TY - JOUR
T1 - Light- and bias-induced effects in pentacene-based thin film phototransistors with a photocurable polymer dielectric
AU - Liguori, R.
AU - Sheets, W. C.
AU - Facchetti, A.
AU - Rubino, A.
N1 - Funding Information:
Support by SMARTAGS project ( PON02_00556_3420580 ) financed by the Ministero dell’Università e della Ricerca (MIUR) in the ambit of the National Operational Programme for Research and Competitiveness 2007-2013 is gratefully acknowledged.
Publisher Copyright:
© 2015 Elsevier B.V.
PY - 2016/1/1
Y1 - 2016/1/1
N2 - In this work, pentacene-based thin film phototransistors were fabricated with a photocurable polymer insulator and their electrical stability was monitored when the devices were exposed to light sources at different wavelengths. The magnitude of the photocurrent induced by illumination was found to be the result of two distinct factors: a direct photocurrent, related to electron-hole pair generation, and a current enhancement caused by a threshold voltage shift. The direction of threshold translation is attributed to the nature of trap states, specifically those located in the pentacene film near the interface with the polymer, and is affected by a measurement-induced effect, so that the photosensitivity can be modulated by a persistent gate bias during illumination. The equations for these two contributions were developed to study the light effects on material structure, the trapping process of electrons at the insulator-semiconductor interface and the photoconductive efficiency in the organic semiconductor.
AB - In this work, pentacene-based thin film phototransistors were fabricated with a photocurable polymer insulator and their electrical stability was monitored when the devices were exposed to light sources at different wavelengths. The magnitude of the photocurrent induced by illumination was found to be the result of two distinct factors: a direct photocurrent, related to electron-hole pair generation, and a current enhancement caused by a threshold voltage shift. The direction of threshold translation is attributed to the nature of trap states, specifically those located in the pentacene film near the interface with the polymer, and is affected by a measurement-induced effect, so that the photosensitivity can be modulated by a persistent gate bias during illumination. The equations for these two contributions were developed to study the light effects on material structure, the trapping process of electrons at the insulator-semiconductor interface and the photoconductive efficiency in the organic semiconductor.
KW - Bias stress
KW - Organic phototransistor
KW - Pentacene
KW - Thin film transistor
KW - Threshold voltage
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U2 - 10.1016/j.orgel.2015.10.029
DO - 10.1016/j.orgel.2015.10.029
M3 - Article
AN - SCOPUS:84946240215
SN - 1566-1199
VL - 28
SP - 147
EP - 154
JO - Organic Electronics: physics, materials, applications
JF - Organic Electronics: physics, materials, applications
ER -