Modeling of GaAs Schottky diodes for terahertz application

3-D models have been developed to study the series resistance (R_s) at DC and the extrinsic parasitic elements (capacitance and inductance) at high frequencies for a Schottky diode chip. For the R_s study, a comparison with the experimental result has been carried out. High frequency properties and the corresponding S-parameters of the Schottky diode chip are simulated using a 3-D finite element electromagnetic solver. The parasitic elements are then extracted and studied as a function of the diode geometry. The outcome of the studies shows the existence of a significant pad-to-pad capacitance through the semi-insulating substrate which could be improved by implementing tapered shape pads.