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2005, 11

M. Kandouci, S. Mottet, C. Kandouci

A model for the conduction in polycrystalline silicon thin film transistors

language: English

received 29.11.2004, published 29.04.2005

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The aim of this paper is the analysis, prediction and optimisation of polysilicon thin film transistors (TFTs) in both « on » and « off » states. We have established a physical model which accounts for the grain, the grain surface and grain boundaries. The conduction mechanisms and the exchange between electron and hole populations are explicitly considered. Field effects are included through the influence of carrier velocity saturation, impact ionisation and interband tunnel effect. A fair agreement between experimental characteristics and simulated results is obtained, and the simulations allow a good insight into the main mechanisms controlling the TFT operation modes.

Keywords: Polysilicon, dangling bonds, band tail states, TFT, simulation, generation-recombination, impact ionisation, interband tunnel effect

16 pages, 12 figures

Сitation: M. Kandouci, S. Mottet, C. Kandouci. A model for the conduction in polycrystalline silicon thin film transistors. Electronic Journal “Technical Acoustics”,, 2005, 11.


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Malika Kandouci received the B.S. and the M.S. degrees in electronics from Sidi Bel Abbès Institute of Physics, in 1982 and 1986, respectively. She received her PhD degree in physics of semiconductors in 1993 from Rennes I University of France. From 1994 to 1997 she worked at CNET (Center National of Studies on Telecommunication) Lannion in KEOPS project. Presently she is professor at Sidi Bel-Abbes University, Algeria.

e-mail: maikand04(at)

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S. Mottet an Ingineer of ENSMA in 1971, PhD in 1977. From 1981 to 1998 he was charged of modeling at ICM division of CNET (Center National of Studies on Telecommunication) Lannion, France. Since 1990 he is currently professor at ENSSAT (Ecole Nationale Superieure des Sciences Appliquees et de Technologie), Lannion, France.


C. Kandouci was born in 1960 in Saida, Algeria. He received his BS degree in electrical engineering from the Mechanical Engineering Institute of The University of Sciences and Technology of Oran (USTO) in 1985 and the PhD degree from the polytechnic school of Gdansk, Poland in 1990. Since 1990 he is teaching at The University of sciences and Technology of Oran (USTO), Algeria.