Patent US5294568A successfully refreshed from Google Patents.
US5294568A
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Method of selective etching native oxide
Assignee: Aixtron Inc
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Filing: 1992-04-10
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Granted: 1994-03-15
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Expires: 2012-04-10
Abstract
Abstract A method of selective etching of native oxide on a substrate is disclosed in which hydrogen halide vapor and water vapor are exposed to the substrate surface under appropriate conditions and long enough to remove native oxide but not long enough to remove any significant amount of other oxides. Treating conditions are maintained to prevent water vapor from condensing on the substrate until sufficient native oxide is etched so that substantially all the native oxide will be etched before appreciable other oxides are etched.
Inventors
- 👤 Michael A. McNeilly
- 👤 Bruce E. Deal
- 👤 Dah-Bin Kao
- 👤 John de Larios
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 19:52
CPC Classifications
H; H10; H10P; H10P70/00; H10P70/10; H10P70/12; C; C04; C04B; C04B41/00; C04B41/53; C04B41/5338; C04B41/5346; H10P50/00; H10P50/20; H10P50/28; H10P50/282; H10P50/283; H10P72/00; H10P72/04; H10P72/0402; H10P72/0418; H10P72/0421; Y; Y10; Y10S; Y10S148/00; Y10S148/017; Y10S148/051; Y10S438/00; Y10S438/906; Y10S438/974
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
68 words
The method for processing semiconductor wafers comprising the steps of: positioning a substrate in a treatment chamber; exposing the substrate to a mixture of hydrogen halide vapor and water vapor to etch native oxide from a surface of the substrate; and controlling the partial pressure of at least one of the vapors to delay condensation of water vapor on other oxide surface while native oxides are being etched.
Claim 2
Independent Claim
68 words
The method for processing semiconductor wafers comprising the steps of: positioning a substrate in a treatment chamber; exposing the substrate to a mixture of hydrogen halide vapor and water vapor to etch native oxide from a surface of the substrate; and controlling the partial pressure of at least one of the vapors to delay condensation of water vapor on other oxide surface while native oxides are being etched.
Claim 3
Dependent Claim
23 words
In the method of claim 1 said exposing step comprising exposing the substrate to at least 0.1 wt. percent hydrogen halide in water.
Claim 4
Dependent Claim
24 words
In the method of claim 2 said exposing step comprising exposing the substrate to no more than 49 weight percent hydrogen halide in water.
Claim 5
Dependent Claim
21 words
In the method of claim 1 forming the hydrogen halide vapor and water vapor from hydrogen halide in an aqueous solution.
Claim 6
Dependent Claim
17 words
In the method of claim 4 forming the hydrogen halide from hydrogen fluoride in an aqueous solution.
Claim 7
Dependent Claim
24 words
In the method of claim 4 forming the hydrogen halide from hydrogen fluoride in an aqueous solution and hydrogen chloride in an aqueous solution.
Claim 8
Dependent Claim
20 words
In the method of claim 4 forming the hydrogen halide from hydrogen fluoride and hydrogen chloride in an aqueous solution.
Claim 9
Independent Claim
85 words
The method for processing semiconductor wafers comprising the steps of: positioning a substrate in a treatment chamber; controlling the temperature of the substrate; exposing the substrate to a mixture of hydrogen halide vapor and either water vapor or a vapor of a hydroxyl-containing replacement for water vapor to etch native oxides from a surface of the substrate; and controlling the partial pressure of at least one of the vapors to delay condensation of water vapor on the other oxides while native oxides are being etched.
Claim 10
Independent Claim
85 words
The method for processing semiconductor wafers comprising the steps of: positioning a substrate in a treatment chamber; controlling the temperature of the substrate; exposing the substrate to a mixture of hydrogen halide vapor and either water vapor or a vapor of a hydroxyl-containing replacement for water vapor to etch native oxides from a surface of the substrate; and controlling the partial pressure of at least one of the vapors to delay condensation of water vapor on the other oxides while native oxides are being etched.
Claim 11
Dependent Claim
27 words
In the method of claim 8 said exposing step comprising exposing the substrate to at least 0.1 wt. percent hydrogen halide or hydroxyl containing replacement in water.
Claim 12
Dependent Claim
28 words
In the method of claim 9 said exposing step comprising exposing the substrate to no more than 49 wt. percent hydrogen halide or hydroxyl containing replacement in water.
Claim 13
Dependent Claim
21 words
In the method of claim 8 forming the hydrogen halide vapor and water vapor from hydrogen halide in an aqueous solution.
Claim 14
Dependent Claim
18 words
In the method of claim 11 forming the hydrogen halide vapor from hydrogen fluoride in an aqueous solution.
Claim 15
Dependent Claim
24 words
In the method of claim 11 forming the hydrogen halide from hydrogen fluoride in an aqueous solution and hydrogen chloride in an aqueous solution.
Claim 16
Dependent Claim
20 words
In the method of claim 11 forming the hydrogen halide from hydrogen fluoride and hydrogen chloride in an aqueous solution.
Claim 17
Independent Claim
90 words
The method for processing semiconductor wafers comprising the steps of: positioning a semiconductor wafer in a treatment chamber; controlling the temperature of the wafer; vaporizing an aqueous solution containing an hydrogen halide; mixing a carrier gas with said vaporized aqueous solution producing a mixture of said vaporized aqueous solution and said carrier gas; exposing a surface of said wafer to said mixture; and controlling the partial pressures of at least one of the vapors to delay condensation of water vapor on other oxides surface while native oxides are being etched.
Claim 18
Independent Claim
90 words
The method for processing semiconductor wafers comprising the steps of: positioning a semiconductor wafer in a treatment chamber; controlling the temperature of the wafer; vaporizing an aqueous solution containing an hydrogen halide; mixing a carrier gas with said vaporized aqueous solution producing a mixture of said vaporized aqueous solution and said carrier gas; exposing a surface of said wafer to said mixture; and controlling the partial pressures of at least one of the vapors to delay condensation of water vapor on other oxides surface while native oxides are being etched.
Claim 19
Dependent Claim
17 words
In the method of claim 15 forming the hydrogen halide from hydrogen fluoride in an aqueous solution.
Claim 20
Dependent Claim
24 words
In the method of claim 15 forming the hydrogen halide from hydrogen fluoride in an aqueous solution and hydrogen chloride in an aqueous solution.
References Cited (Backward Citations)
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