Design of dielectric/metal/dielectric transparent electrodes for flexible electronics

Abstract

A flexible transparent electrode (FTE) is one of the most essential parts for the next generation of flexible optoelectronic devices, including solar cells, displays, and solid-state lighting devices. Although a lot of candidate materials for the FTE such as metallic nanowires, carbon nanotube, and graphene have been investigated, each material has fundamental limits as FTE applications, such as low transmittance (70% to 80%), high sheet resistance (>100 ohm/sq) and rough surface morphology. Dielectric/metal/dielectric (DMD) electrode structure is a promising candidate for next-generation flexible transparent electrodes. Compared with other transparent electrodes, DMD electrodes show best performance in terms of optical transparency, sheet resistance, and mechanical flexibility. In addition, it has been also reported that the device performances can be significantly enhanced by the microcavity effects with the DMD electrodes. We review the relevant principles and discusses recent progress in DMD electrodes. (C) 2012 Society of Photo-Optical Instrumentation Engineers (SPIE). [DOI: 10.1117/1.JPE.2.021215]