The effects of moisture in low-voltage organic field-effect transistors gated with a hydrous solid electrolyte

Nikolai Kaihovirta*, Harri Aarnio, Carl Johan Wikman, Carl Eric Wilén, Ronald Österbacka

*Corresponding author for this work

Research output: Contribution to journalArticleScientificpeer-review

24 Citations (Scopus)

Abstract

The concept of using ion conducting membranes (50-150 JXm thick) for gating low-voltage (1 V) organic field-effect transistors (OFETs) is attractive due to its low-cost and large-area manufacturing capabilities. Furthermore, the membranes can be tailor-made to be ion conducting in any desired way or pattern. For the electrolyte gated OFETs in general, the key to low-voltage operation is the electrolyte "insulator" (the membrane) that provides a high effective capacitance due to ionic polarization within the insulator. Hydrous ion conducting membranes are easy to process and readily available. However, the role of the water in combination with the polymeric semiconductor has not yet been fully clarified. In this work electrical and optical techniques are utilized to carefully monitor the electrolyte/semiconductor interface in an ion conducting membrane based OFET. The main findings are that 1) moisture plays a major part in the transistor operation and careful control of both the ambient atmosphere and the potential differences between the electrodes are required for stable and consistent device behavior, 2) the obtained maximum effective capacitance (5 μFcm-2) of the membrane suggests that the electric double layer is distributed over a broad region within the polyelectrolyte, and 3) electromodulation spectroscopy combined with current-voltage characteristics provide a method to determine the threshold gate voltage from an electrostatic field-effect doping to a region of (irreversible) electrochemical perturbation of the polymeric semiconductor.

Original languageEnglish
Pages (from-to)2605-2610
Number of pages6
JournalAdvanced Functional Materials
Volume20
Issue number16
DOIs
Publication statusPublished - 23 Aug 2010
MoE publication typeA1 Journal article-refereed

Fingerprint Dive into the research topics of 'The effects of moisture in low-voltage organic field-effect transistors gated with a hydrous solid electrolyte'. Together they form a unique fingerprint.

Cite this