Modified linear transmission line model test structure for determining specific contact resistance

A modified design of the transmission line model test structure uses the simple calculation of specific contact resistance, ρc, based on a two contact linear pattern but without the requirement of a mesa etch. This modified structure uses a linear TLM with semicircular terminations at each end. The function of the semicircular terminations is to confine the fringing fields at the ends of the linear TLM contacts. Simple analytical equations for determining ρc have been developed on the basis of the modified linear TLM pattern. These calculations have shown good agreement with a finite element model (FEM) of the modified TLM test structure using typical parameters for metal/ SiC contacts