Comparative Study of GaN Based Light Emitting Devices Grown on Sapphire and GaN Substrates

Abstract

ABSTRACTThe homoeptaxial growth of GaN based devices has advantages against the heteroepi-taxial realization on substrates such as sapphire or SiC, since heteroepitaxy implies a lot of problems like lattice mismatch, different thermal expansion coefficients, and needs an extensive optimization of the growth at the heterointerface. In this paper we will discuss GaN based light emitting devices grown by homoepitaxy in comparison to devices grown on sapphire. We will show the differences in device performance, device processing and the influence of the thermal resistivity on the devices.