The effects of interfacial oxide layers on the Al-induced crystallization (AlC) of amorphous Si1-xGex (x: 0-1) films on an insulator at a low temperature (<500 degrees C) have been investigated. In the case of Si, the inversion of the Si/Al layers was achieved for samples with and without interfacial oxide layers between the Si and Al layers. In addition, it was found that the existence of interfacial oxide layers was required to obtain large grain (similar to 100 mu m) polycrystalline Si with a (111) orientation. However, in the case of SiGe, the interfacial oxide layers significantly retarded AlC growth. Consequently, layer exchange occurred inhomogenously, which resulted in inhomogenous crystallization even after a long annealing time (410 degrees C, 100 h). To solve this problem, the effects of interfacial oxide thickness on AlC growth were investigated. As a result, complete layer exchange was achieved for samples with the whole Ge fractions (x: 0-1) by controlling the air exposure time. A qualitative model is presented. (C) 2009 The Japan Society of Applied Physics