Influence of doping level on shift of the absorption edge of gallium nitride films (Burstein-Moss effect)

► Films of n-type GaN with different doping levels (E18-E20) were grown by ammonia MBE technique. ► Noticeable changing of energy position and slope (as broken line) of absorption edge were first revealed from ellipsometric spectra (ES). ► These features of absorption edge are impossible to find from transmittance spectra. ► Authors propose to predict electrical properties from ES using preliminary found correlation dependence between optical and electrical properties. ► It will be provided fast monitoring of expensive structures.