Gallium-containing light-emitting semiconductor device and method of fabrication
US7566576B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 17, 2008 |
| Grant date | Jul 28, 2009 |
| Priority date | — |
| Expiry date | Mar 17, 2028 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10H20/819
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
An LED comprising a light-generating semiconductor region having an active layer sandwiched between two confining layers of opposite conductivity types. A cathode is arranged centrally on one of the opposite major surfaces of the semiconductor region from which is emitted the light. An array of discrete gold regions are formed via transition metal regions on the other major surface of the semiconductor region at which is exposed one of the confining layers which is of n-type AlGaInP semiconductor material. The gold is thermally diffused into the confining layer via the transition metal regions at a temperature less than the eutectic point of gold and gallium, thereby creating an array of ohmic contact regions of alloyed or intermingled gold and gallium, which are less absorptive of light than their conventional counterparts, to a thickness of 20 to 1000 angstroms. After removing the transition metal regions and gold regions from the surface of the light-generating semiconductor region, a reflective layer of aluminum is formed so as to cover both the ohmic contact regions and the exposed surface portions of the AlGaInP confining layer. An electroconductive baseplate of doped silicon…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.