US3930912A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of manufacturing light emitting diodes
Assignee: BAE Systems Electronics Ltd
•
Filing: 1974-09-16
•
Granted: 1976-01-06
•
Expires: 1994-09-16
Abstract
Abstract The invention relates to the manufacture of arrays of light emitting diodes (L.E.D.'s) from a wafer consisting of an n-type epitaxial layer on an n + substrate. The method includes the steps of forming p-type islands by diffusing a p-type dopant into the epitaxial layer of an n on n + wafer, establishing contact with all of the p-type islands by means of a first set of conductors, mounting the wafer on a transparent support with the first set of conductors adjacent the support, depositing a second set of conductors on the n + substrate and etching both the substrate and the epitaxial layer from between the conductors of the second set, the two sets of conductors being orthogonal and each p-n junction formed by a p-type island and the epitaxial layer being in contact with one and only one conductor from each set.
Inventors
- 👤 Philip Henry Wisbey
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 10:05
CPC Classifications
H; H10; H10H; H10H29/00; H10H29/10; H10H29/14; H10H29/142; Y; Y10; Y10S; Y10S148/00; Y10S148/02; Y10S148/051; Y10S148/085; Y10S148/15
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
202 words
A method of forming a plurality of light emitting diodes in an arrangement of columns and rows, said method comprising the steps of: providing an n-type epitaxial layer formed on an n +-type substrate; diffusing a p-type dopant into selected regions of said epitaxial n-type layer to form a plurality of p-type islands arranged in columns and rows, each p-type island having a junction with said n-type epitaxial layer to form a p-n diode of said arrangement; covering each row of said arrangement with a different one of a plurality of first conductors, each first conductor being electrically connected to all p-n diodes in its row and being electrically isolated from every other first conductor; mounting said arrangement on a transparent support with said plurality of first conductors adjacent thereto; covering said n + type substrate with a plurality of second conductors in orthogonal relation to said plurality of first conductors, each second conductor being aligned with a different one of said columns and said second conductors being spaced apart to form gaps therebetween which are registered with areas between p-type islands; and etching those portions of said n-type epitaxial layer and said n + type substrate which coincide with said gaps.
Claim 2
Independent Claim
202 words
A method of forming a plurality of light emitting diodes in an arrangement of columns and rows, said method comprising the steps of: providing an n-type epitaxial layer formed on an n +-type substrate; diffusing a p-type dopant into selected regions of said epitaxial n-type layer to form a plurality of p-type islands arranged in columns and rows, each p-type island having a junction with said n-type epitaxial layer to form a p-n diode of said arrangement; covering each row of said arrangement with a different one of a plurality of first conductors, each first conductor being electrically connected to all p-n diodes in its row and being electrically isolated from every other first conductor; mounting said arrangement on a transparent support with said plurality of first conductors adjacent thereto; covering said n + type substrate with a plurality of second conductors in orthogonal relation to said plurality of first conductors, each second conductor being aligned with a different one of said columns and said second conductors being spaced apart to form gaps therebetween which are registered with areas between p-type islands; and etching those portions of said n-type epitaxial layer and said n + type substrate which coincide with said gaps.
Claim 3
Dependent Claim
34 words
A method as recited in claim 1 in which said first conductors are arranged to cover the p-type islands and are provided with windows from which a portion of the islands may be viewed.
Claim 4
Dependent Claim
23 words
A method as recited in claim 1 in which said first set of conductors are plated up to provide a substantial metal conductor.
Claim 5
Dependent Claim
15 words
A method as recited in claim 3 wherein said metal conductor is formed of copper.
Claim 6
Dependent Claim
15 words
A method as recited in claim 1 wherein said transparent support is made of sapphire.
Claim 7
Dependent Claim
24 words
A method as recited in claim 1 wherein the thickness of said substrate is reduced prior to depositing said second set of conductors thereon.
References Cited (Backward Citations)
US3590479A
Cited
US3559283A
Cited
US3767494A
Cited
US3746587A
Cited
US3765970A
Cited
US3689993A
Cited
US3805376A
Cited
US3853650A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-01-05 | 1979-07-07 | 1980-01-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-01-05 | 1983-07-07 | 1984-01-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-01-05 | 1987-07-07 | 1988-01-06 | $7700.00 | Window Closed / Lapsed |