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US5043224A Expired / Lapsed US ⏱️ 0.0 years remaining

Chemically enhanced thermal oxidation and nitridation of silicon and products thereof

Assignee: Lehigh University
•
Filing: 1990-04-05
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Granted: 1991-08-27
•
Expires: 2010-04-05
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Abstract

Abstract A process for enhanced thermal oxidation and nitridation of silicon by introduction of fluorine into the oxidation and nitridation ambients.

Inventors

  • 👤 Ralph J. Jaccodine
  • 👤 Paul Schmidt, deceased
  • 👤 executrix Eva Schmidt

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-31 23:08
CPC Classifications
C; C23; C23C; C23C8/00; C23C8/06; C23C8/08; C23C8/10; C23C8/24

Claims Analysis

Total Claims: 36
Claim 1
Independent Claim 91 words
In a process for growing an oxide or nitride surface layer on a silicon substrate by heating said substrate to a temperature adapted to provide optimal growth rates, thicknesses, and electronic qualities of the oxide or nitride film, and exposing said substrate to a reactive gas consisting essentially of oxygen or nitrogen for a period sufficient to form a layer of desired thickness by reaction between said substrate and said gas, the improvement comprising including in said reactive gas less than 0.2 mol % (measured as F) of a fluorine-containing reactant.
Claim 2
Dependent Claim 91 words
In a process for growing an oxide or nitride surface layer on a silicon substrate by heating said substrate to a temperature adapted to provide optimal growth rates, thicknesses, and electronic qualities of the oxide or nitride film, and exposing said substrate to a reactive gas consisting essentially of oxygen or nitrogen for a period sufficient to form a layer of desired thickness by reaction between said substrate and said gas, the improvement comprising including in said reactive gas less than 0.2 mol % (measured as F) of a fluorine-containing reactant.
Claim 3
Dependent Claim 12 words
The process of claim 1 wherein said fluorine-containing reactant is a chloro-fluoro-hydrocarbon.
Claim 4
Dependent Claim 34 words
The process of claim 2 wherein said chloro-fluoro-hydrocarbon is selected from the group of: chlorofluoroethane, dichlorofluoroethane, dichlorodifluoroethane, trichlorofluoroethane, chlorotrifluoroethane, chlorodifluoroethane, Freon 14, Freon 22, Freon 116, Freon 114, and the fluoro of Freon 23.
Claim 5
Dependent Claim 18 words
The process of claim 1 wherein said fluorine-containing reactant is a fluorine-bearing hydrocarbon or freon not containing chlorine.
Claim 6
Dependent Claim 14 words
The process of claim 1 wherein said fluorine-containing reactant contains no chlorine or hydrogen.
Claim 7
Dependent Claim 13 words
The process of claim 5 wherein said fluorine-containing reactant is NF 3 .
Claim 8
Dependent Claim 36 words
The process of claim 5 wherein said oxidizing atmosphere is formed by evaporating said fluorine source into dry gaseous oxygen and mixing the resultant gas with additional dry oxygen gas to achieve a predetermined fluorine concentration.
Claim 9
Dependent Claim 14 words
An oxidized silicon surface material produced in accordance with the process of claim 5.
Claim 10
Dependent Claim 16 words
An oxidized or nitridized silicon surface material produced in accordance with the process of claim 4.
Claim 11
Dependent Claim 114 words
A process for growing an oxide layer on a silicon surface comprising the steps of: a. heating unoxidized silicon to a temperature adapted to provide optimal growth rates, thicknesses, and electronic qualities of the oxide film under an inert atmosphere; b. substituting an oxidizing atmosphere for said inert atmosphere, said oxidizing atmosphere comprising principally oxygen but also comprising up to 0.2 mol % fluorine (measured as F) from a fluorine source comprising NF 3 , fluorine-bearing freons, chlorofluoroethane, dichlorofluoroethane, dichlorodifluoroethane, trichlorofluoroethane, chlorotrifluoroethane, chlorodifluoroethane, Freon 14, Freon 22, Freon 116, Freon 114, and the fluoro form of Freon 23; and c. allowing said oxidizing atmosphere to oxidize said silicon for a predetermined period of time.
Claim 12
Dependent Claim 114 words
A process for growing an oxide layer on a silicon surface comprising the steps of: a. heating unoxidized silicon to a temperature adapted to provide optimal growth rates, thicknesses, and electronic qualities of the oxide film under an inert atmosphere; b. substituting an oxidizing atmosphere for said inert atmosphere, said oxidizing atmosphere comprising principally oxygen but also comprising up to 0.2 mol % fluorine (measured as F) from a fluorine source comprising NF 3 , fluorine-bearing freons, chlorofluoroethane, dichlorofluoroethane, dichlorodifluoroethane, trichlorofluoroethane, chlorotrifluoroethane, chlorodifluoroethane, Freon 14, Freon 22, Freon 116, Freon 114, and the fluoro form of Freon 23; and c. allowing said oxidizing atmosphere to oxidize said silicon for a predetermined period of time.
Claim 13
Dependent Claim 93 words
In a process for growing an oxide or nitride surface layer on a silicon substrate by heating said substrate to a temperature adapted to provide optimal growth rates, thicknesses, and electronic qualities of the oxide or nitride film, and exposing said substrate to a reactive gas consisting essentially of oxygen or nitrogen for a period sufficient to form a layer of desired thickness by reaction between said substrate and said gas, the improvement comprising including in said reactive gas between 0.055 and 0.20 mol % fluorine (measured as F) of a fluorine-containing reactant.
Claim 14
Dependent Claim 93 words
In a process for growing an oxide or nitride surface layer on a silicon substrate by heating said substrate to a temperature adapted to provide optimal growth rates, thicknesses, and electronic qualities of the oxide or nitride film, and exposing said substrate to a reactive gas consisting essentially of oxygen or nitrogen for a period sufficient to form a layer of desired thickness by reaction between said substrate and said gas, the improvement comprising including in said reactive gas between 0.055 and 0.20 mol % fluorine (measured as F) of a fluorine-containing reactant.
Claim 15
Dependent Claim 12 words
The process of claim 11 wherein said fluorine-containing reactant is a chloro-fluoro-hydrocarbon.
Claim 16
Dependent Claim 35 words
The process of claim 12 wherein said chloro-fluoro-hydrocarbon is selected from the group of: chlorofluoroethane, dichlorofluoroethane, dichlorodifluoroethane, trichlorofluoroethane, chlorotrifluoroethane, chlorodifluorethane, Freon 14, Freon 22, Freon 116, Freon 114, and the fluoro form of Freon 23.
Claim 17
Dependent Claim 18 words
The process of claim 11 wherein said fluorine-containing reactant is a fluorine-bearing hydrocarbon or freon not containing chlorine.
Claim 18
Dependent Claim 14 words
The process of claim 11 wherein said fluorine-containing reactant contains no chlorine or hydrogen.
Claim 19
Dependent Claim 13 words
The process of claim 15 wherein said fluorine-containing reactant is NF 3 .
Claim 20
Dependent Claim 36 words
The process of claim 15 wherein said oxidizing atmosphere is formed by evaporating said fluorine source into dried gaseous oxygen and mixing the resultant gas with additional dry oxygen gas to achieve a predetermined fluorine concentration.
Claim 21
Dependent Claim 14 words
An oxidized silicon surface material produced in accordance with the process of claim 15.
Claim 22
Dependent Claim 16 words
An oxidized or nitridized silicon surface material produced in accordance with the process of claim 14.
Claim 23
Dependent Claim 115 words
A process for growing an oxide layer on a silicon surface comprising the steps of: a. heating unoxidized silicon to a temperature adapted to provide optimal growth rates, thicknesses, and electronic qualities of the oxide film under an inert atmosphere; b. substituting an oxidizing atmosphere for said inert atmosphere, said oxidizing atmosphere comprising principally oxygen but also comprising between 0.055 and 0.2 mol % fluorine (measured as F) from a fluorine source comprising NF 3 , fluorine-bearing freons, chlorofluoroethane, dichlorofluoroethane, dichlorodifluoroethane, trichlorofluoroethane, chlorotrifluoroethane, chlorodifluoroethane, Freon 14, Freon 22, Freon 116, Freon 114, and the fluoro from of Freon 23; and c. allowing said oxidizing atmosphere to oxidize said silicon for a predetermined period of time.
Claim 24
Dependent Claim 115 words
A process for growing an oxide layer on a silicon surface comprising the steps of: a. heating unoxidized silicon to a temperature adapted to provide optimal growth rates, thicknesses, and electronic qualities of the oxide film under an inert atmosphere; b. substituting an oxidizing atmosphere for said inert atmosphere, said oxidizing atmosphere comprising principally oxygen but also comprising between 0.055 and 0.2 mol % fluorine (measured as F) from a fluorine source comprising NF 3 , fluorine-bearing freons, chlorofluoroethane, dichlorofluoroethane, dichlorodifluoroethane, trichlorofluoroethane, chlorotrifluoroethane, chlorodifluoroethane, Freon 14, Freon 22, Freon 116, Freon 114, and the fluoro from of Freon 23; and c. allowing said oxidizing atmosphere to oxidize said silicon for a predetermined period of time.
Claim 25
Dependent Claim 93 words
In a process for growing an oxide or nitride surface layer on a silicon substrate by heating said substrate to a temperature adapted to provide optimal growth rates, thicknesses, and electronic qualities of the oxide or nitride film, and exposing said substrate to a reactive gas consisting essentially of oxygen or nitrogen for a period sufficient to form a layer of desired thickness by reaction between said substrate and said gas, the improvement comprising including in said reactive gas between 0.055 and 0.11 mol % fluorine (measured as F) of a fluorine-containing reactant.
Claim 26
Dependent Claim 93 words
In a process for growing an oxide or nitride surface layer on a silicon substrate by heating said substrate to a temperature adapted to provide optimal growth rates, thicknesses, and electronic qualities of the oxide or nitride film, and exposing said substrate to a reactive gas consisting essentially of oxygen or nitrogen for a period sufficient to form a layer of desired thickness by reaction between said substrate and said gas, the improvement comprising including in said reactive gas between 0.055 and 0.11 mol % fluorine (measured as F) of a fluorine-containing reactant.
Claim 27
Dependent Claim 12 words
The process of claim 21 wherein said fluorine-containing reactant is a chloro-fluoro-hydrocarbon.
Claim 28
Dependent Claim 35 words
The process of claim 22 wherein said chloro-fluoro-hydrocarbon is selected from the group of: chlorofluoroethane, dichlorofluoroethane, dichlorodifluoroethane, trichlorofluoroethane, chlorotrifluoroethane, chlorodifluorethane, Freon 14, Freon 22, Freon 116, Freon 114, and the fluoro form of Freon 23.
Claim 29
Dependent Claim 18 words
The process of claim 21 wherein said fluorine-containing reactant is a fluorine-bearing hydrocarbon or freon not containing chlorine.
Claim 30
Dependent Claim 14 words
The process of claim 21 wherein said fluorine-containing reactant contains no chlorine or hydrogen.
Claim 31
Dependent Claim 13 words
The process of claim 25 wherein said fluorine-containing reactant is NF 3 .
Claim 32
Dependent Claim 113 words
A process for growing an oxide layer on a silicon surface comprising the steps of: a. heating unoxidized silicon to a temperature adapted to provide optimal growth rates, thicknesses, and electronic qualities of the oxide film under an inert atmosphere; b. substituting an oxidizing atmosphere for said inert atmosphere, said oxidizing atmosphere comprising principally oxygen but also comprising between 0.055 and 0.11 mol % fluorine (measured as F) from a fluorine source comprising NF 3 , fluorine-bearing freons, chlorofluoroethane, trichlorofluoroethane, chlorotrifluoroethane, chlorodifluoroethane, Freon 14, Freon 22, Freon 116, Freon 114, and the fluoro form of Freon 23; and c. allowing said oxidizing atmosphere to oxidize said silicon for a predetermined period of time.
Claim 33
Dependent Claim 113 words
A process for growing an oxide layer on a silicon surface comprising the steps of: a. heating unoxidized silicon to a temperature adapted to provide optimal growth rates, thicknesses, and electronic qualities of the oxide film under an inert atmosphere; b. substituting an oxidizing atmosphere for said inert atmosphere, said oxidizing atmosphere comprising principally oxygen but also comprising between 0.055 and 0.11 mol % fluorine (measured as F) from a fluorine source comprising NF 3 , fluorine-bearing freons, chlorofluoroethane, trichlorofluoroethane, chlorotrifluoroethane, chlorodifluoroethane, Freon 14, Freon 22, Freon 116, Freon 114, and the fluoro form of Freon 23; and c. allowing said oxidizing atmosphere to oxidize said silicon for a predetermined period of time.
Claim 34
Dependent Claim 36 words
The process of claim 25 wherein said oxidizing atmosphere is formed by evaporating said fluorine source into dried gaseous oxygen and mixing the resultant gas with additional dry oxygen gas to achieve a predetermined fluorine concentration.
Claim 35
Dependent Claim 14 words
An oxidized silicon surface material produced in accordance with the process of claim 25.
Claim 36
Dependent Claim 16 words
An oxidized or nitridized silicon surface material produced in accordance with the process of claim 24.

References Cited (Backward Citations)

US3607480A Cited
US3692571A Cited
US4214919A Cited
US4300989A Cited
US4567061A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1994-08-26 1995-02-25 1995-08-27 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1998-08-26 1999-02-25 1999-08-27 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2002-08-26 2003-02-25 2003-08-27 $7700.00 Window Closed / Lapsed

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