US4589116A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Laser diode with uniform mechanical stress and/or heat dissipation
Assignee: Siemens AG
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Filing: 1984-07-23
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Granted: 1986-05-13
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Expires: 2004-07-23
Abstract
Abstract For reduction and uniformity of mechanical stresses and for uniformity of current supply and heat dissipation into or out of a laser active zone of a laser diode, an additional layer preferably restricted to a waveguide region is provided between a contact layer and a solder layer mounting the diode on a heat sink.
Inventors
- 👤 Heinz Westermeier
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 16:03
CPC Classifications
H; H01; H01S; H01S5/00; H01S5/02
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
155 words
A laser diode, comprising: a semiconductor substrate in which a strip-shaped laser active zone is provided near its upside; the substrate being assembled in upside-down-technology on a heat sink with the laser active zone at a bottom side of the substrate and a metal contact layer being positioned between the heat sink and the substrate in a proximity of the laser-active zone; a solder layer between said metal contact layer and said heat sink with which the substrate and the heat sink are interconnected in fixed manner; between a portion of the contact layer and a portion of the solder layer an additional layer comprised of a material which substantially prevents alloy formation between the metal of the contact layer and the solder; and said additional layer extending over an entire length of the laser-active zone and having a width which corresponds at least to a width of a waveguide region of the laser-active zone.
Claim 2
Dependent Claim
155 words
A laser diode, comprising: a semiconductor substrate in which a strip-shaped laser active zone is provided near its upside; the substrate being assembled in upside-down-technology on a heat sink with the laser active zone at a bottom side of the substrate and a metal contact layer being positioned between the heat sink and the substrate in a proximity of the laser-active zone; a solder layer between said metal contact layer and said heat sink with which the substrate and the heat sink are interconnected in fixed manner; between a portion of the contact layer and a portion of the solder layer an additional layer comprised of a material which substantially prevents alloy formation between the metal of the contact layer and the solder; and said additional layer extending over an entire length of the laser-active zone and having a width which corresponds at least to a width of a waveguide region of the laser-active zone.
Claim 3
Dependent Claim
16 words
A laser diode according to claim 1 wherein the metal of the contact layer is gold.
Claim 4
Dependent Claim
33 words
A laser diode according to claim 1 wherein the material of the additional layer is a metal oxide with a relatively low electric conductivity compared to the contact layer, but good thermal conductivity.
Claim 5
Dependent Claim
17 words
A laser diode according to claim 3 wherein the material of the additional layer is aluminum oxide.
Claim 6
Dependent Claim
17 words
A laser diode according to claim 3 wherein the material of the additional layer is silicon oxide.
Claim 7
Dependent Claim
17 words
A laser diode according to claim 1 wherein the material of the additional layer is silicon nitride.
Claim 8
Dependent Claim
19 words
A laser diode according to claim 1 wherein the width of the additional layer is 10 to 70 μm.
Claim 9
Dependent Claim
24 words
A laser diode according to claim 1 wherein the width of the additional layer is substantially equal to the width of the waveguide region.
Claim 10
Dependent Claim
13 words
A laser diode according to claim 1 wherein the additional layer conprises molybdenum.
Claim 11
Dependent Claim
13 words
A laser diode according to claim 1 wherein the additional layer comprises tungsten.
Claim 12
Dependent Claim
125 words
A laser diode, comprising: a semiconductor substrate with upper and lower surfaces; the upper surface having a substrate contact and the lower surface joining with at least first and second layers; a strip-shaped laser active zone adjacent the lower surface of the substrate; a metal contact layer in contact with the most outside of said layers; a heat sink; a solder layer connecting the contact layer to the heat sink; and an additional layer comprised of a material which substantially prevents alloy formation between metal of the contact layer and the solder; and said additional layer extending over substantially an entire length of the laser-active zone and having a width which corresponds at least to a width of a waveguide region of the laser-active zone.
Claim 13
Dependent Claim
125 words
A laser diode, comprising: a semiconductor substrate with upper and lower surfaces; the upper surface having a substrate contact and the lower surface joining with at least first and second layers; a strip-shaped laser active zone adjacent the lower surface of the substrate; a metal contact layer in contact with the most outside of said layers; a heat sink; a solder layer connecting the contact layer to the heat sink; and an additional layer comprised of a material which substantially prevents alloy formation between metal of the contact layer and the solder; and said additional layer extending over substantially an entire length of the laser-active zone and having a width which corresponds at least to a width of a waveguide region of the laser-active zone.
Claim 14
Dependent Claim
19 words
A laser diode according to claim 11 wherein the width of the additional layer is 10 to 70 μm.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-05-12 | 1989-11-11 | 1990-05-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-05-12 | 1993-11-11 | 1994-05-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-05-12 | 1997-11-11 | 1998-05-13 | $7700.00 | Window Closed / Lapsed |