Patent US2344203A successfully refreshed from Google Patents.
US5416352A
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Gate electrode formed on a region ranging from a gate insulating film to a field insulating film
Assignee: Fujitsu Semiconductor Ltd
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Filing: 1994-06-15
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Granted: 1995-05-16
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Expires: 2014-06-15
Abstract
Abstract The invention relates to a semiconductor device having an electrode formed on an region ranging from its thin insulating film in an element forming region to its thick insulating film in an isolation region, and it is an object of the invention to provide a semiconductor device capable of improving dielectric strength of a thin insulating film under a electrode in the boundary region between a thin insulating film and a thick insulating film as well as improving the film quality of the thin insulating film. A semiconductor device according to the present invention comprises a thick insulating film partly formed on a semiconductor substrate, a thin insulating film formed on the semiconductor substrate adjacent to the thick insulating film, a first electrode layer composed of a semiconductor layer which is formed in a region ranging from the thin insulating film to the thick insulating film and has a higher resistance in a boundary region between the thin insulating film and the thick insulating film and a lower resistance except for the boundary region, and a second electrode layer formed on the first electrode layer.
Inventors
- 👤 Kazuhiko Takada
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 01:35
CPC Classifications
H; H10; H10D; H10D64/00; H10D64/60; H10D64/66; H10D64/671
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
97 words
A semiconductor device comprising: a thick insulating film partly formed on a semiconductor substrate; an thin insulating film formed on the semiconductor substrate adjacent to the thick insulating film; a first electrode layer composed of a semiconductor layer which is formed in a region ranging from the thin insulating film to the thick insulating film and has a higher resistance in a boundary region between the thick insulating film and the thin insulating film and a lower resistance in a region except for the boundary region; and a second electrode layer formed on the first electrode layer.
Claim 2
Dependent Claim
97 words
A semiconductor device comprising: a thick insulating film partly formed on a semiconductor substrate; an thin insulating film formed on the semiconductor substrate adjacent to the thick insulating film; a first electrode layer composed of a semiconductor layer which is formed in a region ranging from the thin insulating film to the thick insulating film and has a higher resistance in a boundary region between the thick insulating film and the thin insulating film and a lower resistance in a region except for the boundary region; and a second electrode layer formed on the first electrode layer.
Claim 3
Dependent Claim
17 words
A semiconductor device according to claim 1, wherein the thin insulating film is a gate insulating film.
Claim 4
Dependent Claim
28 words
A semiconductor device according to claim 1, wherein a two-layered electrode layer composed of the first electrode layer and the second electrode layer is a gate electrode layer.
Claim 5
Dependent Claim
15 words
A semiconductor device according to claim 1, wherein the semiconductor substrate is a silicon substrate.
Claim 6
Dependent Claim
24 words
A semiconductor device according to claim 4, wherein the thick insulating film is a silicon oxide film formed by selectively oxidizing the silicon substrate.
Claim 7
Dependent Claim
23 words
A semiconductor device according to claim 4, wherein the thin insulating film is a silicon oxide film formed by oxidizing the silicon substrate.
Claim 8
Dependent Claim
30 words
A semiconductor device according to claim 1, wherein the first electrode layer is composed of one of a single-crystalline silicon film, a polycrystalline silicon film, and an amorphous silicon film.
Claim 9
Dependent Claim
38 words
A semiconductor device according to claim 1, wherein the second electrode layer is composed of one of a titanium silicide film, a tungsten silicide film, a molybdenum silicide film, a cobalt silicide film and a tantalum silicide film.
Claim 10
Dependent Claim
35 words
A semiconductor device according to claim 1, wherein the semiconductor layer is formed by selectively doping the semiconductor layer with conductive type impurities as masking the part of the semiconductor layer in the boundary region.
Claim 11
Dependent Claim
52 words
A semiconductor device according to claim 1, wherein the semiconductor layer is formed by doping the semiconductor layer with one conductive type impurities and then selectively doping the part of the semiconductor layer in the boundary region with counter conductive type impurities with lower density than the doped one conductive type impurities.
Claim 12
Dependent Claim
37 words
A semiconductor device according to claim 1, wherein the semiconductor layer in the boundary region is an intrinsic semiconductor layer or a semiconductor layer with lower carrier density than a semiconductor layer except for the boundary region.
Claim 13
Dependent Claim
44 words
A semiconductor device according to claim 11, wherein the intrinsic semiconductor layer or the semiconductor layer with lower carrier density is formed by selectively doping the semiconductor layer with conductive type impurities as masking the part of the semiconductor layer in the boundary region.
Claim 14
Dependent Claim
16 words
A semiconductor device according to claim 12, wherein the conductive type impurities are borons or phosphorouses.
Claim 15
Dependent Claim
38 words
A semiconductor device according to claim 13, wherein the second electrode layer is composed of one of a titanium silicide film, a tungsten silicide film, a molybdenum silicide film, a cobalt silicide film and a tantalum silicide film.
Claim 16
Dependent Claim
61 words
A semiconductor device according to claim 11, wherein the intrinsic semiconductor layer or the semiconductor layer with lower carrier density is formed by doping the semiconductor layer with one conductive type impurities and then selectively doping the part of the semiconductor layer in the boundary region with counter conductive type impurities with lower density than the doped one conductive type impurities.
Claim 17
Dependent Claim
27 words
A semiconductor device according to claim 15, wherein the one conductive type impurities are borons or phosphorouses and the counter conductive type impurities are phosphorouses or borons.
Claim 18
Dependent Claim
38 words
A semiconductor device according to claim 16, wherein the second electrode layer is composed of one of a titanium silicide film, a tungsten silicide film, a molybdenum silicide film, a cobalt silicide film and a tantalum silicide film.
References Cited (Backward Citations)
JPS55113375A
Cited
US4894689A
Cited
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