JP2555938Y2 - Vacuum chuck - Google Patents
Vacuum chuckInfo
- Publication number
- JP2555938Y2 JP2555938Y2 JP6041191U JP6041191U JP2555938Y2 JP 2555938 Y2 JP2555938 Y2 JP 2555938Y2 JP 6041191 U JP6041191 U JP 6041191U JP 6041191 U JP6041191 U JP 6041191U JP 2555938 Y2 JP2555938 Y2 JP 2555938Y2
- Authority
- JP
- Japan
- Prior art keywords
- porous ceramic
- ceramic plate
- glass
- vacuum chuck
- outer peripheral
- 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.)
- Expired - Lifetime
Links
Description
【０００１】[0001]
【産業上の利用分野】本考案は、真空チャックに関する
ものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vacuum chuck.
【０００２】[0002]
【従来の技術】例えば半導体製造工程において、パター
ン成形後のウェハの厚み研磨工程、パックグライディン
グ、ウェハへの保護テープの貼付け等の工程でウェハを
固定支持するために真空チャックが使用されている。こ
の種の真空チャックとしては、例えば図４に示すよう
に、吸着面を構成する多孔質セラミック板101と、これ
の外周に接合された緻密質セラミックスからなる外周シ
ール層102と、これら多孔質セラミック板101及び外周シ
ール層102を支持する取付台103とを備えるものがある。
そして、上記多孔質セラミック板101と外周シール層102
との接合にはエポキシ系の接着剤が使用されている。2. Description of the Related Art In a semiconductor manufacturing process, for example, a vacuum chuck is used for fixing and supporting a wafer in a process of polishing a thickness of a wafer after pattern formation, pack gliding, attaching a protective tape to the wafer, and the like. As this type of vacuum chuck, for example, as shown in FIG. 4, a porous ceramic plate 101 constituting an adsorption surface, an outer peripheral sealing layer 102 made of dense ceramics joined to the outer periphery thereof, Some include a plate 101 and a mount 103 for supporting the outer peripheral seal layer 102.
Then, the porous ceramic plate 101 and the outer peripheral seal layer 102
An epoxy-based adhesive is used for bonding with the substrate.
【０００３】[0003]
【考案が解決しようとする課題】ところで、このような
真空チャックで半導体ウェハを吸着支持して研磨する場
合、多孔質セラミック板101の平面出しをするため、研
磨材(ダイヤモンド砥粒）の目立てあるいは目直しを兼
ねて予め研磨材で多孔質セラミック板101を僅かに研削
している。When a semiconductor wafer is suction-supported and polished by such a vacuum chuck, the polishing material (diamond abrasive grains) needs to be sharpened or flattened in order to make the porous ceramic plate 101 flat. The porous ceramic plate 101 is slightly ground in advance with an abrasive for the purpose of dressing.
【０００４】この研削においては多孔質セラミック板10
1と材質が異なる外周シール層102とでは研磨量が異なる
ため、例えば図５に示すように、数10μｍないし数百μ
ｍ程度多孔質セラミック板101が低くなる段差が生じる
ことがある。このような段差が生じると、この段差から
リークが生じて吸着力が低下し、半導体ウェハの固定が
不確実になって加工中に破損することがあった。In this grinding, a porous ceramic plate 10 is used.
Since the polishing amount is different between 1 and the outer peripheral sealing layer 102 made of a different material, for example, as shown in FIG.
There may be a step where the porous ceramic plate 101 is lowered by about m. When such a step occurs, a leak is generated from the step, and the attraction force is reduced, so that the fixing of the semiconductor wafer becomes uncertain and the semiconductor wafer may be damaged during processing.
【０００５】本考案は、上記の事情に鑑み、研磨によっ
て多孔質セラミック板と外周シール層との間に発生する
段差を無視できる程度に小さくできるようにした真空チ
ャックを提供することを目的とする。The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a vacuum chuck in which a step generated between a porous ceramic plate and an outer peripheral sealing layer by polishing can be reduced to a negligible level. .
【０００６】[0006]
【課題を解決するための手段】本考案に係る真空チャッ
クは、例えば図１に示すように、吸着面を構成する多孔
質セラミック板１と、これの外周にガラス接合された緻
密質セラミックスからなる外周シール層２とを備える真
空チャックにおいて、上記の目的を達成するため、多孔
質セラミック板１の周囲部１ａに低融点ガラス４を含浸
させて、空気流通を阻止するガラス層を形成する。The vacuum chuck according to the present invention comprises, as shown in FIG. 1, for example, a porous ceramic plate 1 constituting an adsorbing surface and a dense ceramic glass bonded to the outer periphery of the porous ceramic plate. In the vacuum chuck provided with the outer peripheral sealing layer 2, in order to achieve the above object, a low melting point glass 4 is impregnated in a peripheral portion 1a of the porous ceramic plate 1 to form a glass layer that blocks air flow.
【０００７】[0007]
【作用】本考案においては、多孔質セラミック板１の周
囲部１ａに低融点ガラス４を含浸させることにより、多
孔質セラミック基板１の周囲部１ａが目止めされて緻密
質化され、多孔質セラミック板１の周囲に接合される外
周シール層２と機械的特性が近似するようになって、研
削時の段差を極めて小さくできる。In the present invention, the peripheral portion 1a of the porous ceramic plate 1 is impregnated with the low melting point glass 4 so that the peripheral portion 1a of the porous ceramic substrate 1 is sealed and densified. Since the mechanical properties are similar to those of the outer peripheral seal layer 2 bonded around the plate 1, the step during grinding can be made extremely small.
【０００８】[0008]
【実施例】以下、本考案の実施例を図面に基づき具体的
に説明する。図１に示すように、本考案の一実施例に係
る真空チャックは、吸着面を構成する多孔質セラミック
板１と、これの外周にガラス接合された緻密質セラミッ
クスからなる外周シール層２と、これら多孔質セラミッ
ク板１及び外周シール層２を保持する取付台３とを備え
る。また、上記多孔質セラミック板１は気孔率30〜40
％、平均細孔径５〜500μｍとしてある。DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be specifically described below with reference to the drawings. As shown in FIG. 1, the vacuum chuck according to one embodiment of the present invention includes a porous ceramic plate 1 constituting an adsorption surface, an outer peripheral sealing layer 2 made of dense ceramics bonded to the outer periphery of the porous ceramic plate 1, A mounting base 3 for holding the porous ceramic plate 1 and the outer peripheral sealing layer 2 is provided. The porous ceramic plate 1 has a porosity of 30 to 40.
%, And the average pore diameter is 5 to 500 μm.
【０００９】図２に示すように、上記多孔質セラミック
板１の周囲部１ａには低融点ガラス４を含浸させてあ
り、多孔質セラミック板１と外周シール層２とは低融点
ガラス５でガラス付けしてある。多孔質セラミック板１
の周囲部１ａに低融点ガラス４を含浸させる方法は、特
に限定されず、例えば多孔質セラミック板１の原料粉末
を型込めする時に周囲から約８〜10mmの周囲部１ａにガ
ラス粉末を混入させ、この後焼成する方法を採用するこ
とができる。あるいは焼成後の多孔質セラミック板１の
周囲部にガラスペーストを含浸させてもよい。As shown in FIG. 2, the peripheral portion 1a of the porous ceramic plate 1 is impregnated with a low melting point glass 4, and the porous ceramic plate 1 and the outer peripheral sealing layer 2 are made of a low melting point glass 5 made of glass. I have attached. Porous ceramic plate 1
The method for impregnating the low melting point glass 4 into the peripheral portion 1a is not particularly limited. For example, when the raw material powder of the porous ceramic plate 1 is molded, the glass powder is mixed into the peripheral portion 1a approximately 8 to 10 mm from the periphery. Thereafter, a method of firing may be employed. Alternatively, the periphery of the fired porous ceramic plate 1 may be impregnated with a glass paste.
【００１０】なお、多孔質セラミック板１の原料粉末と
しては、例えば、アルミナ、ジルコニア、窒化珪素等、
一般に多孔質セラミック板１を形成できるセラミック粉
末を使用すればよく、ここでは、比較的安価にかつ容易
に入手できるアルミナを主成分とするセラミック粉末を
原料粉末として使用した。多孔質セラミック板１に含浸
される低融点ガラス４は、特に限定されないが、熱膨張
係数が比較的原料粉末のそれに近似していることが好ま
しく、例えば平均熱膨張率が１〜100×10-7(/℃)程度の
ものであることが好ましい。The raw material powder for the porous ceramic plate 1 includes, for example, alumina, zirconia, silicon nitride and the like.
Generally, a ceramic powder capable of forming the porous ceramic plate 1 may be used. Here, a ceramic powder containing alumina as a main component, which is relatively inexpensive and easily available, is used as a raw material powder. The low-melting glass 4 impregnated in the porous ceramic plate 1 is not particularly limited, but preferably has a coefficient of thermal expansion relatively similar to that of the raw material powder, for example, an average coefficient of thermal expansion of 1 to 100 × 10 −. It is preferably about 7 (/ ° C.).
【００１１】また、低融点ガラス４の軟化温度は原料粉
末の軟化温度よりも低ければよく、軟化点が例えば900
〜920℃程度のものを使用すればよい。多孔質セラミッ
ク板１と外周シール層２とは、加工技術の発達した今日
では特に限定されないが、なるべく材質や特性、特に、
熱膨張係数が近似するものを用いることが好ましい。The softening temperature of the low-melting glass 4 may be lower than the softening temperature of the raw material powder.
A temperature of about 920 ° C. may be used. The porous ceramic plate 1 and the outer peripheral seal layer 2 are not particularly limited in the present day when the processing technology has been developed.
It is preferable to use one having a similar thermal expansion coefficient.
【００１２】多孔質セラミック板１と外周シール層２と
をガラス接合する方法は特に限定されず、例えば予め低
融点ガラス４を含浸させた多孔質セラミック板１の周面
にペースト状の低融点ガラス５を例えば約0.2mm程度の
厚さに塗布し、多孔質セラミック板１を外周シール層２
に嵌め込んだ後、低融点ガラス５の軟化点よりも高温に
加熱させる方法を採用することができる。The method of glass-bonding the porous ceramic plate 1 and the outer peripheral sealing layer 2 is not particularly limited. For example, a paste-like low-melting glass is formed on the peripheral surface of the porous ceramic plate 1 impregnated with the low-melting glass 4 in advance. 5 is applied to a thickness of, for example, about 0.2 mm.
Then, a method of heating the glass to a temperature higher than the softening point of the low-melting glass 5 can be adopted.
【００１３】この方法を採用する場合、多孔質セラミッ
ク板１の周面に塗布される低融点ガラス５の軟化点は多
孔質セラミック板１の物性が変化する温度よりも低けれ
ばよく、例えば900〜920℃程度の低融点ガラス４を使用
すればよい。また、多孔質セラミック板１の周面に塗布
される低融点ガラス５は多孔質セラミック板１への付着
性を得るため、例えば1500〜2000ps程度の粘度を備える
必要がある。When this method is adopted, the softening point of the low-melting glass 5 applied to the peripheral surface of the porous ceramic plate 1 may be lower than the temperature at which the physical properties of the porous ceramic plate 1 change. What is necessary is just to use the low melting point glass 4 of about 920 degreeC. Further, the low-melting glass 5 applied to the peripheral surface of the porous ceramic plate 1 needs to have a viscosity of, for example, about 1500 to 2000 ps in order to obtain adhesion to the porous ceramic plate 1.
【００１４】更に、多孔質セラミック板１の周面に塗布
される低融点ガラス５は、後述するガラス接合後の冷却
時に低融点ガラス５と多孔質セラミック板１との間にク
ラックが発生することを防止するため、熱膨張係数が多
孔質セラミック板１の熱膨張係数に近似する例えば１〜
100×10-7(/℃)程度の低融点ガラスを使用することが好
ましい。Further, the low-melting glass 5 applied to the peripheral surface of the porous ceramic plate 1 may cause cracks to occur between the low-melting glass 5 and the porous ceramic plate 1 during cooling after glass bonding, which will be described later. In order to prevent this, the coefficient of thermal expansion approximates the coefficient of thermal expansion of the porous ceramic
It is preferable to use a glass having a low melting point of about 100 × 10 −7 (/ ° C.).
【００１５】また、これらの低融点ガラスとしては、例
えばホウケイ酸ガラス、ケイ酸系ガラスを用いる。この
実施例では、平均熱膨張係数が64.2×10-7/℃、軟化点
が914℃、粘度が1800psの低融点ガラス５を予め低融点
ガラス４を含浸させた多孔質セラミック板１の下面及び
周面に塗布し、920 ℃程度に加熱して多孔質セラミック
板１と外周シール層２とをガラス接合した。As these low melting point glasses, for example, borosilicate glass or silicate glass is used. In this embodiment, the lower surface of the porous ceramic plate 1 in which the low-melting glass 5 having an average coefficient of thermal expansion of 64.2 × 10 −7 / ° C., a softening point of 914 ° C., and a viscosity of 1800 ps was previously impregnated with the low-melting glass 4 was used. It was applied to the peripheral surface and heated to about 920 ° C. to bond the porous ceramic plate 1 and the outer peripheral sealing layer 2 with glass.
【００１６】このガラス接合の後、取付台３に多孔質セ
ラミック板１と外周シール層２とを搭載し、研磨したと
ころ、多孔質セラミック板１と外周シール層２との段差
は３〜４μｍ程度となり、更に、精度が高いラップ盤を
用いて研磨したところ、例えば図３に示すように、多孔
質セラミック板１と外周シール層２との段差が１μｍ以
下となった。After the glass bonding, the porous ceramic plate 1 and the outer peripheral sealing layer 2 are mounted on the mounting base 3 and polished. As a result, the step between the porous ceramic plate 1 and the outer peripheral sealing layer 2 is about 3 to 4 μm. Further, when polishing was performed using a high-precision lapping machine, for example, as shown in FIG. 3, the step between the porous ceramic plate 1 and the outer peripheral sealing layer 2 became 1 μm or less.
【００１７】また、多孔質セラミック板１の周囲部に低
融点ガラス４を含浸させて目止めしているので、多孔質
セラミック板１の周面から外気がリークし難くなり、こ
のリークによる真空吸着力の低下を防止して、確実に半
導体ウェハ等の加工物を真空吸着でき、高精度加工を行
うことができる。Further, since the peripheral portion of the porous ceramic plate 1 is impregnated with the low-melting glass 4 for sealing, the outside air hardly leaks from the peripheral surface of the porous ceramic plate 1, and the vacuum adsorption by the leak is performed. By preventing a reduction in force, a workpiece such as a semiconductor wafer can be reliably sucked in vacuum, and high-precision processing can be performed.
【００１８】[0018]
【考案の効果】以上のように、本考案によれば、多孔質
セラミック板の周囲部に低融点ガラスを含浸させること
により、多孔質セラミック基板の周囲部が目止めされて
緻密質化され、多孔質セラミック板の周囲に接合される
外周シール層と機械的特性が近似するようになる。As described above, according to the present invention, the periphery of the porous ceramic plate is impregnated with the low-melting glass, whereby the periphery of the porous ceramic substrate is sealed and densified. The mechanical properties are similar to those of the outer peripheral seal layer bonded around the porous ceramic plate.
【００１９】従って、研磨によって平面出しをする場合
に多孔質セラミック板と外周シール層との間に生じる段
差が小さくなり、段差からリークが生じ難くなるととも
に、多孔質セラミック基板の周囲部が目止めされ、多孔
質セラミック基板の周面から外気がリークすることが防
止され、リークによる真空吸着力の低下を防止して確実
に加工物を真空吸着することができる。その結果、例え
ば半導体ウェハの研磨における仕上げ平面度を高めるこ
とができ、高精度加工ができるようになる。Therefore, when a flat surface is formed by polishing, a step formed between the porous ceramic plate and the outer peripheral sealing layer is reduced, so that a leak hardly occurs from the step and a peripheral portion of the porous ceramic substrate is clogged. Thus, the outside air is prevented from leaking from the peripheral surface of the porous ceramic substrate, and the vacuum suction force is prevented from being reduced due to the leak, so that the workpiece can be reliably sucked in vacuum. As a result, for example, the finished flatness in polishing a semiconductor wafer can be increased, and high-precision processing can be performed.
【００２０】また、多孔質セラミック板と外周シール層
との間に生じる段差が例えば３〜４μｍ程度に小さくな
るので、ラップ盤による精密な面出し加工をすることが
でき、ラップ盤によって上記段差が例えば１μｍ以下に
なるように加工できる。更に、多孔質セラミック板の周
囲部が目止めされているので、多孔質セラミック板より
も小径の加工物を真空吸着する際に、多孔質セラミック
板の周囲部の上面が周囲に開放されていてもリークが生
ぜず、確実に加工物を多孔質セラミック板に吸着固定で
きる。Further, since a step generated between the porous ceramic plate and the outer peripheral sealing layer is reduced to, for example, about 3 to 4 μm, it is possible to carry out a precise surfacing process using a lapping machine. For example, it can be processed to have a thickness of 1 μm or less. Further, since the peripheral portion of the porous ceramic plate is sealed, the upper surface of the peripheral portion of the porous ceramic plate is open to the periphery when a workpiece having a smaller diameter than the porous ceramic plate is vacuum-adsorbed. No leakage occurs, and the workpiece can be securely fixed to the porous ceramic plate by suction.
【図１】本考案の一実施例に係る真空チャックの縦断面
図である。FIG. 1 is a longitudinal sectional view of a vacuum chuck according to an embodiment of the present invention.
【図２】本考案の一実施例に係る真空チャックの組立手
順を示すフロー図である。FIG. 2 is a flowchart showing a procedure for assembling the vacuum chuck according to the embodiment of the present invention;
【図３】本考案の一実施例に係る真空チャックの要部の
拡大縦断面図である。FIG. 3 is an enlarged vertical sectional view of a main part of the vacuum chuck according to the embodiment of the present invention;
【図４】従来例の縦断面図である。FIG. 4 is a longitudinal sectional view of a conventional example.
【図５】本考案が解決しようとする課題の説明図であ
る。FIG. 5 is an explanatory diagram of a problem to be solved by the present invention.
１…多孔質セラミック板 １ａ…周囲部 ２…外周シール層 ４…低融点ガラス DESCRIPTION OF SYMBOLS 1 ... Porous ceramic plate 1a ... Peripheral part 2 ... Peripheral seal layer 4 ... Low melting glass
Claims (1)
と、これの外周にガラス接合された緻密質セラミックス
からなる外周シール層とを備える真空チャックにおい
て、前記多孔質セラミック板の周囲部に空気流通を阻止
するためのガラス層を形成したことを特徴とする真空チ
ャック。1. A vacuum chuck comprising a porous ceramic plate constituting an adsorbing surface and an outer peripheral seal layer made of dense ceramics joined to the outer periphery of the porous ceramic plate by an air flow around the porous ceramic plate. A vacuum chuck formed with a glass layer for preventing the occurrence of a vacuum.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP6041191U JP2555938Y2 (en) | 1991-07-31 | 1991-07-31 | Vacuum chuck |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP6041191U JP2555938Y2 (en) | 1991-07-31 | 1991-07-31 | Vacuum chuck |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0513051U JPH0513051U (en) | 1993-02-19 |
| JP2555938Y2 true JP2555938Y2 (en) | 1997-11-26 |
Family
ID=13141413
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP6041191U Expired - Lifetime JP2555938Y2 (en) | 1991-07-31 | 1991-07-31 | Vacuum chuck |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2555938Y2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007253284A (en) * | 2006-03-23 | 2007-10-04 | Kyocera Corp | Vacuum chuck and vacuum suction device using it |
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| JP4549654B2 (en) * | 2003-11-04 | 2010-09-22 | 株式会社ディスコ | Cutting blade setup method |
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| KR100753302B1 (en) * | 2004-03-25 | 2007-08-29 | 이비덴 가부시키가이샤 | Vacuum chuck, suction board, polishing device, and method for manufacturing of semiconductor wafer |
| JP4704971B2 (en) * | 2006-07-21 | 2011-06-22 | 太平洋セメント株式会社 | Vacuum adsorption device |
| JP5288785B2 (en) * | 2007-12-13 | 2013-09-11 | 株式会社ディスコ | Wafer processing equipment |
| JP6294324B2 (en) * | 2012-08-31 | 2018-03-14 | セミコンダクター テクノロジーズ アンド インストゥルメンツ ピーティーイー リミテッド | Single ultra-flat wafer table structure for both wafer and film frame |
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-
1991
- 1991-07-31 JP JP6041191U patent/JP2555938Y2/en not_active Expired - Lifetime
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007253284A (en) * | 2006-03-23 | 2007-10-04 | Kyocera Corp | Vacuum chuck and vacuum suction device using it |
| JP4731368B2 (en) * | 2006-03-23 | 2011-07-20 | 京セラ株式会社 | Vacuum chuck and vacuum suction device using the same |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0513051U (en) | 1993-02-19 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EXPY | Cancellation because of completion of term |