1,4,5,8-Naphthalene-tetracarboxylic-dianhydride (NTCDA) organic thin-him-tr
ansistors employed as humidity sensors exhibit higher performance level com
pared to NTCDA chemiresitors. In particular, the transistor on-current exhi
bits higher values and a larger dynamic range as well as a better reversibi
lity, compared to the response of an NTCDA resistor. On the basis of the FT
-IR spectra of NTCDA humid and anhydrous thin-films, a model for the NTCDA/
H2O system is proposed which eventually explains the variation of NTCDA thi
n-film-transistor parameters, while the device is exposed to changing water
vapor atmosphere. (C) 2001 Elsevier Science B.V. All rights reserved.