Predicting and diagnosing performance of transistors, integrated circuits and large-scale-integration systems by multilevel simulation methods and programs

Application of multilevel simulation methods and programs to discrete transistors as well as to integrated circuits and large-scale-integration systems is considered, for effective performance and reliability evaluation on the basis of technological, physico-topological, or componential models. To predict and diagnose the behavior of such devices, it is necessary to determine the sensitivity of electrical characteristics on design, structural, and fabrication factors. The most important factors are increase of the perimeter-to-area ratio of the emitter, adequately high doping levels in all three emitter-base-collector regions, and moderately high collector-junction breakdown voltage. Multilevel simulation by the method of informative parameters makes it possible to estimate relative increases of the surface-recombination component of the base current, relative increases of the peripheral minority-carrier injection current, effects of high doping and injection levels, and effects of low collector-junction breakdown voltage of thin-film semiconductor structures.