CN106381523A - Vertical hydride gas phase epitaxial growth system - Google Patents

Vertical hydride gas phase epitaxial growth system Download PDF

Info

Publication number
CN106381523A
CN106381523A CN201610810916.2A CN201610810916A CN106381523A CN 106381523 A CN106381523 A CN 106381523A CN 201610810916 A CN201610810916 A CN 201610810916A CN 106381523 A CN106381523 A CN 106381523A
Authority
CN
China
Prior art keywords
gas
cavity
reaction
vertical
phase epitaxy
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN201610810916.2A
Other languages
Chinese (zh)
Inventor
修向前
张�荣
华雪梅
谢自力
陈鹏
刘斌
周玉刚
韩平
施毅
顾书林
胡立群
郑有炓
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Nanjing University
Original Assignee
Nanjing University
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Nanjing University filed Critical Nanjing University
Priority to CN201610810916.2A priority Critical patent/CN106381523A/en
Publication of CN106381523A publication Critical patent/CN106381523A/en
Pending legal-status Critical Current

Links

Classifications

    • CCHEMISTRY; METALLURGY
    • C30CRYSTAL GROWTH
    • C30BSINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
    • C30B29/00Single crystals or homogeneous polycrystalline material with defined structure characterised by the material or by their shape
    • C30B29/10Inorganic compounds or compositions
    • C30B29/40AIIIBV compounds wherein A is B, Al, Ga, In or Tl and B is N, P, As, Sb or Bi
    • C30B29/403AIII-nitrides
    • C30B29/406Gallium nitride
    • CCHEMISTRY; METALLURGY
    • C30CRYSTAL GROWTH
    • C30BSINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
    • C30B25/00Single-crystal growth by chemical reaction of reactive gases, e.g. chemical vapour-deposition growth
    • C30B25/02Epitaxial-layer growth
    • C30B25/10Heating of the reaction chamber or the substrate
    • CCHEMISTRY; METALLURGY
    • C30CRYSTAL GROWTH
    • C30BSINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
    • C30B25/00Single-crystal growth by chemical reaction of reactive gases, e.g. chemical vapour-deposition growth
    • C30B25/02Epitaxial-layer growth
    • C30B25/14Feed and outlet means for the gases; Modifying the flow of the reactive gases

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Inorganic Chemistry (AREA)
  • Crystals, And After-Treatments Of Crystals (AREA)

Abstract

The invention relates to a vertical hydride gas phase epitaxial growth system, which comprises a reaction cavity, a graphite support, an epitaxial growth substrate, a vacuum device and a heating system, wherein the graphite support is arranged in the growth region of the reaction cavity. The vertical hydride gas phase epitaxial growth system is characterized in that the reaction cavity is of a vertical structure; the height of the growth region in the reaction cavity is 1 to 10cm; the reaction cavity consists of a cavity pipe and a plurality of gas catheters; parts, positioned at an upper part inlet of the cavity pipes, of gas catheters of reaction source gas and loaded gas downward extend, and are used for conveying reaction gas to the epitaxial growth substrate position on the graphite support in the growth region; a suck-in opening of the vacuum device is connected with an outlet of the reaction cavity, so that 0.1 to 1 barometric pressure is maintained in the reaction cavity; gas inlet gas catheters of 2 to 3 kinds of reaction source gas in the cavity use non-coaxial structures and are distributed at the two sides of the center axial line of the cavity pipe.

Description

A kind of vertical hydride vapor phase epitaxy growth system
Technical field
The present invention relates to hydride gas-phase epitaxy HVPE growing system, for semi-conducting materials such as growths such as GaN base material, For a kind of vertical hydride vapor phase epitaxy growth system.
Background technology
III-V nitride material (also known as GaN base material) based on GaN and InGaN, AlGaN alloy material is near In the past few years valued novel semiconductor material again in the world.
The growth of GaN base material has a variety of methods, such as gas phase epitaxy of metal organic compound (MOCVD), High Temperature High Pressure synthesis Body GaN single crystal, molecular beam epitaxy (MBE), sublimed method and hydride gas-phase epitaxy (HVPE) etc..Due to GaN base material itself The restriction of physical property, the growth of GaN body monocrystalline has very big difficulty, not yet practical.Hydride gas-phase epitaxy is due to tool There are high rate of growth and laterally-longitudinal extension ratio, can be used for isoepitaxial growth Free-standing GaN substrate, cause and widely pay attention to And research.
The restriction being transported etc. due to traditional horizontal HVPE internal system structure, air-flow, large area (>2 inches) GaN base material The uniformity of growth remains a need for further Improvement.In vertical HVPE growing system, because reaction cavity can be designed to Axisymmetric, the transport system of gas is easier more than horizontal system and evenly, finally grows the material thickness obtaining Evenly.Update vertical HVPE growing system significant for the growth of GaN base material.In vertical HVPE system In, due to the pre-reaction of ammonia and GaCl, meeting blocking pipeline, cause the termination that GaCl reacting gas transports, and hinder reaction Carry out further.The vertical HVPE system of present invention design proposes inventive process for the problems referred to above, due to holding Reforwarding row, in addition to basic application, can be exclusively used in the long-time growth of Centimeter Level large scale GaN body monocrystal material.
Content of the invention
The technical problem to be solved in the present invention is:Improve existing HVPE growing system, high-volume can efficiently produce tool There is the semiconductor film material of excellent homogeneity;Centimeter Level large scale GaN body monocrystal material can be carried out long lasting for operation Growth.
The technical scheme is that:A kind of vertical hydride vapor phase epitaxy growth system, props up including reaction cavity, graphite Support, epitaxial growth substrate, vacuum equipment and heating system, graphite rest is arranged on the vitellarium of reaction cavity, it is characterized in that anti- Cavity is answered to be vertical structure, the high 1~10cm in vitellarium, especially 2~5cm in reaction cavity, reaction cavity is by cavity pipe and many Gas conduit composition, the gas conduit of reaction source gas and supporting gas is located at the upper entrance part of cavity pipe to downward Stretch, for delivering to reacting gas at the epitaxial growth substrate on the graphite rest of vitellarium, the suction inlet of vacuum equipment is reversed Answer cavity one outlet, make to keep 0.1-1 atmospheric pressure in reaction cavity;2-3 kind (main) reaction source gas air inlet in cavity Gas conduit adopts non-coaxial structure distribution in the central axis both sides of cavity pipe, and can be centrosymmetric.
The gas conduit mouth of reaction source gas is less than the gas conduit mouth of supporting gas.
Rotate to ensure the thickness evenness of epitaxial semiconductor material by the epitaxial growth substrate on graphite rest.
Further, different reacting gas passes through different gas conduit conveying, dominant response source gas ammonia and chlorine Change gallium and be transported to above substrate using non-coaxial structure, horizontal plane centrosymmetry mode, (two kinds of main source gas ammonias and GaCl Being distributed in vertical chamber central axle both sides in inside cavity outlet is in horizontal plane centrosymmetry).
Graphite rest rotates around longitudinal center axis, 0~1000 rev/min of rotating speed.
Outlet level interval D of reaction source gas ammonia and gallium chloride gas conduit, D 1-150mm.
Heating system adopts dual temperature area or three-temperature-zone mode, and mode of heating is resistance heating or radio frequency heating;Using radio frequency During heating it is:Reaction cavity is externally provided with graphite bush, and graphite bush is arranged on the induction coil of superaudio electromagnetic induction heater In, graphite sleeve external sheath heat conduction non-flammable insulating barrier, it is placed in inert gas environment.
Further, different reacting gas passes through different gas conduit conveyings.Two kinds of main source gas ammonias and It is in horizontal plane centrosymmetry that GaCl is distributed in vertical chamber central axle both sides in inside cavity outlet, to prevent two kinds of gases mutual Diffusion generates GaN blocking and each exports, and maximum benefit can be prevented from causing in GaCl exit because what reaction in advance caused GaN deposition, block pipeline thus degrowth speed even terminates growing.Using the design of this non-axis symmetry, can increase and hold Continuous growth time, to dozens or even hundreds of hour, may finally make sample grown arrive the thickness of millimeter or even centimetres.
Beneficial effect:Dominant response source proposed by the present invention gas piping nonaxisymmetric structure, can effectively prevent pre- React cause deposition, blocking, improve HVPE system the continued propagation time, obtain naturally do not exist at present, conventional method no The GaN body monocrystal material of method growth.This is main areas of application of the invention.The present invention proposes outside a kind of vertical hydrogenation thing gas phase Prolong the system structure of (HVPE) growth apparatus, to realize on a large scale should of the semiconductor film materials such as GaN base backing material growth With.The growth of the GaN substrate material that the achievable monolithic of the present invention is 6,72.
Brief description
Fig. 1 is the present invention vertical HVPE growing system reaction chamber internal gas transport structure schematic diagram it is shown that reaction chamber The nonaxisymmetric structure of dominant response source gas ammonia and gallium chloride in body.
The analog result of GaN deposition rate distribution in Fig. 2 embodiment, A, B, C, D, E correspond to the different speeds of rotation.This In secondary embodiment, optimal speed of rotation 70-90 rev/min (C, D scheme), is coincide with experimental result.
6 GaN substrate samples and uniformity in Fig. 3 embodiment.
Specific embodiment
Reaction cavity of the present invention is vertical structure, is made up of cavity pipe and branched gas conduit, and gas conduit is located at cavity Pipe entrance part, for reacting gas is delivered at the epitaxial growth substrate of vitellarium, heating system adopt resistance furnace or RF heating. generally dual temperature plot structure, it is divided into metal source and vitellarium.HCl and source metal reaction, generation Gaseous product enters vitellarium, reacts in substrate surface and NH3 mixing, forms GaN.Tail gas and reaction dust pass through pumping System is extracted out.Metal source temperature is from 500-1000 degree Celsius (generally 850-900 degree Celsius of temperature during growth GaN), growth Area's temperature is from 450-1100 degree Celsius (generally 1000-1100 degree Celsius of temperature during growth GaN).The gas of carrier gas conduit of nitrogen It is distributed around.The bottom of cavity pipe is provided with gas discharge outlet outlet, and that is, the bottom of vacuum equipment connection cavity pipe is provided with Gas conduit.
Highly in 10 cm range, substrate maximum gauge is 160mm to vitellarium (axial flat-temperature zone) of the present invention.
The present invention adopts different source metal, gallium, indium, aluminum, magnesium etc., and each source metal has independent gas to lead Pipe conveys.Vitellarium graphite rest horizontal positioned, can rotate around rest centrage, rotating speed, can from 0~1000 rev/min To improve the uniformity of GaN film.Epitaxial growth substrate can just be placed on graphite can also adopt using hang upside down mode Mode on rest, reacting gas air inlet can be in the way of using upwardly or downwardly transporting, with backing material modes of emplacement Different and different.
In cavity, two kinds of main source gases adopt nonaxisymmetric structure, it is to avoid the response speed that mutually pre-reaction causes reduces Even stop.Heating system of the present invention adopts dual temperature area or three-temperature-zone mode, and mode of heating is resistance heating or radio frequency heating.Adopt During with radio frequency heating it is:Reaction cavity is externally provided with graphite bush, and graphite bush is arranged on the sense of superaudio electromagnetic induction heater Answer in coil, graphite sleeve external sheath heat conduction non-flammable insulating barrier, it is placed in inert gas environment.
Reaction cavity of the present invention adopts quartzy tubular construction, as shown in Figure 1.Ammonia and gallium chloride gas outlet adopt non-axle pair Claim structure, horizontal plane centrosymmetry is in axis both sides.Reaction cavity pressure is maintained at 0.1-1 atmospheric pressure.In ammonia and GaCl Between gas, reaction cavity central axis direction adopts carrier gas to separate, anti-to reduce the space that two gas pre-mixed conjunctions cause further Should, this reaction in advance causes source gas phase counterdiffusion, and forms GaN in GaCl line portals deposition, can reduce GaCl and be transported to The concentration of substrate is thus reduce growth rate.Also this mouth of pipe can be blocked in the GaCl long-pending GaN that is fond of salty food, cause on the substrate of vitellarium The termination of GaN growth.Carrier gas adopts nitrogen or argon or hydrogen and hydrogen and nitrogen mixed gas.
The substrate speed of rotation of the present invention is from 0-1000 rev/min.Hydrodynamic analogy research shows, turns in the present embodiment When speed is for 70-90 rev/min, uniform GaN thickness distribution can be obtained.Analog result is as shown in Figure 2.
One of the technology of the present invention embodiment, Sapphire Substrate is just placing growth GaN thick film in vertical HVPE growing system, Reacting gas is transported to above substrate down from above.Including following several steps:
1st, the cleaning of Sapphire Substrate and process.
2nd, after Sapphire Substrate is put in reactor, it is to slowly warm up to growth temperature, you can start to grow GaN.Growth temperature 1000~1100 DEG C of degree.Gas flow is respectively:NH3Flow is 2000sccm, NH3Carrier gas flux is 1000sccm, and HCl flow is 50sccm, HCl carrier gas flux is 500sccm, and total nitrogen is 15000sccm.In this example between ammonia and gallium chloride outlet level Away from for D=100mm.Sample is 2 inches of 6 Sapphire Substrate.1 atmospheric pressure of reaction cavity pressure.
3rd, after growing into the suitable time, it is slowly dropped to room temperature according to certain speed, take out sample.Raw in the present embodiment Long-time about 10 minutes, growth rate was micro- m/h of 120-150, and thickness of sample is 20 microns.Thickness of sample is uniform Property as shown in figure 3, between 6 sample strip thickness difference in the range of 4%, show good thickness evenness.
The main source gas non-axisymmetric distribution structure of gas conduit employing of the present invention simultaneously adopts separate gas and rotation etc., Ensure that vertical HVPE system long lasting for operation, obtain grade large scale GaN body monocrystal material.

Claims (9)

1. a kind of vertical hydride vapor phase epitaxy growth system, is characterized in that including reaction cavity, graphite rest, epitaxial growth lining Bottom, vacuum equipment and heating system, graphite rest is arranged on the vitellarium of reaction cavity, it is characterized in that reaction cavity is vertical knot Structure, height 1~10cm in vitellarium in reaction cavity, reaction cavity is made up of cavity pipe and branched gas conduit, reaction source gas The upper entrance part being located at cavity pipe with the gas conduit of supporting gas extends downwardly, for reacting gas is delivered to vitellarium Graphite rest on epitaxial growth substrate at, the suction inlet of vacuum equipment connects reaction cavity one outlet, makes in reaction cavity Keep 0.1-1 atmospheric pressure;In cavity, 2-3 kind reaction source gas air inlet gas conduit adopts non-coaxial structure distribution in cavity pipe Central axis both sides.
2. vertical hydride vapor phase epitaxy growth system according to claim 1, is characterized in that reaction source gas gas is led The mouth of pipe is less than the gas conduit mouth of supporting gas.
3. vertical hydride vapor phase epitaxy growth system according to claim 1, is characterized in that by graphite rest Epitaxial growth substrate rotates and to ensure the thickness evenness of epitaxial semiconductor material.
4. vertical hydride vapor phase epitaxy growth system according to claim 1, is characterized in that different reacting gas lead to Cross different gas conduit conveyings, dominant response source gas ammonia and gallium chloride adopt non-coaxial structure, horizontal plane centrosymmetry Mode is transported to above substrate.
5. vertical hydride vapor phase epitaxy growth system according to claim 1, is characterized in that graphite rest in longitudinal direction Heart axis rotates, 0~1000 rev/min of rotating speed.
6. vertical hydride vapor phase epitaxy growth system according to claim 1, it is characterized in that reaction source gas ammonia and Outlet level interval D of gallium chloride gas conduit, D takes 1-150mm.
7. vertical hydride vapor phase epitaxy growth system according to claim 1, is characterized in that heating system adopts dual temperature Area or three-temperature-zone mode, mode of heating is resistance heating or radio frequency heating;During using radio frequency heating it is:Reaction cavity is externally provided with stone Black sleeve pipe, graphite bush is arranged in the induction coil of superaudio electromagnetic induction heater, and graphite sleeve external sheath heat conduction is non- Inflammable insulating barrier, is placed in inert gas environment.
8. vertical hydride vapor phase epitaxy growth system according to claim 1, is characterized in that the bottom of cavity pipe is provided with Gas discharge outlet outlet, the gas conduit that is, bottom of vacuum equipment connection cavity pipe is provided with.
9. vertical hydride vapor phase epitaxy growth system according to claim 1, is characterized in that vitellarium height 2~5cm.
CN201610810916.2A 2016-09-08 2016-09-08 Vertical hydride gas phase epitaxial growth system Pending CN106381523A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201610810916.2A CN106381523A (en) 2016-09-08 2016-09-08 Vertical hydride gas phase epitaxial growth system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201610810916.2A CN106381523A (en) 2016-09-08 2016-09-08 Vertical hydride gas phase epitaxial growth system

Publications (1)

Publication Number Publication Date
CN106381523A true CN106381523A (en) 2017-02-08

Family

ID=57935433

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201610810916.2A Pending CN106381523A (en) 2016-09-08 2016-09-08 Vertical hydride gas phase epitaxial growth system

Country Status (1)

Country Link
CN (1) CN106381523A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114197037A (en) * 2021-12-17 2022-03-18 东莞市中镓半导体科技有限公司 Vapor phase epitaxial growth device

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6476998A (en) * 1987-09-17 1989-03-23 Sumitomo Electric Industries Vapor phase growth apparatus for compound semiconductor
CN1384533A (en) * 2002-01-09 2002-12-11 南京大学 Homogeneity improving method and device for hydride gaseous epitaxially groven GaN material
CN101006548A (en) * 2004-06-30 2007-07-25 王望南 Deposition technique for producing high quality compound semiconductor materials
CN101281864B (en) * 2008-01-11 2010-06-02 南京大学 Apparatus for improving hydride vapour phase epitaxy growth GaN material homogeneity
CN102465333A (en) * 2010-11-18 2012-05-23 南京大学 Vertical hydride vapor phase epitaxy growth system
CN105154969A (en) * 2015-10-19 2015-12-16 中国电子科技集团公司第四十六研究所 Single-crystal furnace cavity for improving uniformity of nitride grown by HVPE method

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6476998A (en) * 1987-09-17 1989-03-23 Sumitomo Electric Industries Vapor phase growth apparatus for compound semiconductor
CN1384533A (en) * 2002-01-09 2002-12-11 南京大学 Homogeneity improving method and device for hydride gaseous epitaxially groven GaN material
CN101006548A (en) * 2004-06-30 2007-07-25 王望南 Deposition technique for producing high quality compound semiconductor materials
CN101281864B (en) * 2008-01-11 2010-06-02 南京大学 Apparatus for improving hydride vapour phase epitaxy growth GaN material homogeneity
CN102465333A (en) * 2010-11-18 2012-05-23 南京大学 Vertical hydride vapor phase epitaxy growth system
CN105154969A (en) * 2015-10-19 2015-12-16 中国电子科技集团公司第四十六研究所 Single-crystal furnace cavity for improving uniformity of nitride grown by HVPE method

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114197037A (en) * 2021-12-17 2022-03-18 东莞市中镓半导体科技有限公司 Vapor phase epitaxial growth device

Similar Documents

Publication Publication Date Title
CN102465333B (en) Vertical hydride vapor phase epitaxy growth system
TW544775B (en) Chemical vapor deposition apparatus and chemical vapor deposition method
TWI499085B (en) Growth of group iii-v material layers by spatially confined epitaxy
US10907273B2 (en) Growing epitaxial 3C-SiC on single-crystal silicon
CN104067374B (en) Multiple complementary gas distribution assemblies
US8765501B2 (en) Formation of group III-V material layers on patterned substrates
CN103238203B (en) For utilizing the template layer of the improvement of HVPE technique heteroepitaxial deposition III-nitride semiconductor material
CN109825875A (en) Carrier gas auxiliary PVT method prepares the device and method of wide bandgap semiconductor monocrystal material
CN102465337B (en) Multi-piece multi-source horizontal hydride vapor phase epitaxy growth system
CN106381523A (en) Vertical hydride gas phase epitaxial growth system
JP2789861B2 (en) Organometallic molecular beam epitaxial growth method
US20110263111A1 (en) Group iii-nitride n-type doping
CN100428410C (en) Homogeneity improving method and device for hydride gaseous epitaxially groven GaN material
CN107794567B (en) Method for manufacturing group III nitride semiconductor
CN101383279B (en) HVPE reactor for preparing nitride semiconductor substrate
CN112239889B (en) Method for slowing down gallium nitride deposited on tube wall in halide vapor phase epitaxial growth system and halide vapor phase epitaxial growth system
CN216639708U (en) HVPE device sharing metal source
CN106328772B (en) A kind of preparation method of high quality nitride epitaxial piece
CN108118390A (en) A kind of method and apparatus for improving III- nitride material doping efficiencies in HVPE
JP4590636B2 (en) Method for producing aluminum nitride single crystal
CN212770941U (en) Metal organic compound vapor deposition system
KR100975835B1 (en) Manufacturing Method of Nano-Structures at Low Temperature Using Indium
CN105154969A (en) Single-crystal furnace cavity for improving uniformity of nitride grown by HVPE method
CN101475150A (en) Apparatus for improving HVPE transmission airflow homogeneity
JP2010111556A (en) GROWTH METHOD OF GaN CRYSTAL

Legal Events

Date Code Title Description
C06 Publication
PB01 Publication
C10 Entry into substantive examination
SE01 Entry into force of request for substantive examination
RJ01 Rejection of invention patent application after publication

Application publication date: 20170208

RJ01 Rejection of invention patent application after publication