JP2000219572A - Low thermal expansion ceramic and its production - Google Patents
Low thermal expansion ceramic and its productionInfo
- Publication number
- JP2000219572A JP2000219572A JP11022111A JP2211199A JP2000219572A JP 2000219572 A JP2000219572 A JP 2000219572A JP 11022111 A JP11022111 A JP 11022111A JP 2211199 A JP2211199 A JP 2211199A JP 2000219572 A JP2000219572 A JP 2000219572A
- Authority
- JP
- Japan
- Prior art keywords
- thermal expansion
- ceramics
- weight
- raw material
- eucryptite
- 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.)
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- Compositions Of Oxide Ceramics (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、半導体製造工程等
で使用される、露光装置用のＸ−Ｙステージ、静電チャ
ック及びその構造部品、ミラー等の部材に適した軽量低
熱膨張性及び高剛性のセラミックスとその製造方法に関
する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light-weight, low-thermal-expansion and high-temperature material suitable for members such as an XY stage for an exposure apparatus, an electrostatic chuck and its structural parts, and a mirror used in a semiconductor manufacturing process or the like. The present invention relates to a rigid ceramic and a method for producing the same.
【０００２】[0002]
【従来の技術】近年、ＬＳＩ等の半導体電子回路部品の
高集積化に伴い、回路線幅及び回路デザインルールの微
細化が急速に進められ、回路線幅は０．３５μｍから
０．１０μｍまで微細化しつつある。そして、Ｓｉウェ
ハに微細な回路線幅の電子回路を形成するための露光装
置に対して、構造的に高精度及び高い位置精度が要求さ
れるようになってきており、例えば露光装置のＸ−Ｙス
テージにおいては１０ｎｍ未満の位置決め精度が要求さ
れ、製品の品質向上や歩留まり向上、高スループットを
実現する上で、露光装置の位置合わせ誤差の低減が大き
な要素技術として捉えられている。2. Description of the Related Art In recent years, with the increasing integration of semiconductor electronic circuit components such as LSIs, circuit line widths and circuit design rules have been rapidly miniaturized, and circuit line widths have been reduced from 0.35 μm to 0.10 μm. It is becoming. Then, an exposure apparatus for forming an electronic circuit having a fine circuit line width on a Si wafer is required to have a structurally high accuracy and a high positional accuracy. In the Y stage, positioning accuracy of less than 10 nm is required, and reduction of the alignment error of the exposure apparatus is regarded as a major elemental technology in improving the quality of the product, improving the yield, and achieving high throughput.
【０００３】従来、上記したようなＬＳＩ等の半導体電
子回路部品の製造工程において、シリコンウェハに配線
を形成する工程でシリコンウェハを支持又は保持するた
めのサセプタ、真空チャック、静電チャック、絶縁リン
グ及びその他治具等用のセラミックス材料として、比較
的安価で化学的に安定であることからアルミナセラミッ
クスや窒化珪素セラミックスが広く用いられてきた。ま
た、露光装置のＸ−Ｙステージ等の材料としても、従来
よりアルミナセラミックスや窒化珪素セラミックス等が
同様に用いられてきた。Conventionally, in a process of manufacturing a semiconductor electronic circuit component such as an LSI described above, a susceptor, a vacuum chuck, an electrostatic chuck, and an insulating ring for supporting or holding a silicon wafer in a process of forming wiring on the silicon wafer. As ceramic materials for jigs and the like, alumina ceramics and silicon nitride ceramics have been widely used because they are relatively inexpensive and chemically stable. Further, as a material for an XY stage of an exposure apparatus, alumina ceramics, silicon nitride ceramics, and the like have been conventionally used.
【０００４】また、近年、コージェライトセラミックス
の低熱膨張性を利用して、半導体製造用の各種部品及び
治具としてコージェライトセラミックスを使用すること
が提案されている（特開平１−１９１４２２号公報、特
公平６−９７６７５号公報参照）。前記特開平１−１９
１４２２号によれば、Ｘ線露光用のマスク基板に接着す
る補強リングを、ＳｉＯ2 ，インバー等とコージェライ
トセラミックスによって作製することによって、メンブ
レンの応力を制御することが記載されている。また、特
公平６−９７６７５号には、シリコンウェハを載置する
静電チャック用基板としてアルミナセラミックスやコー
ジェライトセラミックスを使用することが開示されてい
る。Further, in recent years, it has been proposed to use cordierite ceramics as various components and jigs for manufacturing semiconductors by utilizing the low thermal expansion properties of cordierite ceramics (Japanese Patent Laid-Open No. 1-1191422, See Japanese Patent Publication No. Hei 6-97675). JP-A-1-19
According to No. 1422, it is described that the stress of the membrane is controlled by fabricating a reinforcing ring bonded to a mask substrate for X-ray exposure using SiO 2 , Invar or the like and cordierite ceramics. Japanese Patent Publication No. 6-97675 discloses the use of alumina ceramics or cordierite ceramics as a substrate for an electrostatic chuck on which a silicon wafer is mounted.
【０００５】また従来、低熱膨張性セラミックスとし
て、コージェライトセラミックスやリチウムアルミノシ
リケートセラミックス（ＬｉＡｌＳｉＯ4 であり、以
下、ＬＡＳとする）が知られている。コージェライトセ
ラミックスについては、コージェライト粉末或いはコー
ジェライトセラミックスを形成するＭｇＯ粉末，Ａｌ2
Ｏ3 粉末，ＳｉＯ2 粉末を配合した原料粉末に、焼結助
剤として希土類酸化物やＣａＯ，ＳｉＯ2 ，ＭｇＯ等を
添加し、所定形状に成形後、１０００〜１４００℃の温
度で焼成することによって製造することが公知である
（特公昭５７−３６２９号公報、特開平２−２２９７６
０号公報参照）。Conventionally, cordierite ceramics and lithium aluminosilicate ceramics (LiAlSiO 4 , hereinafter, referred to as LAS) have been known as low thermal expansion ceramics. Cordierite ceramics include cordierite powder or MgO powder that forms cordierite ceramics, Al 2 powder.
O 3 powder, the raw material powder blended with SiO 2 powder, rare earth oxides or CaO as a sintering aid was added SiO 2, MgO, etc., after molding into a predetermined shape, and baked at a temperature of 1000 to 1400 ° C. (Japanese Patent Publication No. 57-3629, JP-A-2-22976).
No. 0).
【０００６】ＬＡＳ系セラミックスのうち特にβ−スポ
ジュメンについては、天然原料を使用して所定形状に成
形後、１１００〜１４００℃の温度で焼成することによ
って作製されることが知られている（特公昭５３−９６
０５号公報、特公昭５６−１６４０７０号公報参照）。
また、Ａｌ2 Ｏ3 が２５〜７０重量％、ＳｉＯ2 が２５
〜７０重量％、Ｌｉ2 Ｏが１〜５重量％及び不純物が５
重量％以下であるＡｌ2 Ｏ3 ・ＳｉＯ2 ・Ｌｉ2 Ｏ系低
膨張性溶射材料であって、コークス炉の補修材料として
使用され、機械的強度に優れ緻密な溶射膜を形成できる
溶射材料が提案されている（特開昭６３−２５２８０号
公報参照）。[0006] Among the LAS-based ceramics, β-spodumene, in particular, is known to be produced by molding a natural material into a predetermined shape and then firing it at a temperature of 1100 to 1400 ° C. 53-96
No. 05, JP-B-56-164070).
Al 2 O 3 is 25 to 70% by weight, SiO 2 is 25% by weight.
70 wt%, Li 2 O is 1 to 5 wt% and impurities 5
An Al 2 O 3 .SiO 2 .Li 2 O-based low-expansion thermal spray material which is used as a repair material for a coke oven and has a high mechanical strength and can form a dense thermal spray film. It has been proposed (see JP-A-63-25280).
【０００７】[0007]
【発明が解決しようとする課題】半導体製造工程で使用
される各種装置、部品及び治具用として、一般的に用い
られてきたアルミナセラミックス、窒化珪素セラミック
ス等のセラミックスは、金属に較べて軽量で熱膨張率が
小さく、剛性も大きい。それぞれの比重はアルミナセラ
ミックスが３．８、窒化珪素セラミックスが３．２と軽
量である。しかしながら、露光装置の軽量化、またＸ−
Ｙステージ等の駆動系部材の軽量化によるモーター負荷
低減、振動抑制のために、より軽量化が必要とされてき
ている。一方、露光装置の使用温度帯である１０〜４０
℃での熱膨張率は、アルミナセラミックスが約５．０×
１０-6／℃、窒化珪素セラミックスが約１．５×１０-6
／℃であり、回路デザインルールの微細化と共に露光時
の熱変形を軽減するために、より低熱膨張率のものが必
要とされてきている。Ceramics such as alumina ceramics, silicon nitride ceramics and the like, which are generally used for various devices, parts and jigs used in a semiconductor manufacturing process, are lighter in weight than metals. Low coefficient of thermal expansion and high rigidity. The specific gravities are 3.8 for alumina ceramics and 3.2 for silicon nitride ceramics. However, the lightening of the exposure apparatus and the X-
In order to reduce the motor load and reduce the vibration by reducing the weight of the drive system members such as the Y stage, a further reduction in weight is required. On the other hand, the operating temperature range of the exposure apparatus is 10 to 40.
The coefficient of thermal expansion at ℃ is about 5.0 × for alumina ceramics.
10 −6 / ° C., about 1.5 × 10 −6 silicon nitride ceramics
/ ° C., and a circuit having a lower coefficient of thermal expansion is required in order to reduce thermal deformation at the time of exposure together with miniaturization of circuit design rules.
【０００８】これに対して、コージェライト系セラミッ
クスは熱膨張率が０．２×１０-6／℃以下であり、アル
ミナセラミックスや窒化珪素セラミックスに比較して熱
膨張率が低い。しかしながら、剛性の点では、アルミナ
セラミックスが約３５０ＧＰａ（ギガパスカル）、窒化
珪素セラミックスが約３００ＧＰａであるのに対し、多
孔質のコージェライトセラミックスが７０〜９０ＧＰａ
と低い。コージェライトセラミックスを露光装置等に用
いる場合、変形や固有振動数低下に伴う共振発生による
Ｓｉウェハ位置決め時間の増加が懸念される。最近の報
告では、緻密質コージェライトセラミックスとして、比
重２．７、ヤング率１３０〜１４０ＧＰａを有するもの
があり、変形対策や固有振動数の向上について期待され
ている。ただし、比重はアルミナセラミックスや窒化珪
素セラミックスと比較すると小さいものの、露光装置の
重量軽減、部材重量軽減のために、更なる比重低下が望
まれる。On the other hand, cordierite ceramics have a coefficient of thermal expansion of 0.2 × 10 −6 / ° C. or less, and have a lower coefficient of thermal expansion than alumina ceramics and silicon nitride ceramics. However, in terms of rigidity, alumina ceramics are about 350 GPa (gigapascal) and silicon nitride ceramics are about 300 GPa, whereas porous cordierite ceramics are about 70 to 90 GPa.
And low. When cordierite ceramics are used for an exposure apparatus or the like, there is a concern that the Si wafer positioning time may increase due to the occurrence of resonance due to deformation or lowering of the natural frequency. In recent reports, there are dense cordierite ceramics having a specific gravity of 2.7 and a Young's modulus of 130 to 140 GPa, and are expected to prevent deformation and improve the natural frequency. However, although the specific gravity is smaller than that of alumina ceramics or silicon nitride ceramics, further reduction in specific gravity is desired in order to reduce the weight of the exposure apparatus and the weight of members.
【０００９】ＬＡＳ系セラミックスのβ−スポジュメン
については、比重２．０〜２．４、熱膨張率が０．３×
１０-6〜２．７×１０-6／℃、磁器が気孔を有するもの
で−０．３×１０-6〜−１．０×１０-6／℃と低い値を
示すが、ヤング率は６０〜８０ＧＰａと低い。ＬＡＳ系
セラミックスの熱膨張率の低さは、結晶軸方向の異方性
によるものとそれに伴うマイクロクラックの存在がその
要因とされる。マイクロクラックは、結晶軸方向の異方
性の大きさが大きいほどよく見られる。マイクロクラッ
クを抑制する方法は、マイクロクラック発生の臨界粒径
を見極め、臨界粒径内で磁器結晶を制御することとされ
る。Regarding β-spodumene of LAS ceramics, specific gravity is 2.0 to 2.4, and thermal expansion coefficient is 0.3 ×
10 -6 ~2.7 × 10 -6 / ℃ , show -0.3 × 10 -6 ~-1.0 × 10 -6 / ℃ a low value at which porcelain has a porosity, Young's modulus It is as low as 60 to 80 GPa. The low coefficient of thermal expansion of the LAS-based ceramics is due to the anisotropy in the crystal axis direction and the existence of microcracks accompanying the anisotropy. Microcracks are more often seen as the magnitude of the anisotropy in the crystal axis direction increases. The method for suppressing microcracks is to determine the critical grain size at which microcracks occur, and to control the porcelain crystal within the critical grain size.
【００１０】このように、露光装置等用の材料として、
軽量、低熱膨張率、高剛性等の特性が要求されており、
特に金属と比較して軽量及び低熱膨張性を有するセラミ
ックスが望ましく、剛性については組成設計等で対応す
ることが考えられるが、これらの諸特性を共に満足する
セラミックスは従来存在しなかった。As described above, as a material for an exposure apparatus or the like,
Characteristics such as light weight, low coefficient of thermal expansion, and high rigidity are required.
In particular, a ceramic having light weight and low thermal expansion compared to metal is desirable, and it is conceivable that the rigidity can be controlled by a composition design or the like. However, there has been no ceramic that satisfies all of these characteristics.
【００１１】従って、本発明は上記事情を鑑みて完成さ
れたものであり、その目的は、半導体製造工程で使用さ
れる露光装置等の各種装置、部品及び治具の材料として
最適なものであって、軽量で低熱膨張率を有すると共に
高剛性のセラミックスと、その製造方法を提供すること
である。Accordingly, the present invention has been completed in view of the above circumstances, and its object is to provide an optimum material for various apparatuses such as an exposure apparatus used in a semiconductor manufacturing process, parts and jigs. Another object of the present invention is to provide a lightweight ceramic having a low coefficient of thermal expansion and high rigidity, and a method for producing the ceramic.
【００１２】[0012]
【課題を解決するための手段】本発明の低熱膨張性セラ
ミックスは、一般式ＬｉＡｌＳｉＯ4 で表されるβ−ユ
ークリプタイトを９５〜９９重量％、マグネシアを１〜
５重量％を含むことを特徴とする。The low thermal expansion ceramic of the present invention comprises 95-99% by weight of β-eucryptite represented by the general formula LiAlSiO 4 and 1-48% of magnesia.
It is characterized by containing 5% by weight.
【００１３】本発明において、好ましくは、ボイド率が
０．１体積％未満かつ平均ボイド径が２μｍ未満であ
る。In the present invention, the void fraction is preferably less than 0.1% by volume and the average void diameter is less than 2 μm.
【００１４】また、本発明の低熱膨張性セラミックスの
製造方法は、９５〜９９重量％のβ−ユークリプタイト
原料粉末と１〜５重量％のマグネシア原料粉末とを含む
セラミックス原料を酸化雰囲気下で焼結し、その後１１
００〜１２００℃及び１００気圧以上で加圧加焼処理す
ることを特徴とする。Further, the method for producing a low thermal expansion ceramic of the present invention is characterized in that a ceramic raw material containing 95 to 99% by weight of β-eucryptite raw material powder and 1 to 5% by weight of magnesia raw material powder is oxidized in an oxidizing atmosphere. Sintered and then 11
It is characterized by performing pressure baking at 100 to 1200 ° C. and at least 100 atm.
【００１５】本発明の製造方法において、セラミックス
原料を酸化雰囲気下で焼結する際に、相対密度９０％以
上となるように焼結するのが緻密なものを得る上で好ま
しい。In the production method of the present invention, when sintering a ceramic raw material in an oxidizing atmosphere, sintering to a relative density of 90% or more is preferable from the viewpoint of obtaining a dense one.
【００１６】本発明は、低熱膨張性セラミックスの中で
も特に比重の小さいＬＡＳ系セラミックスであって、更
に熱膨張率が低いβ−ユークリプタイトを焼結法、好ま
しくは更に焼結後のホットプレス（加圧加焼）法により
緻密化することでマイクロクラック発生を抑え、低熱膨
率を有しかつ高剛性の材料を得ることができる。The present invention is directed to a method of sintering β-eucryptite, which is a LAS-based ceramic having a low specific gravity and a low coefficient of thermal expansion, among the low thermal expansion ceramics, preferably a hot press after sintering. Densification by the pressure baking method can suppress the occurrence of microcracks and provide a material having a low coefficient of thermal expansion and high rigidity.
【００１７】また、β−ユークリプタイトにマグネシア
を所定量含有させることで、低熱膨張率を維持してβ−
ユークリプタイトを緻密化させることができる。Further, by containing a predetermined amount of magnesia in β-eucryptite, it is possible to maintain a low coefficient of thermal expansion and
The eucryptite can be densified.
【００１８】[0018]
【発明の実施の形態】本発明の低熱膨張性セラミックス
は、軽量低熱膨張特性を有するＬＡＳ系セラミックスで
あって、特にβ−ユークリプタイトとして知られる一般
式ＬｉＡｌＳｉＯ4 で表される複合酸化物から構成され
る。また、この低熱膨張性セラミックス中には、焼結助
剤としてＭｇＯを１〜５重量％含有させる。ＭｇＯ自身
の熱膨張率は、評価温度領域２０〜１０００℃で１３×
１０-6〜１４×１０-6／℃であり、その添加量が５重量
％を越えると液相分の増加により熱膨張率が増大する。
また、添加量が１重量％未満ではβ−ユークリプタイト
が緻密化しない。ＭｇＯ以外の焼結助剤の場合、焼結温
度が上昇し粒成長を伴い、マイクロクラック発生を生じ
る傾向が強い。尚、本発明の低熱膨張性セラミックス
は、β−ユークリプタイト及びＭｇＯ以外に微量の不純
物を含んでいても良い。BEST MODE FOR CARRYING OUT THE INVENTION The low thermal expansion ceramic of the present invention is a LAS-based ceramic having light weight and low thermal expansion characteristics, and in particular, a composite oxide represented by the general formula LiAlSiO 4 known as β-eucryptite. Be composed. The low thermal expansion ceramic contains 1 to 5% by weight of MgO as a sintering aid. The thermal expansion coefficient of MgO itself is 13 × in the evaluation temperature range of 20 to 1000 ° C.
It is 10 -6 to 14 × 10 -6 / ° C., and when the addition amount exceeds 5% by weight, the coefficient of thermal expansion increases due to an increase in the liquid phase.
If the amount is less than 1% by weight, β-eucryptite will not be densified. In the case of a sintering agent other than MgO, the sintering temperature rises, accompanied by grain growth, and there is a strong tendency to generate microcracks. In addition, the low thermal expansion ceramics of the present invention may contain a trace amount of impurities in addition to β-eucryptite and MgO.
【００１９】本発明の低熱膨張性セラミックスにおい
て、ボイド率（気孔率）が０．１体積％未満かつ平均ボ
イド径が２μｍ未満であるのが好ましく、ボイド率が
０．１体積％以上では、鏡面加工後の製品面の光反射率
が低くなる。平均ボイド径が２μｍ以上では、半導体製
造装置に用いたとき光によってＳｉウェハ等の位置決め
を行う際に、位置決め用として十分な光反射特性が得ら
れない。より好ましくは、最大ボイド径が３μｍ未満で
ある。In the low thermal expansion ceramics of the present invention, the void ratio (porosity) is preferably less than 0.1% by volume and the average void diameter is less than 2 μm. The light reflectance of the product surface after processing decreases. If the average void diameter is 2 μm or more, sufficient light reflection characteristics for positioning cannot be obtained when positioning a Si wafer or the like by light when used in a semiconductor manufacturing apparatus. More preferably, the maximum void diameter is less than 3 μm.
【００２０】本発明の軽量低熱膨張性セラミックスは以
下の工程〔１〕〜〔３〕のようにして製造する。The lightweight, low-thermal-expansion ceramic of the present invention is manufactured by the following steps [1] to [3].
【００２１】〔１〕重量％比でＬｉ2 Ｏ：Ａｌ2 Ｏ3 ：
ＳｉＯ2 ＝１２．５：４０．５：４７に調製した原料粉
末を用いる。各成分の増減により結晶中にムライト生成
やクリストバライト生成が見られるようになる。その場
合、熱膨張率が増加するため、重量％比のバラツキは１
重量％以内に抑えることが好ましい。そして、アルコキ
シド法で製造した上記組成比で平均粒径５〜７μｍのＬ
ＡＳ原料粉末９５〜９９重量％に対して、比表面積１２
〜１４ｍ2 ／ｇ、平均粒径０．５〜０．７μｍのＭｇＯ
粉末を１〜５重量％添加する。[1] Li 2 O: Al 2 O 3 :
The raw material powder prepared at SiO 2 = 12.5: 40.5: 47 is used. Due to the increase or decrease of each component, mullite generation and cristobalite generation can be seen in the crystal. In this case, since the coefficient of thermal expansion increases, the variation in the weight% ratio is 1
It is preferable to keep it within the range of weight%. Then, L having an average particle size of 5 to 7 μm at the above composition ratio manufactured by the alkoxide method.
The specific surface area is 12 based on 95 to 99% by weight of the AS raw material powder.
~14m 2 / g, MgO having an average particle diameter of 0.5~0.7μm
Add 1-5% by weight of powder.
【００２２】〔２〕ＬＡＳ原料粉末とＭｇＯ粉末を配合
の後、振動ミル等を使用して平均粒径１μｍ未満となる
ように粉砕混合し、所定形状に成形する。[2] After blending the LAS raw material powder and the MgO powder, they are pulverized and mixed using a vibration mill or the like so as to have an average particle size of less than 1 μm, and formed into a predetermined shape.
【００２３】〔３〕大気雰囲気下で１０００〜１２００
℃、好ましくは１０４０〜１１３０℃で焼結させること
で、比重２．２〜２．４、熱膨張率−０．４×１０-6〜
０．１×１０-6／℃、ヤング率１１０〜１２０ＧＰａと
なる軽量且つ高剛性の低熱膨張性セラミックスを製造で
きる。また、ＬＡＳ原料粉末及びＭｇＯ粉末からなる原
料粉末を所定形状に成形した後、大気雰囲気下で９００
〜１０００℃で相対密度９０％以上に焼結した後、１１
００〜１２００℃、１００気圧以上で加圧焼成すること
により、気孔率０．１％未満かつ平均ボイド径２μｍ未
満に緻密化することができる。加圧焼成時の温度が１１
００℃未満では磁器の緻密化が不十分であり、１２００
℃を超えると磁器の溶融がはじまり良好な磁器が得られ
なくなる。また、圧力１００気圧未満では、ボイド低減
効果が得られない。[3] 1000-1200 under air atmosphere
C., preferably by sintering at 1040 to 1130 ° C., to obtain a specific gravity of 2.2 to 2.4 and a coefficient of thermal expansion of −0.4 × 10 −6 to
A lightweight, high-rigidity, low-thermal-expansion ceramic having 0.1 × 10 −6 / ° C. and a Young's modulus of 110 to 120 GPa can be manufactured. After the raw material powder composed of the LAS raw material powder and the MgO powder has been formed into a predetermined shape,
After sintering at a relative density of 90% or more at ~ 1000 ° C, 11
By baking under pressure at 100 to 1200 ° C. and 100 atm or more, the porosity can be reduced to less than 0.1% and the average void diameter to less than 2 μm. Pressure firing temperature is 11
If the temperature is lower than 00 ° C., the densification of the porcelain is insufficient, and 1200
When the temperature exceeds ℃, melting of the porcelain starts, and good porcelain cannot be obtained. If the pressure is less than 100 atm, the effect of reducing voids cannot be obtained.
【００２４】このようにして得られた低熱膨張性セラミ
ックスは、窒化珪素セラミックスやコージェライトセラ
ミックス、ＫＺＰ（リン酸ジルコニウムカリウム）と比
較して、比重が２．２〜２．４と小さく、アルミナセラ
ミックス及び窒化珪素セラミックスと比較して、熱膨張
率が−０．４×１０-6〜０．１×１０-6／℃と熱膨張率
が実質的に０、又は０近傍の値を示す。また、コージェ
ライトセラミックス等の低熱膨張材料の中ではヤング率
が１１０〜１２０ＧＰａと高くなる。更に、半導体製造
用の露光装置等用として、表面平滑性や表面コーティン
グ性に優れる、ボイド率０．１体積％未満かつ平均ボイ
ド径２μｍ未満の軽量低熱膨張性及び高剛性特性を有す
る。The low thermal expansion ceramic thus obtained has a specific gravity of 2.2 to 2.4 smaller than that of silicon nitride ceramics, cordierite ceramics, or KZP (potassium zirconium phosphate). And a coefficient of thermal expansion of −0.4 × 10 −6 to 0.1 × 10 −6 / ° C. as compared with silicon nitride ceramics, and a coefficient of thermal expansion substantially equal to or near zero. Further, among low thermal expansion materials such as cordierite ceramics, the Young's modulus is as high as 110 to 120 GPa. Furthermore, it has a light weight, low thermal expansion property and a high rigidity characteristic of being excellent in surface smoothness and surface coating property and having a void ratio of less than 0.1% by volume and an average void diameter of less than 2 μm for use in an exposure apparatus for manufacturing a semiconductor.
【００２５】かくして、本発明は、半導体製造工程で使
用される露光装置等の各種装置、部品及び治具の材料と
して最適なものであって、軽量で低熱膨張率を有すると
共に高剛性のセラミックスを得ることができる。Thus, the present invention is suitable as a material for various apparatuses, parts, and jigs such as an exposure apparatus used in a semiconductor manufacturing process. Obtainable.
【００２６】尚、本発明は上記実施形態に限定されるも
のではなく、本発明の要旨を逸脱しない範囲内で種々の
変更を行っても何ら差し支えない。It should be noted that the present invention is not limited to the above embodiment, and various changes may be made without departing from the scope of the present invention.
【００２７】[0027]
【実施例】（実施例１）平均粒径５．５μｍのβ−ユー
クリプタイト粉末に対して、比表面積１２．６ｍ2 ／
ｇ、平均粒径０．６μｍのＭｇＯ粉末を、０重量％，１
重量％，２重量％，３重量％，４重量％，５重量％，６
重量％の割合で各々配合して原料粉末を調製し、これら
を振動ミルにより７２時間混合した後、造粒、乾燥後、
乾式プレス成形により試験片形状にした。原料粉末の平
均粒径及びＭｇＯ添加量が種々に異なる８種類の試験片
について、更に各々焼成温度を変えて大気雰囲気下で焼
成し、セラミックス磁器を製作し評価を行った。このう
ち、気孔率が０．１％未満となる緻密体が得られたＮ
ｏ．３，４，５の１０４０℃焼成品について、特性評価
を行った。評価結果は表２に示す。尚、表１においてｗ
ｔ％は重量％、ｖｏｌ％は体積％を意味し、原料粉末の
平均粒径はマイクロトラック法によって測定した。EXAMPLES Example 1 Specific surface area of 12.6 m 2 / β-eucryptite powder having an average particle size of 5.5 μm.
g, MgO powder having an average particle size of 0.6 μm was
Wt%, 2 wt%, 3 wt%, 4 wt%, 5 wt%, 6
The raw material powders were prepared by blending each in a ratio of weight%, and these were mixed by a vibration mill for 72 hours, and then granulated and dried.
The test piece was formed by dry press molding. Eight kinds of test pieces having various average particle diameters and different amounts of MgO added to the raw material powder were fired in the air atmosphere at different firing temperatures, and ceramic porcelain was manufactured and evaluated. Among them, a dense body having a porosity of less than 0.1% was obtained.
o. Characteristics of 3, 4, and 5 fired products at 1040 ° C. were evaluated. Table 2 shows the evaluation results. In Table 1, w
t% means% by weight, vol% means% by volume, and the average particle size of the raw material powder was measured by a microtrack method.
【００２８】[0028]
【表１】 [Table 1]
【００２９】[0029]
【表２】 [Table 2]
【００３０】表１に示すように、ＮＯ．１のＬＡＳ原料
粉末の平均粒径１．８μｍ、ＭｇＯ２ｗｔ％のもので
は、いずれの焼成温度においてもボイド率が２．１体積
％以上となり、緻密体は得られなかった。ＮＯ．２の平
均粒径０．７μｍ、ＭｇＯ０ｗｔ％のものでは、いずれ
の焼成温度においてもボイド率が２．６体積％以上とな
り、緻密体は得られなかった。ＮＯ．３の平均粒径０．
７μｍ、ＭｇＯ１ｗｔ％のものでは、焼成温度１０４０
℃，１１３０℃でボイド率が０．１体積％未満となり、
緻密体が得られた。ＮＯ．４の平均粒径０．７μｍ、Ｍ
ｇＯ２ｗｔ％のものでは、１０４０℃，１１３０℃でボ
イド率が０．１体積％未満となり、緻密体が得られた。As shown in Table 1, NO. With the LAS raw material powder of No. 1 having an average particle size of 1.8 μm and MgO of 2 wt%, the void ratio was 2.1% by volume or more at any firing temperature, and a dense body was not obtained. NO. In the case of No. 2 having an average particle diameter of 0.7 μm and MgO of 0 wt%, the void ratio was 2.6% by volume or more at any firing temperature, and a dense body was not obtained. NO. Average particle size of 0.3
In the case of 7 μm and 1 wt% of MgO, the firing temperature is 1040
At 1130 ° C, the void fraction becomes less than 0.1% by volume,
A dense body was obtained. NO. Average particle size of 0.7 μm, M
In the case of gO2 wt%, the void ratio was less than 0.1% by volume at 1040 ° C. and 1130 ° C., and a dense body was obtained.
【００３１】また、ＮＯ．５の平均粒径０．７μｍ、Ｍ
ｇＯ３ｗｔ％のものでは、１０４０℃，１１３０℃でボ
イド率が０．１体積％未満となり、緻密体が得られた。
ＮＯ．６の平均粒径０．７μｍ、ＭｇＯ４ｗｔ％のもの
では、１０４０℃でボイド率が０．１体積％未満とな
り、緻密体が得られた。ＮＯ．７の平均粒径０．７μ
ｍ、ＭｇＯ５ｗｔ％のものでは、１０４０℃でボイド率
が０．１体積％未満となり、緻密体が得られた。ＮＯ．
８の平均粒径０．７μｍ、ＭｇＯ６ｗｔ％のものでは、
いずれの焼成温度においてもボイド率が０．８体積％以
上となり緻密体は得られなかった。In the case of NO. 5, average particle size 0.7 μm, M
With gO3 wt%, the void fraction was less than 0.1% by volume at 1040 ° C and 1130 ° C, and a dense body was obtained.
NO. In the case of No. 6 having an average particle diameter of 0.7 μm and MgO of 4 wt%, the void ratio was less than 0.1% by volume at 1040 ° C., and a dense body was obtained. NO. 0.7 average particle size of 7
With m and MgO of 5 wt%, the void ratio was less than 0.1% by volume at 1040 ° C., and a dense body was obtained. NO.
8 having an average particle diameter of 0.7 μm and MgO of 6 wt%:
At any of the firing temperatures, the void ratio was 0.8% by volume or more, and no dense body was obtained.
【００３２】表２に示すように、本発明に基づき、β−
ユークリプタイト粉末に、比表面積１２．６ｍ2 ／ｇ、
平均粒径０．６μｍのＭｇＯ粉末を１〜３重量％加え、
平均粒径０．７μｍに粉砕した原料粉末を使用して、大
気雰囲気下で１０４０℃で焼成することにより、比重
２．３、熱膨張率−０．４×１０-6〜０．１×１０-6／
℃、ヤング率１１０〜１２０ＧＰａ、気孔率０．１体積
％未満の緻密なセラミックスを得ることができた。ま
た、原料粉末を中空体とすることで更に軽量化すること
も可能である。As shown in Table 2, based on the present invention, β-
Specific surface area of 12.6 m 2 / g to eucryptite powder,
1 to 3% by weight of MgO powder having an average particle size of 0.6 μm is added,
The raw material powder pulverized to an average particle diameter of 0.7 μm is calcined at 1040 ° C. in the air atmosphere to obtain a specific gravity of 2.3 and a coefficient of thermal expansion of −0.4 × 10 −6 to 0.1 × 10. -6 /
C., a dense ceramic having a Young's modulus of 110 to 120 GPa and a porosity of less than 0.1% by volume could be obtained. Further, it is possible to further reduce the weight by making the raw material powder a hollow body.
【００３３】（実施例２）平均粒径５．５μｍのβ−ユ
ークリプタイト粉末に対して、比表面積１２．６ｍ2 ／
ｇ、平均粒径０．６μｍのＭｇＯ粉末を、２重量％，５
重量％の割合で各々配合して原料粉末を調製し、これら
を振動ミルにより７２時間混合した後、造粒、乾燥後、
乾式プレス成形により試験片形状にした。その後、焼成
温度１０００℃で焼成した後、ＨＰ（加圧焼成）処理を
行った。ＨＰ条件は、加圧力を１００気圧，３００気圧
の２種とし、それぞれに対し１０００℃，１１００℃，
１２００℃，１３００℃で焼成し、合計８種類のＨＰ処
理を行った。これらにつき平均ボイド率（気孔率）、平
均ボイド径の評価を行い、その結果を表３に示す。尚、
平均ボイド率及び平均ボイド径の測定は、試験片表面又
は断面の光学顕微鏡による倍率１００倍又は１０００倍
の写真を１０視野とり、ボイドを球状であると仮定し画
像処理してボイドの占有面積から平均ボイド率を近似的
に導出し、また平均ボイド径は各ボイド径を観測し平均
値をとることで行った。Example 2 Specific surface area of 12.6 m 2 / β-eucryptite powder having an average particle size of 5.5 μm
g, MgO powder having an average particle size of 0.6 μm was
The raw material powders were prepared by blending each in a ratio of weight%, and these were mixed by a vibration mill for 72 hours, and then granulated and dried.
The test piece was formed by dry press molding. Then, after baking at a baking temperature of 1000 ° C., an HP (pressure baking) treatment was performed. The HP conditions were two kinds of pressures of 100 atm and 300 atm, 1000 ° C, 1100 ° C,
Baking was performed at 1200 ° C. and 1300 ° C., and a total of eight types of HP treatments were performed. The average void ratio (porosity) and average void diameter were evaluated for these, and the results are shown in Table 3. still,
The measurement of the average void fraction and the average void diameter is performed by taking 10 fields of view of the test specimen surface or cross section at a magnification of 100 or 1000 by an optical microscope, assuming that the void is spherical, and performing image processing to determine the void occupied area. The average void fraction was approximately derived, and the average void diameter was obtained by observing each void diameter and taking an average value.
【００３４】[0034]
【表３】 [Table 3]
【００３５】加圧力が１００気圧では処理温度１１００
〜１２００℃で、平均ボイド率が０．１体積％未満、平
均ボイド径が１．２〜１．８μｍとなった。１３００℃
でβ−ユークリプタイトは溶融した。３００気圧では処
理温度１１００〜１２００℃で、平均ボイド率が０．１
体積％未満、平均ボイド径が１．０〜１．９μｍとなっ
た。１３００℃でβ−ユークリプタイトは溶融した。従
って、１１００℃〜１２００℃の範囲で平均ボイド率
０．１体積％未満、平均ボイド径２μｍ未満のセラミッ
クス磁器が得られることが判明した。When the pressure is 100 atm, the processing temperature is 1100
At 1200 ° C., the average void ratio was less than 0.1% by volume, and the average void diameter was 1.2 to 1.8 μm. 1300 ° C
As a result, β-eucryptite melted. At 300 atm, the processing temperature is 1100 to 1200 ° C and the average void fraction is 0.1
%, And the average void diameter was 1.0 to 1.9 μm. At 1300 ° C., β-eucryptite melted. Therefore, it was found that ceramic porcelain having an average void fraction of less than 0.1% by volume and an average void diameter of less than 2 μm was obtained in the range of 1100 ° C. to 1200 ° C.
【００３６】[0036]
【発明の効果】本発明は、化学式ＬｉＡｌＳｉＯ4 で表
されるβ−ユークリプタイトを９５〜９９重量％、マグ
ネシアを１〜５重量％を含むことにより、熱膨張率−
０．４×１０-6〜０．１×１０-6／℃、ヤング率１１０
〜１２０ＧＰａ、比重が２．２〜２．４と軽量で低熱膨
張率を有すると共に高剛性のセラミックスが得られる。
そして、本発明の低熱膨張性セラミックスは、超微細な
電子回路を形成するために半導体ウェハに露光処理等を
行う半導体製造用の各種装置及び部品、例えばＸ−Ｙス
テージ及びその部品、真空チャック、静電チャック、ミ
ラー等に用いることにより、温度変化に対する寸法安定
性に優れ、変形や振動の影響が実質的に解消される。According to the present invention, a thermal expansion coefficient is obtained by containing 95 to 99% by weight of β-eucryptite represented by the chemical formula LiAlSiO 4 and 1 to 5% by weight of magnesia.
0.4 × 10 -6 to 0.1 × 10 -6 / ° C, Young's modulus 110
A lightweight, low coefficient of thermal expansion coefficient of up to 120 GPa and a specific gravity of 2.2 to 2.4, and a highly rigid ceramic can be obtained.
And the low thermal expansion ceramics of the present invention, various devices and parts for semiconductor manufacturing, such as an XY stage and parts thereof, for performing exposure processing and the like on a semiconductor wafer to form an ultra-fine electronic circuit, a vacuum chuck, By using it for an electrostatic chuck, a mirror, or the like, it has excellent dimensional stability against temperature changes, and the effects of deformation and vibration are substantially eliminated.
【００３７】また、本発明は、９５〜９９重量％のβ−
ユークリプタイト原料粉末と１〜５重量％のマグネシア
原料粉末とを含むセラミックス原料を酸化雰囲気下で焼
結し、その後１１００〜１２００℃及び１００気圧以上
で加圧加焼処理することにより、ボイド率０．１体積％
未満かつ平均ボイド径２μｍ未満の低熱膨張性セラミッ
クスが得られる。また、前記構成により、前記各種装置
及び部品表面の平滑性を向上させることができ、その結
果優れた構造的精度及び位置精度が得られ、ＬＳＩ等の
半導体電子回路部品の品質と量産性を高めることができ
る。Further, the present invention relates to a method for preparing 95-99% by weight of β-
A ceramic raw material containing eucryptite raw material powder and 1 to 5% by weight magnesia raw material powder is sintered in an oxidizing atmosphere, and then subjected to pressure sintering at 1100 to 1200 ° C. and 100 atm or more to obtain a void fraction. 0.1% by volume
And a low thermal expansion ceramic having an average void diameter of less than 2 μm is obtained. Further, with the above-described configuration, the smoothness of the surfaces of the various devices and components can be improved. As a result, excellent structural accuracy and positional accuracy can be obtained, and the quality and mass productivity of semiconductor electronic circuit components such as LSIs can be improved. be able to.
Claims (3)
ークリプタイトを９５〜９９重量％、マグネシアを１〜
５重量％を含むことを特徴とする低熱膨張性セラミック
ス。(1) 95-99% by weight of β-eucryptite represented by the general formula LiAlSiO 4 and magnesia of 1-99% by weight;
Low thermal expansion ceramics containing 5% by weight.
ド径が２μｍ未満である請求項１記載の低熱膨張性セラ
ミックス。2. The low thermal expansion ceramic according to claim 1, wherein the void fraction is less than 0.1% by volume and the average void diameter is less than 2 μm.
原料粉末と１〜５重量％のマグネシア原料粉末とを含む
セラミックス原料を酸化雰囲気下で焼結し、その後１１
００〜１２００℃及び１００気圧以上で加圧加焼処理す
ることを特徴とする低熱膨張性セラミックスの製造方
法。3. A ceramic raw material containing 95 to 99% by weight of β-eucryptite raw material powder and 1 to 5% by weight of magnesia raw material powder is sintered in an oxidizing atmosphere.
A method for producing a low-thermal-expansion ceramic, comprising subjecting to pressure baking at 100 to 1200 ° C. and at least 100 atm.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP02211199A JP3805119B2 (en) | 1999-01-29 | 1999-01-29 | Method for producing low thermal expansion ceramics |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP02211199A JP3805119B2 (en) | 1999-01-29 | 1999-01-29 | Method for producing low thermal expansion ceramics |
Related Child Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2006102218A Division JP4429288B2 (en) | 2006-04-03 | 2006-04-03 | Low thermal expansion ceramics and members for semiconductor manufacturing equipment using the same |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2000219572A true JP2000219572A (en) | 2000-08-08 |
| JP3805119B2 JP3805119B2 (en) | 2006-08-02 |
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| Application Number | Title | Priority Date | Filing Date |
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| JP02211199A Expired - Fee Related JP3805119B2 (en) | 1999-01-29 | 1999-01-29 | Method for producing low thermal expansion ceramics |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2002024600A1 (en) * | 2000-09-20 | 2002-03-28 | Sumitomo Metal Industries, Ltd. | Low thermal expansion ceramic and member for exposure system |
| JP2002173363A (en) * | 2000-12-06 | 2002-06-21 | Kyocera Corp | Lithium alumino-silicate-base ceramic |
| JP2002173364A (en) * | 2000-12-06 | 2002-06-21 | Kyocera Corp | Lithium alumino-silicate-base ceramic |
| JP2007261842A (en) * | 2006-03-28 | 2007-10-11 | Shiga Pref Gov | Ni CERAMIC COMPOSITE AND METHOD OF MANUFACTURING THE SAME |
| CN108302942A (en) * | 2018-01-08 | 2018-07-20 | 朱性宇 | Electrode material of lithium battery prepares the preparation method with saggar, the protective layer of the saggar and saggar |
| CN114887613A (en) * | 2022-06-21 | 2022-08-12 | 重庆大学 | Magnesium-based photo-thermal catalytic material for carbon dioxide hydrogenation reduction reaction, preparation method and application |
-
1999
- 1999-01-29 JP JP02211199A patent/JP3805119B2/en not_active Expired - Fee Related
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2002024600A1 (en) * | 2000-09-20 | 2002-03-28 | Sumitomo Metal Industries, Ltd. | Low thermal expansion ceramic and member for exposure system |
| US7112549B2 (en) * | 2000-09-20 | 2006-09-26 | Sumitomo Metal Industries, Ltd. | Low thermal expansion ceramic and member for exposure system |
| JP2002173363A (en) * | 2000-12-06 | 2002-06-21 | Kyocera Corp | Lithium alumino-silicate-base ceramic |
| JP2002173364A (en) * | 2000-12-06 | 2002-06-21 | Kyocera Corp | Lithium alumino-silicate-base ceramic |
| JP4658311B2 (en) * | 2000-12-06 | 2011-03-23 | 京セラ株式会社 | Lithium aluminosilicate ceramics |
| JP4658312B2 (en) * | 2000-12-06 | 2011-03-23 | 京セラ株式会社 | Lithium aluminosilicate ceramics |
| JP2007261842A (en) * | 2006-03-28 | 2007-10-11 | Shiga Pref Gov | Ni CERAMIC COMPOSITE AND METHOD OF MANUFACTURING THE SAME |
| CN108302942A (en) * | 2018-01-08 | 2018-07-20 | 朱性宇 | Electrode material of lithium battery prepares the preparation method with saggar, the protective layer of the saggar and saggar |
| CN114887613A (en) * | 2022-06-21 | 2022-08-12 | 重庆大学 | Magnesium-based photo-thermal catalytic material for carbon dioxide hydrogenation reduction reaction, preparation method and application |
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| Publication number | Publication date |
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| JP3805119B2 (en) | 2006-08-02 |
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