Study of Hole Traps In P-type ZnSe and Znsse Epilayers by DLTS and Admittance spectroscopy

摘要

We Studied nitrogen doped ZnSe and ZnSse epilayers grown on p-GaAs substrates by MBE suing deep-level transient spectroscopy and admittance spectroscopy. Three major hole traps T1-T3 were observed with energy levels at 0.11, 0.46, and 0.56eV fro mthe valence band. Similar energy levels were observed in ZnSse:N except that T1 was at 0.12eV from the valence band. We attribute T1 to a nitrogne acceptor whihc ocntrols the p-type conduction in the materials. A crude estimation of the 0.11 eV trap concentration obtained from the data shows correlation with the free carrier concentration due to nitrogen. The two remaining levels may originate from the nitrogen doping process.