Interstitial Defect Reactions In Silicon

Abstract

AbstractThe interaction between self-interstitials (Sii), impurities, and dopants in Si leads the formation of undesirable point defects which affect device operation. Electron beam irradiation has been used to generate Sii and initiate defect reactions, and the hierarchy and competition of interstitial defect reactions involving O, C, B, and P in Si have been explored by DLTS measurements. We describe the interstitial defect reactions as a three-step process: (i) displacement reaction for the generation of Sii, (ii) Watkins replacement reaction for the generation of C and B interstitials (Ci and Bi), and (iii) diffusion limited reaction for the formation of pairs. Within the framework of reaction kinetics, for the first time, we have successfully set up a nonlinear system model to simulate the reaction processes. The interstitial migration enthalpy and the pair formation capture radius are two parameters used in the model to describe long range migration and near neighbor interaction. The good agreement between the model and experiments not only supports the defect assignments by DLTS, but also provides an initial glimpse into the interaction of point defects in Si.