CN102505141A - Graphene preparation method based on Cu film assisted annealing - Google Patents
Graphene preparation method based on Cu film assisted annealing Download PDFInfo
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- CN102505141A CN102505141A CN201210000366XA CN201210000366A CN102505141A CN 102505141 A CN102505141 A CN 102505141A CN 201210000366X A CN201210000366X A CN 201210000366XA CN 201210000366 A CN201210000366 A CN 201210000366A CN 102505141 A CN102505141 A CN 102505141A
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Abstract
The invention discloses a graphene preparation method based on Cu film assisted annealing, which is used mainly for solving the problems of small area, poor continuity and nonuniform layering of graphene preparation in the prior art. The method includes: firstly, growing a carbonized layer for transition on a Si substrate 4-12 inches in size; secondly, growing a 3C-SiC heteroepitaxal film at the temperature of 1100 DEG C to 1250 DEG C, and using C3H8 and SiH4 as growth source gases; thirdly, allowing 3C-SiC to react with gaseous CCl4 at 800-1000 DEG C to generate a double-layer carbon film; fourthly, placing a carbon side of the double-layer carbon film sample on a Cu film; and fifthly, placing the double-layer carbon film and the Cu film in Ar atmosphere, and annealing at 900-1100 DEG C for 10-25 minutes to generate double-layer graphene. The double-layer graphene generated by the method has smooth surface, is large in area and low in porosity, and can be used for sealing gases and liquids.
Description
Technical field
The invention belongs to microelectronics technology, relate to a kind of semiconductor film material and preparation method thereof, specifically be based on the graphene preparation method of Cu film auxiliary annealing.
Technical background
It is in 2004 that Graphene appears in the laboratory, and at that time, two scientist An Delie Jim of Univ Manchester UK and the Ke Siteyanuowo Lip river husband that disappears found that they can obtain more and more thinner graphite flake with a kind of very simple method.They separate graphite flake from graphite, the two sides with thin slice is bonded on a kind of special adhesive tape then, tears adhesive tape, just can be divided into two graphite flake.Operation so constantly, last so thin slice is more and more thinner, they have obtained the thin slice that only is made up of one deck carbon atom, Here it is Graphene.From now on, the novel method of preparation Graphene emerges in an endless stream, but uses maximum mainly contain following two kinds:
1. chemical vapour deposition CVD method provides a kind of effective ways of controlled preparation Graphene; It is with planar substrates; Place the decomposable presoma of high temperature like mf, metal single crystal etc.; In atmosphere such as methane, ethene, make carbon atom be deposited on substrate surface through high temperature annealing and form Graphene, at last with obtaining independently graphene film after the chemical corrosion method removal metal base.The growth of the adjustable Graphenes of parameter such as flow of the type through selecting substrate, the temperature of growth, presoma; Like growth velocity, thickness, area etc.; The maximum shortcoming of this method is that the lamella and the substrate that obtain interact strong; Lost the character of many single-layer graphenes, and the continuity of Graphene not fine.
2. thermolysis SiC method: to remove Si through lip-deep SiC is decomposed, residual subsequently carbon forms Graphene with the monocrystal SiC heating.Yet the monocrystal SiC that uses in the SiC thermolysis is very expensive, and the Graphene that grows out is island and distributes, and the number of plies is inhomogeneous, and size is less, is difficult to large-area manufacturing Graphene.
Summary of the invention
The objective of the invention is to avoid the deficiency of above-mentioned prior art; A kind of graphene preparation method based on Cu film auxiliary annealing is proposed; To improve surface flatness and continuity, reduce porosity, to reduce cost, be implemented in large-area manufacturing Graphene on the 3C-SiC substrate.
For realizing above-mentioned purpose, preparation method of the present invention may further comprise the steps:
(1) the Si substrate base to the 4-12 inch carries out standard cleaning;
(2) the Si substrate base after will cleaning is put into CVD system response chamber, reaction chamber is vacuumized reach 10
-7The mbar rank;
(3) at H
2Progressively be warming up to 900 ℃-1100 ℃ of carbonization temperatures under the situation of protection, feeding flow is the C of 40ml/min
3H
8, substrate is carried out carbonization 3-8min, growth one deck carburization zone;
(4) be warming up to 1100 ℃-1250 ℃ of growth temperatures rapidly, feed C
3H
8And SiH
4, carry out 3C-SiC hetero epitaxy growth for Thin Film, the time is 35-70min, then at H
2Protection progressively is cooled to room temperature down, accomplishes the growth of 3C-SiC epitaxial film;
(5) the good 3C-SiC print of will growing places silica tube, is heated to 800-1000 ℃;
(6) to CCl is housed
4The there-necked flask of liquid is heated to 60-80 ℃, utilizes Ar gas to carry CCl
4Steam gets in the silica tube and reacts with 3C-SiC, generates double-deck carbon film, and the Ar gas velocity is 30-85ml/min, and the reaction times is 30-120min;
The carbon face of the double-deck carbon film print that (7) will generate places on the Cu film, together places Ar gas to be 900-1100 ℃ in temperature them again and anneals 10-25 minute down, make double-deck carbon film reconstitute double-layer graphite alkene, the Cu film is taken away from double-layer graphite alkene again.
The present invention compared with prior art has following advantage:
The present invention since growth during 3C-SiC earlier on the Si substrate growth one deck carburization zone as transition, and then growth 3C-SiC, thereby the 3C-SiC quality of growth is high.
But the present invention since the 3C-SiC heteroepitaxial growth on the Si disk, and Si disk size can reach 12 inches, thus with this method can growing large-area Graphene, and low price.
3. the present invention is owing to utilize 3C-SiC and CCl
4Gas reaction, thereby the double-layer graphite alkene smooth surface that generates, porosity is low, can be used for the sealing to gas and liquid.
4. the present invention anneals owing to being utilized on the Cu film, thereby the easier reconstruct of the carbon film that generates forms continuity Graphene preferably.
Description of drawings
Fig. 1 is the device synoptic diagram that the present invention prepares Graphene;
Fig. 2 is the schema that the present invention prepares Graphene.
Embodiment
With reference to Fig. 1, preparation equipment of the present invention is mainly by three-way valve 3, there-necked flask 8, and water-bath 9, silica tube 5, resistance furnace 6 is formed; Three-way valve 3 links to each other with silica tube 5 through first channel 1, link to each other with the left side mouth of there-necked flask 8 through second passage 2, and the right side mouth of there-necked flask 8 links to each other with silica tube 5, and CCl is housed in the there-necked flask
4Liquid, and it is placed in the water-bath 9, and silica tube 5 is placed in the resistance furnace 6.
With reference to Fig. 2, making method of the present invention provides following three kinds of embodiment.
Embodiment 1
Step 1: remove the sample surfaces pollutent.
4 inches Si substrate bases are carried out cleaning surfaces handle, promptly use NH earlier
4OH+H
2O
2Reagent soaked sample 10 minutes, took out the back oven dry, to remove the sample surfaces organic residue; Re-use HCl+H
2O
2Reagent soaked sample 10 minutes, took out the back oven dry, to remove ionic contamination.
Step 2: the Si substrate base is put into CVD system response chamber, reaction chamber is vacuumized reach 10
-7The mbar rank.
Step 3: growth carburization zone.
At H
2Under the situation of protection reaction chamber temperature is risen to 900 ℃ of carbonization temperatures, feeding flow to reaction chamber then is the C of 40ml/min
3H
8, growth one deck carburization zone on the Si substrate, growth time is 8min.
Step 4: growth 3C-SiC epitaxial film on carburization zone.
Reaction chamber temperature is risen to 1100 ℃ of growth temperatures rapidly, feed the SiH that flow is respectively 15ml/min and 30ml/min
4And C
3H
8, carrying out 3C-SiC hetero epitaxy growth for Thin Film, growth time is 70min; Then at H
2Protection progressively is cooled to room temperature down, accomplishes the growth of 3C-SiC epitaxial film.
Step 5: with the 3C-SiC print silica tube of packing into, and the exhaust heating.
(5.1) the good 3C-SiC epitaxial film print of will growing takes out from CVD system response chamber and is placed on the silica tube 5, places silica tube the thermal site that receives of resistance furnace 6;
(5.2) resistance to air loss of the whole preparation equipment of inspection, feeding flow velocitys from inlet mouth 4 is the Ar gas of 80ml/min, and utilizes three-way valve 3 control Ar gas to get into from first channel 1 silica tube was carried out emptying 30 minutes, and air in the silica tube 7 is discharged from the air outlet;
(5.3) open the resistance furnace power switch, be warming up to 800 ℃.
Step 6: the double-deck carbon film of growing.
(6.1) bath 9 power supplys of fetching boiling water are to being equipped with CCl
4The there-necked flask 8 of liquid is heated to 60 ℃;
(6.2) after resistance furnace reaches 800 ℃ of setting, the swivel tee valve, making flow velocity is that the Ar gas of 30ml/min flows into there-necked flasks from second passage 2, and carries CCl
4Steam gets into silica tube, makes gaseous state CCl
4React in silica tube with 3C-SiC, generate double-deck carbon film, the reaction times is 30 minutes.
Step 7: reconstitute double-layer graphite alkene.
The double-deck carbon film print that (7.1) will generate takes out from silica tube, and its carbon face is placed on the thick Cu film of 250nm;
(7.2) double-deck carbon film print and Cu film integral body being placed flow velocity is the Ar gas of 40ml/min, is 900 ℃ of annealing 25 minutes down in temperature, and the katalysis through metal Cu makes double-deck carbon film more easily reconstitute successive double-layer graphite alkene;
(7.3) the Cu film is taken away from double-layer graphite alkene print.
Embodiment 2
Step 1: remove the sample surfaces pollutent.
8 inches Si substrate bases are carried out cleaning surfaces handle, promptly use NH earlier
4OH+H
2O
2Reagent soaked sample 10 minutes, took out the back oven dry, to remove the sample surfaces organic residue; Re-use HCl+H
2O
2Reagent soaked sample 10 minutes, took out the back oven dry, to remove ionic contamination.
Step 2: the Si substrate base is put into CVD system response chamber, reaction chamber is vacuumized reach 10
-7The mbar rank.
Step 3: growth carburization zone.
At H
2Under the situation of protection reaction chamber temperature is risen to 1000 ℃ of carbonization temperatures, feeding flow to reaction chamber then is the C of 40ml/min
3H
8, growth one deck carburization zone on the Si substrate, growth time is 6min.
Step 4: growth 3C-SiC epitaxial film on carburization zone.
Reaction chamber temperature is risen to 1150 ℃ of growth temperatures rapidly, feed the SiH that flow is respectively 30ml/min and 60ml/min
4And C
3H
8, carrying out 3C-SiC hetero epitaxy growth for Thin Film, growth time is 45min; Then at H
2Protection progressively is cooled to room temperature down, accomplishes the growth of 3C-SiC epitaxial film.
Step 5: with the 3C-SiC print silica tube of packing into, and the exhaust heating.
The 3C-SiC epitaxial film print that growth is good takes out from CVD system response chamber and is placed on the silica tube 5, places silica tube the thermal site that receives of resistance furnace 6; Check the resistance to air loss of whole preparation equipment, feeding flow velocity from inlet mouth 4 is the Ar gas of 80ml/min, and utilizes three-way valve 3 control Ar gas to get into from first channel 1 silica tube was carried out emptying 30 minutes, makes air 7 discharges from the air outlet in the silica tube; Open the resistance furnace power switch, be warming up to 900 ℃.
Step 6: the double-deck carbon film of growing.
Bath 9 power supplys of fetching boiling water are to being equipped with CCl
4The there-necked flask 8 of liquid is heated to 70 ℃; Reach 900 ℃ of setting when resistance furnace after, the swivel tee valve, making flow velocity is that the Ar gas of 60ml/min flows into there-necked flasks from second passage 2, and carries CCl
4Steam gets into silica tube, makes gaseous state CCl
4React in silica tube with 3C-SiC, generate double-deck carbon film, the reaction times is 60 minutes.
Step 7: reconstitute double-layer graphite alkene.
The double-deck carbon film print that generates is taken out from silica tube, its carbon face is placed on the thick Cu film of 280nm; Again they together being placed flow velocity is that the Ar gas temperature of 60ml/min is 1000 ℃ of annealing 20 minutes down, and the katalysis through metal Cu makes double-deck carbon film more easily reconstitute successive double-layer graphite alkene; Again the Cu film is taken away from double-layer graphite alkene print.
Embodiment 3
Steps A: 12 inches Si substrate bases are carried out cleaning surfaces handle, promptly use NH earlier
4OH+H
2O
2Reagent soaked sample 10 minutes, took out the back oven dry, to remove the sample surfaces organic residue; Re-use HCl+H
2O
2Reagent soaked sample 10 minutes, took out the back oven dry, to remove ionic contamination.
Step B: the Si substrate base is put into CVD system response chamber, reaction chamber is vacuumized reach 10
-7The mbar rank.
Step C: at H
2Under the situation of protection reaction chamber temperature is risen to 1100 ℃ of carbonization temperatures, feeding flow to reaction chamber then is the C of 40ml/min
3H
8, continue 3min, with growth one deck carburization zone on the Si substrate.
Step D: reaction chamber temperature is risen to 1250 ℃ of growth temperatures rapidly, feed the SiH that flow is respectively 35ml/min and 70ml/min
4And C
3H
8, carry out 3C-SiC hetero epitaxy growth for Thin Film 35min; Then at H
2Protection progressively is cooled to room temperature down.
Step e: the good 3C-SiC epitaxial film print of will growing takes out from CVD system response chamber and is placed on the silica tube 5, places silica tube the thermal site that receives of resistance furnace 6; Reexamine the resistance to air loss of whole preparation equipment, feeding flow velocity from inlet mouth 4 is the Ar gas of 80ml/min, and utilizes three-way valve 3 control Ar gas to get into from first channel 1 silica tube was carried out emptying 30 minutes, makes air 7 discharges from the air outlet in the silica tube; Open the resistance furnace power switch at last, be warming up to 1000 ℃.
Step F: bath 9 power supplys of fetching boiling water, to CCl is housed
4The there-necked flask 8 of liquid is heated to 70 ℃; Reach 1000 ℃ of setting when resistance furnace after, the swivel tee valve, making flow velocity is that the Ar gas of 85ml/min flows into there-necked flasks from second passage 2, and carries CCl
4Steam gets into silica tube, makes gaseous state CCl
4In silica tube, reacted 120 minutes with 3C-SiC, generate double-deck carbon film.
Step G: the double-deck carbon film print that will generate takes out from silica tube, and earlier its carbon face being placed thickness is on the Cu film of 300nm; Again they together being placed flow velocity is the Ar gas of 100ml/min, is 1100 ℃ of down annealing 10 minutes in temperature, and the katalysis through metal Cu makes double-deck carbon film more easily reconstitute successive double-layer graphite alkene; At last the Cu film is taken away from double-layer graphite alkene print.
Claims (4)
1. graphene preparation method based on Cu film auxiliary annealing may further comprise the steps:
(1) the Si substrate base to the 4-12 inch carries out standard cleaning;
(2) the Si substrate base after will cleaning is put into CVD system response chamber, reaction chamber is vacuumized reach 10
-7The mbar rank;
(3) at H
2Progressively be warming up to 900 ℃-1100 ℃ of carbonization temperatures under the situation of protection, feeding flow is the C of 40ml/min
3H
8, substrate is carried out carbonization 3-8min, growth one deck carburization zone;
(4) be warming up to 1100 ℃-1250 ℃ of growth temperatures rapidly, feed C
3H
8And SiH
4, carry out 3C-SiC hetero epitaxy growth for Thin Film, the time is 35-70min, then at H
2Protection progressively is cooled to room temperature down, accomplishes the growth of 3C-SiC epitaxial film;
(5) the good 3C-SiC print of will growing places silica tube, is heated to 800-1000 ℃;
(6) to CCl is housed
4The there-necked flask of liquid is heated to 60-80 ℃, utilizes Ar gas to carry CCl
4Steam gets in the silica tube and reacts with 3C-SiC, generates double-deck carbon film, and the Ar gas velocity is 30-85ml/min, and the reaction times is 30-120min;
The carbon face of the double-deck carbon film print that (7) will generate places on the Cu film, together places Ar gas to be 900-1100 ℃ in temperature them again and anneals 10-25 minute down, make double-deck carbon film reconstitute double-layer graphite alkene, the Cu film is taken away from double-layer graphite alkene again.
2. the graphene preparation method based on Cu film auxiliary annealing according to claim 1 is characterized in that the described feeding of step (4) SiH
4And C
3H
8, its flow is respectively 15-35ml/min and 30-70ml/min.
3. the graphene preparation method based on Cu film auxiliary annealing according to claim 1, the flow velocity of Ar gas is 40-100ml/min when it is characterized in that said step (7) annealing.
4. the graphene preparation method based on Cu film auxiliary annealing according to claim 1 is characterized in that the Cu film thickness in the said step (7) is 250-300nm.
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2013102359A1 (en) * | 2012-01-03 | 2013-07-11 | 西安电子科技大学 | Method for preparing graphene on sic substrate based on annealing with assistant metal film |
| WO2013102360A1 (en) * | 2012-01-03 | 2013-07-11 | 西安电子科技大学 | Method for preparing graphene by reaction with cl2 based on annealing with assistant metal film |
| CN105112999A (en) * | 2015-09-09 | 2015-12-02 | 中国计量科学研究院 | Method for preparing monocrystal graphene |
| CN105483824A (en) * | 2016-01-11 | 2016-04-13 | 信阳师范学院 | Method for preparing monocrystal double-layer graphene |
| US9951418B2 (en) | 2012-05-23 | 2018-04-24 | Xidian University | Method for preparing structured graphene on SiC substrate based on Cl2 reaction |
| CN110408990A (en) * | 2019-07-31 | 2019-11-05 | 中国电子科技集团公司第十三研究所 | The preparation method of single crystal graphene |
-
2012
- 2012-01-03 CN CN201210000366XA patent/CN102505141A/en active Pending
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| Title |
|---|
| 《CARBON》 20100821 Jian Sui et al The formation of a dual-layer carbon film on silicon carbide using a combination of carbide-derived carbon process and chemical vapor deposition in a CCl4-containing atmosphere 第732-736页 1-4 第49卷, 第2期 * |
| A.OUERGHI ET AL: "Epitaxial graphene on cubic SiC(111)/Si(111) substrate", 《APPLIED PHYSICS LETTERS》 * |
| A.OUERGHI ET AL: "Structural coherency of epitaxial graphene on 3C-SiC(111) epilayers on Si(111)", 《APPLIED PHYSICS LETTERS》 * |
| JIAN SUI ET AL: "The formation of a dual-layer carbon film on silicon carbide using a combination of carbide-derived carbon process and chemical vapor deposition in a CCl4-containing atmosphere", 《CARBON》 * |
| SREEKAR BHAVIRIPUDI ET AL: "Role of kinetic factors in chemical vapor deposition synthesis of uniform large area grapheme using copper catalyst", 《NANOLETTERS》 * |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2013102359A1 (en) * | 2012-01-03 | 2013-07-11 | 西安电子科技大学 | Method for preparing graphene on sic substrate based on annealing with assistant metal film |
| WO2013102360A1 (en) * | 2012-01-03 | 2013-07-11 | 西安电子科技大学 | Method for preparing graphene by reaction with cl2 based on annealing with assistant metal film |
| US9048092B2 (en) | 2012-01-03 | 2015-06-02 | Xidian University | Process for preparing graphene based on metal film-assisted annealing and the reaction with Cl2 |
| US9691612B2 (en) | 2012-01-03 | 2017-06-27 | Xidian University | Process for preparing graphene on a SiC substrate based on metal film-assisted annealing |
| US9951418B2 (en) | 2012-05-23 | 2018-04-24 | Xidian University | Method for preparing structured graphene on SiC substrate based on Cl2 reaction |
| CN105112999A (en) * | 2015-09-09 | 2015-12-02 | 中国计量科学研究院 | Method for preparing monocrystal graphene |
| CN105112999B (en) * | 2015-09-09 | 2017-11-28 | 中国计量科学研究院 | A kind of method for preparing single crystal graphene |
| CN105483824A (en) * | 2016-01-11 | 2016-04-13 | 信阳师范学院 | Method for preparing monocrystal double-layer graphene |
| CN110408990A (en) * | 2019-07-31 | 2019-11-05 | 中国电子科技集团公司第十三研究所 | The preparation method of single crystal graphene |
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Application publication date: 20120620 |