US4529474A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of cleaning apparatus for forming deposited film
Assignee: Canon Inc
•
Filing: 1984-01-30
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Granted: 1985-07-16
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Expires: 2004-01-30
Abstract
Abstract A method of cleaning an apparatus for forming deposited film on a substrate to remove the substances attached to the inside walls of a reaction chamber in the course of the formation of deposited film on the substrate by etching with plasma reaction comprises using a gas mixture of carbon tetrafluoride and oxygen as etchant.
Inventors
- 👤 Yasutomo Fujiyama
- 👤 Osamu Kamiya
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:35
CPC Classifications
C; C23; C23F; C23F4/00; C23C; C23C16/00; C23C16/44; C23C16/4401; C23C16/4405
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
75 words
A method of cleaning an apparatus for forming deposited film on a substrate to remove the substances attached to the inside walls of a reaction chamber in the course of the formation of deposited film on the substrate by etching with plasma reaction, which comprises using a gas mixture of carbon tetrafluoride and oxygen as ethant, wherein the partial pressure ratio of (O 2 /CF 4 ) in said gas mixture is 8 to 30%.
Claim 2
Independent Claim
75 words
A method of cleaning an apparatus for forming deposited film on a substrate to remove the substances attached to the inside walls of a reaction chamber in the course of the formation of deposited film on the substrate by etching with plasma reaction, which comprises using a gas mixture of carbon tetrafluoride and oxygen as ethant, wherein the partial pressure ratio of (O 2 /CF 4 ) in said gas mixture is 8 to 30%.
Claim 3
Dependent Claim
35 words
A method according to claim 1 wherein said gas mixture is introduced into the apparatus from a gas emitting inlet disposed on the inside of the end of the apparatus opposite to an evacuating outlet.
Claim 4
Dependent Claim
33 words
A method according to claim 1 wherein the region to be cleaned is controlled by changing the vacuum degree in the reaction chamber when said gas mixture is introduced into the reaction chamber.
References Cited (Backward Citations)
US4138306A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-07-15 | 1989-01-14 | 1989-07-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-07-15 | 1993-01-14 | 1993-07-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-07-15 | 1997-01-14 | 1997-07-16 | $7700.00 | Window Closed / Lapsed |