Micro-UVLED Arrays for Solid State Lighting


A micro-machined silicon nanostructure can provide a suitable nucleation site for compound semiconductor heteroepitaxy when grown from the vapor phase. The nucleation region can be reduced to sub-micron dimensions where direct bandgap AlGaN structures can be grown, and are believed to be defect free, in spite of considerable lattice and thermal mismatch. The resulting six-sided pyramids (roughly 1 micron at the base) have luminescence yields some three orders of magnitude higher than conventional planar heteroepitaxial films on silicon. The fabrication technology used to realize massively paralleled LED arrays on silicon will be described.