USH77H
Expired / Lapsed
US
⏱️ 0.0 years remaining
Low loss, single-mode planar waveguide
Assignee: United States Department of the Army
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Filing: 1983-04-01
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Granted: 1986-07-01
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Expires: 2003-04-01
Abstract
Abstract A low loss optical waveguide is provided by taking a silicon substrate with a silicon dioxide waveguide thereon and depositing lead on the air interface surface of the silicon dioxide. The lead is then oxidized and diffused into the silicon dioxide creating a high optical quality, high index region at the air interface of the waveguide. This allows transmitted waveguide light energy directed into the silicon dioxide to be transmitted in the lead oxide diffused portion of the waveguide, keeping the energy away from the lossy silicon substrate, and thereby providing a low loss planar waveguide.
Inventors
- 👤 Shi-Kay Yao
- 👤 Joseph W. Niesen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 15:55
CPC Classifications
G; G02; G02B; G02B6/00; G02B6/10; G02B6/12; G02B6/13; G02B6/132
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
85 words
A method of making a single-mode planar waveguide comprising the steps of: depositing a layer of high index refractive material as a substrate, thermally oxidizing a layer of silicon dioxide onto a surface of said substrate for providing a single-mode waveguide thereon, depositing a layer of lead on to the exposed surface of said silicon dioxide waveguide, oxidizing said lead, and uniformly diffusing all of said oxidized lead a predetermined distance into said silicon dioxide waveguide less than two-fifths of the thickness of the waveguide.
Claim 2
Independent Claim
85 words
A method of making a single-mode planar waveguide comprising the steps of: depositing a layer of high index refractive material as a substrate, thermally oxidizing a layer of silicon dioxide onto a surface of said substrate for providing a single-mode waveguide thereon, depositing a layer of lead on to the exposed surface of said silicon dioxide waveguide, oxidizing said lead, and uniformly diffusing all of said oxidized lead a predetermined distance into said silicon dioxide waveguide less than two-fifths of the thickness of the waveguide.
Claim 3
Dependent Claim
57 words
A method of making a single-mode planar waveguide as set forth in claim 1 and further comprising the step of: depositing said layer of lead by evaporating a layer of lead 300 angstroms thick across the surface of said silicon dioxide layer, and oxidizing said lead by room air oxidation for 33 hours at 300 degrees centigrade.
Claim 4
Dependent Claim
34 words
A method of making a single-mode planar waveguide as set forth in claim 2 wherein the step of thermally oxidizing produces a selectable layer that is from 4 microns thick to 10 microns thick.
Claim 5
Dependent Claim
35 words
A method of making a single-mode planar waveguide as set forth in claim 3 wherein the step of diffusing produces a diffused region of a depth of only one micron into said silicon dioxide waveguide.
Claim 6
Dependent Claim
52 words
A method of making a single-mode planar waveguide as set forth in claim 3 wherein the step of diffusing said oxidized lead leaves at least a minimum separation of 3 microns between the inner surface of the silicon dioxide adjoining the substrate surface and the inner surface of the diffused oxidized lead.
Claim 7
Dependent Claim
40 words
A method of making a single-mode planar waveguide as set forth in claim 2 wherein the step of diffusing is carried out by subjecting said oxidized lead to an argon environment for at least 16 hours at 500 degrees centigrade.
Claim 8
Dependent Claim
90 words
A planar waveguide comprising: a high refractive index silicon substrate material; a thermally oxidized silicon layer of waveguide forming an isolation layer, said layer having first and second surfaces, and said first surface being disposed on the silicon substrate material; said oxidized silicon layer having a substantially uniform thickness of at least 4 microns; and a lead oxide region diffused into the second surface of the oxidized silicon layer, said diffused region having a substantially uniform thickness at least 3 microns less than the thickness of the oxidized silicon layer.
Claim 9
Dependent Claim
90 words
A planar waveguide comprising: a high refractive index silicon substrate material; a thermally oxidized silicon layer of waveguide forming an isolation layer, said layer having first and second surfaces, and said first surface being disposed on the silicon substrate material; said oxidized silicon layer having a substantially uniform thickness of at least 4 microns; and a lead oxide region diffused into the second surface of the oxidized silicon layer, said diffused region having a substantially uniform thickness at least 3 microns less than the thickness of the oxidized silicon layer.
Claim 10
Dependent Claim
24 words
A planar waveguide as set forth in claim 7 wherein said diffused region has a substantially uniform thickness of from 1 to 2 microns.
Claim 11
Dependent Claim
34 words
A planar waveguide as set forth in claim 8 wherein said oxidized silicon layer is not more than 10 microns thick and said diffused lead oxide region is not more than 2 microns thick.
Claim 12
Independent Claim
124 words
A method of making a single-mode planar waveguide comprising the steps of: depositing a layer of high index refractive material as a substrate, thermally oxidizing a layer of silicon dioxide onto a surface of said substrate for providing a single-mode waveguide thereon, depositing a layer of lead 300 angstrons thick across the exposed surface of said silicon dioxide layer, oxidizing said lead by room air oxidation for 33 hours at 300 degrees centigrade, subjecting the oxidized lead to a flowing argon environment for 16 hours at 500 degrees centigrade and for 151/2 hours at 800 degrees centigrade and thereby producing a uniformly diffused region of oxidized lead a predetermined distance into said silicon dioxide waveguide less than two-fifths of the thickness of the waveguide.
Claim 13
Independent Claim
124 words
A method of making a single-mode planar waveguide comprising the steps of: depositing a layer of high index refractive material as a substrate, thermally oxidizing a layer of silicon dioxide onto a surface of said substrate for providing a single-mode waveguide thereon, depositing a layer of lead 300 angstrons thick across the exposed surface of said silicon dioxide layer, oxidizing said lead by room air oxidation for 33 hours at 300 degrees centigrade, subjecting the oxidized lead to a flowing argon environment for 16 hours at 500 degrees centigrade and for 151/2 hours at 800 degrees centigrade and thereby producing a uniformly diffused region of oxidized lead a predetermined distance into said silicon dioxide waveguide less than two-fifths of the thickness of the waveguide.
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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) | 1989-06-30 | 1989-12-30 | 1990-07-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-06-30 | 1993-12-30 | 1994-07-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-06-30 | 1997-12-30 | 1998-07-01 | $7700.00 | Window Closed / Lapsed |