Novel electrodes and active materials for optoelectronics and memory devices

Abstract

In optoelectronics, a competent alternate to the expensive and brittle indium-tin-oxide (ITO), is the need of the hour. This study is focused on developing an extremely simple, three step process of filling networked crackles formed in a dried colloidal layer, with a desired metal to produce metal in crackle pattern (MCP) based transparent conducting electrode (TCE). By design, TCE consists of a single metal micro/nanowire network with extremely smooth surface (roughness, ~ 9 nm) and seamless junctions over several tens of cm2 area on common substrates such as glass. This method allows fabricating TCE even on curved surfaces such as a quartz tube. The metal can be deposited either by physical methods or by solution processed method. MCPs with M as Au, Ag, Cu, Pd, Al, and Zn as well as of Au and Al over Cu have been prepared. The TCEs are high performing; a sheet resistance of ~ 2.4 ?/sq at ~ 90% (550 nm) transmittance has been achieved, AuCP/quartz showed high transmittance even in UV and IR regions. While MCP on polyethylene-terephalate (PET) produced a flexible and highly robust as well as chemically stable TCE.