Patent US4505028A successfully refreshed from Google Patents.
US4505028A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of producing semiconductor device
Assignee: Hitachi Ltd
•
Filing: 1984-01-19
•
Granted: 1985-03-19
•
Expires: 2004-01-19
Abstract
Abstract A silicon wafer having a tungsten and/or molybdenum film formed on its surface is heat-treated in hydrogen containing water vapor. Thus, silicon can be selectively oxidized without substantially oxidizing tungsten and/or molybdenum.
Inventors
- 👤 Nobuyoshi Kobayashi
- 👤 Seiichi Iwata
- 👤 Naoki Yamamoto
- 👤 Hitoshi Matsuo
- 👤 Teiichi Homma
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 22:08
CPC Classifications
H; H10; H10D; H10D64/00; H10D64/01; H10D64/011; H10P; H10P14/00; H10P14/60; H10P14/63; H10P14/6302; H10P14/6304; H10P14/6306; H10P14/6308; H10P14/6309; H10P14/61; H10P14/6322; H10P14/69; H10P14/692; H10P14/6921; H10P14/69215; H10P30/00; H10P30/20; H10P30/22; H10P76/00; H10P76/40; H10P76/405; H10P95/00; H10W; H10W10/00; H10W10/01; H10W10/011; H10W10/012; H10W10/0125; H10W10/0126; H10W10/10; H10W10/13; Y; Y10; Y10S; Y10S438/00; Y10S438/909
Claims Analysis
Total Claims: 37
Claim 1
Independent Claim
61 words
A method of forming at least one of electrodes and interconnections of at least one of tungsten or molybdenum on a semiconductor substrate, including the step of selectively oxidizing the exposed surface of said semiconductor substrate, without substantially oxidizing said at least one of tungsten and molybdenum on the substrate, by carrying out heat-treatment in a hydrogen atmosphere containing water vapor.
Claim 2
Independent Claim
61 words
A method of forming at least one of electrodes and interconnections of at least one of tungsten or molybdenum on a semiconductor substrate, including the step of selectively oxidizing the exposed surface of said semiconductor substrate, without substantially oxidizing said at least one of tungsten and molybdenum on the substrate, by carrying out heat-treatment in a hydrogen atmosphere containing water vapor.
Claim 3
Dependent Claim
13 words
The method of claim 1 wherein said semiconductor substrate is made of silicon.
Claim 4
Dependent Claim
14 words
The method of claim 1, wherein the heat-treating temperature is from 400° C.-1200° C.
Claim 5
Dependent Claim
45 words
The method of claim 1, wherein the partial pressure ratio between said water vapor and said hydrogen gas in said heat-treatment and the heat-treating temperature are selected as the values falling in the range between the curve b and the curve c of FIG. 1.
Claim 6
Dependent Claim
56 words
The method of claim 1, wherein the at least one of electrodes and interconnectons are of tungsten, and the partial pressure ratio between said vapor and said hydrogen gas in said heat-treatment and the heat-treating temperature are selected as the values falling in the range between the curve a and the curve c of FIG. 1.
Claim 7
Dependent Claim
41 words
The method of claim 1, wherein the partial pressure ratio of the water vapor and hydrogen, and the heat-treatment temperature, are selected such that only the semiconductor substrate surface is oxidized, without oxidizing the at least one of tungsten and molybdenum.
Claim 8
Independent Claim
35 words
A method of producing a semiconductor device including the step of selectively oxidizing silicon without substantially oxidizing at least one of tungsten and molybdenum by carrying out heat-treatment in a hydrogen atmosphere containing water vapor.
Claim 9
Independent Claim
35 words
A method of producing a semiconductor device including the step of selectively oxidizing silicon without substantially oxidizing at least one of tungsten and molybdenum by carrying out heat-treatment in a hydrogen atmosphere containing water vapor.
Claim 10
Dependent Claim
29 words
The method of producing a semiconductor device as defined in claim 7, wherein said silicon is single crystal silicon, polycrystalline silicon or silicon contained in tungsten or molybdenum silicides.
Claim 11
Dependent Claim
52 words
The method of producing a semiconductor device as claimed in claim 8, wherein the partial pressure ratio between said water vapor and said hydrogan gas in said heat-treatment and the heat-treating temperature are selected as the values falling in the range between the curve b and the curve c of FIG. 1.
Claim 12
Dependent Claim
23 words
The method of producing a semiconductor device as defined in claim 9, wherein the heat-treating temperature is from 400° C. to 1,200° C.
Claim 13
Dependent Claim
64 words
The method of producing a semiconductor device as in claim 7, wherein the heat treatment is carried out in the presence of tungsten, and wherein the partial pressure ratio between said water vapor and said hydrogen gas in said heat-treatment and the heat-treating temperature are selected as the values falling in the range between the curve a and the curve c of FIG. 1.
Claim 14
Dependent Claim
48 words
The method of producing a semiconductor device as defined in claim 7, wherein the partial pressure ratio of the water vapor and hydrogen, and the heat-treatment temperature, are selected such that only the semiconductor substrate surface is oxidized, without oxidizing the at least one of tungsten and molybdenum.
Claim 15
Independent Claim
131 words
A method of producing a semiconductor device including the steps of: (a) forming an insulating film on a semiconductor substrate of a first conductivity type; (b) forming at least one of a tungsten and molybdenum film having a desired shape at a desired portion on said insulating film; (c) doping an impurity having a conductivity type opposite to that of said semiconductor substrate to the surface region of said semiconductor substrate using said at least one of tungsten and molybdenum film as a mask; and (d) carrying out heat-treatment in hydrogen gas containing water vapor so as to selectively oxidize the surface of said semiconductor substrate where said at least one of tungsten and molybdenum film is not deposited without substantially oxidizing said at least one of tungsten and molybdenum film.
Claim 16
Independent Claim
131 words
A method of producing a semiconductor device including the steps of: (a) forming an insulating film on a semiconductor substrate of a first conductivity type; (b) forming at least one of a tungsten and molybdenum film having a desired shape at a desired portion on said insulating film; (c) doping an impurity having a conductivity type opposite to that of said semiconductor substrate to the surface region of said semiconductor substrate using said at least one of tungsten and molybdenum film as a mask; and (d) carrying out heat-treatment in hydrogen gas containing water vapor so as to selectively oxidize the surface of said semiconductor substrate where said at least one of tungsten and molybdenum film is not deposited without substantially oxidizing said at least one of tungsten and molybdenum film.
Claim 17
Dependent Claim
40 words
The method of producing a semiconductor device as defined in claim 13, wherein doping of said impurity is carried out by laminating a mask film on said at least one of tungsten and molybdenum film and then effecting ion implantation.
Claim 18
Dependent Claim
47 words
The method of producing a semiconductor device as defined in claim 14, wherein said mask film consists of at least one member selected from the group consisting of a polycrystalline silicon film, a phosphosilicate glass film, an SiO 2 film and an Si 3 N 4 film.
Claim 19
Dependent Claim
52 words
The method of producing a semiconductor device as defined in claim 13, wherein the partial pressure ratio between said water vapor and said hydrogen gas in said heat-treatment and the heat-treating temperature are selected as the values falling in the range between the curve b and the curve c of FIG. 1.
Claim 20
Dependent Claim
25 words
The method of producing a semiconductor device as defined in claim 16, wherein the heat-treating temperature is from about 400° C. to about 1,200° C.
Claim 21
Dependent Claim
62 words
The method of producing a semiconductor device as defined in claim 13, wherein a tungsten film is formed in step (b), and wherein the partial pressure ratio between said water vapor and said hydrogen gas in said heat-treatment and the heat-treating temperature are selected as the values falling in the range between the curve a and the curve c of FIG. 1.
Claim 22
Dependent Claim
48 words
The method of producing a semiconductor device as defined in claim 13, wherein the partial pressure ratio of the water vapor and hydrogen, and the heat-treatment temperature, are selected such that only the semiconductor substrate surface is oxidized, without oxidizing the at least one of tungsten and molybdenum.
Claim 23
Dependent Claim
21 words
The method of producing a semiconductor device as defined in claim 13, wherein said insulating film is an SiO 2 film.
Claim 24
Dependent Claim
20 words
The method of producing a semiconductor device as defined in claim 20, wherein said semiconductor substrate is made of silicon.
Claim 25
Dependent Claim
54 words
The method of producing a semiconductor device as defined in claim 13, wherein said forming at least one of tungsten and molybdenum film having a desired shape provides an exposed portion of said insulating film, and wherein said heat-treatment is carried out after the exposed portion of said insulating film is removed by etching.
Claim 26
Dependent Claim
51 words
The method of producing a semiconductor device as defined in claim 13, wherein said forming at least one of tungsten and molybdenum film having a desired shape provides an exposed portion of said insulating film, and wherein said heat-treatment is carried out without removing the exposed portion of said insulating film.
Claim 27
Dependent Claim
33 words
The method of producing a semiconductor device as defined in claim 13, wherein said at least one of tungsten and molybdenum film is the gate electrode of an MIS field effect semiconductor device.
Claim 28
Independent Claim
95 words
A method of producing a semiconductor device including the steps of: (a) forming an insulating film on a semiconductor substrate; (b) laminating at least one of tungsten and molybdenum film on said insulating film; (c) removing a desired portion of said at least one of tungsten and molybdenum film by etching; and (d) carrying out heat-treatment in hydrogen gas containing water vapor to oxidize the surface of said semiconductor substrate where said at least one of tungsten and molybdenum film is not deposited, without substantially oxiding said at least one of tungsten and molybdenum film.
Claim 29
Independent Claim
95 words
A method of producing a semiconductor device including the steps of: (a) forming an insulating film on a semiconductor substrate; (b) laminating at least one of tungsten and molybdenum film on said insulating film; (c) removing a desired portion of said at least one of tungsten and molybdenum film by etching; and (d) carrying out heat-treatment in hydrogen gas containing water vapor to oxidize the surface of said semiconductor substrate where said at least one of tungsten and molybdenum film is not deposited, without substantially oxiding said at least one of tungsten and molybdenum film.
Claim 30
Dependent Claim
55 words
The method of producing a semiconductor device as defined in claim 25, wherein said removing a desired portion of said at least one of tungsten and molybdenum film provides an exposed portion of said insulating film, and wherein said heat-treatment is carried out after the exposed portion of said insulating film is removed by etching.
Claim 31
Dependent Claim
48 words
The method of producing a semiconductor device as defined in claim 25, wherein said removing a desired portion of said at least one of tungsten and molybdenum film provides an exposed portion of said insulating film, and wherein said heat-treatment is carried out without removing said insulating film.
Claim 32
Dependent Claim
51 words
The method of producing a semiconductor device as defined in claim 25, wherein the partial pressure ratio between said vapor and said hydrogen gas in said heat-treatment and the heat-treating temperature are selected as the values falling in the range between the curve b and the curve c of FIG. 1.
Claim 33
Dependent Claim
25 words
The method of producing a semiconductor device as defined in claim 28, wherein the heat-treating temperature is from about 400° C. to about 1,200° C.
Claim 34
Dependent Claim
60 words
The method of producing a semiconductor device as defined in claim 25, wherein tungsten is laminated in step (b), and wherein the partial pressure ratio between said water vapor and said hydrogen gas in said heat-treatment and the heat-treating temperature are selected as the values falling in the range between the curve a and the curve c of FIG. 1.
Claim 35
Dependent Claim
48 words
The method of producing a semiconductor device as defined in claim 25, wherein the partial pressure ratio of the water vapor and hydrogen, and the heat-treatment temperature, are selected such that only the semiconductor substrate surface is oxidized, without oxidizing the at least one of tungsten and molybdenum.
Claim 36
Dependent Claim
22 words
The method of producing a semiconductor device as defined in claim 25, wherein said insulating film is made of SiO 2 .
Claim 37
Dependent Claim
20 words
The method of producing a semiconductor device as defined in claim 32, wherein said semiconductor substrate is made of silicon.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-03-18 | 1988-09-17 | 1989-03-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-03-18 | 1992-09-17 | 1993-03-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-03-18 | 1996-09-17 | 1997-03-19 | $7700.00 | Window Closed / Lapsed |