US5035916A
Expired / Lapsed
US
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Optical waveguide and method for its manufacture
Assignee: Nortel Networks UK Ltd
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Filing: 1990-03-28
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Granted: 1991-07-30
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Expires: 2010-03-28
Abstract
Abstract An optical waveguide is made by forming a layer of SiO 2 on a substrate and implanting a region of the SiO 2 layer with Si ions to define a region containing a stoichiometric excess of Si which defines a region having an elevated refractive index surrounded by a region having a lower refractive index. The resulting optical waveguide is stable at the high temperatures required for many semiconductor processing methods, and is useful for optical interconnection in integrated optical and optoelectronic devices.
Inventors
- 👤 Alexander Kalnitsky
- 👤 Joseph P. Ellul
- 👤 Albert R. Boothroyd
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 19:08
CPC Classifications
G; G02; G02B; G02B6/00; G02B6/10; G02B6/12; G02B6/13; G02B6/134; G02B6/1347
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
96 words
A method for making a planar optical waveguide, the method comprising: forming a layer of Si0 2 on a substrate; forming an ion implantation mask over the Si0 2 layer, the ion implantation mask having openings therethrough over regions of the Si0 2 layer where an optical waveguide channel is desired; and selectively implanting a region of the Si0 2 layer with Si ions through the openings of the ion implantation mask to define a planar optical waveguide comprising a channel region having an elevated refractive index surrounded by a region having a lower refractive index.
Claim 2
Independent Claim
96 words
A method for making a planar optical waveguide, the method comprising: forming a layer of Si0 2 on a substrate; forming an ion implantation mask over the Si0 2 layer, the ion implantation mask having openings therethrough over regions of the Si0 2 layer where an optical waveguide channel is desired; and selectively implanting a region of the Si0 2 layer with Si ions through the openings of the ion implantation mask to define a planar optical waveguide comprising a channel region having an elevated refractive index surrounded by a region having a lower refractive index.
Claim 3
Dependent Claim
31 words
A method as defined in claim 1, wherein the step of forming a layer of Si0 2 on a substrate comprises growing a layer of Si0 2 on a Si substrate.
Claim 4
Dependent Claim
35 words
A method as defined in claim 2, wherein the step of growing a layer of Si0 2 on a Si substrate comprises growing a layer of Si0 2 on the Si substrate by steam oxidation.
Claim 5
Dependent Claim
19 words
A method as defined in claim 3, wherein the steam oxidation is performed at a pressure exceeding atmospheric pressure.
Claim 6
Dependent Claim
34 words
A method as defined in claim 1, wherein the step of forming a layer of Si0 2 on a substrate comprises depositing a layer of Si0 2 on a substrate by chemical vapour deposition.
Claim 7
Dependent Claim
52 words
A method as defined in claim 1, wherein the step of implanting a region of the Si0 2 layer with Si ions comprises implanting the Si ions with an implantation dose between 1×10 14 cm -2 and 2×10 17 cm -2 and with an implantation energy between 3 keV and 400 keV.
Claim 8
Independent Claim
104 words
A method for making a planar optical waveguide, the method comprising: forming a layer of Si0 2 on a substrate; implanting the Si0 2 layer with Si ions to define a region having an elevated refractive index; forming an oxidation-resistant mask over the regions of the implanted Si0 2 layer where an optical waveguide channel is desired; and heating the Si0 2 layer in an oxidizing ambient to oxidize the implanted Si in exposed regions of the Si0 2 layer to define a planar optical waveguide comprising a channel region having an elevated refractive index surrounded by a region having a lower refractive index.
Claim 9
Independent Claim
104 words
A method for making a planar optical waveguide, the method comprising: forming a layer of Si0 2 on a substrate; implanting the Si0 2 layer with Si ions to define a region having an elevated refractive index; forming an oxidation-resistant mask over the regions of the implanted Si0 2 layer where an optical waveguide channel is desired; and heating the Si0 2 layer in an oxidizing ambient to oxidize the implanted Si in exposed regions of the Si0 2 layer to define a planar optical waveguide comprising a channel region having an elevated refractive index surrounded by a region having a lower refractive index.
Claim 10
Dependent Claim
26 words
A method as defined in claim 1, further comprising annealing the implanted Si0 2 layer at a temperature exceeding 1000 degrees Celsius in a non-oxidizing ambient.
Claim 11
Dependent Claim
25 words
A method as defined in claim 1, comprising performing a series of implantation steps at different implantation energies to define a non-Gaussian refractive index profile.
Claim 12
Dependent Claim
17 words
A method as defined in claim 9, wherein successive implantation steps are performed with different implantation doses.
Claim 13
Dependent Claim
17 words
A method as defined in claim 10, wherein successive implantation steps are performed through different implantation masks.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1994-07-29 | 1995-01-28 | 1995-07-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-07-29 | 1999-01-28 | 1999-07-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-07-29 | 2003-01-28 | 2003-07-30 | $7700.00 | Window Closed / Lapsed |