JP2812838B2 - Cleaning method for thin film forming apparatus - Google Patents
Cleaning method for thin film forming apparatusInfo
- Publication number
- JP2812838B2 JP2812838B2 JP18361592A JP18361592A JP2812838B2 JP 2812838 B2 JP2812838 B2 JP 2812838B2 JP 18361592 A JP18361592 A JP 18361592A JP 18361592 A JP18361592 A JP 18361592A JP 2812838 B2 JP2812838 B2 JP 2812838B2
- Authority
- JP
- Japan
- Prior art keywords
- gas
- thin film
- compound
- germanium
- cleaning
- 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
- 238000004140 cleaning Methods 0.000 title claims description 19
- 239000010409 thin film Substances 0.000 title claims description 19
- 238000000034 method Methods 0.000 title claims description 13
- 239000007789 gas Substances 0.000 claims description 35
- 150000001875 compounds Chemical class 0.000 claims description 21
- 239000012298 atmosphere Substances 0.000 claims description 12
- 229910052732 germanium Inorganic materials 0.000 claims description 12
- GNPVGFCGXDBREM-UHFFFAOYSA-N germanium atom Chemical compound [Ge] GNPVGFCGXDBREM-UHFFFAOYSA-N 0.000 claims description 12
- QGZKDVFQNNGYKY-UHFFFAOYSA-O Ammonium Chemical compound [NH4+] QGZKDVFQNNGYKY-UHFFFAOYSA-O 0.000 claims description 7
- 150000002291 germanium compounds Chemical class 0.000 claims description 4
- OAKJQQAXSVQMHS-UHFFFAOYSA-O hydrazinium(1+) Chemical compound [NH3+]N OAKJQQAXSVQMHS-UHFFFAOYSA-O 0.000 claims description 4
- 239000012299 nitrogen atmosphere Substances 0.000 claims description 4
- 238000010438 heat treatment Methods 0.000 claims description 3
- 229910052710 silicon Inorganic materials 0.000 claims description 3
- 239000010703 silicon Substances 0.000 claims description 3
- 150000003377 silicon compounds Chemical class 0.000 claims description 3
- 229910052986 germanium hydride Inorganic materials 0.000 description 4
- 238000004458 analytical method Methods 0.000 description 3
- QUZPNFFHZPRKJD-UHFFFAOYSA-N germane Chemical compound [GeH4] QUZPNFFHZPRKJD-UHFFFAOYSA-N 0.000 description 3
- 239000000843 powder Substances 0.000 description 3
- 239000002994 raw material Substances 0.000 description 3
- BLRPTPMANUNPDV-UHFFFAOYSA-N Silane Chemical compound [SiH4] BLRPTPMANUNPDV-UHFFFAOYSA-N 0.000 description 2
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 2
- 238000005268 plasma chemical vapour deposition Methods 0.000 description 2
- 238000002411 thermogravimetry Methods 0.000 description 2
- 238000002441 X-ray diffraction Methods 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- 229910021417 amorphous silicon Inorganic materials 0.000 description 1
- 239000003085 diluting agent Substances 0.000 description 1
- 239000010408 film Substances 0.000 description 1
- -1 germanium hydride compound Chemical class 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 150000004767 nitrides Chemical class 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 238000005488 sandblasting Methods 0.000 description 1
- 238000007790 scraping Methods 0.000 description 1
- 229910052990 silicon hydride Inorganic materials 0.000 description 1
- 239000002210 silicon-based material Substances 0.000 description 1
- 238000004876 x-ray fluorescence Methods 0.000 description 1
Landscapes
- Chemical Vapour Deposition (AREA)
- Drying Of Semiconductors (AREA)
Description
【０００１】[0001]
【産業上の利用分野】本発明は、薄膜形成装置の内壁、
該装置の治具・部品、配管に堆積したゲルマニウムまた
はゲルマニウム化合物の薄膜、ゲルマニウムを添加した
シリコンまたはシリコン化合物の薄膜をＮ2プラズマ雰
囲気下でクリーニングする際に生成するヘキサフルオロ
ゲルマン酸アンモニウム等を、窒素雰囲気下で加熱また
はＣｌＦ3 ガスあるいはＦ2 ガスと接触させて、装置、
治具、部品、配管を傷つけることなく除去する薄膜形成
装置のクリーニング方法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inner wall of a thin film forming apparatus,
Jigs and parts of the apparatus, a thin film of germanium or a germanium compound deposited on a pipe, a thin film of silicon or a silicon compound to which germanium is added, ammonium hexafluorogermanate generated when cleaning under a N 2 plasma atmosphere, etc. Heating under nitrogen atmosphere or contacting with ClF 3 gas or F 2 gas,
The present invention relates to a method of cleaning a thin film forming apparatus that removes a jig, a component, and a pipe without damaging the jig, a component, and a pipe.
【０００２】[0002]
【従来技術とその解決しようとする課題】モノゲルマン
等を原料としてゲルマニウムまたはゲルマニウム化合物
を成膜する装置、シリコン系化合物薄膜にモノゲルマン
等を原料としてゲルマニウムをドーピングした薄膜を形
成する装置の内部には、水素化ゲルマニウム化合物、そ
の窒素化物等の化合物、水素化シリコンに微量のゲルマ
ニウムを含有した化合物等が付着あるいは堆積する。こ
の様な場合、反応装置内部のパーティクル発生の原因と
なるため、随時クリーニングしなければならない。2. Description of the Related Art An apparatus for forming germanium or a germanium compound from monogermane or the like as a raw material, and an apparatus for forming a germanium-doped thin film on a silicon-based compound thin film from monogermane or the like as a raw material. In this method, a compound such as a germanium hydride compound or a nitride thereof, a compound containing a small amount of germanium in silicon hydride, or the like is attached or deposited. In such a case, it is necessary to clean the reaction apparatus at any time because it causes particles to be generated inside the reaction apparatus.
【０００３】そのため、現在、この様な化合物の付着
物、堆積物は、人力による掻き出し、拭き取り、サンド
ブラスト、酸アルカリによる湿式洗浄等の方法で除去さ
れている。また、この様な化合物を大気中に放出すると
発火等の危険性も伴う。したがって、反応装置を開放す
ることなく、安全かつ簡便なクリーニング法が望まれて
いる。Therefore, at present, such deposits and deposits of the compounds are removed by methods such as manual scraping, wiping, sand blasting, and wet cleaning with an acid alkali. Further, when such a compound is released into the atmosphere, there is a risk of ignition or the like. Therefore, there is a demand for a safe and simple cleaning method without opening the reactor.
【０００４】また、特開平１−３０７２２９号には、Ｃ
ｌＦ3 ガスを用いたクリーニング方法が開示され、さら
に特開平２−７７５７９号には、プラズマＣＶＤ装置に
おいて、ＣｌＦ3 ガスを用いたプラズマレスおよびプラ
ズマによるクリーニング方法が開示されている。しか
し、プラズマクリーニングで実施した場合、白色付着物
が生成するため、これを除去する必要がある。Japanese Patent Application Laid-Open No. 1-307229 discloses that C
A cleaning method using 1F 3 gas is disclosed, and Japanese Patent Application Laid-Open No. 2-77579 discloses a plasma-less and plasma-less cleaning method using ClF 3 gas in a plasma CVD apparatus. However, when the cleaning is performed by plasma cleaning, white deposits are generated, and it is necessary to remove the deposits.
【０００５】[0005]
【課題を解決するための手段】本発明者らはかかる問題
点に鑑み、鋭意検討した結果、特定の温度での加熱また
は特定の温度のＣｌＦ3 ガスあるいはＦ2 ガスを使用し
て、当該化合物と接触反応させる際に生成する白色付着
物を除去することにより装置を開放することなく容易に
堆積物を除去できることを見出した。Means for Solving the Problems In view of the above problems, the present inventors have conducted intensive studies and as a result, have been able to heat the compound at a specific temperature or use ClF 3 gas or F 2 gas at a specific temperature to obtain the compound. It has been found that deposits can be easily removed without opening the apparatus by removing white deposits generated when the contact reaction is made.
【０００６】すなわち本発明は、ゲルマニウムを添加し
たシリコンまたはシリコン化合物の薄膜およびゲルマニ
ウムまたはゲルマニウム化合物の薄膜を製造する装置内
壁、該装置の治具・部品、配管に堆積した該化合物をＮ
2中のプラズマ雰囲気で除去する際に生成するヘキサフ
ルオロゲルマン酸アンモニウムおよびヘキサフルオロゲ
ルマニウム酸ヒドラジニウムを、反応装置内部を窒素雰
囲気下で２２０℃以上に加熱するか、１００℃以上の温
度でＣｌＦ3 ガスあるいはＦ2 ガスと反応させ除去する
ことを特徴とする薄膜形成装置のクリーニング方法を提
供するものである。That is, the present invention relates to a method for producing a thin film of silicon or a silicon compound to which germanium is added and an inner wall of an apparatus for producing a thin film of germanium or a germanium compound, a jig / part of the apparatus, and the compound deposited on a pipe.
Ammonium hexafluorogermanate and hydrazinium hexafluorogermanate generated during removal in the plasma atmosphere in 2 are heated to 220 ° C. or more under a nitrogen atmosphere in the reactor or ClF 3 gas at a temperature of 100 ° C. or more. Another object of the present invention is to provide a method for cleaning a thin film forming apparatus, wherein the cleaning method is characterized by reacting with a F 2 gas and removing the same.
【０００７】本発明において、クリーニングする方法と
しては、ＣｌＦ3 ガスあるいはＦ2ガスと、プラズマ雰
囲気中で反応させた後、該ガス等と１００℃以上で反応
させるもので、具体的には、プラズマ雰囲気中で除去す
る場合には、希釈ガスとしてＮ2 ガスを使用するとＣｌ
Ｆ3 ガスあるいはＦ2 ガスと装置内部に付着、堆積した
ゲルマニウムを含有した化合物との反応によりヘキサフ
ルオロゲルマン酸アンモニウム、ヘキサフルオロゲルマ
ニウム酸ヒドラジニウム等の生成が起こる。そのため、
ヘキサフルオロゲルマン酸アンモニウム等が生成した場
合には、反応装置内部を２２０℃以上に加熱するか、Ｃ
ｌＦ3 ガスあるいはＦ2 ガス雰囲気下で１００℃以上の
温度で加熱することによりこれら化合物を簡単に除去で
きる。In the present invention, a cleaning method is to react with a ClF 3 gas or F 2 gas in a plasma atmosphere and then react with the gas or the like at 100 ° C. or more. When removing in an atmosphere, if N 2 gas is used as a diluent gas,
The reaction between the F 3 gas or the F 2 gas and the germanium-containing compound deposited and deposited inside the apparatus generates ammonium hexafluorogermanate, hydrazinium hexafluorogermanate, and the like. for that reason,
When ammonium hexafluorogermanate or the like is generated, heat the inside of the reactor to 220 ° C. or higher,
These compounds can be easily removed by heating at a temperature of 100 ° C. or more in an atmosphere of IF 3 gas or F 2 gas.
【０００８】上述したような方法により、比較的簡単に
薄膜形成装置内壁、該装置の治具・部品、配管等の付着
物、堆積物をクリーニング処理できる。According to the above-described method, it is possible to relatively easily clean deposits and deposits on the inner wall of the thin film forming apparatus, jigs and parts of the apparatus, piping, and the like.
【０００９】[0009]
【実施例】以下、本発明を実施例により具体的に説明す
るが、本発明はかかる実施例により限定されるものでは
ない。EXAMPLES Hereinafter, the present invention will be described specifically with reference to examples, but the present invention is not limited to these examples.
【００１０】比較例 プラズマＣＶＤにより、モノシラン、モノゲルマンを原
料ガスとしてアモルファスシリコン膜にゲルマニウムを
微量添加した薄膜を形成した。その際反応器壁には、薄
膜が付着すると同時に粉体が生成した。この装置内部に
プラズマ雰囲気中でＮ2 で希釈した１ｖｏｌ％ＣｌＦ3
ガスを圧力２ｔｏｒｒで導入し、装置内部のクリーニン
グを試みた。ＣｌＦ3 ガス導入後に反応器内部を観察し
たところ、白色の化合物が付着していた。同様にＮ2 で
希釈した１ｖｏｌ％Ｆ2 ガスを圧力２ｔｏｒｒで導入し
クリーニングを試みたところ、同じく白色の化合物が付
着していた。Comparative Example A thin film was formed by plasma CVD using monosilane and monogermane as raw material gases and adding a small amount of germanium to an amorphous silicon film. At this time, a powder was formed on the reactor wall at the same time as the thin film was attached. 1 vol% ClF 3 diluted with N 2 in a plasma atmosphere inside the apparatus
Gas was introduced at a pressure of 2 torr, and an attempt was made to clean the inside of the apparatus. When the inside of the reactor was observed after the introduction of the ClF 3 gas, a white compound was found to adhere. Similarly, when cleaning was attempted by introducing 1 vol% F 2 gas diluted with N 2 at a pressure of 2 torr, a white compound was also adhered.
【００１１】この白色の化合物をＸ線回折法、蛍光Ｘ線
分析法にて分析したところ、ヘキサフルオロゲルマニウ
ム酸ヒドラジニウム等を含有するヘキサフルオロゲルマ
ン酸アンモニウムを主成分とする化合物であった。When this white compound was analyzed by X-ray diffraction and X-ray fluorescence analysis, it was found to be a compound mainly composed of ammonium hexafluorogermanate containing hydrazinium hexafluorogermanate and the like.
【００１２】実験例 この粉末（４０ｍｇ）を熱重量分析で１００ｖｏｌ％Ｃ
ｌＦ3 ガス雰囲気中で分析したところ、１００℃付近か
ら急激に反応を開始し気化した（図１）。同様の分析を
１００ｖｏｌ％Ｆ2 ガス雰囲気中にて実施しが、ＣｌＦ
3 ガスの場合と同じ結果が得られた。また、窒素雰囲気
下でこの粉末を常温から徐々に加熱したところ２２０℃
から重量減少が確認された。Experimental Example The powder (40 mg) was analyzed by thermogravimetric analysis at 100 vol% C.
As a result of analysis in an IF 3 gas atmosphere, the reaction started rapidly around 100 ° C. and vaporized (FIG. 1). The same analysis was performed in a 100 vol% F 2 gas atmosphere,
The same result as in the case of three gases was obtained. When the powder was gradually heated from room temperature under a nitrogen atmosphere,
From the results, a decrease in weight was confirmed.
【００１３】実施例１ 比較例と同様の条件で薄膜の形成を行い、クリーニング
を行った。反応器内部に白色の化合物が付着していた。
反応器内部に１５０℃の１０ｖｏｌ％ＣｌＦ3ガスを圧
力２ｔｏｒｒで導入した。その結果、生成した白色の化
合物は完全に除去できた。また、ＣｌＦ3 ガスをＦ2 ガ
スに代えて同条件で除去を行ったところ、白色の化合物
は、完全に除去できた。Example 1 A thin film was formed under the same conditions as in the comparative example, and cleaning was performed. A white compound adhered inside the reactor.
10 vol% ClF 3 gas at 150 ° C. was introduced into the reactor at a pressure of 2 torr. As a result, the generated white compound could be completely removed. Further, when the ClF 3 gas was replaced with the F 2 gas and the removal was performed under the same conditions, the white compound was completely removed.
【００１４】実施例２ 実施例１と同様の条件で薄膜の形成を行い、付着した部
分の温度１１０℃に保持し、プラズマ雰囲気したＮ2で
希釈した１ｖｏｌ％ＣｌＦ3 ガスを圧力２ｔｏｒｒの条
件で導入しクリーニングを行った。その結果、白色の化
合物は生成せず完全にクリーニングできた。また、Ｃｌ
Ｆ3 ガスをＦ2 ガスに代えて同条件でクリーニングを行
ったところ、白色の化合物は生成せず完全にクリーニン
グできた。Example 2 A thin film was formed under the same conditions as in Example 1 and the temperature of the adhered portion was maintained at 110 ° C., and a 1 vol% ClF 3 gas diluted with N 2 in a plasma atmosphere was applied under a pressure of 2 torr. Introduced and cleaned. As a result, a white compound was not generated and cleaning was completed. Also, Cl
When the F 3 gas was cleaned under the same conditions in place of the F 2 gas, a white compound could be completely cleaned without generating.
【００１５】[0015]
【発明の効果】ＣｌＦ3 ガス、Ｆ2 ガスを用いる本発明
のプラズマ雰囲気下におけるクリーニング方法は、薄膜
形成装置、治具、部品、配管等に付着、堆積したゲルマ
ニウム、ゲルマニウム含有化合物を装置の開放を行うこ
となく、安全かつ効率的に除去クリーニングを可能にす
るものである。According to the cleaning method of the present invention using a ClF 3 gas and a F 2 gas in a plasma atmosphere, the germanium and the germanium-containing compound deposited and deposited on a thin film forming apparatus, a jig, a part, a pipe and the like are opened. The cleaning can be performed safely and efficiently without performing the cleaning.
【図１】実験例の白色化合物（ヘキサフルオロゲルマン
酸アンモニウム）の熱重量分析の結果を示す。FIG. 1 shows the results of thermogravimetric analysis of a white compound (ammonium hexafluorogermanate) of an experimental example.
───────────────────────────────────────────────────── フロントページの続き (56)参考文献 特開 昭64−17857（ＪＰ，Ａ) 特開 平２−77579（ＪＰ，Ａ) 特開 平３−219080（ＪＰ，Ａ) 特開 平３−127830（ＪＰ，Ａ) (58)調査した分野(Int.Cl.6，ＤＢ名) C09K 13/08 C23C 16/44 H01L 21/302 ＣＡ（ＳＴＮ)──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-64-17857 (JP, A) JP-A-2-77579 (JP, A) JP-A-3-219080 (JP, A) JP-A-3- 127830 (JP, A) (58) Fields investigated (Int. Cl. 6 , DB name) C09K 13/08 C23C 16/44 H01L 21/302 CA (STN)
Claims (1)
シリコン化合物の薄膜およびゲルマニウムまたはゲルマ
ニウム化合物の薄膜を製造する装置内壁、該装置の治具
・部品、配管に堆積した該化合物をＮ2中のプラズマ雰
囲気で除去する際に生成するヘキサフルオロゲルマン酸
アンモニウムおよびヘキサフルオロゲルマニウム酸ヒド
ラジニウムを、反応装置内部を窒素雰囲気下で２２０℃
以上に加熱するか、１００℃以上の温度でＣｌＦ3 ガス
あるいはＦ2 ガスと反応させ除去することを特徴とする
薄膜形成装置のクリーニング方法。An apparatus for producing a thin film of silicon or a silicon compound to which germanium is added and a thin film of germanium or a germanium compound, the compound deposited on an inner wall of a device, a jig / part of the device, and a pipe are exposed to a plasma atmosphere in N 2. Ammonium hexafluorogermanate and hydrazinium hexafluorogermanate, which are generated during the removal, are heated to 220 ° C. in a nitrogen atmosphere in a reactor.
A method for cleaning a thin film forming apparatus, comprising heating the above or reacting with a ClF 3 gas or a F 2 gas at a temperature of 100 ° C. or more to remove the gas.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP18361592A JP2812838B2 (en) | 1992-07-10 | 1992-07-10 | Cleaning method for thin film forming apparatus |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP18361592A JP2812838B2 (en) | 1992-07-10 | 1992-07-10 | Cleaning method for thin film forming apparatus |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0625662A JPH0625662A (en) | 1994-02-01 |
| JP2812838B2 true JP2812838B2 (en) | 1998-10-22 |
Family
ID=16138887
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP18361592A Expired - Lifetime JP2812838B2 (en) | 1992-07-10 | 1992-07-10 | Cleaning method for thin film forming apparatus |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2812838B2 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20030010354A1 (en) * | 2000-03-27 | 2003-01-16 | Applied Materials, Inc. | Fluorine process for cleaning semiconductor process chamber |
| DE102005047081B4 (en) * | 2005-09-30 | 2019-01-31 | Robert Bosch Gmbh | Process for the plasma-free etching of silicon with the etching gas ClF3 or XeF2 |
-
1992
- 1992-07-10 JP JP18361592A patent/JP2812838B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0625662A (en) | 1994-02-01 |
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