JPS62297464A - Production of target for sputtering - Google Patents
Production of target for sputteringInfo
- Publication number
- JPS62297464A JPS62297464A JP13960486A JP13960486A JPS62297464A JP S62297464 A JPS62297464 A JP S62297464A JP 13960486 A JP13960486 A JP 13960486A JP 13960486 A JP13960486 A JP 13960486A JP S62297464 A JPS62297464 A JP S62297464A
- Authority
- JP
- Japan
- Prior art keywords
- ingot
- target
- casting
- mold
- cast
- 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.)
- Granted
Links
- 238000004519 manufacturing process Methods 0.000 title claims description 10
- 238000004544 sputter deposition Methods 0.000 title abstract description 11
- 229910045601 alloy Inorganic materials 0.000 claims abstract description 15
- 239000000956 alloy Substances 0.000 claims abstract description 15
- 238000005266 casting Methods 0.000 claims abstract description 15
- 229910052723 transition metal Inorganic materials 0.000 claims abstract description 9
- 238000009826 distribution Methods 0.000 claims abstract description 7
- 238000000034 method Methods 0.000 claims description 11
- 238000002844 melting Methods 0.000 claims description 5
- 230000008018 melting Effects 0.000 claims description 5
- 238000005477 sputtering target Methods 0.000 claims description 5
- 238000001816 cooling Methods 0.000 abstract description 3
- 230000015572 biosynthetic process Effects 0.000 abstract description 2
- 239000000155 melt Substances 0.000 abstract 1
- 229910052751 metal Inorganic materials 0.000 description 12
- 239000002184 metal Substances 0.000 description 12
- 239000000203 mixture Substances 0.000 description 7
- 239000010408 film Substances 0.000 description 5
- 230000000694 effects Effects 0.000 description 3
- 238000010438 heat treatment Methods 0.000 description 3
- 239000010409 thin film Substances 0.000 description 3
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 2
- 239000011449 brick Substances 0.000 description 2
- 229910052760 oxygen Inorganic materials 0.000 description 2
- 239000001301 oxygen Substances 0.000 description 2
- 229910000967 As alloy Inorganic materials 0.000 description 1
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 229910010293 ceramic material Inorganic materials 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
- KZHJGOXRZJKJNY-UHFFFAOYSA-N dioxosilane;oxo(oxoalumanyloxy)alumane Chemical compound O=[Si]=O.O=[Si]=O.O=[Al]O[Al]=O.O=[Al]O[Al]=O.O=[Al]O[Al]=O KZHJGOXRZJKJNY-UHFFFAOYSA-N 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000012212 insulator Substances 0.000 description 1
- 229910000765 intermetallic Inorganic materials 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 239000006082 mold release agent Substances 0.000 description 1
- 229910052863 mullite Inorganic materials 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 229910052761 rare earth metal Inorganic materials 0.000 description 1
- 150000002910 rare earth metals Chemical class 0.000 description 1
- 230000035939 shock Effects 0.000 description 1
- 238000005245 sintering Methods 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 150000003624 transition metals Chemical class 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】
３、発明の詳細な説明
〔産業上の利用分野〕
本発明はスパッタリング用ターゲットの製造方法に関す
る。Detailed Description of the Invention 3. Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a method of manufacturing a sputtering target.
光磁気用垂直磁化膜作成方法としては、現在主にスパッ
タリングが使用されている。光磁気効果を大きくし、記
録媒体としての実用性を持った薄膜を作成するために、
膜組成は、多元素を含んでいる。このため多元素同時ス
パッタリングが必要となっている。Currently, sputtering is mainly used as a method for producing perpendicularly magnetized films for magneto-optical applications. In order to increase the magneto-optical effect and create a thin film that is practical as a recording medium,
The film composition contains multiple elements. For this reason, multi-element simultaneous sputtering is required.
従来多元素同時スパッタリングの方法としてはターゲッ
トの観点より以下の５種類に分類される。Conventional multi-element simultaneous sputtering methods are classified into the following five types from the viewpoint of targets.
■ 複数のターゲットを同時に使用する多元同時スパッ
タリング法。■ Multi-dimensional simultaneous sputtering method that uses multiple targets simultaneously.
■ ある組成の金属ターゲット上に他の金属チップを置
いたチップオンターゲットを用いる方法。■ A method using a tip-on target, in which a metal tip of one composition is placed on top of another metal tip.
■ 組成元素が違う金属片を機械的に組み合わせた複合
ターゲットを用いる方法。■ A method that uses a composite target that mechanically combines pieces of metal with different compositional elements.
■ 各種金属粉末を焼結した焼結ターゲットを用いる方
法。■ A method using a sintered target made by sintering various metal powders.
■ 各種金属を溶解鋳造した合金ターゲットを用いる方
法。■ A method using an alloy target made by melting and casting various metals.
ここで■を用いる場合、複数の電源の設定が必要となり
、またスパッタリングに伴いターゲット形状の変化によ
り各ターゲットのスパッタリングレートが変化するので
、薄膜の組成分布が変化し制御が困難である。■を用い
る場合チップを置く位置の変化及びスパッタリングに伴
うターゲットまたは、チップの形状変化により薄膜成分
の分布が変化し組成の制御が困難である。■を用いる場
合は、所望組成の正確性、成膜の高速性を得るためには
、複雑な加工を要する欠点がある。■は、金属を微粉末
化する際、表面が酸化し、焼成したターゲ−／ ）には
多量の酸素が含有され、成膜された記録媒体は、■■■
の方法により成膜された記録媒体に比しその記録性能は
劣化する。■は、上記で問題となった膜組成分布の制御
、含有酸素量という観点においてΦ〜■より望ましく、
また量産という観点からしても最も有望とされる方法で
ある。When (2) is used here, it is necessary to set a plurality of power supplies, and the sputtering rate of each target changes due to changes in target shape during sputtering, so the composition distribution of the thin film changes and is difficult to control. When method (2) is used, the distribution of the thin film components changes due to changes in the position where the chip is placed and changes in the shape of the target or chip due to sputtering, making it difficult to control the composition. When using (2), there is a drawback that complicated processing is required in order to obtain the desired composition accuracy and high speed film formation. (2) When the metal is pulverized, the surface is oxidized, the fired target (2) contains a large amount of oxygen, and the film formed on the recording medium is
The recording performance of the recording medium is deteriorated compared to that of the recording medium formed by the method described above. ■ is more desirable than Φ~■ from the viewpoint of controlling the film composition distribution and the amount of oxygen contained, which were the problems mentioned above.
It is also the most promising method from the perspective of mass production.
しかし現在実用化されつつある光磁気記録媒体の組成で
ある希土類、遷移金属系合金を■の合金ターゲットとし
て鋳造した場合、合金は金属間化合物を形成し非常に脆
くなり、鋳塊冷却時の熱歪によりクランクが生じ大面積
のターゲットが形成出来ないという問題点を有する。However, when rare earth and transition metal alloys, which are the composition of magneto-optical recording media that are currently being put into practical use, are cast as alloy targets in (2), the alloys form intermetallic compounds and become extremely brittle. There is a problem in that a crank occurs due to distortion and a target with a large area cannot be formed.
そこで本発明は、このような問題点を解決するもので、
その目的とするところは、脆弱な希土類−遷移金属性合
金を鋳造し、スパッタリング用合金ターゲットを提供す
るところにある。Therefore, the present invention aims to solve these problems.
The purpose is to cast brittle rare earth-transition metal alloys and provide alloy targets for sputtering.
本発明のスパッタリング用ターゲットの製造方法は、希
土類−遷移金属系合金を溶解鋳造し、鋳造した鋳塊をタ
ーゲットの形状に研削する。In the method for manufacturing a sputtering target of the present invention, a rare earth-transition metal alloy is melted and cast, and the cast ingot is ground into the shape of the target.
本発明においては、前記鋳型を２００〜７００℃の温度
範囲で予熱し、鋳造することを特徴とすまた前記鋳型に
おいて、鋳塊が偏平で僅かに研削するとターゲットの形
となるように設計され、また鋳塊の偏平な平面内の温度
分布が均一となるように鋳塊平面中央近傍に接触する鋳
型部に棒状突起物を装着することを特徴とする。The present invention is characterized in that the mold is preheated to a temperature range of 200 to 700° C. and then cast, and the mold is designed so that the ingot is flat and becomes a target shape when slightly ground. Further, a bar-shaped protrusion is attached to the mold portion that contacts the vicinity of the center of the ingot plane so that the temperature distribution within the flat plane of the ingot is uniform.
本発明の前記の製造方法において、予め鋳型を熱するこ
とにより、鋳込み時の熱衝撃が小さくなり、鋳塊全体の
熱歪が小さくなる。また、本発明の前記の構成をした鋳
型を作ると、鋳塊の偏平な平面内の冷却時の温度分布が
均一となり、部分的な熱歪による引張応力が生じ、部分
的なりラックが生ずるということはなくなる。従って本
方法により製造すると、全体的、部分的に鋳塊の熱歪が
小さくなり、タラワクは生じない。In the above manufacturing method of the present invention, by heating the mold in advance, the thermal shock during casting is reduced, and the thermal strain of the entire ingot is reduced. Furthermore, when a mold with the above-described configuration of the present invention is made, the temperature distribution during cooling within the flat plane of the ingot becomes uniform, and tensile stress is generated due to local thermal strain, resulting in partial cracking. That will no longer be the case. Therefore, when manufactured by this method, the thermal strain of the ingot is reduced in whole or in part, and no tarawak occurs.
第１図は、本発明の実施例におけるｉ、η造鋳型である
。鋳造鋳−型は鋳型本体ｌと突起部２と発熱体部５から
構成されている。ｆａｔは正面図、（ｂ）は鋳型部の側
面図、（Ｃ）はヒータ一部の側面図である。使用時にお
いて鋳型部とヒータ一部は、（ａｌの様に組み合わさっ
ているが、図を明快にするために（ト））、ｆｃｌの側
面図においては、別々に示しである。鋳型本体ｌにおい
て、点線は鋳型内壁を示している。FIG. 1 shows an i, η casting mold in an example of the present invention. The casting mold is composed of a mold body l, a projection part 2, and a heating element part 5. fat is a front view, (b) is a side view of the mold part, and (C) is a side view of a part of the heater. In use, the mold part and part of the heater are shown separately in the side view of the fcl (although they are combined as in al, for clarity of the drawing (g)). In the mold body l, the dotted line indicates the mold inner wall.
内壁は、円形ターゲットの形に合わせた円形部２と押し
湯部３から成る偏平形である。鋳型の偏平面の中央には
、ある程度の熱容量を持った突起部４がネジ止めされて
いる。鋳型部と突起部の材質はそれぞれステンレスと銅
であるが高温（約１３００℃）に耐え得る金属・セラミ
フクスならばどのような材質でもよい、また突起部は、
鋳型本体１と一体成型されてもよい、ヒータ一部は、耐
熱レンガ性のホルダー５に発熱体本体を７に示す線に沿
って埋め込む。ヒータ一部中央には円形状の穴をあけ、
突起部４を貫通させている０本鋳型は６に示す偏平な面
に平行な面により左右対称に作られている。また本鋳型
全体は、耐熱レンガによって作られた保温体により保温
されている。The inner wall has a flat shape consisting of a circular part 2 and a riser part 3 that match the shape of the circular target. A protrusion 4 having a certain degree of heat capacity is screwed to the center of the flat surface of the mold. The materials for the mold part and the projections are stainless steel and copper, respectively, but any metal or ceramic material that can withstand high temperatures (approximately 1300℃) may be used.
A part of the heater, which may be integrally molded with the mold body 1, has a heating element body embedded in a heat-resistant brick holder 5 along the line shown at 7. A circular hole is made in the center of part of the heater.
The 0-piece mold through which the protrusion 4 is penetrated is made symmetrically with surfaces parallel to the flat surface shown in 6. Additionally, the entire mold is kept warm by a heat insulator made of heat-resistant bricks.
次に本実施例における工程を説明する。まず本鋳型内部
に離型剤であるムライトを塗布、乾燥後真空溶解炉内に
設置する。次に真空溶解炉内にて金属（希土類−遷移金
属系合金）を真空加熱すると同時に鋳型のヒーターを用
い鋳型を加熱する。Next, the steps in this example will be explained. First, mullite, which is a mold release agent, is applied to the inside of the mold, and after drying, it is placed in a vacuum melting furnace. Next, the metal (rare earth-transition metal alloy) is heated under vacuum in a vacuum melting furnace, and at the same time, the mold is heated using a mold heater.
鋳型の中央部と外縁部には熱電対を設置しておき、鋳型
本体温度を約２００〜７００℃の一定温に制御する。加
熱している金属が溶解したら鋳型に鋳込む、鋳込み温度
は、高すぎると鋳型を溶解してしまうおそれがあり、低
すぎると溶湯の粘度が上がりすぎ、鋳込み性が悪くなり
鋳塊にブローホールを生ずる。従って鋳込み温度は、希
土類−遷移金属系合金に関しては、約１５５０°が良い
。Thermocouples are installed in the center and outer edges of the mold to control the temperature of the mold body to a constant temperature of approximately 200 to 700°C. Once the heated metal has melted, it is poured into a mold.If the pouring temperature is too high, it may melt the mold, and if it is too low, the viscosity of the molten metal will increase too much, making pourability poor and causing blowholes in the ingot. will occur. Therefore, the casting temperature is preferably about 1550° for rare earth-transition metal alloys.
鋳型の予熱に関しては、２００℃以下で鋳造すると、鋳
塊は、複数個に割れて出て来て、また７００℃以上に上
げると金属性の鋳型と溶湯が溶融してしまい、セラミッ
ク性の鋳型の場合においても冷却時間がかかりすぎると
いう欠点を存する。Regarding preheating of the mold, if the ingot is cast at a temperature below 200℃, the ingot will break into multiple pieces, and if the temperature is raised above 700℃, the metal mold and molten metal will melt, causing the ceramic mold to melt. Even in this case, there is a drawback that the cooling time is too long.
従ってかかる温度範囲が決定された。Accordingly, such a temperature range was determined.
棒状突起物を装着しない場合は、鋳塊中央部に熱歪によ
る引っ張り応力が生じ、第２図に示すごとく鋳塊中央部
にひび割れが入る。第２図中１０はターゲット形状をし
た鋳塊、１１は中央部に入ったひび割れである。If the rod-shaped protrusions are not attached, tensile stress due to thermal strain will occur in the center of the ingot, and cracks will appear in the center of the ingot, as shown in FIG. In Fig. 2, numeral 10 indicates a target-shaped ingot, and numeral 11 indicates a crack in the center.
以上述べたように本発明は、希土類−遷移金属系合金を
溶解、鋳造時に、鋳型を予め２００〜７００℃に加熱し
、鋳型中央部に棒状突起部を装着させることにより、ひ
び割れのない鋳塊が得られるという効果を有しそこから
スパッタリング用合金ターゲフトが研削、形成できる。As described above, the present invention provides a method for melting and casting a rare earth-transition metal alloy by preheating the mold to 200 to 700°C and attaching a rod-shaped protrusion to the center of the mold to prevent cracks in the ingot. It has the effect that an alloy target for sputtering can be ground and formed from it.
第１図は本発明の鋳型部とヒータ一部の一実施例を示し
、（ａｌは正面図、山）は鋳型部の側面図、（ｃ）はヒ
ータ一部の側面図である。
第２回は、中央部にひびの入った鋳塊の一例を示す図で
ある。
以 上
（ｂ） （Ｃ）第１図FIG. 1 shows an embodiment of the mold part and part of the heater of the present invention, (al is a front view, crest) is a side view of the mold part, and (c) is a side view of part of the heater. The second drawing shows an example of an ingot with a crack in the center. Above (b) (C) Figure 1
Claims (3)
鋳塊をターゲットの形状に研削することを特徴としたス
パッタリング用ターゲットの製造方法。(1) A method for producing a sputtering target, which comprises melting and casting a rare earth-transition metal alloy and grinding the cast ingot into the shape of the target.
、鋳造することを特徴とする特許請求の範囲第１項記載
のスパッタリング用ターゲットの製造方法。(2) The method for manufacturing a sputtering target according to claim 1, characterized in that the mold is preheated at a temperature range of 200 to 700°C and then cast.
るとターゲットの形となるように設計され、また鋳塊の
偏平な平面内の温度分布が均一となるように鋳塊平面中
央近傍に接触する鋳型部に棒状突起物を装着することを
特徴とする特許請求の範囲第１項又は第２項記載のスパ
ッタリング用ターゲットの製造方法。(3) The mold is designed so that the ingot is flat and will take the shape of a target when slightly ground, and is in contact with the center of the ingot plane so that the temperature distribution within the flat plane of the ingot is uniform. 3. A method of manufacturing a sputtering target according to claim 1 or 2, characterized in that a rod-shaped protrusion is attached to a mold portion.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61139604A JP2568826B2 (en) | 1986-06-16 | 1986-06-16 | Method of producing target for spattering |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61139604A JP2568826B2 (en) | 1986-06-16 | 1986-06-16 | Method of producing target for spattering |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS62297464A true JPS62297464A (en) | 1987-12-24 |
| JP2568826B2 JP2568826B2 (en) | 1997-01-08 |
Family
ID=15249144
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP61139604A Expired - Lifetime JP2568826B2 (en) | 1986-06-16 | 1986-06-16 | Method of producing target for spattering |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2568826B2 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0257682A (en) * | 1988-08-22 | 1990-02-27 | Seiko Epson Corp | Manufacture of sputtering target |
| EP1186682A3 (en) * | 2000-09-05 | 2003-11-26 | W.C. Heraeus GmbH & Co. KG | Cylindrical sputtering target and process for its manufacture |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5914293A (en) * | 1982-07-15 | 1984-01-25 | 株式会社日立製作所 | Temperature controller for induction heating vacuum melting furnace |
| JPS6186061A (en) * | 1984-10-04 | 1986-05-01 | Toshiba Mach Co Ltd | Metallic mold for casting |
| JPS61124566A (en) * | 1984-11-19 | 1986-06-12 | Mitsubishi Metal Corp | Production of al-si alloy target plate material for sputtering |
-
1986
- 1986-06-16 JP JP61139604A patent/JP2568826B2/en not_active Expired - Lifetime
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5914293A (en) * | 1982-07-15 | 1984-01-25 | 株式会社日立製作所 | Temperature controller for induction heating vacuum melting furnace |
| JPS6186061A (en) * | 1984-10-04 | 1986-05-01 | Toshiba Mach Co Ltd | Metallic mold for casting |
| JPS61124566A (en) * | 1984-11-19 | 1986-06-12 | Mitsubishi Metal Corp | Production of al-si alloy target plate material for sputtering |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0257682A (en) * | 1988-08-22 | 1990-02-27 | Seiko Epson Corp | Manufacture of sputtering target |
| EP1186682A3 (en) * | 2000-09-05 | 2003-11-26 | W.C. Heraeus GmbH & Co. KG | Cylindrical sputtering target and process for its manufacture |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2568826B2 (en) | 1997-01-08 |
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