Reducing the Thermal Budget of Solid Phase Crystallization of Amorphous Si Film Using Si0.47Ge0.53 Seed Layer

Abstract
We have proposed a Si/Si0.47Ge0.53 bilayer (BL) structure as the active layer of thin-film transistor (TFT) to reduce the overall thermal budget of the solid-phase crystallization (SPC) of the conventional amorphous Si film. From X-ray diffractometry (XRD), we found that amorphous Si/Si0.47Ge0.53 bilayer film deposited onto thermal oxide by molecular beam epitaxy (MBE) was fully crystallized after an hour of annealing at 600° C. Furthermore, transmission electron microscopy (TEM) observation suggested that the evolution of grain microstructure was noticeably changed from dendrite to equiaxial growth mode by using Si0.47Ge0.53 seed layer compared to that observed for amorphous Si single layer (SL) with the same thickness.