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Localized Tail States and Electron Mobility in Amorphous ZnON Thin Film Transistors.

ABSTRACT: The density of localized tail states in amorphous ZnON (a-ZnON) thin film transistors (TFTs) is deduced from the measured current-voltage characteristics. The extracted values of tail state density at the conduction band minima (N(tc)) and its characteristic energy (kT(t)) are about 2?×?10(20)?cm(-3)eV(-1) and 29?meV, respectively, suggesting trap-limited conduction prevails at room temperature. Based on trap-limited conduction theory where these tail state parameters are considered, electron mobility is accurately retrieved using a self-consistent extraction method along with the scaling factor '1/(??+?1)' associated with trapping events at the localized tail states. Additionally, it is found that defects, e.g. oxygen and/or nitrogen vacancies, can be ionized under illumination with hv???E(g), leading to very mild persistent photoconductivity (PPC) in a-ZnON TFTs.

SUBMITTER: Lee S

PROVIDER: S-EPMC4548246 | biostudies-literature | 2015 Aug

REPOSITORIES: biostudies-literature

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Localized Tail States and Electron Mobility in Amorphous ZnON Thin Film Transistors.

Lee Sungsik S Nathan Arokia A Ye Yan Y Guo Yuzheng Y Robertson John J

Scientific reports 20150825

The density of localized tail states in amorphous ZnON (a-ZnON) thin film transistors (TFTs) is deduced from the measured current-voltage characteristics. The extracted values of tail state density at the conduction band minima (N(tc)) and its characteristic energy (kT(t)) are about 2 × 10(20) cm(-3)eV(-1) and 29 meV, respectively, suggesting trap-limited conduction prevails at room temperature. Based on trap-limited conduction theory where these tail state parameters are considered, electron mo ...[more]

PMID: 26304606

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