DESIGN AND COMPARISON OF ADVANCED SEMICONDUCTOR-DEVICES USING COMPUTER EXPERIMENTS - APPLICATION TO APDS AND HEMTS

We present a “computer experimental procedure” that is useful for studying the behavior of advanced semiconductor devices that contain nonlinear effects. Our approach draws on our previous work, in modeling avalanche photodiodes (APD's) and high electron mobility transistors (HEMT's) based on an ensemble Monte Carlo model. We present an overall approach to modeling these devices emphasizing the built-in controls and the importance of “bootstrapping” the model. The approach is not limited only to APD's and HEMT's, however, because virtually any semiconductor device can be successfully modeled following this procedure. As a means of illustrating the usefulness of this “computer experimental technique,” we review previous device calculations as well as present new results. Computer experiments that either compare the performance of different device designs or enable the optimization of an existing structure are presented. Specifically, the optimal operating point of a GaAs/AlGaAs-doped quantum-well APD is bracketed. Comparison of otherwise identical HEMT devices, differing only in the constituent materials, is also presented. It is found that both the APD and HEMT models favorably compare with existing experimental measurements and as such provide an accurate picture of the device operation. In this way, various device structures can be analyzed prior to their experimental realization. Through “computer experiments” such as those outlined here, the effect of various geometries and material compositions on device performance can be assessed and optimal designs achieved. © 1990 IEEE