RF Linearity Analysis In Nano Scale CMOS Using Harmonic Balance Device Simulations

Abstract

In this thesis, Intermodulation Linearity characteristics of CMOS have been analyzed using power series and Harmonic Balance(HB) Method. Harmonic Bal- ance method is a frequency domain steady state analysis method used for solving nonlinear circuits. This method is extended to semiconductor device simulation using Taurus-Device tool. Third order Input Intermodulation Product (IIP3), a measure for linearity is characterized as a function of channel length, oxide thick- ness, drain and gate voltages using 130nm, 100nm and 90nm MOS devices. The effect of Polysilicon gate depletion on linearity is studied and analyzed for dif- ferent doping concentrations. Further, the simulated IIP3 values obtained from Harmonic Balance method are compared to the theoretical values calculated using power series.