Our group is engaged in the development of next-generation “Flexible electronics & Photonics” taking full advantages of high mechanical flexibility and electrical performances that organic materials inherently possess. Utilizing key technologies of functional material-based electronic and photonic devices, our group is aiming for creating new sciences of wide range from information-communication technologies (ICT) to the fields of bio-medical-welfare, and demonstrating to exhibit the usefulness of the devices on the wide range of social life.
Specifically, in addition to the excellent electrical and mechanical characteristics of organic materials, we are carrying out researches focusing on material science, device physics, and applied physic of flexible electronics and photonics manufacturing with self-organization phenomena (Organic supramolecular structure) and low-energy processes on organic materials.
Furthermore, the technical developments widely-ranging from organic nano-molecule layering technique, organic semiconductor/insulator interface-control technique, precise technique of physical properties of organic molecules and its analysis technique, and organic TFT-based circuit design technique have been realized for highly-integrated organic circuits.
So far, we have successfully developed the key technologies for high-performance flexible organic transistors [Nature Materials 9 (2010) 1015, Science 326 (2009) 1516, Nature Materials 6 (2007) 413] and realized the ultimate flexible electronics and stretchable electronics with excellent mechanical durability [Nature 499 (2013) 458), Nature Materials 8 (2009) 494, Science 321 (2008) 1468], and exhibited the feasibility and the usability of the electronic devices, for the first time.
Not only electronic devices, we have realized 1µ-m-thick organic light-emitting diodes (OLED) with conjugated polymers [Nature Photonics 7 (2013) 811] and organic solar cells, photodiodes (OPV) with bulk-hetero structure [Nature Communications 3 (2012) 770]. Taking advantages of ultra-thin organic transistors, organic LEDs, and organic PDs, we have created the new class of electronics, that is “Imperceptible electronics” for next-generation human/machine interfaces. This technology will open up new applications toward social implementation including the fields of bio, medical, and welfare.
Applied researches described above have been supported by state of the art material science, formation technology of fine-structures, and nano-structure and analysis technique. Especially, we have analysis method for single-molecular (1~2 nm) using synchrotron orbit radiation, X-ray photoemission spectroscopy (XPS), X-ray diffraction, and nano-space control technique [Nature Communications 3 (2012) 723].
Moreover, for attaining new process technologies, which enable us to control morphologies of surfaces and interfaces at nanoscale, we have studied the mechanism of the morphological evolution of surfaces and interfaces during various nonequilibrium processes such as crystal growth and thin film growth. Through observations with scanning tunneling microscopy, atomic force microscopy, etc., and model analysis, we investigate the behaviors of atoms and molecules at surfaces and interfaces.