We have performed new modulation photocurrent (PC) and current-voltage (I-V) measurements on 1 μm thick ZnSe epilayers grown on a (100) GaAs substrate, which are sensitive to interfacial properties. When the sample was modulated by the pump beam whose energy is between that of the ZnSe and GaAs bandgaps, the intensity of the PC signals only above the ZnSe absorption edge increased. Through the analysis on the modulation mechanism we showed the existence of trap states at the interface and its strong influence on the current flow in the epilayers. In addition, we observed states localized at the interface by the modulated PC spectrum. The possible mechanisms of the modulation were also discussed.
|Number of pages||4|
|Journal||Physica Status Solidi (B) Basic Research|
|Publication status||Published - 2002|
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics