US5019526A
Expired / Lapsed
US
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Method of manufacturing a semiconductor device having a plurality of elements
Assignee: Denso Corp
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Filing: 1988-09-26
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Granted: 1991-05-28
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Expires: 2008-09-26
Abstract
Abstract A method of manufacturing a semiconductor apparatus having a plurality of elements formed on a substrate comprises forming a pad oxidized film on the surface of the semiconductor substrate, forming a pattern of silicon nitride film to coat device areas on the pad oxidized film, and injecting boron ions into that surface of the pad oxidized film where no silicon nitride film is present, thereby to form a channel stopper region. Using the pattern of the silicon nitride film as a mask, a heat oxidized film is then formed on an elements separating region by heat oxidization, and ions of Si, N, C, or the like are injected into the surface of the heat oxidized film with such an acceleration energy that the ions are not injected into the silicon nitride film thereby to change the quality of the heat oxidized film. The silicon nitride film is removed by etching and the heat oxidized film is etching-treated by a solution of the hydrofluoric acid group to etching-remove particularly the bird's beak portions each of which is present along and under the peripheral rim of an element area of the silicon nitride film.
Inventors
- 👤 Hiroyuki Yamane
- 👤 Yasushi Higuchi
- 👤 Tetsuo Fujii
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 19:55
CPC Classifications
H; H10; H10P; H10P50/00; H10P50/20; H10P50/28; H10P50/282; H10P50/283; H10W; H10W10/00; H10W10/01; H10W10/011; H10W10/012; H10W10/0125; H10W10/0126; H10W10/10; H10W10/13; Y; Y10; Y10S; Y10S148/00; Y10S148/117; Y10S438/00; Y10S438/911
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
171 words
A method of manufacturing a semiconductor device having a semiconductor substrate and a plurality of elements formed on the substrate, said method comprising the steps of: oxidizing the entire surface of the semiconductor substrate, thereby forming a pad oxide film thereon; forming a pattern of silicon nitride film on those parts of the pad oxide film where the elements will be formed; forming a heat oxide film on those parts of the pad oxide film which are exposed; injecting ions selected from the group consisting of Si, N and C into the surface of the heat oxide film with such an acceleration energy that the ions do not pass through the silicon nitride film, thereby to change the quality of the heat oxide film to form a reformed layer; removing the pattern of silicon nitride film by means of a first etching process; and etching a part of the heat oxide film, excluding the region where the reformed layer has been formed, by a second etching process using an acid solution.
Claim 2
Independent Claim
171 words
A method of manufacturing a semiconductor device having a semiconductor substrate and a plurality of elements formed on the substrate, said method comprising the steps of: oxidizing the entire surface of the semiconductor substrate, thereby forming a pad oxide film thereon; forming a pattern of silicon nitride film on those parts of the pad oxide film where the elements will be formed; forming a heat oxide film on those parts of the pad oxide film which are exposed; injecting ions selected from the group consisting of Si, N and C into the surface of the heat oxide film with such an acceleration energy that the ions do not pass through the silicon nitride film, thereby to change the quality of the heat oxide film to form a reformed layer; removing the pattern of silicon nitride film by means of a first etching process; and etching a part of the heat oxide film, excluding the region where the reformed layer has been formed, by a second etching process using an acid solution.
Claim 3
Dependent Claim
28 words
The method according to claim 1, whereby ions of Si are injected into the surface of the heat oxide film, in the process of forming the reformed layer.
Claim 4
Dependent Claim
28 words
The method according to claim 1, whereby ions of N are injected into the surface of the heat oxide film, in the process of forming the reformed layer.
Claim 5
Dependent Claim
28 words
The method according to claim 1, whereby ions of C are injected into the surface of the heat oxide film, in the process of forming the reformed layer.
Claim 6
Dependent Claim
62 words
The method according to claim 1, whereby a plurality of bird's beak portions of the heat oxide film are formed, each of said portions entering along and under the peripheral rim of an element area of silicon nitride film, in the process of forming the heat oxide film, and no reformed layer is formed on the surface of the bird's beak portions.
Claim 7
Dependent Claim
68 words
The method according to claim 1, whereby a plurality of bird's beak portions of the heat oxide film are formed, each of said portions entering along and under the peripheral rim of an element area of silicon nitride film, in the process of forming the heat oxide film, and the bird's beak portions on which no reformed layer is formed are selectively etched in the second etching process.
Claim 8
Dependent Claim
43 words
The method according to claim 1, further comprising injecting boron ions, using the pattern of silicon nitride film as a mask, to form P + °type channel stopper region at that part of the semiconductor substrate where no silicon nitride film is present.
Claim 9
Independent Claim
213 words
A method of manufacturing a semiconductor device having a semiconductor substrate and a plurality of elements formed on the substrate, said method comprising the steps of: oxidizing the entire surface of the semiconductor substrate, thereby forming a pad oxide film thereon; forming a pattern of silicon nitride film on those parts of the pad oxide film where the elements will be formed; forming a heat oxide film on those parts of the pad oxide film which are exposed; injecting ions selected from the group consisting of Si, N and C into the surface of the heat oxide film with such an acceleration energy that the ions do not pass through the silicon nitride film, thereby forming a reformed layer having a quality which is changed such that, when the heat oxide film is etched with use of an etchant, an etching rate of the region where the ions have been injected becomes smaller than the etching rate of the region where the ions have not been injected; removing the pattern of the silicon nitride film by means of a first etching process; and etching a part of the heat oxide film with use of said etchant, excluding the part where the reformed layer has been formed, by means of a second etching process.
Claim 10
Independent Claim
213 words
A method of manufacturing a semiconductor device having a semiconductor substrate and a plurality of elements formed on the substrate, said method comprising the steps of: oxidizing the entire surface of the semiconductor substrate, thereby forming a pad oxide film thereon; forming a pattern of silicon nitride film on those parts of the pad oxide film where the elements will be formed; forming a heat oxide film on those parts of the pad oxide film which are exposed; injecting ions selected from the group consisting of Si, N and C into the surface of the heat oxide film with such an acceleration energy that the ions do not pass through the silicon nitride film, thereby forming a reformed layer having a quality which is changed such that, when the heat oxide film is etched with use of an etchant, an etching rate of the region where the ions have been injected becomes smaller than the etching rate of the region where the ions have not been injected; removing the pattern of the silicon nitride film by means of a first etching process; and etching a part of the heat oxide film with use of said etchant, excluding the part where the reformed layer has been formed, by means of a second etching process.
Claim 11
Dependent Claim
62 words
The method according to claim 8, whereby a plurality of bird's beak portions of the heat oxide film are formed, each of said portions entering along and under a peripheral rim of an element area of silicon nitride film, in the process of forming the heat oxide film, and no reformed layer is formed in the surface of the bird's beak portions.
Claim 12
Dependent Claim
67 words
The method according to claim 8, whereby a plurality of bird's beak portions of the heat oxide film are formed, each of said portions entering along and under the peripheral rim of an element area of silicon nitride film, in the process of forming the heat oxide film, and the bird's beak portions on which no reformed layer is formed are selectively etched in said etching process.
Claim 13
Dependent Claim
44 words
The method according to claim 8, further comprising injecting boron ions using the pattern of silicon nitride film as a mask, to form a P + type channel stopper region at that part of the semiconductor substrate where no silicon nitride film is present.
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