Oxidation enhanced and concentration dependent diffusions of dopants in silicon

Diffusions of impurities in silicon under oxidizing ambient and under extrinsic conditions have been analyzed by developing the Hu’s model. The general expression of diffusion coefficient, which includes both the vacancy and interstitialcy mechanisms, is used. The temperature dependences of a fraction of interstitialcy mechanism for arsenic fAs, phosphorus fP, and boron fB are obtained from the data of oxidation enhanced diffusion (OED) and oxidation induced stacking faults. fAs =42 exp(−0.542/kT), fP =156 exp(−0.666/kT), and fB =860 exp(−0.829/kT). Time dependence of OED and the concentration dependence of the diffusion coefficient of arsenic and boron under extrinsic conditions can be explained by this model.