The Study of Laser Crystalliztion Method on Tri-gated Poly-Si Nanowire Thin Film Transistors

• Main Authors: Ruei-sheng Hung, 洪瑞生
• Other Authors: Tsung-Kuei Kang
• Format: Others
• Language: zh-TW
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/93947674394194323812

碩士 === 逢甲大學 === 電子工程所 === 98 === Poly-Si thin-film transistors (TFTs) have been widely used as switching elements in active matrix display. For applications on system-on-pannel (SOP) and three-dimension integrated circuits (3-D ICs)，further improvements of device performance are required. The mobility is one of the most important electrical characteristic in poly-Si TFTs, which is profoundly dependent on the grain sizes within channel region. The use of sequential lateral solidification (SLS) crystallization is the approach to enlarge the grain size. In order to enhance transistors performance, we will continue to reduce device size. There are some undesired short-channel effects in conventional scaled poly-Si TFTs such as threshold voltage roll-off, drain-induced barrier lowering (DIBL). We proposed tri-gated poly-Si TFTs with multiple nanowire channels (MNC) which has better gate controllability to reduce DIBL. Tri-gated poly-Si TFTs with multiple nanowire channels has better performances. We also study positive bias stress(PBS)、negative bias stress (NBS) on the tri-gated poly-Si TFT with multiple nanowire channels (MNC). Tri-gated MNC TFTs exhibit excellent electrical performance as compared to convential planar(CP) TFT. Tri-gated MNC-TFTs demonstrate lower Vt,smaller DIBL, lower leakage current, higher on current, higher on/off ratio, and higher mobility. Tri-gated MNC TFTs induces serious damages due to electrochemical reaction at SiO2/Si interface under NBS.