3．Nanostructural control of Side-Chain Liquid-Crystalline Polymers with the High Hole Mobility

Silicon-based electronics is the most important technology in the modern society.
However, the electronics based on soft materials such as liquid crystals and polymers will be more
significant in this century.
We investigate the electronic function of soft materials including liquid crystals, polymers, and
gels. We have already developed liquid-crystalline semiconductors, cholesteric semiconductors
with photonic structures, liquid-crystalline flexible field effect transistors, and electrochromic
liquid crystals. In future, soft semiconductors 'to feel' will be realized.
For this objective, we will challenge structural control on the scale of nm for the functionalization
of the materials. Utilizing nanophase separation and self-organization in soft materials, we will
create new electronic materials with soft electronic systems.

* A new research theme starting in the Kagawa University since 2010

LC semiconductors which exhibit the high solubilities
and the low transition temperatures are designed.
Oligosiloxane side chains also promote the formation
of soft nanostrucures.

6. Liquid-Crystalline Semiconductors Bearing Oligosiloxane Side Chains

1．Liquid-Crystalline Semiconductors and the Carrier Transport in the Mesophase

Liquid crystals works as organic semiconductors!
Molecular alignment and stacking structure create
new dynamic electronic functions.

FETs are fabricated using LC semiconductors!
Moreover, the devices can be flexible!

＊　This research was mainly carried out with Dr. F. Zhang and Prof. N. Tamaoki
in Nanotechnology Research Institute of AIST (Tsukuba) during 2006-2008.

Nanosegregation between the liquid like
polymer backbones and rigid mesogenic
groups promotes hole transport!

＊ This research was mainly carried out with Prof. T. Kato and Miss A. Matsui
in the University of Tokyo during 2007-2010.

＊ This research was carried out with Prof. Kato and Dr. S. Yazaki
in the University of Tokyo during 2007-2010.

5.　Cholesteric Semiconductors with the Photonic Bang Structures

Chiral oligothiophene derivatives form helical
structures to form photonic bands. They
transport holes and emit circularly polarized light.

＊ This research was carried out with Prof. N. Tamaoki
in Nanotechnology Research Institute of AIST (Tsukuba) during 2006-2008.

Japanese home page is here.

4．Electrochromic Liquid Crystals bearing π-Conjugated and Ionic Moieties

＊　This research was mainly carried out with Prof. J. Hanna
in Tokyo Institute of Technology during 1994‐2005.

2．Application of Liquid-Crystalline Semiconductors to Flexible Field-Effect Transistors

DC bias application causes bulk
electrochromism in the nanosegregated
liquid crystal phase!