Title :
Fully printed organic thin film transistors (OTFT) based flexible humidity sensors
Author :
Reddy, Avuthu S. G. ; Narakathu, Binu B. ; Eshkeiti, Ali ; Bazuin, Bradley J. ; Joyce, Margaret ; Atashbar, Massood Z.
Author_Institution :
Dept. of Electr. & Comput. Eng., Western Michigan Univ., Kalamazoo, MI, USA
Abstract :
A flexible fully printed organic thin film transistor (OTFT) was successfully fabricated and employed as a humidity sensor. The bottom gated OTFT, with width to length ratio (w/l) ratio of 26, was printed on a flexible poly ethylene terephthalate (PET) substrate. Conductive gate and dielectric layers were printed using gravure printing technique. Source and drain electrodes were deposited by means of screen printing. An active layer of pentacene, a humidity sensitive material, was deposited using inkjet printing. The current-voltage characteristics of the fully printed device were studied from 25% RH to 90% RH. A percentage change of 2000 % at 90% RH, in the drain current (ID), was registered when compared to the ID at 25% RH. The response of the fully printed sensor towards relative humidity was studied and is reported in this paper.
Keywords :
electrodes; flexible electronics; humidity sensors; ink jet printing; thin film transistors; bottom gated OTFT; conductive gate layers; current-voltage characteristics; dielectric layers; drain current; drain electrodes; flexible fully printed organic thin film transistor; flexible humidity sensors; flexible polyethylene terephthalate substrate; gravure printing technique; inkjet printing; pentacene; relative humidity; screen printing; source electrodes; Electrodes; Humidity; Logic gates; Organic thin film transistors; Printing; Sensors;
Conference_Titel :
SENSORS, 2013 IEEE
Conference_Location :
Baltimore, MD
DOI :
10.1109/ICSENS.2013.6688309
