Fabrication of Low-Temperature Poly-Si Thin-Films Using Hot-Wire CVD and Al-induced Crystallization Techniques

• Main Authors: jui-hao Wang, 王瑞豪
• Other Authors: D. S. Wuu
• Format: Others
• Language: zh-TW
• Published: 2005
• Online Access: http://ndltd.ncl.edu.tw/handle/99574835223515040275

碩士 === 國立中興大學 === 材料工程學研究所 === 93 === The study utilized hot-wire chemical vapor deposition (HWCVD) which mixed different ratio of SiH4 and H2 to deposit Si-film rapidly and also used aluminum-induced crystallization (AIC) to fabricate high-quality polycrystalline silicon (poly-Si) films which served as a seed layer and accumulated large grain poly-Si films quickly above the seed layer. The purpose of the study was to investigate the change of AIC thin films due to different annealing time and temperature, and to further analyze characteristics by X-ray diffraction (XRD), Raman spectroscopy diffraction techniques, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Hall measurement of the seed layer that was produced by the AIC technique and poly-Si films on seed layer that were deposited by HWCVD. For analysis of each layer, the poly-Si film have been used to detect the crystallization and preferred (111), (220) and (311) orientation by XRD and Raman spectroscopy diffraction techniques which be stronger than AIC-film. The microstructures of each film were observed by SEM and TEM. It was found that the AIC of grain was approximately 1 µm and the Si layers formed on seed layer of grain (1 µm in size) can be obtained. However, the lateral grain size of poly-Si (deposited on seed layer) was larger than the poly-Si films deposited directly on a glass substrate by HWCVD. Since the Si-atoms deposit in the orientation of seed layer, the poly-Si would be obtained. As a result, high crystalline fractions (91 and 95%) and high electron mobility (22 and 18 cm2/V-s) of poly-Si films were obtained by using a combination of HWCVD and AIC techniques.