Nanofeatured anti-reflective films manufactured using hot roller imprinting and self-assembly nanosphere lithography

Abstract

This paper details the continuous fabrication of nanofeatured anti-reflective films for solar cells, using hot roller imprinting and self-assembly nanosphere lithography. Polystyrene nanospheres of different sizes (471, 628, and 1200nm) were first self-assembled onto Silicon substrates by a spin coater. A thin layer of aluminum was then deposited onto the surface of nanosphere-patterned substrates, using the plasma sputtering technique. After electroforming, nickel–cobalt membranes containing nano-arrays of different sizes were obtained. The membranes were then attached to the surface of the metallic roller in a hot roller imprinting facility. The imprinting facility was used to replicate the nanofeatures onto 60μm thick polyethylene terephthalate (PET) films. The imprinted films were characterized using water contact angle measurement, a UV–vis spectrophotometer, atomic force microscope (AFM), and scanning electron microscope (SEM); the enhancement efficiency of the nanofeatured films for the solar cells was also measured by a solar simulator. The measured results suggested that the imprinted films could effectively reduce the reflectance and increase the conversion efficiency of solar cells.