US5147825A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Photonic-integrated-circuit fabrication process
Assignee: AT&T Inc
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Filing: 1988-08-26
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Granted: 1992-09-15
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Expires: 2008-08-26
Abstract
Abstract An improved process for fabricating photonic circuits is disclosed. The inventive process starts with a growth of a base wafer comprising a stack of epitaxial layers of various materials. At least a portion of each of the material layers will ultimately be a functioning part of any of a number of devices which will form the PIC or will serve a role in at least one of the fabrication processing steps. Specific inventive processing steps are addressed to (1) interconnecting passive waveguides, active devices, and grating filtering regions without the substantial optical discontinuities which appear in the prior art, and (2) etching continuous waveguide mesas to different depths in different regions of the PIC so as to optimize the performance of each PIC device.
Inventors
- 👤 Thomas L. Koch
- 👤 Uziel Koren
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 10:28
CPC Classifications
H; H01; H01S; H01S5/00; H01S5/02; H01S5/026; H01S5/0262; H01S5/0264; G; G02; G02B; G02B6/00; G02B6/10; G02B6/12; G02B6/122; G02B6/124; G02B6/13; G02B6/136; H10; H10D; H10D84/00; H10D84/01; H10D84/02; H10D84/05; H01S5/10; H01S5/12; H01S5/1231; Y; Y10; Y10S; Y10S148/00; Y10S148/095; Y10S148/106; Y10S438/00; Y10S438/942
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
112 words
A method of etching a first, patterned surface adjacent to a second surface, which second surface remains substantially unetched during the etching, comprising forming a second-surface-masking-material over the second surface, forming a corrugated mask over both the first surface and the second-surface-masking-material to form first and second masked surfaces, respectively, and exposing both the first and second masked surfaces to an etchant, THE INVENTION CHARACTERIZED IN THAT: the said first and second masked surfaces etch at substantially the same rate when exposed to the said etchant, whereby the said first surface is uniformly patterned without any substantial discontinuity in the pattern in regions of the first surface adjacent to the second surface.
Claim 2
Independent Claim
112 words
A method of etching a first, patterned surface adjacent to a second surface, which second surface remains substantially unetched during the etching, comprising forming a second-surface-masking-material over the second surface, forming a corrugated mask over both the first surface and the second-surface-masking-material to form first and second masked surfaces, respectively, and exposing both the first and second masked surfaces to an etchant, THE INVENTION CHARACTERIZED IN THAT: the said first and second masked surfaces etch at substantially the same rate when exposed to the said etchant, whereby the said first surface is uniformly patterned without any substantial discontinuity in the pattern in regions of the first surface adjacent to the second surface.
Claim 3
Dependent Claim
11 words
The method of claim 1 wherein the surfaces are semiconductor materials.
Claim 4
Dependent Claim
19 words
The method of claim 2 wherein said semiconductor materials are selected from the group consisting of III-V compound semiconductors.
Claim 5
Dependent Claim
11 words
The method of claim 3 wherein the semiconductor material comprises InGaAsP.
Claim 6
Dependent Claim
16 words
The method of claim 1 wherein the second surface masking material is an epitaxially grown material.
Claim 7
Dependent Claim
13 words
The method of claim 5 wherein the epitaxially grown material is a semiconductor.
Claim 8
Dependent Claim
22 words
The method of claim 1 wherein the said first and second surfaces comprise InGaAsP and the second surface masking material comprises InP.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-09-15 | 1996-03-16 | 1996-09-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-09-15 | 2000-03-16 | 2000-09-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-09-15 | 2004-03-16 | 2004-09-15 | $7700.00 | Window Closed / Lapsed |