Crystalline silicon solar cells with high efficiency
Since the early days of photovoltaics in the 1950s, crystalline silicon solar cells have been the workhorse of this strongly growing industry. Since then great progress has been achieved in decreasing production costs from hundreds of US dollars per Wp down to values well below $1/Wp. Also the technology itself has been strongly improved, as reflected by increasing cell efficiencies in research and production. The notorious 20% hurdle, exceeded only by a small number of companies a few years ago, is now cleared by more and more companies. This chapter gives an overview of the exciting technological developments in research and production. A loss analysis is used to categorize the different cell structures and technologies such as selective emitters, dielectric rear passivation, p-type versus n-type silicon, back-contact structures, heterojunctions and passivated contacts.