US5912477A
Expired / Lapsed
US
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High efficiency light emitting diodes
Assignee: Wolfspeed Inc
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Filing: 1997-05-20
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Granted: 1999-06-15
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Expires: 2017-05-20
Abstract
Abstract Light emitting diodes are disclosed which have increased external efficiency and are formed from silicon carbide substrates. Diodes are produced by a method which includes directing a beam of laser light at one surface of a portion of silicon carbide, and which the laser light is sufficient to vaporize the silicon carbide that it strikes to thereby define a cut in the silicon carbide portion; and then dry etching the silicon carbide portion to remove by-products generated when the laser light cuts the silicon carbide portion. The resulting diode structure includes reticulate patterned sidewalls that promote increased light emission efficiency.
Inventors
- 👤 Gerald H. Negley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 07:23
CPC Classifications
H; H10; H10H; H10H20/00; H10H20/80; H10H20/81; H10H20/822; H10H20/824; H10H20/825; B; B23; B23K; B23K26/00; B23K26/16; B23K26/36; B23K26/40; H10H20/01; H10H20/011; H10H20/013; H10H20/0133; H10H20/01335; H10H20/014; H10H20/826; H10P; H10P50/00; B23K2101/00; B23K2101/36; B23K2101/40; B23K2103/00; B23K2103/50; B23K2103/52; Y; Y10; Y10S; Y10S438/00; Y10S438/94
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
92 words
A high efficiency light emitting diode comprising: a silicon carbide substrate that includes reticulate patterned sidewalls; at least two epitaxial layers on said substrate that form a p-n junction therebetween, said epitaxial layers having reticulate patterned side edges and with the reticulate patterned side edges of said epitaxial layers being coincident with said reticulate patterned sidewalls of said substrate; and ohmic contacts for applying a potential across said junction; characterized in that said p-n junction produces an emission in the blue region of the visible spectrum when a potential is applied thereacross.
Claim 2
Dependent Claim
92 words
A high efficiency light emitting diode comprising: a silicon carbide substrate that includes reticulate patterned sidewalls; at least two epitaxial layers on said substrate that form a p-n junction therebetween, said epitaxial layers having reticulate patterned side edges and with the reticulate patterned side edges of said epitaxial layers being coincident with said reticulate patterned sidewalls of said substrate; and ohmic contacts for applying a potential across said junction; characterized in that said p-n junction produces an emission in the blue region of the visible spectrum when a potential is applied thereacross.
Claim 3
Dependent Claim
24 words
A light emitting diode according to claim 1 characterized in that the junction produces an emission of between about 450 and 490 nanometers (nm).
Claim 4
Dependent Claim
15 words
A light emitting diode according to claim 1 wherein said epitaxial layers comprise silicon carbide.
Claim 5
Dependent Claim
15 words
A light emitting diode according to claim 1 wherein said epitaxial layers comprise gallium nitride.
Claim 6
Dependent Claim
59 words
A high efficiency light emitting diode comprising: a silicon carbide substrate that includes reticulate patterned sidewalls; at least two epitaxial layers on said substrate that form a p-n junction therebetween; said epitaxial layers having reticulate patterned side edges that are coincident with said reticulate patterned sidewalls of said substrate; and ohmic contacts for applying a potential across said junction.
Claim 7
Dependent Claim
59 words
A high efficiency light emitting diode comprising: a silicon carbide substrate that includes reticulate patterned sidewalls; at least two epitaxial layers on said substrate that form a p-n junction therebetween; said epitaxial layers having reticulate patterned side edges that are coincident with said reticulate patterned sidewalls of said substrate; and ohmic contacts for applying a potential across said junction.
Claim 8
Dependent Claim
15 words
A light emitting diode according to claim 5 wherein said epitaxial layers comprise silicon carbide.
Claim 9
Dependent Claim
15 words
A light emitting diode according to claim 5 wherein said epitaxial layers comprise gallium nitride.
Claim 10
Dependent Claim
23 words
A light emitting diode according to claim 7 characterized in that the junction produces an emission of between about 350 and 550 nanometers.
Claim 11
Dependent Claim
31 words
A light emitting diode according to claim 5 characterized in that said p-n junction produces an emission in the blue region of the visible spectrum when a potential is applied thereacross.
Claim 12
Dependent Claim
23 words
A light emitting diode according to claim 9 characterized in that the junction produces an emission of between about 450 and 490 nanometers.
Claim 13
Dependent Claim
31 words
A light emitting diode according to claim 5 characterized in that said p-n junction produces an emission in the green region of the visible spectrum when a potential is applied thereacross.
Claim 14
Dependent Claim
23 words
A light emitting diode according to claim 11 characterized in that the junction produces an emission of between about 520 and 540 nanometers.
Claim 15
Dependent Claim
92 words
A high efficiency light emitting diode comprising: a silicon carbide substrate that includes reticulate patterned sidewalls; at least two epitaxial layers on said substrate that form a p-n junction therebetween, said epitaxial layers having reticulate patterned side edges and with the reticulate patterned side edges of said epitaxial layers being coincident with said reticulate patterned sidewalls of said substrate; and ohmic contacts for applying a potential across said junction; characterized in that said p-n junction produces an emission in the green region of the visible spectrum when a potential is applied thereacross.
Claim 16
Dependent Claim
92 words
A high efficiency light emitting diode comprising: a silicon carbide substrate that includes reticulate patterned sidewalls; at least two epitaxial layers on said substrate that form a p-n junction therebetween, said epitaxial layers having reticulate patterned side edges and with the reticulate patterned side edges of said epitaxial layers being coincident with said reticulate patterned sidewalls of said substrate; and ohmic contacts for applying a potential across said junction; characterized in that said p-n junction produces an emission in the green region of the visible spectrum when a potential is applied thereacross.
Claim 17
Dependent Claim
23 words
A light emitting diode according to claim 13 characterized in that the junction produces an emission of between about 520 and 540 nanometers.
Claim 18
Dependent Claim
15 words
A light emitting diode according to claim 13 wherein said epitaxial layers comprise silicon carbide.
Claim 19
Dependent Claim
15 words
A light emitting diode according to claim 13 wherein said epitaxial layers comprise gallium nitride.
Claim 20
Dependent Claim
23 words
A light emitting diode according to claim 16 characterized in that the junction produces an emission of between about 350 and 550 nanometers.
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 2002-06-14 | 2002-12-14 | 2003-06-15 | $2000.00 | Window Closed / Lapsed |
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