US4439265A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fabrication method for LiNbO3 and LiTaO3 integrated optics devices
Assignee: Agere Systems LLC
•
Filing: 1981-07-17
•
Granted: 1984-03-27
•
Expires: 2001-07-17
Abstract
Abstract A simple, inexpensive, and reliable technique for substantially preventing the unwanted formation of a surface guiding layer during manufacture of light-guiding structures in LiNbO 3 and LiTaO 3 substrates is disclosed. The technique involves addition of an effective amount of a gaseous hydrogen donor to the processing atmosphere during high-temperature processing. A particularly convenient hydrogen donor is water vapor, which can be added to the atmosphere by, for instance, bubbling of the feed gas through a water column. A partial pressure of more than about 9 Torr of H 2 O has been found effective in the practice of the technique.
Inventors
- 👤 Rodney C. Alferness
- 👤 Lawrence L. Buhl
- 👤 Janet L. Jackel
- 👤 Susan P. Lyman
- 👤 Vellayan Ramaswamy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 17:09
CPC Classifications
C; C30; C30B; C30B31/00; C30B31/02; C30B29/00; C30B29/10; C30B29/16; C30B29/22; C30B29/30
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
125 words
Method for manufacturing an optical device comprising an in-diffused strip lightguiding region in a substrate comprising material selected from the group consisting of LiNbO 3 and LiTaO 3 , the method comprising diffusing metal atoms into the substrate during a high-temperature diffusion step comprising heating the substrate to a temperature greater than about 700° C., characterized in that the method further comprises contacting at least part of the substrate with an atmosphere comprising at least a minimum effective concentration of a hydrogen donor, the contact occurring during at least part of the time the substrate is, during the diffusion step, at the temperature greater than about 700° C., thereby preventing a substantial decrease of the Li concentrations in the contacted surface region of the substrate.
Claim 2
Dependent Claim
125 words
Method for manufacturing an optical device comprising an in-diffused strip lightguiding region in a substrate comprising material selected from the group consisting of LiNbO 3 and LiTaO 3 , the method comprising diffusing metal atoms into the substrate during a high-temperature diffusion step comprising heating the substrate to a temperature greater than about 700° C., characterized in that the method further comprises contacting at least part of the substrate with an atmosphere comprising at least a minimum effective concentration of a hydrogen donor, the contact occurring during at least part of the time the substrate is, during the diffusion step, at the temperature greater than about 700° C., thereby preventing a substantial decrease of the Li concentrations in the contacted surface region of the substrate.
Claim 3
Dependent Claim
11 words
Method of claim 1, wherein the hydrogen donor is water vapor.
Claim 4
Dependent Claim
24 words
Method of claim 2, wherein the water vapor is added to the atmosphere by flowing a feed gas through a bubbler containing liquid water.
Claim 5
Dependent Claim
19 words
Method of claim 2, wherein the atmosphere comprises water vapor having a partial pressure of at least 9 Torr.
References Cited (Backward Citations)
JPS50154200A
Cited
US4082601A
Cited
JPS5253800A
Cited
JPS5365299A
Cited
JPS549174A
Cited
JPS549173A
Cited
JPS549171A
Cited
JPS5434159A
Cited
JPS5497585A
Cited
JPS5497584A
Cited
JPS5542238A
Cited
JPS56120600A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-03-27 | 1987-09-26 | 1988-03-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-03-27 | 1991-09-26 | 1992-03-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-03-27 | 1995-09-26 | 1996-03-27 | $7700.00 | Window Closed / Lapsed |