temperature information reaches a preset first temperature threshold, until the annealing process of the SiC semiconductor sheet is completed.

[0046] The semiconductor annealing system of the present application combines a microwave heating mechanism and an electron beam heating mechanism to perform annealing treatment on SiC semiconductor sheets by using two heating means, namely microwave heating and electron beam heating. The annealing treatment temperature can be reduced while ensuring the annealing treatment effect, so that the temperature required for the annealing treatment is lower than the melting point of single crystal silicon, and the problem of damage to the surface elements or protective layer of the SiC semiconductor sheet is solved.

[0047] As can be seen from the above, the present application provides a semiconductor annealing method, annealing device and annealing system, wherein the annealing method combines microwave heating and electron beam heating to anneal SiC semiconductor sheets. The SiC semiconductor sheet is heated to a first temperature threshold by microwave heating, which can reduce the temperature required for annealing the SiC semiconductor sheet to below the melting point of single crystal silicon. Electron beam heating with a heating temperature lower than the melting point of single crystal silicon is then used to perform precise temperature-controlled annealing on the SiC semiconductor sheet. The annealing temperature can be reduced and the annealing efficiency can be improved while ensuring the annealing effect. The problem of damage to the surface elements or protective layer of the SiC semiconductor sheet is solved, and the protective layer on the surface of the SiC semiconductor sheet can even be omitted during the annealing process. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 A flow chart of a semiconductor annealing method provided in an embodiment of the present application.

[0049] Figure 2 A schematic structural diagram of a preferred implementation scheme of a semiconductor annealing device provided in an embodiment of the present application, in which a portion of the outer wall of the annealing chamber is hidden.

[0050] Figure 3 It is a schematic diagram of the top view of the structure of the first rotating component.

[0051] Figure 4 A schematic structural diagram of another preferred implementation scheme of the semiconductor annealing device provided in an embodiment of the present application, in which a portion of the outer wall of the annealing chamber is hidden.

[0052] Figure 5 A schematic structural diagram of another preferred implementation manner of the semiconductor annealing device provided in an embodiment of the present application, in which a portion of the outer wall of the annealing chamber is hidden.

[0053] Figure 6 This is a schematic diagram of the forward cross-sectional structure of a semiconductor annealing device provided in an embodiment of the present application.

[0054] Figure 7 A schematic diagram of the connection structure of the electrical control components of the semiconductor annealing system provided in an embodiment of the present application.

[0055] Figure numerals: 1. Annealing chamber; 2. Supporting mechanism; 3. Temperature measuring mechanism; 4. Microwave heating mechanism; 5. Electron beam heating mechanism; 6. Moving mechanism; 7. Loading cavity; 8. Loading and unloading robot; 9. Controller; 61. First rotating assembly; 62. First linear drive assembly; 63. Longitudinal drive assembly; 64. Transverse drive assembly; 65. Second rotating assembly; 66. Second linear drive assembly. DETAILED DESCRIPTION

[0056] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application claimed for protection, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the present application.

[0057] It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings. At the same time, in the description of this application, the terms "first", "second", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0058] First, please refer to Figure 1 , Figure 1 A semiconductor annealing method in some embodiments of the present application is used to anneal a SiC semiconductor sheet, and the method includes the following steps:

[0059] S1. Obtaining surface temperature information of SiC semiconductor sheet;

[0060] Specifically, the surface temperature information is the temperature data of a local area or a certain position on the surface of the SiC semiconductor sheet, and can be collected remotely through a temperature measuring mechanism such as an infrared probe.

[0061] S2, performing microwave heating on the SiC semiconductor sheet;

[0062] Specifically, microwave heating mainly utilizes the oscillation of dipoles in an electric field to generate heat through friction and then heat the SiC semiconductor sheet. It is a regional heating method. In the embodiment of the present application, step S2 should be understood as heating the SiC semiconductor sheet as a whole.

[0063] S3. When the surface temperature information reaches a preset first temperature threshold, the SiC semiconductor sheet is subjected to mobile electron beam heating at a heating temperature lower than the melting point of single crystal silicon until the annealing process of the SiC semiconductor sheet is completed.

[0064] Specifically, SiC semiconductor sheets are dielectrics. When they are heated by microwaves, the dielectric absorbs microwaves and produces a dielectric relaxation effect, that is, the reactant molecules lag behind the oscillation frequency of the electromagnetic wave, resulting in a relaxation phenomenon, which increases the collision frequency within the material molecules, reduces the reaction activation energy, increases the reaction rate, and then reduces the reaction temperature. Therefore, the temperature conditions required for the annealing of the SiC semiconductor sheet can be reduced after the treatment of step S2. On this basis, step S3 uses a heating temperature lower than the melting point of single crystal silicon to perform mobile electron beam heating on the SiC semiconductor sheet, which can reduce the temperature conditions. The SiC semiconductor sheet is annealed gradually, which reduces the process requirements for the annealing treatment, improves the annealing treatment efficiency (i.e., reduces the time required for the temperature to rise), and solves the problem of damage to the surface elements or protective layer of the SiC semiconductor sheet. The heating temperature of the electron beam heating is set to be lower than the melting point of single crystal silicon, i.e., lower than 1400°C, and lower than the melting point of SiC of 1700°C, so there is no damage to the Si element and SiC, so that the SiC semiconductor sheet can be smoothly and fully annealed without the need for surface coating of a protective layer, and damage to the surface of the SiC semiconductor sheet can be effectively avoided.

[0065] More specifically, microwave heating itself cannot precisely control the dipoles, and has the disadvantages of poor heating stability, poor uniformity, and long annealing holding time. If microwave heating is directly used to complete the entire annealing process, it often leads to uneven annealing of the SiC semiconductor sheet as a whole, which restricts the product processing quality. Therefore, the method of the embodiment of the present application adopts microwave heating in combination with electron beam heating to anneal the SiC semiconductor sheet, and uses microwave heating to reduce the temperature conditions required for annealing the SiC semiconductor sheet, and then uses electron beam heating to perform mobile and precise heating treatment on the SiC semiconductor sheet, so as to accurately anneal the SiC semiconductor sheet under the premise of reducing the temperature required for electron beam heating annealing to below the melting point of single crystal silicon.

[0066] More specifically, it can be seen from the foregoing that microwave heating is used in the embodiment of the present application to reduce the temperature conditions required for electron beam heating annealing treatment. Therefore, microwave heating only needs to heat the SiC semiconductor sheet to a preset first temperature threshold. The preset first temperature threshold is determined based on simulation or experiment. Its design requirement is to reduce the temperature deviation required for electron beam heating annealing treatment to a temperature that will not damage the surface elements or protective layer of the SiC semiconductor sheet. Generally, the temperature required for electron beam heating annealing treatment can be reduced by more than 500°C to adjust the electron beam heating temperature to below the melting point of single crystal silicon.

[0067] The semiconductor annealing method of the embodiment of the present application combines microwave heating and electron beam heating to anneal the SiC semiconductor sheet, wherein the SiC semiconductor sheet is heated to a first temperature threshold by microwave heating, which can reduce the temperature required for annealing the SiC semiconductor sheet to below the melting point of single crystal silicon, and then the SiC semiconductor sheet is precisely temperature-controlled annealing by electron beam heating at a heating temperature lower than the melting point of single crystal silicon, which can reduce the annealing temperature and improve the annealing efficiency while ensuring the annealing effect, and solve the problem of damage to the surface elements or protective layer of the SiC semiconductor sheet, and even the protective layer on the surface of the SiC semiconductor sheet can be omitted during the annealing process.

[0068] In some preferred embodiments, the position of the electron beam heating corresponds to the position of the surface temperature information, and the step of performing mobile electron beam heating on the SiC semiconductor sheet at a heating temperature lower than the melting point of single crystal silicon until the annealing of the SiC semiconductor sheet is completed comprises:

[0069] S31, locally heating the SiC semiconductor sheet using an electron beam;

[0070] Specifically, this step generally uses an electron beam heating mechanism such as an electron gun to generate an electron beam to bombard a specific position on the surface of the SiC semiconductor sheet to locally heat the SiC semiconductor sheet.

[0071] S32. When the surface temperature information reaches a preset second temperature threshold, the local heating position of the electron beam is switched according to a preset annealing path, and the second temperature threshold is less than the melting point temperature of the single crystal silicon.

[0072] Specifically, the preset second temperature threshold is the temperature required for electron beam heating annealing treatment of the SiC semiconductor sheet after microwave heating treatment. The second temperature threshold is determined based on simulation or experiment. Generally, the higher the first temperature threshold, the smaller the second temperature threshold. Therefore, the second temperature threshold and the first temperature threshold should be set in correlation with each other, that is, the first temperature threshold needs to adjust the electron beam annealing temperature to below 1400°C so that the second temperature threshold can be set below 1400°C.

[0073] More specifically, the annealing path is a heating annealing treatment route set according to the processing technology, which is used to guide the movement path of the electron beam relative to the SiC semiconductor sheet. In the embodiment of the present application, it refers to the movement path of the electron beam relative to the surface of the SiC semiconductor sheet. Therefore, the setting of the annealing path should completely cover all parts of the SiC semiconductor sheet that need to be annealed, so that the electron beam can complete the annealing treatment of the entire SiC semiconductor sheet after completing the heating treatment of the SiC semiconductor sheet according to the annealing path.

[0074] More specifically, in general, the annealing process has certain annealing holding time requirements. Therefore, corresponding to the annealing process with the annealing holding time requirements, step S32 should be understood as: when the surface temperature information reaches the preset second temperature threshold, the local heating position of the electron beam is switched according to the preset annealing path with a delay; the delay interval must meet the annealing holding time.

[0075] In some preferred embodiments, the second temperature threshold is 1.5-3 times the first temperature threshold.

[0076] Specifically, the second temperature threshold is designed to be 1.5-3 times the first temperature threshold, which can avoid the microwave heating temperature rising affecting the annealing effect, that is, the annealing treatment is carried out while ensuring that the first temperature threshold and the second temperature threshold have a sufficient temperature difference, so as to avoid the heat generated by microwave heating and the heat generated by electron beam heating being superimposed on each other, thereby avoiding the instability of microwave heating causing a large temperature difference and affecting the annealing effect.

[0077] In some preferred embodiments, the first temperature threshold is 400-600°C, and the second temperature threshold is 900-1200°C; the specific setting values ​​of the first temperature threshold and the second temperature threshold are set depending on the processing efficiency and equipment parameters, and must meet the conditions that the first temperature threshold is 400-600°C, the second temperature threshold is 900-1200°C, and the second temperature threshold is 1.5-3 times the first temperature threshold.

[0078] In the embodiment of the present application, the first temperature threshold is preferably 500°C, and the second temperature threshold is preferably 1200°C; after the SiC semiconductor sheet is subjected to microwave treatment using the first temperature threshold of 500°C, the electron beam heating annealing temperature of the SiC semiconductor sheet can actually drop to around 1100°C, but in order to improve the efficiency and effect of the annealing treatment, the second temperature threshold is still set to 1200°C, which is higher than 1100°C, to ensure that the SiC semiconductor sheet can complete the annealing treatment efficiently and with high quality.

[0079] Second, please refer to Figure 2-Figure 6 , Figure 2-Figure 6 A semiconductor annealing device is provided in some embodiments of the present application, and is used to anneal a SiC semiconductor sheet using the semiconductor annealing method provided in the first aspect. The semiconductor annealing device includes:

[0080] Annealing chamber 1;

[0081] A supporting mechanism 2, fixed in the annealing chamber 1, for supporting the SiC semiconductor sheet;

[0082] The temperature measuring mechanism 3 is arranged above the supporting mechanism 2 and is used to measure the surface temperature information of the SiC semiconductor sheet;

[0083] A microwave heating mechanism 4 is arranged below the supporting mechanism 2 and is used for performing microwave heating on the SiC semiconductor sheet;

[0084] The electron beam heating mechanism 5 is arranged above the supporting mechanism 2 and is used to locally heat the surface of the SiC semiconductor sheet by using an electron beam;

[0085] The moving mechanism 6 is used to switch the local heating position of the electron beam heating mechanism 5 on the surface of the SiC semiconductor sheet to achieve mobile electron beam heating.

[0086] Specifically, the semiconductor annealing apparatus is a hardware device for implementing the semiconductor annealing method provided in the first aspect.

[0087] The semiconductor annealing device of the embodiment of the present application combines a microwave heating mechanism 4 and an electron beam heating mechanism 5 to perform annealing treatment on the SiC semiconductor sheet by using microwave heating and electron beam heating. The SiC semiconductor sheet is heated to a first temperature threshold by using microwave heating, which can reduce the temperature required for annealing treatment of the SiC semiconductor sheet to below the melting point of single crystal silicon. Then, the SiC semiconductor sheet is subjected to precise temperature-controlled annealing treatment by using electron beam heating whose heating temperature is lower than the melting point of single crystal silicon. This can reduce the annealing temperature and improve the annealing efficiency while ensuring the annealing effect, and solve the problem of damage to the surface elements or protective layer of the SiC semiconductor sheet.

[0088] SiC semiconductor sheets generally include a substrate and a crystal plane on the substrate. The object of annealing treatment is mainly the crystal plane. Therefore, in the embodiment of the present application, the semiconductor material is arranged on the supporting mechanism 2 with the crystal plane facing upward, and the microwave heating mechanism 4 is used to perform microwave heating on the bottom surface of the SiC semiconductor sheet, so that during the microwave heating treatment, the heat of the SiC semiconductor sheet is transferred from bottom to top, and the electron beam heating mechanism 5 is arranged above the supporting mechanism 2, which can directly heat the crystal plane of the SiC semiconductor sheet and realize the heating annealing treatment with precise temperature control.

[0089] In some preferred embodiments, the supporting mechanism 2 is a workbench for supporting the SiC semiconductor sheet, and has an opening at the bottom thereof for the microwave heating mechanism 4 to perform microwave heating on the SiC semiconductor sheet.

[0090] In some preferred embodiments, the moving mechanism 6 is used to drive the electron beam heating mechanism 5 to move and / or drive the SiC semiconductor sheet on the supporting mechanism 2 to move, so as to switch the local heating position of the electron beam heating mechanism 5 on the surface of the SiC semiconductor sheet to achieve mobile electron beam heating.

[0091] like Figure 2 and Figure 3 As shown, in some preferred embodiments, the moving mechanism 6 includes:

[0092] The first rotating assembly 61 is mounted on the supporting mechanism 2 and is used to drive the SiC semiconductor sheet to rotate;

[0093] The first linear driving component 62 is connected to the electron beam heating mechanism 5 and is used to drive the electron beam heating mechanism 5 to perform horizontal displacement.

[0094] In this embodiment, the first rotating component 61 can drive the SiC semiconductor sheet to rotate a specific angle according to the annealing process, and is combined with the first linear driving component 62 to drive the electron beam heating mechanism 5 to move a specific distance in a direction perpendicular to the rotation axis of the SiC semiconductor sheet according to the annealing process, so that the electron beam can bombard various positions on the surface of the SiC semiconductor sheet. According to the composition of the above-mentioned moving mechanism 6, an annealing path that travels across the surface of the SiC semiconductor sheet can be designed to ensure that the SiC semiconductor sheet as a whole can successfully complete the annealing process.

[0095] More specifically, in this embodiment, the annealing path can be a spiral route, or a route composed of multiple concentric circles connected by radial lines, or a route composed of multiple straight lines radially scattered from the rotation axis of the SiC semiconductor sheet; in the embodiment of the present application, the annealing path is preferably a route composed of multiple concentric circles connected by radial lines, so that the electron beam heating mechanism 5 can cooperate with the first rotating component 61 to operate simultaneously to heat and anneal the SiC semiconductor sheet, that is, in this embodiment, a circular area is used as a local heating position for heating.

[0096] Preferably, the first rotating assembly 61 can be a general rotating driving device, such as a rotating motor, a rotating cylinder, etc. In the embodiment of the present application, Figure 3 As shown, the first rotating assembly 61 preferably includes:

[0097] The driving gear and the driven gear ring are meshed with the outer side of the driven gear ring. The driving gear is driven to rotate by a driving motor (not shown in the figure), thereby driving the driven gear ring to rotate. The driven gear ring is arranged on the supporting mechanism 2 and is used to cooperate with the supporting mechanism 2 to support and drive the SiC semiconductor sheet to rotate.

[0098] More preferably, a clamping block is provided on the surface of the driven gear ring, and the SiC semiconductor sheet has a clamping mouth that cooperates with the clamping block, so it can rotate according to the driven gear ring.

[0099] Preferably, the first linear drive component 62 is an electrically controlled linear drive mechanism, such as a pneumatic cylinder, an oil cylinder, a ball screw, an electric linear slide, etc. In the embodiment of the present application, it is preferably an electric linear slide, which can accurately control the moving position of the electron beam heating mechanism 5 to ensure accurate adjustment of the local heating position.

[0100] More specifically, in this embodiment, when executing step S2, the first rotating assembly 61 drives the SiC semiconductor sheet to rotate continuously, which can make the microwave heating effect more uniform and make the subsequent annealing treatment effect better.

[0101] like Figure 4 As shown, in some other preferred embodiments, the moving mechanism 6 includes:

[0102] A longitudinal driving assembly 63, connected to the electron beam heating mechanism 5, and used to drive the electron beam heating mechanism 5 to perform longitudinal horizontal displacement;

[0103] The transverse driving assembly 64 is connected to the longitudinal driving assembly 63 and is used to drive the electron beam heating mechanism 5 to perform transverse horizontal displacement.

[0104] In this embodiment, the coordinated movement of the longitudinal drive assembly 63 and the transverse drive assembly 64 can change the horizontal position of the electron beam heating mechanism 5, so that the electron beam heating mechanism 5 can be moved arbitrarily in a horizontal plane. According to the composition of the above-mentioned moving mechanism 6, an annealing path that travels across the surface of the SiC semiconductor sheet can be designed to ensure that the entire SiC semiconductor sheet can successfully complete the annealing process.

[0105] More specifically, in this embodiment, the annealing path can be a spiral route, or a route composed of multiple concentric circles connected by radial lines, or a route composed of multiple straight lines radially scattered from the rotation axis of the SiC semiconductor sheet, or a serpentine route; in the embodiment of the present application, the annealing path is preferably a serpentine route, which can enable the SiC semiconductor sheet to undergo comprehensive and orderly annealing treatment under the simplified control logic of the longitudinal drive component 63 and the transverse drive component 64.

[0106] Preferably, the longitudinal drive assembly 63 and the transverse drive assembly 64 are both electrically controlled linear drive mechanisms, such as air cylinders, oil cylinders, ball screws, electric linear slides, etc. In the embodiment of the present application, electric linear slides are preferred, which can accurately control the moving position of the electron beam heating mechanism 5 to ensure accurate adjustment of the local heating position.

[0107] like Figure 5 As shown, in some other preferred embodiments, the moving mechanism 6 includes:

[0108] The second rotating assembly 65 is mounted on the supporting mechanism 2 and is used to drive the SiC semiconductor sheet to rotate;

[0109] The second linear drive assembly 66 is connected to the second rotating assembly 65 and is used to drive the second rotating assembly 65 to perform horizontal displacement.

[0110] In this embodiment, the second rotating component 65 is preferably consistent with the first rotating component 61 and is installed on the movable end of the second linear drive component 66. The electron beam heating mechanism 5 is fixed in position. This embodiment changes the position of the SiC semiconductor sheet relative to the electron beam heating mechanism 5 by coordinating the movement of the second rotating component 65 and the second linear drive component 66 to achieve switching of the local heating position.

[0111] In some preferred embodiments, the temperature measuring position of the temperature measuring mechanism 3 is aligned with the local heating position of the electron beam heating mechanism 5 .

[0112] Specifically, the temperature measuring mechanism 3 is preferably installed on one side of the output end of the electron beam heating mechanism 5, and the installation angle is determined according to the distance between the SiC semiconductor sheet and the output end of the electron beam heating mechanism 5, so that the temperature measuring position of the temperature measuring mechanism 3 is aligned with the local heating position of the electron beam heating mechanism 5, so that when executing step S3, the surface temperature information can directly reflect the heating progress of the electron beam heating mechanism 5.

[0113] In some preferred embodiments, the annealing chamber 1 is a closed chamber during the annealing process, which is filled with a protective gas (such as argon or nitrogen) to ensure that the annealing process can be carried out stably. Therefore, the annealing chamber 1 should be connected to a gas regulating component (not shown) for inputting a protective gas.

[0114] In some preferred embodiments, Figure 6 As shown, the semiconductor annealing device further includes a loading chamber 7 for storing SiC semiconductor sheets and a loading and unloading robot 8 for transferring SiC semiconductor sheets.

[0115] Specifically, the loading chamber 7 is communicated with the annealing chamber 1 and is used for storing SiC semiconductor sheets that have not been annealed and SiC semiconductor sheets that have been annealed.

[0116] More specifically, the loading and unloading robot 8 is used to transfer the SiC semiconductor sheets that have not been annealed in the loading chamber 7 to the supporting mechanism 2 for annealing, and is also used to transfer the SiC semiconductor sheets that have been annealed in the supporting mechanism 2 to the loading chamber 7 for storage.

[0117] More specifically, the device of the embodiment of the present application is provided with a loading chamber 7 and a loading and unloading robot 8 to realize large-scale and continuous annealing treatment.

[0118] In some preferred embodiments, the loading chamber 7 is a quartz chamber, and an electric gate valve is provided at the connection between the loading chamber 7 and the annealing chamber 1. When the semiconductor annealing device of the embodiment of the present application is used, a gas regulating component is required to evacuate the loading chamber 7 and fill it with protective gas.

[0119] Third, please refer to Figure 7 , Figure 7 A semiconductor annealing system is provided in some embodiments of the present application, which is used to anneal SiC semiconductor sheets. The semiconductor annealing system includes the semiconductor annealing device and the controller 9. The semiconductor annealing device includes:

[0120] Annealing chamber 1;

[0121] A supporting mechanism 2, fixed in the annealing chamber 1, for supporting the SiC semiconductor sheet;

[0122] The temperature measuring mechanism 3 is arranged above the supporting mechanism 2 and is used to measure the surface temperature information of the SiC semiconductor sheet;

[0123] A microwave heating mechanism 4 is arranged below the supporting mechanism 2 and is used for performing microwave heating on the SiC semiconductor sheet;

[0124] The electron beam heating mechanism 5 is arranged above the supporting mechanism 2 and is used to locally heat the surface of the SiC semiconductor sheet by using an electron beam;

[0125] A moving mechanism 6, used for switching the local heating position of the electron beam heating mechanism 5 on the surface of the SiC semiconductor sheet to achieve mobile electron beam heating;

[0126] The controller 9 is electrically connected to the temperature measuring mechanism 3, the microwave heating mechanism 4, the electron beam heating mechanism 5 and the moving mechanism 6;

[0127] The controller 9 is used to obtain surface temperature information;

[0128] The controller 9 is also used to control the microwave heating mechanism 4 to perform microwave heating on the SiC semiconductor sheet;

[0129] The controller 9 is also used to control the electron beam heating mechanism 5 and the moving mechanism 6 to cooperate with each other to perform mobile electron beam heating on the SiC semiconductor sheet using a heating temperature lower than the melting point of single crystal silicon when the surface temperature information reaches a preset first temperature threshold, until the annealing process of the SiC semiconductor sheet is completed.

[0130] The semiconductor annealing system of the embodiment of the present application combines a microwave heating mechanism 4 and an electron beam heating mechanism 5 to perform annealing treatment on the SiC semiconductor sheet by using microwave heating and electron beam heating. The SiC semiconductor sheet is heated to a first temperature threshold by using microwave heating, which can reduce the temperature required for annealing treatment of the SiC semiconductor sheet to below the melting point of single crystal silicon. Then, the SiC semiconductor sheet is subjected to precise temperature-controlled annealing treatment by using electron beam heating whose heating temperature is lower than the melting point of single crystal silicon. This can reduce the annealing temperature and improve the annealing efficiency while ensuring the annealing effect, and solve the problem of damage to the surface elements or protective layer of the SiC semiconductor sheet.

[0131] In some preferred embodiments, the temperature measuring position of the temperature measuring mechanism 3 is aligned with the local heating position of the electron beam heating mechanism 5, and the controller 9 controls the electron beam heating mechanism 5 and the moving mechanism 6 to cooperate to perform mobile electron beam heating on the SiC semiconductor sheet. The process includes:

[0132] Controlling the electron beam heating mechanism 5 to locally heat the SiC semiconductor sheet using the electron beam;

[0133] When the surface temperature information reaches a preset second temperature threshold, the moving mechanism 6 is controlled to switch the local heating position of the electron beam according to a preset annealing path.

[0134] In some preferred embodiments, the second temperature threshold is 1.5-3 times the first temperature threshold.

[0135] Example 1

[0136] To more clearly illustrate the embodiments of the present application, Figure 6 The semiconductor annealing device shown performs annealing on a SiC semiconductor sheet (hereinafter referred to as SiC sheet) generated by ion implantation of SiC, and the process is as follows:

[0137] After the loading cavity 7 and the annealing chamber 1 are filled with protective gas, the loading and unloading robot 8 is used to move the SiC wafer to the supporting mechanism 2, and the controller 9 controls the first rotating assembly 61 and the microwave heating mechanism 4 to start, so that the SiC wafer continues to rotate, and the microwave heating mechanism 4 is used to perform microwave heating on the SiC wafer, wherein the microwave frequency of the microwave heating mechanism 4 is 2.45 GHz, and the ion implantation type, ion implantation degree, and thickness of the SiC wafer will affect the efficiency of microwave heating.

[0138] During the microwave heating process, the surface temperature of the SiC wafer is measured using an infrared probe arranged on the output end of the electron gun. When the top surface temperature of the SiC wafer rises to 500°C (a preset first temperature threshold), the controller 9 controls the microwave heating mechanism 4 to reduce the microwave frequency so that the top surface temperature of the SiC wafer is maintained at around 500°C.

[0139] The controller 9 controls the electron gun to start heating the SiC sheet, and the first rotating assembly 61 continues to drive the SiC sheet to rotate, wherein the electron beam energy density is 0.2-0.4 J / cm 2 The electron beam spot has a radius of 2 mm. 2 circle (the radius of the focusing coil can be changed according to the use requirements); in this embodiment, the annealing path is a plurality of circular routes coaxial with the rotating axis of the SiC wafer, and the electron gun performs heating annealing treatment on the plurality of circular routes in sequence from the inside to the outside, that is, after completing the heating annealing treatment on the innermost circular route, the electron gun moves to the next circular route through the first linear drive component 62 to perform heating annealing treatment on the SiC wafer, and the switching is adjusted so that the temperature of each position of the SiC wafer on the corresponding circular route reaches 1200°C (the preset second temperature threshold value); when the electron gun completes the heating annealing treatment on the outermost circular route of the SiC wafer, it indicates that the heating annealing treatment of the SiC wafer as a whole is completed, and the controller 9 turns off the electron gun and the microwave heating mechanism 4 to make the SiC wafer drop to a suitable temperature, and then the loading and unloading robot 8 transfers the SiC wafer to the loading chamber 7.

[0140] The existing SiC wafer annealing treatment generally requires heating the SiC wafer to 1600-2000°C, while the melting point of Si is about 1400°C. A coating needs to be performed on the surface of the SiC wafer to prevent Si from volatilizing during the annealing treatment. Above 1600°C, the protective layer material begins to become unstable, and the protective effect on Si is limited. The method of the embodiment of the present application combines microwave heating and electron gun heating to change the temperature required for the annealing treatment of the SiC wafer to around 1100°C, which is lower than the melting point of Si and will not cause the protective layer material to become unstable. Then, the SiC wafer is heated by an electron gun at a heating temperature of 1200°C to achieve efficient, high-quality and stable annealing treatment.

[0141] In summary, the embodiments of the present application provide a semiconductor annealing method, an annealing device and an annealing system, wherein the annealing method combines microwave heating and electron beam heating to anneal SiC semiconductor sheets. The SiC semiconductor sheet is heated to a first temperature threshold by microwave heating, and the temperature required for annealing the SiC semiconductor sheet can be reduced to below the melting point of single crystal silicon. Electron beam heating with a heating temperature lower than the melting point of single crystal silicon is then used to perform precise temperature-controlled annealing on the SiC semiconductor sheet. This can reduce the annealing temperature and improve the annealing efficiency while ensuring the annealing effect, and solve the problem of damage to the surface elements or protective layer of the SiC semiconductor sheet.

[0142] In the embodiments provided in this application, it should be understood that the disclosed devices and methods can be implemented in other ways.

[0143] In addition, the units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0144] Furthermore, the functional modules in the various embodiments of the present application may be integrated together to form an independent part, or each module may exist separately, or two or more modules may be integrated to form an independent part.

[0145] In this document, relational terms such as first and second, etc. are used merely to distinguish one entity or operation from another entity or operation, but do not necessarily require or imply any such actual relationship or order between these entities or operations.

[0146] The above description is only an embodiment of the present application and is not intended to limit the protection scope of the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A semiconductor annealing method for annealing a SiC semiconductor sheet, characterized in that: The method comprises the following steps: Acquiring surface temperature information of the SiC semiconductor sheet; Performing microwave heating on the SiC semiconductor sheet; When the surface temperature information reaches a preset first temperature threshold, the SiC semiconductor sheet is subjected to mobile electron beam heating at a heating temperature lower than the melting point of single crystal silicon until the annealing treatment of the SiC semiconductor sheet is completed, and the first temperature threshold is 400-600° C.; The step of performing mobile electron beam heating on the SiC semiconductor sheet at a heating temperature lower than the melting point of single crystal silicon until the annealing treatment of the SiC semiconductor sheet is completed comprises: locally heating the SiC semiconductor sheet using an electron beam; When the surface temperature information reaches a preset second temperature threshold, the local heating position of the electron beam is switched according to a preset annealing path. The second temperature threshold is less than the melting point temperature of the single crystal silicon, and the second temperature threshold is 1.5-3 times the first temperature threshold.

2. A semiconductor annealing device, characterized in that: Used to anneal SiC semiconductor sheets using the semiconductor annealing method according to claim 1, the semiconductor annealing device comprising: Annealing chamber (1); A supporting mechanism (2), fixed in the annealing chamber (1) and used for supporting the SiC semiconductor sheet; A temperature measuring mechanism (3), arranged above the supporting mechanism (2), and used for measuring surface temperature information of the SiC semiconductor sheet; A microwave heating mechanism (4) is arranged below the supporting mechanism (2) and is used to perform microwave heating on the SiC semiconductor sheet; An electron beam heating mechanism (5) is arranged above the supporting mechanism (2) and is used to locally heat the surface of the SiC semiconductor sheet using an electron beam; A moving mechanism (6) is used to switch the local heating position of the electron beam heating mechanism (5) on the surface of the SiC semiconductor sheet to achieve mobile electron beam heating.

3. The semiconductor annealing device according to claim 2, characterized in that: The moving mechanism (6) comprises: A first rotating assembly (61) is mounted on the supporting mechanism (2) and is used to drive the SiC semiconductor sheet to rotate; A first linear drive component (62) is connected to the electron beam heating mechanism (5) and is used to drive the electron beam heating mechanism (5) to perform horizontal displacement.

4. The semiconductor annealing device according to claim 2, characterized in that: The moving mechanism (6) comprises: A longitudinal driving component (63) connected to the electron beam heating mechanism (5) and used to drive the electron beam heating mechanism (5) to perform longitudinal horizontal displacement; A transverse driving component (64) is connected to the longitudinal driving component (63) and is used to drive the electron beam heating mechanism (5) to perform transverse horizontal displacement.

5. The semiconductor annealing device according to claim 2, characterized in that: The moving mechanism (6) comprises: A second rotating assembly (65) is mounted on the supporting mechanism (2) and is used to drive the SiC semiconductor sheet to rotate; The second linear drive assembly (66) is connected to the second rotating assembly (65) and is used to drive the second rotating assembly (65) to perform horizontal displacement.

6. The semiconductor annealing device according to claim 2, characterized in that: The temperature measuring position of the temperature measuring mechanism (3) is aligned with the local heating position of the electron beam heating mechanism (5).

7. The semiconductor annealing device according to claim 2, characterized in that: The semiconductor annealing device also includes a loading chamber (7) for storing the SiC semiconductor sheet and a loading and unloading robot (8) for transferring the SiC semiconductor sheet.

8. A semiconductor annealing system for annealing SiC semiconductor sheets, characterized in that: The semiconductor annealing system comprises a semiconductor annealing device and a controller (9), wherein the semiconductor annealing device comprises: Annealing chamber (1); A supporting mechanism (2), fixed in the annealing chamber (1) and used for supporting the SiC semiconductor sheet; A temperature measuring mechanism (3), arranged above the supporting mechanism (2), and used for measuring surface temperature information of the SiC semiconductor sheet; A microwave heating mechanism (4) is arranged below the supporting mechanism (2) and is used to perform microwave heating on the SiC semiconductor sheet; An electron beam heating mechanism (5) is arranged above the supporting mechanism (2) and is used to locally heat the surface of the SiC semiconductor sheet using an electron beam; A moving mechanism (6) for switching the local heating position of the electron beam heating mechanism (5) on the surface of the SiC semiconductor sheet to achieve mobile electron beam heating; The controller (9) is electrically connected to the temperature measuring mechanism (3), the microwave heating mechanism (4), the electron beam heating mechanism (5) and the moving mechanism (6); The controller (9) is used to obtain the surface temperature information; The controller (9) is also used to control the microwave heating mechanism (4) to perform microwave heating on the SiC semiconductor sheet; The controller (9) is further used to control the electron beam heating mechanism (5) and the moving mechanism (6) to cooperate with each other to perform mobile electron beam heating on the SiC semiconductor sheet using a heating temperature lower than the melting point of single crystal silicon, until the annealing treatment of the SiC semiconductor sheet is completed, when the surface temperature information reaches a preset first temperature threshold, the first temperature threshold being 400-600° C.; The step of performing mobile electron beam heating on the SiC semiconductor sheet at a heating temperature lower than the melting point of single crystal silicon until the annealing treatment of the SiC semiconductor sheet is completed comprises: locally heating the SiC semiconductor sheet using an electron beam; When the surface temperature information reaches a preset second temperature threshold, the local heating position of the electron beam is switched according to a preset annealing path. The second temperature threshold is less than the melting point temperature of the single crystal silicon, and the second temperature threshold is 1.5-3 times the first temperature threshold.

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