A fast recovery diode and a method for manufacturing the same

Abstract

The present invention relates to the field of semiconductor technology, and specifically discloses a fast recovery diode, which includes: an N-type substrate material layer, an N-type epitaxial layer and a P-type material layer of a first doping concentration, the surface of the P-type material layer of the first doping concentration includes a plurality of P-type material regions of a second doping concentration, the surface of the N-type substrate material layer away from the N-type epitaxial layer forms a first metal layer, the surface of the P-type material layer of the first doping concentration away from the N-type epitaxial layer forms a second metal layer, the doping concentration of the P-type material layer of the first doping concentration is less than the doping concentration of the P-type material region of the second doping concentration, and the doping concentration of the N-type epitaxial layer close to the P-type material layer of the first doping concentration is greater than the doping concentration of the N-type epitaxial layer close to the N-type substrate material layer. The present invention also discloses a method for manufacturing a fast recovery diode. The fast recovery diode provided by the present invention can improve reliability.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor technology, and in particular to a fast recovery diode and a method for manufacturing the fast recovery diode. Background Art

[0002] With the development of power electronics technology, the application of new power electronic devices in various frequency conversion circuits and chopper circuits has put forward higher requirements for the fast diodes connected in parallel with them to play a clamping or buffering role, so as to reduce the power consumption of the diode reverse recovery charge in the power switch device, reduce the high induced voltage attached to the power switch device due to reverse recovery, and improve the service life and reliability of the power switch device. To this end, the diode must have a short reverse recovery time trr, a small reverse recovery current IRM and a softer recovery characteristic.

[0003] In high-voltage current circuits, traditional PIN diodes have good reverse withstand performance, and the forward voltage drop is very low under high on-state current density, showing a low resistance state. However, due to the long minority carrier lifetime, the switching speed of the diode is correspondingly low, especially the reverse recovery characteristics are poor, which is increasingly unable to meet the development and requirements of power switching devices. Therefore, the development of high-frequency, high-voltage, fast and soft recovery high-power diodes has certain practical significance.

[0004] At present, the fast recovery diodes are basically manufactured with ordinary PIN structures, such as Figure 1 As shown, the manufacturing technology is mainly based on minority carrier lifetime control technologies such as heavy metal Au / Pt doping and electron irradiation. However, these technologies have some inevitable defects, such as large reverse bias leakage under high temperature of electron irradiation, high induced voltage generated by reverse recovery due to poor softness, affecting circuit reliability, high temperature performance degradation of heavy metal Pt doping, and negative temperature coefficient is not suitable for parallel circuits. Summary of the invention

[0005] The present invention provides a fast recovery diode and a method for manufacturing the fast recovery diode, which solves the problem of poor reliability of the fast recovery diode in the related art.

[0006] As a first aspect of the present invention, a fast recovery diode is provided, comprising: an N-type substrate material layer, an N-type epitaxial layer and a P-type material layer with a first doping concentration sequentially arranged on the N-type substrate material layer, the surface of the P-type material layer with the first doping concentration comprising a plurality of P-type material regions with a second doping concentration, the surface of the N-type substrate material layer away from the N-type epitaxial layer forms a first metal layer, the surface of the P-type material layer with the first doping concentration away from the N-type epitaxial layer forms a second metal layer,

[0007] The doping concentration of the P-type material layer of the first doping concentration is less than the doping concentration of the P-type material region of the second doping concentration, the doping concentration of the N-type epitaxial layer close to the N-type substrate material layer is less than the doping concentration of the N-type substrate material layer, and the doping concentration of the N-type epitaxial layer close to the P-type material layer of the first doping concentration is greater than the doping concentration of the N-type epitaxial layer close to the N-type substrate material layer.

[0008] Further, the N-type epitaxial layer includes an N-type epitaxial layer with a first doping concentration, an N-type drift region, and an N-type epitaxial layer with a second doping concentration, which are sequentially arranged on the N-type substrate material layer, the doping concentration of the N-type epitaxial layer with the first doping concentration is less than the doping concentration of the N-type substrate material layer, and is greater than the doping concentration of the N-type drift region, and the doping concentration of the N-type drift region is less than the doping concentration of the N-type epitaxial layer with the second doping concentration.

[0009] Furthermore, the surface of the P-type material layer of the first doping concentration includes a plurality of uniformly distributed P-type material regions of the second doping concentration, and the depth of each of the P-type material regions of the second doping concentration is much smaller than the depth of the P-type material layer of the first doping concentration.

[0010] Furthermore, the first metal layer and the second metal layer are both made of aluminum.

[0011] As another aspect of the present invention, a method for manufacturing a fast recovery diode is provided, which is used to manufacture the fast recovery diode mentioned above, wherein the manufacturing method comprises:

[0012] Providing an N-type substrate material layer;

[0013] forming an N-type epitaxial layer on the N-type substrate material layer, wherein the doping concentration of the N-type epitaxial layer close to the N-type substrate material layer is less than the doping concentration of the N-type substrate material layer;

[0014] Implanting a first dose of boron ions on the N-type epitaxial layer to form a P-type material layer with a first doping concentration;

[0015] Implanting a second dose of boron ions on the surface of the P-type material layer of the first doping concentration to form a P-type material region of the second doping concentration, wherein the doping concentration of the P-type material layer of the first doping concentration is less than the doping concentration of the P-type material region of the second doping concentration, and the doping concentration of the N-type epitaxial layer close to the P-type material layer of the first doping concentration is greater than the doping concentration of the N-type epitaxial layer close to the N-type substrate material layer;

[0016] Metal is sputtered respectively on a surface of the P-type material layer with the first doping concentration away from the N-type epitaxial layer and a surface of the N-type substrate material layer away from the N-type epitaxial layer to form a corresponding second metal layer and first metal layer.

[0017] Further, the forming of an N-type epitaxial layer on the N-type substrate material layer comprises:

[0018] Implanting N-type ions on the N-type substrate material layer and performing annealing to form an N-type epitaxial layer with a first doping concentration;

[0019] Implanting N-type ions into the N-type epitaxial layer of the first doping concentration and performing annealing to form an N-type drift region;

[0020] Implanting phosphorus ions into the N-type drift region, and performing annealing to form an N-type epitaxial layer with a second doping concentration;

[0021] Among them, the doping concentration of the N-type epitaxial layer with the first doping concentration is less than the doping concentration of the N-type substrate material layer, and is greater than the doping concentration of the N-type drift region, and the doping concentration of the N-type drift region is less than the doping concentration of the N-type epitaxial layer with the second doping concentration.

[0022] Furthermore, the implantation dose of the phosphorus ions is 1*10 12 Pieces / cm 2 ~5*10 13 Pieces / cm 2 The energy of the phosphorus ions is between 1.5 MeV and 6 MeV.

[0023] Further, the step of implanting a first dose of boron ions into the N-type epitaxial layer to form a P-type material layer with a first doping concentration includes:

[0024] A first dose of boron ions is implanted into the N-type epitaxial layer, and a P-type material layer with a first doping concentration at a first depth is formed after high-temperature annealing, wherein the first dose is 1*10 12 Pieces / cm 2 ~1*10 14 Pieces / cm 2 The first depth is between 3 μm and 10 μm.

[0025] Further, the step of implanting a second dose of boron ions on the surface of the P-type material layer of the first doping concentration to form a P-type material region of the second doping concentration includes:

[0026] A second dose of boron ions is implanted on the surface of the P-type material layer with the first doping concentration, and high temperature activation is performed to obtain a plurality of uniformly distributed P-type material regions with the second doping concentration, wherein the second dose is 1*10 14Pieces / cm 2 ~1*10 15 Pieces / cm 2 The activation temperature of the high temperature activation is between 900° C. and 1000° C., and the time of the high temperature activation is between 30 min and 60 min.

[0027] Furthermore, the depth of each P-type material region of the second doping concentration is much smaller than the first depth.

[0028] The fast recovery diode provided by the present invention adjusts the anode carrier injection efficiency, weakens the conductivity modulation effect, and the minority carrier concentration is linearly distributed from the anode to the cathode, thereby obtaining a faster reverse recovery time, smaller dynamic loss, better softness, smaller high-temperature leakage, higher reliability, and a smaller temperature coefficient. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the present invention but do not constitute a limitation of the present invention. In the accompanying drawings:

[0030] Figure 1 It is a cross-sectional view of a common PIN structure in the prior art.

[0031] Figure 2 This is a schematic structural diagram of the fast recovery diode provided by the present invention.

[0032] Figure 3 The fast recovery diode provided by the present invention and Figure 1 The schematic diagram of the comparison of dynamic test results of the electron irradiation process of the ordinary PIN structure is shown.

[0033] Figure 4 The fast recovery diode provided by the present invention and Figure 1 The diagram below shows a comparison of high temperature leakage of a common PIN structure.

[0034] Figure 5 This is a flow chart of the method for manufacturing the fast recovery diode provided by the present invention. DETAILED DESCRIPTION

[0035] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0036] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiment of the present invention. Obviously, the described embodiment is only a part of the embodiment of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work should fall within the scope of protection of the present invention.

[0037] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so as to describe the embodiments of the present invention described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0038] In this embodiment, a fast recovery diode is provided. Figure 2 is a schematic diagram of the structure of a fast recovery diode provided according to an embodiment of the present invention, such as Figure 2 As shown, it includes: an N-type substrate material layer 10, an N-type epitaxial layer 20 and a P-type material layer 30 with a first doping concentration sequentially arranged on the N-type substrate material layer 10, the surface of the P-type material layer 30 with the first doping concentration includes a plurality of P-type material regions 31 with a second doping concentration, the surface of the N-type substrate material layer 10 away from the N-type epitaxial layer forms a first metal layer (not shown in the figure), and the surface of the P-type material layer 30 with the first doping concentration away from the N-type epitaxial layer forms a second metal layer (not shown in the figure),

[0039] The doping concentration of the P-type material layer 30 of the first doping concentration is less than the doping concentration of the P-type material region 31 of the second doping concentration, the doping concentration of the N-type epitaxial layer 20 close to the N-type substrate material layer 10 is less than the doping concentration of the N-type substrate material layer 10, and the doping concentration of the N-type epitaxial layer 20 close to the P-type material layer 30 of the first doping concentration is greater than the doping concentration of the N-type epitaxial layer 20 close to the N-type substrate material layer 10.

[0040] It should be understood that in the fast recovery diode provided by the embodiment of the present invention, the P-type material layer 30 of the first doping concentration is formed with a plurality of P-type material regions 31 of the second doping concentration thereon, which constitute the anode of the fast recovery diode. Since the doping concentration of the P-type material layer 30 of the first doping concentration is less than the doping concentration of the P-type material region 31 of the second doping concentration, the concentration suddenly changes at the junction of the P-type material layer 30 of the first doping concentration and the P-type material region 31 of the second doping concentration, and a diffusion potential, i.e., a high-low junction diffusion potential, can be generated at the interface. This potential prevents the hole current from drifting to the cathode surface, so that most of the hole current flows away through the P-type material layer 30 of the first doping concentration. The current flowing through the P-type material layer 30 of the first doping concentration generates a lateral voltage drop on the junction at the interface. By adjusting the doping concentration of the P-type material layer 30 with the first doping concentration and the size of the P-type material region 31 with the second doping concentration, it can be ensured that before the diode current density reaches a certain design value, the junction at the interface has only a very small hole injection efficiency. After reaching the design value, the lateral voltage drop is higher than the diffusion potential, resulting in a high hole injection effect, thereby achieving the adjustment of the anode carrier injection efficiency.

[0041] Therefore, the fast recovery diode provided in the embodiment of the present invention adjusts the anode carrier injection efficiency, weakens the conductivity modulation effect, and the minority carrier concentration is linearly distributed from the anode to the cathode, thereby obtaining a faster reverse recovery time, smaller dynamic loss, better softness, smaller high-temperature leakage, higher reliability, and a small temperature coefficient.

[0042] It should be understood that the N-type substrate material layer 10 specifically corresponds to Figure 2 The N+ region in the first doping concentration of the P-type material layer 30 specifically corresponds to Figure 2 The P- region in FIG. 2 , the P-type material region 31 of the second doping concentration specifically corresponds to the P+ region in FIG. 2 .

[0043] In the embodiment of the present invention, Figure 2 As shown, the N-type epitaxial layer 20 includes an N-type epitaxial layer 21 with a first doping concentration, an N-type drift region 22, and an N-type epitaxial layer 23 with a second doping concentration, which are sequentially arranged on the N-type substrate material layer 10. The doping concentration of the N-type epitaxial layer 21 with the first doping concentration is less than the doping concentration of the N-type substrate material layer 10, and is greater than the doping concentration of the N-type drift region 22. The doping concentration of the N-type drift region 22 is less than the doping concentration of the N-type epitaxial layer 23 with the second doping concentration.

[0044] It should be understood that the N-type epitaxial layer 21 of the first doping concentration specifically corresponds to Figure 2 The N-buffer in the embodiment of the present invention, the N-type drift region 22 specifically corresponds to Figure 2N-Drift in the embodiment, the N-type epitaxial layer 23 of the second doping concentration specifically corresponds to Figure 2 N- in.

[0045] In the embodiment of the present invention, the N- corresponding to the N-type epitaxial layer 23 of the second doping concentration is arranged below the P- region corresponding to the P-type material layer 30 of the first doping concentration, and the doping concentration of N- is greater than the doping concentration of N-Drift, which reduces the conductivity modulation effect, greatly reduces the carrier injection efficiency when turned on, improves the carrier distribution when turned on, and reduces the negative impact of using minority carrier lifetime control technology, thereby reducing the reverse recovery time and reducing high-temperature leakage current. Since the doping concentration of N-Buffer is higher than the doping concentration of N-Drift, the expansion of the depletion region after reaching the buffer layer is significantly slowed down during the reverse recovery process. In this way, after the minority carrier storage time, there are still a large number of carriers in the buffer layer that have not been recombined or extracted, so that the recombination time is correspondingly increased, thereby improving the softness factor of the diode.

[0046] It should be understood that after the anode carrier injection control of the embodiment of the present invention, only a very low dose of electron irradiation is required to control the carrier lifetime in the entire region, which can further improve the performance and effectively reduce the reverse leakage current of the fast recovery diode at high temperature.

[0047] like Figure 3 and Figure 4 As shown, they are respectively the fast recovery diode and Figure 1 The following are the schematic diagrams for comparing the dynamic test results of the electron irradiation process of a common PIN structure and the high-temperature leakage current comparison.

[0048] Depend on Figure 3 and Figure 4 It can be seen that the directional recovery IRM of the fast recovery diode provided by the present invention is significantly smaller, and there is no oscillation phenomenon; the high-temperature leakage current of this structure rarely uses the minority carrier lifetime control technology, and the high-temperature reverse leakage current is much lower.

[0049] Specifically, Figure 2 As shown, the surface of the P-type material layer of the first doping concentration includes a plurality of uniformly distributed P-type material regions of the second doping concentration, and the depth of each of the P-type material regions of the second doping concentration is much smaller than the depth of the P-type material layer of the first doping concentration.

[0050] It should be understood that the volume of the P-type material region 31 with the second doping concentration can be adjusted as needed, and the embodiment of the present invention does not limit this.

[0051] It should be noted that the P-type material layer 30 with a first doping concentration and the P-type material region 31 with a second doping concentration provided in the embodiment of the present invention are both formed by boron ion implantation, wherein the concentration of the boron ions implanted in the P-type material region 31 with the second doping concentration is greater than the concentration of the boron ions implanted in the P-type material layer 30 with the first doping concentration.

[0052] In addition, the N-type epitaxial layer 23 of the second doping concentration in the embodiment of the present invention is specifically formed by high-energy phosphorus ion implantation and annealing activation, thereby being able to suppress anode carrier hole injection without affecting the on-state voltage drop VF.

[0053] Preferably, the first metal layer and the second metal layer are both made of aluminum.

[0054] It should be understood that the first metal layer is a cathode metal layer, and the second metal layer is an anode metal layer.

[0055] As another embodiment of the present invention, a method for manufacturing a fast recovery diode is provided, which is used to manufacture the fast recovery diode described above, wherein: Figure 5 As shown, the manufacturing method comprises:

[0056] S110, providing an N-type substrate material layer;

[0057] It should be understood that the specific N-type material substrate is Figure 2 The N+ region shown can be formed by high-dose N-type ion implantation activation.

[0058] It should be noted that the material used to make the N-type material substrate layer may specifically include single crystal silicon. The resistivity and final thinning thickness of the N-type material substrate layer are determined by the reverse withstand voltage requirement, which is not limited here.

[0059] S120, forming an N-type epitaxial layer on the N-type substrate material layer, wherein the doping concentration of the N-type epitaxial layer close to the N-type substrate material layer is less than the doping concentration of the N-type substrate material layer;

[0060] Specifically, it may include:

[0061] Implanting N-type ions on the N-type substrate material layer and performing annealing to form an N-type epitaxial layer with a first doping concentration;

[0062] Implanting N-type ions into the N-type epitaxial layer of the first doping concentration and performing annealing to form an N-type drift region;

[0063] Implanting phosphorus ions into the N-type drift region, and performing annealing to form an N-type epitaxial layer with a second doping concentration;

[0064] Among them, the doping concentration of the N-type epitaxial layer with the first doping concentration is less than the doping concentration of the N-type substrate material layer, and is greater than the doping concentration of the N-type drift region, and the doping concentration of the N-type drift region is less than the doping concentration of the N-type epitaxial layer with the second doping concentration.

[0065] In the embodiment of the present invention, the implantation dose of phosphorus ions is 1*10 12 Pieces / cm 2 ~5*10 13 Pieces / cm 2 The energy of the phosphorus ions is between 1.5 MeV and 6 MeV.

[0066] It should be noted that the growth thickness and resistivity of the N-type epitaxial layer with the first doping concentration and the epitaxial layer with the second doping concentration are determined by the reverse withstand voltage requirement and are not limited here.

[0067] S130, implanting a first dose of boron ions into the N-type epitaxial layer to form a P-type material layer with a first doping concentration;

[0068] Specifically, it may include:

[0069] A first dose of boron ions is implanted into the N-type epitaxial layer, and a P-type material layer with a first doping concentration at a first depth is formed after high-temperature annealing, wherein the first dose is 1*10 12 Pieces / cm 2 ~1*10 14 Pieces / cm 2 The first depth is between 3 μm and 10 μm.

[0070] S140, implanting a second dose of boron ions on the surface of the P-type material layer of the first doping concentration to form a P-type material region of the second doping concentration, wherein the doping concentration of the P-type material layer of the first doping concentration is less than the doping concentration of the P-type material region of the second doping concentration, and the doping concentration of the N-type epitaxial layer close to the P-type material layer of the first doping concentration is greater than the doping concentration of the N-type epitaxial layer close to the N-type substrate material layer;

[0071] Specifically, it may include:

[0072] A second dose of boron ions is implanted on the surface of the P-type material layer with the first doping concentration, and high temperature activation is performed to obtain a plurality of uniformly distributed P-type material regions with the second doping concentration, wherein the second dose is 1*10 14 Pieces / cm 2 ~1*10 15 Pieces / cm 2The activation temperature of the high temperature activation is between 900° C. and 1000° C., and the time of the high temperature activation is between 30 min and 60 min.

[0073] It should be understood that the depth of each P-type material region of the second doping concentration is much smaller than the first depth.

[0074] S150, sputtering metal on a surface of the P-type material layer with the first doping concentration away from the N-type epitaxial layer and a surface of the N-type substrate material layer away from the N-type epitaxial layer, respectively, to form a corresponding second metal layer and first metal layer.

[0075] As mentioned above, the first metal layer and the second metal layer are both made of aluminum.

[0076] In summary, the method for manufacturing a fast recovery diode provided by the embodiment of the present invention controls the area of ​​the anode P+ region on the basis of an ordinary PIN structure so that the anode surface forms a P-containing P+ region structure, and at the same time uses high-energy phosphorus ion implantation to form an N- region with a higher concentration than the drift region (N-drift) below the P-, thereby reducing the anode hole carrier injection efficiency, shortening the reverse recovery time, reducing the reverse recovery current, and improving the reverse recovery softness. The P+ region area and the high-energy phosphorus ion implantation dose can be adjusted according to different needs to obtain different degrees of reverse recovery characteristics improvement, and the avalanche tolerance is less affected. In addition, the method for manufacturing a fast recovery diode provided by the embodiment of the present invention has the advantages of simple process and easy implementation.

[0077] The specific working principle of the method for manufacturing the fast recovery diode provided in the embodiment of the present invention can be referred to the description of the fast recovery diode in the foregoing text, and will not be repeated here.

[0078] It is to be understood that the above embodiments are merely exemplary embodiments used to illustrate the principles of the present invention, but the present invention is not limited thereto. For those of ordinary skill in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. A fast recovery diode, characterized in that: The invention comprises: an N-type substrate material layer, an N-type epitaxial layer and a P-type material layer with a first doping concentration sequentially arranged on the N-type substrate material layer, the surface of the P-type material layer with the first doping concentration comprising a plurality of P-type material regions with a second doping concentration, the surface of the N-type substrate material layer away from the N-type epitaxial layer forms a first metal layer, and the surface of the P-type material layer with the first doping concentration away from the N-type epitaxial layer forms a second metal layer; The doping concentration of the P-type material layer of the first doping concentration is less than the doping concentration of the P-type material region of the second doping concentration, the doping concentration of the N-type epitaxial layer close to the N-type substrate material layer is less than the doping concentration of the N-type substrate material layer, and the doping concentration of the P-type material layer of the N-type epitaxial layer close to the first doping concentration is greater than the doping concentration of the N-type epitaxial layer close to the N-type substrate material layer; The N-type epitaxial layer comprises an N-type epitaxial layer with a first doping concentration, an N-type drift region, and an N-type epitaxial layer with a second doping concentration, which are sequentially arranged on the N-type substrate material layer, wherein the doping concentration of the N-type epitaxial layer with the first doping concentration is less than the doping concentration of the N-type substrate material layer and greater than the doping concentration of the N-type drift region, and the doping concentration of the N-type drift region is less than the doping concentration of the N-type epitaxial layer with the second doping concentration; The surface of the P-type material layer with the first doping concentration includes a plurality of uniformly distributed P-type material regions with the second doping concentration.

2. The fast recovery diode according to claim 1, characterized in that: The first metal layer and the second metal layer are both made of aluminum.

3. A method for manufacturing a fast recovery diode, used for manufacturing the fast recovery diode according to claim 1 or 2, characterized in that: The production method comprises: Providing an N-type substrate material layer; forming an N-type epitaxial layer on the N-type substrate material layer, wherein the doping concentration of the N-type epitaxial layer close to the N-type substrate material layer is less than the doping concentration of the N-type substrate material layer; Implanting a first dose of boron ions on the N-type epitaxial layer to form a P-type material layer with a first doping concentration; Implanting a second dose of boron ions on the surface of the P-type material layer of the first doping concentration to form a P-type material region of the second doping concentration, wherein the doping concentration of the P-type material layer of the first doping concentration is less than the doping concentration of the P-type material region of the second doping concentration, and the doping concentration of the N-type epitaxial layer close to the P-type material layer of the first doping concentration is greater than the doping concentration of the N-type epitaxial layer close to the N-type substrate material layer; Metal is sputtered respectively on a surface of the P-type material layer with the first doping concentration away from the N-type epitaxial layer and a surface of the N-type substrate material layer away from the N-type epitaxial layer to form a corresponding second metal layer and first metal layer.

4. The method according to claim 3, characterized in that: The forming of an N-type epitaxial layer on the N-type substrate material layer comprises: Implanting N-type ions on the N-type substrate material layer and performing annealing to form an N-type epitaxial layer with a first doping concentration; Implanting N-type ions into the N-type epitaxial layer of the first doping concentration and performing annealing to form an N-type drift region; Implanting phosphorus ions into the N-type drift region, and performing annealing to form an N-type epitaxial layer with a second doping concentration; Among them, the doping concentration of the N-type epitaxial layer with the first doping concentration is less than the doping concentration of the N-type substrate material layer, and is greater than the doping concentration of the N-type drift region, and the doping concentration of the N-type drift region is less than the doping concentration of the N-type epitaxial layer with the second doping concentration.

5. The method according to claim 4, characterized in that: The implantation dose of phosphorus ions is 1*10 12 Pieces / cm 2 ~5*10 13 Pieces / cm 2 The energy of the phosphorus ions is between 1.5 MeV and 6 MeV.

6. The method according to claim 3, characterized in that: The step of implanting a first dose of boron ions into the N-type epitaxial layer to form a P-type material layer with a first doping concentration includes: A first dose of boron ions is implanted into the N-type epitaxial layer, and a P-type material layer with a first doping concentration at a first depth is formed after high-temperature annealing, wherein the first dose is 1*10 12 Pieces / cm 2 ~1*10 14 Pieces / cm 2 The first depth is between 3 μm and 10 μm.

7. The manufacturing method according to claim 3, characterized in that: The step of implanting a second dose of boron ions on the surface of the P-type material layer of the first doping concentration to form a P-type material region of the second doping concentration comprises: A second dose of boron ions is implanted on the surface of the P-type material layer with the first doping concentration, and high temperature activation is performed to obtain a plurality of uniformly distributed P-type material regions with the second doping concentration, wherein the second dose is 1*10 14 Pieces / cm 2 ~1*10 15 Pieces / cm 2 The activation temperature of the high temperature activation is between 900° C. and 1000° C., and the time of the high temperature activation is between 30 min and 60 min.

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