Effect of surfactant on Ge crystallization on Si in solid phase epitaxy

We have studied the influence of surfactant on solid phase epitaxy of an amorphous Ge layer on Si(111) using in situ scanning electron microscopy. A monolayer of As overlayer deposited on the amorphous Ge layer raises the Ge crystallization temperature by up to 100 K both on 7x7 and ''1x1'' regions, as well as suppresses islanding of Ge. The crystallization temperature raise is discussed as pining of the surface by As inhibiting the movement of excess volume during crystallization of the amorphous Ge layer. (C) 1997 Elsevier Science B.V.