Schottky Barriers on Layered Anisotropic Semiconductor – WSe₂ – with 1000 Å Indium Metal Thickness

Achamma John Mathai, Chalappally Kesav Sumesh, Bharat Purushotamds Modi

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Department of Applied Physics, Indian School of Mines, Dhanbad, India.

DOI: 10.4236/msa.2011.28135                

Abstract

We have studied the forward I-V characteristics of In-pWSe₂Schottky barrier diode with 1000 Å indium thickness in the temperature range 140 – 300 K well within the domain of thermionic emission theory with Gaussian distribution of barrier height. However we found some anomalies in the low temperature range below 200 K. Hence we have considered a model that incorporates thermionic emission, generation recombination and tunneling components. The low temperature anomalies observed in the diode parameters were effectively construed in terms of the contribution of these multiple charge transport mechanisms across the interface of the fabricated diodes. Various Schottky diode parameters were also extracted and compared with that of 500 Å metal thickness In-pWSe₂ diode.

Keywords

Schottky Diodes, Interface, Inhomogeneities, In-Pwse₂, Metal Thickness, Current-Voltage, Thermionic Emission, Generation Recombination, Tunneling, Gaussian Distribution.

Conflicts of Interest

The authors declare no conflicts of interest.

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