MULTIPLE COLOR LIGHT EMITTING DIODES

• US 3,611,069 A
• Filed: 11/12/1969
• Issued: 10/05/1971
• Est. Priority Date: 11/12/1969
• Status: Expired due to Term

• Current Assignee: Gunther E. Fenner, Rogers S. Ehle, Simeon V. Galginaitis
• Original Assignee: Gunther E. Fenner, Rogers S. Ehle, Simeon V. Galginaitis
• Inventors: Galginaitis, Simeon V., Fenner, Gunther E., Ehle, Rogers S.
• Primary Examiner(s): Huckert, John W.
• Assistant Examiner(s): Edlow, Martin H.
• Application Number:
  US04/875,917
• Time in Patent Office: 692 Days
• Field of Search: 317/235 (27)/ 317/235 (42)/ 317/235N,235R,235W 250/211J,83,217SS,235
• US Class Current: 257/90
• CPC Class Codes: H01L 21/02392 Phosphides
• CPC Class Codes: H01L 21/02461 Phosphides
• CPC Class Codes: H01L 21/02543 Phosphides
• CPC Class Codes: H01L 21/02625 using melted materials
• CPC Class Codes: H01L 21/02628 using solutions
• CPC Class Codes: H01L 33/00 Semiconductor devices having potential barriers specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof H10K50/00 takes precedence; devices consisting of a plurality of semiconductor components formed in or on a common substrate and including semiconductor components having potential barriers, specially adapted for light emission H01L27/15; semiconductor lasers H01S5/00
• CPC Class Codes: H01L 33/0016 having at least two p-n junctions
• CPC Class Codes: H01L 33/0062 for devices with an active region comprising only III-V compounds
• CPC Class Codes: H01L 33/30 containing only elements of Group III and Group V of the Periodic Table
• CPC Class Codes: Y10S 148/043 Dual dielectric
• CPC Class Codes: Y10S 148/049 Equivalence and options
• CPC Class Codes: Y10S 148/065 Gp III-V generic compounds-processing
• CPC Class Codes: Y10S 148/067 Graded energy gap
• CPC Class Codes: Y10S 148/099 LED, multicolor
• CPC Class Codes: Y10S 148/107 Melt
• CPC Class Codes: Y10S 148/119 Phosphides of gallium or indium
• CPC Class Codes: Y10S 438/956 Making multiple wavelength emissive device

Abstract

Multiple color light-emitting semiconductor structures and methods for fabricating them are disclosed. The light-emitting structures comprise multiple-layered regions of differing conductivity-type semiconductor materials such as compositions of gallium phosphide which are made to emit light of selectively different wavelengths. The characteristics of the light-emitting structures are enhanced by lowering the optical absorption of high-energy photons by the use of a material with an increased band-gap.

Claims

2. The multiple color light-emitting structure of claim 1 wherein said third layer has a surface which interfaces with the medium of transmission and light emission from said first and second light-emitting junctions passes therethrough.

3. The multiple color light-emitting structure of claim 1 wherein said light-emitting junctions are of substantially the same area and in axial alignment with each other.

4. The multiple color light-emitting structure of claim 1 wherein said first light-emitting junction has an emission of a lower photon energy than said second light-emitting junction.

5. A multiple color light-emitting structure comprising:

a first layer of one conductivity-type gallium phosphide;

a second layer of an opposite conductivity-type gallium phosphide overlying said first layer and forming therewith a first light-emitting junction at the interface;

a third layer of said opposite conductivity-type gallium phosphide overlying said second layer; and

a fourth layer of said one conductivity-type gallium phosphide overlying said third layer and forming therewith a second light-emitting junction, said third and/or said fourth layers having a higher band gap than said first and second layers for reducing absorption of light passing therethrough wherein said higher band gap layers include compositions of gallium aluminum phosphide, (GaxA1(1 x)P), where X varies from 0 to 1. means for forward biasing said first and/or second light emitting junctions separately or simultaneously to cause light emission therefrom.

6. The multiple color light-emitting structure of claim 5 wherein the emission from said first light-emitting junction has a lower photon energy than from said second light-emitting junction and said second light-emitting junction is located closer to the light-emitting surface which interfaces with the media of transmission.

7. The multiple color light-emitting structure of claim 5 wherein said light-emitting junctions are of substantially the same area and in axial alignment with each other.