Determination of tetragonal distortion of Al0.69In0.09Ga0.22N/GaN heterostructure by RBS/C and HRXRD

Rutherford backscattering/channeling spectrometry (RBS/C) was used to characterize the composition and structure of an Al0.69In0.09Ga0.22N/GaN crystalline film (κmin = 3.075%). The elastic strain induced tetragonal distortion value, eT, was determined by RBS/C and high resolution X-ray diffraction (HRXRD). Within the error range, the two methods gave fair agreement on the degree of strain. Comparing the two results, a possible correction due to a deviation for Vegard's law when large strain exists is discussed.