On The Gate Capacitance Of MOS Structures Of n-Channel Inversion Layers On Ternary Semiconductors In The Presence Of A Quantizing Magnetic Field

Abstract

It is well-known that the gate capacitance of MOS strut tures of n-channel inversion layers on small ptap semiconductors is a very important one since the MOS capacitance can be very easily controlled by varying the gate voltage and also since it explores various other fundamental aspects of semiconductor surfaces in MOS structures. However, the gate capacitance of MOS structures on ternary semiconductors has relatively been less investigated in the literature and an attempt is made for the first time to investigate theoretically the above capacitance on ternary compounds by using the three-band Kane model. We have derived an expression of the surface electron statistics without any approximations of low or high electric field limits and taking into account the influence of the Dingle temperature respectively. We have then formulated a model expression of the magneto gate capacitance with the proper use of the electron concentration. We shall also formulate the same capacitance for both the limits excluding he broadening of Landau levels for the purpose of comparison. It is observed, taking n-channel inversion layers on Hg1-x Cdx Te as an example that the gate capacitance exhibits spiky oscillations with changinp, magnetic field and the oscillatory behaviour is in qualitative agreement with the experimental observation reported in the recent literature for MOS structure of Hg1-x Cdx Te. The corresponding results for n-channel inversion layers on relatively large band-gap semi-conductors both in the presence and absence of magnetic quantization can also obtained from the expressions derived.