US4058638A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of optical thin film coating
Assignee: Texas Instruments Inc
•
Filing: 1975-11-03
•
Granted: 1977-11-15
•
Expires: 1995-11-03
Abstract
Abstract Disclosed is an improved optical thin film coating system comprising all essential elements of resistive and electron beam evaporation systems, chemical vapor deposition systems and reactive plasma deposition systems. Sequences of cleaning and deposition processes which previously required moving substrates through several chambers are performed in a single vacuum chamber. The evaporative sources also efficiently vaporize solid materials to provide reactive gases for reactive plasma and chemical vapor deposition processes, which were previously difficult or impossible to perform. Substrate movement, masking, and monitoring means previously used with evaporative sources are used to control thickness and uniformity of films deposited by chemical vapor and reactive plasma processes, to provide optical quality films.
Inventors
- 👤 Dale E. Morton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 03:01
CPC Classifications
C; C23; C23C; C23C14/00; C23C14/06; C23C14/0623; C23C14/0694; C23C16/00; C23C16/22; C23C16/30; C23C16/301; C23C16/305; C23C16/306; C23C16/34; C23C16/342; C23C16/44; C23C16/50; C23C16/505; Y; Y10; Y10S; Y10S359/00; Y10S359/90
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
182 words
A process for depositing an optical thin film coating on a substrate comprising the steps of: exposing said substrate in an evacuated chamber to an atmosphere containing arsine and a volatile gallium compound, while generating an RF field having an energy sufficient to yield a plasma at the substrate surface, thereby depositing a gallium arsenide coating on said substrate; then, without breaking said vacuum, exposing said coated sustrate to an atmosphere containing hydrogen sulfide and a zinc compound vapor while generating an RF field at the substrate surface having an energy sufficient to cause deposition of a zinc sulfide layer on said gallium arsenide coating; then, without breaking said vacuum, exposing said zinc sulfide layer to vapors of thorium flouride thereby forming a thorium flouride layer on said zinc sulfide layer; then, without breaking said vacuum, exposing said thorium flouride layer to an atmosphere containing a volatile boron compound and ammonia, while generating an RF field at the thorium flouride surface having an energy level sufficient to yield a plasma, and thereby deposit a boron nitride coating on said thorium fluoride layer.
Claim 2
Dependent Claim
182 words
A process for depositing an optical thin film coating on a substrate comprising the steps of: exposing said substrate in an evacuated chamber to an atmosphere containing arsine and a volatile gallium compound, while generating an RF field having an energy sufficient to yield a plasma at the substrate surface, thereby depositing a gallium arsenide coating on said substrate; then, without breaking said vacuum, exposing said coated sustrate to an atmosphere containing hydrogen sulfide and a zinc compound vapor while generating an RF field at the substrate surface having an energy sufficient to cause deposition of a zinc sulfide layer on said gallium arsenide coating; then, without breaking said vacuum, exposing said zinc sulfide layer to vapors of thorium flouride thereby forming a thorium flouride layer on said zinc sulfide layer; then, without breaking said vacuum, exposing said thorium flouride layer to an atmosphere containing a volatile boron compound and ammonia, while generating an RF field at the thorium flouride surface having an energy level sufficient to yield a plasma, and thereby deposit a boron nitride coating on said thorium fluoride layer.
Claim 3
Dependent Claim
13 words
A process as in claim 1 wherein said substrate is a germanium window.
Claim 4
Dependent Claim
12 words
A process as in claim 2 wherein said gallium compound is tetramethylgallium.
Claim 5
Dependent Claim
13 words
A process as in claim 3 wherein said zinc compound is zinc chloride.
Claim 6
Dependent Claim
12 words
A process as in claim 4 wherein said boron compound is diborane.
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) | 1980-11-14 | 1981-05-16 | 1981-11-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-11-14 | 1985-05-16 | 1985-11-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-11-14 | 1989-05-16 | 1989-11-15 | $7700.00 | Window Closed / Lapsed |