How Does a Photovoltaic Solar Cell Work?
Construction A photovoltaic solar cell made up of a semiconductor material that has one positive and one negative side. It has an antireflective coating on the top side of the wafer and non-conductive substrate attached to the bottom side. The semiconductor–an element that gains stability by sharing its electrons with atoms–is usually silicon. One side of the silicon usually is doped with aluminum, gallium or indium to create a scarcity of electrons, and the other side is doped with phosphorous, arsenic or antimony to create a surplus of electrons. Doping means another element’s atoms are dispersed within the silicon. Light Energy to Electricity Photons from the light of the sun are absorbed by the photovoltaic cell. For the photovoltaic solar cell to work, the sun’s energy needs to be above the band gap of the absorbing material. The band gap is the energy required to knock an electron from the orbit of an atom’s nucleus. This free electron can then move about the semiconductor, eff
