CN111682063B - Ultrahigh-voltage P-channel SiC-IGBT device material and manufacturing method thereof - Google Patents
Ultrahigh-voltage P-channel SiC-IGBT device material and manufacturing method thereof Download PDFInfo
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- H01L29/70—Bipolar devices
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- H01L29/739—Transistor-type devices, i.e. able to continuously respond to applied control signals controlled by field-effect, e.g. bipolar static induction transistors [BSIT]
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- H01L29/66234—Bipolar junction transistors [BJT]
- H01L29/66325—Bipolar junction transistors [BJT] controlled by field-effect, e.g. insulated gate bipolar transistors [IGBT]
Abstract
The invention relates to the technical field of P-channel SiC-IGBT devices, in particular to an ultrahigh pressure P-channel SiC-IGBT device material and a manufacturing method thereof, wherein the ultrahigh pressure P-channel SiC-IGBT device material comprises the following material layers which are sequentially laminated from bottom to top: a silicon carbide substrate; n + buffer layer with thickness of 0.8-1.2 μm, Si/C ratio of 0.9-1.01, and N as doping gas2Has a doping concentration of (1.5-2.5) × 1018cm‑3(ii) a A P + buffer layer; the thickness of the P-pressure-resistant layer is more than 250 micrometers, and the carbon-silicon ratio is 1.32-1.50; and a P-collector layer. According to the invention, the thickness of the P-voltage-resistant layer is increased, and the design thickness is more than 250 μm, so that the P-channel SiC-IGBT device material can bear 25kV voltage which is far higher than the 15kV voltage-resistant value of the existing common P-channel IGBT device material.
Description
Technical Field
The invention relates to the technical field of P-channel SiC-IGBT devices, in particular to an ultrahigh-voltage P-channel SiC-IGBT device material and a manufacturing method thereof.
Background
Silicon carbide (SiC) is a third generation semiconductor material that has superior physical and electrical properties to the first generation semiconductor materials silicon, germanium, and the second generation semiconductors gallium arsenide and indium phosphide. The silicon carbide has the characteristics of high critical breakdown electric field, large forbidden band width, high thermal conductivity, high electron saturation migration rate and the like, and the unique advantages enable the silicon carbide to be applied to the application fields of high power, high temperature, high pressure, radiation resistance and the like.
At present, a solid-state mainstream device applied in the field of power electronics is a Si-IGBT, and the turn-off voltage of the solid-state mainstream device is 0.6-6.5 kV. After the development of thirty years, the Si-IGBT has reached the limits of performance and device structure, and with the rise of new fields of electric automobiles, photovoltaics, wind energy green energy, power grids and the like, the power electronic devices are required to have better material performance. The SiC-IGBT device has the unique material characteristics and the structural characteristics, has the advantages of high switching speed, simple driving and high input impedance of the MOSFET, and also has the advantages of large current capacity and low conduction voltage drop of a bipolar device. Therefore, the SiC-IGBT is very suitable for the field developing towards high voltage, high frequency, large current and high power.
There are two types of SiC-IGBT devices: one is a P-channel IGBT, and the other is an N-channel IGBT. The P-IGBT requires a P-type doped silicon carbide epitaxial layer, and the N-IGBT requires a P-type highly doped silicon carbide epitaxial layer and an N-type doped epitaxial layer; however, the P-type silicon carbide substrate with low resistivity is required for manufacturing the material of the N-channel IGBT device, the resistivity of the currently produced P-type silicon carbide substrate is about 50 times higher than that of the N-type substrate, and the material of the N-channel IGBT device needs to use a structure of a reverse N-channel IGBT device, so that the manufacturing process is complex. The fabrication of an N-channel IGBT device on a P-type silicon carbide substrate also introduces a very large series resistance (0.8-1.0 Ω -cm)2) Thereby increasing the loss of the device. The P-channel has higher transconductance and larger saturation current than the N-channel IGBT.
Compared with an N-channel IGBT, the P-channel IGBT device material is simpler in manufacturing process, and a P-type voltage-resisting layer can be epitaxially grown on an N-type substrate with good quality, so that the P-IGBT can obtain a plurality of excellent performances.
For the P-IGBT, the high withstand voltage and the low on-resistance are developed from the beginning of the 21 st century to the present, the voltage is increased from 6kV to 15kV, and the specific on-resistance is also 570m omega cm2Reduced to 18m omega cm2. In order to pursue lower on-resistance, ion implantation of the collector must be increased, so that after the device is turned off, more excess carriers are stored in the voltage-withstanding layer, and the turn-off time is prolonged. Meanwhile, in order to bear higher breakdown voltage, the SiC-IGBT needs a thicker voltage-withstanding layer, and the voltage-withstanding layers of the currently reported P-channel IGBT devices are all about 100 μm at most. The crystal quality of the thick epitaxial layer material obtained at present is poor, the growth time is long, the performance of the device is poor, the yield is low, and the popularization and the application of the SiC-IGBT are not facilitated.
Disclosure of Invention
In order to overcome the defects and shortcomings in the prior art, the invention aims to provide an ultrahigh voltage P-channel SiC-IGBT device material, and the invention also aims to provide a preparation method of the ultrahigh voltage P-channel SiC-IGBT device material, wherein the ultrahigh voltage P-channel SiC-IGBT device material has the advantages of high withstand voltage value, large saturation current, low series resistance and the like.
The purpose of the invention is realized by the following technical scheme:
the ultrahigh pressure P channel SiC-IGBT device material comprises the following material layers which are sequentially stacked from bottom to top:
a silicon carbide substrate;
n + buffer layer with thickness of 0.8-1.2 μm, Si/C ratio of 0.9-1.01, and N as doping gas2Has a doping concentration of (1.5-2.5) × 1018cm-3；
A P + buffer layer;
the thickness of the P-pressure-resistant layer is more than 250 micrometers, and the carbon-silicon ratio is 1.32-1.50;
and a P-collector layer.
The concentration difference between the prior substrate and the P + buffer layer is generally 6e18/cm-3The invention adds a layer of N + buffer layer between the silicon carbide substrate and the P + buffer layer, the concentration difference between the N + buffer layer and the P + buffer layer is smaller, the crystal defect caused by overlarge concentration difference between the substrate and the P + buffer layer can be inhibited, and a foundation is provided for growing a high-thickness P-voltage-resistant layer; then, the thickness of the P-voltage-resistant layer is increased, the design thickness is more than 250 micrometers, and the P-channel SiC-IGBT device material can bear the voltage of 25kV, which is far higher than the 15kV voltage-resistant value of the existing common P-channel IGBT device material.
Further, the thickness of the P-voltage-withstanding layer can be, but is not limited to, 250-300 μm, such as 250 μm, 260 μm, 265 μm, 270 μm, 275 μm, 280 μm, 290 μm, 300 μm, etc.
A manufacturing method of an ultrahigh pressure P channel SiC-IGBT device material comprises the following steps:
(1) selecting a silicon carbide substrate and placing the silicon carbide substrate in a reaction chamber;
(2) introducing hydrogen into the reaction chamber, heating the reaction chamber, controlling the pressure of the reaction chamber, introducing HCl gas to perform etching treatment in the heating process of the reaction chamber, and turning off the HCl gas after the temperature is raised to a set value; according to the invention, the HCl gas and the hydrogen gas are adopted for etching, so that the etching capability is stronger compared with that of pure hydrogen, fine scratches and particles on the surface of the substrate can be efficiently removed, and better conditions are provided for the deposition of the N + buffer layer;
(3) depositing an N + buffer layer with a thickness of more than 1 μm on the silicon carbide substrate by chemical vapor deposition, wherein the growth gas is C2H4And SiHCl3Doping source gas is N2Controlling the Si/C ratio to 0.9-1.01 and the doping concentration to (1.5-2.5) × 10 by setting the gas flow rates of the growth gas and the doping source18cm-3(ii) a In addition, the thickness of the N + buffer layer is limited to be more than 1 mu m, so that dislocation defects derived from the substrate can be effectively reduced by the N + buffer layer with the thickness of more than 1 mu m, the thickness is continuously increased after the thickness exceeds 1 mu m, and the improvement of the inhibition effect is not obvious, so that the purposes of saving cost and reducing process difficulty are achieved, and the thickness of the N + buffer layer can be set to be, but not limited to, less than 1.5 mu m, such as 1.1 mu m, 1.2 mu m, 1.3 mu m, 1.4 mu m, 1.5 mu m and the like;
(4) depositing a P + buffer layer with a thickness of 1.8-2.2 μm on the N + buffer layer by chemical vapor deposition method with growth gas of C2H4And SiHCl3The dopant source gas is Al (CH)3)3Controlling the Si/C ratio to 1.0-1.1 and the doping concentration to (1.5-2.5) × 10 by setting the gas flow rates of the growth gas and the doping source17cm-3(ii) a The invention can achieve the purpose of reducing crystal defects and improving the P-type doping efficiency by controlling the silicon-carbon ratio and the doping concentration, and in addition, the invention limits the thickness of the P + buffer layer to be 1.8-2.2 mu m, can effectively eliminate the parasitic latch-up effect in an IGBT device, and has no obvious effect when the thickness is less than 1.8 mu m or more than 2.2 mu m;
(5) depositing a P-pressure-resistant layer with the thickness of more than 250 mu m and the roughness of 1-2nm on the P + buffer layer by adopting a chemical vapor deposition method, wherein the growth gas is C2H4And SiHCl3The dopant source gas is Al (CH)3)3Controlling the Si/C ratio to 1.32-1.50 and the doping concentration to be less than 5 x 10 by setting the gas flow rates of the growth gas and the doping source14cm-3(ii) a The invention controls the roughness of the P-voltage-resistant layer to be 1-2nm,the surface energy can be reduced, defects are not easy to deposit and form on the P + buffer layer, the number of the defects is reduced, and then a P-voltage-resistant layer with the thickness of more than 250 micrometers can be deposited on the P + buffer layer by controlling the silicon-carbon ratio and the doping concentration, so that the purpose of improving the voltage-resistant value of a device material is achieved;
(6) after the growth is finished, the growth gas is cut off, the device material is taken out for chemical mechanical polishing treatment, then the device material is placed in a reaction chamber, and the step (2) is repeated; the polishing treatment can remove pit-shaped defects on the surface, reduce the roughness and facilitate the deposition of a P-collector layer;
(7) depositing a P-collector layer on the P-voltage-resistant layer by chemical vapor deposition, wherein the growth gas is C2H4And SiHCl3The dopant source gas is Al (CH)3)3Controlling the Si/C ratio to 1.0-1.1 and the doping concentration to (7.5-8.5) × 10 by setting the gas flow rates of the growth gas and the doping source15cm-3Annealing treatment is carried out after growth is finished; by controlling the silicon-carbon ratio and the doping concentration, the invention can achieve the purpose of reducing crystal defects and can also improve the P-type doping efficiency;
(8) and after the temperature of the reaction chamber is reduced to a set value, taking the plate to obtain the ultrahigh pressure P channel SiC-IGBT device material.
The invention adopts the chemical vapor deposition method and obtains the high-quality thick epitaxial material with the thickness close to 250 mu m by controlling the silicon-carbon ratio and the doping concentration of each material layer, and the thick epitaxial material has the following advantages:
1. the withstand voltage value of the device material is higher, reaches 25kV and is far higher than the withstand voltage value of the existing P-channel IGBT material about 15 kV;
2. the saturation current of the device material is larger and reaches 230A/cm2Is much higher than the prior P-channel IGBT material by 200A/cm2Left and right saturated current values;
3. the series resistance of the device material is lower at 18m omega cm2On the other hand, the series resistance of the prior art IBGT device using P-type substrate as N-channel silicon carbide is generally 800-2。
In the step (1), the selected silicon carbide substrate is an N-type silicon carbide substrate which is 4-8 inches and is deviated towards the <11-20> direction by 2-5 degrees. Further preferably, a 6 inch N-type silicon carbide substrate biased 4 ° to the <11-20> direction is selected.
Wherein, in the step (2), the introduced hydrogen flow is 130-150L/min, the pressure of the reaction chamber is controlled to be less than 80mbar, then the temperature of the reaction chamber is increased to be above 1400 ℃, HCl gas is introduced according to the flow of 5-10ccm/min, the temperature is continuously increased to be above 1700 ℃, and the HCl gas is cut off. The HCL etching substrate before growth has higher etching speed and stronger effect than that of pure hydrogen, and partial crystal defects and scratches and particulate matters can be obviously reduced and removed by controlling the parameter conditions of the etching process.
Wherein, in the step (3), the temperature of the reaction chamber is maintained above 1700 ℃, and then growth gas and doping source gas, C, are introduced2H4And SiHCl3The flow rates of the two are respectively 7-10ccm/min and 20-25ccm/min, N2The flow rate is 120-; after the growth is finished, keeping hydrogen to be introduced, shutting off other gases, and performing pressure-temperature circulation for 2 times, wherein the pressure-temperature circulation is performed by: the pressure in the reaction chamber is increased to 400-700mbar, the temperature is reduced to 1300-1500 ℃, and then the pressure in the reaction chamber is reduced to below 80mbar, and the temperature is increased to above 1700 ℃. Through the cooling that steps up repeatedly, reduce the adsorption affinity of particulate matter on the epitaxial layer, do benefit to sweeping of carrier gas hydrogen clean, the tiny particulate matter that falls on the buffer layer when showing the reduction growth avoids the particulate matter can form the defect in growth that follows.
Wherein, in the step (4), the temperature of the reaction chamber is maintained above 1700 ℃ and the pressure is maintained below 80mbar, and then growth gas and doping source gas, C, are introduced2H4And SiHCl3The flow rates of the components are respectively 14-18ccm/min and 30-50ccm/min, and Al (CH)3)3The flow rate is 150-; keeping hydrogen gas introduction, cutting off other gas, keeping for 1.5-2.5min, and introducing C of 6-8ccm/min2H4And is turned off after being maintained for 8-12s2H4. The operation of the step after the growth is to introduce carbon atoms to fill small pits on the epitaxial layer, reduce pit defects,since these defects will further propagate on the subsequent voltage-withstanding layer, affecting the crystal quality.
Wherein, in the step (5), the temperature of the reaction chamber is first reduced to 1500-2H4The flow rate of the growth gas is slowly increased from 14 to 18ccm/min to 220 + 280ccm/min, and SiHCl is grown3The flow rate of Al (CH) is slowly increased from 30-50ccm/min to 490-520ccm/min3)3The flow rate is less than 20 ccm/min. The lift rate of the growth gas can be set to, but is not limited to, 1.6-2.3 ccm/s. The invention is realized by gradually increasing the growth gas C2H4And SiHCl3The flow can improve the growth rate of the P-pressure-resistant layer, the total growth rate reaches 90 mu m/h and is far higher than the existing growth rate of 60 mu m/h, so that the high thickness of the P-pressure-resistant layer is realized, and in addition, the defect generation can be reduced by improving the pressure of the reaction chamber and also being one of the reasons that the roughness of the P-pressure-resistant layer is 1-2 nm.
In the step (6), after the growth is completed, the growth gas is cut off, the temperature of the reaction chamber is reduced to 800-900 ℃, the device material is taken out for chemical mechanical polishing treatment, the epitaxial layer with the surface of 1.5-2.5 μm is removed, the roughness is reduced, the surface is smooth and normal, and meanwhile, the pit-shaped defects on the surface can be processed.
Wherein, in the step (7), the temperature of the reaction chamber is firstly increased to 1500-2H4And SiHCl3The flow rates of the components are respectively 14-18ccm/min and 30-50ccm/min, and Al (CH)3)3The flow rate is 50-68 ccm/min; after the growth is finished, keeping hydrogen to be introduced, cutting off other gases, and slowly cooling the reaction chamber to below 1400 ℃. The invention slowly cools the reaction chamber to below 1400 ℃, similar to annealing treatment, releases the stress on the surface of the device material as much as possible, and avoids the adverse effect of the stress on the performance stability of the device. The rate of temperature reduction can be set to, but is not limited to, 10-15 deg.C/min.
In the step (8), after the temperature of the reaction chamber is reduced to 900 ℃, the slice is taken.
The invention has the beneficial effects that:
1. according to the invention, the thickness of the P-voltage-resistant layer is increased, and the design thickness is more than 250 μm, so that the P-channel SiC-IGBT device material can bear 25kV voltage which is far higher than the 15kV voltage-resistant value of the existing common P-channel IGBT device material.
2. The invention adopts the chemical vapor deposition method and controls the silicon-carbon ratio and the doping concentration of each material layer to obtain the high-quality thick epitaxial material with the thickness close to 250 mu m, and the thick epitaxial material has the following advantages besides high pressure resistance value: the saturation current of the device material is larger and reaches 230A/cm2Is much higher than the prior P-channel IGBT material by 200A/cm2Left and right saturated current values; the series resistance of the device material is lower at 18m omega cm2On the other hand, the series resistance of the prior art IBGT device using P-type substrate as N-channel silicon carbide is generally 800-2。
Drawings
FIG. 1 is a schematic structural diagram of an ultrahigh-voltage P-channel SiC-IGBT device material of the invention;
FIG. 2 is a graph comparing scratches before (left in the figure) and after (right in the figure) the treatment of step (2) in example 1;
FIG. 3 is a comparative plot of particulates before (left of figure) and after (right of figure) treatment in step (2) of example 1;
FIG. 4 is a graph showing the results of defect detection of the device material of example 1;
FIG. 5 is a graph showing the results of defect detection of the device material of comparative example 1;
the reference signs are: the device comprises a 1-silicon carbide substrate, a 2-N + buffer layer, a 3-P + buffer layer, a 4-P-voltage-resistant layer and a 5-P-current-collecting layer.
Detailed Description
For the understanding of those skilled in the art, the present invention will be further described with reference to the following examples and accompanying fig. 1-5, which are not intended to limit the present invention.
Example 1
A manufacturing method of an ultrahigh pressure P channel SiC-IGBT device material (shown in figure 1) comprises the following steps:
(1) selecting a silicon carbide substrate 1 and placing the silicon carbide substrate in a reaction chamber;
(2) introducing hydrogen into the reaction chamber, heating the reaction chamber, controlling the pressure of the reaction chamber, introducing HCl gas to perform etching treatment in the heating process of the reaction chamber, and turning off the HCl gas after the temperature is raised to a set value;
(3) depositing an N + buffer layer 2 with the thickness of 1 mu m on a silicon carbide substrate 1 by adopting a chemical vapor deposition method, wherein the growth gas is C2H4And SiHCl3Doping source gas is N2The silicon-carbon ratio was controlled to 0.95 and the doping concentration was controlled to 2 x 10 by setting the gas flow rates of the growth gas and the doping source to18cm-3；
(4) Depositing a P + buffer layer 3 with a thickness of 2 μm on the N + buffer layer 2 by chemical vapor deposition with a growth gas of C2H4And SiHCl3The dopant source gas is Al (CH)3)3The silicon-carbon ratio was controlled to 1.05 and the doping concentration to 2 x 10 by setting the gas flow rates of the growth gas and the doping source to17cm-3；；
(5) Depositing a P-pressure-resistant layer 4 with the thickness of 250 mu m and the roughness of 1.5nm on the P + buffer layer 3 by adopting a chemical vapor deposition method, wherein the growth gas is C2H4And SiHCl3The dopant source gas is Al (CH)3)3The silicon-carbon ratio was controlled to 1.41 and the doping concentration was controlled to 3.0 x 10 by setting the gas flow rates of the growth gas and the doping source to14cm-3；
(6) After the growth is finished, the growth gas is cut off, the device material is taken out for chemical mechanical polishing treatment, then the device material is placed in a reaction chamber, and the step (2) is repeated;
(7) depositing a P-collector layer 5 on the P-voltage-resistant layer 4 by chemical vapor deposition, wherein the growth gas is C2H4And SiHCl3The dopant source gas is Al (CH)3)3The silicon-carbon ratio was controlled to 1.05 and the doping concentration to 8 x 10 by setting the gas flow rates of the growth gas and the doping source to15cm-3Annealing treatment is carried out after growth is finished;
(8) and after the temperature of the reaction chamber is reduced to a set value, taking the plate to obtain the ultrahigh pressure P channel SiC-IGBT device material.
In the step (1), a 6-inch N-type silicon carbide substrate 1 biased toward the <11-20> direction by 4 degrees is selected.
In the step (2), the introduced hydrogen flow is 140L/min, the pressure of the reaction chamber is controlled to be less than 80mbar, then the temperature of the reaction chamber is raised to 1400 ℃, HCl gas is introduced according to the flow of 7.5ccm/min, the temperature is continuously raised to 1700 ℃, and the HCl gas is cut off.
As shown in fig. 2 and 3, after the HCl gas etching treatment, the scratches and the particles of the epitaxial layer were significantly less, and the particles were reduced from 139/wafer to 66/wafer, indicating that the HCl gas etching could effectively remove the scratches and particles.
Wherein, in the step (3), the temperature of the reaction chamber is maintained at 1700 ℃ firstly, and then growth gas and doping source gas, C, are introduced2H4And SiHCl3The flow rates of the two are respectively 8.5ccm/min and 22.5ccm/min, N2The flow rate is 140 ccm/min; after the growth is finished, keeping hydrogen to be introduced, cutting off other gases, and performing pressure-temperature cycle for 2 times, wherein the pressure-temperature cycle is operated as follows: the pressure in the reaction chamber was increased to 550mbar and the temperature was decreased to 1400 ℃, and then the pressure in the reaction chamber was decreased to 80mbar and the temperature was increased to 1700 ℃.
Wherein, in the step (4), the temperature of the reaction chamber is maintained at 1700 ℃ and the pressure is maintained at 80mbar, and then the growth gas and the doping source gas, C, are introduced2H4And SiHCl3The flow rates of (A) and (B) are respectively 16ccm/min and 40ccm/min, Al (CH)3)3The flow rate is 175 ccm/min; keeping hydrogen gas, turning off other gases, keeping for 2min, and introducing C of 7ccm/min2H4And C is turned off after maintaining for 10s2H4。
In the step (5), the temperature of the reaction chamber is firstly reduced to 1535 ℃, the pressure is increased to 135mbar, and then growth gas and doping source gas are introduced, the growth gas C2H4The flow rate of the gas is slowly increased from 16ccm/min to 250ccm/min, and the growth gasBulk SiHCl3The flow rate of (A) is slowly increased from 40ccm/min to 405ccm/min, and Al (CH)3)3The flow rate is 20 ccm/min. The lift rate of the growth gas was 2.0 ccm/s.
In the step (6), after the growth is completed, the growth gas is cut off, and the temperature of the reaction chamber is reduced to 850 ℃.
Wherein, in the step (7), the temperature of the reaction chamber is firstly increased to 1535 ℃, the pressure is controlled to 80mbar, and then the growth gas and the doping source gas, C, are introduced2H4And SiHCl3The flow rates of (A) and (B) are respectively 16ccm/min and 40ccm/min, Al (CH)3)3The flow rate is 59 ccm/min; after the growth is finished, keeping hydrogen to be introduced, cutting off other gases, and slowly cooling the reaction chamber to 1400 ℃ at the cooling rate of 12.5 ℃/min.
In the step (8), after the temperature of the reaction chamber is reduced to 900 ℃, the epitaxial material is taken out and subjected to defect detection, and the detection result is shown in fig. 4.
After the epitaxial material is manufactured into an IGBT device, the withstand voltage value, the saturation current and the series resistance are respectively 28kV, 240A/cm2 and 16 omega-cm measured through performance tests2。
Comparative example 1
This comparative example differs from example 1 in that:
introducing hydrogen into the reaction chamber, controlling the pressure of the reaction chamber, and heating to 1600 ℃ for etching treatment for 10 min; etching by using hydrogen only;
step (3) does not carry out pressure and temperature circulating operation;
after the growth in the step (4) is finished, no ethylene is introduced to fill up the small pit-shaped defects on the epitaxial layer;
in the step (5), the temperature is set to be 1600-;
step (6) does not carry out chemical mechanical polishing treatment;
and (4) annealing treatment is not carried out after the growth in the step (7) is finished.
The defect detection was performed on the epitaxial material under the same conditions as in example 1, and the detection results are shown in FIG. 5.
As shown in fig. 4 and 5, the number of defects in the epitaxial layer grown after HCl gas etching is less, which indicates that HCl gas etching is more favorable for improving the quality of the epitaxial layer than pure hydrogen etching; furthermore, by recording the number of different defects of fig. 4 and 5, the following statistical table is obtained:
| defect of | After optimization | Before optimization |
| Particle/Particle | 9 | 2 |
| Carrot/person | 0 | 25 |
| Triangle/one | 10 | 32 |
| total/number | 19 | 59 |
| defect density number/cm2 | 0.27 | 0.84 |
It can be seen that the epitaxial layer grown after the HCl gas etching has a significant decrease in Carrot (Carrot defect), Triangle defect), total (total number of defects) and defect density, and although the number of particles (small particles on the surface) increases, the particles are taken out after the material growth and have a probability of falling some fine particles on the surface in the air, and some of the particles can be removed by cleaning, which is not fatal defects, and does not affect the device performance, and is mainly related to the cleanliness of the surrounding environment.
Example 2
A manufacturing method of an ultrahigh pressure P channel SiC-IGBT device material (shown in figure 1) comprises the following steps:
(1) selecting a silicon carbide substrate 1 and placing the silicon carbide substrate in a reaction chamber;
(2) introducing hydrogen into the reaction chamber, heating the reaction chamber, controlling the pressure of the reaction chamber, introducing HCl gas to perform etching treatment in the heating process of the reaction chamber, and turning off the HCl gas after the temperature is raised to a set value;
(3) depositing a buffer layer 2 with the thickness of 1.1 mu m N + on the silicon carbide substrate 1 by adopting a chemical vapor deposition method, wherein the growth gas is C2H4And SiHCl3Doping source gas is N2The silicon-carbon ratio was controlled to 0.9 and the doping concentration was controlled to 1.5 x 10 by setting the gas flow rates of the growth gas and the doping source to18cm-3；
(4) Depositing a P + buffer layer 3 with a thickness of 1.8 μm on the N + buffer layer 2 by chemical vapor deposition with a growth gas of C2H4And SiHCl3The doping source gas is Al (CH)3)3The silicon-carbon ratio was controlled to 1.0 and the doping concentration to 1.5 x 10 by setting the gas flow rates of the growth gas and the doping source to17cm-3；
(5) Depositing a P-pressure-resistant layer 4 with the thickness of 255 mu m and the roughness of 1nm on the P + buffer layer 3 by adopting a chemical vapor deposition method, wherein the growth gas is C2H4And SiHCl3The dopant source gas is Al (CH)3)3By setting growth gasAnd the gas flow of the doping source controls the silicon-carbon ratio to be 1.32 and the doping concentration to be 4 x 1014cm-3；
(6) After the growth is finished, the growth gas is cut off, the device material is taken out for chemical mechanical polishing treatment, then the device material is placed in a reaction chamber, and the step (2) is repeated; the polishing treatment can remove pit-shaped defects on the surface, reduce the roughness and facilitate the deposition of the P-collector layer 5;
(7) depositing a P-collector layer 5 on the P-voltage-resistant layer 4 by chemical vapor deposition, wherein the growth gas is C2H4And SiHCl3The dopant source gas is Al (CH)3)3The silicon-carbon ratio was controlled to 1.0 and the doping concentration to 7.5 x 10 by setting the gas flow rates of the growth gas and the doping source to15cm-3Annealing treatment is carried out after growth is finished;
(8) and after the temperature of the reaction chamber is reduced to a set value, taking the plate to obtain the ultrahigh pressure P channel SiC-IGBT device material.
In the step (1), the selected silicon carbide substrate 1 is a 5-inch N-type silicon carbide substrate 1 biased to the <11-20> direction by 3 °.
In the step (2), the introduced hydrogen flow is 130L/min, the pressure of the reaction chamber is controlled to be 75mbar, then the temperature of the reaction chamber is raised to 1500 ℃, HCl gas is introduced according to the flow of 5ccm/min, the temperature is continuously raised to 1750 ℃, and the HCl gas is cut off.
In the step (3), the temperature of the reaction chamber is maintained at 1750 ℃ firstly, and then growth gas and doping source gas C are introduced2H4And SiHCl3The flow rates of the two are respectively 7ccm/min and 20ccm/min, N2The flow rate is 120 ccm/min; after the growth is finished, keeping hydrogen to be introduced, shutting off other gases, and performing pressure-temperature circulation for 2 times, wherein the pressure-temperature circulation is performed by: the pressure in the reaction chamber was increased to 400mbar and the temperature was decreased to 1500 ℃, and then the pressure in the reaction chamber was decreased to 75mbar and the temperature was increased to 1750 ℃.
Wherein, in the step (4), the temperature of the reaction chamber is firstly maintained at 1750 ℃, the pressure is maintained at 75mbar, and then growth gas and doping are introducedSource gas, C2H4And SiHCl3The flow rates of (A) and (B) are respectively 14ccm/min and 30ccm/min, Al (CH)3)3The flow rate is 150 ccm/min; keeping hydrogen gas introduction, cutting off other gas, keeping for 1.5min, and introducing C of 6ccm/min2H4And is kept for 12s and then is turned off2H4。
In the step (5), the temperature of the reaction chamber is firstly reduced to 1500 ℃, the pressure is increased to 140mbar, and then growth gas and doping source gas are introduced, wherein the growth gas C2H4The flow rate of the growth gas is slowly increased to 220ccm/min from 14ccm/min, and SiHCl is grown3The flow rate of (A) is slowly increased from 30ccm/min to 490ccm/min, Al (CH)3)3The flow rate was 15 ccm/min. The lift rate of the growth gas was 1.6 ccm/s.
In the step (6), after the growth is finished, the growth gas is cut off, the temperature of the reaction chamber is reduced to 800 ℃, the device material is taken out for chemical mechanical polishing treatment, an epitaxial layer with the surface of 1.5 mu m is removed, the roughness is reduced, the surface is smooth and normal, and meanwhile, pit-shaped defects on the surface can be treated
In the step (7), the temperature of the reaction chamber is firstly increased to 1500 ℃, the pressure is controlled to 75mbar, and then growth gas and doping source gas, C, are introduced2H4And SiHCl3The flow rates of (A) and (B) are respectively 14ccm/min and 30ccm/min, Al (CH)3)3The flow rate is 50 ccm/min; after the growth is finished, keeping hydrogen to be introduced, cutting off other gases, and slowly cooling the reaction chamber to 1300 ℃ at a cooling rate of 15 ℃/min.
In the step (8), after the temperature of the reaction chamber is reduced to 800 ℃, the slice is taken.
After the epitaxial material is manufactured into an IGBT device, the withstand voltage value, the saturation current and the series resistance are respectively 26kV, 232A/cm2 and 18 omega cm through performance tests2。
Example 3
A manufacturing method of an ultrahigh pressure P channel SiC-IGBT device material (shown in figure 1) comprises the following steps:
(1) selecting a silicon carbide substrate 1 and placing the silicon carbide substrate in a reaction chamber;
(2) introducing hydrogen into the reaction chamber, heating the reaction chamber, controlling the pressure of the reaction chamber, introducing HCl gas to perform etching treatment in the heating process of the reaction chamber, and turning off the HCl gas after the temperature is raised to a set value;
(3) depositing a buffer layer 2 with the thickness of 1.2 mu m N + on the silicon carbide substrate 1 by adopting a chemical vapor deposition method, wherein the growth gas is C2H4And SiHCl3Doping source gas is N2The silicon-carbon ratio was controlled to 1.01 and the doping concentration was controlled to 2.5 x 10 by setting the gas flow rates of the growth gas and the doping source18cm-3；
(4) Depositing a P + buffer layer 3 with a thickness of 2.2 μm on the N + buffer layer 2 by chemical vapor deposition with a growth gas of C2H4And SiHCl3The dopant source gas is Al (CH)3)3The silicon-carbon ratio was controlled to 1.1 and the doping concentration was controlled to 2.5 x 10 by setting the gas flow rates of the growth gas and the doping source to17cm-3；
(5) Depositing a P-pressure-resistant layer 4 with the thickness of 260 mu m and the roughness of 2nm on the P + buffer layer 3 by adopting a chemical vapor deposition method, wherein the growth gas is C2H4And SiHCl3The dopant source gas is Al (CH)3)3The silicon-carbon ratio was controlled to 1.50 and the doping concentration was controlled to 5 x 10 by setting the gas flow rates of the growth gas and the doping source to14cm-3；
(6) After the growth is finished, the growth gas is cut off, the device material is taken out for chemical mechanical polishing treatment, then the device material is placed in a reaction chamber, and the step (2) is repeated;
(7) depositing a P-collector layer 5 on the P-voltage-resistant layer 4 by chemical vapor deposition, wherein the growth gas is C2H4And SiHCl3The dopant source gas is Al (CH)3)3The silicon-carbon ratio was controlled to 1.1 and the doping concentration to 8.5 x 10 by setting the gas flow rates of the growth gas and the doping source to15cm-3Annealing treatment is carried out after growth is finished;
(8) and after the temperature of the reaction chamber is reduced to a set value, taking the plate to obtain the ultrahigh pressure P channel SiC-IGBT device material.
In the step (1), the selected silicon carbide substrate 1 is a 5-inch N-type silicon carbide substrate 1 biased to the <11-20> direction by 3 °.
In the step (2), the introduced hydrogen flow is 150L/min, the pressure of the reaction chamber is controlled to be 70mbar, then the temperature of the reaction chamber is raised to 1450 ℃, HCl gas is introduced according to the flow of 10ccm/min, the temperature is continuously raised to above 1750 ℃, and the HCl gas is cut off.
In the step (3), the temperature of the reaction chamber is maintained at 1750 ℃ firstly, and then growth gas and doping source gas C are introduced2H4And SiHCl3The flow rates of the two are respectively 10ccm/min and 25ccm/min, N2The flow rate is 160 ccm/min; after the growth is finished, keeping hydrogen to be introduced, shutting off other gases, and performing pressure-temperature circulation for 2 times, wherein the pressure-temperature circulation is performed by: the pressure in the reaction chamber was increased to 700mbar and the temperature was decreased to 1300 ℃, then the pressure in the reaction chamber was decreased to 70mbar and the temperature was increased to 1750 ℃.
In the step (4), the temperature of the reaction chamber is maintained at 1750 ℃ and the pressure is maintained at 70mbar, and then growth gas and doping source gas, C, are introduced2H4And SiHCl3The flow rates of (A) and (B) are respectively 18ccm/min and 50ccm/min, Al (CH)3)3The flow rate is 200 ccm/min; keeping hydrogen gas introduction, cutting off other gas, keeping for 2.5min, and introducing C of 8ccm/min2H4And is kept for 8s and then is turned off2H4。
In the step (5), the temperature of the reaction chamber is firstly reduced to 1570 ℃, the pressure is increased to 130mbar, and then growth gas and doping source gas are introduced, wherein the growth gas C2H4The flow rate of the growth gas is slowly increased from 18ccm/min to 280ccm/min, and SiHCl is grown3The flow rate of (A) is slowly increased from 50ccm/min to 520ccm/min, and Al (CH)3)3The flow rate was 78 ccm/min. The lift rate of the growth gas was 2.3 ccm/s.
In the step (6), after the growth is finished, the growth gas is cut off, the temperature of the reaction chamber is reduced to 900 ℃, the device material is taken out for chemical mechanical polishing treatment, and the epitaxial layer with the surface of 2.5 mu m is removed
In the step (7), the temperature of the reaction chamber is firstly increased to 1570 ℃, the pressure is controlled to 75mbar, and then growth gas and doping source gas, C, are introduced2H4And SiHCl3The flow rates of (A) and (B) are respectively 18ccm/min and 50ccm/min, Al (CH)3)3The flow rate is 68 ccm/min; after the growth is finished, keeping hydrogen to be introduced, cutting off other gases, slowly cooling the reaction chamber to 1350 ℃, wherein the cooling rate is 10 ℃/min.
In the step (8), after the temperature of the reaction chamber is reduced to 850 ℃, the slice is taken.
After the epitaxial material is manufactured into an IGBT device, the withstand voltage value, the saturation current and the series resistance are respectively 25kV, 230A/cm2 and 19 omega cm through performance tests2。
Example 4
A manufacturing method of an ultrahigh pressure P channel SiC-IGBT device material (shown in figure 1) comprises the following steps:
(1) selecting a silicon carbide substrate 1 and placing the silicon carbide substrate in a reaction chamber;
(2) introducing hydrogen into the reaction chamber, heating the reaction chamber, controlling the pressure of the reaction chamber, introducing HCl gas to perform etching treatment in the heating process of the reaction chamber, and turning off the HCl gas after the temperature is raised to a set value;
(3) depositing an N + buffer layer 2 with the thickness of 1.5 mu m on a silicon carbide substrate 1 by adopting a chemical vapor deposition method, wherein the growth gas is C2H4And SiHCl3Doping source gas is N2The silicon-carbon ratio was controlled to 0.97 and the doping concentration to 2.2 x 10 by setting the gas flow rates of the growth gas and the doping source to18cm-3；
(4) Depositing a P + buffer layer 3 with a thickness of 2 μm on the N + buffer layer 2 by chemical vapor deposition with a growth gas of C2H4And SiHCl3The dopant source gas is Al (CH)3)3The silicon-carbon ratio was controlled to be 1.03 and the doping concentration to be 1.8 x 10 by setting the gas flow rates of the growth gas and the doping source to be 1.0317cm-3；
(5) Depositing a P-pressure-resistant layer 4 with the thickness of 250 mu m and the roughness of 1.8nm on the P + buffer layer 3 by adopting a chemical vapor deposition method, wherein the growth gas is C2H4And SiHCl3The doping source gas is Al (CH)3)3The silicon-carbon ratio was controlled to 1.4 and the doping concentration to 4.7 x 10 by setting the gas flow rates of the growth gas and the doping source to be equal14cm-3；
(6) After the growth is finished, the growth gas is cut off, the device material is taken out for chemical mechanical polishing treatment, then the device material is placed in a reaction chamber, and the step (2) is repeated;
(7) depositing a P-collector layer 5 on the P-voltage-resistant layer 4 by chemical vapor deposition, wherein the growth gas is C2H4And SiHCl3The dopant source gas is Al (CH)3)3The silicon-carbon ratio was controlled to be 1.08 and the doping concentration to be 8.3 x 10 by setting the gas flow rates of the growth gas and the doping source15cm-3Annealing treatment is carried out after growth is finished;
(8) and after the temperature of the reaction chamber is reduced to a set value, taking the plate to obtain the ultrahigh pressure P channel SiC-IGBT device material.
Wherein, in the step (1), an N-type silicon carbide substrate 1 with 8 inches deviation towards the <11-20> direction by 5 degrees is selected
In the step (2), the flow rate of introduced hydrogen is 145L/min, the pressure of the reaction chamber is controlled to be 70mbar, then the temperature of the reaction chamber is raised to 1400 ℃, HCl gas is introduced according to the flow rate of 8ccm/min, the temperature is continuously raised to 1700 ℃, and HCl gas is shut off.
Wherein, in the step (3), the temperature of the reaction chamber is maintained at 1700 ℃ firstly, and then growth gas and doping source gas, C, are introduced2H4And SiHCl3The flow rates of the two are respectively 9ccm/min and 24ccm/min, N2The flow rate is 130 ccm/min; after the growth is finished, keeping hydrogen to be introduced, shutting off other gases, and performing pressure-temperature circulation for 2 times, wherein the pressure-temperature circulation is performed by: the pressure in the reaction chamber was increased to 600mbar and the temperature was decreased to 1350 deg.c, then the pressure in the reaction chamber was decreased to 70mbar and the temperature was increased to 1700 deg.c.Through the cooling that steps up repeatedly, reduce the adsorption affinity of particulate matter on the epitaxial layer, do benefit to sweeping of carrier gas hydrogen clean, the tiny particulate matter that falls on the buffer layer when showing the reduction growth avoids the particulate matter can form the defect in growth that follows.
Wherein, in the step (4), the temperature of the reaction chamber is maintained at 1700 ℃ at 70mbar, and then the growth gas and the doping source gas, C, are introduced2H4And SiHCl3The flow rates of (A) and (B) are respectively 17ccm/min and 45ccm/min, Al (CH)3)3The flow rate is 160 ccm/min; keeping hydrogen gas, turning off other gases, keeping for 2min, and introducing C of 7.5ccm/min2H4And is kept for 10s and then is turned off2H4。
In the step (5), the temperature of the reaction chamber is firstly reduced to 1550 ℃, the pressure is increased to 140mbar, and then growth gas and doping source gas are introduced, wherein the growth gas C2H4The flow rate of the growth gas is slowly increased from 17ccm/min to 270ccm/min, and SiHCl is grown3The flow rate of (A) is slowly increased from 45ccm/min to 510ccm/min, and Al (CH)3)3The flow rate was 17 ccm/min. The lift rate of the growth gas was 2.1 ccm/s.
In the step (6), after the growth is finished, the growth gas is cut off, the temperature of the reaction chamber is reduced to 85 ℃, the device material is taken out for chemical mechanical polishing treatment, the epitaxial layer with the surface of 2 microns is removed, the roughness is reduced, the surface is smooth and normal, and meanwhile, the pit-shaped defects on the surface can be treated
In the step (7), the temperature of the reaction chamber is firstly increased to 1560 ℃, the pressure is controlled to 70mbar, and then growth gas and doping source gas, C, are introduced2H4And SiHCl3The flow rates of (A) and (B) are respectively 17ccm/min and 45ccm/min, Al (CH)3)3The flow rate is 64 ccm/min; after the growth is finished, keeping hydrogen gas to be introduced, cutting off other gases, and slowly cooling the reaction chamber to 1400 ℃ at the cooling rate of 14 ℃/min.
In the step (8), after the temperature of the reaction chamber is reduced to 900 ℃, the slice is taken.
After the epitaxial material is manufactured into an IGBT device, the withstand voltage value, the saturation current and the series resistance are respectively 24kV, 226A/cm2 and 18 omega-cm through performance tests2。
Example 5
A manufacturing method of an ultrahigh pressure P channel SiC-IGBT device material (shown in figure 1) comprises the following steps:
(1) selecting a silicon carbide substrate 1 and placing the silicon carbide substrate in a reaction chamber;
(2) introducing hydrogen into the reaction chamber, heating the reaction chamber, controlling the pressure of the reaction chamber, introducing HCl gas to perform etching treatment in the heating process of the reaction chamber, and turning off the HCl gas after the temperature is raised to a set value;
(3) depositing an N + buffer layer 2 with a thickness of more than 1.3 μm on a silicon carbide substrate 1 by Chemical Vapor Deposition (CVD) with a growth gas of C2H4And SiHCl3Doping source gas is N2The silicon-carbon ratio was controlled to 0.92 and the doping concentration to 1.7 x 10 by setting the gas flow rates of the growth gas and the doping source to be equal18cm-3；
(4) Depositing a P + buffer layer 3 with a thickness of 2.1 μm on the N + buffer layer 2 by chemical vapor deposition with a growth gas of C2H4And SiHCl3The dopant source gas is Al (CH)3)3The silicon-carbon ratio was controlled to 1.02 and the doping concentration to 1.8 x 10 by setting the gas flow rates of the growth gas and the doping source to17cm-3；
(5) Depositing a P-pressure-resistant layer 4 with the thickness of 250 mu m and the roughness of 1.4nm on the P + buffer layer 3 by adopting a chemical vapor deposition method, wherein the growth gas is C2H4And SiHCl3The dopant source gas is Al (CH)3)3The silicon-carbon ratio was controlled to 1.35 and the doping concentration to 4.2 x 10 by setting the gas flow rates of the growth gas and the doping source to14cm-3；
(6) After the growth is finished, the growth gas is cut off, the device material is taken out for chemical mechanical polishing treatment, then the device material is placed in a reaction chamber, and the step (2) is repeated;
(7) depositing on the P-voltage-resisting layer 4 by chemical vapor depositionA P-collector layer 5 is deposited, and the growth gas is C2H4And SiHCl3The dopant source gas is Al (CH)3)3The silicon-carbon ratio was controlled to be 1.02 and the doping concentration to be 7.8 x 10 by setting the gas flow rates of the growth gas and the doping source to be15cm-3Annealing treatment is carried out after growth is finished;
(8) and after the temperature of the reaction chamber is reduced to a set value, taking the plate to obtain the ultrahigh pressure P channel SiC-IGBT device material.
Wherein, in the step (1), a 4-inch N-type silicon carbide substrate 1 with 2 degrees deviation towards the <11-20> direction is selected
In the step (2), the introduced hydrogen flow is 135L/min, the pressure of the reaction chamber is controlled to be 80mbar, then the temperature of the reaction chamber is increased to be above 1400 ℃, HCl gas is introduced according to the flow of 6.5ccm/min, the temperature is continuously increased to be 1700 ℃, and the HCl gas is cut off.
Wherein, in the step (3), the temperature of the reaction chamber is maintained at 1700 ℃ firstly, and then growth gas and doping source gas, C, are introduced2H4And SiHCl3The flow rates of the two are respectively 7.5ccm/min and 21ccm/min, N2The flow rate is 150 ccm/min; after the growth is finished, keeping hydrogen to be introduced, shutting off other gases, and performing pressure-temperature circulation for 2 times, wherein the pressure-temperature circulation is performed by: the pressure in the reaction chamber was increased to 600mbar and the temperature was decreased to 1400 ℃, and then the pressure in the reaction chamber was decreased to 80mbar and the temperature was increased to 1700 ℃.
In the step (4), firstly, the temperature of the reaction chamber is maintained at 1700 ℃, the pressure is maintained at 80mbar, and then growth gas and doping source gas, C, are introduced2H4And SiHCl3The flow rates of (A) and (B) are respectively 15ccm/min and 35ccm/min, Al (CH)3)3The flow rate is 190 ccm/min; keeping hydrogen gas, turning off other gases, keeping for 2min, and introducing C of 7ccm/min2H4And is kept for 10s and then is turned off2H4。
Wherein, in the step (5), the temperature of the reaction chamber is firstly reduced to 1520 ℃, the pressure is increased to 133mbar, then growth gas and doping source gas are introduced,growth gas C2H4The flow rate of the growth gas is slowly increased to 2.0ccm/min from 15ccm/min, and SiHCl is grown3The flow rate of (A) is slowly increased from 35ccm/min to 500ccm/min, and Al (CH)3)3The flow rate is 16 ccm/min. The lift rate of the growth gas was 1.8 ccm/s.
In the step (6), after the growth is finished, the growth gas is cut off, the temperature of the reaction chamber is reduced to 810 ℃, the device material is taken out for chemical mechanical polishing treatment, and an epitaxial layer with the surface of 2 mu m is removed
Wherein, in the step (7), the temperature of the reaction chamber is firstly increased to 1520 ℃, the pressure is controlled to 80mbar, and then the growth gas and the doping source gas, C, are introduced2H4And SiHCl3The flow rates of (A) and (B) are respectively 15ccm/min and 35ccm/min, Al (CH)3)3The flow rate is 52 ccm/min; after the growth is finished, keeping hydrogen to be introduced, cutting off other gases, and slowly cooling the reaction chamber to below 1400 ℃. The temperature of the reaction chamber is slowly reduced to below 1400 ℃, and the cooling rate is 11 ℃/min.
In the step (8), after the temperature of the reaction chamber is reduced to 900 ℃, the slice is taken.
After the epitaxial material is manufactured into an IGBT device, the withstand voltage value, the saturation current and the series resistance are respectively 25kV, 224A/cm2 and 20 omega-cm measured through performance tests2。
The above-described embodiments are preferred implementations of the present invention, and the present invention may be implemented in other ways without departing from the spirit of the present invention.
Claims (10)
1. An ultrahigh pressure P channel SiC-IGBT device material is characterized in that: comprises the following material layers which are sequentially stacked from bottom to top:
a silicon carbide substrate;
n + buffer layer with thickness of 0.8-1.2 μm, Si/C ratio of 0.9-1.01, and N as doping gas2Has a doping concentration of (1.5-2.5) × 1018cm-3；
A P + buffer layer;
the thickness of the P-pressure-resistant layer is 250-300 mu m, and the carbon-silicon ratio is between 1.32 and 1.50;
and a P-collector layer.
2. The method for manufacturing the ultrahigh-voltage P-channel SiC-IGBT device material according to claim 1, characterized in that: the method comprises the following steps:
(1) selecting a silicon carbide substrate and placing the silicon carbide substrate in a reaction chamber;
(2) introducing hydrogen into the reaction chamber, heating the reaction chamber, controlling the pressure of the reaction chamber, introducing HCl gas to perform etching treatment in the heating process of the reaction chamber, and turning off the HCl gas after the temperature is raised to a set value;
(3) depositing an N + buffer layer with a thickness of more than 1 μm on the silicon carbide substrate by chemical vapor deposition, wherein the growth gas is C2H4And SiHCl3Doping source gas is N2Controlling the Si/C ratio to 0.9-1.01 and the doping concentration to (1.5-2.5) × 10 by setting the gas flow rates of the growth gas and the doping source18cm-3；
(4) Depositing a P + buffer layer with a thickness of 1.8-2.2 μm on the N + buffer layer by chemical vapor deposition method with growth gas of C2H4And SiHCl3The dopant source gas is Al (CH)3)3Controlling the Si/C ratio to 1.0-1.1 and the doping concentration to (1.5-2.5) × 10 by setting the gas flow rates of the growth gas and the doping source17cm-3；
(5) Depositing a P-pressure-resistant layer with the thickness of 250-300 mu m and the roughness of 1-2nm on the P + buffer layer by adopting a chemical vapor deposition method, wherein the growth gas is C2H4And SiHCl3The doping source gas is Al (CH)3)3Controlling the Si/C ratio to 1.32-1.50 and the doping concentration to be less than 5 x 10 by setting the gas flow rates of the growth gas and the doping source14cm-3；
(6) After the growth is finished, the growth gas is cut off, the device material is taken out for chemical mechanical polishing treatment, then the device material is placed in a reaction chamber, and the step (2) is repeated;
(7) depositing a P-collector layer on the P-voltage-resistant layer by chemical vapor deposition, wherein the growth gas is C2H4And SiHCl3The dopant source gas is Al (CH)3)3Controlling the Si/C ratio to 1.0-1.1 and the doping concentration to (7.5-8.5) × 10 by setting the gas flow rates of the growth gas and the doping source15cm-3Annealing treatment is carried out after growth is finished;
(8) and after the temperature of the reaction chamber is reduced to a set value, taking the plate to obtain the ultrahigh pressure P channel SiC-IGBT device material.
3. The manufacturing method of the ultrahigh-voltage P-channel SiC-IGBT device material according to claim 2, characterized in that: in the step (1), the selected silicon carbide substrate is an N-type silicon carbide substrate which is 4-8 inches and is deflected to the <11-20> direction by 2-5 degrees.
4. The manufacturing method of the ultrahigh-voltage P-channel SiC-IGBT device material according to claim 2, characterized in that: in the step (2), the introduced hydrogen flow is 130-150L/min, the pressure of the reaction chamber is controlled to be less than 80mbar, then the temperature of the reaction chamber is increased to be above 1400 ℃, HCl gas is introduced according to the flow of 5-10ccm/min, the temperature is continuously increased to be above 1700 ℃, and the HCl gas is cut off.
5. The manufacturing method of the ultrahigh-voltage P-channel SiC-IGBT device material according to claim 2, characterized in that: in the step (3), the temperature of the reaction chamber is maintained above 1700 ℃, and then growth gas and doping source gas, C, are introduced2H4And SiHCl3The flow rates of the water-based fuel oil are respectively 7-10ccm/min and 20-25 ccm/min; after the growth is finished, keeping hydrogen to be introduced, shutting off other gases, and performing pressure-temperature circulation for 2 times, wherein the pressure-temperature circulation is performed by: the pressure in the reaction chamber is increased to 400-700mbar, the temperature is reduced to 1300-1500 ℃, and then the pressure in the reaction chamber is reduced to below 80mbar, and the temperature is increased to above 1700 ℃.
6. The manufacturing method of the ultrahigh-voltage P-channel SiC-IGBT device material according to claim 2, characterized in that: in the step (4), the temperature of the reaction chamber is maintained above 1700 ℃ and the pressure is maintained below 80mbar, and then growth gas and doping source gas, C, are introduced2H4And SiHCl3The flow rates of the water-based fuel oil are respectively 14-18ccm/min and 30-50 ccm/min; keeping hydrogen gas introduction, cutting off other gas, keeping for 1.5-2.5min, and introducing C of 6-8ccm/min2H4And is turned off after being maintained for 8-12s2H4。
7. The manufacturing method of the ultrahigh-voltage P-channel SiC-IGBT device material according to claim 2, characterized in that: in the step (5), the temperature of the reaction chamber is first reduced to 1500-2H4The flow rate of the growth gas is slowly increased from 14 to 18ccm/min to 220 + 280ccm/min, and SiHCl is grown3The flow rate of (1) is slowly increased from 30-50ccm/min to 490-520 ccm/min.
8. The manufacturing method of the ultrahigh-voltage P-channel SiC-IGBT device material according to claim 2, characterized in that: in the step (6), after the growth is finished, the growth gas is cut off, the temperature of the reaction chamber is reduced to 800-900 ℃, the device material is taken out for chemical mechanical polishing treatment, and the epitaxial layer with the surface of 1.5-2.5 mu m is removed.
9. The manufacturing method of the ultrahigh voltage P-channel SiC-IGBT device material according to claim 2, characterized in that: in the step (7), the temperature of the reaction chamber is firstly raised to 1500-2H4And SiHCl3The flow rates of the water-based fuel oil are respectively 14-18ccm/min and 30-50 ccm/min; after the growth is finished, keeping hydrogen to be introduced, cutting off other gases, and slowly cooling the reaction chamber to below 1400 ℃.
10. The manufacturing method of the ultrahigh voltage P-channel SiC-IGBT device material according to claim 2, characterized in that: in the step (8), after the temperature of the reaction chamber is reduced to 900 ℃, the slice is taken.
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