Whiskerlike structure growth on silicon exposed to ArF: Excimer laser irradiation

The effects of ArF excimer laser irradiation on silicon single crystals in air have been studied. The etch rate versus fluence curve shows three well defined zones, with very different etch rates and dependences. In the intermediate zone (from 1.5 to 2.5 J/cm(2)), narrow (1-2 mu m diameter) and tall columns (3-30 mu m) start to grow after irradiation with some hundreds of laser pulses. These whiskerlike columns, with height between one and two orders of magnitude higher than the depth of the crater, have not been formed by preferential etching of the surrounding material, but through hydrodynamical processes. (C) 1996 American Institute of Physics.