Abstract
Abstract Low temperature polycrystalline silicon thin films fabricated by metal induced crystallization method have been widely studied. But all related papers just discuss the effects of MILC method on the quality of poly-Si. Due to the limitation of low temperature, the quality of the poly-Si thin films cannot satisfy certain application. In this thesis we have discovered that by applying high temperature annealing to amorphous silicon with metal-induced-crystallization (MILC) treatment, the grain size and crystallinity of the resulting silicon can be significantly enhanced. In first section, we will discuss the phenomenon of the post high-temperature annealing on the MILC poly-Si thin films. From the Raman analyses, we have found that the crystallinity of poly-Si can be significantly improved with the increasing of the post-MILC annealing temperature. From the TEM images, we have found that after the post high-temperature annealing, the needle-like grains of MILC poly-Si thin films will be merged and the larger grains can be formed. These effects are due to the secondary grain growth of the poly-Si thin films. Finally, we established a possible model to explain the phenomenon of the secondary grain growth of MILC poly-Si. In the second section, we employ the in situ curvature measurement system to compare the strain variation between MILC and post-MILC annealing. The transition of stress curvature and the tendency of stress V.S. temperature relation have been examined in this study. We have found that the stress curvature of the substrate decreased during the MILC of a-Si thin film. On the other hand, the stress curvature of the substrates with the MILC poly-Si thin films increased during the post MILC annealing, In addition, the thickness of a-Si for MILC and the temperature of post-MILC annealing affect the curvature transition in the substrate. Finally, we also propose possible explanations of those effects.