Lattice deformation of wurtzite MgxZn1−xO alloys: An extended X-ray absorption fine structure study

Abstract Synchrotron extended X-ray absorption fine structure (EXAFS) of Zn K -edge and X-ray diffraction (XRD) have been employed to study the lattice deformation of wurtzite Mg x Zn 1− x O alloys (0 ⩽  x  ⩽ 0.14) grown on sapphire substrates by metalorganic chemical vapor deposition (MOCVD). Our results reveal that Mg concentration increasing leads to the enhancement of σ -bonding of Zn–O and lattice constant a while resulting in depression of π -bonding of Zn–O and lattice constant c . With increasing from x  = 0 to x  = 0.14, the c / a ratio significantly decreases from 1.6014 to 1.5906, while the internal parameter u decreases only slightly from 0.3826 to 0.3820. This suggests that the u has a much smaller sensitivity for dilute Mg substitution.