US4621277A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Semiconductor device having insulating film
Assignee: Fujitsu Ltd
•
Filing: 1982-04-28
•
Granted: 1986-11-04
•
Expires: 2002-04-28
Abstract
Abstract An insulative film, such as SiO 2 , Si 3 N 4 and PSG films, is commonly used, for example, the passivation film or to insulate the gate electrode of MISFETs. Stability of the insulative films during the production or operation of the semiconductor devices is enhanced by providing an insulative film which is formed by nitridation, for example, in an NH 3 gas, of an SiO 2 film, preferably a directly thermally oxidized film of silicon. The insulative film according to the present invention is used for a gate insulation film in MISFETs, a capacitor or passivation film for semiconductor devices, and as a mask for selectively forming circuit elements of semiconductor devices. The process for forming the insulative film may comprise successive nitridation, oxidation and nitridation steps.
Inventors
- 👤 Takashi Ito
- 👤 Takao Nozaki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 07:42
CPC Classifications
H; H10; H10P; H10P14/00; H10P14/60; H10P14/69; H10P14/692; H10P14/6921; H10P14/6922; H10P14/6927; H10B; H10B12/00; H10B12/01; H10B12/02; H10B12/03; H10B12/05; H10B12/30; H10D; H10D64/00; H10D64/01; H10D64/013; H10D64/01302; H10D64/01332; H10D64/01336; H10D64/01344; H10D64/60; H10D64/66; H10D64/68; H10D64/681; H10P14/63; H10P14/6302; H10P14/6319; H10P14/65; H10P14/6516; H10P14/6518; H10P14/6524; H10P14/6526; H10P14/6326; H10P14/6328; H10P14/6334; H10P14/66; H10P14/662; H10P14/69215; H10P14/6923; H10P14/694; H10P14/6943; H10P14/69433; Y; Y10; Y10S; Y10S148/00; Y10S148/043; Y10S148/112; Y10S148/114
Claims Analysis
Total Claims: 30
Claim 1
Independent Claim
54 words
A semiconductor device comprising a semiconductor silicon substrate, and an insulating film having its lower surface on said semiconductor silicon substrate, the upper surface of said insulating film comprising an at least partially nitridated surface portion of a silicon dioxide film, and said silicon dioxide film comprising a thermally oxidized portion of said substrate.
Claim 2
Dependent Claim
54 words
A semiconductor device comprising a semiconductor silicon substrate, and an insulating film having its lower surface on said semiconductor silicon substrate, the upper surface of said insulating film comprising an at least partially nitridated surface portion of a silicon dioxide film, and said silicon dioxide film comprising a thermally oxidized portion of said substrate.
Claim 3
Dependent Claim
27 words
A semiconductor device according to claim 1, wherein said semiconductor device comprises at least one MISFET element having a gate insulating film made of said insulating film.
Claim 4
Dependent Claim
23 words
A semiconductor device according to claim 2, wherein said insulating film has a thickness in the range from approximately 30 to 3000 angstroms.
Claim 5
Dependent Claim
58 words
A semiconductor device comprising a semiconductor silicon substrate, and an insulating film having its lower surface on said semiconductor silicon substrate, the upper surface of said insulating film comprising a nitridized surface portion of a silicon oxide film, and said silicon oxide film comprising an oxidized surface portion of a directly thermally nitridized portion of said semiconductor substrate.
Claim 6
Dependent Claim
58 words
A semiconductor device comprising a semiconductor silicon substrate, and an insulating film having its lower surface on said semiconductor silicon substrate, the upper surface of said insulating film comprising a nitridized surface portion of a silicon oxide film, and said silicon oxide film comprising an oxidized surface portion of a directly thermally nitridized portion of said semiconductor substrate.
Claim 7
Dependent Claim
27 words
A semiconductor device according to claim 4, wherein said semiconductor device comprises at least one MISFET element having a gate insulation film made of said insulating film.
Claim 8
Dependent Claim
24 words
A semiconductor device according to claim 4, wherein said gate insulating film has a thickness in the range from approximately 30 to 190 angstroms.
Claim 9
Dependent Claim
42 words
A semiconductor device according to claim 2, 3, 4, 5 or 6 wherein said insulating film has a surface state density in the range from approximately 5×10 11 to approximately 1×10 10 /cm 2 at a silicon surface potential of 0.3 eV.
Claim 10
Dependent Claim
47 words
A semiconductor device according to claim 2 or 5, wherein said semiconductor device further comprises a gate electrode formed on said gate insulation film, and said gate electrode comprises a material selected from the group consisting of aluminum, molybdenum, polycrystalline silicon, a metal silicide, chromium and titanium.
Claim 11
Dependent Claim
24 words
A semiconductor device according to claim 6, wherein said gate electrode comprises of a metal selected from the group consisting of aluminum and molybdenum.
Claim 12
Dependent Claim
23 words
A semiconductor device according to claim 2 or 5, wherein said insulating film comprises a field insulation film encompassing each said MISFET element.
Claim 13
Dependent Claim
42 words
A semiconductor device according to claim 2, wherein said semiconductor device comprises a further insulating film covering each said MISFET element, said further insulating film comprising a nitridated surface portion of a silicon dioxide film selectively formed on each said MISFET element.
Claim 14
Dependent Claim
23 words
A semiconductor device according to claim 2 or 5, wherein said semiconductor device comprises a selectively patterned metal layer on said insulating film.
Claim 15
Dependent Claim
45 words
A semiconductor device according to claim 1, wherein said semiconductor device comprises at least one capacitor element and said at least one capacitor element comprises: said insulating film as the dielectric material layer of said capacitor element, and a capacitor plate on said insulating film.
Claim 16
Dependent Claim
24 words
A semiconductor device according to claim 13, wherein said insulating film has a thickness in the range of from approximately 30 to 10,000 angstroms.
Claim 17
Dependent Claim
49 words
A semiconductor device according to claim 14, comprising at least one MISFET element which includes: a gate insulation film consisting essentially of silicon dioxide, formed by oxidizing said insulating film, a gate electrode of polycrystalline silicon, a further silicon dioxide film isolating said gate electrode from said capacitor plate.
Claim 18
Dependent Claim
33 words
A semiconductor device according to claim 15, wherein said further silicon dioxide film for isolating said capacitor plate from said gate electrode has a thickness in the range from 500 to 2000 angstroms.
Claim 19
Dependent Claim
70 words
A semiconductor device according to claim 13 wherein said semiconductor device further comprises at least one MISFET element, which element comprises a gate insulation film comprising an oxidized portion of said semiconductor silicon substrate, and a gate electrode of polycrystalline silicon, said capacitor plate comprising polycrystalline silicon and being isolated from said gate electrode by a film of silicon dioxide comprising an oxidized portion of said polycrystalline silicon capacitor plate.
Claim 20
Dependent Claim
46 words
A semiconductor device according to claim 1, 2, 4, 5 or 13, wherein at least an upper surface of said insulating film comprises silicon oxynitride, and the nitrogen content of the silicon oxynitride decreases gradually from said upper surface toward the interior of said insulation film.
Claim 21
Dependent Claim
65 words
A semiconductor device according to claim 1, 2, 4, 5, or 13, wherein at least an upper surface of said insulating film comprises silicon oxynitride, and the nitrogen content of the silicon oxynitride decreases gradually from said upper surface toward the interior of said insulating film, the molar ratio of nitrogen to oxygen in said silicon oxynitride being in the range from 1:10 to 10:1.
Claim 22
Dependent Claim
37 words
A device according to claim 5, wherein said semiconductor device comprises a further insulating film selectively covering said at least one MISFET element, said further insulating film comprising a nitridated surface portion of a silicon dioxide film.
Claim 23
Dependent Claim
42 words
A semiconductor device according to claim 18, wherein the surface state density of said insulating film is reduced to a value in the range from approximately 5×10 11 to approximately 1×10 10 /cm 2 at a silicon surface potential of 0.3 eV.
Claim 24
Dependent Claim
129 words
A semiconductor element comprising a semiconductor silicon substrate, at least one MISFET element in said substrate and having a gate insulating film over a portion thereof, a further insulating film covering a further portion of said MISFET element, metallic wiring covering said further insulating film covering the MISFET element, a capacitor element having an insulating layer as the dielectric layer, and a gate electrode on said gate insulating film of said at least one MISFET element, wherein at least one of said gate insulating film, said further insulating film and said insulating layer has its lower surface on said substrate and includes on its upper surface an at least partidally nitridated upper surface portion of a silicon dioxide film comprising a thermally oxidized upper surface portion of said substrate.
Claim 25
Dependent Claim
129 words
A semiconductor element comprising a semiconductor silicon substrate, at least one MISFET element in said substrate and having a gate insulating film over a portion thereof, a further insulating film covering a further portion of said MISFET element, metallic wiring covering said further insulating film covering the MISFET element, a capacitor element having an insulating layer as the dielectric layer, and a gate electrode on said gate insulating film of said at least one MISFET element, wherein at least one of said gate insulating film, said further insulating film and said insulating layer has its lower surface on said substrate and includes on its upper surface an at least partidally nitridated upper surface portion of a silicon dioxide film comprising a thermally oxidized upper surface portion of said substrate.
Claim 26
Dependent Claim
29 words
The element of claim 22, said thermally oxidized portion of the insulating film comprising a directly nitridized portion of said silicon substrate which has been subjected to thermal oxidation.
Claim 27
Independent Claim
23 words
The device of claims 1, 4, or 23, said insulating film comprising a dielectric constant in the range from approximately 4 to 5.3.
Claim 28
Dependent Claim
20 words
The device of claim 1, 4 or 22, said insulating film having a breakdown field strength of approximately 12 volts.
Claim 29
Dependent Claim
36 words
The device of claim 7, wherein said surface state density is with respect to a trap level in the proximity of the interface between the silicon substrate and the remaining portion of said silicon dioxide film.
Claim 30
Dependent Claim
36 words
The device of claim 21, wherein said surface state density is with respect to a trap level in the proximity of the interface between the silicon substrate and the remaining portion of said silicon dioxide film.
References Cited (Backward Citations)
US4113515A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-11-03 | 1990-05-05 | 1990-11-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-11-03 | 1994-05-05 | 1994-11-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-11-03 | 1998-05-05 | 1998-11-04 | $7700.00 | Window Closed / Lapsed |