Light trapping enhancement in thin silicon solar cells using photonic crystals

Recent developments in light trapping designs based on photonic crystal structures are presented. Design structures that take advantage of the photonic stop-bands in specially engineered photonic crystal materials are described. To this end, the new materials allow for the propagation of normally incident light while disallowing the transmission of obliquely incident light waves. Hence, an angular selective light filter is formed that regulates the passage of light in and out of the solar cell structure. When combined with diffraction grating structures, the angular light filter provides a new type of light trap that differs from traditional geometric optical designs, such as texturing. This paper explores the science and possibilities afforded by the new photonic crystal enhanced solar cell.