Silicon has a nearly optimum bandgap for sunlight absorptionand silicon solar cells reach a high photoconversion eciencydue to the good material quality and widespread technologicalknow-how. Moreover, Si solar cells have several strong advantagesessential for photovoltaics, such as abundant raw material supply,low toxicity, low cost and scalable technologies for cell and modulefabrication. These advantages are at the origin of the sharp increasein the number of photovoltaic installations in the world, and mostprobably the same trend will continue in the future. Improving theeciency of Si solar cells is key to further reduce area-related costsand to ascertain the position of photovoltaics as a renewable sourceof electricity