Thermal Evaporation is one of the simplest forms of physical vapor deposition (PVD). It uses heat to evaporate a high purity source material that moves through a vacuum chamber and deposits a thin film on a substrate. Thermal evaporation can be used to deposit metals, organic, and inorganic polymers. In this method, electrical energy is used to heat a filament which in turn heats a deposition material to the point of evaporation. The process can be performed at very high levels of vacuum to eliminate collisions with foreign particles and therefore fewer tendencies to introduce film impurities. High deposition rates can be achieved and lower energy particles can reduce substrate damage.Thermal evaporation is widely used when creating polymer solar cells and flexible electronics.