TY - JOUR
T1 - Thickness-dependent threshold voltage in polycrystalline pentacene-based thin-film transistors
AU - Wang, Yu Wu
AU - Cheng, Horng Long
N1 - Funding Information:
The authors acknowledge partial financial support from the National Science Council, Taiwan, through Grant No. NSC 96-2221-E-018-021.
Copyright:
Copyright 2009 Elsevier B.V., All rights reserved.
PY - 2009/10
Y1 - 2009/10
N2 - We have studied the current-voltage characteristics and threshold voltage behaviors in polycrystalline pentacene-based organic thin-film transistors (OTFTs) with gold top-contact electrodes for different thickness of the pentacene films. The study uses a number of techniques to measure threshold voltage including: square-root method, constant-current method, maximum transconductance method and capacitance-voltage measurements. The results of our experiments suggest that the space-charge and trapping effects of the pentacene bulk film plays an important role in current-voltage characteristics. In the presence of trapping centers within the polycrystalline pentacene film, we have provided an analytical model explaining the effect of bulk traps on the thickness-dependent threshold voltage. Square-law of threshold voltage versus pentacene thickness in OTFTs was derived during our study providing consistent results with experimental data. Furthermore, using the square-law, we estimated trap density of about 1017 cm-3 in experimental pentacene films. The orders of magnitude in trap density of polycrystalline pentacene films are similar to the values found in other literature source.
AB - We have studied the current-voltage characteristics and threshold voltage behaviors in polycrystalline pentacene-based organic thin-film transistors (OTFTs) with gold top-contact electrodes for different thickness of the pentacene films. The study uses a number of techniques to measure threshold voltage including: square-root method, constant-current method, maximum transconductance method and capacitance-voltage measurements. The results of our experiments suggest that the space-charge and trapping effects of the pentacene bulk film plays an important role in current-voltage characteristics. In the presence of trapping centers within the polycrystalline pentacene film, we have provided an analytical model explaining the effect of bulk traps on the thickness-dependent threshold voltage. Square-law of threshold voltage versus pentacene thickness in OTFTs was derived during our study providing consistent results with experimental data. Furthermore, using the square-law, we estimated trap density of about 1017 cm-3 in experimental pentacene films. The orders of magnitude in trap density of polycrystalline pentacene films are similar to the values found in other literature source.
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U2 - 10.1016/j.sse.2009.05.003
DO - 10.1016/j.sse.2009.05.003
M3 - Article
AN - SCOPUS:68349128670
VL - 53
SP - 1107
EP - 1111
JO - Solid-State Electronics
JF - Solid-State Electronics
SN - 0038-1101
IS - 10
ER -