JP2001031466A - Corrosion-resistant ceramic member - Google Patents
Corrosion-resistant ceramic memberInfo
- Publication number
- JP2001031466A JP2001031466A JP20716299A JP20716299A JP2001031466A JP 2001031466 A JP2001031466 A JP 2001031466A JP 20716299 A JP20716299 A JP 20716299A JP 20716299 A JP20716299 A JP 20716299A JP 2001031466 A JP2001031466 A JP 2001031466A
- Authority
- JP
- Japan
- Prior art keywords
- oxide
- aluminum oxide
- corrosion
- halogen
- ceramic member
- 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.)
- Pending
Links
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、半導体デバイス製
造工程等に好適な、ハロゲン系腐蝕ガスまたはハロゲン
ガスプラズマに対する耐性の高い耐食性セラミックス部
材に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a corrosion-resistant ceramic member having high resistance to a halogen-based corrosive gas or a halogen gas plasma, which is suitable for a semiconductor device manufacturing process or the like.
【０００２】[0002]
【従来の技術】半導体デバイス製造工程においては、化
学的腐蝕性の高い環境下で用いられる部材が多い。この
ような部材としては、例えば、ベルジャー、チャンバ
ー、サセプター、クランプリング、フォーカスリング等
を挙げることができ、これらは例えば腐蝕性の高いハロ
ゲン系ガスによるドライエッチング工程で使用されるた
め、ハロゲンガスプラズマ環境下での耐食性が高いこと
が要求される。2. Description of the Related Art In a semiconductor device manufacturing process, many members are used in an environment having high chemical corrosion. Examples of such a member include a bell jar, a chamber, a susceptor, a clamp ring, and a focus ring. These members are used in a dry etching process using a highly corrosive halogen-based gas. High corrosion resistance in the environment is required.
【０００３】従来、この種の部材として石英ガラス（Ｓ
ｉＯ２）やアルミナ焼結体（Ａｌ２Ｏ３）が用いられて
きたが、ハロゲンガスプラズマ環境下での耐食性が十分
ではなく、これらに代わって希土類元素を含む複合酸化
物を用いることが検討されている。Conventionally, quartz glass (S
Although iO 2 ) and sintered alumina (Al 2 O 3 ) have been used, their corrosion resistance in a halogen gas plasma environment is not sufficient, and the use of a composite oxide containing a rare earth element in place of them has been studied. Have been.
【０００４】[0004]
【発明が解決しようとする課題】しかしながら、このよ
うな希土類元素を含む複合酸化物にも以下のような問題
がある。すなわちＹ２Ｏ３に代表される希土類酸化物を
含む複合酸化物はいずれも誘電損失が大きく、装置のマ
ッチングがとりにくいことや、損失による発熱により連
続使用時の破損が懸念される。However, such a composite oxide containing a rare earth element also has the following problems. That is, any of the composite oxides including rare earth oxides represented by Y 2 O 3 has a large dielectric loss, and it is difficult to match the devices, and there is a concern that the heat generated by the loss may cause damage during continuous use.
【０００５】本発明はかかる事情に鑑みてなされたもの
であって、ハロゲン系腐蝕ガスまたはハロゲンガスプラ
ズマに対する耐性が高く、しかも誘電損失が小さい耐食
性セラミックス部材を提供することを目的とする。The present invention has been made in view of such circumstances, and has as its object to provide a corrosion-resistant ceramic member having a high resistance to a halogen-based corrosive gas or a halogen gas plasma and a small dielectric loss.
【０００６】[0006]
【課題を解決するための手段】本発明者らは、上記課題
を解決すべく研究を重ねた結果、ハロゲン系腐蝕ガスあ
るいはそれらのプラズマに曝される部位を、酸化イット
リウムおよび酸化アルミニウムを所定の比率で含有し、
Ｘ線回折によりα−Ａｌ２Ｏ３の結晶相が検出されない
ようにすることにより、ハロゲン系腐蝕ガスあるいはそ
れらのプラズマに対する耐食性が高いものとなり、さら
に、これに微量の酸化ケイ素を添加することにより誘電
損失が改善することを見出し本発明を完成するに至っ
た。Means for Solving the Problems As a result of repeated studies to solve the above-mentioned problems, the present inventors found that a portion exposed to a halogen-based corrosive gas or their plasma was converted to yttrium oxide and aluminum oxide by a predetermined amount. Contained in proportions,
By preventing the crystal phase of α-Al 2 O 3 from being detected by X-ray diffraction, the corrosion resistance to halogen-based corrosive gases or their plasma becomes high, and by adding a small amount of silicon oxide to this, The inventors have found that the dielectric loss is improved, and have completed the present invention.
【０００７】すなわち、本発明は、ハロゲン系腐蝕ガス
あるいはそれらのプラズマに曝される部位が、酸化イッ
トリウム、酸化アルミニウム、および酸化ケイ素からな
り、酸化イットリウム：酸化アルミニウムの重量比が５
７．０：４３．０〜５８．０：４２．０の範囲であり、
酸化ケイ素は、酸化イットリウムと酸化アルミニウムの
合計量に対して０．１５〜０．５重量％の範囲で含有
し、Ｘ線回折によりα−Ａｌ２Ｏ３の結晶相が検出され
ないことを特徴とする耐食性セラミックス部材を提供す
るものである。That is, according to the present invention, a portion exposed to a halogen-based corrosive gas or a plasma thereof is made of yttrium oxide, aluminum oxide, and silicon oxide, and the weight ratio of yttrium oxide: aluminum oxide is 5%.
7.0: 43.0 to 58.0: 42.0,
Silicon oxide is contained in a range of 0.15 to 0.5% by weight based on the total amount of yttrium oxide and aluminum oxide, and a crystal phase of α-Al 2 O 3 is not detected by X-ray diffraction. The present invention is to provide a corrosion-resistant ceramic member as described above.
【０００８】[0008]
【発明の実施の形態】以下、本発明について具体的に説
明する。本発明のセラミックス部材は、ハロゲン系腐蝕
ガスあるいはそれらのプラズマに曝される部位が、酸化
イットリウム（イットリア；Ｙ２Ｏ３）および酸化アル
ミニウム（アルミナ；Ａｌ２Ｏ３）を主体とし、酸化イ
ットリウム：酸化アルミニウムの重量比が５７．０：４
３．０〜５８．０：４２．０の範囲である。このよう
に、酸化イットリウムおよび酸化アルミニウムを主体と
することにより、ハロゲン系腐蝕ガスあるいはそれらの
プラズマに対する耐性を高いものとすることができる。BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described specifically. In the ceramic member of the present invention, a portion exposed to a halogen-based corrosive gas or a plasma thereof is mainly composed of yttrium oxide (yttria; Y 2 O 3 ) and aluminum oxide (alumina; Al 2 O 3 ). Aluminum oxide weight ratio of 57.0: 4
3.0 to 58.0: 42.0. As described above, by using yttrium oxide and aluminum oxide as main components, the resistance to halogen-based corrosive gas or plasma thereof can be increased.
【０００９】酸化イットリウム：酸化アルミニウムの重
量比が５７．０：４３．０〜５８．０：４２．０の範囲
としたのは、この範囲よりも酸化アルミニウムが多くな
ると、α−Ａｌ２Ｏ３相が偏析し、このα−Ａｌ２Ｏ３
相はハロゲンガスに対し十分な耐食性を持たないため耐
食性が低下するからであり、一方、この範囲よりも酸化
イットリウムが多くなると不均一組織となり腐蝕ムラが
発生し、パーティクルの発生が多くなるからである。酸
化イットリウム：酸化アルミニウムの重量比がこの範囲
内であれば、これらの複合酸化物、例えばイットリウム
−アルミニウム−ガーネット（ＹＡＧ）が形成される。The weight ratio of yttrium oxide: aluminum oxide is set in the range of 57.0: 43.0 to 58.0: 42.0. When the amount of aluminum oxide exceeds this range, α-Al 2 O 3 The phase is segregated, and the α-Al 2 O 3
This is because the phase does not have sufficient corrosion resistance to the halogen gas, so that the corrosion resistance is reduced.On the other hand, if the yttrium oxide is more than this range, a non-uniform structure is formed, resulting in uneven corrosion and increased generation of particles. is there. When the weight ratio of yttrium oxide: aluminum oxide is within this range, these composite oxides, for example, yttrium-aluminum-garnet (YAG) are formed.
【００１０】酸化イットリウム：酸化アルミニウムの重
量比が上記範囲内であってもＸ線回折的にα−Ａｌ２Ｏ
３相が検出される場合があるが、α−Ａｌ２Ｏ３相はＹ
ＡＧに代表される酸化イットリウムと酸化アルミニウム
との複合酸化物相に比較して耐食性が劣り、パーティク
ル発生の原因となるので好ましくない。Even when the weight ratio of yttrium oxide: aluminum oxide is within the above range, X-ray diffraction indicates that α-Al 2 O
Although three phases may be detected, α-Al 2 O 3 phase is Y
As compared with the composite oxide phase of yttrium oxide and aluminum oxide represented by AG, the corrosion resistance is inferior and it is not preferable because it causes the generation of particles.
【００１１】本発明のセラミックス部材は、上記酸化イ
ットリウムおよび酸化アルミニウムの他に酸化ケイ素
（ＳｉＯ２）を、酸化イットリウムおよび酸化アルミニ
ウムの合計量に対し外部添加で０．１５〜０．５重量％
添加する。The ceramic member according to the present invention is characterized in that, in addition to the above yttrium oxide and aluminum oxide, 0.15 to 0.5% by weight of silicon oxide (SiO 2 ) is added externally to the total amount of yttrium oxide and aluminum oxide.
Added.
【００１２】酸化ケイ素は、誘電損失を低下させるため
に重要な元素であり、酸化イットリウムおよび酸化アル
ミニウムの合計量に対し上述の範囲で添加することによ
り、誘電損失を適切な範囲とすることができる。Silicon oxide is an important element for reducing the dielectric loss. The dielectric loss can be adjusted to an appropriate range by adding silicon oxide in the above range with respect to the total amount of yttrium oxide and aluminum oxide. .
【００１３】しかし、酸化ケイ素が０．１５重量％未満
では、誘電損失を低下させる効果が十分に発揮されず、
誘電損失が高いものとなってしまう。逆に、酸化ケイ素
が０．５重量％を超えた場合には誘電損失を低下させる
効果が飽和するばかりか、耐食性が低下してしまう。However, if the content of silicon oxide is less than 0.15% by weight, the effect of reducing the dielectric loss cannot be sufficiently exhibited.
The dielectric loss is high. Conversely, if the amount of silicon oxide exceeds 0.5% by weight, the effect of reducing the dielectric loss is saturated, and the corrosion resistance is reduced.
【００１４】以上のように、本発明のセラミックス部材
は、ハロゲン系腐蝕ガスあるいはそれらのプラズマに曝
される部位を、酸化イットリウムおよび酸化アルミニウ
ムを主体とし、これらの重量比を５７．０：４３．０〜
５８．０：４２．０の範囲とし、これに酸化ケイ素を酸
化イットリウムと酸化アルミニウムの合計量に対して
０．１５〜０．５重量％の範囲で含有させ、さらにＸ線
回折によりα−Ａｌ２Ｏ ３の結晶相が検出されないよう
にしたので、ハロゲン系腐蝕ガスまたはハロゲンガスプ
ラズマに対する耐性が高く、しかも誘電損失が小さい。As described above, the ceramic member of the present invention
Exposed to halogenated corrosive gases or their plasma
Parts to be treated are yttrium oxide and aluminum oxide
And their weight ratio is 57.0: 43.0-
58.0: 42.0, to which silicon oxide was added
To the total amount of yttrium oxide and aluminum oxide
0.15 to 0.5% by weight of X-ray
Α-Al by diffraction2O 3So that the crystal phase of
The halogen-based corrosion gas or halogen gas pump.
High resistance to plasma and low dielectric loss.
【００１５】[0015]
【実施例】以下、本発明の実施例について説明する。純
度９９．９％以上の酸化イットリウム（Ｙ２Ｏ３）と純
度９９．９％以上の酸化アルミニウム（Ａｌ２Ｏ３）を
合計２００ｇ秤量し、これらをイオン交換水２００ｇお
よび鉄芯入りナイロンボール２５０ｇとともにポリエチ
レンポット中に装入し、さらに添加剤として所定量のＳ
ｉＯ２を添加し、１６時間混合した。得られたスラリー
をロータリーエバポレーターで減圧乾燥した後、得られ
た粉末を＃１００のナイロンメッシュを用いてメッシュ
パスを行った。この粉末を直径１５ｍｍ、厚さ６ｍｍに
成形した後、冷間静水圧プレス成形して成形体を得た。
得られた成形体を大気雰囲気の電気炉中で、所定温度４
時間の焼成を行った。Embodiments of the present invention will be described below. A total of 200 g of yttrium oxide (Y 2 O 3 ) having a purity of 99.9% or more and aluminum oxide (Al 2 O 3 ) having a purity of 99.9% or more were weighed, and 200 g of ion-exchanged water and 250 g of an iron cored nylon ball were weighed. Together with a predetermined amount of S as an additive.
The iO 2 was added and mixed for 16 hours. After the obtained slurry was dried under reduced pressure by a rotary evaporator, the obtained powder was subjected to a mesh pass using a # 100 nylon mesh. This powder was formed into a diameter of 15 mm and a thickness of 6 mm, and then cold isostatically pressed to obtain a formed body.
The obtained molded body is heated at a predetermined temperature of 4 in an electric furnace in an air atmosphere.
Time firing was performed.
【００１６】得られた焼結体の表面のＸ線回折を行い、
かつ誘電損失の測定を行った。また、焼結体の片面を鏡
面研磨し、平行平板型ＲＩＥエッチング装置のチャンバ
ー内に装入し、ＣＦ４＋Ｏ２のプラズマによる腐蝕試験
を行った。その際、研磨面の一部をポリイミドテープで
マスクし、マスクのある部分とない部分の段差を測定す
ることによりエッチング速度を算出した。また、チャン
バー内のウエハ上のパーティクル数を測定した。表１に
これらの結果を示す。The surface of the obtained sintered body is subjected to X-ray diffraction,
In addition, the dielectric loss was measured. One side of the sintered body was mirror-polished, placed in a chamber of a parallel plate type RIE etching apparatus, and subjected to a corrosion test using CF 4 + O 2 plasma. At this time, a part of the polished surface was masked with a polyimide tape, and the etching rate was calculated by measuring the level difference between the portion with and without the mask. Further, the number of particles on the wafer in the chamber was measured. Table 1 shows these results.
【００１７】表１に示すように、本発明の範囲内の実施
例であるＮｏ．１，２は、十分に緻密化しており、Ｘ線
的にα−Ａｌ２Ｏ３相も検出されず、エッチング速度も
２〜３ｎｍ／ｍｉｎと極めて小さな値を示し、誘電損失
も低い値を示した。As shown in Table 1, No. 1 which is an embodiment within the scope of the present invention. Samples 1 and 2 are sufficiently densified, no α-Al 2 O 3 phase is detected by X-ray, the etching rate shows a very small value of 2 to 3 nm / min, and the dielectric loss shows a low value. Was.
【００１８】これに対して、ＳｉＯ２の添加量が本発明
の範囲外のＮｏ．３〜６のうち、添加量が少ないＮｏ．
３，５では誘電損失が高く、添加量の多いＮｏ．４，６
では耐エッチング性が低下することが確認された。On the other hand, when the amount of added SiO 2 is out of the range of the present invention, No. Among Nos. 3 to 6, the addition amount was small.
In Nos. 3 and 5, the dielectric loss was high, and in Nos. 4,6
It was confirmed that the etching resistance was lowered.
【００１９】酸化イットリウムと酸化アルミニウムとの
重量比が本発明の範囲ではあるが、Ｘ線回折によりα−
Ａｌ２Ｏ３相が検出されたＮｏ．７ではパーティクル数
が多く、不適であることが確認された。Although the weight ratio of yttrium oxide to aluminum oxide is within the scope of the present invention, α-
No. 2 in which the Al 2 O 3 phase was detected. In No. 7, the number of particles was large, and it was confirmed that the particles were unsuitable.
【００２０】酸化イットリウムと酸化アルミニウムとの
重量比が本発明において規定する範囲よりも酸化アルミ
ニウムリッチ側に外れるＮｏ．８ではエッチング速度が
高く、また、酸化イットリウムリッチ側に外れるＮｏ．
９ではパーティクル数が多いことが確認された。In the case of No. 3 in which the weight ratio between yttrium oxide and aluminum oxide deviates from the range specified in the present invention to the aluminum oxide-rich side. In No. 8, the etching rate was high, and No. 8 deviated to the yttrium oxide rich side.
In No. 9, it was confirmed that the number of particles was large.
【００２１】[0021]
【表１】 [Table 1]
【００２２】[0022]
【発明の効果】以上説明したように、本発明によれば、
ハロゲン系腐蝕ガスあるいはそれらのプラズマに曝され
る部位を、酸化イットリウムおよび酸化アルミニウムを
主体とし、これらの重量比を５７．０：４３．０〜５
８．０：４２．０の範囲とし、これに酸化ケイ素を酸化
イットリウムと酸化アルミニウムの合計量に対して０．
１５〜０．５重量％の範囲で含有させ、さらにＸ線回折
によりα−Ａｌ２Ｏ３の結晶相が検出されないようにし
たので、ハロゲン系腐蝕ガスまたはハロゲンガスプラズ
マに対する耐性が高く、しかも誘電損失が小さい耐食性
セラミックス部材を得ることができる。As described above, according to the present invention,
The portion exposed to the halogen-based corrosive gas or their plasma is mainly composed of yttrium oxide and aluminum oxide, and their weight ratio is 57.0: 43.0 to 53.0.
8.0: 42.0, and silicon oxide is added to the total amount of yttrium oxide and aluminum oxide.
Since it is contained in the range of 15 to 0.5% by weight and the crystal phase of α-Al 2 O 3 is not detected by X-ray diffraction, the resistance to the halogen-based corrosive gas or the halogen gas plasma is high and the dielectric constant is high. A corrosion-resistant ceramic member with small loss can be obtained.
フロントページの続き (72)発明者 大滝 浩通 宮城県仙台市泉区明通三丁目５番 株式会 社日本セラテック本社工場内 (72)発明者 岸 幸男 宮城県仙台市泉区明通三丁目５番 株式会 社日本セラテック本社工場内 Ｆターム(参考） 4G031 AA08 AA29 AA30 BA26 CA01 5F004 AA16 BB21 BB29 DA00 Continuing on the front page (72) Inventor Hiromichi Otaki 3-5-Mesudori, Izumi-ku, Sendai-shi, Miyagi Prefecture Inside the Japan Ceratech headquarters and factory (72) Inventor Yukio Kishi 3--5, Meido, Izumi-ku, Sendai-shi, Miyagi F-term in the Japan Ceratech headquarters factory (reference) 4G031 AA08 AA29 AA30 BA26 CA01 5F004 AA16 BB21 BB29 DA00
Claims (1)
ラズマに曝される部位が、酸化イットリウム、酸化アル
ミニウム、および酸化ケイ素からなり、酸化イットリウ
ム：酸化アルミニウムの重量比が５７．０：４３．０〜
５８．０：４２．０の範囲であり、酸化ケイ素は、酸化
イットリウムと酸化アルミニウムの合計量に対して０．
１５〜０．５重量％の範囲で含有し、Ｘ線回折によりα
−Ａｌ ２Ｏ３の結晶相が検出されないことを特徴とする
耐食性セラミックス部材。Claims: 1. A halogen-based corrosive gas or a gas comprising
Sites exposed to plasma are yttrium oxide and aluminum oxide
Minium and silicon oxide, yttrium oxide
Weight ratio of aluminum oxide: 57.0: 43.0 to
58.0: 42.0, and the silicon oxide
0.1 based on the total amount of yttrium and aluminum oxide.
Contained in the range of 15 to 0.5% by weight.
-Al 2O3Characterized in that no crystalline phase is detected
Corrosion resistant ceramic members.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP20716299A JP2001031466A (en) | 1999-07-22 | 1999-07-22 | Corrosion-resistant ceramic member |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP20716299A JP2001031466A (en) | 1999-07-22 | 1999-07-22 | Corrosion-resistant ceramic member |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JP2001031466A true JP2001031466A (en) | 2001-02-06 |
Family
ID=16535263
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP20716299A Pending JP2001031466A (en) | 1999-07-22 | 1999-07-22 | Corrosion-resistant ceramic member |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2001031466A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7407904B2 (en) | 2005-07-15 | 2008-08-05 | Toto Ltd. | Yttria sintered body and corrosion-resistant material, and manufacturing method |
| JP2010174325A (en) * | 2009-01-29 | 2010-08-12 | Kyocera Corp | Discharge electrode unit, discharge electrode assembly and discharge treatment apparatus |
| KR101087514B1 (en) * | 2006-09-11 | 2011-11-28 | 가부시키가이샤 알박 | Dry etching method |
| WO2023162743A1 (en) * | 2022-02-26 | 2023-08-31 | Toto株式会社 | Composite structure and semiconductor manufacturing device having composite structure |
-
1999
- 1999-07-22 JP JP20716299A patent/JP2001031466A/en active Pending
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7407904B2 (en) | 2005-07-15 | 2008-08-05 | Toto Ltd. | Yttria sintered body and corrosion-resistant material, and manufacturing method |
| US7566675B2 (en) | 2005-07-15 | 2009-07-28 | Toto Ltd. | Corrosion-resistant material manufacturing method |
| KR101087514B1 (en) * | 2006-09-11 | 2011-11-28 | 가부시키가이샤 알박 | Dry etching method |
| JP2010174325A (en) * | 2009-01-29 | 2010-08-12 | Kyocera Corp | Discharge electrode unit, discharge electrode assembly and discharge treatment apparatus |
| WO2023162743A1 (en) * | 2022-02-26 | 2023-08-31 | Toto株式会社 | Composite structure and semiconductor manufacturing device having composite structure |
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