Optical Studies of GaAs Nanowires Grown on Trenched Si(001) Substrate by Cathodoluminescence

Abstract

"The strains in GaAs nanowires, which were grown from 1700- to 80-nm-wide trenches on the Si(001) wafer with SiO2 masks, were investigated by cathodoluminescence. For 1700- to 500-nm-wide trenches, the in-plane tensile strain at 15 K decreases with the decreasing trench width. The strain increases abruptly when the trench width is 300 nm, and then decreases as the trench width is further decreased. The results revealed that the stress induced by the SiO2 sidewalls dominates when the width is less than the depth of the trench. This approach provides an effective technique to measure the strain of a single nanowire and helps for the demonstration of selectively-grown GaAs with a designed strain. (C) 2012 The Japan Society of Applied Physics"