US4028146A
Expired / Lapsed
US
⏱️ 0.0 years remaining
LPE Technique for fabricating tapered optical couplers
Assignee: AT&T Inc
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Filing: 1976-05-20
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Granted: 1977-06-07
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Expires: 1996-05-20
Abstract
Abstract Described is a double heterostructure junction laser in which the active region tapers to zero thickness within the structure, causing light to couple into an adjacent, underlying passive waveguide layer. Also described is a laser device in which the passive waveguide layer terminates in a region of increased thickness adjacent a laser output face. In addition, LPE and MBE techniques for fabricating the tapers are described.
Inventors
- 👤 Ralph Andre Logan
- 👤 James Logan Merz
- 👤 Franz Karl Reinhart
- 👤 Harry Gregory White
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 04:05
CPC Classifications
G; G02; G02B; G02B6/00; G02B6/24; G02B6/42; H; H01; H01S; H01S5/00; H01S5/02; H01S5/026; H01S5/0265; H01S5/10; H01S5/1028; H01S5/1032; H01S5/16; H01S5/164; H10; H10H; H10H20/00; H10H20/01; H10H20/011; H10H20/013; H10P; H10P14/00; H10P14/20; H10P14/26; H10P14/263; H10P14/265; H10P14/27; H10P14/271; H10P14/272; H10P14/29; H10P14/2901; H10P14/2907; H10P14/2911; H10P14/32; H10P14/3202; H10P14/3214; H10P14/3221; H10P14/34; H10P14/3402; H10P14/3414; H10P14/3421; Y; Y10; Y10S; Y10S117/00; Y10S117/918
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
77 words
A liquid phase epitaxy method of fabricating on a substrate a layer having a taper adjacent a zone of uniform thickness comprising the steps of: positioning a mask in closely spaced relation over a portion of said substrate, bringing a saturated source solution into contact with said substrate while maintaining a controlled cooling program for a time period effective to grow said layer to the desired thickness, said taper being formed adjacent the edges of said mask.
Claim 2
Dependent Claim
77 words
A liquid phase epitaxy method of fabricating on a substrate a layer having a taper adjacent a zone of uniform thickness comprising the steps of: positioning a mask in closely spaced relation over a portion of said substrate, bringing a saturated source solution into contact with said substrate while maintaining a controlled cooling program for a time period effective to grow said layer to the desired thickness, said taper being formed adjacent the edges of said mask.
Claim 3
Dependent Claim
16 words
The method of claim 1 wherein said source solutions comprise Ga and said mask comprises sapphire.
Claim 4
Dependent Claim
14 words
The method of claim 2 wherein said saturated source solution comprises Ga and As.
Claim 5
Dependent Claim
38 words
The method of claim 3 wherein said solution is composed of constituents effective to grow said layer comprising a compound of the form Al x Ga 1 -x R, X ≧ O and R includes at least As.
Claim 6
Dependent Claim
27 words
The method of claim 4 wherein R includes P also, said layer comprising Al x Ga 1 -x As 1 -y P y , y > O.
Claim 7
Dependent Claim
62 words
The method of claim 1 including the additional steps of: immediately prior to growing said tapered layer, growing a first layer having a wider bandgap than said tapered layer, said mask then being positioned in closely spaced relation to said first layer; and immediately subsequent to growing said tapered layer, growing a second layer having a wider bandgap than said tapered layer.
Claim 8
Dependent Claim
58 words
The method of claim 1 including the additional steps of: immediately prior to growing said tapered layer, growing a first layer having a wider bandgap than said tapered layer, said mask then being positioned in closely spaced relation to said first layer, and performing processing operations on the portion of said first layer which was under said mask.
Claim 9
Dependent Claim
164 words
A liquid phase epitaxy method of fabricating a layer having a taper adjacent a zone of uniform thickness, said method being carried out in an apparatus which includes a source solution holder having at least one well for carrying a source solution and a substrate holder having a recess for carrying a substrate, said solution and substrate holders being movable relative to one another in order to bring said solution and said substrate into contact with one another, said apparatus being placed in a furnace, heated to an elevated temperature to saturate solutions in said at least one well, and a controlled cooling program instituted to effect growth, CHARACTERIZED IN THAT, said at least one well includes a thin, flat mask positioned at the bottom of said at least one well in closely spaced relation to said substrate, said mask being effective to shield the portion of said substrate thereunder from said source solution, said taper being formed at the edge of said mask.
Claim 10
Dependent Claim
164 words
A liquid phase epitaxy method of fabricating a layer having a taper adjacent a zone of uniform thickness, said method being carried out in an apparatus which includes a source solution holder having at least one well for carrying a source solution and a substrate holder having a recess for carrying a substrate, said solution and substrate holders being movable relative to one another in order to bring said solution and said substrate into contact with one another, said apparatus being placed in a furnace, heated to an elevated temperature to saturate solutions in said at least one well, and a controlled cooling program instituted to effect growth, CHARACTERIZED IN THAT, said at least one well includes a thin, flat mask positioned at the bottom of said at least one well in closely spaced relation to said substrate, said mask being effective to shield the portion of said substrate thereunder from said source solution, said taper being formed at the edge of said mask.
Claim 11
Dependent Claim
55 words
The method of claim 8 wherein said apparatus includes a removable hollow module which fits snuggly into said at least one well, said module being opened at its bottom and top to permit said solution to be placed therein and to contact said substrate, said mask being affixed across the open bottom of said module.
Claim 12
Dependent Claim
16 words
The method of claim 9 wherein said source solution comprises Ga and said mask comprises sapphire.
Claim 13
Dependent Claim
38 words
The method of claim 9 wherein said solution is composed of constituents effective to grow said layer comprising a compound of the form Al x Ga 1 -x R, X ≧ O, and R includes at least As.
References Cited (Backward Citations)
US3428845A
Cited
US3615931A
Cited
US3883888A
Cited
US3962716A
Cited
US3993963A
Cited
US3948583A
Cited
US3978426A
Cited
US3978428A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-06-06 | 1980-12-06 | 1981-06-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-06-06 | 1984-12-06 | 1985-06-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-06-06 | 1988-12-06 | 1989-06-07 | $7700.00 | Window Closed / Lapsed |