Structural changes due to reannealing of Ge thin films prepared by solid phase epitaxial growth on Si (111) surface

Abstract

We investigate effects of annealing and reannealing temperatures on the Ge film with thickness of 3 bilayer prepared by the solid phase epitaxial growth on Si(111) substrate. Intermixing of Ge and Si is suppressed up to 400°C, but is clearly observed at 425°C. The wetting layer with thickness of 2 bilayer formed during the annealing at 400°C has many defects due to stacking faults in the Si(111) 7×7 structure on the substrate. By reannealing at 600°C, the defects can be removed while suppressing intermixing. The recrystallization mechanism is discussed from the morphological and structural changes of the Ge film by reannealing at temperatures up to 600°C.