US3860467A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of etching a surface of a substrate comprising LITAO{HD 3 {B and chemically similar materials
Assignee: AT&T Inc
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Filing: 1974-02-22
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Granted: 1975-01-14
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Expires: 1994-02-22
Abstract
Abstract A method of etching a surface of a substrate comprising lithium tantalate (LiTaO3) and chemically similar materials is disclosed. The method includes contacting the surface with a mixture comprising hydrofluoric acid and sulfuric acid. In addition to its etching action, the mixture is also capable of polishing the thus treated surface.
Inventors
- 👤 Mahn-Jick Lim
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 19:48
CPC Classifications
C; C04; C04B; C04B41/00; C04B41/009; C04B41/53; C04B41/5338; C04B41/5353; C04B41/80; C04B41/91
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
51 words
A method of treating a body comprising lithium tantalate to obtain a polished surface thereof, which comprises contacting the surface with a mixture comprising HF present in an amount ranging from about 42.172 to about 47.535 molal and H2SO4 present in an amount ranging from about 40.173 to about 3.354 molal.
Claim 2
Independent Claim
46 words
A method of optically examining a substrate comprising LiTaO3 which comprises treating the substrate with a mixture comprising HF present in an amount ranging from about 42.172 molal to about 47.535 molal and H2SO4 present in an amount ranging from about 40.173 to about 3.354 molal.
Claim 3
Dependent Claim
18 words
The method as defined in claim 3 which further comprises directly examining said treated substrate with optical means.
References Cited (Backward Citations)
US1777321A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-01-13 | 1978-07-15 | 1979-01-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-01-13 | 1982-07-15 | 1983-01-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-01-13 | 1986-07-15 | 1987-01-14 | $7700.00 | Window Closed / Lapsed |