An n-type WO3 thin film on a p-type GaAs substrate has been investigated in terms of its structural, electrical, and photocurrent-voltage characteristics. Crystallization of the monoclinic phases of WO3 occurred at 400°C as identified by a glancing angle x-ray diffractometer. Above 400°C, small traces of gallium oxide (Ga2O3)were observed along with higher intensities of the monoclinic peaks. The formation of Ga2O3 was confirmed by a depth profile analysis using an Auger electron spectrometer. Electrical resistivity measured by the van der Pauw method was influenced by the crystalline nature and the interfacial states induced by the diffused atoms from each side of WO3 and GaAs. A high photocurrent density of 7.5 mA/ cm2 at -1.0 V (vs SCE) appeared at the crystalline WO3 on p-type GaAs at 400°C resulting from effective carrier movement through the interfaces.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy (miscellaneous)