Patent US5720893A successfully refreshed from Google Patents.
US5720893A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Tapered beam expander waveguide integrated with a diode lasesr
Assignee: Nokia of America Corp
•
Filing: 1996-05-01
•
Granted: 1998-02-24
•
Expires: 2016-05-01
Abstract
Abstract The present invention is directed to a semiconductor waveguiding structure which includes a) a first semiconductor waveguiding layer formed on a substrate, b) a barrier layer that is formed on the first semiconductor waveguiding layer, and that is resistant to a selected etchant, and c) a second semiconductor waveguiding layer that is etched using the selected etchant such that its width is tapered along its length to a pointed edge. A separate etching of the first semiconductor layer is performed to form each sidewall of the first semiconductor layer. The intersection of those sidewalls defines the pointed edge which has a radius of curvature of less than 500 Angstroms.
Inventors
- 👤 Rafael Ben-Michael
- 👤 Uziel Koren
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 15:06
CPC Classifications
G; G02; G02B; G02B6/00; G02B6/10; G02B6/12; G02B6/122; G02B6/1228; H; H01; H01S; H01S5/00; H01S5/02; H01S5/026; H01S5/10; H01S5/1028; G02B2006/12083; G02B2006/12121; G02B2006/12166; G02B2006/12176; G02B2006/12195; G02B6/24; G02B6/26; G02B6/30; G02B6/305; H01S5/1003; H01S5/1014; H01S5/1032; H01S5/1053; H01S5/1064
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
154 words
In a semiconductor waveguiding structure which includes a) a first semiconductor waveguiding layer mounted on a substrate, b) an etch-resistant barrier layer formed on the first waveguiding layer, and c) a second semiconductor waveguiding layer formed on the barrier layer, a method of fabricating a tapered semiconductor waveguiding structure, the method comprising the steps of: depositing a first mask on a first portion of the second semiconductor waveguiding layer; etching a first section of the second semiconductor waveguiding layer unprotected by the first mask to create a first sidewall; removing the first mask; applying a second mask on part of the first portion and a second portion of the second semiconductor waveguiding layer such that an edge of the second mask intersects the first sidewall; etching a second section of the second semiconductor waveguiding layer unprotected by the second mask to define a second wall intersecting the first sidewall to form a pointed edge.
Claim 2
Dependent Claim
154 words
In a semiconductor waveguiding structure which includes a) a first semiconductor waveguiding layer mounted on a substrate, b) an etch-resistant barrier layer formed on the first waveguiding layer, and c) a second semiconductor waveguiding layer formed on the barrier layer, a method of fabricating a tapered semiconductor waveguiding structure, the method comprising the steps of: depositing a first mask on a first portion of the second semiconductor waveguiding layer; etching a first section of the second semiconductor waveguiding layer unprotected by the first mask to create a first sidewall; removing the first mask; applying a second mask on part of the first portion and a second portion of the second semiconductor waveguiding layer such that an edge of the second mask intersects the first sidewall; etching a second section of the second semiconductor waveguiding layer unprotected by the second mask to define a second wall intersecting the first sidewall to form a pointed edge.
Claim 3
Dependent Claim
25 words
The invention of claim 1 wherein, from a top view of the second semiconductor waveguiding layer, at least one of the sidewalls is slanted upwards.
Claim 4
Dependent Claim
25 words
The invention of claim 1 wherein, from a top view of the second semiconductor waveguiding layer, at least one of the sidewalls is slanted downwards.
Claim 5
Dependent Claim
32 words
The invention of claim 1 wherein, from a top view of the second semiconductor waveguiding layer, at least one of the sidewalls is slanted upwards and the other sidewall is slanted downwards.
Claim 6
Dependent Claim
14 words
The invention of claim 1 wherein at least one of the sidewalls is convex.
References Cited (Backward Citations)
JPS58114476A
Cited
US4932032A
Cited
US5121182A
Cited
US5078516A
Cited
JPH04180686A
Cited
US5260822A
Cited
US5434973A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2001-02-23 | 2001-08-25 | 2002-02-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-02-23 | 2005-08-25 | 2006-02-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-02-23 | 2009-08-25 | 2010-02-24 | $7700.00 | Window Closed / Lapsed |