JP2589064Y2 - Surface plate for polishing machine - Google Patents
Surface plate for polishing machineInfo
- Publication number
- JP2589064Y2 JP2589064Y2 JP1991100376U JP10037691U JP2589064Y2 JP 2589064 Y2 JP2589064 Y2 JP 2589064Y2 JP 1991100376 U JP1991100376 U JP 1991100376U JP 10037691 U JP10037691 U JP 10037691U JP 2589064 Y2 JP2589064 Y2 JP 2589064Y2
- Authority
- JP
- Japan
- Prior art keywords
- polishing machine
- surface plate
- polishing
- base metal
- ceramic
- 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 - Fee Related
Links
Description
【０００１】[0001]
【産業上の利用分野】この考案は、研磨機用定盤、特
に、母材金属の表面にセラミックス層を備えた研磨機用
定盤に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a platen for a polisher, and more particularly to a platen for a polisher provided with a ceramic layer on the surface of a base metal.
【０００２】[0002]
【従来の技術】ＩＣ基盤等の研磨機用定盤には、図４並
びに図５に示すような片面研磨機並びに両面研磨機が用
いられる。図４において、１１は定盤、１２は加圧ヘッ
ド、１３はワ−ク、１４は片面研磨機である。また図５
において、２１は上定盤、２２は下定盤、２３は太陽ギ
ヤ、２４はインタ−ナルギヤ、２５はドライバ−、２６
はサブシリンダ−、２７はメインシリンダ−、２８は両
面研磨機である。2. Description of the Related Art As a surface plate for a polishing machine such as an IC substrate, a single-side polishing machine and a double-side polishing machine as shown in FIGS. 4 and 5 are used. In FIG. 4, 11 is a surface plate, 12 is a pressure head, 13 is a work, and 14 is a one-side polishing machine. FIG.
, 21 is an upper surface plate, 22 is a lower surface plate, 23 is a sun gear, 24 is an internal gear, 25 is a driver, 26
Is a sub cylinder, 27 is a main cylinder, and 28 is a double-side polishing machine.
【０００３】これら片面研磨機１４の定盤１１並びに両
面研磨機２８の上定盤２１並びに下定盤２２の母材金属
は、従来から、鋳鉄、ステンレス、銅合金といった金属
材料が用いられている。例えば、図４の片面研磨機１４
又は図５の両面研磨機２８を用いて、半導体ウエハ−の
鏡面仕上げを行う場合、片面研磨機１４では定盤１１、
また、両面研磨機２８では上下定盤２１、２２の夫々表
面にポリシングパッドを装着し、この上に研磨液を供給
しポリシングする。この場合、合金製の定盤１１と上定
盤２１並びに下定盤２２を構成する合金の金属イオンの
溶出が起こるため、被研磨物表面が金属イオンにより汚
染されるという問題が生ずる。As the base metal of the surface plate 11 of the single-side polishing machine 14 and the upper surface plate 21 and the lower surface plate 22 of the double-side polishing machine 28, metal materials such as cast iron, stainless steel, and copper alloy have been conventionally used. For example, the single-side polishing machine 14 shown in FIG.
Alternatively, when the mirror polishing of the semiconductor wafer is performed using the double-side polishing machine 28 of FIG.
In the double-side polishing machine 28, polishing pads are mounted on the surfaces of the upper and lower stools 21 and 22, respectively, and a polishing liquid is supplied thereon to perform polishing. In this case, since the metal ions of the alloy constituting the surface plate 11, the upper surface plate 21, and the lower surface plate 22 of the alloy are eluted, there arises a problem that the surface of the object to be polished is contaminated by the metal ions.
【０００４】近年、ＩＣの高集積化に伴い、回路幅の微
細化が進み、シリコンウエハー等のＩＣ基板に要求され
る品質がますます高度化しており、研磨液を供給してポ
リシングする際の金属イオン汚染による性能への影響が
無視できなくなった。また研磨機用定盤に研磨液を供給
してポリシングする工程においては、パット面温度がシ
リコンウエハーの精度、生産性に重要な影響を与えるの
で厳密な温度コントロ−ルが必要となる。これらのため
に近い将来には、金属材料製定盤を用いた研磨機では被
研磨物の高度な品質要求に対応できなくなることが考え
られる。In recent years, as ICs have become more highly integrated, circuit widths have become finer, and the quality required for IC substrates such as silicon wafers has become more and more advanced. The effect on performance due to metal ion contamination can no longer be ignored. In the step of polishing by supplying a polishing liquid to a polishing machine surface plate, a strict temperature control is required because the pad surface temperature has an important effect on the accuracy and productivity of the silicon wafer. For these reasons, it is conceivable that a polishing machine using a metal material surface plate will not be able to meet the high quality requirements of the object to be polished in the near future.
【０００５】一方、特開平１−１１１８４２号公報に
は、研磨機用定盤を低熱膨張鋳鉄製にすることにより、
定盤寸法精度を高く維持し得ると言うことが開示されて
いる。しかしながら、このような低熱膨張鋳鉄製の定盤
においても、前述のような金属イオンの溶出に対しては
効果が余り期待できない。On the other hand, Japanese Patent Application Laid-Open No. 1-111842 discloses that a platen for a polishing machine is made of low thermal expansion cast iron.
It is disclosed that the dimensional accuracy of the platen can be maintained high. However, even with such a low-thermal-expansion cast iron platen, the effect on elution of metal ions as described above cannot be expected much.
【０００６】そのため、アルミナ等のセラミックス製の
定盤を用い、金属イオンによる汚染を防止することが一
部行われている。[0006] Therefore, it has been attempted to partially prevent contamination by metal ions by using a ceramic surface plate such as alumina.
【０００７】また、研磨機の定盤表面を有機系材料によ
り被覆する場合には、定盤の加工精度が不十分であると
いう問題がある。Further, when the surface of the surface plate of the polishing machine is coated with an organic material, there is a problem that the processing accuracy of the surface plate is insufficient.
【０００８】[0008]
【考案が解決しようとする課題】本考案は、前述のごと
く、研磨機の定盤に研磨液等を供給して被研磨物例えば
シリコンウエハー等のポリシングを行う場合に生ずる、
金属イオン等による汚染問題の解決並び定盤寸法精度を
高く維持しうる研磨機用定盤を提供することを目的とす
るものである。As described above, the present invention arises when a polishing liquid or the like is supplied to a surface plate of a polishing machine to perform polishing of an object to be polished such as a silicon wafer.
It is an object of the present invention to provide a polishing machine surface plate capable of solving the problem of contamination by metal ions and the like and maintaining the surface plate dimensional accuracy at a high level.
【０００９】[0009]
【課題を解決するための手段】本考案は、前述のような
問題点を解決するために、金属製研磨機用定盤の母材金
属の表面を封孔処理されたセラミックス層で被覆したも
のである。また、研磨機用定盤の母材金属が低熱膨張合
金から成ることを特徴とするものである。SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems by covering the surface of a base metal of a metal polishing table with a sealed ceramic layer. It is. Further, the base metal for the polishing machine surface plate is made of a low thermal expansion alloy.
【００１０】[0010]
【作用】本考案の研磨機用定盤においては、その母材金
属の表面が封孔処理されたセラミックス層で被覆されて
いるため、母材金属と被研磨物との間が絶縁され、研磨
液と母材の接触がなく、金属イオンの溶出を防止でき
る。In the polishing machine platen of the present invention, the surface of the base metal is covered with a ceramic layer which has been subjected to a sealing treatment, so that the base metal and the object to be polished are insulated and polished. Since there is no contact between the liquid and the base material, elution of metal ions can be prevented.
【００１１】さらに、研磨機用定盤の母材金属に、２０
〜１００℃間の平均膨張係数が６×１０-6／℃以下の低
熱膨張合金を適用すれば、研磨中の定盤寸法精度を高く
維持し得て、また、母材金属が封孔処理されたセラミッ
クス層を表面に備えているので、上記の効果とともに被
研磨物の寸法精度がより向上する。[0011] Further, the base metal of the polishing machine
If a low thermal expansion alloy having an average expansion coefficient of 6 × 10 −6 / ° C. or less between 100 ° C. and 100 ° C. is applied, the dimensional accuracy of the platen during polishing can be kept high, and the base metal is sealed. Since the ceramic layer is provided on the surface, the dimensional accuracy of the object to be polished is further improved in addition to the above effects.
【００１２】[0012]
【実施例】以下、図面を用いて実施例について説明す
る。図１は本考案の実施例による研磨機用定盤の断面図
である。図において、１は母材金属であって、鋳鉄、ス
テンレス、銅合金等の金属材料からなり、特に高い研磨
精度が必要な場合、低熱膨張合金を使用する。２は母材
金属１を被覆するセラミッスク層であり、アルミナ、酸
化クロム、チタニア等のセラミックスからなる。Embodiments will be described below with reference to the drawings. FIG. 1 is a sectional view of a polishing machine platen according to an embodiment of the present invention. In the drawing, reference numeral 1 denotes a base metal, which is made of a metal material such as cast iron, stainless steel, or a copper alloy. When particularly high polishing accuracy is required, a low thermal expansion alloy is used. Reference numeral 2 denotes a ceramic layer covering the base metal 1 and is made of ceramics such as alumina, chromium oxide, and titania.
【００１３】研磨機用定盤の母材金属表面へのセラミッ
クスの被覆法としては、母材金属１に及ぼす熱影響が小
さいこと、母材金属１との密着力が大きいこと、セラミ
ックス層２が緻密であることなどから、プラズマ溶射法
が好ましいが、これに準ずる方法でも被覆が可能であ
る。As a method of coating the surface of the base metal of the polishing machine with a ceramic, the thermal effect on the base metal 1 is small, the adhesion to the base metal 1 is large, and the ceramic layer 2 The plasma spraying method is preferred because of its denseness, but coating can also be performed by a method according to this method.
【００１４】図２は研磨機用定盤表面のセラミックス被
覆部の拡大図である。図２はセラミックスを例えばプラ
ズマ溶射のままの状態で被覆した例であり、３はセラミ
ックスで４は気孔である。図３は本発明の実施例の研磨
機用定盤表面へのセラミックス被覆部の拡大図であり、
セラミックス層２の気孔４を封孔材料５で封孔処理して
いる。FIG. 2 is an enlarged view of a ceramic coating portion on the surface of the polishing machine surface plate. FIG. 2 shows an example in which ceramics are coated, for example, in the state of plasma spraying, where 3 is ceramics and 4 is pores. FIG. 3 is an enlarged view of a ceramic coating portion on the surface of the surface plate for a polishing machine according to the embodiment of the present invention.
The pores 4 of the ceramic layer 2 are sealed with a sealing material 5.
【００１５】図２に示す例においては、セラミックス層
２のセラミックス３中には気孔４が存在している。セラ
ミックスの被覆を図２に示す様に行った研磨機用定盤で
も、金属イオンの溶出をある程度防止できるが、さらに
金属イオンの溶出を効果的に防ぐには、図３に示すよう
に、セラミックス層２の成膜後、封孔材料５中に定盤を
含浸して封孔処理を行い、セラミックス層２の気孔４を
埋めるようにするのがよい。In the example shown in FIG. 2, pores 4 are present in the ceramics 3 of the ceramics layer 2. Although a polishing machine surface plate coated with ceramics as shown in FIG. 2 can prevent the elution of metal ions to some extent, in order to further effectively prevent the elution of metal ions, as shown in FIG. After the formation of the layer 2, it is preferable to impregnate the platen into the sealing material 5 and perform a sealing treatment so as to fill the pores 4 of the ceramic layer 2.
【００１６】研磨工程での温度上昇は、通常１００℃以
下であるので、封孔材料５としては、エポキシ系、アク
リル系、フェノール系等の樹脂系材料を用いる。ただ
し、必要に応じて水ガラスあるいはシリコーン系樹脂等
の高耐熱材料を使用することもできる。Since the temperature rise in the polishing step is usually 100 ° C. or less, a resin material such as an epoxy-based material, an acrylic-based material, or a phenol-based material is used as the sealing material 5. However, a high heat-resistant material such as water glass or silicone resin can be used if necessary.
【００１７】つぎに、具体的な実施例について説明す
る。図４に示す片面研磨機１４を用いて、８インチシリ
コンウエハーをポリシングする例について述べる。この
片面研磨機用定盤１１としては、下記の表１に示す組成
の、Ｆｅ−Ｃｏ−Ｎｉ系低熱膨張合金製のφ１１５０m
m、厚さ４５mmのものを用いた。Next, a specific embodiment will be described. An example in which an 8-inch silicon wafer is polished using the single-side polishing machine 14 shown in FIG. 4 will be described. As the surface plate 11 for the single-side polishing machine, a φ1150 m made of Fe—Co—Ni-based low thermal expansion alloy having a composition shown in Table 1 below is used.
m and a thickness of 45 mm were used.
【００１８】[0018]
【表１】 上記の片面研磨機用として、定盤の母材金属２枚の全面
にプラズマ溶射により、Ａｌ2 Ｏ3 −２．５重量％Ｔｉ
Ｏ2 組成のセラミックスをプラズマ溶射法により被覆
し、セラミックス層２を形成した。試験１では、母材金
属表面にセラミックスを被覆したものを、エポキシ系樹
脂材５にて含浸して封孔処理を行った後、試験２では、
セラミックスを溶射のままの状態で使用面を所定プロフ
ァイルに研磨仕上げし、研磨機用定盤を製造した。な
お、試験３及び試験４では、比較例として夫々セラミッ
クス被覆のない低熱膨張合金製及び鋳鉄製の研磨機用定
盤Ａ及びＢを製造した。[Table 1] For the above-mentioned single-side polishing machine, Al 2 O 3 -2.5 wt% Ti is applied to the entire surface of the two base metal base plates by plasma spraying.
A ceramic having an O 2 composition was coated by a plasma spraying method to form a ceramic layer 2. In Test 1, after the base metal surface was coated with ceramics, and impregnated with an epoxy resin material 5 to perform a sealing treatment, in Test 2,
The surface to be used was polished and finished to a predetermined profile while the ceramics were sprayed as they were, thereby producing a surface plate for a polisher. In Tests 3 and 4, as comparative examples, platens A and B for polishing machines made of a low-thermal-expansion alloy and cast iron without a ceramic coating were manufactured, respectively.
【００１９】次に、ＪＩＳＨ８６６３の磁気膜厚計測定
法により、セラミックスの膜厚を測定した結果、いずれ
も使用面で平均２００μｍ、側面、底面その他では平均
１００μｍであった。Next, as a result of measuring the film thickness of the ceramics by a magnetic film thickness measuring method according to JIS 8663, the average was 200 μm on the use surface and 100 μm on the side and bottom surfaces.
【００２０】上記の研磨機用定盤を用いた研磨機１４
に、研磨液として、コロイダルシリカを供給して、シリ
コンウェハのポリシング研磨を行った。この場合の金属
イオンの溶出防止効果について、通常被膜評価試験とし
て用いられるＪＩＳＨ８６６６の有孔度試験法のうちフ
ェロキシル試験法により、定盤自体のそれぞれ３０ケ所
を調べた。その結果を表２に示す。Polishing machine 14 using the above-mentioned polishing machine surface plate
Then, colloidal silica was supplied as a polishing liquid, and polishing polishing of the silicon wafer was performed. In this case, the elution prevention effect of metal ions was examined at 30 places on the surface plate itself by the ferroxyl test method among the porosity test methods of JIS H 8666 usually used as a coating evaluation test. Table 2 shows the results.
【００２１】[0021]
【表２】 [Table 2]
【００２２】表２に示す如く、セラミックス被覆の無い
従来の研磨機用定盤Ａ，Ｂの場合（試験３及び４）の金
属イオンの溶出量に比較し、本考案のセラミックス被覆
でかつ封孔処理した研磨機用定盤の場合（試験１）は、
金属イオンの溶出が全然認められなかった。一方セラミ
ックス溶射のままの被覆の研磨機用定盤の場合（試験
１）も、従来の研磨機用定盤Ａ，Ｂの場合（試験３及び
４）よりは効果が認められた。尚、本実施例では、表１
に示すような組成の低熱膨張合金にて、研磨機用定盤を
製造したが、この合金に限定するものではない。以上の
如く、本考案の研磨機用定盤によれば、金属イオンの溶
出防止が可能になることが明らかである。As shown in Table 2, compared with the amounts of metal ions eluted in the case of the conventional polishing machines A and B without ceramic coating (Tests 3 and 4), the ceramic coating of the present invention and the sealing were performed. In the case of a treated polishing machine surface plate (Test 1),
No metal ions were eluted. On the other hand, in the case of the surface plate for the polishing machine with the coating as it was sprayed with the ceramics (Test 1), the effect was recognized as compared with the case of the conventional surface plates A and B for the polishing machine (Tests 3 and 4). In this embodiment, Table 1
Tables for polishing machines were manufactured using a low-thermal-expansion alloy having a composition as shown in Table 1. However, the present invention is not limited to this alloy. As described above, according to the polishing machine platen of the present invention, it is clear that elution of metal ions can be prevented.
【００２３】[0023]
【考案の効果】以上詳述したとおり、本考案の研磨機用
定盤においては、その母材金属の表面が封孔処理された
セラミックス層で被覆されているため、母材金属と被研
磨物との間が絶縁されて研磨液と母材の接触がなく、金
属イオンの溶出を防止でき、被研磨物の清浄度の向上に
大きく貢献することができる。また、母材金属として低
熱膨張合金を用いたので、上記効果に加えて研磨中の定
盤寸法精度を高く維持し得る。As described in detail above, in the polishing machine surface plate of the present invention, the surface of the base metal is covered with the ceramic layer which has been subjected to the sealing treatment. Are insulated from each other, so that there is no contact between the polishing liquid and the base material, elution of metal ions can be prevented, and it can greatly contribute to improvement in cleanliness of the object to be polished. Further, since a low thermal expansion alloy is used as the base metal, the dimensional accuracy of the surface plate during polishing can be kept high in addition to the above effects.
【図１】本考案の実施例による研磨機用定盤の断面図。FIG. 1 is a sectional view of a polishing machine platen according to an embodiment of the present invention.
【図２】比較例の研磨機用定盤表面へのセラミックス被
覆部の拡大図。FIG. 2 is an enlarged view of a ceramic coating portion on a surface of a polishing machine surface plate of a comparative example.
【図３】本発明の実施例の研磨機用定盤表面へのセラミ
ックス被覆部の拡大図。FIG. 3 is an enlarged view of a ceramic coating portion on a surface of a surface plate for a polishing machine according to an embodiment of the present invention.
【図４】片面研磨機の説明図。FIG. 4 is an explanatory view of a single-side polishing machine.
【図５】両面研磨機の説明図。FIG. 5 is an explanatory diagram of a double-side polishing machine.
１ 母材金属、２ セラミックス層、３ セラミック
ス、４ 気孔、５ 封孔材料、１１ 定盤、１２ 加圧
ヘッド、１３ ワ−ク、１４ 片面研磨機、２１ 上定
盤、２２ 下定盤、２３ 太陽ギヤ、２４ インタ−ナ
ルギヤ、２５ ドライバ−、２６ サブシリンダ−、２
７ メインシリンダ−、２８ 両面研磨機。1 Base metal, 2 ceramic layers, 3 ceramics, 4 pores, 5 sealing materials, 11 surface plate, 12 pressure head, 13 work, 14 single-side polishing machine, 21 upper surface plate, 22 lower surface plate, 23 sun Gear, 24 internal gear, 25 driver, 26 sub cylinder, 2
7 Main cylinder, 28 double-side polishing machine.
───────────────────────────────────────────────────── フロントページの続き (72)考案者 長橋 勲 東京都大田区西六郷４−30−３ スピー ドファム株式会社内 (56)参考文献 特開 平４−26117（ＪＰ，Ａ) 実開 昭62−11557（ＪＰ，Ｕ) (58)調査した分野(Int.Cl.6，ＤＢ名) B24B 37/04──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Isamu Nagahashi 4-30-3 Nishi-rokugo, Ota-ku, Tokyo Inside Speed Fam Co., Ltd. (56) References JP-A-4-26117 (JP, A) Shokai 62 -11557 (JP, U) (58) Fields investigated (Int. Cl. 6 , DB name) B24B 37/04
Claims (2)
ックス層を備えたことを特徴とする研磨機用定盤。1. A polishing machine platen, characterized in that it comprises a ceramic <br/> box layers sealing treatment on the surface of the base metal.
とを特徴とする請求項１記載の研磨機用定盤。2. The polishing table according to claim 1, wherein said base metal is made of a low thermal expansion alloy.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1991100376U JP2589064Y2 (en) | 1991-12-05 | 1991-12-05 | Surface plate for polishing machine |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1991100376U JP2589064Y2 (en) | 1991-12-05 | 1991-12-05 | Surface plate for polishing machine |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0549252U JPH0549252U (en) | 1993-06-29 |
| JP2589064Y2 true JP2589064Y2 (en) | 1999-01-20 |
Family
ID=14272313
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1991100376U Expired - Fee Related JP2589064Y2 (en) | 1991-12-05 | 1991-12-05 | Surface plate for polishing machine |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2589064Y2 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP6883475B2 (en) * | 2017-06-06 | 2021-06-09 | 株式会社荏原製作所 | Polishing table and polishing equipment equipped with it |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6211557U (en) * | 1985-07-04 | 1987-01-24 | ||
| JPH0426117A (en) * | 1990-05-22 | 1992-01-29 | Kawasaki Steel Corp | Lapping apparatus for semiconductor wafer |
-
1991
- 1991-12-05 JP JP1991100376U patent/JP2589064Y2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0549252U (en) | 1993-06-29 |
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