The formation of large-grain poly-silicon films on high-reflective alumina ceramics has been investigated by means of electron beam recrystallization technique. Sample structure is Poly-silicon layer/buffer layers (SiNx/SiOx) on Alumina ceramics substrate. These layers are deposited by high-rate Electron Cyclotron Resonance Plasma Chemical Vapor Deposition method, We have found that the SiOx layers act as a thermal buffer and an impurity contamination barrier against the ceramics, and SiNx layer has an important role in obtaining good wettability of molten silicon. We have also found that there are optimal thickness of buffer layers, scanning speed, and electron beam power to obtain good quality grains without agglomeration and cracks.