Selective Area Growth of GaN on Stripe-Patterned (111)Si Substrate by Metalorganic Vapor Phase Epitaxy

Abstract

Selective area growth of GaN on stripe-patterned (111)Si substrate has been studied by metalorganic vapor phase epitaxy. When the stripe is along the 〈11-0〉 direction of the Si substrate, a GaN stripe with triangular cross-sectional shape is obtained without cracks or pits. The full-width at half-maximum of X-ray rocking curves is much reduced as compared to that for uniform GaN layer on un-patterned Si substrate. This result indicates that c-axis fluctuation due to the columnar structure of GaN is much suppressed by the selective area growth. Photoluminescence spectra of GaN stripes reveal the red-shift and the broadening of full-width at half-maximum in comparison with thin GaN layer on sapphire substrate. This suggests that the tensile strain due to heteroepitaxy is applied to the GaN stripe on the Si substrate.