Frequency-domain characterization of conductance and capacitance of resonant tunneling diode

An electrical characteristic that exhibits sharp discontinuity in its curve trace cannot be accurately characterized using conventional polynomial regression algorithms. The electrical characteristic of a resonant tunneling diode (RTD) is a typical example with sharp discontinuities in the negative differential resistance regions (NDR regions). The discontinuities in the NDR regions can easily create convergence failure and accuracy problems in frequency-domain simulation. In this paper, a continuity function based technique is proposed to characterize the strongly nonlinear electrical behavior of an RTD in the frequency domain. Particular reference is given to obtain a closed form CAD model that accurately simulates the high-order nonlinearities due to the discontinuities along the curve trace. Experimental evidence reveals that the frequency domain technique can yield a reliable first order estimate of the C-V characteristic.