Light-emitting diode which generates light in three dimensions

• US 3,900,863 A
• Filed: 05/13/1974
• Issued: 08/19/1975
• Est. Priority Date: 05/13/1974
• Status: Expired due to Term

• Current Assignee: Philips Electronicsnorth America Corporation (Koninklijke Philips N.V.)
• Original Assignee: He B. Kim
• Inventors: Kim, He B.
• Primary Examiner(s): Edlow, Martin H.
• Application Number:
  US05/469,588
• Time in Patent Office: 463 Days
• Field of Search: 357/17,18,56,60,16 148/175
• US Class Current: 257/95
• 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: Y10S 148/026 Deposition thru hole in mask
• CPC Class Codes: Y10S 148/056 Gallium arsenide
• CPC Class Codes: Y10S 148/065 Gp III-V generic compounds-processing
• CPC Class Codes: Y10S 148/072 Heterojunctions
• CPC Class Codes: Y10S 148/085 Isolated-integrated
• CPC Class Codes: Y10S 148/115 Orientation

Abstract

Light-emitting diode (LED) device generates light proximate a plurality of different surfaces which lie in different planes. The device is formed on a substrate of a n-type material which carries a thin dielectric masking material thereon with apertures in the mask. Epitaxial facet grown islands project through the apertures and a thin layer of p-type material is formed thereover to provide light-emitting p-n junctions which lie in different planes.

Claims

1. A LIGHT-EMITTING SOLID-STATE DIVICE WHICH WILL GENRATE LIGHT PROXIMATE A PLURALITY OF DIFFEENT SURFACES WHICH ARE IN MORE THAN ONE PLANE, SAID DEVICE COMPRISING:

A. A SUBSTRATE FORMED OF PREDETERMINED N-TYPE MATERIAL HAVING A SELECTED SURFACE OF PREDETEMINED CRYSTALLOGRAPHIC ORIENTATION, B. A THIN LAYER OF INORGANIC DIELECTRIC MATERIAL ADHERED OVER SAID SELECTED SURFACE OF SAID SUBSTRATE, SAID THIN LAYER HAVING PROVIDED THEREIN AT LEAST ONE APERTUNE OF PREDETERMINED SIZE AND CONFIGURATION AND POSITIONED IN PREDETERMINED CRYSTALLOGRAPHIC ORIENTATION WITH RESPECT TO SAID SELECTED SURFACE, C. AN EPITAXIAL FACET GROWN ISLAND OF SAID N-TYPE MATERIAL EXTENDING FROM SAID SUBSTRATE AND PROJECTING A PREDETERMINED DISTANCE THROUGH AND BEYOND THE APERTURE IN SAID DIELECTRIC LAYER, D. A THIN P-TYPE LAYER OVERLAYING THE PORTIONS OF SAID ISLAND WHICH PROJECT BEYOND THE APERTURE IN SAID DIELECTRIC LAYER, WITH THE BOUNDRY BETWEEN SAID N-TYPE MATERIAL AND SAID P-TYPE LAYER DEFINING A MULTIPLANAR LIGHT-EMITTING P-N JUNCTION, E. FIRST METALLIC ELECTRODE MEANS CONTACTING SAID P-TYPE LAYER, AND F. SECOND METALLIC ELECTRODE MEANS CONTACTING ANOTHER SURFACE OF SAID SUBSTRATE.

2. The device as specified in claim 1, wherein there are provided a plurality of said apertures in said dielectric material layer, said apertures when viewed in combination providing a predetermined array desired to be visually presented, each of said apertures have one of said epitaxial facet grown islands projecting therethrough, and said first metallic electrode means comprising a plurality of different electrodes adapted to be separately energized.

3. The device as specified in claim 1, wherein said epitaxial facet grown island has a predetermined faceted lens structure.

4. The device as specified in claim 3, wherein at least a portion of said faceted lens structure has provided thereon a thin layer of material having an index of refraction intermediate the indicies of refraction of said p-type layer and air.

5. The device as specified in claim 1, wherein said substrate is gallium-arsenide and of flattened configuration, with the crystalline Miller indicies of said selected surface being (001);

said dielectric material is silica affixed to said selected surface;

said p-type layer is zinc doped gallium-arsenide;

said first metallic electrode means is gold-germanium alloy; and

said second metallic electrode means is gold-germanium alloy and is affixed to a surface of said substrate opposite said silica layer.

6. The device as specified in claim 1, wherein said device is formed of different layers of heretrogeneous composition, said island is different composition than said substrate and said island has an energy gap greater than the energy gap of said substrate, said thin p-type layer has an energy gap lEss than the energy gap of said island, a window layer of p-type material of composition different from that of said thin p-type layer overlays said thin p-type layer, and said window layer has an energy gap greater than that of said thin p-type layer.