Improvement of Subthreshold Characteristics of Dopingless Tunnel FET Using Hetero Gate Dielectric Material: Analytical Modeling and Simulation

AbstractIn the quest for ever smaller transistor dimensions, the well-known and reliable SiO2 gate dielectric material needs to be replaced by alternatives whith higher dielectric constants in order to reduce the gate leakage. Candidate materials are metal oxides such as HfO2. Themost promising deposition techniques, next to Physical Vapor Deposition, appear to be ALCVD and MOCVD. In this paper, we compare the most important characteristics of layers from both proces techniques and assess their relevance to gate stack applications: density, crystallisation, impurities, growth mechanism, interfacial layers, dielectric constant, mobility. Although we find some minor differences, layers from both techniques mostly show striking similarities in many aspects, both positive and negative.

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High-Mobility 6,13-Bis(triisopropylsilylethynyl) Pentacene Transistors Using Solution-Processed Polysilsesquioxane Gate Dielectric Layers

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2016.12293 ◽

2016 ◽

Vol 16 (4) ◽

pp. 3273-3276 ◽

Cited By ~ 3

Author(s):

Yu Matsuda ◽

Yoshio Nakahara ◽

Daisuke Michiura ◽

Kazuyuki Uno ◽

Ichiro Tanaka

Keyword(s):

Thin Film Transistors ◽

Gate Dielectric ◽

Dielectric Material ◽

Low Cost ◽

High Mobility ◽

Hole Mobility ◽

Plastic Substrates ◽

Active Layers ◽

Dielectric Layers ◽

Gate Dielectric Material

Polysilsesquioxane (PSQ) is a low-temperature curable polymer that is compatible with low-cost plastic substrates. We cured PSQ gate dielectric layers by irradiation with ultraviolet light at ~60 °C, and used them for 6,13-bis(triisopropylsilylethynyl) pentacene (TIPS-pentacene) thin film transistors (TFTs). The fabricated TFTs have shown the maximum and average hole mobility of 1.3 and 0.78±0.3 cm2V−1s−1, which are comparable to those of the previously reported transistors using singlecrystalline TIPS-pentacene micro-ribbons for their active layers and thermally oxidized SiO2 for their gate dielectric layers. It is therefore demonstrated that PSQ is a promising polymer gate dielectric material for low-cost organic TFTs.

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Investigation of Ultraviolet Light Curable Polysilsesquioxane Gate Dielectric Layers for Pentacene Thin Film Transistors

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2016.12292 ◽

2016 ◽

Vol 16 (4) ◽

pp. 3327-3331 ◽

Cited By ~ 2

Author(s):

Hideto Shibao ◽

Yoshio Nakahara ◽

Kazuyuki Uno ◽

Ichiro Tanaka

Keyword(s):

Thin Film ◽

Thin Film Transistors ◽

Carrier Mobility ◽

Gate Dielectric ◽

Dielectric Material ◽

Uv Light ◽

Limiting Factor ◽

Dielectric Layers ◽

Linker Molecules ◽

Gate Dielectric Material

Polysilsesquioxane (PSQ) comprising 3-methacryloxypropyl groups was investigated as an ultraviolet (UV)-light curable gate dielectric material for pentacene thin film transistors (TFTs). The surface of UV-light cured PSQ films was smoother than that of thermally cured ones, and the pentacene layers deposited on the UV-light cured PSQ films consisted of larger grains. However, carrier mobility of the TFTs using the UV-light cured PSQ films was lower than that of the TFTs using the thermally cured ones. It was shown that the cross-linker molecules, which were only added to the UV-light cured PSQ films, worked as a major mobility-limiting factor for the TFTs.

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