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Highly (101)-oriented p-Ag 2 O thin film with high electrical resistivity was grown by rapid thermal oxidation (RTO) on clean monocrystalline p-type Si without any post-deposition annealing. From optical transmittance and absorptance data, the direct optical band gap was found to be 1.46 eV. The electrical and photovoltaic properties of Ag 2 O/Si isotype heterojunction were examined in the absence of any buffer layer. Ideality factor of heterojunction was found to be 3.9. Photoresponce result revealed that there are two peaks located at 750 nm and 900 nm.

Conductive transparent In 2 O 3 thin films with (222)-preferred orientation were prepared by rapid thermal oxidation (RTO) in static air of indium thin films at condition 200 • C/30 s. Detailed structural, electrical, and optical characteristics of the film are presented. The data are interpreted to give a direct bandgap of 3.6 eV and indirect bandgap of 2.5 eV. The grown In 2 O 3 films exhibited high figure of merit and sheet resistance as low as 20 Ω/sq. in the absence of any post-deposition annealing conditions. The mobility of these films was estimated to be 31 cm 2 · V −1 · s −1 . These results are compared with those of In 2 O 3 films prepared by other methods.

The photoluminescence spectrum of the freshly photosynthesized porous silicon (PS) has been investigated. This measurement was repeated after three and six months for the same sample after storage under ambient condition (open air at room temperature). Photoluminescence (PL) measurements of the stored PS show different peak positions and intensity width as compared with the results of the fresh PS. A blue shift in PL peak positions with aging time was observed. PL relative intensity is strongly diminished after 6 months of aging. Dark I-V characteristics of Al/PS/n-Si/Al structure shows a behavior of PS/n-Si isotype heterojunction for fresh device and a MIS (metal-insulatorsemiconductor) device due to contribution of Al/PS Schottky barrier after aging, essentially after 6 months.

Thin films of cadmium stannate (Cd2SnO4) have been deposited on glass substrates by pulsed Nd:YAG laser at room temperature. The deposited film was crystalline in nature and highly oriented in the (311) direction. Using this method, Cd2SnO4 films with the Hall mobility of 25 cm 2 V −1 s −1 and the carrier concentration of 6×10 20 cm −3 corresponding to the conductivity of 2.4×10 3 S cm −1 have been prepared without post-deposition thermal annealing. The films exhibited average optical total transmission of 70% in the visible region. The optical band gap was found to be 3.18 eV.