The present invention provides methods of fabricating a radiation-absorbing semiconductor wafer by irradiating at least one surface location of a silicon substrate, e.g., an n-doped crystalline silicon, by a plurality of temporally short laser pulses, e.g., femtosecond pulses, while exposing that location...http://www.google.com.au/patents/US7354792?utm_source=gb-gplus-sharePatent US7354792 - Manufacture of silicon-based devices having disordered sulfur-doped surface layers
