A method is provided to produce a low-resistivity ohmic contact having high optical reflectivity on one side of a semiconductor device. The contact is formed by coating the semiconductor substrate with a thin metal film on the back reflecting side and then optically processing the wafer by illuminating...http://www.google.com.au/patents/US5429985?utm_source=gb-gplus-sharePatent US5429985 - Fabrication of optically reflecting ohmic contacts for semiconductor devices
