Analysis of piezoelectric fields of GaInN/GaN quantum wells using hard X-ray photoelectron spectroscopy

Abstract

In order to evaluate piezoelectric fields of GaInN/GaN quantum well structures, we have developed an analysis method that combines hard X-ray photoelectron spectroscopy with spectrum simulation. We also estimated the In compositions of the GaInN layer using X-ray diffraction and investigated the correlation with piezoelectric fields. It was confirmed that there is a tendency for the piezoelectric field to increase as the In compositions of the GaInN layer increase among green and orange light-emitting samples. For red light-emitting samples, on the other hand, it was found that the piezoelectric field decreases compared to orange samples, which is because of the relaxation of lattice distortion in the GaInN layer.