Light Trapping for Solar Cells

The textured microstructures and the photonic nanostructures for light trapping structures are discussed. The inverted pyramidal microstructures with and without the tips were fabricated, and their light trapping performances were measured by the reflectance spectroscopy and simulated by ray tracing method. It is found that there are more chances of light reflecting between the surfaces of the tips and the inverted pyramids. Four kinds of nanophotonic light trapping structures are simulated by the finite-difference time-domain method, and their optical transmissions and light trapping performances are calculated. The results show that mixing the dielectric and metallic nanoparticles or materials can have superior light trapping performances as comparing to using dielectric nanoparticles only or using metallic nanoparticles only. The other kinds of light trapping structures and their outlooks are also given.