Non-doped (1-101)GaN and C-doped (1-101)GaN thin film samples were grown by a selective metal-organic-vapor-phase-epitaxy (MOVPE) method on 8˚off-oriented (001) Si substrate. In This study, we identify the E_g of the GaN thin films on Si substrate by photoreflectance (PR) and photoluminescence (PL) methods. From the fitting analysis to the obtained PR spectrum, the estimated values of critical energy (E_cr) of GaN film grown on Si substrate were approximately 1 meV lower than expected values for strain-free GaN bulk sumple. Exciton peak positions of non-doped and C-doped (1-101)GaN grown on Si substrate corresponded exactly to strain-free GaN bulk sample. These experimental results implied that the strain caused by the lattice mismuch between GaN and Si were relaxed in the GaN surface resion.
雑誌名
宮崎大學工學部紀要
巻
42
ページ
23 - 26
発行年
2013-08-30
出版者
宮崎大学工学部
Miyazaki University
Faculty of Engineering, University of Miyazaki