Comparative Study of Schottky Barrier Heights of the Different Metals Based on Porous Silicon Prepared by Photo-Electrochemical Etching (PECE)

摘要

In this paper, we present the fabrication of Schottky devices by the photo electrochemical etching of nano crystalline silicon layer on single-crystal silicon substrates. Porous silicon layers have been prepared from n-type silicon wafers of (111) orientation. XRD results revealed that the porous layer was nanocrystalline in nature. We have estimated crystallites size from X-Ray diffraction about nano-scale for porous silicon. Atomic Force Microscopy AFM shown the etching possesses inhomogeneous microstructures and confirms the nano-metric size. The influence of the inhomogeneous of porous layer on the Schottky barrier height, built in voltage, series resistance, shunt resistance, and donor concentration of the devices was studied. I-V methods and dark I-V measurements, which demonstrate good rectifying behavior. Measurements of Schottky barrier height from (I-V) and (C-V) of Au/PS-Si, Sb/PS-Si, and Sn/PS-Si structures (Heterojunction) have been described. The ideality factor of diodes which deduced from I-V characteristics confirms that the recombination current is dominated at low voltage. C-V investigations indicate that the diodes are abrupt type.