CN107904659A - A kind of epitaxial growth equipment of graphene - Google Patents
A kind of epitaxial growth equipment of graphene Download PDFInfo
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- CN107904659A CN107904659A CN201711184193.0A CN201711184193A CN107904659A CN 107904659 A CN107904659 A CN 107904659A CN 201711184193 A CN201711184193 A CN 201711184193A CN 107904659 A CN107904659 A CN 107904659A
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- C—CHEMISTRY; METALLURGY
- C30—CRYSTAL GROWTH
- C30B—SINGLE-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
- C30B29/00—Single crystals or homogeneous polycrystalline material with defined structure characterised by the material or by their shape
- C30B29/02—Elements
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- C—CHEMISTRY; METALLURGY
- C30—CRYSTAL GROWTH
- C30B—SINGLE-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
- C30B25/00—Single-crystal growth by chemical reaction of reactive gases, e.g. chemical vapour-deposition growth
- C30B25/02—Epitaxial-layer growth
-
- C—CHEMISTRY; METALLURGY
- C30—CRYSTAL GROWTH
- C30B—SINGLE-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
- C30B25/00—Single-crystal growth by chemical reaction of reactive gases, e.g. chemical vapour-deposition growth
- C30B25/02—Epitaxial-layer growth
- C30B25/10—Heating of the reaction chamber or the substrate
- C30B25/105—Heating of the reaction chamber or the substrate by irradiation or electric discharge
-
- C—CHEMISTRY; METALLURGY
- C30—CRYSTAL GROWTH
- C30B—SINGLE-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
- C30B25/00—Single-crystal growth by chemical reaction of reactive gases, e.g. chemical vapour-deposition growth
- C30B25/02—Epitaxial-layer growth
- C30B25/14—Feed and outlet means for the gases; Modifying the flow of the reactive gases
-
- C—CHEMISTRY; METALLURGY
- C30—CRYSTAL GROWTH
- C30B—SINGLE-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
- C30B25/00—Single-crystal growth by chemical reaction of reactive gases, e.g. chemical vapour-deposition growth
- C30B25/02—Epitaxial-layer growth
- C30B25/18—Epitaxial-layer growth characterised by the substrate
Abstract
The invention discloses a kind of epitaxial growth equipment of graphene, is made of source gas body for giving gas transport system (1), epitaxial growth reaction chamber system (2), exhaust treatment system (3), safe-guard system (4), cooling system (5), automatic control system (6)；The source gas body is connected for giving gas transport system (1) with epitaxial growth reaction chamber system (2) by pipeline.The present invention proposes the forming process of grapheme material in SiC substrate being decomposed into two steps：It is that certain structure carbon-coating is formed in surface of SiC by chlorination processing first, followed by carbon-coating is reconstructed into graphene crystal under the induction of SiC substrate by annealing.Reduce interfering with each other for SiC decomposable processes and amorphous carbon layer restructuring procedure, reaction process is clear, clear mechanism, is convenient for growth kinetics theoretical research and technology controlling and process；With stronger novelty.
Description
Technical field
The invention belongs to semiconductor process technique field, more particularly to a kind of epitaxial growth equipment of graphene.
Background technology
Grapheme material has good physical and electric properties, before having great application in national defence and national economy
Scape, but be intended in commercial Application these characteristics to show completely and be not easy to, it is exactly high performance material to first have to solve
Preparation problem, therefore graphene technique with special nature and key equipment driving can be grown in batches and dominate graphene
Application market, and this situation of various as shown by data seems decades to be continued.
Due to importance of the graphene in national defence and national economy, major country and area put into substantial amounts of people in the world
Power material resources are directed to grapheme material preparation research.People so far, have been developed that two kinds of main preparation wafer scale stones
The method of black alkene material：CVD epitaxial growth methods and SiC high temperature pyrolytic cracking (HTP)s.The graphene quality that CVD epitaxial growth methods are prepared compared with
Requirement that is high and disclosure satisfy that scale and large area generation, but be that grapheme material must be from metal the shortcomings that the method
SiO is transferred on substrate2Deng the preparation that device could be carried out on substrate material, the complexity of technology controlling and process is higher, material property
A series of problems, such as losing seriously, and thus bringing process repeatability.
SiC high temperature pyrolytic cracking (HTP)s heat monocrystalline 4H/6H-SiC substrates under a high vacuum or under atmosphere, top layer silicon atom liter
China, the carbon atom reconstruct generation graphene left.This method is considered as to realize that what graphene applied in integrated circuits most has
One of desired approach.The graphene grown on SiC substrate surface need not be shifted, and SiC substrate can make graphene
Stable energy gap is produced, is conducive to improve the switching characteristic of device.And SiC is as wide bandgap semiconductor, its thermal conductivity
High good heat dissipation, is good semi-insulating substrate.By the research and development of decades, SiC material is in microelectronics, MEMS
It is widely studied and applies Deng field, people has had it fairly perfect understanding, and have developed relevant semiconductor machining
Technique, it is preferable with Si processing compatibilities.Compared with other methods, the graphene grown in SiC substrate can be directly whole brilliant
On piece carries out the etching of device or circuit using traditional photoetching and micro-nano processing technology, is directly produced using existing SiC
Technique realize large-scale production, thus on SiC by the wafer level graphene of pyrolysis for growing be prepare RF transistors and
One of solution most promising so far of circuit.
In addition, current 6 inch silicon carbide silicon substrate commercialization, 8 inches and 12 inches of carbofrax material are being researched and developed,
The price of silicon carbide substrates falls below relatively low level, is established to prepare grapheme material on big wafer size SiC on a large scale
Good basis.Common SiC high temperature pyrolytic cracking (HTP)s are higher there are technological temperature at present, the control requirement to vacuum and atmosphere compared with
In place of the deficiencies of height, the process time is longer, thus how the SiC base grapheme materials that faster and better preparations large area holocrystalline is justified
Become very urgent problems.
The content of the invention
The present invention provides a kind of epitaxial growth equipment of graphene, it is intended to solves existing in the prior art above-mentioned scarce
Fall into.
To reach above-mentioned technical purpose, the present invention adopts the following technical scheme that：
A kind of epitaxial growth equipment of graphene, by source gas body for giving gas transport system 1, epitaxial growth reaction chamber system
System 2, exhaust treatment system 3, safe-guard system 4, cooling system 5, automatic control system 6 form；Source gas body is for giving gas
Transportation system 1 is connected with epitaxial growth reaction chamber system 2 by pipeline；Safe-guard system 4 and exhaust treatment system 3, cooling
System 5, automatic control system 6 are electrically connected；Exhaust treatment system 3 is connected with epitaxial growth reaction chamber system 2 by pipeline；Cooling
System 5 is connected with epitaxial growth reaction chamber system 2, exhaust treatment system 3 by pipeline；Automatic control system 5 also with source gas body
For giving gas transport system 1, epitaxial growth reaction chamber system 2 is electrically connected.
Source gas body for give gas transport system 1 by one argon gas to device of air 11, one hydrogen to device of air 12,
The nitrogen of two to device of air 13, one chlorine to device of air 14, one hydrogen chloride to device of air 15, pressure-measuring device
16th, the carbon tetrachloride of flowmeter 17, one to device of air 18, electromagnetic valve 19, directly enter air pipe, be mixed into tracheae
Road, tail gas emptying pipeline composition.
It is straight to device of air 12 and epitaxial growth reaction chamber system 2 to device of air 11, hydrogen by argon gas directly to enter air pipe
Logical pipeline composition, pipeline are equipped with electromagnetic valve 19, pressure-measuring device 16, flowmeter 17 are additionally provided with pipeline in succession.
Pipeline, argon gas that air pipe connects by argon gas to device of air 11 with epitaxial growth reaction chamber system 2 are mixed into gas
After device 11 is connected with the first nitrogen to device of air 131 and argon gas is to device of air 11 and 2 communicating pipe of epitaxial growth reaction chamber system
After pipeline, the argon gas of road connection are connected to device of air 11 with hydrogen to device of air 12 and argon gas is anti-to device of air 11 and epitaxial growth
Answer 2 connecting pipe of chamber system connect pipeline, argon gas connected to device of air 11 with chlorine to device of air 14 after and argon gas give gas dress
11 pipelines connected with 2 connecting pipe of epitaxial growth reaction chamber system, argon gas are put to device of air 11 and hydrogen chloride to device of air 15
After connection and pipeline that argon gas is connected to device of air 11 with 2 connecting pipe of epitaxial growth reaction chamber system, argon gas are to device of air 11
Connected after being connected with the second nitrogen to device of air 132 with argon gas to device of air 11 with 2 connecting pipe of epitaxial growth reaction chamber system
Pipeline, argon gas connected to device of air 11 with carbon tetrachloride to device of air 18 after and argon gas to device of air 11 and epitaxial growth reaction
The pipeline composition of 2 connecting pipe of chamber system connection, each pipeline are equipped with electromagnetic valve 19, pressure-measuring device are additionally provided with each pipeline
16th, flowmeter 17, electromagnetic valve 19.
Pipeline, the first nitrogen that tail gas evacuated tube route argon gas is connected to device of air 11 with exhaust treatment system 3 are filled to gas
Put 131 connected with argon gas to device of air 11 after and the pipe that is connected to device of air 11 with 3 connecting pipe of exhaust treatment system of argon gas
After road, hydrogen are connected to device of air 12 with argon gas to device of air 11 and argon gas is to device of air 11 and 3 communicating pipe of exhaust treatment system
After pipeline that road is connected, chlorine are connected to device of air 14 with argon gas to device of air 11 and argon gas is to device of air 11 and vent gas treatment
After pipeline that 3 connecting pipe of system is connected, hydrogen chloride are connected to device of air 15 with argon gas to device of air 11 and argon gas gives gas dress
Put 11 pipelines being connected with 3 connecting pipe of exhaust treatment system, carbon tetrachloride connects to device of air 18 with argon gas to device of air 11
Formed after logical with argon gas to the pipeline that device of air 11 is connected with 3 connecting pipe of exhaust treatment system, each pipeline is equipped with pressure
Measuring instrument 16, flowmeter 17, electromagnetic valve 19.
Epitaxial growth reaction chamber system 2 includes reative cell 21, mixing chamber 22, graphite substrate 23, reative cell head cover 24, graphite
Support arm 25, head cover fixed arm 26, infrared radiation thermometer 27, RF radio heaters 28；The top of reative cell 21 is equipped with reative cell head cover
24, reative cell head cover 24 is fixedly connected with head cover fixed arm 26, its position is fixed by head cover fixed arm 26；Graphite support arm 25 is set
Put in reative cell 21, one end is connected with 21 bottom of reative cell, and one end is connected with graphite substrate 23, and graphite substrate 23 is by graphite branch
Brace 25 is supported in reative cell 21；Winding is equipped with RF radio heaters 28 on 21 outer wall of reative cell, and 21 inner top of reative cell is also
Equipped with infrared radiation thermometer 27；Reative cell 21 is connected with mixing chamber 22 by pipeline.
RF radio heaters 28 are made of intermediate frequency power supply 281, external compensating electric capacity 282, induction coil 283, intermediate frequency power supply
281 are electrically connected with external compensating electric capacity 282, and induction coil 283 is electrically connected with external compensating electric capacity 282；Induction coil 283 is by wall
Copper tube of the thickness more than 1mm or square copper pipe are made.
Mixing chamber 22 is cylindric, and upper top offers the air intake 211 of some cellular distributions, is internally provided with even gas
Piece 212, on even gas piece 212 perforation be equipped with some even stomatas 213 in cellular distribution；22 bottom of mixing chamber be equipped with it is cylindric go out
Gas port 214, offers air outlet passage 215 on its side wall.
Exhaust treatment system 3 is by hydrogen treat device 31, chloride treatment device 32,33 groups of intermediate product processing unit
Into；Intermediate product processing unit 33 and source gas body are for giving gas transport system 1, epitaxial growth reaction chamber system 2 passes through pipeline
It is connected, the other end is connected with chloride treatment device 32 by pipeline, 32 other end of chloride treatment device and hydrogen treat
Device 31 is connected by pipeline.
Intermediate product processing unit 33 is made of mechanical pump 331, absorbent charcoal adsorption tank 332, both are connected by pipeline,
Mechanical pump 331 gives gas transport system 1 with the confession of source gas body, the reative cell 21 of epitaxial growth reaction chamber system 2 connects；Chloride
Processing unit 32 is made of spray packed tower 321, circulating water pool 322, suction pump 323, spray packed tower 321, circulating water pool
322nd, suction pump 323 is interconnected by pipeline, and spray packed tower 321 is connected with absorbent charcoal adsorption tank 332 by pipeline；Hydrogen
Processing unit 31 is made of combustion of hydrogen device 311, exhaust blower 312, both are connected by pipeline, combustion of hydrogen device 311 with
Spray packed tower 321 is connected by pipeline；Absorbent charcoal adsorption tank 332, spray packed tower 321, all set in combustion of hydrogen device 311
There is temperature inductor 34.
Safe-guard system 4 is electrically connected with infrared radiation thermometer 27, temperature inductor 34, receives real time temperature feedback, and
Feed back to automatic control system 6.
Cooling system 5 is made of cold water storage tank, water pipe, is additionally provided with electromagnetism folding valve on both connected pipelines, electromagnetism is opened
Valve is closed to be electrically connected with PLC controller 61；Cold water storage tank and reative cell 21, absorbent charcoal adsorption tank 332, spray packed tower 321, hydrogen
Gas burner 311 is connected by pipeline.
Automatic control system 6 is made of PLC controller 61, display screen 62；PLC controller 61 is electrically connected with display screen 62.
Using above technical scheme, have the advantages that：
(1) present invention proposes the forming process of grapheme material in SiC substrate being decomposed into two steps：It is to pass through chlorination first
Processing forms certain structure carbon-coating in surface of SiC, followed by carbon-coating is reconstructed into graphite under the induction of SiC substrate by annealing
Alkene crystal.Reducing interfering with each other for SiC decomposable processes and amorphous carbon layer restructuring procedure, reaction process is clear, clear mechanism,
It is convenient for growth kinetics theoretical research and technology controlling and process.Especially propose that introducing the transition metal such as Cu makees in the process of annealing
For the catalysis of carbon-coating reconstruct, CVD method and SiC pyrolysismethods are prepared graphene and combined, there is stronger novelty.
(2) research to CDC process dynamics mathematical model and related property condition, multidirectional material stream and energy are passed through
The research of stream, and the research of temperature field evolution rule, design thermal field, and energy stabilization uniformly grows chamber system, to reach single
The demand of 6 inches of homogeneous samples of secondary growth 3 piece.Combination pressure tester, flowmeter, full Intellectual computer system and secondary dilute
Release, the technology such as intelligence shunting, which is realized, adulterates the accurate N of C films.To source gas body, reaction intraventricular pressure is strong, reaction time and above-mentioned
Relaxation process in factor change realizes that the accurate control of material thickness is realized in accurate control and intelligence learning.
(3) CDC principles are based on, propose the temperature for making surface of SiC form multi-layer graphene using the method for chlorine reaction-annealing
Degree (less than 1000) substantially reduces compared with the pyrolysismethod (more than 1400 degrees centigrade) of mainstream, and the process time is obviously shortened, from
And requirement of the preparation of graphene to process conditions and equipment is reduced, and the preparation efficiency of material increases substantially, and also makes
Future is prepared on Si/3C-SiC substrates and the lower large area wafer level graphene of the more preferable cost of Si processing compatibilities becomes more
Add easily.Take the lead in proposing by the use of CCl4 as reacting gas, the deposit of C atoms is on the one hand carried out in surface of SiC, one side Cl is former
Son makes the precipitation of Si atoms leave C atoms with SiC reactions, and C sources are provided from two approach for the formation of follow-up graphene.
Brief description of the drawings
Fig. 1 is the system block diagram of the present invention；
Fig. 2 is that source gas body of the present invention supplies to give the gas circuit connection figure of gas transport system；
Fig. 3 is the structure diagram of reative cell of the present invention；
Fig. 4 is the circuit diagram of RF radio heaters of the present invention；
Fig. 5 is the structure diagram of mixing chamber of the present invention；
Fig. 6 is the sectional view of mixing chamber of the present invention；
Fig. 7 is the connection diagram of exhaust treatment system of the present invention.
Specific embodiment
Below in conjunction with the accompanying drawings, embodiment, is further described this programme.
As shown in Figure 1, a kind of epitaxial growth equipment of graphene, by source gas body for giving gas transport system 1, extension life
Long reactor chamber systems 2, exhaust treatment system 3, safe-guard system 4, cooling system 5, automatic control system 6 form；Source gas body
Connected for giving gas transport system 1 with epitaxial growth reaction chamber system 2 by pipeline；Safe-guard system 4 and vent gas treatment
System 3, cooling system 5, automatic control system 6 are electrically connected；Exhaust treatment system 3 passes through pipe with epitaxial growth reaction chamber system 2
Road connects；Cooling system 5 is connected with epitaxial growth reaction chamber system 2, exhaust treatment system 3 by pipeline；Automatic control system 5
Also gas transport system 1 is given with the confession of source gas body, epitaxial growth reaction chamber system 2 is electrically connected.
As shown in Fig. 2, source gas body is for giving gas transport system 1 by hydrogen of the argon gas of one to device of air 11, one
To device of air 12, two nitrogen to device of air 13, one chlorine to device of air 14, one hydrogen chloride to device of air 15,
Pressure-measuring device 16, the carbon tetrachloride of flowmeter 17, one to device of air 18, electromagnetic valve 19, directly enter air pipe, mixed
It is incorporated into air pipe, tail gas emptying pipeline composition.
It is straight to device of air 12 and epitaxial growth reaction chamber system 2 to device of air 11, hydrogen by argon gas directly to enter air pipe
Logical pipeline composition, pipeline are equipped with electromagnetic valve 19, pressure-measuring device 16, flowmeter 17 are additionally provided with pipeline in succession.
Pipeline, argon gas that air pipe connects by argon gas to device of air 11 with epitaxial growth reaction chamber system 2 are mixed into gas
After device 11 is connected with the first nitrogen to device of air 131 and argon gas is to device of air 11 and 2 communicating pipe of epitaxial growth reaction chamber system
After the pipeline argon gas of road connection is connected to device of air 11 with hydrogen to device of air 12 and argon gas is anti-to device of air 11 and epitaxial growth
Answer 2 connecting pipe of chamber system connect pipeline, argon gas connected to device of air 11 with chlorine to device of air 14 after and argon gas give gas dress
11 pipelines connected with 2 connecting pipe of epitaxial growth reaction chamber system, argon gas are put to device of air 11 and hydrogen chloride to device of air 15
After connection and pipeline that argon gas is connected to device of air 11 with 2 connecting pipe of epitaxial growth reaction chamber system, argon gas are to device of air 11
Connected after being connected with the second nitrogen to device of air 132 with argon gas to device of air 11 with 2 connecting pipe of epitaxial growth reaction chamber system
Pipeline, argon gas connected to device of air 11 with carbon tetrachloride to device of air 18 after and argon gas to device of air 11 and epitaxial growth reaction
The pipeline composition of 2 connecting pipe of chamber system connection, each pipeline are equipped with electromagnetic valve 19, pressure-measuring device are additionally provided with each pipeline
16th, flowmeter 17, electromagnetic valve 19.
Pipeline, the first nitrogen that tail gas evacuated tube route argon gas is connected to device of air 11 with exhaust treatment system 3 are filled to gas
Put 131 connected with argon gas to device of air 11 after and the pipe that is connected to device of air 11 with 3 connecting pipe of exhaust treatment system of argon gas
After road, hydrogen are connected to device of air 12 with argon gas to device of air 11 and argon gas is to device of air 11 and 3 communicating pipe of exhaust treatment system
After pipeline that road is connected, chlorine are connected to device of air 14 with argon gas to device of air 11 and argon gas is to device of air 11 and vent gas treatment
After pipeline that 3 connecting pipe of system is connected, hydrogen chloride are connected to device of air 15 with argon gas to device of air 11 and argon gas gives gas dress
Put 11 pipelines being connected with 3 connecting pipe of exhaust treatment system, carbon tetrachloride connects to device of air 18 with argon gas to device of air 11
Formed after logical with argon gas to the pipeline that device of air 11 is connected with 3 connecting pipe of exhaust treatment system, each pipeline is equipped with pressure
Measuring instrument 16, flowmeter 17, electromagnetic valve 19.
By above device, by the reaction source gas Cl of growth response2、HCL、CCL4, high-purity is that reaction gas is again quarter
Lose the H of gas2, be protective gas again be carrier gas high-purity Ar, according to user setting it is quantitative utilization carrier gas Ar to its into
Row is transported in the mixing chamber 23 of epitaxial growth reaction chamber system 2 after uniformly diluting.After the reaction residual gas by pipeline into
Enter to exhaust treatment system 3.In order to accurately control N doping concentrations, growing environment is necessary for high vacuum, so necessary before growth
The pressure of growth chamber is controlled 1 × 10 with molecular pump-7Within mbar.In order to eliminate stream of the growth gasses when entering reative cell
Amount hysteresis or flow overshoot, the pressure directly entered between air pipe and tail gas emptying pipeline two-way is zero, and gas can lead to
6 electromagnetic valve for adjusting door of automatic control system, 19 folding is crossed by directly entering air pipe into reative cell 21 or by tail gas emptying pipeline
Emptying.
Whole source gas body is controlled for giving gas transport system 1 using digital flowmeter, and control accuracy is 1%
Within, it can be achieved that being accurately controlled to the flow of growth atmosphere gas.Since N doping influences to show on epitaxial graphene characteristic
Write, therefore N adulterated and accurately to be controlled, devise nitrogen directly doping and secondary dilution and adulterate two gas circuits, realize
Doping ultralow to nitrogen and highly doped accurate control.
Epitaxial growth reaction chamber system 2 includes reative cell 21, mixing chamber 22, graphite substrate 23, reative cell head cover 24, graphite
Support arm 25, head cover fixed arm 26, infrared radiation thermometer 27, RF radio heaters 28；As shown in figure 3, the top of reative cell 21 is equipped with
Reative cell head cover 24, reative cell head cover 24 are fixedly connected with head cover fixed arm 26, its position is fixed by head cover fixed arm 26；Graphite
Support arm 25 is arranged in reative cell 21, and one end is connected with 21 bottom of reative cell, and one end is connected with graphite substrate 23, graphite substrate
23 are supported in reative cell 21 by graphite support arm 25；Winding is equipped with RF radio heaters 28, reative cell on 21 outer wall of reative cell
21 inner tops are additionally provided with infrared radiation thermometer 27；Reative cell 21 is connected with mixing chamber 22 by pipeline.Carrying out graphene extension life
When long, various ratio datas are inputted in automatic control system 6, the control of automatic control system 6 opens source gas body for giving gas fortune
Defeated system 1, epitaxial growth reaction chamber system 2 is passed through by gas, while RF radio heaters 28 begin to warm up carry out chloridization process,
Gas reaction in reative cell 21, subsequent RF radio heaters 28 stop heating, anneal, the gas discharge after reaction.
As shown in figure 4, RF radio heaters 28 are by intermediate frequency power supply 281, external compensating electric capacity 282,283 groups of induction coil
Into intermediate frequency power supply 281 is electrically connected with external compensating electric capacity 282, induction coil 283 and external compensating electric capacity 282；Induction coil
283 are made of copper tube of the wall thickness more than 1mm or square copper pipe.The strong flux of polarization instantaneous variation passes through in induction coil 283
Lead to whole heating object, the direction opposite with heated current, will produce corresponding very big vortex flow.Due to heating object
In vivo there are internal resistance, so many Joule heats can be produced, the temperature of object itself is set to increase rapidly.In order to ensure high power,
Φ more than 8 need to be used, wall thickness is more than the copper tube of 1mm, and square copper pipe is to reduce same thermal losses and then improve the efficiency of heating surface, at the same time
Induction coil need to use longer copper pipe coiling to obtain big inductance value.Induction coil should isolate with intermediate frequency power supply to be linked.Simultaneously as magnetic
Beam passes through sample stage, causes a sample stage temperature field to differ, thus is necessary to optimize sample stage shape and makes its table
Temperature field is identical at each point of face.
As shown in figure 5, mixing chamber 22 is cylindric, upper top offers the air intake 211 of some cellular distributions；Such as figure
6, mixing chamber 22 is internally provided with even gas piece 212, is penetrated through on even gas piece 212 and is equipped with some even stomatas 213 in cellular distribution；It is mixed
22 bottom of gas chamber is equipped with cylindric gas outlet 214, and air outlet passage 215 is offered on its side wall.
The present invention is intended to first produce C films in SiC substrates, and then annealing obtains uniform high-quality graphene, therefore carbon film
Uniformity seem particularly significant.And to obtain uniform C films, another key factor is just in addition to requiring uniform temperature field
It is the homogeneity stability of fluid in reative cell 21.Therefore mixing chamber 22 is especially set according to chlorination and annealing process
Meter.Mixing chamber 22 is designed to according to the growth kinetics result of study of SiC chlorination reactions at least two layers of structure, reacting gas
Air intake 211 through mixing chamber 22 enters 22 upper strata of mixing chamber, then passes through the even stomata on even gas piece 212 in cellular distribution
213 enter lower floor.Different reacting gas, growth kinetics is different, thus the structure of corresponding mixing chamber 22 also has difference, because
This, carries out with changing mixing chamber 22 according to corresponding process conditions.
As shown in fig. 7, exhaust treatment system 3 is by hydrogen treat device 31, chloride treatment device 32, intermediate product processing
Device 33 forms；Intermediate product processing unit 33 is with source gas body for giving gas transport system 1, epitaxial growth reaction chamber system 2
Be connected by pipeline, the other end is connected with chloride treatment device 32 by pipeline, 32 other end of chloride treatment device with
Hydrogen treat device 31 is connected by pipeline.
Intermediate product processing unit 33 is made of mechanical pump 331, absorbent charcoal adsorption tank 332, both are connected by pipeline,
Mechanical pump 331 gives gas transport system 1 with the confession of source gas body, the reative cell 21 of epitaxial growth reaction chamber system 2 connects；Chloride
Processing unit 32 is made of spray packed tower 321, circulating water pool 322, suction pump 323, spray packed tower 321, circulating water pool
322nd, suction pump 323 is interconnected by pipeline, and spray packed tower 321 is connected with absorbent charcoal adsorption tank 332 by pipeline；Hydrogen
Processing unit 31 is made of combustion of hydrogen device 311, exhaust blower 312, both are connected by pipeline, combustion of hydrogen device 311 with
Spray packed tower 321 is connected by pipeline；Absorbent charcoal adsorption tank 332, spray packed tower 321, all set in combustion of hydrogen device 311
There is temperature inductor 34.
Hydrogen is carried out to handle with the burning that oxygen directly reacts, but this burning cannot carry out under naked light, hydrogen
Mixed with air and meet naked light and can explode, therefore combustion of hydrogen device 311 is surface contact reaction unit, its external 220V, 50Hz
Power supply, heats the copper pipe being internally provided with by electromagnetic coil, and copper pipe, which is heated, to redden, at this moment by the hydrogen of copper pipe with
In copper pipe surface, by thermal response, at the same time, control is fixed to the flow of hydrogen tail gas, so as to ensure hydrogen tail gas in air
Safe handling.
Absorbing liquid is uniformly sprayed at packing layer top by the spray equipment at the top of it when spray packed tower 321 works
Portion, and be in membranaceous flowing from top to bottom along packing layer, and exhaust gas then enters from tower lower part, is discharged through packing layer from tower top.
In the process, exhaust gas is forced direction is varied multiple times, speed is constantly collided with absorbing liquid, contacted, and exhaust gas is being filled out with absorbing liquid
The reaction time is come into full contact with the bed of material, make in exhaust gas harmful components can absorbed liquid fully absorb purification.Alkali in order to prevent
Liquid or acid liquid corrosion circulating water pool 322, circulating water pool 322 are made using certain thickness hard polythene material.By lye with
Sour gas reaction in preparation process, generates corresponding salt and is dissolved in lye, achieve the purpose that to exhaust sour gas.
The method that absorbent charcoal adsorption tank 332 uses activated carbon adsorption for intermediate reaction thing, using this method absorption efficiency
Up to more than 90%.
At the same time temperature inductor 34 by temperature feedback in system to safe-guard system 4 to ensure safety.
Safe-guard system 4 is electrically connected with infrared radiation thermometer 27, temperature inductor 34, receives real time temperature feedback, and
Feed back to automatic control system 6.
Cooling system 5 is made of cold water storage tank, water pipe, is additionally provided with electromagnetism folding valve on both connected pipelines, electromagnetism is opened
Valve is closed to be electrically connected with PLC controller 61；Cold water storage tank and reative cell 21, absorbent charcoal adsorption tank 332, spray packed tower 321, hydrogen
Gas burner 311 is connected by pipeline.
Automatic control system 6 is made of PLC controller 61, display screen 62；PLC controller 61 is electrically connected with display screen 62.
Embodiment 1
The manipulator of close seal closure, Dual-arm is additionally provided with outside reative cell 21, sealing is kept during epitaxial growth
State, the graphite support arm 25, head cover fixed arm 26, the manipulator of Dual-arm are electrically connected with automatic control system 6.
All components are in seal closure.At work, various proportional numbers are inputted in automatic control system 6 first
According to the control of automatic control system 6 opens source gas body for giving gas transport system 1, and gas is passed through epitaxial growth reaction chamber system
System 2 carries out chloridization process.After the completion of, argon gas is progressively passed through in reative cell 21 makes intracavitary pressure reach atmospheric pressure, while close
The argon gas of an atmospheric pressure is also passed into sealing cover.When pressure reaches balance, upper cover is lifted by head cover fixed arm 26, in reative cell 21
Graphite support arm 25 lift graphite substrate 23 and make on upper surface and vacuum tube along maintaining an equal level；Metal is taken by the manipulator of Dual-arm again
Film is placed on chip, and intracavitary single shaft mechanical arm declines so that sample stage reaches heating location and made annealing treatment.Annealing is completed
Afterwards, graphite support arm 25 performs same work and takes out metal film and chip.Above process whole process is controlled by computer and realized.Profit
Can be to avoid the waste of time and materials during the cooling and temperature-rise period that manual operation is brought and this, whole with this design
, it is necessary to accurately be controlled the change for reacting chamber pressure, temperature, mechanical process etc. in a operating process.Own in the system
Component all realizes modularization detachable.
The above is only the preferred embodiment of the present invention, it is noted that for the ordinary skill people of the art
Member, without departing from the principle of the present invention, can also make some improvement and supplement, these are improved and supplement also should be regarded as
Protection scope of the present invention.
Claims (10)
- A kind of 1. epitaxial growth equipment of graphene, it is characterised in that：By source gas body for giving gas transport system (1), extension Growth response chamber system (2), exhaust treatment system (3), safe-guard system (4), cooling system (5), automatic control system (6) Composition；The source gas body is connected for giving gas transport system (1) with epitaxial growth reaction chamber system (2) by pipeline；It is described Safe-guard system (4) is electrically connected with exhaust treatment system (3), cooling system (5), automatic control system (6)；At the tail gas Reason system (3) is connected with epitaxial growth reaction chamber system (2) by pipeline；The cooling system (5) and epitaxial growth reaction chamber System (2), exhaust treatment system (3) are connected by pipeline；The automatic control system (5) is also with source gas body for giving gas fortune Defeated system (1), epitaxial growth reaction chamber system (2) are electrically connected.
- A kind of 2. epitaxial growth equipment of graphene as claimed in claim 1, it is characterised in that：The source gas body is for giving gas Body transportation system (1) is filled to device of air (11), the hydrogen of one by the argon gas of one to device of air (12), the nitrogen of two to gas Put (13), the chlorine of one is surveyed to device of air (14), the hydrogen chloride of one to device of air (15), pressure-measuring device (16), flow Amount instrument (17), the carbon tetrachloride of one to device of air (18), electromagnetic valve (19), directly enter air pipe, be mixed into air pipe, tail Gas emptying pipeline composition；It is described that directly to enter air pipe be to device of air (12) and epitaxial growth reaction chamber system by argon gas to device of air (11), hydrogen (2) the pipeline composition directly connected, pipeline are equipped with electromagnetic valve (19), pressure-measuring device (16), flow are additionally provided with pipeline Measuring instrument (17)；Pipeline, the argon gas for being mixed into air pipe and being connected by argon gas to device of air (11) with epitaxial growth reaction chamber system (2) After being connected to device of air (11) with the first nitrogen to device of air (131) and argon gas is to device of air (11) and epitaxial growth reaction chamber system Filled after pipeline, the argon gas of system (2) connecting pipe connection are connected to device of air (11) with hydrogen to device of air (12) with argon gas to gas Pipeline, argon gas that (11) are connected with epitaxial growth reaction chamber system (2) connecting pipe is put to fill to gas to device of air (11) and chlorine Put pipeline, the argon gas that after (14) connect and argon gas is connected to device of air (11) with epitaxial growth reaction chamber system (2) connecting pipe After being connected to device of air (11) with hydrogen chloride to device of air (15) and argon gas is to device of air (11) and epitaxial growth reaction chamber system (2) after pipeline, the argon gas of connecting pipe connection are connected to device of air (11) with the second nitrogen to device of air (132) and argon gas is to gas Pipeline that device (11) is connected with epitaxial growth reaction chamber system (2) connecting pipe, argon gas are to device of air (11) and carbon tetrachloride After being connected to device of air (18) and the pipeline that is connected to device of air (11) with epitaxial growth reaction chamber system (2) connecting pipe of argon gas Composition, each pipeline are equipped with electromagnetic valve (19), and pressure-measuring device (16), flowmeter (17), electricity are additionally provided with each pipeline Magnet valve door (19)；Pipeline that tail gas evacuated tube route argon gas is connected to device of air (11) with exhaust treatment system (3), the first nitrogen to After device of air (131) is connected with argon gas to device of air (11) and argon gas is to device of air (11) and exhaust treatment system (3) communicating pipe After pipeline that road is connected, hydrogen are connected to device of air (12) with argon gas to device of air (11) and argon gas is to device of air (11) and tail After pipeline that gas processing system (3) connecting pipe is connected, chlorine are connected to device of air (14) with argon gas to device of air (11) and Pipeline that argon gas is connected to device of air (11) with exhaust treatment system (3) connecting pipe, hydrogen chloride are to device of air (15) and argon Gas to device of air (11) connect after and argon gas be connected to device of air (11) with exhaust treatment system (3) connecting pipe pipeline, After carbon tetrachloride is connected to device of air (18) with argon gas to device of air (11) and argon gas is to device of air (11) and exhaust treatment system (3) the pipeline composition that connecting pipe is connected, each pipeline are equipped with pressure-measuring device (16), flowmeter (17), solenoid valve Door (19).
- A kind of 3. epitaxial growth equipment of graphene as claimed in claim 1, it is characterised in that：The epitaxial growth reaction chamber System (2) include reative cell (21), mixing chamber (22), graphite substrate (23), reative cell head cover (24), graphite support arm (25), Head cover fixed arm (26), infrared radiation thermometer (27), RF radio heaters (28)；Reaction ceiling is equipped with the top of the reative cell (21) Cover (24), reative cell head cover (24) is fixedly connected with head cover fixed arm (26), its position is fixed by head cover fixed arm (26)；It is described Graphite support arm (25) is arranged in reative cell (21), and one end is connected with reative cell (21) bottom, one end and graphite substrate (23) Connection, the graphite substrate (23) are supported in reative cell (21) by graphite support arm (25)；On reative cell (21) outer wall Winding is equipped with RF radio heaters (28), and reative cell (21) inner top is additionally provided with infrared radiation thermometer (27)；The reative cell (21) Connected with mixing chamber (22) by pipeline.
- A kind of 4. graphene epitaxial growth equipment as claimed in claim 3, it is characterised in that：The RF radio heaters (28) By intermediate frequency power supply (281), external compensating electric capacity (282), induction coil (283) forms, the intermediate frequency power supply (281) and external benefit Capacitance (282) is repaid, is electrically connected, induction coil (283) is electrically connected with external compensating electric capacity (282)；The induction coil (283) by Copper tube of the wall thickness more than 1mm or square copper pipe are made.
- A kind of 5. epitaxial growth equipment of graphene as claimed in claim 3, it is characterised in that：The mixing chamber (22) is circle Column, upper top offer the air intake (211) of some cellular distributions, are internally provided with even gas piece (212), the even gas piece (212) perforation is equipped with some even stomatas (213) in cellular distribution on；Mixing chamber (22) bottom is equipped with cylindric outlet Mouthful (214), offer air outlet passage (215) on its side wall.
- A kind of 6. epitaxial growth equipment of graphene as claimed in claim 1, it is characterised in that：Exhaust treatment system (3) by Hydrogen treat device (31), chloride treatment device (32), intermediate product processing unit (33) composition；The intermediate product processing Device (33) gives gas transport system (1) with the confession of source gas body, epitaxial growth reaction chamber system (2) is connected by pipeline, separately One end is connected with chloride treatment device (32) by pipeline, chloride treatment device (32) other end and hydrogen treat device (31) connected by pipeline.
- A kind of 7. epitaxial growth equipment of graphene as claimed in claim 6, it is characterised in that：The intermediate product processing dress Put (33) to be made of mechanical pump (331), absorbent charcoal adsorption tank (332), both are connected by pipeline, the mechanical pump (331) Gas transport system (1) is given with the confession of source gas body, the reative cell (21) of epitaxial growth reaction chamber system (2) connects；The chlorination Thing processing unit (32) is made of spray packed tower (321), circulating water pool (322), suction pump (323), the spray packed tower (321), circulating water pool (322), suction pump (323) are interconnected by pipeline, and the spray packed tower (321) is inhaled with activated carbon Attached tank (332) is connected by pipeline；The hydrogen treat device (31) is by combustion of hydrogen device (311), exhaust blower (312) group Into both are connected by pipeline, and the combustion of hydrogen device (311) is connected with spray packed tower (321) by pipeline；The work Property charcoal adsorption tanks (332), spray packed tower (321), be designed with temperature inductor (34) in combustion of hydrogen device (311).
- A kind of 8. epitaxial growth equipment of graphene as claimed in claim 1, it is characterised in that：Safe-guard system (4) with Infrared radiation thermometer (27), temperature inductor (34) are electrically connected, and receive real time temperature feedback, and feed back to automatic control system (6)。
- A kind of 9. epitaxial growth equipment of graphene as claimed in claim 1, it is characterised in that：The cooling system (5) by Cold water storage tank, water pipe form, and electromagnetism folding valve, electromagnetism folding valve and PLC controller (61) are additionally provided with both connected pipelines It is electrically connected；Cold water storage tank and reative cell (21), absorbent charcoal adsorption tank (332), spray packed tower (321), combustion of hydrogen device (311) connected by pipeline.
- A kind of 10. epitaxial growth equipment of graphene as claimed in claim 1, it is characterised in that：The automatic control system (6) it is made of PLC controller (61), display screen (62)；PLC controller (61) is electrically connected with display screen (62).
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