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US3808068A
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Differential etching of garnet materials
Assignee: AT&T Inc
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Filing: 1972-12-11
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Granted: 1974-04-30
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Expires: 1992-12-11
Abstract
Abstract A method for etching selected areas of single crystal garnets. The crystal is subjected to an ion implantation in the area to be etched. A proper etching solution is then applied to the crystal. The damaged area formed by the ion implantation will etch at a significantly greater rate than the remainder of the material. The process is self-limiting since the depth to which the crystal is etched is dependent upon the depth of the implantation and not upon the etching temperature or the length of time the etchant is applied. The differential etching rate also eliminates undesirable undercutting which usually results from the use of masked chemical etching techniques. The process may be used to form a wide variety of structures in garnet material for application in magnetic domain devices and integrated optics components.
Inventors
- 👤 W Johnson
- 👤 J North
- 👤 R Wolfe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 08:16
CPC Classifications
H; H01; H01F; H01F41/00; H01F41/32; H01F41/34; C; C04; C04B; C04B41/00; C04B41/53; C04B41/5338; C04B41/5353; C09; C09K; C09K13/00; C09K13/04; C30; C30B; C30B29/00; C30B29/10; C30B29/16; C30B29/22; C30B29/28; C30B33/00; Y; Y10; Y10S; Y10S148/00; Y10S148/051; Y10S148/084; Y10S148/15
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
51 words
The method according to claim 1 wherein the dose of the ion beam is chosen so that the etching rate of the crystal at the depth of maximum damage concentration in the damaged region is at least two times greater than the etching rate of the crystal outside the damaged region.
Claim 2
Dependent Claim
51 words
The method according to claim 1 wherein the dose of the ion beam is chosen so that the etching rate of the crystal at the depth of maximum damage concentration iN the damaged region is at least five times greater than the etching rate of the crystal outside the damaged region.
Claim 3
Dependent Claim
13 words
The method according to claim 1 wherein the etching solution is H3 PO4.
Claim 4
Dependent Claim
13 words
The method according to claim 1 wherein the ion beam comprises neon ions.
Claim 5
Dependent Claim
18 words
The method according to claim 5 wherein the dose of the ion beam is at least 1014 ions/cm2.
Claim 6
Dependent Claim
13 words
The method according to claim 1 wherein the ion beam comprises helium ions.
Claim 7
Dependent Claim
20 words
The method according to claim 7 wherein the dose of the ion beam is at least 4 X 1015 ions/cm2.
Claim 8
Dependent Claim
13 words
The method according to claim 1 wherein the ion beam comprises hydrogen ions.
Claim 9
Dependent Claim
20 words
The method according to claim 9 wherein the dose of the ion beam is at least 4 X 1016 ions/cm2.
Claim 10
Dependent Claim
17 words
The method according to claim 1 wherein the crystal comprises: Y1 Gd1 Tm1 Fe4.2 Ga0.8 O12 .
Claim 11
Dependent Claim
14 words
The method according to claim 1 wherein the crystal comprises: Y3 Al5 O12 .
Claim 12
Dependent Claim
70 words
The method according to claim 1 further comprising the steps of irradiating the surface of the crystal with a second ion beam so as to form a region of damage confined to the area of the crystal beneath the etched area and applying an etching solution to the surface of the crystal which will etch the region of damage at a faster rate than the remaining area of the crystal.
Claim 13
Dependent Claim
52 words
The method according to claim 1 wherein the dose of the ion beam is chosen so that the etching rate of the crystal at the depth of maximum damage concentration in the damaged region is at least two hundred times greater than the etching rate of the crystal outside the damaged region.
References Cited (Backward Citations)
US2989385A
Cited
US3041226A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-04-29 | 1977-10-29 | 1978-04-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-04-29 | 1981-10-29 | 1982-04-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-04-29 | 1985-10-29 | 1986-04-30 | $7700.00 | Window Closed / Lapsed |