Semiconducting Polymers and Devices

One of the earliest observations of high eonductivity in sueh a material was in a form of poly(acetylene) by a Japanese team (Shirakawa and Ikeda 1971). Perhaps one should date the pursuit of semieondueting polymer deviees from that experiment. It soon became clear that conjugated polymers had a severe drawback most of them are extremely stable against potential solvents they cannot be forced 

By 1988, a number of devices such as a MOSFET transistor had been developed by the use of poly(acetylene) (Burroughes et al. 1988), but further advances in the following decade led to field-effect transistors and, most notably, to the exploitation of electroluminescence in polymer devices, mentioned in Friend s 1994 survey but much more fully described in a later, particularly clear paper (Friend et al. 1999). The polymeric light-emitting diodes (LEDs) described here consist in essence of a polymer film between two electrodes, one of them transparent, with careful control of the interfaces between polymer and electrodes (which are coated with appropriate films). PPV is the polymer of choice. 

The latest review of the status and prospects of polymer electronics (Samuel 2000), by a young physicist working in Durham University, England, goes at length into the possibilities on the horizon, including the use of copolymer chains with a series of blocks with distinct functions, and the possible use of dendrimer molecules 

Polymers have come a long way from parkesine, celluloid and bakelite they have become functional as well as structural materials. Indeed, they have become both at the same time one novel use for polymers depends upon precision micro-embossing of polymers, with precise pressure and temperature control, for replicating electronic chips containing microchannels for capillary electrophoresis and for microfluidics devices or micro-optical components. 

Bassett, D.C. (1981) Principles of Polymer Morphology (Cambridge University Press, Cambridge). 

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