Page 116 - Organic Electronics in Sensors and Biotechnology

CHAPTER 3

Strain and Pressure

Sensors Based on

Organic Field-Effect

Transistors

Ileana Manunza and Annalisa Bonfiglio
Department of Electrical and Electronic Engineering,
University of Cagliari, Italy, and
INFM-CNR S3 Centre for nanoStructures and
bioSystems at Surfaces, Modena, Italy

3.1 Introduction
Research in biomedicine and engineering during the last years has
led to a remarkable interest in sensor technologies. For a broad range
of sensing applications there is a large demand for small, portable,
and inexpensive sensors. Silicon technology is not suitable for manu-
facturing low-cost large-area sensor devices that are preferably light,
flexible, and even disposable (for some biomedical applications). Its
inherent high-temperature fabrication processes make it very diffi-
cult to use inexpensive flexible substrate materials, resulting in high
fabrication costs. Organic semiconductors have been studied so far
mainly for their exceptional combination of electrical conductivity,
mechanical flexibility, and, last but not least, low cost of deposition
and patterning techniques. On the other hand, several drawbacks
still affect these materials: among them, low carrier mobility that
severely limits the possibility of applications in electronic circuits.
Therefore, to fully exploit the great potential of these materials, it is
advisable to focus on those applications where high performances in

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