Electrical Study of Al/n-ZnS Schottky Junction on Polymer Substrate

Sandhya Gupta; N.S. Saxena; Kananbala Sharma

doi:10.6000/1929-5995.2013.02.02.4

Authors

Sandhya Gupta Kautilya Institute of Technology & Engineering, Jaipur-302022, India
N.S. Saxena Semiconductor & Polymer Science Laboratory, Dept. of Physics, University of Rajasthan, Jaipur-302004, India
Kananbala Sharma Semiconductor & Polymer Science Laboratory, Dept. of Physics, University of Rajasthan, Jaipur-302004, India

DOI:

https://doi.org/10.6000/1929-5995.2013.02.02.4

Keywords:

Schottky barrier, Optical properties, Thermionic emission, Polyethylene terephthalate, Band gap

Abstract

A study has been made on the behaviour of Al/n-ZnS thin film junction on Polyethylene terephthalate (PET) grown using thermal evaporation method. Current-Voltage (I-V) characteristics of this junction show that the Aluminium (Al) makes Schottky contact with n-ZnS (Zinc Sulfide). Intrinsic and contact properties such as saturation current, barrier height, ideality factor and series resistance were calculated from the I-V characteristics. The conduction seems to be predominantly due to thermoionic emission-diffusion mechanism. An effort has also been made to carry out the optical study of ZnS thin film using spectrophotometer. Band gap of n-ZnS thin film is determined through absorption spectra using the Tauc’s extrapolation. A band diagram of Al/n-ZnS has been proposed using the so obtained data.

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