Dr Deepak Venkateshvaran: "Molecular arrangement and nanomechanical properties of polymer thin films for organic electronics"
Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, CB3 0HE, U.K.
During the last three decades, research on organic semiconductors has primarily focused on their optical, electronic, and spin-based properties. [1, 2, 3] These studies have documented a wealth of scientific knowledge upon which a commercial ecosystem around flexible electronic circuits, solar energy harvesters and implantable bioelectronics has been built. The macroscopic mechanical flexibility of organic semiconductors is well known, and often taken for granted. Macroscopic flexibility remains a unique selling point for organic semiconductor technology and underpins the development of applications such as flexible displays and bendable thermoelectric devices that are also gradually becoming mainstream.
In the last decade, the development of high precision atomic force microscopes has made it possible to quantify the mechanical properties of organic polymers on the scale of a few of polymer chains. In tandem, techniques such as higher eigen mode imaging make it possible to visualise molecular ordering on the nanoscale under ambient conditions with ease. These techniques in tandem allow one to draw a correlation between molecular ordering and the stiffness that such ordering leads to. In this talk, new results on such an interrelation between molecular organisation and nanomechanical properties in a high-performance polymer used for organic electronics will be shown.  Such a nanomechanical characterisation of organic semiconductors is the first step towards their deployment in new electromechanical devices in which their nanomechanical properties can be electronically controlled. 
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