JPH0436727B2 - - Google Patents
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- Publication number
- JPH0436727B2 JPH0436727B2 JP62126701A JP12670187A JPH0436727B2 JP H0436727 B2 JPH0436727 B2 JP H0436727B2 JP 62126701 A JP62126701 A JP 62126701A JP 12670187 A JP12670187 A JP 12670187A JP H0436727 B2 JPH0436727 B2 JP H0436727B2
- Authority
- JP
- Japan
- Prior art keywords
- dry etching
- pump
- exhaust gas
- vacuum pump
- adsorbent
- 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
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- Treating Waste Gases (AREA)
- Drying Of Semiconductors (AREA)
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明はガリウム・ヒ素ウエハーをドライエツ
チングする際に発生する排ガス中の有害なガリウ
ム（以下Gaと記す）およびヒ素（以下Asと記
す）塩化物、フツ化物が真空ポンプ内に付着する
のを防止し、かつ排ガス中の上記有害物を吸着除
去するドライエツチング排ガスの処理方法に関す
る。[Detailed Description of the Invention] [Industrial Application Field] The present invention is directed to the removal of harmful gallium (hereinafter referred to as Ga) and arsenic (hereinafter referred to as As) chloride in the exhaust gas generated when dry etching gallium arsenide wafers. The present invention relates to a method for treating dry etching exhaust gas, which prevents substances and fluorides from adhering to the inside of a vacuum pump, and adsorbs and removes the harmful substances in the exhaust gas.
近年、超高速演算用等の半導体素子の基板とし
てGa・Asウエハーの使用量が著しく増加し、さ
らに、その集積回路の微細化も高まるばかりで、
そのエツチング工程はドライエツチング化の方向
にある。
In recent years, the amount of Ga/As wafers used as substrates for semiconductor devices for ultra-high-speed calculations has increased significantly, and the miniaturization of integrated circuits has also continued to increase.
The etching process is moving toward dry etching.
また、Ga・Asウエハーのドライエツチングに
おいては、基板を貫通する微細な孔を穿設する
等、Ga・Asウエハーを直接エツチングによつて
加工する工程があり、この場合、例えばCCl2F2
等のように塩素、フツ素を含有するガスが用いら
れる。 In dry etching of Ga/As wafers, there is a process in which the Ga/As wafer is directly etched, such as by drilling fine holes penetrating the substrate .
Gases containing chlorine and fluorine are used, such as chlorine and fluorine.
したがつて、Ga・Asウエハーのドライエツチ
ング排ガス中には、GaおよびAsの塩化物、フツ
化物が生成含有される。これらのガスは人体に有
害で、加水分解して強酸性を示すなど危険なガス
であつて、大気中に放出するには、これらを除去
しなければならない。 Therefore, chlorides and fluorides of Ga and As are produced and contained in the exhaust gas from dry etching of Ga/As wafers. These gases are harmful to the human body and become strongly acidic when hydrolyzed, so they must be removed before they can be released into the atmosphere.
そのため、従来ドライエツチング排ガスを苛性
ソーダ等のアルカリ性水溶液で洗浄し、上記有害
物を除去する湿式除去法が採用されている。 Therefore, conventionally, a wet removal method has been adopted in which the dry etching exhaust gas is washed with an alkaline aqueous solution such as caustic soda to remove the harmful substances.
また、Ga・Asウエハーのドライエツチング
は、減圧下で行なわれるため、ドライエツチング
室には、拡散ポンプ、メカニカルブースターポン
プ、ターボ分子ポンプ、油圧回路ポンプ、ドライ
真空ポンプが適宜組合わされた減圧排気系が接続
されておりドライエツチング排ガスは、これらポ
ンプによつて構成された排気系を通つて放出され
る。この際、特に油回転ポンプ、ドライ真空ポン
プ内に、GaおよびAsの塩化物、フツ化物が堆積
するので、これらポンプのメンテナンスは極めて
危険な作業となつている。 In addition, since dry etching of Ga/As wafers is performed under reduced pressure, the dry etching chamber is equipped with a reduced pressure exhaust system that is appropriately combined with a diffusion pump, mechanical booster pump, turbo molecular pump, hydraulic circuit pump, and dry vacuum pump. are connected, and the dry etching exhaust gas is discharged through an exhaust system constituted by these pumps. At this time, Ga and As chlorides and fluorides are deposited particularly in oil rotary pumps and dry vacuum pumps, making maintenance of these pumps extremely dangerous.
しかし、上記湿式除去法は、洗浄に用いたアル
カリ水溶液中に、Ga化合物、As化合物が捕集、
含有されるため、この廃液の処理に手間がかか
る。
However, in the above wet removal method, Ga compounds and As compounds are collected in the alkaline aqueous solution used for cleaning.
Because of this, it takes time and effort to treat this waste liquid.
また、排気系に対しては、三塩化ホウ素を含む
ドライエツチング排ガスについては、既に発表
（特公昭61−16492号公報）されているにもかかわ
らず、GaおよびAsの塩化物、フツ化物の堆積を
防止する対策は未だなく、作業員は危険、かつ頻
繁なメンテナンス作業を行なつているのが現状で
ある。 In addition, regarding the exhaust system, although it has already been announced (Japanese Patent Publication No. 16492/1983) that dry etching exhaust gas containing boron trichloride is not allowed to accumulate, Ga and As chlorides and fluorides are deposited. Currently, there are no measures to prevent this, and workers are currently performing dangerous and frequent maintenance work.
本発明は上記の事情に鑑み、真空ポンプ内に
GaおよびAsの塩化物、フツ化物が堆積するのを
防止し、メンテナンス作業を軽減するとともに排
ガス中の有害物を除去するドライエツチング排ガ
スの処理方法を提供することを目的とする。 In view of the above circumstances, the present invention has been developed to provide a
The object of the present invention is to provide a method for treating dry etching exhaust gas that prevents the accumulation of Ga and As chlorides and fluorides, reduces maintenance work, and removes harmful substances in the exhaust gas.
本発明は上記の目的を達成すべくなされたもの
で、その要旨は、塩素およびフツ素を含むガスを
用いてガリウム・ヒ素ウエハーをドライエツチン
グする際に、ドライエツチング排ガス中に含まれ
るガリウムおよびヒ素の塩化物、フツ化物が真空
ポンプ内に堆積することを防止するため、真空ポ
ンプ内に不活性ガスを導入する手段と、真空ポン
プを加熱する手段とを有し、かつ上記真空ポンプ
の排気ガスを、吸着剤に通して含有する有害物を
除去することを特徴とするガリウム・ヒ素ウエハ
ーのドライエツチング排ガスの処理方法にある。
The present invention has been made to achieve the above object, and its gist is to remove gallium and arsenic contained in the dry etching exhaust gas when dry etching gallium arsenide wafers using a gas containing chlorine and fluorine. In order to prevent chlorides and fluorides from accumulating in the vacuum pump, the vacuum pump includes means for introducing an inert gas into the vacuum pump, and means for heating the vacuum pump, and also includes means for introducing an inert gas into the vacuum pump, and a means for heating the vacuum pump. A method for treating exhaust gas from dry etching of gallium arsenide wafers, which comprises passing through an adsorbent to remove harmful substances contained therein.
排気系の真空ポンプには、GaおよびAsの塩化
物、フツ化物の堆積を防止する機構が設けられて
いるので、真空ポンプ内の堆積が防止され、メン
テナンスの負担が格段に減少され、また、排ガス
中の有害物は、吸着除去されるので、処理が容易
となる。
The exhaust system vacuum pump is equipped with a mechanism to prevent the accumulation of Ga and As chlorides and fluorides, which prevents accumulation inside the vacuum pump and greatly reduces the burden of maintenance. Harmful substances in the exhaust gas are removed by adsorption, making treatment easier.
第１図および第２図は本発明の処理法を実施す
る装置の一例を示すもので、図中符号１はドライ
エツチング室である。ドライエツチング室１に
は、Ga.Asウエハー２をエツチングするドライエ
ツチングガス３が導入されるとともに拡散ポン
プ、メカニカルブースタポンプ或はターボ分子ポ
ンプ４と油回転ポンプ或はドライ真空ポンプ５と
を適宜組合わせた排気系６が接続され、ドライエ
ツチング室１を真空に保持している。上記油回転
ポンプ或はドライ真空ポンプには、後述するGa
およびAsの塩化物、フツ化物の堆積を防止する
機構１０が設けられている。
1 and 2 show an example of an apparatus for carrying out the processing method of the present invention, and reference numeral 1 in the figures indicates a dry etching chamber. A dry etching gas 3 for etching the Ga.As wafer 2 is introduced into the dry etching chamber 1, and a diffusion pump, a mechanical booster pump, or a turbo molecular pump 4 and an oil rotary pump or a dry vacuum pump 5 are appropriately assembled. A combined exhaust system 6 is connected to maintain the dry etching chamber 1 in a vacuum. The above-mentioned oil rotary pump or dry vacuum pump is equipped with Ga, which will be described later.
A mechanism 10 for preventing the deposition of chlorides and fluorides of As is provided.
また上記排気系６の出口ライン７にあ、Gaお
よびAsの塩化物、フツ化物等の有害物を吸着除
去する吸着剤８が充填された吸着塔９が設けられ
ている。 Further, an adsorption tower 9 filled with an adsorbent 8 for adsorbing and removing harmful substances such as Ga and As chlorides and fluorides is provided in the outlet line 7 of the exhaust system 6.
上記堆積防止機構１０は次のように構成されて
いる。すなわち、第２図に示すように油回転ポン
プ或はドライ真空ポンプ５には、ケーシング５ａ
が設けられ、真空ポンプオイル、および排ガス中
の塩素化合物、フツ素化合物に不活性な、完全に
乾燥された不活性ガス（例えばN2等）１１がパ
ージ導入ライン１２を介して接続されており、こ
の不活性ガスは導出ライン１２ａより放出されポ
ンプ５が上記不活性ガス１１の雰囲気内に保持さ
れるとともに、その少量がポンプ５内に連続導入
され、出口ライン７より放出されるようになつて
いる。さらに、上記機構に加えて、ポンプ５を加
熱する加熱機構１３を設け、塩素化合物、フツ素
化合物の堆積を防止してもよい。また、ポンプ５
に入る前の排ガスラインを若干加熱し、その後冷
却面を有するダストトラツプを設け、蒸気圧の低
い成分をポンプ５の前で除去してもよい。 The deposition prevention mechanism 10 is constructed as follows. That is, as shown in FIG. 2, the oil rotary pump or dry vacuum pump 5 has a casing 5a.
A completely dried inert gas (for example, N2, etc.) 11 that is inert to vacuum pump oil and chlorine compounds and fluorine compounds in the exhaust gas is connected via a purge introduction line 12. This inert gas is discharged from the outlet line 12a and the pump 5 is held in the atmosphere of the inert gas 11, and a small amount of the inert gas is continuously introduced into the pump 5 and discharged from the outlet line 7. ing. Furthermore, in addition to the above mechanism, a heating mechanism 13 for heating the pump 5 may be provided to prevent the deposition of chlorine compounds and fluorine compounds. Also, pump 5
The exhaust gas line before entering the exhaust gas line may be slightly heated and then a dust trap with cooling surfaces may be provided to remove components with low vapor pressure before the pump 5.
上記堆積防止機構１０を設けることによつて、
GaおよびAsの塩化物、フツ化物の堆積は防止さ
れ、堆積によるポンプのメンテナンスの頻度、危
険性は、格段に減少する。 By providing the above-mentioned deposition prevention mechanism 10,
The accumulation of Ga and As chlorides and fluorides is prevented, and the frequency and danger of pump maintenance due to accumulation are significantly reduced.
また、吸着塔９に充填される吸着剤は、活性
炭、モレキユラシーブス4A・5A・13X、シリカ
ゲル、天然ゼオライト、ケイ藻土、酸化マグネシ
ウム、等通常の吸着剤がいずれも使用出来る。ま
た、吸着塔９は、複数塔設け、切換え使用される
が、有害物を吸着した使用ずみの吸着剤は、回収
の上一括して適正処理される。 Further, as the adsorbent to be filled in the adsorption tower 9, any ordinary adsorbent such as activated carbon, Molecular Sieves 4A, 5A, 13X, silica gel, natural zeolite, diatomaceous earth, magnesium oxide, etc. can be used. In addition, although a plurality of adsorption towers 9 are provided and used selectively, the used adsorbent that has adsorbed harmful substances is recovered and properly disposed of all at once.
また、吸着剤として、上記吸着剤に水を吸着さ
せたものを用い、GaおよびAsの塩化物、フル化
物を、Gaの酸化物、或は亜ヒ酸として除去して
もよい。 Alternatively, the above-mentioned adsorbent with water adsorbed thereon may be used as the adsorbent, and chlorides and fluorides of Ga and As may be removed as Ga oxides or arsenous acid.
実施例 １
平行平板型ドライエツチング装置を用い、ドラ
イエツエツチングガスとして、CCl2F2およびHe
を標準状態（以下ガス量は、標準状態で示す）
で、それぞれ10c.c.／minで流しながら、拡散ポン
プおよび油回転ポンプよりなる排気系で、60ｍ
Torrに保持するとともに、13.56MHzの高周波電
力を投入して放電し、Ga・Asウエハーをエツチ
ングした。その際、上記油回転ポンプのケーシン
グに、完全乾燥したN2を10／minで流し、ま
た、油回転ポンプより排出されるガスを、ヤシガ
ラ活性炭をφ50mm、H500mmに充填した吸着塔に
連続導入し、ガス中の有害物を吸着除去した。Example 1 Using a parallel plate type dry etching device, CCl 2 F 2 and He were used as dry etching gas.
under standard conditions (the gas amounts below are shown under standard conditions)
60 m with an exhaust system consisting of a diffusion pump and an oil rotary pump, each flowing at a rate of 10 c.c./min.
The Ga/As wafer was etched by holding it at Torr and discharging it with 13.56MHz high-frequency power. At that time, completely dry N 2 was flowed through the casing of the oil rotary pump at a rate of 10/min, and the gas discharged from the oil rotary pump was continuously introduced into an adsorption tower filled with coconut shell activated carbon to a diameter of 50 mm and a height of 500 mm. , harmful substances in the gas were adsorbed and removed.
その結果、油回転ポンプ出口の酸素量は空気換
算0.1vol％以下であり、また吸着塔出口のGaお
よびAsの塩化物、フツ化物の濃度は９時間連続
運転をした後も、0.01volppm以下であつた。 As a result, the amount of oxygen at the outlet of the oil rotary pump was less than 0.1 vol% in terms of air, and the concentration of Ga and As chlorides and fluorides at the outlet of the adsorption tower was less than 0.01 volppm even after 9 hours of continuous operation. It was hot.
さらに、ドライエツチング開始前、および終了
後油回転ポンプのオイルをサンプリグしてGaお
よびAsの塩化物、フツ化物濃度を測定した結果、
濃度の上昇は認められず、堆積していないことを
示した。 Furthermore, we sampled the oil from the oil rotary pump before and after dry etching and measured the chloride and fluoride concentrations of Ga and As.
No increase in concentration was observed, indicating that no accumulation occurred.
実施例 ２
油回転ポンプの代りにドライ真空ポンプを用
い、吸着塔に、40wt％の水を吸着したシリカゲ
ルをφ50mm、H750mm充填して用いた他は実施例
１と同じにしてGa・Asウエハーのドライエツリ
ングを行なつた。Example 2 A dry vacuum pump was used instead of the oil rotary pump, and the adsorption tower was filled with 50 mm in diameter and 750 mm in height with silica gel adsorbed with 40 wt% water. I did dry etching.
その結果、ドライ真空ポンプ出口の酸素含有量
は、空気に換算して、0.1vol％以下であり、吸着
塔出口におけるGaおよびAsの塩化物、フツ化物
の濃度は10時間にわたつて0.01volppm以下を示
した。 As a result, the oxygen content at the dry vacuum pump outlet was 0.1 vol% or less in terms of air, and the concentration of Ga and As chlorides and fluorides at the adsorption tower outlet was 0.01 volppm or less over 10 hours. showed that.
以上述べたように、本発明の方法は排気系にお
けるGa・Asの塩化物、フツ化物の堆積を防止
し、また、これらを吸着除去して、外気放出させ
ないので、メンテナンス作業、有害物の除去が容
易となるなど、GaおよびAsウエハーのドライエ
ツチングに寄与することが極めて大きい。
As described above, the method of the present invention prevents the accumulation of Ga/As chlorides and fluorides in the exhaust system, and also adsorbs and removes them, preventing them from being released into the outside air. This greatly contributes to dry etching of Ga and As wafers, as it facilitates dry etching.
第１図は本発明におけるドライエツチング排ガ
ス処理方法を実施する装置の一例を示すもので、
第１図は装置のフローを示す図、第２図は堆積防
止機構を示す図である。
１……ドライエツチング室、２……Ga・Asウ
エハー、３……ドライエツチングガス、４……拡
散ポンプ、メカニカルブースタポンプまたはター
ボポンプ、５……油回転ポンプまたはドライ真空
ポンプ（ポンプ）、５ａ……ケーシング、６……
排気系、７……出口ライン、８……吸着剤、９…
…吸着塔、１０……堆積防止機構、１１……乾燥
不活性ガス、１２……パージ導入ライン、１２ａ
……導出ライン。
FIG. 1 shows an example of an apparatus for carrying out the dry etching exhaust gas treatment method according to the present invention.
FIG. 1 is a diagram showing the flow of the apparatus, and FIG. 2 is a diagram showing the deposition prevention mechanism. 1... Dry etching chamber, 2... Ga/As wafer, 3... Dry etching gas, 4... Diffusion pump, mechanical booster pump or turbo pump, 5... Oil rotary pump or dry vacuum pump (pump), 5a ...Casing, 6...
Exhaust system, 7...Outlet line, 8...Adsorbent, 9...
...Adsorption tower, 10...Deposition prevention mechanism, 11...Dry inert gas, 12...Purge introduction line, 12a
...Derivation line.
Claims (1)
ム・ヒ素ウエハーをドライエツチングする際に、
ドライエツチング排ガス中に含まれるガリウムお
よびヒ素の塩化物、フツ化物が真空ポンプ内に堆
積することを防止するため、真空ポンプ内に不活
性ガスを導入する手段と、真空ポンプを加熱する
手段とを有し、かつ上記真空ポンプの排気ガス
を、吸着剤に通して含有する有害物を除去するこ
とを特徴とするガリウム・ヒ素ウエハーのドライ
エツチング排ガスの処理方法。 ２ 吸着剤が水を吸着した吸着剤である特許請求
の範囲第１項記載のガリウム・ヒ素ウエハーのド
ライエツチング排ガスの処理方法。[Claims] 1. When dry etching a gallium arsenide wafer using a gas containing chlorine and fluorine,
In order to prevent chlorides and fluorides of gallium and arsenic contained in the dry etching exhaust gas from accumulating inside the vacuum pump, means for introducing an inert gas into the vacuum pump and means for heating the vacuum pump are provided. 1. A method for treating exhaust gas from dry etching of gallium arsenide wafers, characterized in that the exhaust gas from the vacuum pump is passed through an adsorbent to remove harmful substances contained therein. 2. A method for treating exhaust gas from dry etching of gallium arsenide wafers according to claim 1, wherein the adsorbent is an adsorbent that adsorbs water.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62126701A JPS63291624A (en) | 1987-05-23 | 1987-05-23 | Treatment of exhaust gas in dry etching of gallium-arsenide wafer |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62126701A JPS63291624A (en) | 1987-05-23 | 1987-05-23 | Treatment of exhaust gas in dry etching of gallium-arsenide wafer |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS63291624A JPS63291624A (en) | 1988-11-29 |
| JPH0436727B2 true JPH0436727B2 (en) | 1992-06-17 |
Family
ID=14941707
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP62126701A Granted JPS63291624A (en) | 1987-05-23 | 1987-05-23 | Treatment of exhaust gas in dry etching of gallium-arsenide wafer |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS63291624A (en) |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0715131Y2 (en) * | 1989-01-20 | 1995-04-10 | 古河電気工業株式会社 | Metalorganic vapor phase growth equipment |
| JPH0647233A (en) * | 1992-06-09 | 1994-02-22 | Ebara Infilco Co Ltd | Treatment of exhaust gas containing halogen and halogen compound |
| JP4558176B2 (en) * | 2000-11-17 | 2010-10-06 | 三菱電機株式会社 | Halogen-containing gas processing method and processing apparatus |
| JP2006253517A (en) * | 2005-03-14 | 2006-09-21 | Dainippon Screen Mfg Co Ltd | Vacuum dryer |
| JP2013086088A (en) * | 2011-10-24 | 2013-05-13 | Taiyo Nippon Sanso Corp | Detoxifying method of gas including halide particle |
| KR101514801B1 (en) * | 2013-06-25 | 2015-04-24 | (주)파인텍 | The separation and recycling system for a perfluoro compounds |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS59109227A (en) * | 1982-12-14 | 1984-06-23 | Showa Denko Kk | Treatment of waste gas from dry etching |
| JPS60198394A (en) * | 1984-03-21 | 1985-10-07 | Anelva Corp | Gas discharging device in vacuum disposer |
| JPS6161016U (en) * | 1984-09-27 | 1986-04-24 | ||
| JPH0339198A (en) * | 1989-07-05 | 1991-02-20 | Matsushita Electric Ind Co Ltd | induction heating iron |
-
1987
- 1987-05-23 JP JP62126701A patent/JPS63291624A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS63291624A (en) | 1988-11-29 |
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