US4670093A
Expired / Lapsed
US
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Method for manufacturing a surface grating of a defined grating constant on regions of a mesa structure
Assignee: Siemens AG
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Filing: 1986-04-21
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Granted: 1987-06-02
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Expires: 2006-04-21
Abstract
Abstract A method for manufacturing a surface grating on a mesa structure of a laser includes etching a substrate surface by wet-chemical etching to form a surface grating of defined grating constant, masking regions of the surface grating corresponding to the mesa structure, and further etching the unmasked regions to transfer the surface grating to the more deeply situated surface regions of the mesa structure while retaining substantially the same grating constant.
Inventors
- 👤 Reinhard Maerz
- 👤 Gerhard Heise
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 03:51
CPC Classifications
H; H10; H10H; H10H20/00; H10H20/80; H10H20/81; H10H20/817; G; G02; G02B; G02B5/00; G02B5/18; G02B5/1814; G02B5/1847; G02B5/1857; H01; H01S; H01S5/00; H01S5/10; H01S5/12; H10H20/01; H10P; H10P50/00; H10P50/60; H10P50/64; H10P50/642; H10P50/646; H10P50/648; H10P50/69; H10P50/691; H10P50/693; H01S5/1237; H01S5/20; H01S5/22; H10H20/819
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
98 words
A method for manufacturing a surface grating of a defined grating constant on a stepped structure, comprising the steps of: (a) etching a crystalline substrate surface with a surface grating of a defined surface constant by a wet-chemical anisotropic etchant, said etching proceeding more slowly in at least one direction oblique to said substrate surface; (b) masking a region of said surface grating to define unmasked regions; and (c) further etching said unmasked regions by an anisotropic etchant to produce more deeply situated regions of said stepped structure, said more deeply situated regions retaining said defined grating constant.
Claim 2
Independent Claim
98 words
A method for manufacturing a surface grating of a defined grating constant on a stepped structure, comprising the steps of: (a) etching a crystalline substrate surface with a surface grating of a defined surface constant by a wet-chemical anisotropic etchant, said etching proceeding more slowly in at least one direction oblique to said substrate surface; (b) masking a region of said surface grating to define unmasked regions; and (c) further etching said unmasked regions by an anisotropic etchant to produce more deeply situated regions of said stepped structure, said more deeply situated regions retaining said defined grating constant.
Claim 3
Dependent Claim
13 words
A method as claimed in claim 1, wherein a mesa structure is formed.
Claim 4
Dependent Claim
21 words
A method as claimed in claim 1, wherein substantially the same anisotropic etchant is used in both steps a and c.
Claim 5
Dependent Claim
17 words
A method as claimed in claim 1, wherein a distributed feedback-metal cladded ridge waveguide laser is formed.
Claim 6
Dependent Claim
29 words
A method as claimed in claim 1, wherein the substrate is composed of InP and the etchant is a mixture composed of HBr, saturated Brom water (SBW) and water.
Claim 7
Dependent Claim
33 words
A method as claimed in claim 1, wherein the substrate is composed of GaAs and the etchant is a mixture composed of H 2 SO 4 , H 2 O 2 and water.
References Cited (Backward Citations)
US4405405A
Cited
DE3437209A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-06-01 | 1990-12-01 | 1991-06-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-06-01 | 1994-12-01 | 1995-06-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-06-01 | 1998-12-01 | 1999-06-02 | $7700.00 | Window Closed / Lapsed |