Content area
Full text
Received Aug 22, 2017; Revised Nov 24, 2017; Accepted Dec 10, 2017
This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
1. Introduction
Latest trends in the electronics industry are focused on looking for alternatives to inorganic semiconductors (based on silicon) by organic semiconductors in some applications, namely, transistors [1, 2], light-emitting diodes [3, 4], photovoltaic cells [5, 6], displays [7], sensors [8, 9], and even integrated circuits [1, 10]. These new devices use the same circuits and mechanical structures than inorganic devices, with the advantage of being easier to develop and setup by conventional chemical techniques. Standards describing the fabrication procedures of these organic devices already exist, and substrates and other raw materials for their fabrication are commercially available at low cost [11–13].
Development of these new electronic devices requires their electrical characterization by means of the appropriate equipment [14]. Devices used so far for this purpose are those traditionally used for the characterization of Si-based transistors, since the operation of organic transistors can be explained on the basis of the Si semiconductors theory, with a good approach. However, it is of great interest to develop devices that allow organic transistors to be specifically studied and that could contribute therefore to improve the understanding of their operation. Characterization of these new electronic devices is hindered by the very low electrical current they provide (around 10−6 A), with the further difficulty that they usually require high voltages (tens of volts). Moreover, commercial systems that fulfill these characteristics are very expensive.
This work aims at describing a measuring device that has been specifically designed to study organic transistors, using exclusively low-cost commercial components and a software that has been specially developed for this application. The device described here has great flexibility, since it can be used for different types of transistors. Finally, this module has been used to characterize an organic field effect transistor (OFET) based on TIPS-pentacene.
OFETs have attracted increasing attention in the past decades due to their potential application as sensor systems for the detection of chemical species [15]. OFETs show superior performance compared to resistor-type, amperometric, and potentiometric sensors, and...