Details

Autor(en) / Beteiligte

• Dehuff, N L
• Kettenring, E S
• Hong, D
• Chiang, H Q
• Wager, J F
• Hoffman, R L
• Park, C.-H
• Keszler, D A

Titel

Transparent thin-film transistors with zinc indium oxide channel layer

Ist Teil von

• Journal of applied physics, 2005-03, Vol.97 (6), p.064505-064505-5

Ort / Verlag

American Institute of Physics

Erscheinungsjahr

2005

Link zum Volltext

Quelle

AIP Journals Complete

Beschreibungen/Notizen

• High mobility, n -type transparent thin-film transistors (TTFTs) with a zinc indium oxide (ZIO) channel layer are reported. Such devices are highly transparent with ∼ 85 % optical transmission in the visible portion of the electromagnetic spectrum. ZIO TTFTs annealed at 600°C operate in depletion-mode with threshold voltages − 20 to − 10 V and turn-on voltages ∼ 3 V less than the threshold voltage. These devices have excellent drain current saturation, peak incremental channel mobilities of 45 - 55 cm 2 V − 1 s − 1 , drain current on-to-off ratios of ∼ 10 6 , and inverse subthreshold slopes of ∼ 0.8 V ∕ decade . In contrast, ZIO TTFTs annealed at 300°C typically operate in enhancement-mode with threshold voltages of 0 - 10 V and turn-on voltages 1 - 2 V less than the threshold voltage. These 300°C devices exhibit excellent drain-current saturation, peak incremental channel mobilities of 10 - 30 cm 2 V − 1 s − 1 , drain current on-to-off ratios of ∼ 10 6 , and inverse subthreshold slopes of ∼ 0.3 V ∕ decade . ZIO TTFTs with the channel layer deposited near room temperature are also demonstrated. X-ray diffraction analysis indicates the channel layers of ZIO TTFTs to be amorphous for annealing temperatures up to 500°C and polycrystalline at 600°C. Low temperature processed ZIO is an example of a class of high performance TTFT channel materials involving amorphous oxides composed of heavy-metal cations with ( n − 1 ) d 10 n s 0 ( n ⩾ 4 ) electronic configurations.