Epitaxial GaN layers were grown by metallorganic vapor phase epitaxy on Si(111) substrates by using aluminum oxide (AlOx) buffer layers. The AlOx was obtained by anodic oxidation of an evaporated Al film. High-resolution X-ray diffraction and room temperature photoluminescence measurements were used to investigate the grown GaN layers. Epi-growth of GaN on the AlOx stripes was shown to be possible, while no growth took place on the neighboring Si surface, hereby demonstrating perfect selectivity. (c) 2005 The Electrochemical Society.