EP0081226A2
Expired / Lapsed
EP
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Method of making semiconductor device
Assignee: Panasonic Holdings Corp
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Filing: 1982-12-06
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Granted: —
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Expires: 2002-12-06
Abstract
Abstract A semiconductor device having phosphosilicate glass layer 6 is improved by adopting a new structure having a thin silicon nitride film 9 of a thickness lower than 3000 A provided under such place that is to be covered by the phosphosilicate glass 6. The phosphosilicate glass 6 is subject to softening after necessary selective etching. Undesirable oxidation of silicon layer 4 at the part under the phosphosilicate glass film in a thermal treatment for the softening is suppressed. Accordingly, in a MOS IC, which uses polycrystalline silicon film 4 as gate electrode and as wiring conductors, the silicon nitride film 9 is formed to cover the polycrystalllne silicon films 4, thereby undesirable oxidation of surface of the polycrystalline silicon film 4 is prevented, thereby shrink of pattern and/or forming of undesirable silicon oxide film around the gate electrode or wiring conductors are prevented.
Inventors
- 👤 Shuichi Mayumi
- 👤 Kunihiko Asahi
- 👤 Ichizo Kamei
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-01 12:55
CPC Classifications
H; H10; H10W; H10W20/00; H10W20/01; H10W20/071; H10W20/081; H10W20/082; H10P; H10P95/00; H10P14/00; H10P14/60; H10P14/69; H10P14/692; H10P14/6921; H10P14/6922; H10P14/6923; H10P14/694; H10P14/6943; H10P14/69433
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
87 words
Method of making semiconductor device comprising the steps of: forming a silicon nitride film on a semiconductor substrate, forming a phosphosilicate glass film at least on selected part on said silicon nitride film, boring contacting opening on selected parts of said phosphosilicate glass film retaining said silicon nitride film thereunder, softening said phosphosilicate glass film to reflow it for smoothing edges thereof, and removing by etching said silicon nitride film exposed from said openings and forming at least a connection conductor film on said phosphosilicate glass film.
Claim 2
Dependent Claim
87 words
Method of making semiconductor device comprising the steps of: forming a silicon nitride film on a semiconductor substrate, forming a phosphosilicate glass film at least on selected part on said silicon nitride film, boring contacting opening on selected parts of said phosphosilicate glass film retaining said silicon nitride film thereunder, softening said phosphosilicate glass film to reflow it for smoothing edges thereof, and removing by etching said silicon nitride film exposed from said openings and forming at least a connection conductor film on said phosphosilicate glass film.
Claim 3
Dependent Claim
27 words
Method of making semiconductor device in accordance with claim 1, wherein said.silicon nitride film is formed to be thinner than 3000 Å and thicker than 300 A.
Claim 4
Dependent Claim
47 words
Method of making semiconductor device in accordance with claim 1 or 2 which further comprising the steps of: prior to forming of said silicon nitride film, forming an electrode conductor of polycrystalline silicon film, and said silicon nitride film covering said electrode conductor of polycrystalline silicon film.
Claim 5
Dependent Claim
24 words
Method of making semiconductor device in accordance with claim 1 or 2, wherein phosphorous concentration in said phosphosilicate glass film is less than 8%.
Claim 6
Dependent Claim
38 words
Method of making semiconductor device in accordance with claim 1 or 2, wherein said smoothing is made by heat treatment of said phosphosilicate glass film in a high pressure water gas of a temperature of 900°C or lower.
Claim 7
Dependent Claim
53 words
Method of making semiconductor device in accordance with claim 1 or 2, wherein prior to forming of said silicon nitride film a silicon oxide film is formed at selected part under said silicon nitride film, and said silicon oxide film is etched by a mixed aqueous solution of hydrofluoric acid and ammonium fluoride.
Claim 8
Dependent Claim
39 words
Method of making semiconductor device in accordance with claim 6, wherein said mixed aqueous solution is a mixture of 1 volume part of hydrofluoric acid of about 50% concentration and 6 to 20 volume parts of 40% ammonium fluoride.
Claim 9
Dependent Claim
22 words
Method of making semiconductor device in accordance with claim 7, wherein said etching is made at 20°C for 45 to 70 seconds.
Claim 10
Dependent Claim
60 words
A semiconductor device comprising: a semiconductor substrate, a silicon nitride film formed on selected parts of said semiconductor substrate, a phosphosilicate glass film formed on selected parts of said semiconductor substrate to cover at least selected parts of said silicon nitride film and having reflow smoothed edges, and at least a connection conductor film formed on said phosphosilicate glass film.
Claim 11
Dependent Claim
60 words
A semiconductor device comprising: a semiconductor substrate, a silicon nitride film formed on selected parts of said semiconductor substrate, a phosphosilicate glass film formed on selected parts of said semiconductor substrate to cover at least selected parts of said silicon nitride film and having reflow smoothed edges, and at least a connection conductor film formed on said phosphosilicate glass film.
Claim 12
Dependent Claim
23 words
A semiconductor device in accordance with claim 9, wherein said silicon nitride film is thinner than 3000 A and thicker than 300 A.
Claim 13
Dependent Claim
21 words
A semiconductor device in accordance with claim 9 or 10, wherein said semiconductor substrate has an electrode conductor of polycrystalline film.
Claim 14
Dependent Claim
25 words
A semiconductor device in accordance with claim 9 or 10, wherein phosphorous concentration in said phosphocilicate glass film has phosphorous concentration of less than 8%.
References Cited (Backward Citations)
No citation records indexed.
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