Novel Symmetric Vertical-Channel Ni-Salicided Poly-Si Thin-Film Transistors With High on/off-Current Ratio

Author

Wu, Yi-Hong ; Kuo, Po-Yi ; Lu, Yi-Hsien ; Chen, Yi-Hsuan ; Chao, Tien-Sheng

Author_Institution

Dept. of Electrophys., Nat. Chiao Tung Univ., Hsinchu, Taiwan

Volume

31

Issue

11

fYear

2010

Firstpage

1233

Lastpage

1235

Abstract

We have successfully fabricated the symmetric vertical-channel Ni-salicided polycrystalline silicon thin-film transistors (VSA-TFTs) for the first time. The transfer characteristics of VSA-TFTs show a sharp turning between subthreshold and on state. The off -state currents can be improved by a modified overetching of oxide, equivalent dual-gate structure, and n⁺ floating-region length. The on-state currents can be enhanced by Ni-salicidation. The VSA-TFTs display a good subthreshold swing of 220 mV/dec, steep mobility increase (field-effect mobility of 76 cm²/V·s), and large on/off-current ratio of more than 10⁹ (I_OFF = 4 × 10^-14, I_ON = 7 × 10^-5, and W_mask/L_mask = 10 μm/3 μm).

Keywords

elemental semiconductors; etching; silicon; thin film transistors; VSA-TFT; equivalent dual-gate structure; field-effect mobility; floating-region length; off -state current; on-state current; overetching; steep mobility; subthreshold swing; symmetric vertical-channel Ni-salicided polycrystalline silicon thin-film transistor; transfer characteristics; Leakage current; Logic gates; Resistance; Silicon; Thin film transistors; Ni-salicided; polycrystalline silicon thin-film transistors (poly-Si TFTs); symmetric S/D; vertical channel;

fLanguage

English

Journal_Title

Electron Device Letters, IEEE

Publisher

ieee

ISSN

0741-3106

Type

jour

DOI

10.1109/LED.2010.2061215

Filename

5559329