CN1986870A - Preparing process of graphite target containing dopant element - Google Patents
Preparing process of graphite target containing dopant element Download PDFInfo
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- CN1986870A CN1986870A CN 200610151165 CN200610151165A CN1986870A CN 1986870 A CN1986870 A CN 1986870A CN 200610151165 CN200610151165 CN 200610151165 CN 200610151165 A CN200610151165 A CN 200610151165A CN 1986870 A CN1986870 A CN 1986870A
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- dopant element
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- graphite target
- graphite
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Abstract
The preparation process of graphite target containing dopant element includes the following steps: ball milling mixture of graphite powder and dopant element, vacuum drying, vacuumizing the gap between plastic-rubber jacket and steel cylinder, filling mixture powder, pre-pressing and cold isostatic cold pressing, releasing pressure, sintering and cooling. Thus prepared graphite target containing dopant element has density of 2.06 g/cu cm, low amount of inside residual gas, arc spot diameter as small as 1-5 microns, resistivity not higher than 7.8x10<-5> Ohm.cm and stable arc discharge current.
Description
Technical field
The present invention relates to a kind of preparation method of graphite target.
Background technology
Graphite material is owing to have characteristics such as high temperature resistant, anticorrosive and self-lubricating, thereby obtained application widely in drill bit, the chemical experiment of nuclear reactor, Aeronautics and Astronautics structured material, electrode materials, special purpose with fields such as corrosion-resistant crucible, semiconductor materials.Particularly in diamond or diamond like carbon film deposition field, graphite material is often used as negative electrode target source, graphite cathode target purity requirement height, and the purity of graphite is generally more than 99.99% in the target.The method of traditional preparation process graphite target can't realize the solid phase doping, but with powdered graphite and jointing material (as pitch) gluing, hot moulding makes its hardened forming under high temperature (more than 2000 ℃) then; The graphite target density of this traditional method preparation generally is about 1.8g/cm
3, the cathode arc spot diameter made from the graphite target of this traditional technology preparation that graphite target produced is about 10 μ m, easily produces a large amount of macroscopic particles, can pollute the non-crystal diamond film that cathode arc source makes.In addition, adopt the high-temperature sintering process preparation to contain the graphite target of dopant element at present,, cause dopant element can't reach the content requirement of design because dopant element loses in a large number in sintering process.
Also have two kinds of high pressure die-pressed graphite targets at present except that above known high temperature sintering graphite target, a kind of is that (～250MPa) graphite target, another kind are that Singapore receives the ultra-high voltage (～1550MPa) graphite target of cutting edge of a knife or a sword company for the high pressure of Cambridge University.The high purity graphite powder (99.999%) that Cambridge University adopts particle diameter to be about 1 μ m is a raw material, at room temperature it is applied the about 5min of uniaxial tension about 250MPa, makes the graphite target that varies in size, and the density of this graphite target is about 1.6g/cm
3, but the plasma beam weak strength that it produced, cladding efficient is very low after filtering; And arc spot can form the hole that diameter is about 1mm during by this target surface, and therefore graphite target is very easily split after using 1～2 time.The high purity graphite powder that cutting edge of a knife or a sword company then adopts median size to be about 50 μ m of receiving is a raw material, is heated earlier about 230 ℃, and compression molding under the condition of about 550MPa ultra-high voltage then, the density of this graphite target is 1.8～1.95g/cm
3, because powdered graphite is to be molded under the situation that does not have jointing material, thereby the target that obtains has vesicular structure, resistivity is 8.0 * 10
-5～1.0 * 10
-4Ω cm; Prepare large-scale press device of this graphite target needs and high-strength mould simultaneously, therefore in real work, be difficult to accomplished.
Summary of the invention
The objective of the invention is easily to produce a large amount of macroscopic particles for the graphite target that solves present conventional high-temperature sintering process preparation, prepared film quality when seriously reducing as cathode arc source, the graphite target that contains dopant element of sintering process preparation can't reach the content requirement of design, the plasma beam weak strength that Cambridge University's high pressure die-pressed graphite target produces, cladding efficient is low, easily split and Singapore receives cutting edge of a knife or a sword company ultra-high voltage die-pressed graphite target vesicular structure is arranged, the demanding problem of appointed condition, and a kind of preparation method who contains the graphite target of dopant element who provides.The graphite target that contains dopant element prepares according to the following steps: (one) by the design requirements that contains the dopant element graphite target take by weighing accurately that purity is 99.999%, the dopant element powder of the powdered graphite of particle diameter≤1 μ m and particle diameter≤1 μ m adds planetary ball mill, and be solvent with the industrial spirit, under the condition of 300～400r/min ball milling, mix 2 ± 0.5h; (2) vacuum-drying mixed powder; (3) plastic, rubber is placed in the rigidity cylinder, plastic, rubber cover diameter is extracted the air between plastic, rubber cover and rigidity cylinder inner wall out less than rigidity cylinder interior diameter 1～2cm, and the plastic, rubber cover is close to the rigidity cylinder inner wall; (4) the vacuum drying mixed powder of step (two) is poured into plastic, rubber cover and compacting, extract the air in the plastic, rubber cover of mixed powder upper end afterwards out, with line or rope the upper port of plastic, rubber cover is sealed in a down-to-earth manner again; (5) plastic, rubber that mixed powder will be housed is placed on precompressed 20 ± 5min in 7～8 atmospheric environment, and then puts into cold isostatic press and slowly increase pressure to 280 ± 10MPa, and 280 ± 10MPa, the 4～10min that keep-ups pressure; (6) adopt three grades of destressing method releases, every grade of release time is 6 ± 1min, obtains the graphite base; (7) the graphite base is put into air pressure≤10
-1In the vacuum sintering furnace of Pa, heat-up rate with 10 ℃/min is heated to 600 ± 50 ℃ earlier, and under 600 ± 50 ℃ of conditions, be incubated 20 ± 5min, and then be heated to 1000 ± 200 ℃ with the heat-up rate of 5 ℃/min, and under 1000 ± 200 ℃ of conditions, be incubated 1 ± 0.1h; (8) be cooled to room temperature, promptly obtain containing the graphite target of dopant element.The graphite target densification that contains dopant element that the present invention prepares, mass density reaches 2.06g/cm
3Because graphite target density height, inner residual gas is few, so the hot-fluid that is produced during arc-over can not make target material surface produce more fragment, the arc spot diameter only is 1～5 μ m, reduced of the pollution of macroscopical macrobead, improved the quality of doping non-crystal diamond film arc plasma.The present invention contains in the preparation process of graphite target of dopant element and does not add any tackiness agent, introduces the possibility of other impurity element when having avoided sintering, has guaranteed that the content of the high purity of graphite target and dopant element is constant substantially.The graphite target that the present invention contains dopant element adopts the compression moulding of isostatic cool pressing technology, has avoided the one-way of axial pressure, and prepared graphite target density height, material is even, defective is few, do not ftracture, so the arc erosion target material surface is more stable.Few and little, the good conductivity of graphite target internal void that contains dopant element of the inventive method preparation, resistivity≤7.8 * 10
-5Ω cm, arc-over is stable, the plasma body beam intensity that is produced, the deposition height is 0.7nm/s, the film surface that makes simultaneously is even, macroscopic particles is few, can be widely used in cathode arc source and prepare carbon-base film material field.Present device requires low, the simple easy handling of technology.
Description of drawings
Fig. 1 is that the plastic, rubber cover concerns synoptic diagram with rigidity cylinder position in embodiment one step (three); Fig. 2 is that the plastic, rubber cover concerns synoptic diagram with rigidity cylinder position in the embodiment step (four); Fig. 3 is that doped with boron element graphite target with embodiment 13 preparation is as the prepared boron mixing non-crystal diamond film surface electronic of cathode arc source microscope scintigram; Fig. 4 is the doped with boron element graphite target outside drawing of embodiment 13 preparations.Fig. 5 is dopant element quality percentage composition that adds and the graphite target of the preparing quality percentage composition corresponding relation figure as dopant element in the prepared doping non-crystal diamond film of cathode arc source.
Embodiment
Embodiment one: present embodiment is described in conjunction with Fig. 1 and Fig. 2, the graphite target that contains dopant element prepares according to the following steps: (one) by the design requirements that contains the dopant element graphite target take by weighing accurately that purity is 99.999%, the dopant element powder of the powdered graphite of particle diameter≤1 μ m and particle diameter≤1 μ m adds planetary ball mill, and be solvent with the industrial spirit, under the condition of 300～400r/min ball milling, mix 2 ± 0.5h; (2) vacuum-drying mixed powder; (3) plastic, rubber cover 2 is placed rigidity cylinder 1, plastic, rubber overlaps 2 diameters less than rigidity cylinder 1 interior diameter 1～2cm, extracts the air between plastic, rubber cover 2 and rigidity cylinder 1 inwall out, and plastic, rubber cover 2 is close to rigidity cylinder 1 inwall; (4) the vacuum drying mixed powder 3 of step (two) is poured into plastic, rubber cover 2 and compactings, extract the air in the mixed powder 3 upper end plastic, rubbers covers 2 afterwards out, again with line or restrict and 4 the upper port of plastic, rubber cover 2 sealed in a down-to-earth manner; (5) plastic, rubber that mixed powder will be housed is placed on precompressed 20 ± 5min in 7～8 atmospheric environment, and then puts into cold isostatic press and slowly increase pressure to 280 ± 10MPa, and 280 ± 10MPa, the 4～0min that keep-ups pressure; (6) adopt three grades of destressing method releases, every grade of release time is 6 ± 1min, obtains the graphite base; (7) the graphite base is put into air pressure≤10
-1In the vacuum sintering furnace of Pa, heat-up rate with 10 ℃/min is heated to 600 ± 50 ℃ earlier, and under 600 ± 50 ℃ of conditions, be incubated 20 ± 5min, and then be heated to 1000 ± 200 ℃ with the heat-up rate of 5 ℃/min, and under 1000 ± 200 ℃ of conditions, be incubated 1 ± 0.1h; (8) be cooled to room temperature, promptly obtain containing the graphite target of dopant element.
Air between plastic, rubber cover 2 and rigidity cylinder 1 inwall is extracted out with mechanical pump by rigidity cylinder aspirating hole 1-1 in the present embodiment step (three), immediately with plug 5 sealing rigidity cylinder aspirating hole 1-1.Extract air in the mixed powder 3 upper end plastic, rubbers covers 2 out with mechanical pump in the present embodiment step (four), again with line or restrict and 4 the upper port of plastic, rubber cover 2 sealed in a down-to-earth manner.Present embodiment can contain the dopant element graphite target according to what contain that dopant element graphite target design requirements (the content difference of dopant element) produces different size; The quality percentage composition that dopant element adds and the graphite target of preparing illustrate that dopant element in the doping non-crystal diamond film increases with the quality percentage composition of dopant element in the graphite target as the quality percentage composition corresponding relation of dopant element in the prepared doping non-crystal diamond film of cathode arc source as shown in Figure 5.
The plastic, rubber cover is available from Shenyang the earth latex company in the present embodiment, and the plastic, rubber cover is thick to be 1～2 millimeter.
Embodiment two: the difference of present embodiment and embodiment one is: the dopant element powder in the step () is boron, silicon, iron, aluminium, gold or zinc powder.Other step is identical with embodiment one.
Simple substance exist with solid-state form and fusing point at the element more than 800 ℃, can be except that radiation, toxic or volatile simple substance element are arranged as the dopant element of present embodiment.
Embodiment three: present embodiment and embodiment one or twos' difference is: the dopant element powder in the step () is an iron powder.Other step is identical with embodiment one or two.
Embodiment four: the difference of present embodiment and embodiment one is: vacuum drying atmospheric pressure value is≤10 in the step (two)
-1Pa.Other step is identical with embodiment one.
The dry mixed powder of present embodiment vacuum-drying is for fear of the dopant element oxidation by air.
Embodiment five: present embodiment and embodiment one or twos' difference is: the dopant element powder in the step () is a boron powder.Other step is identical with embodiment one or two.
Embodiment six: the difference of present embodiment and embodiment one is: knock the rigidity cylinder in the step (four) when mixed powder being poured into the plastic, rubber cover.Other step is identical with embodiment one.
It is more even, more fine and close after suppressing that present embodiment can make mixed powder distribute.
Embodiment seven: the difference of present embodiment and embodiment one is: the every work 1h of planetary ball mill rests 1 time in the step (), and be 10～15min unemployed time.Other step is identical with embodiment one.
Present embodiment can effectively be avoided the too high and blast that causes of mixed powder temperature.
Embodiment eight: the difference of present embodiment and embodiment one is: the plastic, rubber cover that mixed powder is housed in the step (five) wraps up with plastics film earlier before putting into cold isostatic press.Other step is identical with embodiment one.
Present embodiment can more effectively prevent that the liquid in the hydropress from infiltrating the plastic, rubber cover.
Embodiment nine: the difference of present embodiment and embodiment one is: the plastic, rubber cover that mixed powder is housed in the step (five) slowly increases pressure to 280 ± 5MPa after putting into cold isostatic press, and 280 ± 5MPa, the 6～8min that keep-ups pressure.Other step is identical with embodiment one.
Embodiment ten: present embodiment with the difference of embodiment one is: in the step () powdered graphite, dopant element powder and industrial spirit under condition at 320～380r/min ball milling, mix 2h.Other step is identical with embodiment one.
Embodiment 11: the difference of present embodiment and embodiment one is: the plastic, rubber cover that mixed powder is housed in the step (five) slowly increases pressure to 280MPa after putting into cold isostatic press, and the 280MPa 5min that keep-ups pressure.Other step is identical with embodiment one.
Embodiment 12: the difference of present embodiment and embodiment one is: adopt in the step (seven) step type to heat up, temperature is insulation 20～30min when reaching 400 ℃, 600 ℃ and 800 ℃.Other step is identical with embodiment one.
Present embodiment can be avoided the explosion of graphite target in the sintering process effectively, improves product percent of pass.
Embodiment 13: the graphite target that present embodiment contains the doped with boron element prepares according to the following steps: (one) accurately takes by weighing by the design requirements that contains doped with boron element graphite target and accounts for that graphite target total mass 98%, purity are 99.999%, the powdered graphite of particle diameter≤1 μ m and the boron powder that accounts for graphite target total mass 2%, particle diameter≤1 μ m add planetary ball mill, and be solvent with the industrial spirit, under the condition of 340～360r/min ball milling, mix 2h; (2) be 10 at vacuum drying atmospheric pressure value
-1Vacuum-drying mixed powder under the condition of Pa; (3) plastic, rubber is placed in the rigidity cylinder, plastic, rubber cover diameter is extracted the air between plastic, rubber cover and rigidity cylinder inner wall out less than rigidity cylinder interior diameter 1～2cm, and the plastic, rubber cover is close to the rigidity cylinder inner wall; (4) the vacuum drying mixed powder of step (two) is poured into plastic, rubber cover and compacting, extract the air in the plastic, rubber cover of mixed powder upper end afterwards out, with line or rope the upper port of plastic, rubber cover is sealed in a down-to-earth manner again; (5) plastic, rubber that mixed powder will be housed is placed on precompressed 20min in 7.5 atmospheric environment, and then puts into cold isostatic press and slowly increase pressure to 280MPa, and the 280MPa 5min that keep-ups pressure; (6) adopt three grades of destressing method releases, every grade of release time is 6min, obtains the graphite base; (7) the graphite base being put into air pressure is 10
-1In the vacuum sintering furnace of Pa, the heat-up rate with 10 ℃/min is heated to 600 ℃ earlier, and is incubated 20min under 600 ℃ of conditions, and then is heated to 1000 ℃ with the heat-up rate of 5 ℃/min, and is incubated 1h under 1000 ℃ of conditions; (8) be cooled to room temperature, promptly obtain containing the graphite target of doped with boron element.
With the graphite target that contains the doped with boron element of present embodiment preparation as cathode arc source, prepared non-crystal diamond film surface electronic microscope scanning result as shown in Figure 3, the non-crystal diamond film surface is evenly, macroscopic particles is few.The graphite target surface-stable that contains the doped with boron element of present embodiment preparation, smoothly as shown in Figure 4.
Claims (7)
1, a kind of preparation method who contains the graphite target of dopant element, it is characterized in that the graphite target that contains dopant element prepares according to the following steps: (one) by the design requirements that contains the dopant element graphite target take by weighing accurately that purity is 99.999%, the dopant element powder of the powdered graphite of particle diameter≤1 μ m and particle diameter≤1 μ m adds planetary ball mill, and be solvent with the industrial spirit, under the condition of 300～400r/min ball milling, mix 2 ± 0.5h; (2) vacuum-drying mixed powder; (3) plastic, rubber is placed in the rigidity cylinder, plastic, rubber cover diameter is extracted the air between plastic, rubber cover and rigidity cylinder inner wall out less than rigidity cylinder interior diameter 1～2cm, and the plastic, rubber cover is close to the rigidity cylinder inner wall; (4) the vacuum drying mixed powder of step (two) is poured into plastic, rubber cover and compacting, extract the air in the plastic, rubber cover of mixed powder upper end afterwards out, with line or rope the upper port of plastic, rubber cover is sealed in a down-to-earth manner again; (5) plastic, rubber that mixed powder will be housed is placed on precompressed 20 ± 5min in 7～8 atmospheric environment, and then puts into cold isostatic press and slowly increase pressure to 280 ± 10MPa, and 280 ± 10MPa, the 4～10min that keep-ups pressure; (6) adopt three grades of destressing method releases, every grade of release time is 6 ± 1min, obtains the graphite base; (7) the graphite base is put into air pressure≤10
-1In the vacuum sintering furnace of Pa, heat-up rate with 10 ℃/min is heated to 600 ± 50 ℃ earlier, and under 600 ± 50 ℃ of conditions, be incubated 20 ± 5min, and then be heated to 1000 ± 200 ℃ with the heat-up rate of 5 ℃/min, and under 1000 ± 200 ℃ of conditions, be incubated 1 ± 0.1h; (8) be cooled to room temperature, promptly obtain containing the graphite target of dopant element.
2, a kind of preparation method who contains the graphite target of dopant element according to claim 1 is characterized in that the dopant element powder in the step () is boron, silicon, iron, aluminium, gold or zinc powder.
3, a kind of preparation method who contains the graphite target of dopant element according to claim 1 is characterized in that vacuum drying atmospheric pressure value≤10 in the step (two)
-1Pa.
4, a kind of preparation method who contains the graphite target of dopant element according to claim 1 is characterized in that knocking the rigidity cylinder in the step (four) when mixed powder being poured into the plastic, rubber cover.
5, a kind of preparation method who contains the graphite target of dopant element according to claim 1 is characterized in that the every work 1h of planetary ball mill rests 1 time in the step (), and be 10～15min unemployed time.
6, a kind of preparation method who contains the graphite target of dopant element according to claim 1 wraps up with plastics film earlier before the plastic, rubber cover that it is characterized in that being equipped with in the step (five) mixed powder is put into cold isostatic press.
7, a kind of preparation method who contains the graphite target of dopant element according to claim 1, after putting into cold isostatic press, the plastic, rubber cover that it is characterized in that being equipped with in the step (five) mixed powder slowly increases pressure to 280MPa, and the 280MPa 5min that keep-ups pressure.
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| CNB2006101511654A CN100451160C (en) | 2006-12-19 | 2006-12-19 | Preparing process of graphite target containing dopant element |
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|---|---|---|---|
| CNB2006101511654A CN100451160C (en) | 2006-12-19 | 2006-12-19 | Preparing process of graphite target containing dopant element |
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| CN100451160C CN100451160C (en) | 2009-01-14 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111320478A (en) * | 2020-03-27 | 2020-06-23 | 有研资源环境技术研究院(北京)有限公司 | Preparation method of carbon-silicon ceramic target material |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101745974B (en) * | 2008-12-17 | 2011-12-14 | 北京有色金属研究总院 | Method for directly preparing high temperature superconductive flat pre-sintered target blank by isostatic pressing method |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0491431A (en) * | 1990-08-01 | 1992-03-24 | Mitsubishi Materials Corp | Sputtering target for formation of high-melting-point metal silicide film |
| US5428882A (en) * | 1993-04-05 | 1995-07-04 | The Regents Of The University Of California | Process for the fabrication of aluminum metallized pyrolytic graphite sputtering targets |
| GB9615548D0 (en) * | 1996-07-24 | 1996-09-04 | Univ Nanyang | Cathode arc source and graphite target |
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2006
- 2006-12-19 CN CNB2006101511654A patent/CN100451160C/en not_active Expired - Fee Related
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111320478A (en) * | 2020-03-27 | 2020-06-23 | 有研资源环境技术研究院(北京)有限公司 | Preparation method of carbon-silicon ceramic target material |
| CN111320478B (en) * | 2020-03-27 | 2022-02-11 | 有研资源环境技术研究院(北京)有限公司 | Preparation method of carbon-silicon ceramic target material |
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