CN105355561B - A kind of process for surface preparation of reduction SiC MOS interface state densities - Google Patents
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L29/00—Semiconductor devices specially adapted for rectifying, amplifying, oscillating or switching and having potential barriers; Capacitors or resistors having potential barriers, e.g. a PN-junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
- H01L29/66—Types of semiconductor device ; Multistep manufacturing processes therefor
- H01L29/66007—Multistep manufacturing processes
- H01L29/66075—Multistep manufacturing processes of devices having semiconductor bodies comprising group 14 or group 13/15 materials
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- H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
- H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic Table or AIIIBV compounds with or without impurities, e.g. doping materials
- H01L21/30—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26
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Abstract
The present invention relates to performance of semiconductor device technical field of improvement, a kind of process for surface preparation of reduction SiCMOS interface state densities, comprise the following steps：1st, using the cleaning of known RCA methods, drying surface of SiC, 2, using hydrogen nitrogen hybrid plasma the surface of SiC before oxidation is handled, 3, thermal oxide growth SiO2Film, 4, thermal evaporation Al electrodes.The present invention is pre-processed using the low temperature hydrogen nitrogen hybrid plasma of low energy overactivity caused by ECR microwave plasma systems to the surface of SiC before oxidation, not only realize low temperature process, avoid the damage that usual plasma is brought to surface of SiC, and realize the combination of hydrogen and nitrogen passivation effect, effectively remove the foreign ion of surface of SiC and the carbon of residual, the hydrogen and nitrogen on surface inhibit the generation of defect in oxidizing process, significantly reduce SiCMOS interface state densities.In addition, RHEED in-situ monitoring systems are equipped with the system, monitoring and study mechanism especially suitable for surface of SiC state passivating process.
Description
Technical field
The present invention relates to a kind of process for surface preparation of reduction SiC MOS interface state densities, belong to semiconductor devices
Can technical field of improvement.
Background technology
SiC as third generation semi-conducting material, possess compared with Si bigger energy gap, higher electron mobility,
The good characteristics such as saturated electrons speed, thermal conductivity, SiC is set to be more suitable for high temperature, high-power electric and electronic field.Meanwhile SiC is
Unique one kind can form SiO with thermal oxide2The wide bandgap compound semiconductors of film, this feature make SiC-MOS devices use for reference into
Ripe Si techniques are possibly realized.However, due to SiO in actual fabrication2/ SiC interface state densities are too high to cause channel mobility mistake
It is low, the serious performance for restricting SiC-MOS devices.Therefore, SiO is reduced2/ SiC interface state densities are SiC-MOS device research fields
Key technical problem.
At present, SiO is reduced2/ SiC interface state densities focus primarily upon the n2 annealing technique after oxidation.Annealed under NO atmosphere
It is to think to reduce the more significant technique of interface state density, but NO is poisonous, in NFPA (NFPA) health risk
It is number three, it should avoid using as far as possible.AK. saxophone's Le .MK. reaches this [application number：01816726.8] carried in its patent
Go out to use N2High annealing replaces NO to reduce interface state density under O atmosphere.However, either N2O or NO can introduce in interface
Further oxidation occurs for O so that O and N has competitive reaction, finally limits the passivation efficiency of the technique.
Liao Qi pools et al. [application number：201510091817.9] low temperature N is proposed in its patent2/H2Method for annealing reduces boundary
The face density of states.But N2And H2In low temperature it is difficult to resolve into N, H atom, so its actual passivation is N, H molecule, and divide
The N and H of sub- level interface passivation effect are extremely limited.In addition, above method has only been passivated caused in oxidizing process lack
Fall into, passivation effect is extremely limited.
In fact, in addition to caused interfacial state in oxidizing process, characteristic (e.g., C, O pollutant, the absorption of surface of SiC
Thing, dangling bonds, structure etc.) interface will also be impacted.At present, the process of surface treatment on SiC, propose both at home and abroad very
Multi-scheme, wherein mainly have conventional wet processing (such as RCA, boiling water treating, HF/HCL processing), high-temperature hydrogen handle, etc. from
Daughter processing etc..
Being used successfully to clean HF methods, the RCA methods on Si surfaces etc., effectively to remove metal and the organic matter of surface of SiC etc. miscellaneous
Matter, but the pollutant such as surface O, F, C but still has.Boiling water treating method is easy and effective, but its surface easily aoxidizes, and
And it is unstable under the condition of high temperature, post-passivation positive effect decrease is heat-treated more than 400 DEG C.C, OH be present in other surface-And F-From
Sub- adsorption；Use HCl:HF replaces traditional HF:H2Surface ion absorption is advantageously reduced after O to a certain extent, is improved
Hydrogenation effect, but can not fundamentally solve the problems, such as surface state, and the C of remained on surface after cleaning can not be eliminated.
High-temperature hydrogen processing be by the print after cleaning under ultra-pure hydrogen atmosphere high annealing, though with not introducing impurity grain
Son, the features such as hydrogen good passivation effect and surface oxidation-resistant ability are strong, but its treatment temperature is often more than 1000 DEG C, with device
The process compatibility of part is poor.
Radio frequency (RF) H plasma treatment SiC wafer, foreign ion is not introduced though having, the advantages such as treatment temperature is low,
It is due to that radio frequency plasma volume density degree of ionization is low, operation air pressure is high, produces damage to surface and surface reconstructs.
The content of the invention
In order to overcome the deficiencies in the prior art, it is an object of the present invention to provide one kind to reduce SiCMOS interface state densities
Process for surface preparation.The ECR microwave plasma systems that the present invention uses produce the corona treatment SiC of hydrogen nitrogen mixing
Surface, this method can not only effectively Cleaning and Passivation surface of SiC state, and treatment temperature is low, the damage to surface of SiC is small, surface
The hydrogen and nitrogen at place can effectively suppress the formation of defect, improve SiO2Breakdown characteristics, significantly reduce SiCMOS interface state densities.
In order to realize foregoing invention purpose, in the presence of solving the problems, such as prior art, the technical scheme of the invention taken
It is：A kind of process for surface preparation of reduction SiC MOS interface state densities, comprises the following steps：
Step 1, using known RCA methods cleaning, drying surface of SiC；
Step 2, using hydrogen nitrogen hybrid plasma the surface of SiC before oxidation is handled, specifically include following sub-step
Suddenly：
(a) step 1 is cleaned, dry after obtained SiC, be placed in ECR microwave plasma systems under nitrogen protection
In quartz discharge room；
(b) arc chamber is vacuumized, when vacuum reaches 10-4During below Pa, using RHEED observations SiC before treatment
Surface micro-structure；
(c) nitrogen is passed through, flow is controlled in 20~30sccm, is started to carry out heating treatment to SiC under nitrogen protection, is used
In preventing surface of SiC from being polluted by other impurity, temperature control is then turned off Nitrogen source gases at 200~800 DEG C, starts microwave
Source, microwave source Power Control then pass to hydrogen and nitrogen mixture gas in 200~800W, the control of hydrogen flow 40~
80sccm, nitrogen are 1 with hydrogen flow-rate ratio:5~10, now ECR microwave plasma systems produce high concentration, high activity and low
The hydrogen nitrogen hybrid plasma of damage, processing time are controlled in 2-10min；
(d) at interval of 1min using the surface micro-structure after RHEED observation SiC processing, and then determine that treatment effect is optimal
Time point；
(e) after the completion of handling, microwave source and hydrogen source gas are closed, the flow for adjusting nitrogen is controlled in 20~30sccm,
Start to cool under nitrogen protection, SiC is cooled into room temperature takes out；
Step 3, thermal oxide growth SiO2Film, the SiC that sub-step (e) in step 2 is obtained carry out dry-oxygen oxidation processing, tool
Body includes following sub-step：
(a) oxidation furnace is warming up to 1100~1300 DEG C under room temperature condition, furnace air is aoxidized using nitrogen purge,
Under nitrogen protection, SiC substrate is put into quartz boat and is slowly pushed into oxidation furnace pipeline flat-temperature zone, by SiC in pure dry oxygen ambient
90~120min of liner oxidation, form the SiO that a layer thickness is 25~35nm2Film；
(b) after the completion of aoxidizing, keep oxidation furnace temperature-resistant, and nitrogen is passed through into oxidation furnace pipeline, SiC is moved back
Fire processing, annealing time are controlled in 10~30min；
(c) after the completion of annealing, oxidation furnace is cooled to less than 300 DEG C under nitrogen protection, then carry out natural cooling, room temperature
Lower quartz boat of slowly hauling out takes out SiC.
Step 4, thermal evaporation Al electrodes, specifically include following sub-step：
(a) Film by Thermal Oxidation SiO is made in sub-step (c) in step 32The SiC of film, front are protected with photoresist
Firmly, SiC back sides SiO is etched away using the hydrofluoric acid solution of dilution2Film, and remove positive photoresist with acetone soln.
(b) evaporate to form back surface ohmic contacts Al electrodes by impedance heated using metal mask plate, under nitrogen protection
400~450 DEG C are warming up to, anneal 10~30min；
(c) evaporate to form front surface A l gate electrodes by impedance heated using metal mask plate, be warming up under nitrogen protection
400~450 DEG C, anneal 10~30min, is cooled to room temperature and completes SiC mos capacitance element manufacturings.
Present invention has the advantages that：A kind of process for surface preparation of reduction SiCMOS interface state densities, including following step
Suddenly：Step 1, using known RCA methods cleaning, drying surface of SiC, step 2, using hydrogen nitrogen hybrid plasma to oxidation before
Surface of SiC handled, step 3, thermal oxide growth SiO2Film, step 4, thermal evaporation Al electrodes.Compared with the prior art, originally
Invention using low energy overactivity caused by ECR microwave plasma systems low temperature hydrogen nitrogen hybrid plasma to oxidation before
Surface of SiC is pre-processed, and not only realizes low temperature process, avoids the damage that usual plasma is brought to surface of SiC, and
And the combination of hydrogen and nitrogen passivation effect is realized, the ratio of hydrogen and nitrogen is more controllable, effectively removes the foreign ion of surface of SiC
With the carbon of residual, make surface flattening, the hydrogen and nitrogen on surface inhibit the generation of defect in oxidizing process, significantly reduce SiCMOS
Interface state density.In addition, RHEED in-situ monitoring systems are equipped with ECR microwave plasma systems, it is possible to provide surface of SiC is micro-
Structural information, monitoring and study mechanism especially suitable for surface of SiC state passivating process.
Brief description of the drawings
Fig. 1 is the inventive method flow chart of steps.
Fig. 2 is to use surface micro-structure figure of the ECR microwaves hydrogen nitrogen hybrid plasma to SiC before and after the processing.
In figure：(a) it is before processing surface of SiC micro-structural figure.
(b) be processing after 2min surface of SiC micro-structural figure.
(c) be processing after 4min surface of SiC micro-structural figure.
(d) be processing after 6min surface of SiC micro-structural figure.
(e) be processing after 8min surface of SiC micro-structural figure.
(f) be processing after 10min surface of SiC micro-structural figure.
Fig. 3 is SiO2The current density of film-field strength characteristics curve map.
In figure：(a) it is not use the SiO that the inventive method obtains2The current density of film-field strength characteristics curve map.
(b) it is that the SiO obtained after 8min is handled to surface of SiC using the inventive method2The current density of film-field strength is special
Linearity curve figure.
Fig. 4 is distribution map of the SiCMOS interface state densities with energy.
In figure：(a) it is not use distribution map of the SiCMOS interface state densities that the inventive method obtains with energy.
(b) it is that the SiCMOS interface state densities obtained after 8min are handled with energy to surface of SiC using the inventive method
Distribution map.
Embodiment
With reference to embodiment, the invention will be further described.
Embodiment 1
As shown in figure 1, a kind of process for surface preparation of reduction SiCMOS interface state densities, comprises the following steps：
Step 1, using known RCA methods cleaning, drying surface of SiC, specifically include following sub-step：
(a) SiC is put in beaker, using deionized water plus be cleaned by ultrasonic for several times to without obvious foreign matter；
(b) cleaned using the concentrated sulfuric acid, 10min is boiled after being heated to 80 DEG C, then soak 30min, added hydrogen peroxide and soak again
30min, deionized water rinsing surface is several times；
(c) using deionized water, H2O2、NH4OH mixed solutions clean, and are then cleaned again with buffered hydrofluoric acid solution, finally
With deionized water rinsing surface of SiC several times；
(d) using deionized water, H2O2, HCl mixed solutions cleaning, then cleaned with buffered hydrofluoric acid solution, finally used again
Deionized water rinsing surface of SiC is several times；
(e) surface of SiC is dried using infrared lamp.
Step 2, using hydrogen nitrogen hybrid plasma the surface of SiC before oxidation is handled, specifically include following sub-step
Suddenly：
(a) step 1 is cleaned, dry after obtained SiC, be placed in ECR microwave plasma systems under nitrogen protection
In quartz discharge room.
(b) arc chamber is vacuumized, when vacuum reaches 10-4During below Pa, using RHEED observations SiC before treatment
Surface micro-structure.
(c) nitrogen that flow is 20sccm is passed through, starts to carry out heating treatment to SiC under nitrogen protection, for preventing
Surface of SiC is polluted by other impurity, and temperature control is then turned off Nitrogen source gases at 400 DEG C, starts microwave source, microwave source work(
Rate control then passes to hydrogen and nitrogen mixture gas in 650W, and nitrogen and hydrogen flowing quantity are respectively 6sccm, 60sccm, now ECR
Microwave plasma system produces high concentration, high activity and the hydrogen nitrogen of low damage and mixes post plasma, and processing time control exists
8min。
(d) at interval of 1min using the surface micro-structure after RHEED observation SiC processing, and then determine that treatment effect is optimal
Time point.
(e) after the completion of handling, microwave source and hydrogen source gas are closed, flow is passed through and is protected for 25sccm nitrogen and in nitrogen
Under start to cool, by SiC be cooled to room temperature take out.
Step 3, thermal oxide growth SiO2Film, the SiC that sub-step (e) in step 2 is obtained carry out dry-oxygen oxidation processing, tool
Body includes following sub-step：
(a) oxidation furnace is warming up to 1180 DEG C under room temperature condition, furnace air is aoxidized using nitrogen purge, protected in nitrogen
Under shield, the SiC substrate that sub-step (e) in step 2 obtains is put into quartz boat and is slowly pushed into oxidation furnace pipeline flat-temperature zone, pure
SiC substrate is aoxidized into 105min in dry oxygen ambient, forms the SiO that a layer thickness is 34nm2Film.
(b) after the completion of aoxidizing, keep 1180 DEG C of furnace temperature of oxidation constant, and nitrogen is passed through into oxidation furnace pipeline, to SiC
Made annealing treatment, annealing time 30min.
(c) after the completion of annealing, oxidation furnace is cooled to less than 300 DEG C under nitrogen protection, then carry out natural cooling, room temperature
Lower quartz boat of slowly hauling out takes out SiC.
Step 4, thermal evaporation Al electrodes, specifically include following sub-step：
(a) Film by Thermal Oxidation SiO is made in sub-step (c) in step 32The SiC of film, front are protected with photoresist
Firmly, SiC back sides SiO is etched away using the hydrofluoric acid solution (1%) of dilution2Film, and remove positive photoresist with acetone soln.
(b) evaporate to form back surface ohmic contacts Al electrodes by impedance heated using metal mask plate, thickness of electrode is
300nm, electrode pattern are a diameter of 2000 μm of circles, are warming up to 410 DEG C after the completion of evaporation under nitrogen protection, and anneal 30min.
(c) evaporate to form front surface A l gate electrodes by impedance heated using metal mask plate, thickness of electrode 300nm, electricity
Pole figure shape is the circle that diameter is respectively 100,200 and 400 μm, is warming up to 400 DEG C after the completion of evaporation under nitrogen protection, annealing
10min, it is cooled to room temperature and completes SiC mos capacitance element manufacturings.
Embodiment 2
Reference picture 2, the surface of SiC RHEED images although linear striated, but striped cleaned by traditional RCA methods
Unintelligible and poor contrast, illustrate that surface of SiC atomic arrangement is irregular, single-crystal orientation is poor.Post plasma is mixed by hydrogen nitrogen
After processing, as the increase RHEED images of processing time occur gem-pure linear striped in 8min, contrast nor
Chang Gao, illustrate that surface of SiC cleans, atomic arrangement is regular, smooth, single-crystal orientation is good, and mixed by calculating through ECR hydrogen nitrogen
Surface of SiC after corona treatment is approximately 1 × 1 structure, is not reconstructed.
Embodiment 3
8min pretreatments are carried out to surface of SiC with the inventive method using the SiC mos capacitances device that conventional method obtains
Resulting SiC mos capacitance devices afterwards, I-V characteristic test is carried out, it is complete using Keithley4200 Semiconductor Parameter Analyzers
Into voltage scan range 0-38V, voltage step size 0.05V, retention time 0.1s.Measured result as shown in figure 3, using
The SiC mos capacitances device that conventional method obtains with the inventive method contrasts, and obtains SiO2The disruptive field intensity of film is respectively
9.5MV/cm and 10.1MV/cm, barrier height are respectively 2.48eV and 2.74eV, illustrate to use ECR hydrogen nitrogen hybrid plasmas
Processing improves SiO compared with conventional method2The insulation characterisitic of film.
Embodiment 4
The SiC mos capacitances device that is obtained using conventional method with through ECR hydrogen nitrogen hybrid plasmas to the pre- place of surface of SiC
SiC mos capacitance devices obtained by after reason 8min, carry out C-V characteristic tests, utilize the semiconductor parameters point of Keithley 4200
Analyzer and Lake Shore TTPX cold probe platforms are completed, and cryogenic conditions are realized by liquid nitrogen refrigerating, voltage scan range for+
10~-10V, voltage step size 0.02V, retention time 0.1s.Measured result is as shown in figure 4, at hydrogen nitrogen hybrid plasma
After reason, the interface state density of whole SiC forbidden bands top half substantially reduces, and gradually deepens with energy level, and it is gradual that it reduces amplitude
Increase.In EC- E=0.06eV locates, and the processing of hydrogen nitrogen hybrid plasma makes interface state density by the 7.6 × 10 of before processing13cm- 2eV-1It is reduced to 4.7 × 1013cm-2eV-1；In 0.2eV<EC–E<In the range of 0.6eV, SiC after the processing of hydrogen nitrogen hybrid plasma
MOS interface state density reduces amplitude close to an order of magnitude, in EC- E=0.2eV and EC- E=0.6eV locates, interface state density
Respectively by the 6.1 × 10 of before processing12cm-2eV-1With 8.8 × 1011cm-2eV-14.6 × 10 be reduced to after processing12cm-2eV-1With
2.1×1011cm-2eV-1.The SiC forbidden band first halves can effectively be reduced by illustrating the hydrogen nitrogen hybrid plasma processing method of the present invention
The interface state density divided.It is as shown in Table 1 below.
Table 1
The invention has the advantages that：A kind of process for surface preparation, ECR microwaves etc. of reduction SiC MOS interface state densities from
The low temperature hydrogen nitrogen hybrid plasma of low energy overactivity caused by daughter system realizes low temperature process, avoids Conventional plasma
The damage that body is brought to surface of SiC, and the combination of hydrogen and nitrogen passivation effect is realized, surface of SiC defect can be effectively removed,
Make surface flattening, the hydrogen and nitrogen on surface inhibit the generation of defect in oxidizing process, therefore, the oxide-film of SiC MOS devices
Quality significantly improves SiO2/ SiC interface state densities significantly reduce.
Claims (1)
1. a kind of process for surface preparation of reduction SiC MOS interface state densities, it is characterised in that comprise the following steps：
Step 1, using RCA methods cleaning, drying surface of SiC；
Step 2, using hydrogen nitrogen hybrid plasma the surface of SiC before oxidation is handled, specifically include following sub-step：
(a) step 1 is cleaned, dry after obtained SiC, be placed in the quartz of ECR microwave plasma systems under nitrogen protection
In arc chamber；
(b) arc chamber is vacuumized, when vacuum reaches 10-4During below Pa, the surfaces of SiC before treatment are observed using RHEED
Micro-structural；
(c) nitrogen is passed through, flow is controlled in 20~30sccm, starts to carry out heating treatment to SiC under nitrogen protection, for preventing
Only surface of SiC is polluted by other impurity, and temperature control is then turned off Nitrogen source gases at 200~800 DEG C, starts microwave source, micro-
Wave source Power Control then passes to hydrogen and nitrogen mixture gas in 200~800W, and hydrogen flow is controlled in 40~80sccm, nitrogen
It is 1 with hydrogen flow-rate ratio:5~10, now ECR microwave plasma systems generation high concentration, high activity and the hydrogen of low damage
Nitrogen hybrid plasma, processing time are controlled in 2-10min；
(d) at interval of 1min using RHEED observation SiC processing after surface micro-structure, and then determine treatment effect it is optimal when
Between point；
(e) after the completion of handling, microwave source and hydrogen source gas are closed, the flow control of nitrogen is adjusted in 20~30sccm, in nitrogen
Start to cool under protection, SiC is cooled into room temperature takes out；
Step 3, thermal oxide growth SiO2Film, the SiC that sub-step (e) in step 2 is obtained carry out dry-oxygen oxidation processing, specific bag
Include following sub-step：
(a) oxidation furnace is warming up to 1100~1300 DEG C under room temperature condition, furnace air is aoxidized using nitrogen purge, in nitrogen
Under protection, SiC substrate is put into quartz boat and is slowly pushed into oxidation furnace pipeline flat-temperature zone, by SiC substrate in pure dry oxygen ambient
90~120min is aoxidized, forms the SiO that a layer thickness is 25~35nm2Film；
(b) after the completion of aoxidizing, keep oxidation furnace temperature-resistant, and nitrogen is passed through into oxidation furnace pipeline, SiC is carried out at annealing
Reason, annealing time are controlled in 10~30min；
(c) after the completion of annealing, oxidation furnace is cooled to less than 300 DEG C under nitrogen protection, then carries out natural cooling, is delayed at room temperature
Slow quartz boat of hauling out takes out SiC；
Step 4, thermal evaporation Al electrodes, specifically include following sub-step：
(a) Film by Thermal Oxidation SiO is made in sub-step (c) in step 32The SiC of film, front protect with photoresist, use
The hydrofluoric acid solution of dilution etches away SiC back sides SiO2Film, and remove positive photoresist with acetone soln；
(b) evaporate to form back surface ohmic contacts Al electrodes by impedance heated using metal mask plate, heat up under nitrogen protection
To 400~450 DEG C, anneal 10~30min；
(c) evaporate to form front surface A l gate electrodes by impedance heated using metal mask plate, it is warming up to 400 under nitrogen protection~
450 DEG C, anneal 10~30min, is cooled to room temperature and completes SiC mos capacitance element manufacturings.
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| CN108010840B (en) * | 2016-11-02 | 2021-04-23 | 株洲中车时代半导体有限公司 | Method for manufacturing doped semiconductor device and semiconductor device |
| CN108257861B (en) * | 2016-12-28 | 2021-09-21 | 全球能源互联网研究院 | Preparation method of gate oxide layer and MOS power device |
| CN108257859B (en) * | 2016-12-28 | 2021-09-03 | 全球能源互联网研究院 | Preparation method of gate oxide layer and MOSFET power device |
| CN109003895B (en) * | 2018-07-19 | 2021-06-08 | 大连理工大学 | Manufacturing method for improving performance stability of SiC MOSFET device |
| CN109103078A (en) * | 2018-10-03 | 2018-12-28 | 大连理工大学 | A kind of passivating method improving SiC MOSFET element high and low temperature stability |
| CN109524304B (en) * | 2018-11-21 | 2021-04-27 | 北京国联万众半导体科技有限公司 | Method for processing silicon carbide gate dielectric fluorine plasma and silicon carbide power device |
| CN111710599A (en) * | 2020-06-30 | 2020-09-25 | 全球能源互联网研究院有限公司 | Preparation method of silicon carbide ohmic contact |
| CN112820639B (en) * | 2021-01-02 | 2024-05-31 | 大连理工大学 | Improved silicon carbide MOSFET device preparation process |
| CN113889394B (en) * | 2021-09-25 | 2023-03-14 | 大连理工大学 | SiC semiconductor dry surface treatment equipment and method |
| CN115747751A (en) * | 2022-11-15 | 2023-03-07 | 英利能源发展有限公司 | Preparation method of silicon oxide |
| CN115784774B (en) * | 2023-02-06 | 2023-04-25 | 江苏邑文微电子科技有限公司 | Method for improving SiC Mos interface characteristics |
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| CN1552092A (en) * | 2000-10-03 | 2004-12-01 | ���﹫˾ | Method of fabricating an oxide layer on a silicon carbide layer utilizing NO2 |
| CN102629559A (en) * | 2012-04-20 | 2012-08-08 | 西安电子科技大学 | Manufacture method of stacked gate SiC-metal insulator semiconductor (MIS) capacitor |
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