Modeling of low energy-high dose arsenic diffusion in silicon in the presence of clustering-induced interstitial generation

Abstract

In this work we develop a simple macroscopic model for the prediction of arsenic diffusion in silicon under low energy-high dose implantation conditions. Under these conditions, As-enhanced diffusion is attributed mainly to interstitial injection due to the formation of As-vacancy clusters. The basis of the model is the introduction of a bulk interstitial generation source from the entire As distribution, taking into account the difference between the chemical and active profiles of the dopant during drive-in annealing. The model has been introduced to the SYNOPSYS-TAURUS process simulator in order to simulate the results of an experiment especially designed for this purpose. Very satisfactory simulation results have been obtained, taking into account the simplicity of the model. Moreover, the model predicts, at least for short annealing times, the initial stage (trend) of the well-known arsenic uphill diffusion phenomenon at the native oxide/silicon interface.