  This paper presents a self-consistent numerical model for calculating the
charge profile and gate capacitance and therefore obtaining C-V
characterization for a gate-all-around graded nanowire MOSFET with a high
mobility axially graded In0.75Ga0.25As + In0.53Ga0.47As channel incorporating
strain and atomic layer deposited Al2O3/20nm Ti gate. C-V characteristics with
introduction and variation of In-composition grading and also grading in doping
concentration are explored.Finite element method has been used to solve
Poisson's equation and Schr\"odinger's equation self-consistently considering
wave function penetration and other quantum effects to calculate gate
capacitance and charge profile for different gate biases. The device parameters
are taken from a recently introduced experimental device.
