High density matrix-addressable AllnGaN-based 368-nm microarray light-emitting diodes

We report on the fabrication of ultraviolet (UV) microarray light-emitting diodes, toward applications including mask-free photolithographic exposure. Devices with 64 /spl times/ 64 elements have been fabricated in matrix-addressed format, generating directed output powers of up to 1 /spl mu/W per 20-/spl mu/m-diameter element at less than 1.0-mA drive current. The resistance of each elemental device was found to depend strongly on the n-GaN stripe length. The center wavelength of the emission was measured to be 368 nm, which is very close to that of an i-line (365 nm) UV light source. To our knowledge, this is the first report detailing the fabrication and performance of such devices operating in the UV.