Effects of local Ge-insertion in a-Si films on solid-phase crystallization (SPC) were investigated. Three types of stacked structures, i.e. (a) a-Si/a-Ge/a-Si/SiO2, (b) a-Si/a-Ge/SiO2 and (c) SiO2/a-Gc/a-Si/SiO2 were fabricated and annealed at 600 degreesC. The results for the structure (a) showed that Ge atoms diffused into the Si layers, and no-enhanced SPC was detected. On the other hand, the results for the structures (b) and (c) indicated that Ge atoms were localized in the initial position. In addition, significant enhancement of SPC of a-Si was found. These results indicated that crystal nucleation was initiated at Ge layers directly contacted to SiO2 and then propagated into a-Si layer. Consequently, interface nucleation driven SPC becomes possible by using the structures (b) and (c). This will be a useful tool to achieve growth of Si crystals with a preferential orientation on siO(2). (C) 2003 Elsevier B.V. All rights reserved.