Narrow Results

Transparent conducting indium tin oxide (ITO) films are deposited on Porous Silicon (PS) substrates by spray pyrolysis technique. In this process, the films are formed over the surface and also incorporated into the pores of PS and thereby making a protecting layer as well as a contacting terminal. Thus, the ITO/PS/Si heterojunction light-emitting devices are fabricated. The growth of ITO on PS is thoroughly investigated by SEM and X-ray diffraction techniques. The features of growth on other substrates like single-crystal p-type (100) silicon and glass are also taken into consideration. The influence on the PS interface is correlated with the electrical and luminescent behavior of the resulting heterojunction diode structure.

Indium tin oxide (ITO) thin films have been deposited on glass substrate by DC magnetron sputtering in the presence and absence of oxygen gas flux. Subsequently, some of the samples have been annealed in vacuum or air oven at $350^{\circ }$C for 20min. The optical, surface morphology and electrical characteristics have been examined by spectrophotometry, atomic force microscope, field emission scanning electron microscopy, four-point probe and Hall effect measurements as a function of argon gas flux, film thickness, deposition rate and substrate temperature. Experimental results indicate that the surface roughness increases by decreasing the argon gas flow rate and deposition rate. The result revealed that the lowest surface roughness of 1.07nm is achieved at zero oxygen gas flux, argon gas flow 20sccm and deposition rate $0.5$ Å/s. We have found that the maximum value of merit figure is related to the argon gas flow rate 30sccm. In order to obtain a very smooth surface, finally, the ITO thin films have been processed with alumina polishing solution by ultrasonic method. Our experimental results indicate that surface roughness decreases and merit figure increases after polishing process.