Dislocation reduction in GaN with double Mg x N y /AlN buffer layer by metal organic chemical vapor deposition

Abstract: Unintentionally doped GaN with conventional single low-temperature (LT) AlN buffer layer and with double Mg x N y /AlN buffer layers both were prepared. It was found that we could reduce defect density and thus improve crystal quality of the GaN by using double Mg x N y /AlN buffer layers. GaN with double Mg x N y /AlN buffer layers reveals an asymmetrical reflection (102) and (002) with a smaller full-width at half-maximum (FWHM), and a higher mobility, lower background concentration and lower etching pit density (EPD) than the GaN with the LT-AlN buffer layer. [Copyright &y& Elsevier]