IGBT device and method of manufacturing the same

Abstract

The application discloses a manufacturing method of an IGBT device, comprising the following steps: step one, forming a drift region; step two, forming a body region, comprising the following steps: step 21, setting the total injection dose of the body region according to the threshold voltage requirement value met by the threshold voltage of the IGBT device; step 22, splitting the total injection dose into a plurality of single injection doses; step 23, performing more than two times of body region injection of the second conductive type to form the body region, wherein each time of body region injection adopts a corresponding single injection dose, the injection energy of each time of body region injection is different, and the injection energy of each time of body region injection is set according to the length requirement of the conductive channel, the length of the conductive channel is determined by the saturation current of the IGBT, and the injection energy of each time of body region injection is set to reduce the saturation current of the IGBT to the value required by the short-circuit capability; step three, forming a trench gate through the body region; step four, forming an emitter region; and step five, forming a collector region. The application also discloses an IGBT device. The application can improve the short-circuit capability of the device.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of semiconductor integrated circuit manufacturing, and in particular to an insulated gate field effect transistor (IGBT) device; the present application also relates to a manufacturing method of the IGBT device. BACKGROUND

[0002] IGBT is a bipolar device, and because of its current amplification feature, IGBT achieves excellent on-state voltage drop in the medium and high voltage field; and because of its voltage control feature, the driving circuit of IGBT is easier to realize than another bipolar device BJT.

[0003] N-doped drift region.

[0004] P+ doped collector region is located at the back of the drift region, and usually, there is also an N-doped buffer layer between the drift region and the collector region.

[0005] There is an N-doped carrier storage layer with a higher doping concentration than the drift region on the top of the drift region.

[0006] A P-doped body region (Pbody) is formed on the top of the carrier storage layer.

[0007] A trench gate passes through the body region, and the trench gate includes a gate oxide layer formed on the inner side surface of the gate trench and a gate conductive material layer such as a polysilicon gate filled in the gate trench.

[0008] There is an N+ doped emitter region formed on the surface of the body region, and the emitter region is self-aligned with the side surface of the trench gate.

[0009] There is also a P+ doped body lead-out region formed on the surface of the body region.

[0010] There is an emitter composed of a front metal layer formed on the front surface of the emitter region and the body lead-out region. There is a gate composed of a front metal layer formed on the front surface of the polysilicon gate.

[0011] There is a collector composed of a back metal layer formed on the back surface of the collector region.

[0012] In the application topology of IGBT, the device often works in a high voltage and large current state at the same time, which is called short circuit. Taking a 1200V 100A IGBT as an example, when it is in a short circuit state, the voltage between the collector and the emitter is about 600V-800V, and the collector current is much higher than 100A, which can reach thousands of amperes. The voltage of the collector is much higher than that of the emitter, and at this time the IGBT works in the saturation region.

[0013] In saturation state, the MOS channel of IGBT is pinched off, the carrier drift velocity in the pinched-off region reaches saturation, which results in saturation of the channel electron current, and then the current flowing through the IGBT also reaches saturation. Therefore, in saturation state, as long as the voltage difference between the gate and the emitter is unchanged, the saturation current will not change obviously when the collector voltage rises or falls. Therefore, the voltage and current borne by the IGBT in short-circuit process are the bus voltage and the saturation current in the corresponding state, respectively.

[0014] In short-circuit state, high voltage and large current cause the IGBT to generate great power, which can cause the device to heat up sharply and burn out in a very short time. Therefore, the short-circuit capability of the IGBT is usually defined as a certain maintenance time or maintenance power during which the device can work normally in short-circuit state, for example, the short-circuit time can be required to be greater than 10 us, and the IGBT can still work normally after the 10 us short-circuit state ends.

[0015] The method for improving the short-circuit capability of the IGBT is mainly to reduce the short-circuit power of the IGBT. In the case that the bus voltage of the IGBT is unchanged, this means reducing the saturation current. A common method for reducing the saturation current is to control the channel density of the IGBT, but this method has the disadvantage of affecting the on-state voltage drop of the IGBT. SUMMARY

[0016] The technical problem to be solved by the present application is to provide an IGBT device capable of reducing the saturation current of the device and thereby improving the short-circuit capability of the device, while not changing the channel density of the device, so as not to affect the on-state voltage drop of the device. To this end, the present application also provides a manufacturing method of an IGBT device.

[0017] To solve the above technical problem, the IGBT device provided by the present application comprises:

[0018] A drift region composed of a first-conductivity-type lightly doped region formed on the surface of a semiconductor substrate.

[0019] A second-conductivity-type doped body region formed on the surface of the drift region.

[0020] A collector region composed of a second-conductivity-type heavily doped region is formed on the bottom surface of the drift region.

[0021] A trench gate passing through the body region.

[0022] A first-conductivity-type heavily doped emitter region is formed on the surface of the body region, and the emitter region is self-aligned with the side surface of the trench gate.

[0023] The surface of the body region covered by the side surface of the trench gate is used to form a conductive channel.

[0024] The body region is formed by superimposition of body region injection regions formed by 2 or more times of body region injection of the second conductivity type.

[0025] Each of the body region injection regions simultaneously forms a short circuit capability improvement structure and a threshold voltage setting structure of the IGBT device.

[0026] The threshold voltage setting structure is used to make the threshold voltage of the IGBT device satisfy a threshold voltage requirement value, and the threshold voltage is determined by the total injection dose of all times of the body region injection.

[0027] The short circuit capability improvement structure is determined by the injection energy of each of the body region injection, the injection energy of each of the body region injection is different and is set according to the length requirement of the conductive channel, and the setting of the injection energy of each of the body region injection makes the length of the conductive channel increase to make the size of the saturation current of the IGBT satisfy the requirement, so that the short circuit capability of the IGBT device satisfies the requirement.

[0028] Further improvement is that the number of times of the body region injection corresponding to the body region is 2 or 3.

[0029] Further improvement is that the injection energy of the second body region injection is 1.5 times to 2 times of the injection energy of the first body region injection in the order from low to high.

[0030] When the number of times of the body region injection is 3, the injection energy of the third body region injection is 2.5 times to 3.5 times of the injection energy of the first body region injection.

[0031] Further improvement is that the working voltage of the IGBT device is 600V to 1700V.

[0032] Further improvement is that the threshold voltage requirement value is 8V or less.

[0033] Further improvement is further comprising: a first conductive type carrier storage layer, the carrier storage layer is formed at the top region of the drift region and is located at the bottom of the body region, and the doping concentration of the carrier storage layer is greater than the doping concentration of the drift region.

[0034] Further improvement is that the difference between the single injection dose corresponding to each of the body region injection is less than or equal to 1e13cm -2 .

[0035] Further improvement is that the first conductivity type is N type and the second conductivity type is P type, or the first conductivity type is P type and the second conductivity type is N type.

[0036] To solve the above technical problems, the application provides a manufacturing method of IGBT device, which comprises the following steps:

[0037] Step one, providing a semiconductor substrate, and forming a drift region composed of a first conductive type lightly doped region on the surface of the semiconductor substrate.

[0038] Step two, forming a second conductive type doped body region on the surface of the drift region, which comprises the following sub-steps:

[0039] Step 21, setting the total injection dose of the body region according to the threshold voltage requirement value met by the threshold voltage of the IGBT device.

[0040] Step 22, splitting the total injection dose into a plurality of single injection doses.

[0041] Step 23, forming the body region through 2 or more times of second conductive type body region injection.

[0042] Each time of the body region injection adopts a corresponding single injection dose; the injection energy of each time of the body region injection is different and is set according to the length requirement of the conductive channel, the length of the conductive channel is determined by the saturation current of the IGBT, and the injection energy of each time of the body region injection is set to reduce the saturation current of the IGBT to the required value of short circuit capability.

[0043] Step three, forming a trench gate through the body region; the surface of the body region covered by the side surface of the trench gate is used to form the conductive channel.

[0044] Step four, forming a first conductive type heavily doped emitter region on the surface of the body region, and the emitter region and the side surface of the trench gate are self-aligned.

[0045] Step five, forming a second conductive type heavily doped collector region composed of a heavily doped region on the bottom surface of the drift region.

[0046] Further improvement is that the number of times of the body region injection corresponding to the body region is 2 or 3.

[0047] Further improvement is that the injection energy of the second time of the body region injection is 1.5 times to 2 times of the injection energy of the first time of the body region injection in the order from low to high.

[0048] When the number of times of the body region injection is 3, the injection energy of the third time of the body region injection is 2.5 times to 3.5 times of the injection energy of the first time of the body region injection.

[0049] Further improvement is that the working voltage of the IGBT device is 600V to 1700V.

[0050] Further improvement is that the threshold voltage requirement value is 8V or less.

[0051] Further improvement is that it further comprises: a first conductive type doped carrier storage layer, which is formed on the top region of the drift region and at the bottom of the body region, and the doping concentration of the carrier storage layer is greater than the doping concentration of the drift region.

[0052] Further improvement is that the difference between the corresponding single implant dose of each body region injection is less than or equal to 1e13cm -2 .

[0053] Further improvement is that it further comprises: before step one, it further comprises a simulation step of selecting the total implant dose and the corresponding single implant dose of each time:

[0054] Set a plurality of total implant dose and the corresponding single implant dose of each time; one total implant dose and the corresponding single implant dose of each time as a group of implant conditions.

[0055] The simulation values of the saturation current, threshold voltage and on-state voltage drop of the IGBT device corresponding to each group of implant conditions are obtained by simulation.

[0056] According to the simulation values of the saturation current, threshold voltage and on-state voltage drop of the IGBT device, at least one group of total implant dose and the corresponding single implant dose of each time of the implant conditions is selected as the total implant dose and the single implant dose of each time used in step two.

[0057] Further improvement is that in the simulation step:

[0058] It further comprises setting the implant energy in each group of implant conditions, and the implant energy corresponding to the body region with the same injection sequence number in each group of implant conditions is the same.

[0059] The structure of the body region is specially set in the present application, and the body region is formed by the superposition of the body region injection zones formed by two or more times of body region injection. The threshold voltage setting structure and the short circuit capability improving structure are formed at the same time by the superposition of the body region injection zones. The threshold voltage setting structure is formed by making the total implant dose of each time of body region injection meet the requirement of threshold voltage. On this basis, the superposition of each time of body region injection zone can increase the body region junction depth and the conductive channel length. The increase of the conductive channel length can reduce the saturation current to improve the short circuit capability of the device, so as to realize the short circuit capability improving structure. Therefore, the present application can reduce the saturation current of the device, and further reduce the heat power in the short circuit process, so as to increase the short circuit time and improve the short circuit capability of the device.

[0060] Meanwhile, since the application only needs to set the process structure of the body region to reduce the saturation current, and does not need to reduce the saturation current by reducing the channel density, the setting of the channel density is not limited by the reduction of the saturation current, so that the channel density can adapt to the requirement of improving the on-voltage drop of the device, and the application can also not change the channel density of the device, thereby not affecting the on-voltage drop of the device, and finally improving the comprehensive performance of the device and expanding the application range. BRIEF DESCRIPTION OF DRAWINGS

[0061] The application will be further described in detail below in combination with the drawings and specific embodiments:

[0062] Figure 1 is a structure schematic diagram of an embodiment of an IGBT device of the application;

[0063] Figure 2 is a flowchart of a manufacturing method of an embodiment of an IGBT device of the application;

[0064] Figure 3 is a saturation current curve formed under each group of injection conditions in the simulation step of the manufacturing method of an embodiment of an IGBT device of the application. DETAILED DESCRIPTION

[0065] As shown in Figure 1 is a structure schematic diagram of an embodiment of an IGBT device of the application; the embodiment of the IGBT device of the application comprises:

[0066] The drift region 101 is composed of a first-conductivity-type lightly doped region formed on the surface of a semiconductor substrate.

[0067] The body region 103 doped with a second-conductivity type is formed on the surface of the drift region 101.

[0068] The collector region 110 composed of a second-conductivity-type heavily doped region is formed on the bottom surface of the drift region 101.

[0069] The trench gate passing through the body region 103.

[0070] The emitter region 107 doped with a first-conductivity type is formed on the surface of the body region 103, and the emitter region 107 is self-aligned with the side surface of the trench gate.

[0071] The surface of the body region 103 covered by the side surface of the trench gate is used to form a conductive channel.

[0072] The body region 103 is composed of a body region injection region formed by more than two times of body region injection of a second-conductivity type.

[0073] The body region implantation forms a short circuit capability improving structure and a threshold voltage setting structure of the IGBT device.

[0074] The threshold voltage setting structure is used to make the threshold voltage of the IGBT device meet the threshold voltage requirement value, and the threshold voltage is determined by the total injection dose of all times of body region implantation.

[0075] The short circuit capability improving structure is determined by the implantation energy of each time of body region implantation, the implantation energy of each time of body region implantation is different, and the implantation energy of each time of body region implantation is set according to the length requirement of the conductive channel. The implantation energy of each time of body region implantation is set to increase the length of the conductive channel to make the size of the saturation current of the IGBT meet the requirement, so that the short circuit capability of the IGBT device meets the requirement.

[0076] In some embodiments, the number of times of body region implantation corresponding to the body region 103 is 2 times. In other embodiments, the number of times of body region implantation corresponding to the body region 103 is 3 times.

[0077] In order of implantation energy from low to high, the implantation energy of the second time of body region implantation is 1.5 times to 2 times the implantation energy of the first time of body region implantation.

[0078] When the number of times of body region implantation is 3 times, the implantation energy of the third time of body region implantation is 2.5 times to 3.5 times the implantation energy of the first time of body region implantation.

[0079] In the embodiment of the present application, it also includes: a first conductive type doped carrier storage layer 102, which is formed on the top region of the drift region 101 and at the bottom of the body region 103, and the doping concentration of the carrier storage layer 102 is greater than the doping concentration of the drift region 101.

[0080] There is also a buffer layer 104 doped with the first conductive type between the collector region 110 and the drift region 101.

[0081] The trench gate includes a gate dielectric layer 105 such as a gate oxide layer formed on the inner side surface of the gate trench and a gate conductive material layer 106 such as a polysilicon gate filled in the gate trench.

[0082] There is also a body lead-out region 108 doped with the second conductive type and heavily doped on the surface of the body region 103.

[0083] The emitter region 107 and the body lead-out region 108 are connected with the emitter composed of the front metal layer 109.

[0084] The gate conductive material layer 106 is connected with the gate composed of the front metal layer 109. Figure 1 In the cross-sectional structure, only the front metal layer 109 corresponding to the emitter is shown, and the front metal layer 109 corresponding to the gate is not shown.

[0085] The collector electrode is formed on the back surface of the collector region 110 by a back surface metal layer 111.

[0086] In the embodiment, the first conductive type is N type and the second conductive type is P type. In other embodiments, the first conductive type can be P type and the second conductive type can be N type.

[0087] In some embodiments, the working voltage of the IGBT device is 600V-1700V.

[0088] The threshold voltage requirement is 8V or less.

[0089] The difference between the corresponding single injection dose of each body region injection is less than or equal to 1e13cm -2 .

[0090] The embodiment of the present application specially sets the structure of the body region 103, and the body region 103 is formed by the superposition of body region injection regions formed by two or more times of body region injection. The superposition of the body region injection regions is used to form the threshold voltage setting structure and the short circuit capability improving structure. The threshold voltage setting structure is formed by making the sum of the injection dose of each time of body region injection meet the threshold voltage requirement. On this basis, the superposition of each time of body region injection region can increase the junction depth of the body region 103 and the conductive channel length. The increased conductive channel length can be used to reduce the saturation current to improve the short circuit capability of the device, thereby realizing the short circuit capability improving structure. Therefore, the embodiment of the present application can reduce the saturation current of the device, and further reduce the heat power in the short circuit process, thereby increasing the short circuit time and improving the short circuit capability of the device.

[0091] Meanwhile, since the embodiment of the present application only needs to set the process structure of the body region 103 to reduce the saturation current, and does not need to reduce the saturation current by reducing the channel density, the setting of the channel density is not limited by the reduction of the saturation current, so that the channel density can adapt to the requirement of improving the on-voltage drop of the device. Therefore, the embodiment of the present application can also not change the channel density of the device, thereby not affecting the on-voltage drop of the device, and finally improving the comprehensive performance of the device and expanding the application range.

[0092] As shown in Figure 2 , it is a flow chart of the manufacturing method of the IGBT device of the embodiment of the present application. The structure of the formed IGBT device is shown in Figure 1 ; the manufacturing method of the IGBT device of the embodiment of the present application includes the following steps:

[0093] Step one, providing a semiconductor substrate, forming a drift region 101 composed of a first conductive type lightly doped region on the surface of the semiconductor substrate.

[0094] The method of the embodiment of the present application further comprises a first conductive type doped carrier storage layer 102 formed on the top of the drift region 101 and at the bottom of the body region 103 after the formation of the drift region 101 and before the formation of the body region 103, wherein the doping concentration of the carrier storage layer 102 is greater than the doping concentration of the drift region 101.

[0095] Step two, forming a body region 103 of the second conductive type on the surface of the drift region 101, comprising the following steps:

[0096] Step 21, setting the total injection dose of the body region 103 according to the threshold voltage requirement value satisfied by the threshold voltage of the IGBT device.

[0097] Step 22, splitting the total injection dose into a plurality of single injection doses.

[0098] Step 23, performing two or more body region injections of the second conductive type to form the body region 103.

[0099] Each body region injection adopts a corresponding single injection dose, and the injection energy of each body region injection is different and is set according to the length requirement of the conductive channel, which is determined by the saturation current of the IGBT, so that the saturation current of the IGBT is reduced to the value required by the short-circuit capability.

[0100] In some embodiment methods, the number of body region injections corresponding to the body region 103 is two. In other embodiment methods, the number of body region injections corresponding to the body region 103 is three.

[0101] In the order from low to high injection energy, the injection energy of the second body region injection is 1.5 to 2 times the injection energy of the first body region injection.

[0102] When the number of body region injections is three, the injection energy of the third body region injection is 2.5 to 3.5 times the injection energy of the first body region injection.

[0103] In some embodiment methods, the working voltage of the IGBT device is 600 to 1700 V.

[0104] The threshold voltage requirement value is 8 V or less.

[0105] The difference between the single injection doses corresponding to each two body region injections is less than or equal to 1e13 cm -2 .

[0106] Step three, forming a trench gate through the body region 103, and the surface of the body region 103 covered by the side surface of the trench gate is used to form a conductive channel.

[0107] The method of the embodiment of the present application comprises the following steps:

[0108] Forming a gate trench.

[0109] Forming a gate dielectric layer 105 on the inner surface of the gate trench. In some embodiments, the gate dielectric layer 105 is an oxide layer.

[0110] Filling the gate trench with a gate conductive material layer 106. In some embodiments, the gate conductive material layer 106 is a polysilicon gate.

[0111] In some embodiments, the order of steps two and three can be interchanged.

[0112] Step four, forming a first conductive type heavily doped emitter region 107 on the surface of the body region 103, the emitter region 107 and the side surface of the trench gate are self-aligned.

[0113] In some embodiments, the method further comprises forming a second conductive type heavily doped body lead-out region 108 on the surface of the body region 103.

[0114] Then, the front side process is completed. The front side process comprises forming a front side metal layer 109 and patterning the front side metal layer 109 to form a gate and an emitter.

[0115] The emitter region 107 and the body lead-out region 108 are connected to the emitter.

[0116] The gate conductive material layer 106 is connected to the gate.

[0117] Then, the back side process is continued, which comprises:

[0118] Thinning the semiconductor substrate from the back side. Then, the following step five is performed.

[0119] Step five, forming a collector region 110 composed of a second conductive type heavily doped region on the bottom surface of the drift region 101.

[0120] The collector region 110 is formed by back side ion implantation.

[0121] Then, a back side metal layer 111 is formed, and the collector electrode is composed of the back side metal layer 111.

[0122] In some embodiments, the method further comprises the following steps before step one:

[0123] Setting a plurality of implant dose sums and corresponding single implant doses for each implant dose sum; and taking one implant dose sum and corresponding single implant doses as a group of implant conditions.

[0124] The injection energy in each group of injection conditions is set, and the body region with the same sequence number in each group of injection conditions is injected with the same corresponding injection energy.

[0125] Simulation is performed to obtain simulation values of the saturation current, threshold voltage and on-state voltage drop of the IGBT device corresponding to each group of injection conditions. The simulation values are shown in Table 1 described later.

[0126] According to the simulation values of the saturation current, threshold voltage and on-state voltage drop of the IGBT device, the injection dose sum of at least one group of injection conditions and the corresponding single injection dose of each time are selected as the injection dose sum and the single injection dose of each time used in step 2.

[0127] In the embodiment method of the present application, the first conductivity type is N type, and the second conductivity type is P type. In other embodiment methods, the first conductivity type can be P type, and the second conductivity type can be N type.

[0128] The embodiment method of the present application forms the Pbody (body region 103) by performing multiple injections, increases the length of the channel (conductive channel) and the threshold voltage, and reduces the saturation current of the IGBT.

[0129] As shown in Table 1 below, the structure of a 1200V 100A pitch 3μm IGBT is simulated and analyzed, and the effects of different Pbody process conditions on the parameters such as the saturation current, threshold voltage and on-state voltage drop of the device are compared.

[0130] Table 1

[0131]

[0132] In Table 1, the numbers 1 to 6 represent the numbers of the six groups of injection conditions. The Pbody1 injection condition table shows the injection conditions of the first body region injection, the Pbody2 injection condition table shows the injection conditions of the second body region injection, and the body region 103 corresponds to two times of body region injection. The injection energy and injection dose given in the injection conditions of the two times of body region injection are, for example, in the Pbody1 injection condition of number 1, 80keV represents the injection energy, and 2.7e13 cm -2 represents the injection dose; the Pbody2 injection condition is 0, which means that the second body region injection is not performed, which means that the injection condition corresponding to number 1 is the injection condition corresponding to the existing method, which is used for comparison with the subsequent five injection conditions in order to select the injection conditions required by the embodiment method of the present application. In numbers 2 to 5, the injection energy of the first body region injection is 80keV, and the injection energy of the second body region injection is 150keV, and the injection energy of the second time is larger.

[0133] Comparing the injection conditions of No. 1 and No. 2, we can see that the total injection dose of the two body injections of No. 2 is 3.0e13 cm -2 , which is greater than 2.7e13 cm of No. 1 -2 Finally, the threshold voltage corresponding to number 2 will increase, for example, to 7.0V, but the saturation current will decrease, for example, to 674A.

[0134] like Figure 3 2 is a saturation current curve 201 formed under various injection conditions in the simulation steps of the method for manufacturing an IGBT device according to an embodiment of the present invention. Curve 201 is obtained based on the saturation current corresponding to numbers 1 to 6 in Table 1.

[0135] The simulation results in Table 1 compare the effects of single or double injections (different injection energies for the two Pbody injections, with the second injection energy being greater than the first) and the Pbody dose on different static parameters. -2 and 150KeV / 1.5e13cm -2 ) and an increase in the Pbody dose, compared to a single Pbody implant, the saturation current is reduced by over 26%, the threshold voltage (Vth) increases by no more than 8%, and the on-state voltage drop (Vcesat) increases by no more than 2.5%. If the Pbody dose or number of implants continues to increase, the product's threshold voltage and on-state voltage drop will continue to increase. Therefore, simulation results can be used to select suitable or optimal implant conditions for the body region 103.

[0136] In the method of the embodiment of the present invention, Pbody injection can be performed 2 to 3 times, and the total Pbody dose is greater than the Pbody dose when only one injection is performed, and is approximately 1.2 to 1.5 times that of a single injection. The injection energy of each of the multiple Pbody injections is different, and the second injection energy is approximately 1.5 to 2 times the first injection energy; the third injection energy is approximately 2.5 to 3.5 times the first injection energy. The Vth range needs to be controlled during multiple Pbody injections, and the Vth should be controlled within a reasonable application range. For 650V / 1200V IGBTs, the Vth should be controlled below 8.0V.

[0137] Finally, by adopting the method of the embodiment of the present invention, the saturation current of the IGBT can be controlled, thereby reducing the heat power generated by the IGBT during the short-circuit process, and increasing the short-circuit time and short-circuit capacity.

[0138] The application is described in detail above with specific examples, but these do not constitute a limitation on the application. Those skilled in the art can make many modifications and improvements without departing from the principles of the application, and these should be considered as within the scope of the application.

Claims

1. An IGBT device, characterized in that: include: a drift region, consisting of a lightly doped region of the first conductivity type formed on the surface of the semiconductor substrate; A body region doped with a second conductivity type, formed on the surface of the drift region; A collector region composed of a heavily doped region of the second conductive type is formed on the bottom surface of the drift region; a trench gate passing through the body region; An emitter region heavily doped with a first conductivity type is formed on the surface of the body region, and the emitter region is self-aligned with the side surface of the trench gate; The surface of the body region covered by the side surface of the trench gate is used to form a conductive channel; The body region is formed by superimposing body region injection regions formed by 2 or 3 times of second conductivity type body region injection; Each of the body region injection regions simultaneously forms a short-circuit capability enhancement structure and a threshold voltage setting structure of the IGBT device; The threshold voltage setting structure is used to make the threshold voltage of the IGBT device meet the threshold voltage requirement value, and the threshold voltage is determined by the sum of the implantation doses of all times of the body region implantation; The short-circuit capability enhancement structure is determined by the injection energy of each body region injection, the injection energy of each body region injection is different and the injection energy of each body region injection is set according to the length requirement of the conductive channel, and the setting of the injection energy of each body region injection increases the length of the conductive channel to the extent that the saturation current of the IGBT meets the requirement, so that the short-circuit capability of the IGBT device meets the requirement; Arranged in order of injection energy from low to high, the injection energy of the second body region injection is 1.5 to 2 times the injection energy of the first body region injection; When the number of body region injections is three, the injection energy of the third body region injection is 2.5 to 3.5 times the injection energy of the first body region injection; The difference in single injection dose between each of the body regions is less than or equal to 1e13 cm -2 .

2. The IGBT device according to claim 1, wherein: The operating voltage of the IGBT device is 600V to 1700V.

3. The IGBT device according to claim 2, wherein: The threshold voltage is required to be below 8V.

4. The IGBT device according to claim 1, wherein: Also includes: A carrier storage layer doped with a first conductive type is formed in a top area of ​​the drift region and located at the bottom of the body region, and a doping concentration of the carrier storage layer is greater than a doping concentration of the drift region.

5. The IGBT device according to any one of claims 1 to 4, characterized in that: The first conductivity type is N-type, and the second conductivity type is P-type; or, the first conductivity type is P-type, and the second conductivity type is N-type.

6. A method for manufacturing an IGBT device, characterized in that: The steps include: Step 1: providing a semiconductor substrate, and forming a drift region consisting of a lightly doped region of the first conductivity type on the surface of the semiconductor substrate; Step 2: forming a body region doped with a second conductivity type on the surface of the drift region, including the following steps: Step 21, setting the total implantation dose of the body region according to the threshold voltage requirement value satisfied by the threshold voltage of the IGBT device; Step 22: splitting the total injection dose into multiple single injection doses; Step 23, implanting a body region of the second conductivity type twice or three times to form the body region; Each of the body region implantations uses a corresponding single implantation dose; the implantation energy of each of the body region implantations is different and is set according to a length requirement of a conductive channel, the length of the conductive channel being determined by a saturation current of the IGBT, and the implantation energy of each of the body region implantations is set so as to reduce the saturation current of the IGBT to a value required for short-circuit capability; Arranged in order of injection energy from low to high, the injection energy of the second body region injection is 1.5 to 2 times the injection energy of the first body region injection; When the number of body region injections is three, the injection energy of the third body region injection is 2.5 to 3.5 times the injection energy of the first body region injection; The difference in single injection dose between each of the body regions is less than or equal to 1e13 cm -2 ; Step 3: forming a trench gate passing through the body region; the surface of the body region covered by the side surface of the trench gate is used to form the conductive channel; Step 4: forming an emitter region heavily doped with the first conductivity type on the surface of the body region, wherein the emitter region is self-aligned with the side surface of the trench gate; Step 5: forming a collector region composed of a heavily doped region of the second conductive type on the bottom surface of the drift region.

7. The method for manufacturing an IGBT device according to claim 6, wherein: The operating voltage of the IGBT device is 650V to 1200V.

8. The method for manufacturing an IGBT device according to claim 7, wherein: The threshold voltage is required to be below 8V.

9. The method for manufacturing an IGBT device according to claim 6, wherein: Also includes: A carrier storage layer doped with a first conductive type is formed in a top area of ​​the drift region and located at the bottom of the body region, and a doping concentration of the carrier storage layer is greater than a doping concentration of the drift region.

10. The method for manufacturing an IGBT device according to claim 9, wherein: Also includes: Before performing step 1, the method further includes the following steps: selecting the total injection dose and the corresponding single injection doses; Setting a sum of multiple injection doses and each single injection dose corresponding to each sum of the injection doses; The total amount of the injection dose and the single injection dose corresponding to each injection are used as a set of injection conditions; Performing simulation to obtain simulation values ​​of the saturation current, threshold voltage, and on-state voltage drop of the IGBT device corresponding to each group of the injection conditions; According to the simulation values ​​of the saturation current, threshold voltage and on-state voltage drop of the IGBT device, the total injection dose of at least one set of the injection conditions and the corresponding single injection doses are selected as the total injection dose and the single injection dose used in step 2.

11. The method for manufacturing an IGBT device according to claim 10, wherein: In the simulation steps: The method further includes setting the injection energy in each group of the injection conditions, wherein the injection energy corresponding to the body region injection with the same injection sequence number in each group of the injection conditions is the same.

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