Enhancement in performance of optoelectronic devices by optical-functional patterns

Abstract

In this study, nanoimprint lithography (NIL) and a direct printing technique were used to create optical-functional structures on the substrate of organic light emitting diodes (OLEDs) and alpha-Si solar cell devices in order to cause light scattering and enhance their efficiencies. NIL can fabricate nanoscale patterns with a simple process and relatively low costs. Apart from low cost, the NIL-based direct patterning process also has advantages such as high throughput and high resolution. In addition, it enables the fabrication of inorganic or organic-inorganic hybrid nano-patterns on various substrates and can therefore be applied to diverse electronic devices to enhance their performance. The performances of the optoelectronic devices were improved after the formation of the optical-functional structure. In case of a thin-film solar cell on patterned glass, its conversion efficiency was increased up to 39.1 %, while the conversion efficiency of a thin-film solar cell on a patterned metal layer was increased up to 12 %. In case of OLEDs, the current and power efficiencies of OLEDs on planarized patterns were enhanced by 32 and 49 %, respectively.