In:
Japanese Journal of Applied Physics, IOP Publishing, Vol. 49, No. 3S ( 2010-03-01), p. 03CB02-
Abstract:
In this study, we analyzed the temperature-dependent characteristics of amorphous indium–gallium–zinc-oxide (a-IGZO) thin-film transistors (TFTs). We observed that a-IGZO TFTs obey the Meyer–Neldel rule (MN rule) at low gate-to-source voltage ( V GS ) and the inverse MN rule at high V GS , both of which can be explained by the statistical shift of Fermi level and electrostatic potential. Large Fermi level movement for small V GS change and the inverse MN rule, which are hardly observed for conventional amorphous TFTs, indicate that there is a very low density of state (DOS) in the sub-bandgap region for a-IGZO TFTs and the performance of TFTs is not affected by contact characteristics, respectively. By using the field-effect method and considering surface band bending, we extracted the DOS in the sub-bandgap region, the distribution of which is clearly distinguished by deep and tail states. The calculated parameters for tail and deep states were N ta = 3.5 ×10 17 cm -3 eV -1 , E ta = 0.18 eV, N da = 1.6×10 16 cm -3 eV -1 , and σ da = 0.21 eV.
Type of Medium:
Online Resource
ISSN:
0021-4922
,
1347-4065
DOI:
10.1143/JJAP.49.03CB02
Language:
Unknown
Publisher:
IOP Publishing
Publication Date:
2010
detail.hit.zdb_id:
218223-3
detail.hit.zdb_id:
797294-5
detail.hit.zdb_id:
2006801-3
detail.hit.zdb_id:
797295-7
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