Sunday, September 28, 2008

US Patent 7427785 - Zinc oxide nanowire contact layer for LED

Transparent electrodes such as indium-tin-oxide are important to optoelectronic applications and are required to have both good optical transparency and electrical conductivity. This patent from Samsung teaches using high aspect ration nanostructures formed from zinc oxide as an improved transparent electrode material fro LEDs. Claim 1 reads:

1. A light emitting device comprising:

an n-type cladding layer;

a p-type cladding layer;

an active layer interposed between the n-type cladding layer and the p-type cladding layer; and

an ohmic contact layer contacting the p-type cladding layer or the n-type cladding layer and comprising a first film that comprises a transparent conductive zinc oxide having a one-dimensional nano structure, wherein the one-dimensional nano structure is at least one selected from a nano-column, a nano rod, and a nano wire.