Organic materials have long
been considered as insulators due to their poor optoelectronic properties.
Until very recently, they have been mostly utilized in non-electronic
applications such as packaging, textile, and manufacturing due to their
advantageous mechanical and physical properties over metals and ceramics.
Today, It is almost impossible to find an aspect of our lives that is not
affected by organics. The idea of using organic materials in microelectronics
was first demonstrated by three Nobel laurates (2000-Nobel Prize in Chemistry),
Hideki Shirakawa, Alan J. Heeger, and Alan G MacDiarmid, in the mid 1970s. The
discovery was based on a simple experiment of doping polyacetylene with iodine,
which resulted in a tremendeous increase in electrical conductivity (108-fold),
making it close to those of metals. Following these initial experiments,
functional organic materials have attracted significant attention over the last
three decades as electro-active materials for the development of printable and
flexible electronic devices such as organic thin-film transistors (OTFTs),
light-emitting diodes (OLEDs), light-emitting transistors (OLETs), and
photovoltaic cells (OPVs). Owing to their unique features over traditional
inorganic materials, they are envisioned as essential components for several
next-generation optoelectronic applications including low-power flexible
displays/electronic papers, wearable electronics, printable RFID tags/sensors,
and flexible solar panels.