Process Modeling of n‐Type Doping in Gallium Arsenide

Abstract

Empirical models have been developed for predicting the carrier distributions after ion implantation and annealing process steps used in device fabrication. The present models predict the carrier distributions for n‐type using Si and Se as the dopants. The simulation is done by using the atomic profile and activation efficiency models developed in this study. These models are based on SIMS and measured carrier concentration profile studies reported in the literature. The model for atomic distribution provides a gaussian profile for Si and a joined half‐gaussian one for Se using the projected range and standard deviation parameters obtained from SIMS studies. The effect of radiation enhanced diffusion is taken into account. Impurity diffusion during annealing for temperatures up to 920°C for Si and 1000°C for Se is neglected. Volumetric concentration has been properly chosen as a canonical parameter for obtaining activation efficiency. The universal activation efficiency plots for each dopant species give percentage activation efficiency as a function of atomic concentration (cm−3) at different annealing temperatures.