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US5679215A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of in situ cleaning a vacuum plasma processing chamber

Assignee: Lam Research Corp
•
Filing: 1996-01-02
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Granted: 1997-10-21
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Expires: 2016-01-02
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Abstract

Abstract Surfaces having semiconductor oxides, metal oxides and hydrocarbons deposited thereon in a vacuum plasma processing chamber are in situ cleaned by introducing water vapor and SF 6 and/or NF 3 gas in the presence of a plasma discharge. The vapor and gas react to form gaseous HF, and an acidic gas including at least one of H 2 SO 4 and HNO 3 . The discharge ionizes and dissociates the HF and acidic gases to form gaseous reactants for the deposits. The reactants chemically react with the deposits, including the oxides and hydrocarbons, to vaporize these deposits. The vaporized deposits are pumped out of the chamber by the same pump which normally evacuates the chamber to a vacuum. Oxygen and/or H 2 O 2 vapors are introduced in the presence of the plasma to additionally clean the surfaces.

Inventors

  • 👤 Michael S. Barnes
  • 👤 Arthur Kenichi Yasuda

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 03:02
CPC Classifications
H; H01; H01J; H01J37/00; H01J37/32; H01J37/32431; H01J37/32798; H01J37/32853; H01J37/32862; C; C23; C23C; C23C16/00; C23C16/44; C23C16/4401; C23C16/4405; Y; Y10; Y10S; Y10S438/00; Y10S438/905

Claims Analysis

Total Claims: 22
Claim 1
Independent Claim 164 words
A method of in situ cleaning deposits from interior surfaces forming a vacuum plasma processing chamber, the surfaces having at least one of an oxide and hydrocarbon deposited thereon, comprising causing water vapor and at least one of SF 6 and NF 3 gas to be in the chamber in the presence of a plasma discharge while the chamber is in vacuo, the plasma discharge and the vacuum in the chamber being such that (a) the vapor and gas react to form, as gaseous reaction products, (i) HF and (ii) acid including at least one of H 2 SO 4 and HNO 3 , and (b) the vaporous reaction products are ionized and dissociated to form vaporous reactants for the deposits, the vaporous reactants chemically reacting with materials, including at least one of the oxide and the hydrocarbon, in the deposits, so the deposits become vaporized, and pumping the vaporized deposits, including at least one of the oxide and the hydrocarbon, from the chamber.
Claim 2
Independent Claim 164 words
A method of in situ cleaning deposits from interior surfaces forming a vacuum plasma processing chamber, the surfaces having at least one of an oxide and hydrocarbon deposited thereon, comprising causing water vapor and at least one of SF 6 and NF 3 gas to be in the chamber in the presence of a plasma discharge while the chamber is in vacuo, the plasma discharge and the vacuum in the chamber being such that (a) the vapor and gas react to form, as gaseous reaction products, (i) HF and (ii) acid including at least one of H 2 SO 4 and HNO 3 , and (b) the vaporous reaction products are ionized and dissociated to form vaporous reactants for the deposits, the vaporous reactants chemically reacting with materials, including at least one of the oxide and the hydrocarbon, in the deposits, so the deposits become vaporized, and pumping the vaporized deposits, including at least one of the oxide and the hydrocarbon, from the chamber.
Claim 3
Dependent Claim 16 words
The method of claim 1 wherein the SF 6 is supplied without the NF 3 .
Claim 4
Dependent Claim 16 words
The method of claim 1 wherein the NF 3 is supplied without the SF 6 .
Claim 5
Dependent Claim 21 words
The method of claim 1 further including introducing vaporous H 2 O 2 into the chamber simultaneously with the water vapor.
Claim 6
Dependent Claim 46 words
The method of claim 4 wherein there is a partial reaction in the chamber in accordance with at least one of 4H 2 O 2 +SF 6 →H 2 SO 4 +6HF+O 2 , and H 2 O 2 +NF 3 →HNO 3 +HF+O 2 .
Claim 7
Dependent Claim 29 words
The method of claim 1 further including introducing gaseous O 2 into the chamber in the presence of the plasma, the plasma dissociating the introduced gaseous O 2 .
Claim 8
Dependent Claim 19 words
The method of claim 1 wherein the water vapor is introduced into the chamber after the fluorine containing gas.
Claim 9
Dependent Claim 19 words
The method of claim 1 wherein the water vapor is introduced into the chamber before the fluorine containing gas.
Claim 10
Dependent Claim 39 words
The method of claim 1 further including determining whether the chamber is coated with an unacceptable amount of deposits from previous use, and performing the steps of claim 1 if such amount of deposits is determined to be present.
Claim 11
Dependent Claim 29 words
The method of claim 1 wherein the water vapor is produced in a vacuum bubbling chamber having an outlet connected to an inlet of the vacuum plasma processing chamber.
Claim 12
Dependent Claim 27 words
The method of claim 1 wherein the water vapor is derived from an injector having an outlet connected to an inlet of the vacuum plasma processing chamber.
Claim 13
Dependent Claim 38 words
The method of claim 1 wherein there is a partial reaction in the chamber in accordance with at least one of: 4H 2 O+SF 6 →H 2 SO 4 +6HF, and H 2 O+NF 3 →HNO 3 +HF.
Claim 14
Dependent Claim 31 words
The method of claim 1 wherein substantially all of the HF gaseous reaction product is consumed in the reaction with the deposits so virtually no HF is pumped from the chamber.
Claim 15
Independent Claim 76 words
A method of in situ removing deposits from interior surfaces forming a vacuum plasma processing chamber comprising causing water vapor and at least one of NF 3 and SF 6 gas to be in the chamber in vacuo in the presence of a plasma discharge to form vaporous reactants for the deposits, the vaporous reactants reacting with the deposits to form vaporous reaction products, and pumping the vaporous reaction products from the vacuum chamber in vacuo.
Claim 16
Independent Claim 76 words
A method of in situ removing deposits from interior surfaces forming a vacuum plasma processing chamber comprising causing water vapor and at least one of NF 3 and SF 6 gas to be in the chamber in vacuo in the presence of a plasma discharge to form vaporous reactants for the deposits, the vaporous reactants reacting with the deposits to form vaporous reaction products, and pumping the vaporous reaction products from the vacuum chamber in vacuo.
Claim 17
Dependent Claim 16 words
The method of claim 14 wherein the SF 6 is supplied without the NF 3 .
Claim 18
Dependent Claim 16 words
The method of claim 14 wherein the NF 3 is supplied without the SF 6 .
Claim 19
Dependent Claim 21 words
The method of claim 14 further including introducing vaporous H 2 O 2 into the chamber simultaneously with the water vapor.
Claim 20
Dependent Claim 59 words
The method of claim 17 wherein the partial reactions of the H 2 O 2 vapor and the at least one NF 3 and SF 6 are in accordance with at least one of 4H 2 O 2 +SF 6 →H 2 SO 4 +6HF+2O 2 , and H 2 O 2 +NF 3 →HNO 3 +HF+O 2 .
Claim 21
Dependent Claim 48 words
The method of claim 14 wherein the partial reactions of the water vapor and the at least one NF 3 and SF 6 are in accordance with at least one of: 4H 2 O+SF 6 →H 2 SO 4 +6HF, and H 2 O+NF 3 →HNO 3 +HF.
Claim 22
Dependent Claim 41 words
The method of claim 14 wherein HF is one of the formed vaporous reaction products, and substantially all of the HF vaporous reaction product is consumed in the reaction with the deposits so virtually no HF is pumped from the chamber.

References Cited (Backward Citations)

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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2000-10-20 2001-04-21 2001-10-21 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2004-10-20 2005-04-21 2005-10-21 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2008-10-20 2009-04-21 2009-10-21 $7700.00 Window Closed / Lapsed

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