ULTRAVIOLET AND VIOLET GAN LIGHT-EMITTING-DIODES ON SILICON

We report the fabrication and characterization of GaN-based double het erostructure light emitting diodes grown by molecular beam epitaxy on Si(111) substrates. Light emitting diode operation is achieved by usin g the conducting Si(111) substrate as a backside n contact and a stand ard transparent Ni/Au p contact. We observe electroluminescence peaked in the ultraviolet similar to 360 nm, with a full width at half maxim um of similar to 17 nm and in the violet at similar to 420 nm. Electro n microscopy studies indicate a high density of threading and planar d efects. Consequences of these are discussed. (C) 1998 American Institu te of Physics.