Title :
Super thin-film transistor with SOI CMOS performance formed by a novel grain enhancement method
Author :
Wang, Hongmei ; Chan, Mansun ; Jagar, Singh ; Poon, Vincent M C ; Qin, Ming ; Wang, Yangyuan ; Ko, Ping K.
Author_Institution :
Dept. of Electr. & Electron. Eng., Hong Kong Univ. of Sci. & Technol., Kowloon, Hong Kong
fDate :
8/1/2000 12:00:00 AM
Abstract :
High performance super TFTs with different channel widths and lengths, formed by a novel grain enhancement method, are reported. High temperature annealing has been utilized to enhance the polysilicon grain and improve the quality of silicon crystal after low temperature MILC treatment on amorphous silicon. With device scaling, it is possible to fabricate the entire transistor on a single grain, thus giving the performance of single crystal SOI MOSFET. The effects of grain boundaries on device performance have been studied, indicating the existence of extra leakage current paths caused by the grain boundaries traversing the channel, which induced subthreshold hump and early punchthrough of wide devices. The probability for the channel region of a TFT to cover multiple grains decreases significantly when the device is scaled down, resulting in better device performance and higher uniformity
Keywords :
MOS integrated circuits; VLSI; annealing; grain refinement; leakage currents; thin film transistors; SOI CMOS performance; Si; channel widths; device performance; device scaling; early punchthrough; grain boundaries; grain enhancement method; high temperature annealing; leakage current paths; low temperature MILC treatment; polysilicon grain; subthreshold hump; super TFTs; Amorphous silicon; Annealing; CMOS technology; Crystallization; Grain boundaries; Grain size; Integrated circuit technology; MOSFET circuits; Temperature; Thin film transistors;
Journal_Title :
Electron Devices, IEEE Transactions on
