Nano-texturing of Transparent Polymers with Plasma Etching: Tailoring Topography for a Low Reflectivity Rosa Di Mundo,* Mariagrazia Troia, Fabio Palumbo, Massimo Trotta, Riccardo d’Agostino 1. Introduction Transparent and colorless surfaces with low reflective or antireflective (AR) behavior are of great interest in many applications and research fields: they can minimize the reflection of optical components and the amount of radiation lost caused by the total internal reflection in light-emitting diodes (LEDs), improve the efficiency of solar cells through increased light-coupling, or can be applied to car windshields and building glass panes, just to name a few. Transparent polymers, in particular polycarbonate Full Paper R. Di Mundo, M. Troia, R. d’Agostino Department of Chemistry, University of Bari, Bari, Italy E-mail: rosadimundo@chimica.uniba.it F. Palumbo, R. d’Agostino Institute for Inorganic Methodologies and Plasmas (IMIP)-CNR, Bari, Italy M. Trotta Institute for Chemical-Physical Processes (IPCF)-CNR, Bari, Italy R. d’Agostino Plasma Solution Srl, Spin-off of the University of Bari, Bari, Italy The reflectivity of transparent polymers can be reduced with a proper nanotextured layer on the surface according to the ‘‘moth eye’’ effect. Plasma etching has been proved to be a reliable method to generate self-organized nanostructures on the surface of various polymers. In the present work this method, directly carried out in one step, has been tested on poly- carbonate for application as low reflective transparent material. CF 4 and O 2 fed plasma processes have been compared at different treatment time. Chemical (X-ray photoelectron spectroscopy), morphological (scanning electron microscopy), and optical (diffuse and specular reflectance, normal and grazing incidence) fea- tures have been evaluated. Results indicate that the CF 4 -to-O 2 feed ratio significantly affects shape and distribution of the generated structures. O 2 plasma, in particular, leads to taller structures with wire-like aspect and more homogeneous distribution, which are more effective in reducing reflectance with a broadband character (visible and near-infrared). Treatment duration, which instead affect mainly the dimension scale of the structures, must be tailored in order to control diffuse component of reflectance. Plasma Process. Polym. 2012, 9, 947–954 ß 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim wileyonlinelibrary.com DOI: 10.1002/ppap.201200041 947