Electrical characteristics of al-siox-psi devices and solar cells

Current-voltage (I-V) and capacitance-voltage (C-V) characteristics have been examined in the temperature range of 295-375 K for metal-insulator-semiconductor (MIS) solar cells with an interfacial oxide thickness of 20-30 A. In the intermediate bias voltage region, the semilogarithmic plot of dark I-V curves were found to be linear and the slope was almost independent of temperature. The diode quality factor n, strongly temperature dependent changing linearly with inverse temperature. And also, the reverse saturation current Io changes linearly with temperature. Analysis of the data indicated that predominant carrier transport mechanism of solar cells for the temperature range 295-375 K in the intermediate bias voltage region investigated in this work was multistep tunneling rather than usual process of diffusion. In addition MOs structures with an interfacial oxide thickness of 70-660A have been fabricated on silicon wafer in order to determine the interface state distribution Si and SiO2 by the use of various techniques. The magnitude and profile on the interface states densities are quite different for the samples having different oxide thickness fabricated on the substrate from the same batch under different oxidation temperatures. Despite the apparent disagreement in the interface state density distribution profile for the samples oxidized and different temperatures. However, there was a good agreement in the interface state density distribution between the high-low frequency capacitance and conductance techniques for each sample. This indicated the reliability of the observed interface state density profiles.