US4699825A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of forming silicon nitride film and product
Assignee: Hitachi Ltd
•
Filing: 1985-11-14
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Granted: 1987-10-13
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Expires: 2005-11-14
Abstract
Abstract In forming a silicon nitride film by the low-pressure CVD method using a silane gas and ammonia, the reaction pressure is set to lie over a range of from about 0.05 to about 0.25 Torr, enabling a silicon nitride film to be formed, of uniform thickness, highly efficiently even on large wafers, and maintaining high yield, improved uniformity and good quality as a whole without decreasing the film-forming efficiency. Preferably, the reaction pressure is maintained over a range of from 0.1 to 0.2 Torr to further increase the efficiency, while preferably maintaining the temperature over a range of from 700° to 1000° C.
Inventors
- 👤 Hideo Sakai
- 👤 Tetsuya Mizutani
- 👤 Takeo Yoshimi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 21:38
CPC Classifications
C; C23; C23C; C23C16/00; C23C16/22; C23C16/30; C23C16/34; C23C16/345; Y; Y10; Y10T; Y10T428/00; Y10T428/26; Y10T428/266
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
91 words
A method of forming a silicon nitride film on a plurality of wafers positioned in a reaction chamber, said plurality of wafers being positioned parallel to each other and each of said plurality of wafers measuring equal to or greater than 100 mm in diameter, by a chemical vapor deposition process provided by reacting a silane gas with ammonia under a low pressure, wherein the reaction is carried out under a pressure ranging from about 0.05 to about 0.25 Torr and at a temperature ranging from 650° C. to 1000° C.
Claim 2
Independent Claim
91 words
A method of forming a silicon nitride film on a plurality of wafers positioned in a reaction chamber, said plurality of wafers being positioned parallel to each other and each of said plurality of wafers measuring equal to or greater than 100 mm in diameter, by a chemical vapor deposition process provided by reacting a silane gas with ammonia under a low pressure, wherein the reaction is carried out under a pressure ranging from about 0.05 to about 0.25 Torr and at a temperature ranging from 650° C. to 1000° C.
Claim 3
Dependent Claim
27 words
A method of forming a silicon nitride film according to claim 1, wherein the reaction is carried out under a pressure ranging from 0.1 to 0.2 Torr.
Claim 4
Dependent Claim
28 words
A method of forming a silicon nitride film according to claim 2, wherein the reaction is carried out at a temperature ranging from about 700° to 1000° C.
Claim 5
Dependent Claim
29 words
A method of forming a silicon nitride film according to claim 3, wherein the silicon nitride film is formed on wafers each measuring 100 to 150 mm in diameter.
Claim 6
Dependent Claim
18 words
A method of forming a silicon nitride film according to claim 4, wherein the wafers are silicon wafers.
Claim 7
Dependent Claim
29 words
A method of forming a silicon nitride film according to claim 1, wherein the silicon nitride film is formed on wafers each measuring 100 to 150 mm in diameter.
Claim 8
Dependent Claim
48 words
A method of forming a silicon nitride film according to claim 1, wherein the silane gas is selected from the group consisting of SiH 3 Cl, SiH 2 Cl 2 , SiHCl 3 , SiCl 4 , SiH 4 , Si 2 H 6 and Si 3 H.sub..
Claim 9
Dependent Claim
59 words
A method of forming a silicon nitride film according to claim 1, wherein the silane gas and ammonia which react to form the silicon nitride film flow through said reaction chamber, with the plurality of wafers being positioned so as to be at least about perpendicular to the flow of the silane gas and ammonia through the reaction chamber.
Claim 10
Dependent Claim
24 words
A method of forming a silicon nitride film according to claim 8, wherein adjacent surfaces of adjacent wafers are spaced at least 4.75 mm.
Claim 11
Dependent Claim
25 words
A method of forming a silicon nitride film according to claim 9, wherein said plurality of wafers each measure 100 to 150 mm in diameter.
Claim 12
Dependent Claim
24 words
A method of forming a silicon nitride film according to claim 1, wherein adjacent surfaces of adjacent wafers are spaced at least 4.75 mm.
Claim 13
Dependent Claim
25 words
A method of forming a silicon nitride film according to claim 11, wherein said plurality of wafers each measure 100 to 150 mm in diameter.
Claim 14
Dependent Claim
8 words
Product formed by the process of claim 1.
Claim 15
Dependent Claim
8 words
Product formed by the process of claim 6.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-10-12 | 1991-04-13 | 1991-10-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-10-12 | 1995-04-13 | 1995-10-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-10-12 | 1999-04-13 | 1999-10-13 | $7700.00 | Window Closed / Lapsed |