Clustering Equilibrium and Deactivation Kinetics in As doped Si

Abstract

AbstractClustering equilibrium was studied on silicon on insulator specimens uniformly doped with As at concentrations CAs up to 7.6 × 1020 cm−3. Values of the carrier density n* after equilibration at 700, 800 and 900°C are reported. It is shown that both the concentration and the temperature dependence of n* can be accurately simulated by a simple cluster model detailed in the Appendix. The analysis of the clustering kinetics of these compositions was performed at temperatures in the range 550 to 800°C. It is found that at 800°C the kinetics accurately complies with the rate equation:-dn/ dt = A{exp[-(E-αn)/kT] - (n0- n)/( n0- n*) exp[-(E-αn*)/kT]which is the one reported in Ref.[14] complemented by the second term on the right to account for the declustering process. Deviations leading to rates lower than predicted by the above equation are observed by annealing at lower temperatures. The dependence of this phenomenon on composition and temperature is reported.