Nanostructured dielectric layer - A new approach to design nanostructured solar cells

Nanostructures have been widely used in solar cells due to their extraordinary optical management properties. However, due to the poor junction quality and large surface recombination velocity, typical nanostructured solar cells are not efficient. Here we demonstrate a new approach to design and fabricate whole-wafer nanostructures on dielectric layer for solar cell application. The design, simulation, fabrication and characterization of nanostructured dielectric layer silicon solar cells are presented. The optical simulation results illustrate that the periodic nanostructure array on dielectric materials suppresses the reflection and enhances the absorption over a wide spectral range. Reflection measurements show that reflection can be suppressed below 10% for a wide range of solar spectrum and incident angle. The current density-voltage (J-V) characterization shows that the short circuit current is improved by 44%. Our results suggest this nanostructured dielectric layer has the potential to significantly improve solar cell performance and avoid typical problems of defects and surface recombination for nanostructured solar cells, thus providing a new pathway towards realizing high-efficiency and low-cost solar cells.