POLYMER ORGANIC SEMICONDUCTORS AND THEIR DEVICES

Organic semiconducting (OSC) polymers has been used in wide range of applications, such as light-emitting diodes, solar cells, and transistors. Here, different aspects regarding the optimization of this layer are discussed in their respective devices. Firstly, synthetic methodology based on Suzuki coupling for generation of high molecular weight polymers is discussed using well-known fluorene-containing-polymers. Next, different molecular weight high-performance diketopyrrolopyrrole-based co-polymer was synthesized; their field-effect transistor performance and stability towards various environmental constraints was studied. Excellent performance thermal and ambient stability for this type of semiconductors was demonstrated. Degradation was only observed after 10 hours of light exposure in accelerated thermal stress. Lastly, to address current phase-separation problems in photovoltaic devices, a covalently linked, p-conjugated di-block co-oligomer were designed, synthesized, and achieved a power conversion efficiency of 1.2% in device applications, comparable to best values reported using similar material systems. Further, their impact on polymer blend film morphology was discussed.

Author dc:creator

• HU CHEN

• polymer semiconductor; organic photovoltaics; organic field-effect transistor; polymer synthesis; FET stability