Effects of Channel Width and NH[sub 3] Plasma Passivation on Electrical Characteristics of Polysilicon Thin-Film Transistors by Pattern-Dependent Metal-Induced Lateral Crystallization

Yung-Chun Wu, Ting-Chang Chang, Cheng-Wei Chou, Yuan-Chun Wu, Po-Tsun Liu, Chun-Hao Tu, Wen-Jun Huang, Jen-Chung Lou, Chun-Yen Chang
2005 Journal of the Electrochemical Society  
This work studied the effects of channel width and NH 3 plasma passivation on the electrical characteristics of a series of pattern-dependent metal-induced lateral crystallization ͑PDMILC͒ polysilicon thin-film transistors ͑poly-Si TFTs͒. The performance of PDMILC TFTs improves as each channel width decreasing. Further, PDMILC TFTs with NH 3 plasma passivation outperforms without such passivation, resulting from the effective hydrogen passivation of the grain-boundary dangling bonds, and the
more » ... g bonds, and the pile-up of nitrogen at the SiO2/poly-Si interface. In particular, the electrical characteristics of a nanoscale TFT with ten 67 nm wide split channels ͑M10͒ are superior to those of other TFTs. The former includes a higher field effect mobility of 84.63 cm 2 /V s, a higher ON/OFF current ratio ͑Ͼ10 6 ͒, a steeper subthreshold slope ͑SS͒ of 230 mV/decade, and an absence of drain-induced barrier lowering ͑DIBL͒. These findings originate from the fact that the active channels of the M10 TFT have exhibit the most poly-Si grain enhanced to reduce the grain boundary defects and the best NH 3 plasma passivation. Both effects can reduce the number of defects at grain boundaries of poly-Si in active regions for high performances.
doi:10.1149/1.1931473 fatcat:bhwflytucjgzhc3c575iihw6ge