US5152819A
Expired / Lapsed
US
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Method of making fused silica
Assignee: Corning Inc
•
Filing: 1991-08-26
•
Granted: 1992-10-06
•
Expires: 2011-08-26
Abstract
Abstract This invention relates to the production of high purity fused silica glass through oxidation and/or flame hydrolysis of a halide-free, organosilicon-R compound in vapor form having the following properties: (a) producing a gas stream of a halide-free silicon-containing compound in vapor form capable of being converted through thermal decomposition with oxidation or flame hydrolysis to SiO 2 ; (b) passing said gas stream into the flame of a combustion burner to form amorphous particles of fused SiO 2 ; (c) depositing said amorphous particles onto a support; and (d) either essentially simultaneously with said deposition or subsequently thereto consolidating said deposit of amorphous particles into a virtually nonporous body; the improvement comprising utilizing a halide-free, organosilicon-R compound in vapor form having the following properties: (1) a Si--R bond dissociation energy that is no higher than the dissociation energy of the Si--O bond; (2) a boiling point no higher than 350° C.; and (3) which, upon pyrolysis and/or hydrolysis, will produce decomposition products beside SiO 2 which are deemed to be environmentally safe or the emissions are below acceptable governmental standards.
Inventors
- 👤 Jeffery L. Blackwell
- 👤 Michael S. Dobbins
- 👤 Robert E. McLay
- 👤 Carlton M. Truesdale
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 16:51
CPC Classifications
C; C03; C03B; C03B37/00; C03B37/01; C03B37/012; C03B37/014; C03B37/01413; C03B19/00; C03B19/14; C03B19/1415; C03B37/01446; C03C; C03C3/00; C03C3/04; C03C3/06; C03B2201/00; C03B2201/02; C03B2201/06; C03B2201/08; C03B2201/10; C03B2201/20; C03B2201/28; C03B2201/30; C03B2201/31; C03B2201/32; C03B2201/34; C03B2201/40; C03B2201/42; C03B2201/50; C03B2201/54; C03B2207/00; C03B2207/04; C03B2207/06; C03B2207/30; C03B2207/32; C03B2207/50; C03B2207/52; C03B2207/80; C03B2207/85; C03C2201/00; C03C2201/02; C03C2201/06; C03C2201/20; C03C2201/28; C03C2203/00; C03C2203/40; Y; Y10; Y10S; Y10S65/00; Y10S65/90; Y10S65/901
Claims Analysis
Total Claims: 39
Claim 1
Independent Claim
190 words
In a method for making a virtually non-porous body of high purity fused silica glass which comprises the steps of: (a) producing a gas stream of a halide-free, silicon-containing compound in vapor form capable of being converted through thermal decomposition with oxidation or flame hydrolysis to SiO 2 ; (b) passing said gas stream into the flame of a combustion burner to form amorphous particles of high purity fused silica; (c) depositing said amorphous particles onto a support; and (d) either essentially simultaneously with said deposition or subsequently thereto consolidating said deposit of amorphous particles into a virtually non-porous body of high purity fused silica; the improvement comprising utilizing as the halide-free, silicon-containing compound an organosilicon-R compound in vapor form selected from the group consisting of organosilicon-nitrogen compounds having a basic Si--N--Si structure, siloxasilazanes having a basic Si--N--Si--O--Si structure, and mixtures thereof having the following properties; (1) a Si--R bond dissociation energy that is no higher than the dissociation energy of the Si--O bond; (2) a boiling point no higher than 350° C., and (3) which, upon pyrolysis and/or hydrolysis, will produce decomposition products beside SiO 2 which are non-toxic.
Claim 2
Dependent Claim
190 words
In a method for making a virtually non-porous body of high purity fused silica glass which comprises the steps of: (a) producing a gas stream of a halide-free, silicon-containing compound in vapor form capable of being converted through thermal decomposition with oxidation or flame hydrolysis to SiO 2 ; (b) passing said gas stream into the flame of a combustion burner to form amorphous particles of high purity fused silica; (c) depositing said amorphous particles onto a support; and (d) either essentially simultaneously with said deposition or subsequently thereto consolidating said deposit of amorphous particles into a virtually non-porous body of high purity fused silica; the improvement comprising utilizing as the halide-free, silicon-containing compound an organosilicon-R compound in vapor form selected from the group consisting of organosilicon-nitrogen compounds having a basic Si--N--Si structure, siloxasilazanes having a basic Si--N--Si--O--Si structure, and mixtures thereof having the following properties; (1) a Si--R bond dissociation energy that is no higher than the dissociation energy of the Si--O bond; (2) a boiling point no higher than 350° C., and (3) which, upon pyrolysis and/or hydrolysis, will produce decomposition products beside SiO 2 which are non-toxic.
Claim 3
Dependent Claim
25 words
A method according to claim 1 wherein said organosilicon-nitrogen compound is selected from the group consisting of an aminosilane, a linear silazane, and a cyclosilazane.
Claim 4
Dependent Claim
22 words
A method according to claim 2 wherein said aminosilane is tris ketenimine, said linear silazane is nonamethyltrisilazane and said cyclosilazane is octamethylcyclotetrasilazane.
Claim 5
Dependent Claim
11 words
A method according to claim 1 wherein said siloxasilazane is hexamethylcyclotrisiloxazane.
Claim 6
Dependent Claim
16 words
A method according to claim 1 wherein said gas stream is comprised of an inert gas.
Claim 7
Dependent Claim
12 words
A method according to claim 5 wherein said inert gas is nitrogen.
Claim 8
Dependent Claim
260 words
In a method for making a virtually non-porous body of high purity, fused silica glass doped with at least one dopant oxide comprising the steps of: (a) producing a gas stream containing a halide-free silicon-containing compound in vapor form capable of being converted through thermal decomposition with oxidation or flame hydrolysis to SiO 2 and a compound in vapor form capable of being converted through oxidation or flame hydrolysis to at least one member of the group consisting of P 2 O 5 and a metal oxide which has a metallic component selected from the Groups IA, IB, IIA, IIB, IIIA, IIIB, IVA, IVB, VA, and the rare earth series of the Periodic Table; (b) passing said gas stream into the flame of a combustion burner to form amorphous particles of high purity fused SiO 2 doped with an oxide dopant; (c) depositing said amorphous particles onto a support; and (d) either essentially simultaneously with said deposition or subsequently thereto consolidating said deposit of amorphous particles into a virtually non-porous body of high purity fused silica; the improvement comprising utilizing as the halide-free, silicon-containing compound an organosilicon-R compound in vapor form selected from the group consisting of organosilicon-nitrogen compounds having a Si--N--Si structure, siloxasilazanes having a basic Si--N--Si--O--Si structure, and mixtures thereof having the following properties; (1) a Si--R bond dissociation energy that is no higher than the dissociation energy of the Si--O bond; (2) a boiling point no higher than 350° C., and (3) which, upon pyrolysis and/or hydrolysis, will produce decomposition products beside SiO 2 which are non-toxic.
Claim 9
Dependent Claim
260 words
In a method for making a virtually non-porous body of high purity, fused silica glass doped with at least one dopant oxide comprising the steps of: (a) producing a gas stream containing a halide-free silicon-containing compound in vapor form capable of being converted through thermal decomposition with oxidation or flame hydrolysis to SiO 2 and a compound in vapor form capable of being converted through oxidation or flame hydrolysis to at least one member of the group consisting of P 2 O 5 and a metal oxide which has a metallic component selected from the Groups IA, IB, IIA, IIB, IIIA, IIIB, IVA, IVB, VA, and the rare earth series of the Periodic Table; (b) passing said gas stream into the flame of a combustion burner to form amorphous particles of high purity fused SiO 2 doped with an oxide dopant; (c) depositing said amorphous particles onto a support; and (d) either essentially simultaneously with said deposition or subsequently thereto consolidating said deposit of amorphous particles into a virtually non-porous body of high purity fused silica; the improvement comprising utilizing as the halide-free, silicon-containing compound an organosilicon-R compound in vapor form selected from the group consisting of organosilicon-nitrogen compounds having a Si--N--Si structure, siloxasilazanes having a basic Si--N--Si--O--Si structure, and mixtures thereof having the following properties; (1) a Si--R bond dissociation energy that is no higher than the dissociation energy of the Si--O bond; (2) a boiling point no higher than 350° C., and (3) which, upon pyrolysis and/or hydrolysis, will produce decomposition products beside SiO 2 which are non-toxic.
Claim 10
Dependent Claim
24 words
A method according to claim 7 wherein said organosilicon-nitrogen compound is selected from the group consisting of an aminosilane, a silazane, and a cyclosilazane.
Claim 11
Dependent Claim
22 words
A method according to claim 8 wherein said aminosilane is tris ketenimine, said linear silazane is nonamethyltrisilazane and said cyclosilazane is octamethylcyclotetrasilazane.
Claim 12
Dependent Claim
11 words
A method according to claim 7 wherein said siloxasilazane is hexamethylcyclotrisiloxazane.
Claim 13
Dependent Claim
16 words
A method according to claim 7 wherein said gas stream is comprised of an inert gas.
Claim 14
Dependent Claim
65 words
A method according to claim 7 wherein said compound in vapor form capable of being converted to at least one member of the group consisting of P 2 O 5 and a metal oxide which has a metallic component selected from the Groups IA, IB, IIA, IIB, IIIA, IIIB, IVA, IVB, VA, and the rare earth series of the Periodic Table is a halide-containing compound.
Claim 15
Dependent Claim
12 words
A method according to claim 12 wherein said inert gas is nitrogen.
Claim 16
Dependent Claim
65 words
A method according to claim 7 wherein said compound in vapor form capable of being converted to at least one member of the group consisting of P 2 O 5 and a metal oxide which has a metallic component selected from the Groups IA, IB, IIA, IIB, IIIA, IIIB, IVA, IVB, VA, and the rare earth series of the Periodic Table is a halide-containing compound.
Claim 17
Dependent Claim
196 words
In a method for making optical waveguide fibers of high purity fused silica glass through the outside vapor deposition process comprising the steps of: (a) producing a gas stream containing a halide-free silicon-containing compound in vapor form capable of being converted through thermal decomposition with oxidation or flame hydrolysis to SiO 2 ; (b) passing said gas stream into the flame of a combustion burner to form amorphous particles of high purity fused SiO 2 ; (c) depositing said amorphous particles onto a mandrel; (d) consolidating said deposit of amorphous particles into a non-porous, transparent glass body of high purity fused silica; and (e) drawing optical waveguide fiber from said body; the improvement comprising utilizing as the halide-free silicon-containing compound an organosilicon-R compound in vapor form selected from the group consisting of organosilicon-nitrogen compounds having a basic Si--N--Si structure, siloxasilazanes having a basic Si--N--Si--O--Si structure, and mixtures thereof having the following properties; (1) a Si--R bond dissociation energy that is no higher than the dissociation energy of the Si--O bond; (2) a boiling point no higher than 350° C.; and (3) which, upon pyrolysis and/or hydrolysis, will produce decomposition products beside SiO 2 which are non-toxic.
Claim 18
Dependent Claim
196 words
In a method for making optical waveguide fibers of high purity fused silica glass through the outside vapor deposition process comprising the steps of: (a) producing a gas stream containing a halide-free silicon-containing compound in vapor form capable of being converted through thermal decomposition with oxidation or flame hydrolysis to SiO 2 ; (b) passing said gas stream into the flame of a combustion burner to form amorphous particles of high purity fused SiO 2 ; (c) depositing said amorphous particles onto a mandrel; (d) consolidating said deposit of amorphous particles into a non-porous, transparent glass body of high purity fused silica; and (e) drawing optical waveguide fiber from said body; the improvement comprising utilizing as the halide-free silicon-containing compound an organosilicon-R compound in vapor form selected from the group consisting of organosilicon-nitrogen compounds having a basic Si--N--Si structure, siloxasilazanes having a basic Si--N--Si--O--Si structure, and mixtures thereof having the following properties; (1) a Si--R bond dissociation energy that is no higher than the dissociation energy of the Si--O bond; (2) a boiling point no higher than 350° C.; and (3) which, upon pyrolysis and/or hydrolysis, will produce decomposition products beside SiO 2 which are non-toxic.
Claim 19
Dependent Claim
24 words
A method according to claim 15 wherein said organosilicon-nitrogen compound is selected from the group consisting of an aminosilane, a silazane, and a cyclosilazane.
Claim 20
Dependent Claim
22 words
A method according to claim 16 wherein said aminosilane is tris ketenimine, said linear silazane is nonamethyltrisilazane and said cyclosilazane is octamethylcyclotetrasilazane.
Claim 21
Dependent Claim
11 words
A method according to claim 15 wherein said siloxasilazane is hexamethylcyclotrisiloxazane.
Claim 22
Dependent Claim
16 words
A method according to claim 15 wherein said gas stream is comprised of an inert gas.
Claim 23
Dependent Claim
12 words
A method according to claim 19 wherein said inert gas is nitrogen.
Claim 24
Dependent Claim
261 words
In a method for making waveguide fibers of high purity fused silica glass doped with an oxide dopant through the outside vapor deposition process comprising the steps of: (a) producing a gas stream containing a halide-free silicon-containing compound in vapor form capable of being converted through thermal decomposition with oxidation or flame hydrolysis to SiO 2 and a compound in vapor form capable of being converted through thermal decomposition with oxidation or flame hydrolysis to at least one member of the group consisting of P 2 O 5 and a metal oxide which has a metallic component selected from the Groups IA, IB, IIA, IIB, IIIA, IIIB, IVA, IVB, VA, and the rare earth series of the Periodic Table; (b) passing said gas stream into the flame of a combustion burner to form amorphous particles of high purity fused SiO 2 doped with an oxide dopant; (c) depositing said amorphous particles onto a mandrel; (d) consolidating said deposit of amorphous particles into a non-porous, transparent glass body; and (e) drawing optical waveguide fiber from said body; the improvement comprising utilizing as the halide-free, silicon-containing compound an organosilicon-R compound in vapor form selected from the group consisting of organosilicon-nitrogen compounds having a basic Si--N--Si structure, siloxasilazanes having a basic Si--N--Si--O--Si structure, and mixtures thereof having the following properties; (1) a Si--R bond dissociation energy that is no higher than the dissociation energy of the Si--O bond; (2) a boiling point no higher than 350° C.; and (3) which, upon pyrolysis and/or hydrolysis, will produce decomposition products beside SiO 2 which are non-toxic.
Claim 25
Dependent Claim
261 words
In a method for making waveguide fibers of high purity fused silica glass doped with an oxide dopant through the outside vapor deposition process comprising the steps of: (a) producing a gas stream containing a halide-free silicon-containing compound in vapor form capable of being converted through thermal decomposition with oxidation or flame hydrolysis to SiO 2 and a compound in vapor form capable of being converted through thermal decomposition with oxidation or flame hydrolysis to at least one member of the group consisting of P 2 O 5 and a metal oxide which has a metallic component selected from the Groups IA, IB, IIA, IIB, IIIA, IIIB, IVA, IVB, VA, and the rare earth series of the Periodic Table; (b) passing said gas stream into the flame of a combustion burner to form amorphous particles of high purity fused SiO 2 doped with an oxide dopant; (c) depositing said amorphous particles onto a mandrel; (d) consolidating said deposit of amorphous particles into a non-porous, transparent glass body; and (e) drawing optical waveguide fiber from said body; the improvement comprising utilizing as the halide-free, silicon-containing compound an organosilicon-R compound in vapor form selected from the group consisting of organosilicon-nitrogen compounds having a basic Si--N--Si structure, siloxasilazanes having a basic Si--N--Si--O--Si structure, and mixtures thereof having the following properties; (1) a Si--R bond dissociation energy that is no higher than the dissociation energy of the Si--O bond; (2) a boiling point no higher than 350° C.; and (3) which, upon pyrolysis and/or hydrolysis, will produce decomposition products beside SiO 2 which are non-toxic.
Claim 26
Dependent Claim
25 words
A method according to claim 21 wherein said organosilicon-nitrogen compound is selected from the group consisting of an aminosilane, a linear silazane, and a cyclosilazane.
Claim 27
Dependent Claim
22 words
A method according to claim 22 wherein said aminosilane is tris ketenimine, said linear silazane is nonamethyltrisilazane and said cyclosilazane is octamethylcyclotetrasilazane.
Claim 28
Dependent Claim
11 words
A method according to claim 21 wherein said siloxasilazane is hexamethylcyclotrisiloxazane.
Claim 29
Dependent Claim
16 words
A method according to claim 21 wherein said gas stream is comprised of an inert gas.
Claim 30
Dependent Claim
12 words
A method according to claim 25 wherein said inert gas is nitrogen.
Claim 31
Dependent Claim
65 words
A method according to claim 21 wherein said compound in vapor form capable of being converted to at least one member of the group consisting of P 2 O 5 and a metal oxide which has a metallic component selected from the Groups IA, IB, IIA, IIB, IIIA, IIIB, IVA, IVB, VA, and the rare earth series of the Periodic Table is a halide-containing compound.
Claim 32
Dependent Claim
65 words
A method according to claim 21 wherein said compound in vapor form capable of being converted to at least one member of the group consisting of P 2 O 5 and a metal oxide which has a metallic component selected from the Groups IA, IB, IIA, IIB, IIIA, IIIB, IVA, IVB, VA, and the rare earth series of the Periodic Table is a halide-containing compound.
Claim 33
Dependent Claim
197 words
In a method for making optical waveguide fibers of high purity fused silica glass through the axial vapor deposition process comprising the steps of: (a) producing a gas stream containing a halide-free silicon-containing compound in vapor form capable of being converted through thermal decomposition with oxidation or flame hydrolysis to SiO 2 ; (b) passing said gas stream into the flame of a combustion burner to form amorphous particles of high purity fused SiO 2 ; (c) depositing said amorphous particles onto a bait tube; (d) consolidating said deposit of amorphous particles into a non-porous, transparent glass body of high purity fused silica; and (e) drawing optical waveguide fiber from said body; the improvement comprising utilizing as the halide-free, silicon-containing compound an organosilicon-oxygen compound in vapor form selected from the group consisting of organosilicon-nitrogen compounds having a basic Si--N--Si structure, siloxasilazanes having a basic Si--N--Si--O--Si structure, and mixtures thereof having the following properties; (1) a Si--R bond dissociation energy that is no higher than the dissociation energy of the Si--O bond; (2) a boiling point no higher than 350° C.; and (3) which, upon pyrolysis and/or hydrolysis, will produce decomposition products beside SiO 2 which are non-toxic.
Claim 34
Dependent Claim
197 words
In a method for making optical waveguide fibers of high purity fused silica glass through the axial vapor deposition process comprising the steps of: (a) producing a gas stream containing a halide-free silicon-containing compound in vapor form capable of being converted through thermal decomposition with oxidation or flame hydrolysis to SiO 2 ; (b) passing said gas stream into the flame of a combustion burner to form amorphous particles of high purity fused SiO 2 ; (c) depositing said amorphous particles onto a bait tube; (d) consolidating said deposit of amorphous particles into a non-porous, transparent glass body of high purity fused silica; and (e) drawing optical waveguide fiber from said body; the improvement comprising utilizing as the halide-free, silicon-containing compound an organosilicon-oxygen compound in vapor form selected from the group consisting of organosilicon-nitrogen compounds having a basic Si--N--Si structure, siloxasilazanes having a basic Si--N--Si--O--Si structure, and mixtures thereof having the following properties; (1) a Si--R bond dissociation energy that is no higher than the dissociation energy of the Si--O bond; (2) a boiling point no higher than 350° C.; and (3) which, upon pyrolysis and/or hydrolysis, will produce decomposition products beside SiO 2 which are non-toxic.
Claim 35
Dependent Claim
24 words
A method according to claim 29 wherein said organosilicon-nitrogen compound is selected from the group consisting of an aminosilane, a silazane, and a cyclosilazane.
Claim 36
Dependent Claim
22 words
A method according to claim 30 wherein said aminosilane is tris ketenimine, said linear silazane is nonamethyltrisilazane and said cyclosilazane is octamethylcyclotetrasilazane.
Claim 37
Dependent Claim
11 words
A method according to claim 29 wherein said siloxasilazane is hexamethylcyclotrisiloxazane.
Claim 38
Dependent Claim
16 words
A method according to claim 29 wherein said gas stream is comprised of an inert gas.
Claim 39
Dependent Claim
12 words
A method according to claim 33 wherein said inert gas is nitrogen.
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