Porous Silicon Oxide Anti-Reflection Coating for Solar Cells

A very useful anti-reflection (AR) coating, having characteristics quite similar to silicon monoxide, has been grown on P+N solar cells by a simple technique. ESCA, infrared absorption, and ellipsornetry analysis of the films indicated that they consist of silicon oxide with some bound hydrogen. Some added advantages of the new AR coating are described. The minimization of the optical losses in solar cells is one of the major steps in the improvement of solar cell efficiency. Bare silicon has been shown to be capa-ble of absorbing only 62.5 % (1) of the useful incident solar radiation (photons with hv> Eg). These reflec-tion losses are generally minimized by the use of a suitable anti-reflection (AR) coating. To date, the materials which have been widely used for AR coatings are SiO, TiOx, Ta205, ZnS, and CeO2. A comparative study of the performar, ce of these AR coatings (2) ha