JPH02301586A - Production of high-purity copper - Google Patents
Production of high-purity copperInfo
- Publication number
- JPH02301586A JPH02301586A JP12176989A JP12176989A JPH02301586A JP H02301586 A JPH02301586 A JP H02301586A JP 12176989 A JP12176989 A JP 12176989A JP 12176989 A JP12176989 A JP 12176989A JP H02301586 A JPH02301586 A JP H02301586A
- Authority
- JP
- Japan
- Prior art keywords
- cathode
- vacuum
- copper
- purity
- purity copper
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 239000010949 copper Substances 0.000 title claims abstract description 51
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 title claims abstract description 28
- 229910052802 copper Inorganic materials 0.000 title claims abstract description 26
- 238000004519 manufacturing process Methods 0.000 title claims description 6
- 238000002844 melting Methods 0.000 claims abstract description 9
- 230000008018 melting Effects 0.000 claims abstract description 9
- 229910021591 Copper(I) chloride Inorganic materials 0.000 claims abstract description 8
- OXBLHERUFWYNTN-UHFFFAOYSA-M copper(I) chloride Chemical compound [Cu]Cl OXBLHERUFWYNTN-UHFFFAOYSA-M 0.000 claims abstract description 8
- 229940045803 cuprous chloride Drugs 0.000 claims abstract description 8
- 150000004820 halides Chemical class 0.000 claims abstract description 6
- 239000002994 raw material Substances 0.000 claims abstract description 3
- 239000003960 organic solvent Substances 0.000 claims description 7
- 230000003647 oxidation Effects 0.000 claims description 3
- 238000007254 oxidation reaction Methods 0.000 claims description 3
- 239000012535 impurity Substances 0.000 abstract description 15
- 238000005868 electrolysis reaction Methods 0.000 abstract description 4
- 238000009825 accumulation Methods 0.000 abstract description 3
- 229910052739 hydrogen Inorganic materials 0.000 abstract description 3
- 229910052757 nitrogen Inorganic materials 0.000 abstract description 3
- 230000001590 oxidative effect Effects 0.000 abstract description 3
- 239000002904 solvent Substances 0.000 abstract 2
- 238000000034 method Methods 0.000 description 9
- 238000007670 refining Methods 0.000 description 8
- 230000000694 effects Effects 0.000 description 4
- POKOASTYJWUQJG-UHFFFAOYSA-M 1-butylpyridin-1-ium;chloride Chemical compound [Cl-].CCCC[N+]1=CC=CC=C1 POKOASTYJWUQJG-UHFFFAOYSA-M 0.000 description 3
- UHOVQNZJYSORNB-UHFFFAOYSA-N Benzene Chemical compound C1=CC=CC=C1 UHOVQNZJYSORNB-UHFFFAOYSA-N 0.000 description 3
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 description 3
- 239000007789 gas Substances 0.000 description 3
- 229910052799 carbon Inorganic materials 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 229910052760 oxygen Inorganic materials 0.000 description 2
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 description 1
- 238000013019 agitation Methods 0.000 description 1
- 150000004945 aromatic hydrocarbons Chemical class 0.000 description 1
- 229910052785 arsenic Inorganic materials 0.000 description 1
- 238000005266 casting Methods 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 238000011109 contamination Methods 0.000 description 1
- 229910000365 copper sulfate Inorganic materials 0.000 description 1
- ARUVKPQLZAKDPS-UHFFFAOYSA-L copper(II) sulfate Chemical compound [Cu+2].[O-][S+2]([O-])([O-])[O-] ARUVKPQLZAKDPS-UHFFFAOYSA-L 0.000 description 1
- 238000004070 electrodeposition Methods 0.000 description 1
- 239000003792 electrolyte Substances 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000004744 fabric Substances 0.000 description 1
- 238000009472 formulation Methods 0.000 description 1
- 238000002309 gasification Methods 0.000 description 1
- 239000011261 inert gas Substances 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000000155 melt Substances 0.000 description 1
- 238000010309 melting process Methods 0.000 description 1
- 239000012528 membrane Substances 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 125000004108 n-butyl group Chemical group [H]C([H])([H])C([H])([H])C([H])([H])C([H])([H])* 0.000 description 1
- 238000000746 purification Methods 0.000 description 1
- 238000011403 purification operation Methods 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- 229910052717 sulfur Inorganic materials 0.000 description 1
- 229910052725 zinc Inorganic materials 0.000 description 1
- 238000004857 zone melting Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
- C23C14/22—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material characterised by the process of coating
- C23C14/34—Sputtering
- C23C14/3407—Cathode assembly for sputtering apparatus, e.g. Target
- C23C14/3414—Metallurgical or chemical aspects of target preparation, e.g. casting, powder metallurgy
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は高純度銅、特に純度９９．９９９〜９９、９９
９９ ｖ１％以上の導電特性、軟質、低温軟化特性に優
れた高純度銅の製造方法に関するものである。DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention is directed to high-purity copper, particularly purity 99.999-99.99.
The present invention relates to a method for producing high-purity copper that has excellent conductivity, softness, and low-temperature softening properties of 99 v1% or more.
一般に電気銅は純度９９．９５〜９９．９９％で、通常
０２を１００〜５００ｐｐｍ含有するタフピッチ銅と、
０□を５〜２０ｐｐｍ含有する無酸素銅として利用され
、半導体などのボンディングワイヤー、スパッターター
ゲット、軟質圧延プリント配線。Generally, electrolytic copper has a purity of 99.95 to 99.99%, and is usually tough pitch copper containing 100 to 500 ppm of 02.
It is used as oxygen-free copper containing 5 to 20 ppm of 0□, and is used in bonding wires for semiconductors, sputter targets, and soft rolled printed wiring.
オーディオ用細電線等に用いられている。Used in thin electrical wires for audio, etc.
これ等は何れも電気分解により、粗銅中のＰｂ、’ Ｓ
ｂ、Ｎｉ、Ｂｉ、Ａｓ、Ｆｅ、Ｚｎ等の不純物を高い精
錬効率で分離したもので、通常Ｃｕより貴なＡｇや卑で
ある前記不純物の外に、Ｓ、Ｏ，Ｃ等が微量含まれてお
り、これ等不純物は高純度銅の特性に有害である。All of these are Pb, 'S in blister copper by electrolysis.
Impurities such as Ni, Bi, As, Fe, and Zn are separated with high refining efficiency.In addition to the above impurities, such as Ag, which is nobler than Cu, and the base impurities, it contains trace amounts of S, O, C, etc. These impurities are harmful to the properties of high-purity copper.
このためより高純度銅を必要とする場合には、ゾーンメ
ルティング、フロートメルティング又は薄部などの乾式
方法が行なわれているが、何れも製造コストが高い方法
である。For this reason, when higher purity copper is required, dry methods such as zone melting, float melting, and thin section are used, but all of these methods are expensive to manufacture.
高純度銅を得るための上記乾式方法は、原料銅を高温で
繰り返し何度も溶融、凝固を行なうため、熱エネルギー
を多量に消費し、かつ精製速度が著しく低く、また設備
費が非常に大きいものである。従ってこれ等の方法に代
る経済的な高純度銅の精製方法の開発が強く求められて
いる。The above dry method for obtaining high-purity copper repeatedly melts and solidifies raw copper at high temperatures, which consumes a large amount of thermal energy, has an extremely low refining rate, and has very high equipment costs. It is something. Therefore, there is a strong demand for the development of an economical method for refining high-purity copper in place of these methods.
これに必要な条件としては、
（１）高純度、即ち純度９９．９９９〜９９．９９９９
ｗ１％（以下Ｗ１％を％と略記）又はこれ以上の純銅
を経済的に攪産することができること。The conditions necessary for this are: (1) High purity, that is, purity 99.999 to 99.9999
It is possible to economically produce pure copper of w1% (hereinafter W1% is abbreviated as %) or more.
（２）高純度銅の特性に特に有害な不純物、例えばＳ、
Ｏ，Ｃを効率的に除去できること。(2) Impurities that are particularly harmful to the properties of high-purity copper, such as S,
Ability to efficiently remove O and C.
（３）通常の工業的電解法及びこれを複数回繰り返して
も排除できない不純物を能率良く排除できること。(3) It is possible to efficiently remove impurities that cannot be removed even by using a normal industrial electrolytic method and repeating this process multiple times.
このように単に従来の工業的方法を繰り返すのでは達せ
られない精錬度か得られることである。In this way, it is possible to obtain a degree of refinement that cannot be achieved by simply repeating conventional industrial methods.
本発明はこれに鑑み種々検討の結果、特に９９、９９９
〜９９．９９９９％以上の高純度で、導電特性。In view of this, the present invention has been developed as a result of various studies, and in particular, 99,999
High purity of ~99.9999% or more and conductive properties.
軟質、低温軟化特性に優れた高純度銅の製造方法を開発
したもので、原料にＡｇ含有匿が低いＣｕアノードを用
い、Ａｇ含有量が低い塩化第１銅とアルキルピリンニウ
ムハロゲン化物の有機溶媒浴を電解浴として、電解処理
し、得られたカソード銅を真空中で溶解するか、又はカ
ソードＣｕに酸化処理と還元処理を施してから真空中で
溶解することを特徴とするものである。We have developed a method for producing high-purity copper that is soft and has excellent low-temperature softening properties, using a Cu anode with low Ag content as the raw material, and an organic solvent of cuprous chloride and alkylpyrinnium halide with low Ag content. The method is characterized by performing electrolytic treatment using an electrolytic bath and melting the obtained cathode copper in a vacuum, or by subjecting the cathode Cu to an oxidation treatment and a reduction treatment and then melting it in a vacuum.
即ち本発明は、Ａｇ含有量が低いＣｕアノードを、Ａｇ
含有量が低い塩化第１銅とアルキルピリジニウムハロゲ
ン化物の有機溶媒浴からなる電解浴で電解精製し、得ら
れたカソードＣｕを真空中で溶解するか、又はカソード
Ｃｕを酸化処理と還元処理してから真空中で溶解するこ
とにより、カッ〜ドＣｕ中のＨ，Ｎ、Ｏ等のガス成分及
びＣ等の微量不純物をガス化又は酸化物としてとり除き
、５Ｎ〜６ Ｎ （９９，９９９〜９９、９９９９％）
以上のの高純度銅を得るものである。しかしてＣｕアノ
ード中のＡｇ含有量はてきる限り低いことが有利であり
、通常１ ｐｐｍ以下とすることが望ましい。またその
他の不純物は市販の電気銅レベルで良い。That is, the present invention provides a Cu anode with a low Ag content.
Electrolytic refining is performed in an electrolytic bath consisting of an organic solvent bath of cuprous chloride and alkylpyridinium halide having low contents, and the resulting cathode Cu is dissolved in a vacuum, or the cathode Cu is subjected to oxidation treatment and reduction treatment. Gas components such as H, N, O, etc. and trace impurities such as C in Cu are removed by gasification or as oxides by melting in vacuum from 5N to 6N (99,999 to 99 , 9999%)
The above-mentioned high-purity copper can be obtained. Therefore, it is advantageous for the Ag content in the Cu anode to be as low as possible, and it is usually desirable to keep it below 1 ppm. Other impurities may be at the level of commercially available electrolytic copper.
本発明は上記の如く電解浴は塩化第１銅（Ｃｏｃｋ）と
アルキルピリジニウムハロゲン化物、例えばブチルピリ
ジニウムクロリド（ＢＰＣ）を含む有機溶媒浴を電解浴
として電解精製することにより、電解浴中のＡｇの蓄積
を防ぎ、通常精製しにくいＡｇのカソード電着を避け、
他の不純物に対する精製効果を得、純度５〜６ Ｎ （
９９，９９９〜９９．９９９９％）レベルの高純度銅の
経済的な製造を可能にしたものである。As described above, the present invention uses an organic solvent bath containing cuprous chloride (Cock) and an alkylpyridinium halide, such as butylpyridinium chloride (BPC), for electrolytic refining, thereby removing Ag in the electrolytic bath. Prevents accumulation and avoids cathodic electrodeposition of Ag, which is usually difficult to purify.
Obtained purification effect against other impurities, purity 5-6 N (
This makes it possible to economically produce high-purity copper with a purity level of 99,999% to 99.9999%.
電解浴は非酸化性の雰囲気下で使用し、塩化第１銅中の
Ａｇ含有量はＬ ｐｐｍ以下であることが望ましい。ま
た塩化第１銅とアルキルピリジニウムハロゲン化物の濃
度比はモル比で１／４〜４７１程度が良い。非酸化性の
雰囲気ガスとしてはＮ２．Ａｒ、Ｈｅ、Ｃｏ、等の不活
性ガスを用いる。また有機溶媒としてはベンゼン、トル
エン等の芳香族炭化水素の１種又は２種以上を配合して
用いる。浴温は０〜１５０℃、電流密度は０１〜３０＾
／ｄ’ｒｒｒの範囲内とする。また電解浴の拡拌は液の
強制循環１機械的拡拌等により十分に行なう。電解浴へ
の外部からの異物の混入や不純物の蓄積等に対しては多
孔質の樹脂膜。The electrolytic bath is preferably used in a non-oxidizing atmosphere, and the Ag content in cuprous chloride is preferably L ppm or less. Further, the concentration ratio of cuprous chloride and alkylpyridinium halide is preferably about 1/4 to 471 in terms of molar ratio. As a non-oxidizing atmospheric gas, N2. An inert gas such as Ar, He, Co, etc. is used. Further, as the organic solvent, one or more aromatic hydrocarbons such as benzene and toluene are used in combination. Bath temperature is 0~150℃, current density is 01~30^
/d'rrr. Further, the electrolytic bath is sufficiently agitated by forced circulation of the liquid, mechanical agitation, etc. A porous resin membrane prevents foreign matter from entering the electrolytic bath from outside and the accumulation of impurities.
濾布、セラミック板でアノード室とカソード室を分離す
るか、電解浴全体を循環濾過する。Separate the anode and cathode chambers with a filter cloth or ceramic plate, or circulate and filter the entire electrolytic bath.
Ｃｕアノード中の不純物レベルが高い場合や、長時間連
続的に電解処理を行なう場合には、電解液量を増加する
か、又はその一部を連続的に電解処理と並行して抜き出
し、新配合の電解浴と交換する等の浄液操作を行なう。When the level of impurities in the Cu anode is high or when electrolytic treatment is performed continuously for a long time, increase the amount of electrolyte or continuously extract a part of it in parallel with electrolytic treatment to create a new formulation. Perform liquid purification operations such as replacing the electrolytic bath with another one.
上記電解精製についで行なう溶解工程は、高真空下にお
ける通常の方法でよいが、特に外部からの汚染を防止す
ることは当然であり、溶解条件（真空度、温度、保持時
間等）と鋳造条件（温度１時間、ルツボ材質等）は製品
純銅中の不純物が最小となるように適宜選択する。これ
によりカッーＦＣｕ中の主な不純物でガスとして除去で
きる成分（Ｈ，Ｎ、 Ｏ等）が減少し、カソードの純度
が大巾に向上する。The melting process that follows the electrolytic refining described above may be carried out in a normal manner under high vacuum, but it is of course necessary to prevent contamination from the outside, and the melting conditions (degree of vacuum, temperature, holding time, etc.) and casting conditions (Temperature for 1 hour, crucible material, etc.) are appropriately selected so that impurities in the pure copper product are minimized. As a result, the main impurities in KaFCu that can be removed as gases (H, N, O, etc.) are reduced, and the purity of the cathode is greatly improved.
また有機溶媒浴の使用によるカソードＣｕ中へのＣの残
留は少ないが、これを更に低減させるためには、上記の
真空溶解に先立って電解後のカソードＣｕを酸化又は／
及び還元処理することで容易に除去され、高純度の金属
Ｃｕを得ることができる。Furthermore, although the amount of C remaining in the cathode Cu due to the use of an organic solvent bath is small, in order to further reduce this, the cathode Cu after electrolysis must be oxidized or /
It is easily removed by a reduction treatment, and highly pure metal Cu can be obtained.
以下本発明の実施例について説明する。 Examples of the present invention will be described below.
Ａｇ含有量が１ ｐｐｍの塩化第１銅と１−ブチルビデ
ジニウムクロリド（ＢＰＣ）をモル比で３７１に配合し
、有機溶媒に溶かした溶融塩浴中で、Ａｇ含有量がｉｐ
ｐｍであるＣｕアノードの電解精製を行なった。このよ
うにして得られたカソードＣｕを真空溶解により鋳造し
た。これを分析したところ銅純度は９９．９９９９％で
あった。Cuprous chloride with an Ag content of 1 ppm and 1-butyl bidedinium chloride (BPC) were mixed at a molar ratio of 371, and the Ag content was ip in a molten salt bath dissolved in an organic solvent.
Electrolytic refining of a pm Cu anode was performed. The cathode Cu thus obtained was cast by vacuum melting. When this was analyzed, the copper purity was 99.9999%.
比較のため同じＣｕアノードを硫酸銅からなる電解浴を
用い、通常の銅電解精製を行ない、得られたカソードＣ
ｕを実施例と同様に真空溶解した。このようにして得ら
れた高純度銅を分析したところ銅純度は、９９．９９９
％であった。For comparison, the same Cu anode was subjected to ordinary copper electrolytic refining using an electrolytic bath made of copper sulfate, and the resulting cathode C
u was vacuum-dissolved in the same manner as in the example. When the high purity copper thus obtained was analyzed, the copper purity was 99.999.
%Met.
このように本発明によれば、生産性が高い安価な方法で
、純度９９．９９９〜９９．９９９９％以上の高純度銅
が得られるもので、工業上顕著な効果を奏する。As described above, according to the present invention, high-purity copper having a purity of 99.999 to 99.9999% or more can be obtained by a highly productive and inexpensive method, and has a remarkable industrial effect.
Claims (1)
有量が低い塩化第１銅とアルキルピリジニウムハロゲン
化物の有機溶媒浴を電解浴として電解処理し、得られた
カソードＣｕを真空中で溶解するか、又はカソードＣｕ
に酸化処理と還元処理を施してから真空中で溶解するこ
とを特徴とする高純度銅の製造方法。Using a Cu anode with a low Ag content as a raw material, electrolytic treatment is performed using an organic solvent bath of cuprous chloride and alkylpyridinium halide with a low Ag content as an electrolytic bath, and the resulting cathode Cu is dissolved in a vacuum. , or cathode Cu
A method for producing high-purity copper, which is characterized by subjecting it to oxidation treatment and reduction treatment, and then melting it in a vacuum.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12176989A JPH02301586A (en) | 1989-05-16 | 1989-05-16 | Production of high-purity copper |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12176989A JPH02301586A (en) | 1989-05-16 | 1989-05-16 | Production of high-purity copper |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH02301586A true JPH02301586A (en) | 1990-12-13 |
Family
ID=14819432
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP12176989A Pending JPH02301586A (en) | 1989-05-16 | 1989-05-16 | Production of high-purity copper |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH02301586A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0882813A1 (en) * | 1997-06-02 | 1998-12-09 | Japan Energy Corporation | High-purity copper sputtering targets and thin films |
-
1989
- 1989-05-16 JP JP12176989A patent/JPH02301586A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0882813A1 (en) * | 1997-06-02 | 1998-12-09 | Japan Energy Corporation | High-purity copper sputtering targets and thin films |
| US6451135B1 (en) | 1997-06-02 | 2002-09-17 | Japan Energy Corporation | High-purity copper sputtering targets and thin films |
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