Dopant effects on solid phase epitaxy in silicon and germanium

Johnson, B. C.; Oshima, Takeshi; McCallum, J. C.*

The kinetics of dopant-enhanced solid phase epitaxy (SPE) in amorphous germanium (a-Ge) and silicon (a-Si) layers which are created by ion implantation are investigated. Implanted Sb atoms as dopants into a-Ge at concentrations up to 110/cm are considered and compared to As-implanted layers with similar concentration of As atoms. Although an active Sb concentration above the solubility limit is achieved, a significant portion of the implanted atoms are not. P, As, and B atom enhanced SPE rates in Si are also analyzed. The relative velocities of P and As in Si are similar to those of As and Sb in Ge. Theoretical predictions on the basis of a simple form of the generalized Fermi level shifting model well agree with the results experimentally obtained in this study.