  In this paper, Capacitance-Voltage (C-V) characteristics and direct tunneling
(DT) gate leakage current of antimonide based surface channel MOSFET were
investigated. Self-consistent method was applied by solving coupled
Schr\"odinger-Poisson equation taking wave function penetration and strain
effects into account. Experimental I-V and gate leakage characteristic for
p-channel InxGa1-xSb MOSFETs are available in recent literature. However, a
self- consistent simulation of C-V characterization and direct tunneling gate
leakage current is yet to be done for both n- channel and p-channel InxGa1-xSb
surface channel MOSFETs. We studied the variation of C-V characteristics and
gate leakage current with some important process parameters like oxide
thickness, channel composition, channel thickness and temperature for n-channel
MOSFET in this work. Device performance should improve as compressive strain
increases in channel. Our simulation results validate this phenomenon as
ballistic current increases and gate leakage current decreases with the
increase in compressive strain. We also compared the device performance by
replacing InxGa1-xSb with InxGa1-xAs in channel of the structure. Simulation
results show that performance is much better with this replacement.
