Inexpensive graded-index antireflective surfaces for silicon-based optoelectronic devices

Abstract

Polymer films patterned using a self-assembled photonic crystal resulted in feature sizes of the order of a few hundred nanometers (nm) and pattern depths of a few tens of nm over large areas of square centimeters. The depth of patterning and the resulting graded refractive index profile led to angle- and wavelength-independent antireflection from the patterned films. The extent of antireflection and the improvement in efficiency when these patterned films are laminated on a bare solar cell are found to increase when the depth of patterning is increased. Numerical analysis in our work uses the rigorous coupled wave method.