Polysilicon thin-film transistors with channel length and width comparable to or smaller than the grain size of the thin film

Author

Yamauchi, Noriyoshi ; Hajjar, Jean-Jacques J. ; Reif, Rafael

Author_Institution

Dept. of Electr. Eng. & Comput. Sci., MIT, Cambridge, MA, USA

Volume

38

Issue

1

fYear

1991

fDate

1/1/1991 12:00:00 AM

Firstpage

55

Lastpage

60

Abstract

Poly-Si thin-film transistors (TFTs) with channel dimensions (width W, and length L) comparable to or smaller than the grain size of the poly-Si film were fabricated and characterized. The grain size of the poly-Si film was enhanced by Si ion implantation followed by a low-temperature anneal and was typically 1 to 3 μm in diameter. A remarkable improvement was observed in the device characteristics as the channel dimensions decreased to W=L =2 μm. On the other hand, TFTs with submicrometer channel dimensions were characterized by an extremely abrupt switching in their I_D versus V_GS characteristics. The improvement was attributed to a reduction in the effect of the grain boundaries and to the effect of the device´s floating body

Keywords

carrier mobility; elemental semiconductors; grain boundaries; grain size; silicon; thin film transistors; 1 to 3 micron; I-V characteristics; Si ion implantation; Si-SiO₂; channel length; channel width; extremely abrupt switching; field effect mobility; floating body; grain boundaries; low-temperature anneal; polysilicon TFTs; submicrometer channel dimensions; thin film grain size; thin-film transistors; Active matrix technology; Annealing; Fabrication; Glass; Grain boundaries; Grain size; Semiconductor films; Substrates; Temperature; Thin film transistors;

fLanguage

English

Journal_Title

Electron Devices, IEEE Transactions on

Publisher

ieee

ISSN

0018-9383

Type

jour

DOI

10.1109/16.65736

Filename

65736