JP2006035777A

JP2006035777A - Mold, molded piece by using the same, manufacturing method for sputtering target and sputtering target

Info

Publication number: JP2006035777A
Application number: JP2004222485A
Authority: JP
Inventors: Kenichi Ito; 謙一伊藤; Tetsuo Shibutami; 哲夫渋田見
Original assignee: Tosoh Corp
Current assignee: Tosoh Corp
Priority date: 2004-07-29
Filing date: 2004-07-29
Publication date: 2006-02-09
Anticipated expiration: 2024-07-29
Also published as: JP4830276B2

Abstract

<P>PROBLEM TO BE SOLVED: To provide a mold capable of obtaining a large sized molded piece free from breakage or cracks and excellent in shape accuracy using a cold isostatic press and without performing preforming, thereby to provide a sputtering target of high quality and at a low cost. <P>SOLUTION: The mold for the cold isostatic press is constituted by a sheet material which does not become deformed even under pressurization by the cold isostatic press and a member having a structure which easily shrinks or becomes deformed during pressurization but does not generate repulsive force during decompression or by a member constituted by such a material. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

本発明は、大型でかつ高密度を要求されるスパッタリングターゲットの製造法に関し、特に冷間静水圧プレスを用いて成形体を製造する際に用いられる成形型、それを用いた成形体及びスパッタリングターゲットの製造方法並びにスパッタリングターゲットに関する。 The present invention relates to a method for producing a sputtering target that is large and requires a high density, and in particular, a molding die used when producing a molded body using a cold isostatic press, a molded body using the same, and a sputtering target. The present invention relates to a manufacturing method and a sputtering target.

スパッタリング法は、大面積化が容易でかつ高性能の膜が得られる成膜法であることから、様々な分野の各デバイスの作製に広く用いられている。例えば、液晶ディスプレイやプラズマディスプレイに代表されるフラットパネルディスプレイ分野では、近年、テレビ用途への展開が急速に進み、パネルサイズが大型化すると共に、低コスト化を目的として１枚のマザーガラスから複数のパネルを作製するために、ガラス基板のサイズが大型化している。その結果、成膜に使用されるスパッタリングターゲットも大型化している。 Since the sputtering method is a film forming method that can easily increase the area and obtain a high-performance film, it is widely used for manufacturing devices in various fields. For example, in the flat panel display field represented by a liquid crystal display and a plasma display, in recent years, the development for television applications has rapidly progressed, and the panel size has been increased, and a plurality of pieces from a single mother glass have been developed for the purpose of reducing costs. In order to produce the panel, the size of the glass substrate is increased. As a result, the sputtering target used for film formation is also enlarged.

これらのフラットパネルディスプレイ用表示電極としては、ＩＴＯ（ＩｎｄｉｕｍＴｉｎＯｘｉｄｅ）薄膜が、高導電性、高透過率といった特徴を有し、更に微細加工も行なえることから幅広く使用されている。このＩＴＯ薄膜をスパッタリング法により製造する際に用いるスパッタリングターゲットには、金属インジウムおよび金属スズからなる合金ターゲット（ＩＴターゲット）、或いは酸化インジウムと酸化スズからなる複合酸化物ターゲット（ＩＴＯターゲット）がある。しかしＩＴターゲットに比べ、ＩＴＯターゲットでは得られる膜の抵抗値および透過率の経時変化が少なく、成膜条件の制御が容易であるため、スパッタリング法によるＩＴＯ薄膜の成膜ではＩＴＯターゲットを用いる方法が主流となっている。 As display electrodes for these flat panel displays, ITO (Indium Tin Oxide) thin films are widely used because they have characteristics such as high conductivity and high transmittance and can be finely processed. Sputtering targets used when manufacturing this ITO thin film by sputtering include an alloy target (IT target) made of metal indium and metal tin, or a composite oxide target (ITO target) made of indium oxide and tin oxide. However, the ITO target has less change over time in the resistance and transmittance of the film obtained than the IT target, and the film formation conditions can be easily controlled. It has become mainstream.

しかし、ＩＴＯターゲットをアルゴンガスと酸素ガスとの混合ガス雰囲気中で連続してスパッタリングした場合、積算スパッタリング時間の増加と共にターゲット表面にはノジュールと呼ばれる黒色の付着物が析出する。インジウムの低級酸化物と考えられているこの黒色の付着物は、ターゲットのエロージョン部の周囲に析出するため、スパッタリング時の異常放電の原因となりやすく、またそれ自身が異物（パーティクル）の発生源となることが知られており、パーティクルによる歩留まり低下が、特に近年、低価格化が進んだ液晶ディスプレイなどでは大きな問題となっている。このノジュール低減のためには、ＩＴＯターゲットの高密度化が有効であることが知られている。 However, when the ITO target is continuously sputtered in a mixed gas atmosphere of argon gas and oxygen gas, black deposits called nodules are deposited on the surface of the target as the integrated sputtering time increases. This black deposit, which is considered to be a lower oxide of indium, is deposited around the erosion part of the target, so it tends to cause abnormal discharge during sputtering, and itself is a source of foreign matter (particles). It is known that the decrease in yield due to particles has become a big problem particularly in liquid crystal displays and the like whose prices have been lowered in recent years. It is known that increasing the density of the ITO target is effective for reducing the nodules.

このような高密度な焼結体を得るための成形体の作製方法としては、１次成形として、金型を用いた乾式プレス成形法や鋳込み成形法により成形体を作製した後、冷間静水圧プレスによる高圧力での２次成形を行う２段階処理が必要であった（例えば、特許文献１、２参照）。さらに、１次成形に用いる成形方法によって、それに適した前処理工程（造粒、スラリー化など）も必要となり、製造工程が複雑となるため、コストが高くなる要因であった。 As a method of producing a molded body for obtaining such a high-density sintered body, as a primary molding, after forming a molded body by a dry press molding method using a mold or a casting molding method, A two-stage process for performing secondary forming at a high pressure by a hydraulic press is necessary (see, for example, Patent Documents 1 and 2). Furthermore, depending on the molding method used for the primary molding, a pretreatment process (granulation, slurrying, etc.) suitable for the molding method is required, which complicates the manufacturing process, which increases the cost.

このような製造方法に対して、特許文献３には、１次成形なしにゴム型に粉末を充填して、冷間静水圧プレスにて直接高圧成形する方法も報告されている。しかし、このような方法で成形する場合、肉厚のゴム型で構成されているために、加圧時には、曲げ応力が発生して中央部が大きく変形する。このため、得られる成形体は面方向における中央部の厚みが端部よりも小さくなるため、成形体の断面形状が鼓状となり、形状精度の悪い成形体しか得られなかった。さらに、この方法では、高圧加圧後の減圧過程でゴム型は自身の弾性による復元力により、最終的に加圧前の状態にまで復元するが、成形体は収縮したままであるために、成形体とゴム型の固着などにより、成形体の一部が剥がれたり、あるいは成形体が割れたりする場合があった。 In contrast to such a manufacturing method, Patent Document 3 also reports a method in which a rubber mold is filled with powder without primary molding and directly subjected to high pressure molding by a cold isostatic press. However, when molding by such a method, since it is constituted by a thick rubber mold, a bending stress is generated at the time of pressurization and the central portion is greatly deformed. For this reason, since the thickness of the center part in a surface direction becomes smaller than an edge part, the cross-sectional shape of a molded object becomes a drum shape, and only the molded object with poor shape accuracy was obtained. Furthermore, in this method, the rubber mold is finally restored to the state before pressurization by the restoring force due to its own elasticity in the decompression process after high-pressure pressurization, but the molded body remains contracted. A part of the molded body may be peeled off or the molded body may be cracked due to adhesion between the molded body and the rubber mold.

特許文献４では、このゴム型の復元による成形体の割れに対して、反発弾性値の小さいゴムを用いて、成形体の割れを防止する方法が提案されている。しかし、この方法は成形体へ掛かる応力を小さくし、成形で割れる確立を小さくさせる方法であり、粉末の種類（成形体の強度）によって、あるいは成形体が大型化した場合には、割れが発生する可能性があった。したがって、大型で強度が低い成形体を製造する場合、必ずしも十分な対策ではなかった
また、ゴム型への固着による成形体の割れに対して、特許文献５には、減圧時にほとんど弾性回復しない物質を介在させることで割れの解消が出来ることが報告されている。しかしながら、この方法でも形状精度は依然悪いものであった。 Patent Document 4 proposes a method of preventing cracking of a molded body by using rubber having a small rebound resilience value against cracking of the molded body due to the restoration of the rubber mold. However, this method reduces the stress applied to the molded body and reduces the probability of cracking during molding. Cracking occurs depending on the type of powder (strength of the molded body) or when the molded body becomes larger. There was a possibility. Therefore, when manufacturing a large and low-strength molded body, it was not always a sufficient measure. Also, Patent Document 5 describes a substance that hardly recovers elastically at the time of decompression against cracking of the molded body due to fixation to a rubber mold. It has been reported that cracks can be eliminated by interposing. However, even with this method, the shape accuracy was still poor.

このような形状精度の悪い成形体を用いてターゲットを製造した場合、ターゲットは最終的に所望の製品厚みに仕上げるため、焼結体をフラットな面に研削する必要があるが、その研削量が増加する。したがって、必要となる原料粉末量が増加し、製造コストが高くなる。さらに、研削量が増えることで、研削に必要な加工時間も長くなる。この影響は、サイズが大きくなるほど顕著であり、ターゲットの価格を引き上げる主要な要因である。特に、高価な希少金属であるインジウムから製造されるＩＴＯターゲットにおいては、より多くの原料を必要とすることが、直接ターゲットの価格に影響し、ターゲットが高価なものとなるため、形状精度の良い成形体を得ることが極めて重要であった。 When a target is manufactured using such a molded product with poor shape accuracy, the target must be ground to a flat surface in order to finally finish the target with a desired product thickness. To increase. Therefore, the amount of raw material powder required increases and the manufacturing cost increases. Furthermore, as the amount of grinding increases, the processing time required for grinding becomes longer. This effect becomes more pronounced as the size increases and is a major factor in raising the target price. In particular, in the ITO target manufactured from indium which is an expensive rare metal, the necessity of more raw materials directly affects the price of the target, and the target becomes expensive, so the shape accuracy is good. Obtaining a molded body was extremely important.

特許文献３では、形状精度の改善のために、片面を金属板で構成された型を用いて、冷間静水圧プレスにて直接高圧成形する方法も提案している。しかし、この方法においても、ゴムで構成された面は依然形状精度が悪く、さらに、前記したように、ゴム型と成形体の弾性回復の違いにより、割れや剥離が発生する可能性があった。 Patent Document 3 also proposes a method of directly performing high-pressure forming with a cold isostatic press using a mold having one surface made of a metal plate in order to improve shape accuracy. However, even in this method, the surface made of rubber still has poor shape accuracy, and as described above, cracking and peeling may occur due to the difference in elastic recovery between the rubber mold and the molded body. .

冷間静水圧プレスを用いて、さらに形状精度の良い成形方法として、特許文献６には、粉末を２枚の金属板で挟み、真空パックした後、５〜５０ＭＰaの圧力で冷間静水圧プレスで予備成形した後、再度真空パックを施し冷間静水圧プレスで本成形を行なう方法が報告されている。しかし、この方法では予備成形と本成形と２回の成形が必要であり、従来の２段成形処理における１次成形を冷間静水圧プレスを用いて行っているだけで、１次成形を省略して工程を簡素化する効果はない。さらに、高価な静水圧プレス装置を２回使う必要があり生産性に劣っている。 As a forming method with better shape accuracy using a cold isostatic press, Patent Document 6 discloses that a powder is sandwiched between two metal plates, vacuum packed, and then cold isostatic pressed at a pressure of 5 to 50 MPa. It has been reported that after pre-molding, a vacuum pack is applied again and the main molding is performed by a cold isostatic press. However, this method requires pre-molding, main molding, and two moldings. The primary molding in the conventional two-stage molding process is simply performed using a cold isostatic press, and the primary molding is omitted. Thus, there is no effect of simplifying the process. Furthermore, it is necessary to use an expensive hydrostatic press twice, resulting in poor productivity.

一方、特許文献７では、金型を密閉封入して冷間静水圧プレスに挿入して高圧成形する方法が提案されている。この方法は、基本的に１軸プレスであり、形状精度の優れた成形体が得られるが、このような１軸プレスと同様の型を用いた場合、特に冷間静水圧プレスでは高い圧力で成形されるため、成形圧力が抜けた後の成形体のスプリングバックが大きくなる。したがって、スプリングバックによる成形体の膨張のため、成形体を型から取り出すのが難しくなる。特に、大型の成形や嵩高い粉末の成形の場合、スプリングバックがさらに大きくなるために、脱型の際に成形体が割れてしまう問題があった。さらに、金型の場合、型の自重が重いために、成形体が大型化するほど、その付帯設備も過大なものとなり、生産性を著しく低下させる問題があった。 On the other hand, Patent Document 7 proposes a method in which a mold is hermetically sealed and inserted into a cold isostatic press to perform high pressure molding. This method is basically a uniaxial press, and a molded body with excellent shape accuracy can be obtained. However, when a mold similar to such a uniaxial press is used, particularly in a cold isostatic press, the pressure is high. Since it is molded, the spring back of the molded body after the molding pressure is released increases. Therefore, it becomes difficult to remove the molded body from the mold due to the expansion of the molded body due to the spring back. In particular, in the case of large-scale molding or bulky powder molding, there is a problem that the molded body is cracked during demolding because the springback is further increased. Furthermore, in the case of a mold, since the weight of the mold is heavy, as the size of the molded body increases, the incidental facilities become excessive, and there is a problem that the productivity is remarkably lowered.

このような問題に対して、特許文献８では、樹脂製の組立式型枠及び成形パンチからなる型を用いて、冷間静水圧プレスで成形する方法が提案されている。型枠が分解できることから、型から成形体を取り出すことは容易になる。しかしながら、この方法でもスプリングバックの解消に至っておらず、減圧後、スプリングバックによる成形体の膨張のため、成形体と枠との間に応力がかかり、これによって成形体が割れる可能性があった。特に、ターゲットの大型化のように、厚みは変わらずに面積のみが大きくなる場合、大型化によるスプリングバックの絶対量（膨張量）が大きくなり、成形体と枠との間に大きな応力が発生するが、厚みは薄いためにこの応力に成形体が耐えられずに、割れてしまうという問題があった。 In order to deal with such a problem, Patent Document 8 proposes a method of forming by a cold isostatic press using a mold including a resin-made assembly form and a forming punch. Since the mold can be disassembled, it is easy to take out the molded body from the mold. However, even with this method, the springback has not been eliminated, and after decompression, the molded body is expanded by the springback, so that stress is applied between the molded body and the frame, which may break the molded body. . In particular, when the target area is large without increasing the thickness, such as an increase in the size of the target, the absolute amount (expansion amount) of the springback increases due to the increase in size, and a large stress is generated between the molded body and the frame. However, since the thickness is thin, there is a problem that the molded body cannot withstand this stress and is cracked.

特開２０００−１４４３９３号公報JP 2000-144393 A 特開平０５−３１１４２８号公報Japanese Patent Laid-Open No. 05-311428 特開２００３−００３２５７号公報JP 2003-003257 A 特開平０９―０５７４９５号公報Japanese Patent Laid-Open No. 09-057495 特開平０６−１００９０３号公報Japanese Patent Laid-Open No. 06-100903 特開平０９−００３６３６号公報JP 09-003636 A 特開平０５−２８７３１５号公報JP 05-287315 A 特公平０８−００９１２０号公報Japanese Patent Publication No. 08-009120

本発明は、高密度焼結体を得るための成形体の製造方法において、予備成形を必要とせずに冷間静水圧プレスを用いて、割れ・クラックが発生することがなく、形状精度の優れた大型の成形体を得ることが出きる成形型を提供することにより、高品質で低コストなスパッタリングターゲットを提供するものである。 The present invention is a method for producing a molded body for obtaining a high-density sintered body, using a cold isostatic press without the need for preforming, and having excellent shape accuracy without cracks and cracks. A high-quality and low-cost sputtering target is provided by providing a mold capable of obtaining a large-sized molded body.

本発明者らは、冷間静水圧プレスを用いて原料粉末から直接板状成形体を製造する際に使用する成形型の構造及び材質について、鋭意検討を重ねた結果、成形体の形状精度を向上させるために、２枚の板材で挟んで成形する際に発生するスプリングバック等の応力を解消する方法を見出し、本発明を完成するに至った。 As a result of intensive studies on the structure and material of the mold used when manufacturing a plate-shaped molded body directly from raw powder using a cold isostatic press, the present inventors have improved the shape accuracy of the molded body. In order to improve, the present inventors have found a method of eliminating stress such as springback that occurs when molding is performed by sandwiching two plate materials, and the present invention has been completed.

すなわち、本発明は、冷間静水圧プレスでの加圧においても変形を起こさない板材と、加圧時に容易に収縮または変形するが、減圧時に復元力を発生させない構造を有する部材またはそのような材料で構成された部材とで構成されていることを特徴とする冷間静水圧プレス用の成形型、それを用いた成形体及びスパッタリングターゲットの製造方法並びにその方法で得られたスパッタリングターゲットに関する。 That is, the present invention relates to a plate material that does not deform even in pressurization in a cold isostatic press, a member having a structure that easily contracts or deforms during pressurization but does not generate a restoring force during decompression, or such a member The present invention relates to a mold for cold isostatic pressing, a molded body using the same, a method for producing a sputtering target, and a sputtering target obtained by the method.

本発明の成形型は、成形型内に充填した原料粉末を、冷間静水圧プレスにより成形して板状の成形体を製造するための成形型であって、前記板状の成形体の一方の板面に当接する第一の部材と、前記成形体の他方の板面に当接する第二の部材と、これらの第一及び第二の部材とともに、原料粉末充填用の空隙を形成する側部部材とを有し、前記第一及び第二の部材が、冷間静水圧プレスでの加圧においても実質的に変形を起こさない部材からなるとともに、前記側部部材が、冷間静水圧プレスでの加圧時には容易に収縮又は変形するが、減圧時には実質的に復元力を発生しない構造を有するか、又は、前記側部部材が、冷間静水圧プレスでの加圧時には容易に収縮若しくは変形するが、減圧時には実質的に復元力を発生しない材料により構成されていることを特徴とする冷間静水圧プレス用の成形型である。 The molding die of the present invention is a molding die for producing a plate-shaped molded body by molding the raw material powder filled in the mold by cold isostatic pressing, and one of the plate-shaped molded bodies A first member that comes into contact with the plate surface, a second member that comes into contact with the other plate surface of the molded body, and a side that forms a gap for filling raw material powder together with these first and second members And the first member and the second member are members that do not substantially deform even in pressurization by cold isostatic pressing, and the side member is cold isostatic pressure. It has a structure that is easily shrunk or deformed when pressed with a press, but does not substantially generate a restoring force when depressurized, or the side member is easily shrunk when pressed with a cold isostatic press. Alternatively, it is made of a material that deforms but does not generate a substantial restoring force during decompression. It is cold-forming die for isostatic pressing, characterized in that.

また、本発明の成形型は、成形型内に充填した原料粉末を、冷間静水圧プレスにより成形して板状の成形体を製造するための成形型であって、前記板状の成形体の一方の板面に当接する第一の部材と、前記成形体の他方の板面に当接する第二の部材と、これらの第一及び第二の部材とともに、原料粉末充填用の空隙を形成する側部部材とを有し、前記第一及び第二の部材が、冷間静水圧プレスでの加圧においても実質的に変形を起こさない部材からなるとともに、前記側部部材が、前記第一及び第二の部材の周囲を囲むシート状の部材であり、冷間静水圧プレスでの加圧時には容易に変形するが、減圧時には実質的に復元力を発生しないことを特徴とする冷間静水圧プレス用の成形型である。 The molding die of the present invention is a molding die for producing a plate-shaped molded body by molding the raw material powder filled in the mold by cold isostatic pressing, and the plate-shaped molded body A first member that abuts on one plate surface, a second member that abuts on the other plate surface of the molded body, and a gap for filling raw material powder together with these first and second members The first member and the second member are members that do not substantially deform even in pressurization by cold isostatic pressing, and the side member is the first member. A sheet-like member that surrounds the periphery of the first and second members, and is easily deformed when pressurized by a cold isostatic press, but does not substantially generate a restoring force when decompressed. This is a mold for isostatic pressing.

さらに、本発明の成形型は、成形型内に充填した原料粉末を、冷間静水圧プレスにより成形して板状の成形体を製造するための成形型であって、前記板状の成形体の一方の板面に当接する第一の部材と、前記成形体の他方の板面に当接する第二の部材と、これらの第一及び第二の部材とともに、原料粉末充填用の空隙を形成する側部部材とを有し、前記第一及び第二の部材が、冷間静水圧プレスでの加圧においても実質的に変形を起こさない部材からなるとともに、前記側部部材は、冷間静水圧プレスでの加圧時には容易に収縮又は変形し、減圧時に発生する側部部材の復元力を打消す方向に、型の外部からその復元力以上の力を加えることができる構造を有することを特徴とする冷間静水圧プレス用の成形型であり、具体的には、型の外部からスプリングやゴムバンドを用いてその復元力以上の力を加えることができる構造としたことを特徴とする冷間静水圧プレス用の成形型である。 Further, the molding die of the present invention is a molding die for producing a plate-shaped molded body by molding the raw material powder filled in the mold by a cold isostatic press, and the plate-shaped molded body A first member that abuts on one plate surface, a second member that abuts on the other plate surface of the molded body, and a gap for filling raw material powder together with these first and second members And the first and second members are members that do not substantially deform even in pressurization with a cold isostatic press, and the side members are cold It has a structure that can be easily contracted or deformed during pressurization with an isostatic press, and that a force greater than the restoring force can be applied from the outside of the mold in a direction that cancels the restoring force of the side member that occurs during decompression. This is a mold for cold isostatic pressing characterized by With Luo spring or rubber band which is mold for cold isostatic pressing, characterized in that it has a structure capable of applying the restoring force or a force.

また、本発明の成形型は、成形型内に充填した原料粉末を、冷間静水圧プレスにより成形して板状の成形体を製造するための成形型であって、前記板状の成形体の一方の板面に当接する第一の部材と、前記成形体の他方の板面に当接する第二の部材と、これらの第一及び第二の部材とともに、原料粉末充填用の空隙を形成する側部部材とを有し、前記第一及び第二の部材が、冷間静水圧プレスでの加圧においても実質的に変形を起こさない部材からなるとともに、前記側部部材は、冷間静水圧プレスでの加圧時には、容易に収縮又は変形する材料により構成されているか、又は、容易に収縮又は変形する構造を有し、かつ、減圧時に発生する該側部部材の復元力を打消して、前記板状の成形体の板面と前記第一及び第二の部材とが各々接触した状態を維持する復元力を打消し手段又は構造を有することを特徴とする冷間静水圧プレス用の成形型である。この復元力打消し手段としては、例えば、前記第一及び第二の部材を束ねるゴムバンドや、前記第一の部材と前記第二の部材との間の間隔を狭める方向に力を作用させる弾性体を有するもの、例えば、前記第一の部材と前記第二の部材を挟持するクリップ、前記第一の部材と前記第二の部材を互いに引き寄せるように、これらの部材の間に配設された弦巻バネ、あるいは、第一又は第二の部材の外側に配設されて、第一及び第二の部材を成形体側に押し付けるスプリング等を例示することができる。 The molding die of the present invention is a molding die for producing a plate-shaped molded body by molding the raw material powder filled in the mold by cold isostatic pressing, and the plate-shaped molded body A first member that abuts on one plate surface, a second member that abuts on the other plate surface of the molded body, and a gap for filling raw material powder together with these first and second members And the first and second members are members that do not substantially deform even in pressurization with a cold isostatic press, and the side members are cold When pressurizing with an isostatic press, it is made of a material that easily contracts or deforms, or has a structure that easily contracts or deforms, and cancels the restoring force of the side member that occurs during decompression. Then, the plate surface of the plate-shaped molded body and the first and second members are in contact with each other. A cold-forming die for isostatic pressing, characterized in that it comprises a means or structure cancel a restoring force to maintain the state. As the restoring force canceling means, for example, a rubber band that bundles the first and second members, or an elastic force that applies a force in a direction that narrows the interval between the first member and the second member. A body having a body, for example, a clip that sandwiches the first member and the second member, and the first member and the second member are disposed between these members so as to draw each other. Examples thereof include a helical spring, or a spring that is disposed outside the first or second member and presses the first and second members against the molded body side.

なお、本発明において、減圧時には実質的に復元力を発生しないとは、加圧時に生じた収縮・変形状態からの復元力が、成形体や第一又は第二の部材による重力や、成形体の強度に比べて無視し得る程度に十分に小さなものであることであり、減圧開始から終了後まで、第一及び第二の部材と成形体の板面とが各々接した状態を維持していることである。また、第一及び第二の部材が加圧時においても実質的に変形を起こさないとは、加圧状態において、成形体の板面に要求される平面性を確保できる程度に、第一及び第二の部材に収縮や反りの発生が無いことを意味し、例えば、その成形圧力において第一及び第二の部材の収縮率が２％以下、反り量が２ｍｍ以下であることが好ましい。なお、この第一及び第二の部材の変形は成形体に転写されるために、成形体の長さ方向の収縮率と反り量で確認することができる。また、本発明における板状の成形体の板面とは、板状の成形体の表面を構成する６つの面のうち、最も広い２つの面を意味する。 Note that in the present invention, substantially no restoring force is generated at the time of decompression, the restoring force from the contracted / deformed state generated at the time of pressurization is the gravity of the molded body or the first or second member, or the molded body. It is sufficiently small to be negligible compared to the strength of the first and second members and the plate surface of the molded body are kept in contact with each other from the start to the end of the decompression. It is that you are. Further, the fact that the first and second members are not substantially deformed even during pressurization means that the flatness required for the plate surface of the molded body can be ensured in the pressurized state. This means that the second member does not shrink or warp. For example, it is preferable that the shrinkage rate of the first and second members at the molding pressure is 2% or less and the warp amount is 2 mm or less. In addition, since the deformation of the first and second members is transferred to the molded body, it can be confirmed by the contraction rate and the warpage amount in the length direction of the molded body. In addition, the plate surface of the plate-shaped molded body in the present invention means the widest two surfaces among the six surfaces constituting the surface of the plate-shaped molded body.

本発明の成形体の製造方法は、成形型内に充填した原料粉末を、冷間静水圧プレスにより成形する成形体の製造方法において、上記の成形型を用いて、冷間静水圧プレスにより成形することを特徴とする成形体の製造方法である。 The method for producing a molded body of the present invention is a method for producing a molded body in which a raw material powder filled in a mold is molded by cold isostatic pressing, and is molded by cold isostatic pressing using the above mold. It is the manufacturing method of the molded object characterized by doing.

また、本発明の成形体の製造方法は、成形型内に充填した原料粉末を、冷間静水圧プレスにより成形して板状の成形体を製造する方法であって、前記板状の成形体の一方の板面に当接する第一の部材と、前記成形体の他方の板面に当接する第二の部材と、これらの第一及び第二の部材とともに、原料粉末充填用の空隙を形成する側部部材とを有し、前記第一及び第二の部材が、冷間静水圧プレスでの加圧においても実質的に変形を起こさない部材からなるとともに、前記側部部材は、冷間静水圧プレスでの加圧時には容易に収縮又は変形する材料により構成されているか、又は、容易に収縮又は変形する構造を有する冷間静水圧プレス用の成形型を用い、かつ、減圧時に発生する前記側部部材の復元力を打消す復元力打消し手段を設けて、前記板状の成形体の板面と前記第一及び第二の部材とが各々接触した状態を維持しつつ減圧を行うことを特徴とする成形体の製造方法である。 Further, the method for producing a molded body of the present invention is a method for producing a plate-shaped molded body by molding raw material powder filled in a mold by cold isostatic pressing, and the plate-shaped molded body A first member that abuts on one plate surface, a second member that abuts on the other plate surface of the molded body, and a gap for filling raw material powder together with these first and second members And the first and second members are members that do not substantially deform even in pressurization with a cold isostatic press, and the side members are cold It is made of a material that easily shrinks or deforms when pressurized by an isostatic press, or uses a cold isostatic press mold having a structure that easily shrinks or deforms, and is generated when the pressure is reduced. Providing a restoring force canceling means for canceling the restoring force of the side member, A process for producing a molded article which is characterized in that a reduced pressure while maintaining the state in which the plate-shaped body of the plate surface and the first and second members are in contact, respectively.

本発明のスパッタリングターゲットの製造方法は、原料粉末を成形して得た成形体を焼成して焼結体を作製し、得られた焼結体を整形してターゲット材とするスパッタリングターゲットの製造方法において、前記成形体を、上記の成形型を用いて、冷間静水圧プレスにより成形して得ることを特徴とするスパッタリングターゲットの製造方法である。なお、本発明のスパッタリングターゲットの製造方法は、例えば、原料粉末が、インジウム、スズ、酸素を含む粉末からなる場合やインジウム、亜鉛、酸素を含む粉末からなる場合等に好適に用いることができる。 The method for producing a sputtering target of the present invention is a method for producing a sputtering target in which a molded body obtained by molding a raw material powder is fired to produce a sintered body, and the obtained sintered body is shaped into a target material. In the method for producing a sputtering target, the molded body is obtained by molding by cold isostatic pressing using the molding die described above. In addition, the manufacturing method of the sputtering target of this invention can be used suitably, for example, when raw material powder consists of a powder containing indium, tin, and oxygen, or a powder containing indium, zinc, and oxygen.

また、本発明のスパッタリングターゲットは、原料粉末を成形して得た成形体を焼成して焼結体を作製し、得られた焼結体を整形してターゲット材とするスパッタリングターゲットにおいて、前記成形体が、前記の成形体の製造方法により得られた成形体であることを特徴とするスパッタリングターゲットであり、例えば、前記焼結体が、インジウム、スズ、酸素を含む焼結体やインジウム、亜鉛、酸素を含む焼結体であるスパッタリングターゲットである。 In addition, the sputtering target of the present invention is a sputtering target in which a sintered body is produced by firing a molded body obtained by molding a raw material powder, and the obtained sintered body is shaped as a target material. A sputtering target characterized in that the body is a molded body obtained by the method for producing the molded body, for example, the sintered body is a sintered body containing indium, tin, oxygen, indium, zinc A sputtering target which is a sintered body containing oxygen.

以下、本発明を具体例を用いて詳細に説明する。 Hereinafter, the present invention will be described in detail using specific examples.

本発明に用いられる材料は、特に限定されるものではないが、例えば、ＩＴＯ（ＩｎｄｉｕｍＴｉｎＯｘｉｄｅ）、ＩＺＯ（ＩｎｄｉｕｍＺｉｎｃＯｘｉｄｅ）、ＡＺＯ（ＡｌｕｍｉｎｕｍＺｉｎｃＯｘｉｄｅ）、ＧＺＯ（ＧａｌｌｉｕｍＺｉｎｃＯｘｉｄｅ）、ＢＳＴ（ＢａｒｉｕｍＳｔｒｏｎｔｉｕｍＴｉｔａｎａｔｅ）、ＳＴＯ（ＳｔｒｏｎｔｉｕｍＴｉｔａｎａｔｅ）等を挙げることができる。 Although the material used for this invention is not specifically limited, For example, ITO (Indium Tin Oxide), IZO (Indium Zinc Oxide), AZO (Aluminum Zinc Oxide), GZO (Gallium Zinc Oxide), BST (Barium) (Strontium Titanate), STO (Strontium Titanate), and the like.

本発明のスパッタリングターゲットを構成する焼結体の製造は、原料粉末を必要に応じて混合し、成形、焼成して得られるが、このような原料粉末の混合、成形体の焼成は通常用いられている方法により行うことができる。 Production of the sintered body constituting the sputtering target of the present invention is obtained by mixing raw material powder as necessary, forming and firing, and such mixing of raw material powder and firing of the molded body are usually used. It can be done by the method.

原料粉末の混合は、例えば、ボールミル、ジェットミル、クロスミキサー等で行なう。原料粉末を混合する前に、原料粉末の粉砕及び／又は分級処理を施しておくことが好ましい。こうした粉砕・分級処理を施すことにより原料粉末粒径が微細化し、均一に混合しやすくなるため、焼結体内組成の不均一性によって引き起こされる焼結体の変形・割れや密度むらを防止することが可能となる。また、原料粉末として炭酸塩を用いた場合には、粉末を混合した後に、仮焼して脱炭酸処理を施しても良い。なお、原料粉末として１種類の化合物のみを用いる場合には上記のような混合操作が必要でないことは言うまでもない。 The mixing of the raw material powder is performed by, for example, a ball mill, a jet mill, a cross mixer, or the like. Before mixing the raw material powder, it is preferable to pulverize and / or classify the raw material powder. By carrying out such pulverization / classification treatment, the raw material powder particle size becomes finer and it becomes easier to mix uniformly. Therefore, deformation / cracking and uneven density of the sintered body caused by non-uniformity of the composition within the sintered body are prevented. Is possible. Moreover, when carbonate is used as the raw material powder, after the powder is mixed, it may be calcined and subjected to decarbonation treatment. Needless to say, when only one kind of compound is used as the raw material powder, the above mixing operation is not necessary.

本発明では、冷間静水圧プレスを用いて高い圧力で成形され、かつスプリングバックの解消により割れの発生がないことから、通常、乾式プレス成形方法で行なわれている造粒などといった粉末処理は必ずしも必要としないが、造粒して得られた顆粒あるいは平均粒径が１〜１０μｍの粒状のものを原料として用いることができることはいうまでもない。本発明では、このような粉末処理を必ずしも必要としないことから、成形前の粉末処理工程を簡素化することができる。 In the present invention, since it is molded at a high pressure using a cold isostatic press and there is no generation of cracks due to the elimination of springback, powder processing such as granulation usually performed by a dry press molding method is performed. Needless to say, although it is not always necessary, granules obtained by granulation or granules having an average particle diameter of 1 to 10 μm can be used as a raw material. In the present invention, such powder processing is not necessarily required, and therefore the powder processing step before molding can be simplified.

得られた原料粉末を次に、冷間静水圧プレスを用いて板状の成形体とするが、この際、前記板状の成形体の一方の板面に当接する第一の部材と、前記成形体の他方の板面に当接する第二の部材と、これらの第一及び第二の部材とともに、原料粉末充填用の空隙を形成する側部部材とを有し、前記第一及び第二の部材が、冷間静水圧プレスでの加圧においても実質的に変形を起こさない部材からなるとともに、前記側部部材が、冷間静水圧プレスでの加圧時には容易に収縮又は変形するが、減圧時には実質的に復元力を発生しない構造を有するか、又は、冷間静水圧プレスでの加圧時には容易に収縮又は変形するが、減圧時には実質的に復元力を発生しない材料により構成されている冷間静水圧プレス用の成形型を用いて成形を行う。より具体的には、例えば、冷間静水圧プレスでの加圧においても変形を起こさない上下２枚の板材と、これらの２枚の板材の周囲を囲むシート状の部材とで構成され、冷間静水圧プレスでの加圧時には、前記上下２枚の板材の周囲を囲むシート状の部材が容易に変形するが、減圧時には実質的に復元力を発生しない冷間静水圧プレス用の成形型を用いて成形を行なう。 Next, the obtained raw material powder is formed into a plate-shaped molded body using a cold isostatic press, and at this time, the first member that comes into contact with one plate surface of the plate-shaped molded body, A second member that contacts the other plate surface of the molded body, and a side member that forms a gap for filling the raw material powder together with the first and second members, and the first and second members These members are members that do not substantially deform even when pressed by a cold isostatic press, and the side members easily contract or deform when pressed by a cold isostatic press. It has a structure that does not substantially generate a restoring force at the time of decompression, or is made of a material that easily contracts or deforms when pressurized by a cold isostatic press, but does not substantially generate a restoring force at the time of decompression. Molding is performed using a cold isostatic pressing mold. More specifically, for example, it is composed of two upper and lower plate members that do not deform even in pressurization by a cold isostatic press, and a sheet-like member surrounding the periphery of these two plate members. A mold for cold isostatic pressing that does not substantially generate a restoring force during decompression, although the sheet-like member surrounding the upper and lower two plate members is easily deformed during pressurization in the isostatic press. Molding is performed using

あるいは、前記板状の成形体の一方の板面に当接する第一の部材と、前記成形体の他方の板面に当接する第二の部材と、これらの第一及び第二の部材とともに、原料粉末充填用の空隙を形成する側部部材とを有し、前記第一及び第二の部材が、冷間静水圧プレスでの加圧においても実質的に変形を起こさない部材からなるとともに、前記側部部材は、冷間静水圧プレスでの加圧時には、容易に収縮又は変形する材料により構成されているか、又は、容易に収縮又は変形する構造を有し、かつ、減圧時に発生する該側部部材の復元力を打消して、前記板状の成形体の板面と前記第一及び第二の部材とが各々接触した状態を維持する復元力打消し手段又は構造を有する冷間静水圧プレス用の成形型を用いて成形を行う。この減圧時に発生する側部部材の復元力を打消して、前記板状の成形体の板面と前記第一及び第二の部材とが各々接触した状態を維持する復元力打消し手段としては、例えば、前記第一及び第二の部材を束ねるゴムバンドや、前記第一の部材と前記第二の部材との間の間隔を狭める方向に力を作用させる弾性体を有するもの、例えば、前記第一の部材と前記第二の部材を挟持するクリップ、前記第一の部材と前記第二の部材の各々の外側に配設された板状体を互いに引き寄せるように、これらの板状体の間に装着された弦巻バネ、あるいは、板状体の外側に配設されて、板状体を成形体側に押し付けるスプリング等を例示することができる。なお、冷間静水圧プレス時に上側に配置される第一の部材の上に置かれた重りも復元力打消し手段として使用できる。また、復元力打消し構造としては、例えば、冷間静水圧プレス時に上側に配置される第一の部材による重力が、減圧時に発生する側部部材の復元力より大きくなるようにした構造等を例示することができる。具体的な一例としては、冷間静水圧プレスでの加圧においても変形を起こさない上下２枚の板材と、これらの２枚の板材に挟まれた収縮性のある側部部材とで構成され、冷間静水圧プレスでの加圧時には、前記上下２枚の板材に挟まれた収縮性のある部材からなる側部部材が容易に変形し、かつ、減圧時に発生する側部部材の復元力を、前記上下２枚の板材を束ねるゴムバンドにより、この復元力以上の力を加えることにより打消すように構成した冷間静水圧プレス用の成形型を用いて成形を行う。 Alternatively, together with the first member that contacts one plate surface of the plate-shaped molded body, the second member that contacts the other plate surface of the molded body, and these first and second members, A side member that forms a gap for filling raw material powder, and the first and second members are made of a member that does not substantially deform even in pressurization in a cold isostatic press, The side member is made of a material that easily contracts or deforms when pressed by a cold isostatic press, or has a structure that easily contracts or deforms, and is generated when the pressure is reduced. Cold static having a restoring force canceling means or structure that cancels the restoring force of the side member and maintains the state in which the plate surface of the plate-shaped molded body and the first and second members are in contact with each other Molding is performed using a mold for a hydraulic press. As a restoring force canceling means for canceling the restoring force of the side member generated at the time of decompression and maintaining the state where the plate surface of the plate-shaped molded body and the first and second members are in contact with each other, For example, a rubber band that bundles the first member and the second member, or an elastic body that applies a force in a direction that narrows the interval between the first member and the second member, Clips sandwiching the first member and the second member, and the plate-like bodies arranged on the outside of each of the first member and the second member are drawn to each other. Examples thereof include a string spring mounted between them, or a spring disposed outside the plate-like body and pressing the plate-like body against the molded body side. A weight placed on the first member disposed on the upper side during the cold isostatic pressing can also be used as the restoring force canceling means. Further, as the restoring force canceling structure, for example, a structure in which the gravity due to the first member arranged on the upper side during cold isostatic pressing is larger than the restoring force of the side member generated at the time of decompression, etc. It can be illustrated. As a specific example, it is composed of two upper and lower plate members that are not deformed even in pressurization by a cold isostatic press, and a shrinkable side member sandwiched between these two plate members. The side member made of a contractible member sandwiched between the two upper and lower plate members is easily deformed during the pressurization by the cold isostatic press, and the restoring force of the side member generated at the time of pressure reduction Is molded by using a cold isostatic pressing mold configured so as to be canceled out by applying a force greater than the restoring force by means of a rubber band that bundles the two upper and lower plates.

このような成形型を用いて成形を行なうことにより、形状精度に優れ、かつ割れやクラックの無い大型の成形体を得ることが可能となる。 By performing molding using such a mold, it is possible to obtain a large molded body that is excellent in shape accuracy and free from cracks and cracks.

さらに、成形型内に充填した原料粉末を、冷間静水圧プレスにより成形して板状の成形体を製造する方法であって、前記板状の成形体の一方の板面に当接する第一の部材と、前記成形体の他方の板面に当接する第二の部材と、これらの第一及び第二の部材とともに、原料粉末充填用の空隙を形成する側部部材とを有し、前記第一及び第二の部材が、冷間静水圧プレスでの加圧においても実質的に変形を起こさない部材からなるとともに、前記側部部材は、冷間静水圧プレスでの加圧時には容易に収縮又は変形する材料により構成されているか、又は、容易に収縮又は変形する構造を有する冷間静水圧プレス用の成形型を用い、かつ、復元力打消し手段により、前記側部部材の減圧時の復元力を打消して、前記板状の成形体の板面と前記第一及び第二の部材とが各々接触した状態を維持しつつ減圧を行うことによっても、形状精度に優れ、かつ割れやクラックの無い大型の成形体を得ることが可能となる。すなわち、冷間静水圧プレスでの加圧においても変形を起こさない上下２枚の板材と、これらの２枚の板材に挟まれた収縮性のある側部部材とで構成され、冷間静水圧プレスでの加圧時には、前記上下２枚の板材に挟まれた収縮性のある部材からなる側部部材が容易に変形し、かつ、復元力打消し手段を設けて、減圧時に発生する側部部材の復元力を打消す方向に、型の外部からその復元力以上の力を加えることにより、前記板状の成形体の板面と前記第一及び第二の部材とが各々接触した状態を維持しつつ減圧を行うことによっても、形状精度に優れ、かつ割れやクラックの無い大型の成形体を得ることが可能となる。この復元力打消し手段としては、例えば、前記第一及び第二の部材を束ねるゴムバンドや、前記第一の部材と前記第二の部材との間の間隔を狭める方向に力を作用させる弾性体を有するもの、例えば、前記第一の部材と前記第二の部材を挟持するクリップ、前記第一の部材と前記第二の部材の各々の外側に配設された板状体を互いに引き寄せるように、これらの板状体の間に装着された弦巻バネ、あるいは、板状体の外側に配設されて、板状体を成形体側に押し付けるスプリング等を例示することができる。 Further, the raw material powder filled in the mold is molded by a cold isostatic press to produce a plate-shaped molded body, which is in contact with one plate surface of the plate-shaped molded body. A second member that contacts the other plate surface of the molded body, and a side member that forms a gap for filling raw material powder together with the first and second members, The first and second members are members that do not substantially deform even in pressurization with a cold isostatic press, and the side members are easily formed during pressurization with a cold isostatic press. When the side member is decompressed by a cold isostatic pressing mold that is made of a material that shrinks or deforms, or that has a structure that easily shrinks or deforms, and the restoring force canceling means And canceling the restoring force of the plate-like molded body and the first and second plates. By performing the reduced pressure while maintaining the state in which the second member is in contact respectively, excellent shape accuracy, and it is possible to obtain a large-sized molded product having no cracks or crack. That is, it is composed of two upper and lower plate members that are not deformed even in pressurization by a cold isostatic press, and a shrinkable side member sandwiched between these two plate members. When pressurizing with a press, the side member made of a contractible member sandwiched between the two upper and lower plate members is easily deformed, and a restoring force canceling means is provided to generate a side portion generated during decompression. By applying a force equal to or greater than the restoring force from the outside of the mold in a direction to cancel the restoring force of the member, the plate surface of the plate-shaped molded body and the first and second members are in contact with each other. By reducing the pressure while maintaining it, it is possible to obtain a large molded article having excellent shape accuracy and free from cracks and cracks. As the restoring force canceling means, for example, a rubber band that bundles the first and second members, or an elastic force that applies a force in a direction that narrows the interval between the first member and the second member. A body having a body, for example, a clip sandwiching the first member and the second member, and a plate-like body disposed on the outside of each of the first member and the second member are drawn together. In addition, a coiled spring mounted between these plate-like bodies, or a spring that is disposed outside the plate-like body and presses the plate-like body against the molded body side can be exemplified.

本発明の冷間静水圧プレス用の成形型の一例を図１に示す。また、その断面図を図２（ａ）に示す。図中１は冷間静水圧プレスでの加圧においても実質的に変形を起こさない板材からなる第一の部材、２は同じく冷間静水圧プレスでの加圧においても実質的に変形を起こさない板材からなる第二の部材であり、３はこれらの第一及び第二の部材の周囲を囲むシート状の部材からなる側部部材である。そして、これらの第一の部材１、第二の部材２及びシート状部材３で形成される空隙４に原料粉末を充填して冷間静水圧プレスを行い、板状の成形体を得る。なお、シート状部材３の下端は第二の部材２の側面６に固定されていることが、原料粉末の充填を容易にする上で好ましいが、第二の部材２の底面側に折り込んで固定されていても良いし、折り込むだけで特に固定されていなくても良い。また、原料粉末が充填された状態で、シート状部材３は第一の部材１の側面５に固定されていても良いが、図４に断面図で示すように、シート状部材２３（図１の３）３の上端部２６を長くして、第一の部材２１（図１の１）の側面（図１の５）には固定せず、その上面に折り込むようにしても良い。なお、シート状部材２３（図１の３）は第一の部材２１（図１の１）及び第二の部材２２（図１の２）の側面を全て覆う必要はなく、シート状部材２３（図１の３）を固定又は保持できる範囲で、第一の部材２１（図１の１）又は第二の部材２２（図１の２）の側面の厚さ方向の少なくとも一部が覆われていれば良い。 An example of a mold for cold isostatic pressing according to the present invention is shown in FIG. A cross-sectional view thereof is shown in FIG. In the figure, 1 is a first member made of a plate material that does not substantially deform even when pressed by a cold isostatic press, and 2 is substantially deformed even when pressed by a cold isostatic press. Reference numeral 3 denotes a second member made of a non-plate member, and reference numeral 3 denotes a side member made of a sheet-like member surrounding the first and second members. And the raw material powder is filled into the space | gap 4 formed with these 1st member 1, the 2nd member 2, and the sheet-like member 3, and cold isostatic pressing is performed, and a plate-shaped molded object is obtained. The lower end of the sheet-like member 3 is preferably fixed to the side surface 6 of the second member 2 in order to facilitate filling of the raw material powder, but is fixed by being folded to the bottom surface side of the second member 2. It does not have to be fixed by just folding. In addition, the sheet-like member 3 may be fixed to the side surface 5 of the first member 1 in a state in which the raw material powder is filled. However, as shown in a cross-sectional view in FIG. 3) The upper end portion 26 of 3 may be lengthened so that it is not fixed to the side surface (5 of FIG. 1) of the first member 21 (1 of FIG. 1) but may be folded on the upper surface thereof. The sheet-like member 23 (3 in FIG. 1) does not need to cover all the side surfaces of the first member 21 (1 in FIG. 1) and the second member 22 (2 in FIG. 1), and the sheet-like member 23 ( As long as 3) in FIG. 1 can be fixed or held, at least a part of the thickness direction of the side surface of the first member 21 (1 in FIG. 1) or the second member 22 (2 in FIG. 1) is covered. Just do it.

本発明の成形型では、形状精度の良い成形体を得るために、第一の部材及び第二の部材として、例えば、上記のように２枚の板材１、２を用いる。これらの板材としては、冷間静水圧プレスでの加圧時に実質的に変形を生じないものであれば、特に限定はされないが、大型化のためには比重が小さく強度のあるものが好ましく、金属ではアルミニウム、ジュラルミンなど、樹脂ではＭＣナイロン、ＡＢＳ、ベークライトなどの板材が使用可能である。また、これらの２枚の板材１、２の間に、板材１、２と側部部材（シート状部材３）とで囲まれた原料粉末を充填するためのキャビティーを形成するが、この側部部材の材料としては、冷間静水圧プレスでの加圧時に容易に収縮または変形し、減圧時には復元力を実質的に発生することなく、静水圧プレスの圧力を成形体に直接作用させることのできる材料であれば良く、特に限定されないが、例えば、厚さが薄く、柔軟性に富むシート状部材は、厚みが薄いことにより、減圧時に復元力が実質的に発生せず、かつ柔軟性に富むために、冷間静水圧プレスでの加圧時に容易に変形し、本発明の側部部材として好適に使用することができる。 In the molding die of the present invention, in order to obtain a molded body with good shape accuracy, for example, the two plate members 1 and 2 are used as the first member and the second member as described above. These plate materials are not particularly limited as long as they do not substantially deform at the time of pressurization in a cold isostatic press, but those having a small specific gravity and strength are preferred for upsizing, Metals such as aluminum and duralumin can be used, and resins such as MC nylon, ABS, and bakelite can be used. Further, a cavity for filling the raw material powder surrounded by the plate materials 1 and 2 and the side member (sheet-like member 3) is formed between these two plate materials 1 and 2, but this side As the material of the part member, the pressure of the hydrostatic press can be directly applied to the molded body without contracting or deforming easily during the pressurization with the cold isostatic press and without substantially generating a restoring force at the time of depressurization. The material is not particularly limited, but for example, a thin and flexible sheet-like member has a thin thickness, so that a restoring force is not substantially generated during decompression and is flexible. Therefore, it can be easily deformed at the time of pressurization with a cold isostatic press, and can be suitably used as a side member of the present invention.

なお、図１に示す成形型では、成形体の形状は上下の板材１、２の形状と原料粉末の充填量によりほぼ定まるため、シート状部材３には形状を保持するための機能は要求されず、後述のように冷間静水圧プレスでの加圧時には折り畳まれた状態で成形体に接するため、その剛性は小さい方が好ましい。また、冷間静水圧プレスでの加圧時には、シート状部材３にはその両側から同等の圧力が作用するので、結果的に大きな力が加わることはなく、シート状部材３の強度は、原料粉末の充填や搬送等のハンドリング時に破壊しない程度の強度があれば十分である。さらに、冷間静水圧プレスでの加圧時には、充填された原料粉末の厚さの減少量が、水平方向の長さや幅の減少量よりも大きいため、シート状部材３は折り畳まれた状態で成形体に接することになり、伸ばされることはないので大きな延性を有する必要はない。 In the molding die shown in FIG. 1, since the shape of the molded body is substantially determined by the shapes of the upper and lower plates 1 and 2 and the amount of raw material powder, the sheet-like member 3 is required to have a function for maintaining the shape. However, as described later, when pressed by a cold isostatic press, the molded body is in a folded state, and therefore the rigidity is preferably small. In addition, since the same pressure is applied to the sheet-like member 3 from both sides at the time of pressurization by the cold isostatic press, a large force is not applied as a result, and the strength of the sheet-like member 3 It is sufficient if the strength is such that it does not break during handling such as powder filling and conveyance. Furthermore, since the amount of reduction in the thickness of the filled raw material powder is larger than the amount of reduction in the horizontal length and width during pressurization with a cold isostatic press, the sheet-like member 3 is in a folded state. Since it is in contact with the molded body and is not stretched, it is not necessary to have a large ductility.

シート状部材は減圧時に復元力が実質的に発生しないが、特に成形体が大型になった場合、スプリングやゴムバンドなどを用いて型の板材１、２と成形体４が離れないように、若干の外力を加えることが好ましい。このようにすることで、冷間静水圧プレス成形後、型から成形体を取り出すまでのハンドリング時の何らかの衝撃により、板材１、２が一度成形体から離れて、再度成形体に当たることで発生する割れを防止することが出来る。 The sheet-like member does not substantially generate a restoring force at the time of decompression, but in particular, when the molded body becomes large, using a spring, a rubber band, or the like, the mold plate materials 1, 2 and the molded body 4 are not separated. It is preferable to apply a slight external force. By doing in this way, after cold isostatic pressing, the plate materials 1 and 2 are once separated from the molded body due to some impact at the time of handling until the molded body is taken out from the mold, and it occurs when it strikes the molded body again. Cracking can be prevented.

このシート状部材３としては、樹脂、繊維、金属箔などいろいろな材質のものが使用でき、具体的には、ポリエチレン、ポリプロピレン、塩化ビニールなどが使用可能である。特に、空気のみ透過できる繊維質のようなものを用いた場合、粉末充填後に行われる真空パックにおいて、粉末の間に存在する空気を脱気することが出来るために好ましい。このシート状部材３の厚みは、強度や耐久性を考慮すると０．０５〜２ｍｍが好ましい。 The sheet-like member 3 can be made of various materials such as resin, fiber, and metal foil. Specifically, polyethylene, polypropylene, vinyl chloride, and the like can be used. In particular, it is preferable to use a fiber that allows only air to pass through, because the air present between the powders can be degassed in a vacuum pack performed after powder filling. The thickness of the sheet-like member 3 is preferably 0.05 to 2 mm in consideration of strength and durability.

次に、図２（ａ）のように構成された成形型の空隙に原料粉末７を充填し、真空パックを行ない冷間静水圧プレスに投入し高圧成形するが、この時の粉末充填はタッピングや振動等の外力を加えて、最密充填になるように行なうことが好ましい。こうすることで成形時の収縮量が少なくなり、形状精度および成形体密度が高くなる。また、真空パック材であるビニールやアルミ蒸着フィルム製の袋の保護のために、成形型をゴムシートなどにより養生をして真空パックすることが好ましい。 Next, the raw material powder 7 is filled into the gap of the molding die configured as shown in FIG. 2A, vacuum packed, put into a cold isostatic press, and subjected to high pressure molding. It is preferable to apply an external force such as vibration and vibration so as to achieve close packing. By doing so, the amount of shrinkage during molding is reduced, and the shape accuracy and the compact density are increased. In order to protect a bag made of vinyl or aluminum vapor deposited film, which is a vacuum packing material, it is preferable that the mold is cured with a rubber sheet and vacuum packed.

また、本発明の冷間静水圧プレス用の成形型の別の一例の断面図を図５（ａ）に示す。図中３１は冷間静水圧プレスでの加圧においても実質的に変形を起こさない板材からなる第一の部材、３２は同じく冷間静水圧プレスでの加圧においても実質的に変形を起こさない板材からなる第二の部材であり、３３はこれらの第一及び第二の部材に挟まれた収縮性のある部材からなる側部部材である。そして、これらの板材（第一の部材）３１、板材（第二の部材）３２及び収縮性のある部材からなる側部部材３３で形成される空隙３４に原料粉末を充填して冷間静水圧プレスを行う。このとき、収縮性のある部材からなる側部部材３３が減圧時に発生する復元力よりも大きく、外側から成形体側へ向かう力を板材３１、３２に加えながら冷間静水圧プレスを行う。なお、板材３１、３２に外力を加える方法としては、スプリングやゴムバンドなどの使用が上げられる。具体的には、スプリングを用いる場合、図５（ｂ）に示すように、板状の部材であるバックアップ３６で、真空パック材３５を用いて真空パックした後の成形型を挟み込み、スプリング３７でバックアップ３６を成形型に押し付ける。また、成形型にゴムバンドを巻きつけることによっても板材３１、３２に上記の外力を加えることができるが、この場合は、構造が簡単であるために、真空パック前の成形型でも、真空パック後の成形型でも対応可能である。 Moreover, sectional drawing of another example of the shaping | molding die for cold isostatic pressing of this invention is shown to Fig.5 (a). In the figure, reference numeral 31 denotes a first member made of a plate material that does not substantially deform even in pressurization with a cold isostatic press, and 32 also substantially deforms even in pressurization with a cold isostatic press. Reference numeral 33 denotes a second member made of a non-plate member, and reference numeral 33 denotes a side member made of a shrinkable member sandwiched between the first and second members. The raw material powder is filled into the gap 34 formed by the plate member (first member) 31, the plate member (second member) 32, and the side member 33 made of a shrinkable member, and cold isostatic pressure is applied. Press. At this time, cold isostatic pressing is performed while the side member 33 made of a contractible member is larger than the restoring force generated at the time of depressurization and a force from the outside toward the molded body is applied to the plate members 31 and 32. In addition, as a method of applying an external force to the plate members 31 and 32, use of a spring, a rubber band, or the like is raised. Specifically, in the case of using a spring, as shown in FIG. 5 (b), a back-up 36 which is a plate-like member is used to sandwich a mold after vacuum packing using a vacuum packing material 35, and a spring 37 is used. The backup 36 is pressed against the mold. In addition, the above external force can be applied to the plate members 31 and 32 by winding a rubber band around the mold, but in this case, since the structure is simple, the vacuum mold can be used even in the mold before the vacuum pack. Later molds can be used.

この収縮性のある部材からなる側部部材３３としては、復元力が小さいものが好ましく、例えば、体積の大部分が空隙であるスポンジ状のものが利用可能であり、具体的には、シリコンゴムスポンジ、ウレタンフォームなどが上げられる。側部部材の幅は、部材の硬さや成形する成形体の厚みにより決まる部材の高さにより、適宜選択できるが、部材の高さの１／４以上が好ましく、成形型の組み上げや粉末充填の作業性を考慮すると、１０〜３０ｍｍ程度が好ましい。スポンジのように、部材の空隙がすべて連続的に繋がっていれば、真空パック時に部材の空隙の空気は脱気されるため、部材の幅は極めて薄くなり、シート状に近いものとなる。この方法は、シート状の側部部材に比べ、型の組み上げや粉末充填などの一連の成形作業の作業性が極めて良好であるという特徴を有する。しかし、スポンジ状の部材で、特に粉末に接する面に凹凸がある場合、粉末が咬み込み成形体と側部部材が離れなくなるため、粉末に接する面にゴムなどの収縮性のある材料でコーティング処理をする、あるいは、側部部材と粉末の間に、シートやテープなどの界面層を設けるなどの対策をすることが必要である。 As the side member 33 made of the shrinkable member, a member having a small restoring force is preferable. For example, a sponge-like member having a large volume of voids can be used. Sponge, urethane foam, etc. are raised. The width of the side member can be selected as appropriate depending on the height of the member determined by the hardness of the member and the thickness of the molded body to be molded. However, it is preferably at least 1/4 of the height of the member. Considering workability, about 10-30 mm is preferable. If all the gaps of the members are connected continuously like a sponge, the air in the gaps of the members is degassed during vacuum packing, so that the width of the members becomes extremely thin and close to a sheet shape. This method has a feature that the workability of a series of molding operations such as mold assembly and powder filling is extremely good as compared with a sheet-like side member. However, in the case of a sponge-like member, especially when the surface in contact with the powder is uneven, the powder bites the molded body and the side member, so the surface in contact with the powder is coated with a shrinkable material such as rubber. It is necessary to take measures such as providing an interface layer such as a sheet or a tape between the side member and the powder.

このようにして準備された成形型を冷間静水圧プレスに投入し、高圧で成形を行なう。このとき、高圧下では図２（ｂ）に示すように、２枚の板材１、２が静水圧により原料粉末を加圧することで、粉末の内部の圧力が上がり、側面のシート状部材３において、外側から加圧される静水圧と原料粉末内部の圧力が均衡するため、シート状部材３が原料粉末の充填された空隙の内部に過度に入り込んだり、あるいは外側に過度にはみ出したりすることはなく、形状精度の高い成形体８を得ることが出来る。このときの成形圧力としては、高い密度の成形体を得るために、１ｔｏｎ／ｃｍ^２以上が好ましく、より好ましくは２ｔｏｎ／ｃｍ^２以上である。 The mold thus prepared is put into a cold isostatic press and molded at a high pressure. At this time, under high pressure, as shown in FIG. 2 (b), the two plate members 1 and 2 pressurize the raw material powder by hydrostatic pressure, whereby the internal pressure of the powder rises, and the sheet-like member 3 on the side surface In addition, since the hydrostatic pressure pressurized from the outside and the pressure inside the raw material powder are balanced, the sheet-like member 3 may excessively enter the inside of the gap filled with the raw material powder or excessively protrude outside. Therefore, a molded body 8 with high shape accuracy can be obtained. The molding pressure in this case, in order to obtain a molded product of high density, preferably 1 ton / cm ² or more, more preferably 2 ton / cm ² or more.

冷間静水圧プレスにおいては、高圧下で然るべき時間保持された後減圧されるが、このとき図２（ｃ）に示すようにスプリングバックにより成形体８は膨張する。この膨張を不用意に妨げたりすると、成形体に応力が掛かり成形体が割れてしまう原因となる。具体的には、成形体に等方的に圧力が掛かっているときは問題無いが、成形体に掛かる圧力が等方性を失ったとき、すなわち上下面や側面でバランスが崩れた時に、成形体の膨張により割れが発生してしまう。例えば、割れが発生してしまうモデルとしては、図３（ａ）に示すような２枚の板材１１、１２と発泡スチロール製の側部部材１３で構成された成形型が上げられる。このモデルでは、高圧加圧時は図３（ｂ）のように等方的に加圧されている。しかし、減圧時、特に発泡スチロールが弾性回復してしまう数百ｋｇ／ｃｍ^２以下の圧力では、図３（ｃ）のように、冷間静水圧プレスの圧力がまだ残っている段階で、発泡スチロール製の側部部材１３が弾性回復し、これに伴って板材１１、１２と成形体１５との間に隙間が発生する。これにより、成形体１５の上下面を押さえる力は無くなってしまう。一方、成形体１５の側面は発泡スチロールに接して、発泡スチロールの復元力、及び静水圧の残圧の影響を受ける。このようなアンバランスな外圧が成形体に掛かった場合、成形体自体もスプリングバックによる膨張方向へ力が加わっているため、図３（ｄ）に示すように、厚みの横方向にラミネーションクラック１６が発生してしまう。 In the cold isostatic press, the pressure is reduced after being held for a proper time under high pressure, but at this time, the molded body 8 expands due to the spring back as shown in FIG. If this expansion is disturbed carelessly, stress is applied to the molded body, causing the molded body to crack. Specifically, there is no problem when isotropic pressure is applied to the molded body, but when the pressure applied to the molded body loses isotropy, that is, when the balance is lost on the upper and lower surfaces or side surfaces, molding is performed. Cracks occur due to body expansion. For example, as a model in which cracking occurs, a mold composed of two plate members 11 and 12 and a side member 13 made of polystyrene foam as shown in FIG. In this model, isotropic pressure is applied as shown in FIG. However, at the time of decompression, especially at a pressure of several hundred kg / cm ² or less at which the expanded polystyrene is elastically recovered, as shown in FIG. The side member 13 is elastically recovered, and a gap is generated between the plate members 11 and 12 and the molded body 15 accordingly. Thereby, the force which presses the upper and lower surfaces of the molded body 15 is lost. On the other hand, the side surface of the molded body 15 is in contact with the expanded polystyrene and is affected by the restoring force of the expanded polystyrene and the residual pressure of the hydrostatic pressure. When such an unbalanced external pressure is applied to the molded body, a force is applied to the molded body itself in the expansion direction due to the spring back, and therefore, as shown in FIG. Will occur.

これに対して、本発明の一例である図２（ａ）に示した成形型は、２枚の板材１、２と復元力が無く柔軟性に富むシート状部材３で構成されているために、図２（ｃ）に示すように、実質的にゼロ圧まで、常に成形型の上下の板材１、２及びシート状部材３が成形体８の全面に接することで等方的に減圧することができ、アンバランスな外圧が成形体に加わることが無い。同時に、スプリングバックによる成形体の膨張も等方的に緩和することができるため、バインダー等の添加物が入っていない強度の低い成形体や大型でスプリングバックが大きな成形体でも、割れやクラックを発生させることなく、形状精度に優れた成形体の成形が可能となる。このように、冷間静水圧プレスでの減圧時に、側部部材の加圧時の収縮・変形からの復元力が実質的に生じないようにすることにより、減圧時においても、成形体に加わる力を等方的に保つことが可能となり、成形体の割れやクラックの発生を防止することができる。 On the other hand, the molding die shown in FIG. 2A, which is an example of the present invention, is composed of the two plate materials 1 and 2 and the sheet-like member 3 which has no restoring force and is rich in flexibility. As shown in FIG. 2 (c), the upper and lower plate members 1, 2 and the sheet-like member 3 are always isotropically depressurized up to substantially zero pressure by contacting the entire surface of the molded body 8. And no unbalanced external pressure is applied to the molded body. At the same time, the expansion of the molded body due to the spring back can be relaxed isotropically, so cracks and cracks can occur even in low-strength molded bodies that do not contain additives such as binders and large molded bodies with large spring backs. A molded body having excellent shape accuracy can be formed without generating it. In this way, when the pressure is reduced by the cold isostatic press, the restoring force from the contraction / deformation at the time of pressurization of the side member is not substantially generated, so that it is added to the molded body even at the time of pressure reduction. It is possible to keep the force isotropic, and it is possible to prevent the molded body from cracking or cracking.

すなわち、本発明は、冷間静水圧プレスを用いて、２枚の板材により成形することで、１軸プレスのように形状精度の優れた成形体を得ることができ、さらに、減圧時に成形体に対して等方的に圧力を抜くことで、成形体に応力を発生させることなく、スプリングバックを吸収することで割れのない成形体を得ることが出来る成形型である。 That is, according to the present invention, a molded body having excellent shape accuracy can be obtained like a uniaxial press by molding with two plate materials using a cold isostatic press. By removing pressure isotropically, it is a mold that can obtain a molded body without cracks by absorbing the spring back without generating stress in the molded body.

このようにして得られた成形体を焼成炉内で焼成して、焼結体を製造する。焼成温度、昇温速度、降温速度等の条件は、種々の材料によって異なるが、例えばＩＴＯの場合、焼成温度は、酸化スズの酸化インジウム中への固溶が促進される１４００℃〜１６００℃であることが好ましい。１４００℃未満ではＩＴＯとしての焼結が完全でないため、焼結体強度が低く、また１６００℃を超える温度ではＩＴＯ焼結粒子からの酸化インジウムあるいは酸化スズの蒸発が顕著となり、組成ずれ等の問題を引き起こす要因となる。焼成温度までの昇温速度は、成形体の均一な焼結による収縮を考慮すると、２０℃／ｈｒ〜１００℃／ｈｒが好ましい。焼成温度で保持した後の、室温までの降温速度は、１００℃／ｈｒ以下とすることが、焼結体への熱衝撃を緩和し、反り・クラックを防止する点で好ましい。 The molded body thus obtained is fired in a firing furnace to produce a sintered body. Conditions such as the firing temperature, the temperature rise rate, and the temperature fall rate vary depending on various materials. For example, in the case of ITO, the firing temperature is 1400 ° C. to 1600 ° C. at which solid solution of tin oxide in indium oxide is promoted. Preferably there is. Below 1400 ° C, sintering as ITO is not complete, so the strength of the sintered body is low, and at temperatures above 1600 ° C, evaporation of indium oxide or tin oxide from the ITO sintered particles becomes significant, causing problems such as compositional deviations. It becomes a factor causing. The temperature increase rate up to the firing temperature is preferably 20 ° C./hr to 100 ° C./hr in consideration of shrinkage due to uniform sintering of the molded body. The temperature lowering rate to room temperature after being held at the firing temperature is preferably 100 ° C./hr or less from the viewpoint of relaxing thermal shock to the sintered body and preventing warpage and cracking.

以上の方法により製造された焼結体は、形状精度が良好であるので容易に所望の形状に研削加工することができ、容易にスパッタリングターゲットとすることができる。 Since the sintered compact manufactured by the above method has favorable shape accuracy, it can be easily ground into a desired shape and can be easily used as a sputtering target.

本発明によれば、冷間静水圧プレスでの加圧においても変形を起こさない板材と、加圧時に容易に収縮または変形するが、減圧時に復元力を発生させない構造を有する部材またはそのような材料で構成された部材とで構成されている冷間静水圧プレス用成形型を用いて成形を行なうことにより、形状精度に優れ、かつ割れやクラックの無い大型の成形体を得ることが可能となる。特に、本発明の成形型によれば、減圧時に成形体に対して等方的に圧力を抜くことができ、割れの原因となる外圧による応力を発生させることなく、さらにスプリングバックも吸収することが出来るため、成形性の悪い未造粒粉末やバインダー等の添加物が入っていない粉末でも、割れやクラックを発生させること無く成形することが出来る。したがって、成形の前工程である粉末調製工程を大幅に省略でき、製造プロセスの生産性が極めて高くなる。 According to the present invention, a plate member that does not cause deformation even in pressurization in a cold isostatic press, a member that has a structure that easily contracts or deforms during pressurization but does not generate a restoring force during decompression, or such a member By molding using a cold isostatic pressing mold composed of members composed of materials, it is possible to obtain a large compact with excellent shape accuracy and no cracks or cracks Become. In particular, according to the mold of the present invention, it is possible to release pressure isotropically against the molded body at the time of decompression, and further absorb the spring back without generating stress due to external pressure that causes cracking. Therefore, even non-granulated powder with poor moldability and powder containing no additives such as a binder can be molded without causing cracks or cracks. Therefore, the powder preparation step, which is a pre-molding step, can be largely omitted, and the productivity of the manufacturing process becomes extremely high.

以下、本発明を実施例をもって更に詳細に説明するが、本発明はこれに限定されるものではない。 EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to this.

（実施例１）
酸化インジウム粉末および予めジェットミル粉砕処理した酸化スズ粉末を、組成が酸化インジウム：酸化スズ＝９０：１０（ｗｔ％）となるように１６時間乾式ボールミル混合しＩＴＯ混合粉末を作製した。特に、造粒やバインダーの添加などの粉末処理は実施しなかった。 Example 1
The indium oxide powder and the tin oxide powder preliminarily jet milled were mixed by dry ball milling for 16 hours so that the composition was indium oxide: tin oxide = 90: 10 (wt%) to prepare an ITO mixed powder. In particular, powder processing such as granulation and addition of a binder was not performed.

続いて、幅３８０ｍｍ、長さ８１０ｍｍ、厚み１５ｍｍのベークライトの板材を２枚準備し、厚み０．１ｍｍのビニールシートを上記ベークライトの板の周囲を囲む大きさの筒状に加工した。 Subsequently, two sheets of a bakelite plate having a width of 380 mm, a length of 810 mm, and a thickness of 15 mm were prepared, and a 0.1 mm-thick vinyl sheet was processed into a cylindrical shape having a size surrounding the bakelite plate.

図４にその断面図を示すように、ベークライトの板２１、２２と筒状のビニールシート２３を図に示すように、組み上げ、下側の板２２とビニールシート２３を外側からゴムバンド２５で固定した。次いで、上記混合粉末を１１ｋｇ型内に入れ、振動テーブルを用いて粉末を充填した。この時の充填した粉末層２４の厚みは約１５ｍｍであった。もう１枚のベークライト板２１を充填した粉末層２４の上にのせ、ビニールシート２３の上端部２６をベークライトの板２１の上に折込み、さらにその上からゴムシートで包んで、ビニール袋に入れ袋内を減圧し真空パックを行なった。 As shown in the cross-sectional view of FIG. 4, the bakelite plates 21 and 22 and the cylindrical vinyl sheet 23 are assembled as shown in the figure, and the lower plate 22 and the vinyl sheet 23 are fixed from the outside with a rubber band 25. did. Next, the mixed powder was placed in an 11 kg mold and filled with powder using a vibration table. The thickness of the filled powder layer 24 at this time was about 15 mm. Put it on the powder layer 24 filled with another bakelite plate 21, fold the upper end portion 26 of the vinyl sheet 23 on the bakelite plate 21, wrap it in a rubber sheet from above, and put it in a plastic bag The inside was decompressed and vacuum packed.

このようにして準備した成形型を冷間静水圧プレスに投入して、３ｔｏｎ／ｃｍ^２の圧力で成形を行なった。得られた成形体を型から取り出し、形状を確認した。側面にビニールシートの形状が転写されていたが、転写されている凹凸形状の深さは１ｍｍ以下であり、３９０ｍｍ×８１０ｍｍ×９ｍｍｔの成形体を得た。この時の厚みの分布は±０．２ｍｍであった。 The mold thus prepared was put into a cold isostatic press and molded at a pressure of 3 ton / cm ² . The obtained molded body was taken out of the mold and the shape was confirmed. The shape of the vinyl sheet was transferred to the side surface, but the depth of the transferred uneven shape was 1 mm or less, and a molded body of 390 mm × 810 mm × 9 mmt was obtained. The thickness distribution at this time was ± 0.2 mm.

上記成形体を酸素フロー雰囲気焼成炉内に設置し、以下の条件で焼成を実施し、焼結体を作製した。 The molded body was placed in an oxygen flow atmosphere firing furnace and fired under the following conditions to produce a sintered body.

（焼成条件）
焼成雰囲気：酸素雰囲気
昇温速度：１００℃／ｈｒ、焼成温度：１６００℃、焼成時間：５ｈｒ
降温速度：１００℃／ｈｒ
得られた焼結体は、３１０ｍｍ×６６５ｍｍ×７．５ｍｍｔのサイズで、その厚み分布は±０．１５ｍｍであった。また、密度を測定したところ、密度９９．７６％の高密度な焼結体であった。密度の測定は、ＪＩＳ−Ｒ１６３４−１９９８に準拠してアルキメデス法で行い、ＩＴＯの真密度として７．１５６ｇ／ｃｍ^３を用いた。 (Baking conditions)
Firing atmosphere: Oxygen atmosphere Temperature rising rate: 100 ° C./hr, Firing temperature: 1600 ° C., Firing time: 5 hr
Temperature drop rate: 100 ° C / hr
The obtained sintered body had a size of 310 mm × 665 mm × 7.5 mmt and a thickness distribution of ± 0.15 mm. Moreover, when the density was measured, it was a high-density sintered body with a density of 99.76%. Density measurements were performed in Archimedes' method in compliance with JIS-R1634-1998, using 7.156g / cm ³ as the true density of the ITO.

得られた焼結体を研削加工して１０１．６ｍｍ×１７７．８ｍｍ×６ｍｍｔのターゲット材を作製し、無酸素銅製のバッキングプレートにインジウム半田により接合してスパッタリングターゲットを作製した。こうして作製されたスパッタリングターゲットを以下のスパッタリング条件で２０ｋＷｈスパッタリングを行った結果、ノジュールの発生やターゲットの割れは認められなかった。
ＤＣ電力：６００Ｗ
スパッタガス：Ａｒ＋Ｏ_２
ガス圧：５ｍＴｏｒｒ
Ｏ_２／Ａｒ：０．１％
比較例１
成形型の側面をビニールシートではなく発泡スチロールで構成した以外は実施例１と同様の方法で、成形体を作製した。この時の成形型の構造を図３（ａ）に示す。発泡スチロールのサイズは、高さ４５ｍｍ、厚さ１５ｍｍ（図３（ａ）中の側部部材１３の高さと幅）である。 The obtained sintered body was ground to produce a target material of 101.6 mm × 177.8 mm × 6 mmt, and joined to an oxygen-free copper backing plate with indium solder to produce a sputtering target. As a result of performing 20 kWh sputtering on the sputtering target thus produced under the following sputtering conditions, no nodules were generated and no target cracking was observed.
DC power: 600W
Sputtering gas: Ar + O ₂
Gas pressure: 5 mTorr
O ₂ / Ar: 0.1%
Comparative Example 1
A molded body was produced in the same manner as in Example 1 except that the side surface of the mold was made of expanded polystyrene instead of a vinyl sheet. The structure of the mold at this time is shown in FIG. The polystyrene foam has a height of 45 mm and a thickness of 15 mm (the height and width of the side member 13 in FIG. 3A).

冷間静水圧プレス終了後に、成形体を取り出そうとしたが、型内で成形体に割れが発生していた。 After the cold isostatic pressing, an attempt was made to take out the molded product, but cracks were generated in the molded product in the mold.

本発明の成形型の一例を模式的に示す斜視図である。It is a perspective view which shows typically an example of the shaping | molding die of this invention. 本発明の成形型の一例を示す断面図である。It is sectional drawing which shows an example of the shaping | molding die of this invention.

（ａ）未加圧時、（ｂ）加圧時、（ｃ）減圧時
従来の成形型の一例を示す断面図である。 (A) When not pressurized, (b) When pressurized, (c) When decompressed
It is sectional drawing which shows an example of the conventional shaping | molding die.

（ａ）未加圧時、（ｂ）加圧時、（ｃ）減圧時、（ｄ）割れの発生した成形体
実施例１で使用した本発明の成形型の概略を示す断面図である。本発明の成形型の他の一例及びその使用方法の一例を示す断面図である。 (A) Unpressed, (b) Pressurized, (c) Depressurized, (d) Cracked molded body
1 is a cross-sectional view showing an outline of a molding die of the present invention used in Example 1. FIG. It is sectional drawing which shows another example of the shaping | molding die of this invention, and an example of the usage method.

（ａ）成形型、（ｂ）復元力打消し手段を併設した使用例 (A) Mold, (b) Usage example with restoring force canceling means

Explanation of symbols

１、１１、２１、３１第一の部材（板材）
２、１２、２２、３２第二の部材（板材）
３、２３側部部材（シート状部材）
１３側部部材（発泡スチロール製）
３３収縮性のある部材からなる側部部材
４、３４原料粉末が充填される空隙
５第一の部材（板材）の側面
６第二の部材（板材）の側面
７、１４、２４充填された原料粉末
８、１５成形体
１６成形体に生じた割れ
２５ゴムバンド
２６シート状部材の上端部
３５真空パック材
３６バックアップ
３７スプリング
1, 11, 21, 31 First member (plate material)
2, 12, 22, 32 Second member (plate material)
3, 23 Side member (sheet-like member)
13 Side member (made of Styrofoam)
33 Side members made of a contractible member 4, 34 Space filled with raw material powder 5 Side surface of first member (plate material) 6 Side surface of second member (plate material) 7, 14, 24 Filled raw material Powders 8 and 15 Molded body 16 Cracks generated in the molded body 25 Rubber band 26 Upper end portion of sheet-like member 35 Vacuum packing material 36 Backup 37 Spring

Claims

A molding die for producing a plate-like molded body by molding the raw material powder filled in a molding die by cold isostatic pressing, wherein the first powder abuts against one plate surface of the plate-shaped molded body One member, a second member that contacts the other plate surface of the molded body, and a side member that forms a gap for filling raw material powder together with the first and second members, The first and second members are made of a member that does not substantially deform even in pressurization with a cold isostatic press, and the side member is easy when pressurizing with a cold isostatic press. A mold for cold isostatic pressing, characterized in that it has a structure that shrinks or deforms but does not substantially generate a restoring force during decompression.

A molding die for producing a plate-like molded body by molding the raw material powder filled in a molding die by cold isostatic pressing, wherein the first powder abuts against one plate surface of the plate-shaped molded body One member, a second member that contacts the other plate surface of the molded body, and a side member that forms a gap for filling raw material powder together with the first and second members, The first and second members are made of a member that does not substantially deform even in pressurization with a cold isostatic press, and the side member is easy when pressurizing with a cold isostatic press. A mold for cold isostatic pressing, characterized in that it is made of a material that shrinks or deforms, but does not substantially generate a restoring force during decompression.

A molding die for producing a plate-like molded body by molding the raw material powder filled in a molding die by cold isostatic pressing, wherein the first powder abuts against one plate surface of the plate-shaped molded body One member, a second member that contacts the other plate surface of the molded body, and a side member that forms a gap for filling raw material powder together with the first and second members, The first and second members are members that do not substantially deform even in pressurization in a cold isostatic press, and the side members are arranged around the first and second members. A mold for cold isostatic pressing, which is a surrounding sheet-like member and is easily deformed when pressurized by a cold isostatic press, but does not substantially generate a restoring force when decompressed.

A molding die for producing a plate-like molded body by molding the raw material powder filled in a molding die by cold isostatic pressing, wherein the first powder abuts against one plate surface of the plate-shaped molded body One member, a second member that contacts the other plate surface of the molded body, and a side member that forms a gap for filling raw material powder together with the first and second members, The first and second members are made of a member that does not substantially deform even in pressurization in a cold isostatic press, and the side member is in pressurization in a cold isostatic press. The plate-shaped molded body is made of a material that easily contracts or deforms, or has a structure that easily contracts or deforms, and cancels the restoring force of the side member that is generated during decompression. Restoring force striking to maintain the state where the plate surface and the first and second members are in contact with each other Cold-forming die for isostatic pressing, characterized in that it comprises a by means or structure.

5. The mold for cold isostatic pressing according to claim 4, wherein the restoring force canceling means is a rubber band for bundling the first and second members.

5. The cooling force according to claim 4, wherein the restoring force canceling means is an elastic body arranged so as to apply a force in a direction of narrowing a distance between the first member and the second member. Mold for hot isostatic pressing.

A method for producing a plate-shaped molded body by molding raw material powder filled in a mold by cold isostatic pressing, wherein the first member is in contact with one plate surface of the plate-shaped molded body A second member that contacts the other plate surface of the molded body, and a side member that forms a gap for filling raw material powder together with the first and second members. And the second member is a member that does not substantially deform even in pressurization in the cold isostatic press, and the side member is easily contracted or pressed during pressurization in the cold isostatic press. A restoring force that is made of a deformable material, or that uses a mold for a cold isostatic press that has a structure that easily contracts or deforms, and that counteracts the restoring force of the side member generated during decompression. Providing a canceling means, the plate surface of the plate-like molded body and the first and Process for producing a molded article which is characterized in that a reduced pressure while maintaining the state in which the second and the member are in contact, respectively.

In the manufacturing method of the molded object which shape | molds the raw material powder with which it filled in the shaping | molding die by cold isostatic pressing, by the cold isostatic pressing using the shaping | molding die of any one of Claims 1-6. A method for producing a molded body, comprising molding.

In the manufacturing method of the sputtering target which makes the sintered compact by baking the molded object obtained by shape | molding raw material powder, and shape | molds the obtained sintered compact and makes it a target material, the said molded object is Claim 7. Alternatively, a method for producing a sputtering target obtained by molding by the method for producing a molded article according to claim 8.

The method for producing a sputtering target according to claim 9, wherein the raw material powder is a powder containing indium, tin, and oxygen.

The method for producing a sputtering target according to claim 9, wherein the raw material powder is a powder containing indium, zinc, and oxygen.

In the sputtering target which makes the sintered compact by baking the molded object obtained by shape | molding raw material powder, and shape | molds the obtained sintered compact and makes it a target material, the said molded object is Claim 7 or Claim. A sputtering target obtained by the method for producing a molded product according to claim 8.

The sputtering target according to claim 12, wherein the sintered body is a sintered body containing indium, tin, and oxygen.

The sputtering target according to claim 12, wherein the sintered body is a sintered body containing indium, zinc, and oxygen.