ABSTRACT
The direct, environmentally benign and economically efficient conversion of sunlight into electricity is an energy policy imperative on a long time scale. Solar electricity only occupies niche positions - if any - in the energy mix, but solar cell technologies could accomplish more. As far as inorganic materials are concerned, light-induced charge carriers can be generated and separated in semiconductors. Silicon is the most widely used starting material for commercial solar cells. It is also the second most frequent element in the earth’s crust, it is non-toxic and stable, and the processing methods are very well known from information technology and tested. Crystalline silicon is used for conventional solar cells. The advantage of solar cells from single-crystal silicon is their high efficiency, which cannot be achieved using polycrystalline material. The advantage of solar cells from single-crystal silicon is their high efficiency, which cannot be achieved using polycrystalline material.
