investigation of ac and dc electrical properties and surface morphology of al/tio2/psi/al nanostructure

in this research work nano porous silicon layers with different porosity were prepared by using electrochemical etching. surface morphology and size of pores were investigated by scanning electron microscopy (sem).tio2 thin films with ebpvd method have been deposited on the surface of psi layers. the influence of anodization conditions such as anodization time interval and current density on electrical properties and surface morphology of sandwich devices were carried out using i-v measurement .the results showed that, electrical properties were influenced by changes of current density and anodization time interval. we also investigated the ac electrical conductivity of al/tio2/psi/al sandwich devices over the range of frequency 102 to 105 hz and temperature range 300 to 378 k. it is known that, over the range of frequency < 103hz the band theory and over the range of frequency > 103hz hopping mechanism is applicable in explaining the conductivity of tio2/psi thin films nano structures with aluminum electrodes.