Silicon solar cells for use at high solar concentration

Silicon photovoltaic p+nn+solar cells have been developed for use in solar collectors which concentrates the solar illumination 250 to 350 times. The cell efficiency of these layered back-contact cells at a solar concentration of 280 suns (28 watts/cm2) is 15.5 percent. The thick base layer to achieve good quantum efficiency in the violet, the long minority carrier lifetime, the optimized grid structure, and two layer antireflection coating are all combined to produce an efficient solar cell at high solar concentration.