JPH05271702A - Production of cu-w sintered compact - Google Patents
Production of cu-w sintered compactInfo
- Publication number
- JPH05271702A JPH05271702A JP4068740A JP6874092A JPH05271702A JP H05271702 A JPH05271702 A JP H05271702A JP 4068740 A JP4068740 A JP 4068740A JP 6874092 A JP6874092 A JP 6874092A JP H05271702 A JPH05271702 A JP H05271702A
- Authority
- JP
- Japan
- Prior art keywords
- sintered body
- powder
- density
- mixed powder
- atmosphere
- 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.)
- Withdrawn
Links
- 238000004519 manufacturing process Methods 0.000 title claims description 7
- 238000000034 method Methods 0.000 claims abstract description 17
- 239000011812 mixed powder Substances 0.000 claims abstract description 16
- 239000012298 atmosphere Substances 0.000 claims abstract description 13
- 239000000843 powder Substances 0.000 claims abstract description 13
- 239000000203 mixture Substances 0.000 claims abstract description 10
- 239000002775 capsule Substances 0.000 claims abstract description 9
- 238000000465 moulding Methods 0.000 claims abstract description 5
- 230000006835 compression Effects 0.000 claims abstract description 3
- 238000007906 compression Methods 0.000 claims abstract description 3
- 239000012299 nitrogen atmosphere Substances 0.000 claims description 2
- 238000001513 hot isostatic pressing Methods 0.000 claims 1
- 238000005245 sintering Methods 0.000 abstract description 14
- 238000002156 mixing Methods 0.000 abstract description 5
- 239000002245 particle Substances 0.000 description 5
- 239000000758 substrate Substances 0.000 description 5
- 229910001080 W alloy Inorganic materials 0.000 description 4
- 230000008595 infiltration Effects 0.000 description 4
- 238000001764 infiltration Methods 0.000 description 4
- 239000004065 semiconductor Substances 0.000 description 4
- 229910052802 copper Inorganic materials 0.000 description 3
- 239000013078 crystal Substances 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 229910052721 tungsten Inorganic materials 0.000 description 3
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000007772 electrode material Substances 0.000 description 2
- 238000002844 melting Methods 0.000 description 2
- 230000008018 melting Effects 0.000 description 2
- 239000011148 porous material Substances 0.000 description 2
- 229910018072 Al 2 O 3 Inorganic materials 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 229910052763 palladium Inorganic materials 0.000 description 1
- 238000005204 segregation Methods 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K1/00—Printed circuits
- H05K1/02—Details
- H05K1/09—Use of materials for the conductive, e.g. metallic pattern
- H05K1/092—Dispersed materials, e.g. conductive pastes or inks
Landscapes
- Powder Metallurgy (AREA)
Abstract
(57)【要約】
【目的】 成分配合比を正確に行うことができる混合法
によるＣｕ−Ｗ焼結体を得るに当たって、理想密度に近
い密度を得るための手段の提供。
【構成】 所定の組成割合のＣｕ粉末とＷ粉末との混合
粉末を成形カプセル内に収納したもの、又はその混合粉
末を加圧成形後１０００〜１４００℃で焼結して形成し
た１〜５０％の気孔率を有する中間焼結体を、１０００
以上、不活性雰囲気の１００気圧以上で熱間等方圧縮
（ＨＩＰ）を行なう。これによって、密度が理想密度に
近く、しかもばらつきのない焼結体を得る。(57) [Summary] [Object] To provide a means for obtaining a density close to an ideal density in obtaining a Cu-W sintered body by a mixing method capable of accurately mixing the components. [Structure] A mixed powder of Cu powder and W powder having a predetermined composition ratio is housed in a molding capsule, or 1 to 50% formed by press-molding the mixed powder and sintering at 1000 to 1400 ° C. An intermediate sintered body having a porosity of 1000
As described above, hot isotropic compression (HIP) is performed at 100 atm or more in an inert atmosphere. As a result, a sintered body having a density close to the ideal density and no variation can be obtained.
Description
【０００１】[0001]
【産業上の利用分野】本発明は、半導体基板、ヒートシ
ンク材、電極材等に好適に使用できるＣｕ−Ｗ焼結体の
製造法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a Cu-W sintered body which can be suitably used for semiconductor substrates, heat sink materials, electrode materials and the like.
【０００２】[0002]
【従来の技術】従来、Ｃｕ−Ｗ焼結体の一応用分野とし
て、特公平２−３１８６３号公報にはＷの焼結体中にＣ
ｕを溶浸せしめる半導体基板の製造法が開示されてお
り、このＣｕ−Ｗ焼結体は、熱伝導性も高く、溶浸する
Ｃｕ量を調整することによって熱膨張率の制御が可能
で、また、混合法の場合よりも気密性において優れてい
るとされている。2. Description of the Related Art Conventionally, as an application field of a Cu-W sintered body, Japanese Examined Patent Publication (Kokoku) No. 2-31863 discloses that C is contained in a W sintered body.
A method for manufacturing a semiconductor substrate in which u is infiltrated is disclosed. This Cu-W sintered body has high thermal conductivity, and the coefficient of thermal expansion can be controlled by adjusting the amount of Cu infiltrated. Further, it is said that it is superior in airtightness to the case of the mixing method.
【０００３】[0003]
【発明が解決しようとする課題】しかしながら、Ｗの焼
結スケルトンの空隙中への溶融Ｃｕを溶浸する場合に
は、その溶融Ｃｕの充填量はＷの焼結スケルトンの気孔
率のコントロールが難しく一定になり難く、例えば、半
導体基板，ヒートシンク材用として使用する場合に、熱
膨張率がばらつき、Ａｌ2 Ｏ3 セラミックスなどとの接
合信頼性が低下する問題が生じる。また、かかる溶浸法
によってＣｕ含有量が２０重量％未満のＷ焼結体を製造
する場合には、通常の焼結温度１０００〜１４００℃で
必要な密度をもつ中間焼結体が得られないために、Ｎ
ｉ，Ｆｅ，Ｃｏ，Ｐｄ等の焼結助材を混合粉末に配合し
て、通常の焼結温度で必要な密度をもつ中間焼結体を得
ている。しかし、焼結助材の効果で中間焼結体の密度は
上がるものの目的の組成割合となるための適正温度域が
狭くなり、更に露点等の焼結雰囲気状態にも大きく左右
されるために、組成コントロールが難しく、Ｗ結晶が大
きくなるという問題がある。However, when the molten Cu is infiltrated into the voids of the W sintered skeleton, it is difficult to control the porosity of the W sintered skeleton by adjusting the filling amount of the molten Cu. For example, when used as a semiconductor substrate or a heat sink material, the coefficient of thermal expansion varies and the reliability of bonding with Al 2 O 3 ceramics decreases. Further, when a W sintered body having a Cu content of less than 20% by weight is produced by such an infiltration method, an intermediate sintered body having a required density cannot be obtained at a normal sintering temperature of 1000 to 1400 ° C. For N
A sintering aid such as i, Fe, Co or Pd is mixed with the mixed powder to obtain an intermediate sintered body having a required density at a normal sintering temperature. However, although the density of the intermediate sintered body is increased by the effect of the sintering aid, the appropriate temperature range for achieving the target composition ratio is narrowed, and the sintering atmosphere state such as the dew point is greatly influenced. There is a problem that the composition is difficult to control and the W crystal becomes large.
【０００４】この溶浸法における問題を考えると、正確
に目的の組成割合を有するＣｕ−Ｗ基体を焼結法によっ
て得るには、それぞれ、ＣｕとＷとを所定の割合に混合
した粉末を焼結する普通焼結法の方が優れていると言え
る。Considering the problems in this infiltration method, in order to obtain a Cu-W substrate having the exact composition ratio by the sintering method, powders in which Cu and W are mixed in predetermined ratios are fired respectively. It can be said that the ordinary sintering method of binding is superior.
【０００５】この場合には、この普通焼結法によって得
た焼結体の密度が低く、上記の半導体基板、ヒートシン
ク材、電極材等のように高密度が要求される場合に対応
できないという問題がある。In this case, the density of the sintered body obtained by this ordinary sintering method is low, and it is not possible to cope with the case where high density is required such as the above-mentioned semiconductor substrate, heat sink material and electrode material. There is.
【０００６】本発明によって解決すべき課題は、成分配
合比を正確に行うことができる混合法によってＣｕ−Ｗ
焼結体を得るに当たって、理想密度に近い密度を得るた
めの手段を見出すことにある。[0006] The problem to be solved by the present invention is to use Cu-W by a mixing method which can accurately carry out the component mixing ratio.
In obtaining a sintered body, it is to find a means for obtaining a density close to the ideal density.
【０００７】[0007]
【課題を解決するための手段】本発明は、最終組成割合
のＣｕ粉末とＷ粉末との混合粉末を熱間等方圧縮いわゆ
るＨＩＰを適用することによってその課題を解決した。The present invention has solved the problem by applying hot isotropic compression so-called HIP to a mixed powder of Cu powder and W powder having a final composition ratio.
【０００８】ＨＩＰを適用するに当たっては、混合粉末
を高純度シリカガラス製のような成形用カプセル内に収
納して行う方法と、一旦混合粉末をプレスして予備焼結
し、これをカプセルを使用しない条件の下で行う方法が
任意採用できる。When applying HIP, a method is used in which the mixed powder is stored in a molding capsule such as high-purity silica glass, and the mixed powder is once pressed and pre-sintered, and the capsule is used. The method performed under the condition not to use can be arbitrarily adopted.
【０００９】前者の混合粉末をカプセル内に収納してＨ
ＩＰを行う場合、ＣｕとＷとの混合粉末中のＣｕが２０
重量％以下の場合が比較的適しており、その適用に際し
ては、１０００℃以上、Ａｒ雰囲気１００気圧以上で行
うことが望ましい。温度が１０００℃未満又は雰囲気が
１００気圧未満では、十分な密度が得られない。The former mixed powder is stored in a capsule and H
When performing IP, Cu in the mixed powder of Cu and W is 20
It is relatively suitable if the content is less than or equal to% by weight, and it is desirable that the application is performed at 1000 ° C. or higher and 100 atmospheres or more of Ar atmosphere. If the temperature is lower than 1000 ° C. or the atmosphere is lower than 100 atm, sufficient density cannot be obtained.
【００１０】また、後者の予備焼結後、ＨＩＰを行う場
合には、Ｃｕの配合量が２０重量％以上の比較的多い場
合に適しており、混合粉末を１００〜４００ＭＰａで加
圧成形したのち、Ｈ2 雰囲気中で１０００〜１４００℃
で焼結して、１〜５０％の気孔率を有する中間焼結体を
形成し、この中間焼結体をＡｒ雰囲気又はＮ2 雰囲気
中、１００気圧以上で、１０００℃以上でのＨＩＰ処理
を行う。In the latter case where HIP is carried out after pre-sintering, it is suitable for a relatively large Cu content of 20% by weight or more, and the mixed powder is pressure-molded at 100 to 400 MPa. , 1000~1400 ℃ in an atmosphere of H 2
To form an intermediate sintered body having a porosity of 1 to 50%, and the intermediate sintered body is subjected to HIP treatment at 1000 ° C. or higher in Ar atmosphere or N 2 atmosphere at 100 atm or higher. To do.
【００１１】[0011]
【作用】Ｃｕ−Ｗの混合粉末をカプセル中に収納してＨ
ＩＰ処理を施すことによって、Ｃｕ−Ｗの混合粉末は、
まずＣｕが溶融することにより、収納体の内部は閉鎖孔
となり、表面部は開放孔となるが、閉鎖孔は周囲からの
圧力により、開放孔はカプセルからの圧力により消失し
ていき、その際、Ｗ粒子径は混合時の状態を保ってお
り、その結果、高い密度で且つ細結晶粒を有するＣｕ−
Ｗの焼結体が得られる。Function: The mixed powder of Cu-W is housed in a capsule and H
By performing the IP treatment, the mixed powder of Cu-W becomes
First, by melting Cu, the inside of the container becomes a closed hole and the surface becomes an open hole, but the closed hole disappears due to the pressure from the surroundings and the open hole due to the pressure from the capsule. , W particle size was kept as it was mixed, and as a result, Cu- having high density and fine crystal grains was formed.
A sintered body of W is obtained.
【００１２】また、予備焼結後のＨＩＰ処理を行うに当
たっては、Ｈ2 雰囲気中で１０００〜１４００℃での焼
結を行った中間焼結体で、その気孔率が１０％以下の場
合は、気孔の殆どが閉鎖孔となっている。Further, in performing the HIP treatment after the pre-sintering, when the intermediate sintered body is sintered at 1000 to 1400 ° C. in an H 2 atmosphere and the porosity is 10% or less, Most of the pores are closed pores.
【００１３】また、中間焼結体の気孔率が１０％より大
きい場合は、表面部が開放孔となっているが、ＨＩＰで
の温度が上がりＣｕの融点を超えると、焼結の進行と共
に、Ｃｕが中間焼結体の表面を覆い開放孔が閉鎖される
ので、カプセルの必要はない。When the porosity of the intermediate sintered body is larger than 10%, the surface portion is open, but when the temperature in HIP rises and exceeds the melting point of Cu, the sintering progresses, There is no need for capsules as Cu covers the surface of the intermediate sintered body and the open holes are closed.
【００１４】ＨＩＰ処理過程で温度が１０００℃未満で
は、真空中又は１００気圧未満の雰囲気下にし、１００
０℃以上に昇温してから１００気圧以上に増圧してもよ
い。If the temperature is lower than 1000 ° C. in the HIP process, the temperature is set to 100 ° C. in a vacuum or an atmosphere lower than 100 atm.
The temperature may be raised to 0 ° C. or higher and then increased to 100 atm or higher.
【００１５】[0015]
実施例１ 本発明をＣｕが１０重量％、残がＷであるＣｕ−Ｗ合金
の製造に適用した。Example 1 The present invention was applied to the production of a Cu-W alloy containing 10 wt% Cu and the balance W.
【００１６】平均粒度３μｍのＷ粉末９０重量％と、平
均粒度１０μｍのＣｕ粉末１０重量％との混合粉末を高
純度シリカガラス製カプセルに収納し、１７００℃、Ａ
ｒ雰囲気、１５００気圧の条件でＨＩＰしたところ、密
度１７．１９ｇ／ｃｍ3 （相対密度９９．３％）で均一
組織の焼結体を得た。この方法により、１００個の焼結
体を製造したところ、密度は、１７．１５〜１７．２０
ｇ／ｃｍ3 の範囲に収まった。A mixed powder of 90% by weight of W powder having an average particle size of 3 μm and 10% by weight of Cu powder having an average particle size of 10 μm was placed in a high-purity silica glass capsule and stored at 1700 ° C., A
When HIP was performed in an atmosphere of 1,500 atmospheres, a sintered body having a density of 17.19 g / cm 3 (relative density 99.3%) and a uniform structure was obtained. When 100 sintered bodies were manufactured by this method, the density was 17.15 to 17.20.
It was within the range of g / cm 3 .
【００１７】同様な組成のＣｕ−Ｗ合金を溶浸法により
製造したところ、密度は１６．８０〜１７．１０ｇ／ｃ
ｍ3 とばらつきが大きく、また、焼結助材の添加が必要
なため、Ｗ粒が粗大化した焼結体となった。When a Cu-W alloy having the same composition was produced by the infiltration method, the density was 16.80 to 17.10 g / c.
Since the variation was large with m 3, and the addition of a sintering aid was required, a sintered body with coarse W grains was obtained.
【００１８】実施例２ 本発明をＣｕが３０重量％、残がＷであるＣｕ−Ｗ合金
の製造に適用した。Example 2 The present invention was applied to the production of a Cu-W alloy containing 30% by weight of Cu and the balance of W.
【００１９】平均粒度３μｍのＷ粉末７０重量％と平均
粒度１０μｍのＣｕ粉末３０重量％との混合粉末を１０
０ＭＰａで加圧成形し、Ｈ2 雰囲気中、１４００℃で予
備焼結を行った。その後、１７００℃、Ａｒ雰囲気、１
５００気圧の条件でＨＩＰしたところ、密度１４．１５
ｇ／ｃｍ3 （相対密度９８．９％）で均一組織の焼結体
を得た。この方法により１００個の焼結体を製造したと
ころ、密度のばらつきは１４．１３〜１４．１８ｇ／ｃ
ｍ3 の範囲に収まった。10% by weight of a mixed powder of 70% by weight of W powder having an average particle size of 3 μm and 30% by weight of Cu powder having an average particle size of 10 μm
Pressure molding was performed at 0 MPa, and preliminary sintering was performed at 1400 ° C. in an H 2 atmosphere. After that, 1700 ° C., Ar atmosphere, 1
HIPed under the condition of 500 atm, the density was 14.15
A sintered body having a uniform structure was obtained at g / cm 3 (relative density 98.9%). When 100 sintered bodies were manufactured by this method, the variation in density was 14.13 to 14.18 g / c.
It was within the range of m 3 .
【００２０】同様な組成のＣｕ−Ｗ合金を溶浸法により
製造したところ、密度のばらつきは１３．０７〜１４．
５６ｇ／ｃｍ3 と大きく、Ｃｕ偏析のある組織の焼結体
となった。When a Cu--W alloy having the same composition was manufactured by the infiltration method, the density variation was 13.07 to 14.
The sintered body was as large as 56 g / cm 3 and had a structure with Cu segregation.
【００２１】[0021]
【発明の効果】本発明によって以下の効果を奏する。The present invention has the following effects.
【００２２】（１）混合粉末の調整時に成分コントロー
ルができ、これが最終焼結製品の組成となり成分のばら
つきのないものを得ることができる。(1) The components can be controlled at the time of adjusting the mixed powder, and the composition of the final sintered product can be obtained without variation of the components.
【００２３】（２）Ｃｕ成分の多少に関係なく、Ｃｕが
均一に分布した高い密度の製品を得ることができる。(2) Regardless of the amount of Cu component, it is possible to obtain a high-density product in which Cu is uniformly distributed.
【００２４】（３）結晶粒の成長がない、機械的性質が
優れたＣｕ−Ｗ焼結体とすることができる。(3) A Cu-W sintered body having no crystal grain growth and excellent mechanical properties can be obtained.
【００２５】（４）成分のばらつきがないために、熱膨
張率のコントロールが容易となる。(4) Since there is no variation in the components, it is easy to control the coefficient of thermal expansion.
───────────────────────────────────────────────────── フロントページの続き (72)発明者 松本 実男 福岡県福岡市南区清水２丁目20番31号 日 本タングステン株式会社内 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Mio Matsumoto Nihon Tungsten Co., Ltd. 2-2031 Shimizu, Minami-ku, Fukuoka-shi, Fukuoka
Claims (2)
混合粉末を成形カプセル内に収納して１０００℃以上、
不活性雰囲気の１００気圧以上で熱間等方圧縮を施すＣ
ｕ−Ｗ焼結体の製造法。1. A mixed powder of Cu powder and W powder having a predetermined composition ratio is housed in a molding capsule and heated to 1000 ° C. or higher,
Hot isostatic pressing at 100 atm or more in an inert atmosphere C
Method for manufacturing u-W sintered body.
混合粉末を加圧成形後、１０００℃以上で焼結して、１
〜５０％の気孔率を有する中間焼結体を形成し、この中
間焼結体をＡｒ雰囲気又はＮ2 雰囲気中、１００気圧以
上で、１０００℃以上での熱間等方圧縮処理を行うＣｕ
−Ｗ焼結体の製造法。2. A mixed powder of Cu powder and W powder having a predetermined composition ratio is pressure-molded and then sintered at 1000 ° C. or higher to
Cu which forms an intermediate sintered body having a porosity of ˜50%, and which is subjected to hot isotropic compression treatment at 1000 ° C. or higher at 100 atm or more in Ar atmosphere or N 2 atmosphere.
-A method for producing a W sintered body.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4068740A JPH05271702A (en) | 1992-03-26 | 1992-03-26 | Production of cu-w sintered compact |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4068740A JPH05271702A (en) | 1992-03-26 | 1992-03-26 | Production of cu-w sintered compact |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH05271702A true JPH05271702A (en) | 1993-10-19 |
Family
ID=13382488
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP4068740A Withdrawn JPH05271702A (en) | 1992-03-26 | 1992-03-26 | Production of cu-w sintered compact |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH05271702A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1997001187A1 (en) * | 1995-06-23 | 1997-01-09 | Toho Kinzoku Co., Ltd. | Method of manufacture of material for semiconductor substrate, material for semiconductor substrate, and package for semiconductor |
-
1992
- 1992-03-26 JP JP4068740A patent/JPH05271702A/en not_active Withdrawn
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1997001187A1 (en) * | 1995-06-23 | 1997-01-09 | Toho Kinzoku Co., Ltd. | Method of manufacture of material for semiconductor substrate, material for semiconductor substrate, and package for semiconductor |
| US5905938A (en) * | 1995-06-23 | 1999-05-18 | Toho Kinzoku Co., Ltd. | Method of manufacturing a semiconductor substrate material |
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