Characterisation of Schottky Diode Performance by Numerical Simulation Coupled with Harmonic Balance

Abstract
The electrical and RF performance characteristics of submillimetre-wave Schottky diodes are investigated using an accurate physical model which combines drift-diffusion current transport with thermionic and thermionicfield emission currents imposed at the Schottky contact. The model includes self-consistently image force effect, tunneling transport, and current dependent recombination velocity at the Schottky contact. This physical simulator has been coupled to a harmonic balance simulator as a non-linear element. The integrated device-circuit simulator has allowed to study in detail the limiting factors of varactor operation. The contribution of large-signal capacitance excitation is discussed. The influence of external loads at different harmonics, bias and power level is also analysed.