Device-ready doped polymer semiconductors

Electronic and optoelectronic devices made from organic polymers can be produced via solution processing, which is inexpensive, offers a high degree of design control and is especially suitable for producing flexible materials. An outstanding challenge is to make good ‘ohmic’ electrical contact with metal connections. This requires polymers with high charge doping content, but it is difficult to obtain highly doped polymer films from solution that retain their doping charges and are sufficiently stable. Peter Ho and colleagues present a general approach to produce polymers with stable, high doping content, by including a self-compensation mechanism that involves covalently bonded counter ions to block the migration of dopants. They apply this to a range of polymers and demonstrate devices including high-performance light-emitting diodes and ambipolar field-effect transistors.