Optical processing: a novel technology for fabricating solar cell contacts

A novel semiconductor device processing technology is described that uses optical energy of a preselected spectrum to produce local melting at an illuminated semiconductor-metal (S-M) interface. This local melting results in an alloyed ohmic contact of very low contact resistivity. This process (called optical processing) takes place in a “cold wall” furnace, and is very insensitive to impurity contamination. The authors describe the application of optical processing to the formation of low-resistivity contacts on the front and back sides of a silicon solar cell in a one-step process. This process can result in considerable cost savings compared to conventional approaches for fabricating contacts on solar cells