Study Of Organic Monolayer Modified Metal Oxide Semiconductor Devices   For High Temperature Applications
  We report fabrication and characteristics of an organic monolayer based Metal Oxide Semiconductor (MOS) device. In place of SiO2 oxide layer in the MOS configuration, we used 1H, 1H, 2H, 2H- perfluorooctyl trichlorosilane (FOTS) self-assembled monolayer as a substitution. The MOS device was fabricated by simple steps like sputter deposition and dip coating method. The device was heat treated to different temperatures to understand its performance and efficiency for high temperature application. The MOS device was heated to 150{\deg} C, 350{\deg}C and 550{\deg}C and the energy band gap was found to be varied in the order 2.5 eV, 3.0 eV and 3.4eV respectively. For non-heated sample, the energy band gap is 3.4 eV. The results shows that the parameters like charge mobility ({\mu}), energy band gap, and resistance were found to be decreased after the heat treatment. The change in the energy band gap due to heat treatment has significantly influenced the I-V and the impedance characteristics. We observed that the MOS device started to conduct between 1V to 3V, further the device conduct till 20V. Impedance analysis show that device heated to 350 {\deg}C shows the low impedance but the impedance starts to increase for further heating up to 550{\deg}C. Using Multi Dielectric Energy Band Diagram Program (MEBDP) we studied the MOS structure and C-V characteristics and temperature dependent behavior of the devices from 100K to 600K. Our experimental work and simulation studies confirm that the FOTS SAM substituted MOS device could be used for high temperature applications. The experimental observations are well supported by the simulation results. This study shows that the FOTS organic monolayer are promising substitute for SiO2 oxide layer in the MOS and MOSFET which could be used high temperature applications. 
Rosilin George, U. Satheesh, J. Cyril Robinson Azariah, D.Devaprakasam
cond-mat.mes-hall