Transport based equivalent circuit models for waveguiding structures on a semiconductor substrate

As the frequency of operation for analog integrated circuits (IC) reaches the millimeter-wave band, while a corresponding rise-time is achieved by the digital counterpart, propagation effects in devices and ICs need to be accounted for with higher precision than that attained ever before. From a full-wave formulation, based on the coupling of the transport equations of the carriers to the Maxwell´s equations, equivalent circuit models for canonical waveguiding structures on semiconductor substrates are developed. Asymptotic considerations given to the limiting cases of zero and high-level doping, as well as excitation by a static field can serve as an effective means to select the appropriate equivalent circuit, while providing insight to the physical relevance of the circuit elements to carrier interactions with the field.