Method and apparatus for laser annealing of an electrode

Abstract

Embodiments of the present application disclose a laser annealing method and device for an electrode. The method comprises: providing a substrate; wherein the substrate comprises a first electrode setting area; forming a first doped layer on one side of the substrate; wherein the first doped layer is doped with a first doping source; forming a first metal layer on the side of the first doped layer away from the substrate; using a first laser to heat treat the first doped layer and the first metal layer located in the first electrode setting area, so that the first doping source and metal molecules in the first metal layer diffuse to the first electrode setting area; and using a second laser to heat treat the first metal layer located in the first electrode setting area, so that the first metal layer forms an ohmic contact with the substrate. The technical scheme provided by the embodiments of the present application can form a stable and uniform ohmic contact between the first metal layer and the substrate, thereby improving the electrical connection quality of the semiconductor device and the external device.

Description

TECHNICAL FIELD

[0001] Embodiments of the present application relate to the technical field of semiconductor technology, and particularly relate to a laser annealing method and device for an electrode. BACKGROUND

[0002] With the development of semiconductor technology, the performance of semiconductor devices is greatly improved, and the application field of semiconductor devices is also more and more extensive.

[0003] An important structure in a semiconductor device is an electrode, which is used for signal transmission with external devices, and the performance of the electrode directly affects the effective signal transmission between the semiconductor device and the external device. In the prior art, the electrode is formed by depositing metal on the back of the substrate, but the ohmic contact performance of the metal electrode and the non-metal substrate is poor, resulting in low electrical connection quality between the semiconductor device and the external device. SUMMARY

[0004] The present application provides a laser annealing method and device for an electrode to form a stable and uniform ohmic contact between a first metal layer and a substrate, thereby improving the electrical connection quality between the semiconductor device and the external device, and reducing the diffusion control difficulty of the first doping source, simplifying the process steps, and reducing the cost.

[0005] In a first aspect, an embodiment of the present application provides a laser annealing method for an electrode, which comprises:

[0006] providing a substrate; wherein the substrate comprises a first electrode setting area;

[0007] forming a first doping layer on one side of the substrate; wherein the first doping layer is doped with a first doping source;

[0008] forming a first metal layer on the side of the first doping layer away from the substrate;

[0009] using a first laser to heat treat the first doping layer and the first metal layer located in the first electrode setting area, so that the first doping source and metal molecules in the first metal layer diffuse to the first electrode setting area;

[0010] using a second laser to heat treat the first metal layer located in the first electrode setting area, so that the first metal layer forms an ohmic contact with the substrate.

[0011] Optionally, the forming of the first doping layer on one side of the substrate comprises:

[0012] depositing the first doping layer on one side of the substrate;

[0013] the forming of the first metal layer on the side of the first doping layer away from the substrate comprises:

[0014] forming the first metal layer on a side of the first doped layer away from the substrate.

[0015] Optionally, the method further comprises:

[0016] removing portions of the first doped layer and the first metal layer outside the first electrode setting area.

[0017] Optionally, the forming the first doped layer on a side of the substrate comprises:

[0018] the forming the first doped layer on a side of the substrate by evaporation through a mask plate;

[0019] the forming the first metal layer on a side of the first doped layer away from the substrate comprises:

[0020] the forming the first metal layer on a side of the first doped layer away from the substrate by evaporation through a mask plate;

[0021] wherein the orthographic projection of the first doped layer on the substrate and the orthographic projection of the first metal layer on the substrate both coincide with the first electrode setting area.

[0022] Optionally, the substrate further comprises a second electrode setting area; the method further comprises:

[0023] forming a second doped layer on a side of the substrate; wherein the second doped layer contains a second doping source; one of the first doping source and the second doping source comprises a P-type doping source, and the other comprises an N-type doping source; the first doped layer and the second doped layer are on the same side of the substrate;

[0024] forming a second metal layer on a side of the second doped layer away from the substrate;

[0025] using the first laser to perform heat treatment on the second doped layer and the second metal layer located in the second electrode setting area, so that the second doping source and metal molecules in the second metal layer diffuse to the second electrode setting area;

[0026] using the second laser to perform heat treatment on the second metal layer located in the second electrode setting area, so that the second metal layer forms ohmic contact with the substrate.

[0027] Optionally, the P-type doping source comprises boron and its compounds or gallium and its compounds; and the N-type doping source comprises phosphorus and its compounds.

[0028] Optionally, the material of the first metal layer and the second metal layer comprises titanium, nickel, aluminum or cobalt.

[0029] Optionally, the material of the substrate comprises silicon carbide, and the main body material of the first doped layer and the second doped layer comprises silicon carbide or silicon oxide.

[0030] Optionally, the wavelength range of the laser output by the first laser comprises 500nm-1100nm, and the pulse width range comprises 20ns-500ns; the wavelength range of the laser output by the second laser comprises 150nm-400nm, and the pulse width range comprises 1ns-20ns.

[0031] In a second aspect, the embodiment of the present application further provides a laser annealing device for electrode, which comprises:

[0032] a light source system, which comprises a first laser and a second laser;

[0033] a light path transmission system, which is used for transmitting the laser output by the first laser and the second laser to a first electrode setting area of a substrate;

[0034] a detection system, which is used for detecting the ohmic contact performance of the substrate and the first metal layer.

[0035] The laser annealing method for electrode provided by the embodiment of the present application can increase the carrier concentration of the first electrode setting area of the substrate by forming the first doped layer containing the first doping source before forming the first metal layer on the back of the substrate, and then using the first laser to heat treat the first doped layer and the first metal layer located in the first electrode setting area, so that the first doping source and the metal molecules in the first metal layer diffuse to the first electrode setting area. In this way, the contact resistance of the substrate and the first metal layer can be reduced. Moreover, the second laser is used to heat treat the first metal layer located in the first electrode setting area, so that the first metal layer can be melted and uniformly distributed in the first electrode setting area, which is beneficial to improving the stability of the ohmic contact of the substrate and the first metal layer and the uniformity of the contact resistance. The problem of poor ohmic contact performance of the substrate and the electrode is solved, and the effects of improving the stability of the ohmic contact of the substrate and the first metal layer, improving the uniformity of the contact resistance, and reducing the size of the contact resistance are achieved. BRIEF DESCRIPTION OF DRAWINGS

[0036] Figure 1 is a flow chart of a laser annealing method for electrode provided by the embodiment of the present application;

[0037] Figure 2 is a structural schematic diagram of a substrate provided by the embodiment of the present application;

[0038] Figure 3 is a structural schematic diagram of a substrate after a first doped layer is deposited on one side of the substrate provided by the embodiment of the present application;

[0039] Figure 4 is Figure 3 a sectional view along AA' direction;

[0040] Figure 5 is a structural schematic diagram provided by an embodiment of the present application after a first metal layer is deposited on the side of the first doped layer away from the substrate;

[0041] Figure 6 is Figure 5 a sectional view along BB' direction;

[0042] Figure 7 is a structural schematic diagram provided by an embodiment of the present application after the first doped layer and the first metal layer are removed from the part outside the first electrode setting area;

[0043] Figure 8 is Figure 7 a structural schematic diagram along CC' direction in the middle;

[0044] Figure 9 is a flow chart of another laser annealing method of an electrode provided by an embodiment of the present application;

[0045] Figure 10 is a structural schematic diagram of another substrate provided by an embodiment of the present application;

[0046] Figure 11 is a structural schematic diagram provided by an embodiment of the present application after a first doped layer is formed by evaporation through a mask plate;

[0047] Figure 12 is Figure 11 a sectional view along DD' direction in the middle;

[0048] Figure 13 is a structural schematic diagram provided by an embodiment of the present application after a first metal layer is formed by evaporation through a mask plate;

[0049] Figure 14 is Figure 13 a sectional view along EE' direction in the middle;

[0050] Figure 15 is a structural schematic diagram provided by an embodiment of the present application after a second doped layer is formed by evaporation through a mask plate;

[0051] Figure 16 is Figure 15 a sectional view along FF' direction in the middle;

[0052] Figure 17 is a structural schematic diagram provided by an embodiment of the present application after a second metal layer is formed by evaporation through a mask plate;

[0053] Figure 18is Figure 17 a cross-sectional view along the direction of GG';

[0054] Figure 19 is a structural schematic diagram of a laser annealing device of an electrode provided by an embodiment of the present application. DETAILED DESCRIPTION

[0055] The present application will be further described below in conjunction with the drawings and embodiments. It should be understood that the specific embodiments described herein are merely intended for the purpose of interpretation of the present application and are not limiting of the present application. In addition, it should be noted that only the parts related to the present application are shown in the drawings for the purpose of description.

[0056] In view of the problems mentioned in the background art, an embodiment of the present application provides a laser annealing method of an electrode, which comprises the following steps:

[0057] providing a substrate; wherein the substrate comprises a first electrode setting area;

[0058] forming a first doped layer on one side of the substrate; wherein the first doped layer is doped with a first doping source;

[0059] forming a first metal layer on the side of the first doped layer away from the substrate;

[0060] using a first laser to perform heat treatment on the first doped layer and the first metal layer located in the first electrode setting area, so that the first doping source and metal molecules in the first metal layer diffuse to the first electrode setting area;

[0061] using a second laser to perform heat treatment on the first metal layer located in the first electrode setting area, so that the first metal layer forms an ohmic contact with the substrate.

[0062] The above is the core idea of the present application. The technical solutions in the embodiments of the present application will be described clearly and completely in conjunction with the drawings of the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0063] Figure 1 is a flowchart of a laser annealing method of an electrode provided by an embodiment of the present application. Referring to Figure 1 , the method comprises the following steps:

[0064] S110, providing a substrate.

[0065] Specifically, the material of the substrate can be set by those skilled in the art according to actual conditions, which is not limited herein. Optionally, the material of the substrate comprises silicon carbide.

[0066] Exemplarily, Figure 2 is a structural schematic diagram of a substrate provided by an embodiment of the present application. Referring to Figure 2 The substrate 10 comprises a first electrode arrangement area 11, and the first electrode arrangement area 11 comprises a plurality of first electrode sub-arrangement areas 111, each of which corresponds to an electrode. Figure 2 The first electrode arrangement area 11 is exemplarily shown as comprising six first electrode sub-arrangement areas 111 in the figure, but this is not a limitation on the embodiments of the present application, and the number of the first electrode sub-arrangement areas 111 can be set according to actual conditions by those skilled in the art.

[0067] S120, forming a first doped layer on one side of the substrate.

[0068] Specifically, the thickness of the first doped layer can be set by those skilled in the art according to actual conditions, which is not limited here. Exemplarily, the thickness of the first doped layer ranges from 10 nm to 500 nm. Specifically, the first doped layer comprises a host material and a first doping source, and the specific materials of the host material and the first doping source can be set by those skilled in the art according to actual conditions, which is not limited here. Optionally, the host material of the first doped layer comprises silicon carbide or silicon oxide, and preferably, the host material of the first doped layer comprises silicon carbide. It can be understood that when the material of the substrate 10 and the host material of the first doped layer are both silicon carbide, the materials of the two are the same, so that when the first doped layer is formed on one side of the substrate 10, the contact surface between the first doped layer and the substrate 10 is not prone to defects. Optionally, the first doping source comprises a P-type doping source or an N-type doping source, and the type of the doping source and the doping concentration can be selected by those skilled in the art according to actual conditions, which is not limited here.

[0069] Optionally, S120 can specifically comprise: depositing to form the first doped layer on one side of the substrate.

[0070] Exemplarily, Figure 3 is a structural schematic diagram of the substrate after the first doped layer is deposited on one side of the substrate provided by an embodiment of the present application. Figure 4 is Figure 3 is a sectional view along the direction of AA'. Referring to Figure 3 and Figure 4 The silicon carbide material is deposited on the whole surface of one side of the substrate 10 to form the first doped layer 20. The specific deposition manner of the first doped layer 20 can be set by those skilled in the art according to actual conditions, which is not limited here. Exemplarily, the first doped layer 20 can be deposited by physical vapor deposition or chemical vapor deposition.

[0071] S130, forming a first metal layer on the side of the first doped layer away from the substrate.

[0072] Specifically, the material and thickness of the first metal layer can be set by those skilled in the art according to actual conditions, which are not limited herein. For example, the material of the first metal layer can be titanium, nickel, aluminum, cobalt or other metal materials known by those skilled in the art. The thickness of the first metal layer ranges from 10 nm to 400 nm.

[0073] Optionally, S130 can specifically include: depositing a first metal layer on the side of the first doped layer away from the substrate.

[0074] For example, Figure 5 is a structural schematic diagram of the present application after a first metal layer is deposited on the side of the first doped layer away from the substrate. Figure 6 is Figure 5 is a sectional view along the direction of BB'. Referring to Figure 5 and Figure 6 A metal material is deposited on the side of the first doped layer 20 away from the substrate 10 to form a first metal layer 30. The specific deposition method of the first metal layer 30 can be set by those skilled in the art according to actual conditions, which is not limited herein. For example, the first metal layer 30 can be deposited by physical vapor deposition or chemical vapor deposition.

[0075] It can be understood that by depositing the first doped layer 20 and the first metal layer 30, the first doped layer material and the first metal layer material can be deposited without distinction in different regions of the substrate 10, which can reduce the preparation difficulty of the first doped layer 20 and the first metal layer 30.

[0076] S140, using a first laser to heat treat the first doped layer and the first metal layer located in the first electrode setting area, so that the metal molecules in the first doped source and the first metal layer diffuse to the first electrode setting area.

[0077] Specifically, the wavelength and pulse width of the laser output by the first laser can be selected by those skilled in the art according to the materials of the first doped layer 20 and the first metal layer 30, which are not limited herein, as long as the effect of diffusing the metal molecules in the first doped source and the first metal layer 30 to the first electrode setting area 11 can be achieved. For example, the wavelength of the laser output by the first laser ranges from 500 nm to 1100 nm, and the pulse width ranges from 20 ns to 500 ns. When the main material of the first doped layer 20 is silicon carbide or silicon oxide, and the material of the first metal layer 30 includes titanium, nickel, aluminum or cobalt, if the wavelength and pulse width of the laser output by the first laser are in the above range, the metal molecules in the first doped source and the first metal layer 30 can be effectively diffused to the first electrode setting area 11.

[0078] Specifically, the laser output by the first laser is irradiated on the first metal layer 30, and each position of the first electrode setting area 11 is heat-treated by fine-tuning the spot position of the laser. It can be understood that the first doping source is diffused to the substrate 10 by the heat treatment, which can improve the carrier concentration of the first electrode setting area 11 of the substrate 10. When the prepared semiconductor device works, the contact resistance between the substrate 10 and the first metal layer 30 in the first electrode setting area 11 can be reduced due to the high carrier concentration of the first electrode setting area 11. In addition, the metal molecules in the first metal layer 30 are diffused to the substrate 10 by the heat treatment, which can complete the ohmic contact between the substrate 10 and the first metal layer 30 in the first electrode setting area 11. In addition, since the first laser is not used to heat treat the area outside the first electrode setting area 11, the carrier concentration of the area outside the first electrode setting area 11 in the substrate 10 is relatively low, and the problem of leakage current will not occur.

[0079] It can also be understood that if the doping of the first doping source is performed first and then the doping of the metal molecules in the first metal layer 30 is performed, two doping processes are required, and the subsequent metal molecule doping process will affect the doping of the first doping source which has been doped, resulting in complex process steps and difficulty in controlling the diffusion of the first doping source. However, in the embodiment of the present application, the first doping source and the metal molecules in the first metal layer are diffused to the first electrode setting area by one heat treatment process, which can simplify the process steps and reduce the cost. In addition, the difficulty of controlling the diffusion of the first doping source can also be reduced.

[0080] S150, heat-treating the first metal layer located in the first electrode setting area by using a second laser to form ohmic contact between the first metal layer and the substrate.

[0081] Specifically, the laser output by the first laser is irradiated on the first metal layer 30, and each position of the first electrode setting area 11 is heat-treated by fine-tuning the spot position of the laser. It can be understood that the first doping source is diffused to the substrate 10 by the heat treatment, which can improve the carrier concentration of the first electrode setting area 11 of the substrate 10. When the prepared semiconductor device works, the contact resistance between the substrate 10 and the first metal layer 30 in the first electrode setting area 11 can be reduced due to the high carrier concentration of the first electrode setting area 11. In addition, the metal molecules in the first metal layer 30 are diffused to the substrate 10 by the heat treatment, which can complete the ohmic contact between the substrate 10 and the first metal layer 30 in the first electrode setting area 11. In addition, since the first laser is not used to heat treat the area outside the first electrode setting area 11, the carrier concentration of the area outside the first electrode setting area 11 in the substrate 10 is relatively low, and the problem of leakage current will not occur.

[0082] Specifically, the wavelength and pulse width of the laser output by the second laser can be selected by those skilled in the art according to the material of the first metal layer 30, which is not limited herein, as long as the first metal layer 30 can be melted. For example, the wavelength of the laser output by the second laser ranges from 150 nm to 400 nm, and the pulse width ranges from 1 ns to 20 ns. When the material of the first metal layer 30 includes titanium, nickel, aluminum or cobalt, if the wavelength and pulse width of the laser output by the second laser are within the above ranges, the first metal layer 30 can be quickly and sufficiently melted to be laid flat on the first electrode setting area 11, and the first metal layer 30 can be uniformly laid on the first electrode setting area 11 after solidification, which is conducive to improving the contact stability between the substrate 10 and the first metal layer 30 in the first electrode setting area 11.

[0083] Optionally, when the first doped layer 20 and the first metal layer 30 are formed by deposition, the method further comprises, before or after S150, removing the portions of the first doped layer 20 and the first metal layer 30 outside the first electrode setting area 11.

[0084] For example, Figure 7 is a structural schematic diagram of the first doped layer and the first metal layer after the portions outside the first electrode setting area are removed. Figure 8 is Figure 7 is a structural schematic diagram along the direction of CC' in Figure 7 and Figure 8 The first metal layer 30 includes a plurality of discrete first metal blocks 31, and the first doped layer 20 includes a plurality of discrete first doped blocks 21. The first metal block 31 in each first electrode sub-setting area 111 and the first doped block 21 in the same first electrode sub-setting area 111 and the substrate 10 are in ohmic contact, forming an electrode. The specific way of removing the portions of the first doped layer 20 and the first metal layer 30 outside the first electrode setting area 11 can be set by those skilled in the art according to actual conditions, which is not limited herein. For example, the first metal layer 30 can be removed by pickling, alkaline cleaning, etching, etc., and the first doped layer 20 can be removed by etching, etc.

[0085] The laser annealing method for electrodes provided in this invention involves forming a first doped layer containing a first dopant source before forming a first metal layer on the back side of the substrate. Then, a first laser is used to heat-treat the first doped layer and the first metal layer located in the first electrode placement region, causing metal molecules from the first dopant source and the first metal layer to diffuse into the first electrode placement region. This increases the carrier concentration in the first electrode placement region of the substrate, which helps reduce the contact resistance between the substrate and the first metal layer. Furthermore, a second laser is used to heat-treat the first metal layer located in the first electrode placement region, allowing the first metal layer to melt and distribute uniformly in the first electrode placement region, which helps improve the stability of the ohmic contact between the substrate and the first metal layer, as well as the uniformity of the contact resistance. This solves the problem of poor ohmic contact performance between the substrate and the electrode, achieving the effects of improving the stability of the ohmic contact between the substrate and the first metal layer, improving the uniformity of the contact resistance, and reducing the magnitude of the contact resistance.

[0086] Figure 9 This is a flowchart of another laser annealing method for an electrode provided in an embodiment of the present invention. See also... Figure 9 The method includes:

[0087] S210, provides a substrate.

[0088] For example, Figure 10 This is a schematic diagram of another substrate structure provided in an embodiment of the present invention. See also... Figure 10 The substrate 10 includes a first electrode setting region 11 and a second electrode setting region 12. Figure 10 Different line types are used to indicate the first electrode setting area 11 and the second electrode setting area 12, and they do not overlap. The first electrode setting area 11 includes multiple first electrode sub-setting areas 111, each corresponding to one electrode. The second electrode setting area 12 includes multiple second electrode sub-setting areas 121, each corresponding to one electrode. It should be noted that... Figure 10 The illustration only shows that the first electrode setting area 11 includes six first electrode sub-setting areas 111 and the second electrode setting area 12 includes two second electrode sub-setting areas 121, but this is not a limitation on the embodiment of the present invention. Those skilled in the art can set the number of first electrode sub-setting areas 111 and second electrode sub-setting areas 121 according to the actual situation.

[0089] S220, A first doped layer is formed on one side of the substrate.

[0090] S230, a first metal layer is formed on the side of the first doped layer away from the substrate.

[0091] Specifically, the first doped layer and the first metal layer are formed by way of full-area deposition, but are not limited thereto, and the first doped layer and the first metal layer are formed by way of mask evaporation in the following detailed description.

[0092] Optionally, S220 specifically can include forming the first doped layer by mask evaporation on one side of the substrate, and S230 specifically can include forming the first metal layer by mask evaporation on the side of the first doped layer away from the substrate.

[0093] Exemplarily, Figure 11 is a structural schematic diagram of the first doped layer formed by mask evaporation according to an embodiment of the present application. Figure 12 is Figure 11 is a sectional view along the direction of DD' in FIG. Figure 13 is a structural schematic diagram of the first metal layer formed by mask evaporation according to an embodiment of the present application. Figure 14 is Figure 13 is a sectional view along the direction of EE' in FIG. Figures 11-14 The orthogonal projection of the first doped layer 20 on the substrate 10 and the orthogonal projection of the first metal layer 30 on the substrate 10 both coincide with the first electrode setting area 11.

[0094] It can be understood that the first doped layer 20 and the first metal layer 30 are formed by mask evaporation, the area outside the first electrode setting area 11 in the substrate 10 is not covered by the first doped layer 20 material and the first metal layer 30 material, and a process step is not required to remove the first doped layer material and the first metal layer material outside the first electrode setting area 11, so that the process is simple and the cost is reduced.

[0095] S240, using a first laser to perform heat treatment on the first doped layer and the first metal layer located in the first electrode setting area, so that the first doped source and the metal molecules in the first metal layer diffuse to the first electrode setting area.

[0096] S250, forming a second doped layer on one side of the substrate.

[0097] Specifically, the thickness of the second doped layer can be set by those skilled in the art according to actual conditions, which is not limited herein. Exemplarily, the thickness of the second doped layer ranges from 10 nm to 500 nm. Specifically, the second doped layer includes a main body material and a second doped source, and the specific materials of the main body material and the second doped source can be set by those skilled in the art according to actual conditions, which is not limited herein. Optionally, the main body material of the second doped layer includes silicon carbide or silicon oxide, and preferably, the main body material of the second doped layer includes silicon carbide.

[0098] The first doped layer 20 and the second doped layer are located on the same side of the substrate 10. The second doped layer contains a second doped source; one of the first doped source and the second doped source includes a P-type doped source, and the other includes an N-type doped source, so as to form two different types of electrodes subsequently. Specifically, the specific materials of the P-type doped source and the N-type doped source can be set by those skilled in the art according to actual conditions, which are not limited herein. Exemplarily, the P-type doped source includes boron and its compounds or gallium and its compounds; and the N-type doped source includes phosphorus and its compounds.

[0099] It can also be understood that, when the first doped layer 20 and the first metal layer 30 are formed by deposition, before S250, there is further included: removing the portions of the first doped layer 20 and the first metal layer 30 located outside the first electrode setting area 11. In this way, the first doped source can be prevented from diffusing to the second electrode setting area 12.

[0100] S260, forming a second metal layer on the side of the second doped layer away from the substrate.

[0101] Specifically, the material and thickness of the second metal layer can be set by those skilled in the art according to actual conditions, which are not limited herein. Exemplarily, the material of the second metal layer includes titanium, nickel, aluminum or cobalt, and the thickness of the second metal layer ranges from 10 nm to 400 nm. It should be noted that the materials of the first metal layer 30 and the second metal layer can be the same or different, which are not limited herein.

[0102] Optionally, the second doped layer and the second metal layer can be formed by full-area deposition. Specifically, S250 can include: depositing the second doped layer on one side of the substrate, and S260 can include: depositing the second metal layer on the side of the second doped layer away from the substrate. In this way, the second doped layer material and the second metal layer material can be deposited without distinction for different areas of the substrate 10, which can reduce the preparation difficulty of the second doped layer and the second metal layer, and is beneficial to mass production.

[0103] Optionally, the second doped layer and the second metal layer can also be formed by mask evaporation. Specifically, S250 can include: forming the second doped layer on one side of the substrate by mask evaporation, and S260 can include: forming the second metal layer on the side of the second doped layer away from the substrate by mask evaporation. In this way, the process can be simple, and the cost can be reduced. Exemplarily, Figure 15 is a structure schematic diagram after the second doped layer is formed by mask evaporation according to an embodiment of the present application. Figure 16 is a structure schematic diagram after the second doped layer is formed by mask evaporation according to an embodiment of the present application. Figure 15 is a sectional view along the FF' direction in Figure 17 is a structure schematic diagram after the second metal layer is formed by mask evaporation according to an embodiment of the present application. Figure 18 is a structure schematic diagram after the second metal layer is formed by mask evaporation according to an embodiment of the present application.Figure 17 FIG. 4 is a sectional view along the direction of GG'. Figures 15-18 The second doped layer 40 and the second metal layer 50 are formed in the second electrode setting area 12. The second doped layer 40 includes a plurality of discrete second doped blocks 41, and the second metal layer 50 includes a plurality of discrete second metal blocks 51. Each of the second metal blocks 51 in the second electrode sub-setting area 121 and the second doped block 41 in the same second electrode sub-setting area 121 and the substrate 10 form an electrode after ohmic contact.

[0104] S270, heat treating the second doped layer and the second metal layer in the second electrode setting area by using the first laser to diffuse the second doped source and the metal molecules in the second metal layer to the second electrode setting area.

[0105] Specifically, the specific implementation of heat treating the second doped layer 40 and the second metal layer 50 in the second electrode setting area 12 by using the first laser is similar to that of heat treating the first doped layer 20 and the first metal layer 30 in the first electrode setting area 11 by using the first laser, which will not be repeated here.

[0106] It can be understood that, when the second doped layer 40 and the second metal layer 50 are formed by deposition, before S270, it further includes: removing the part of the second doped layer 40 and the second metal layer 50 outside the second electrode setting area 12. In this way, the second doped source can be prevented from diffusing to the first electrode setting area 11. Specifically, the specific implementation of removing the part of the second doped layer 40 and the second metal layer 50 outside the second electrode setting area 12 can be set by those skilled in the art according to the actual situation, which will not be limited here. For example, the removal of the second metal layer 50 can be performed by acid washing, alkali washing, etching, etc., and the removal of the second doped layer 40 can be performed by etching, etc.

[0107] S280, heat treating the first metal layer in the first electrode setting area by using the second laser to form ohmic contact between the first metal layer and the substrate.

[0108] S290, heat treating the second metal layer in the second electrode setting area by using the second laser to form ohmic contact between the second metal layer and the substrate.

[0109] Specifically, the specific implementation of using the second laser to perform heat treatment on the second metal layer 50 located in the second electrode setting area 12 is similar to the specific implementation of using the second laser to perform heat treatment on the first metal layer 30 located in the first electrode setting area 11, and details are not repeated here. It should be noted that the potential barrier of the P-type device is different from that of the N-type device, so the parameters (wavelength, pulse, heat treatment time, etc.) when using the first laser to perform heat treatment on the first electrode setting area and when using the first laser to perform heat treatment on the second electrode setting area are usually different. The person skilled in the art can set it according to the actual situation, and it is not limited here.

[0110] It can be understood that compared to arranging the ohmic contacts of the N-type device and the P-type device on both sides of the substrate, arranging the ohmic contacts of the N-type device and the P-type device on the same side of the substrate does not need to arrange a barrier layer, can simplify the process steps, and reduce the cost.

[0111] The laser annealing method of the electrode provided by the embodiment of the application can diffuse the metal molecules in the first doped source and the first metal layer to the first electrode setting area and diffuse the metal molecules in the second doped source and the second metal layer to the second electrode setting area by using the first laser to perform heat treatment on the first doped layer and the first metal layer located in the first electrode setting area and using the second laser to perform heat treatment on the second doped layer and the second metal layer located in the second electrode setting area. In this way, the ohmic contacts of the N-type device and the P-type device can be formed at the same time, and the process is simple.

[0112] Based on the above-mentioned inventive concept, the embodiment of the application further provides a laser annealing device of an electrode. Figure 19 is a structural schematic diagram of a laser annealing device of an electrode provided by the embodiment of the application. Referring to Figure 19 The laser annealing device of the electrode comprises: a light source system 1, the light source system 1 comprising a first laser and a second laser; a light path transmission system 2 for transmitting the laser output by the first laser and the second laser to a first electrode setting area of a substrate; and a detection system 3 for detecting the ohmic contact performance of the substrate and a first metal layer.

[0113] Optionally, the wavelength range of the laser output by the first laser comprises 500nm-1100nm, and the pulse width range comprises 20ns-500ns; the wavelength range of the laser output by the second laser comprises 150nm-400nm, and the pulse width range comprises 1ns-20ns.

[0114] It can be understood that when the substrate further comprises a second electrode setting area, the light path transmission system 2 is further used for transmitting the laser output by the first laser and the second laser to the second electrode setting area of the substrate, and the detection system 3 is further used for detecting the ohmic contact performance of the substrate and a second metal layer.

[0115] It should be noted that the specific implementation forms of the optical path transmission system 2 and the detection system 3 can be set by those skilled in the art according to actual conditions, and are not limited here.

[0116] The laser annealing device of the electrode provided by the embodiment of the present application, the first laser can perform heat treatment on the first doped layer and the first metal layer located in the first electrode setting area, so that the first doped source and the metal molecules in the first metal layer diffuse to the first electrode setting area, in this way, the carrier concentration of the first electrode setting area of the substrate is increased, which is beneficial to reduce the contact resistance of the substrate and the first metal layer. Moreover, the second laser can perform heat treatment on the first metal layer located in the first electrode setting area, so that the first metal layer can be melted and uniformly distributed in the first electrode setting area, which is beneficial to improve the stability of the ohmic contact of the substrate and the first metal layer and the uniformity of the contact resistance. The problem of poor ohmic contact performance of the substrate and the electrode is solved, and the effects of improving the stability of the ohmic contact of the substrate and the first metal layer, improving the uniformity of the contact resistance, and reducing the size of the contact resistance are achieved.

[0117] It should be noted that the above are only the preferred embodiments of the present application and the applied technical principles. Those skilled in the art will understand that the present application is not limited to the specific embodiments described herein, and those skilled in the art can make various obvious changes, re-adjustments, mutual combinations and substitutions without departing from the scope of the present application. Therefore, although the present application has been described in more detail through the above embodiments, the present application is not limited to the above embodiments, and can include more other equivalent embodiments without departing from the concept of the present application, and the scope of the present application is determined by the scope of the appended claims.

Claims

1. A method of laser annealing of an electrode, characterized by, The method comprises: providing a substrate; wherein the substrate comprises a first electrode setting area; forming a first doped layer on one side of the substrate; wherein the first doped layer is doped with a first dopant source; forming a first metal layer on the side of the first doped layer away from the substrate; using a first laser to heat treat the first doped layer and the first metal layer located in the first electrode setting area, so that the first dopant source and metal molecules in the first metal layer diffuse to the first electrode setting area; using a second laser to heat treat the first metal layer located in the first electrode setting area, so that the first metal layer forms an ohmic contact with the substrate; the substrate further comprises a second electrode setting area; the method further comprises: forming a second doped layer on one side of the substrate; wherein the second doped layer contains a second dopant source; one of the first dopant source and the second dopant source comprises a P-type dopant source, and the other comprises an N-type dopant source; the first doped layer and the second doped layer are located on the same side of the substrate; forming a second metal layer on the side of the second doped layer away from the substrate; using the first laser to heat treat the second doped layer and the second metal layer located in the second electrode setting area, so that the second dopant source and metal molecules in the second metal layer diffuse to the second electrode setting area; using the second laser to heat treat the second metal layer located in the second electrode setting area, so that the second metal layer forms an ohmic contact with the substrate; the wavelength range of the laser output by the first laser comprises 500nm-1100nm, and the pulse width range comprises 20ns-500ns; the wavelength range of the laser output by the second laser comprises 150nm-400nm, and the pulse width range comprises 1ns-20ns, so that the first metal layer is rapidly and sufficiently melted.

2. The laser annealing method of the electrode according to claim 1, wherein the forming of the first doped layer on one side of the substrate comprises: depositing the first doped layer on one side of the substrate; the forming of the first metal layer on the side of the first doped layer away from the substrate comprises: depositing the first metal layer on the side of the first doped layer away from the substrate.

3. The method of laser annealing of an electrode according to claim 2, wherein, further comprising: removing the portions of the first doped layer and the first metal layer located outside the first electrode setting area.

4. The laser annealing method of the electrode according to claim 1, wherein the forming of the first doped layer on one side of the substrate comprises: the forming of the first doped layer on one side of the substrate through a mask evaporation; the forming of the first metal layer on the side of the first doped layer away from the substrate comprises: the forming of the first metal layer on the side of the first doped layer away from the substrate through a mask evaporation; wherein the orthographic projection of the first doped layer on the substrate and the orthographic projection of the first metal layer on the substrate both coincide with the first electrode setting area.

5. The method of laser annealing of an electrode according to claim 1, wherein, The P-type doping source includes boron and its compounds or gallium and its compounds; the N-type doping source includes phosphorus and its compounds.

6. The method of laser annealing of an electrode according to claim 1, wherein, The material of the first metal layer and the second metal layer includes titanium, nickel, aluminum or cobalt.

7. The method of laser annealing of an electrode according to claim 1, wherein The material of the substrate includes silicon carbide, and the main material of the first doping layer and the second doping layer includes silicon carbide or silicon oxide.

8. An apparatus for laser annealing of an electrode, characterized by The laser annealing method suitable for the electrode of any one of claims 1-7, the laser annealing device of the electrode comprises: A light source system, the light source system comprises a first laser and a second laser; An optical path transmission system for transmitting the laser output by the first laser and the second laser to the first electrode setting area of the substrate; A detection system for detecting the ohmic contact performance of the substrate and the first metal layer. A laser annealing method suitable for the electrode of any one of claims 1-7, the laser annealing device of the electrode comprises: A light source system, the light source system comprises a first laser and a second laser; An optical path transmission system for transmitting the laser output by the first laser and the second laser to the first electrode setting area of the substrate; A detection system for detecting the ohmic contact performance of the substrate and the first metal layer.

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