Impact of structure symmetry on light trapping properties of periodic nanostructures: A systematic discussion and quantification

摘要: Submicron periodic nanostructures have great potential for light trapping in ultra-thin silicon solar cells. In addition to period, aspect ratio, and structure geometry, the symmetry of also has an impact on their properties. It been generally agreed that breaking such structures can enhance trapping. However, quantitative relation asymmetry is still open question. this work, we suggest a method quantify using inverted nanopyramids (PiNPs) as case study. Different degree introduced into by changing cross section baseline PiNPs hexagon, octagon, or circle skewing different degree. We then present systematic discussion broken absorption context The results demonstrate effects increase with asymmetry. For investigated configurations, could improve absorbed photocurrent density up 3 mA/cm2. propose explanations enhanced due from perspective diffraction near-field enhancement.