Propagation of Nd-laser pulses through crystalline silicon wafers

Propagation of pulses from an Nd:YAG laser (wavelength, 1.064 μm; pulse duration, 270 ns; pulse energy, 225 μJ) through crystalline silicon wafers is studied experimentally. Mathematical modelling of the process is performed: the heat conduction equation is solved numerically, the temperature dependences of the absorption and refraction of a substance, as well as generation of nonequilibrium carriers by radiation are taken into account. The constructed model satisfactorily explains the experimentally observed intensity oscillations of transmitted radiation.