Pulsed laser induced damage in SOI material Original Research Article

Laser-induced damage in silicon-on-insulator (SOI) material is investigated with 1064 nm laser pulses. As the laser pulse duration is increased from 190 ps to 1.14 s, the damage threshold of SOI material decreases from 1.3×1010 to 7.7×103 W/cm2 in laser flux. It is found that the damage threshold varies inversely as the pulse duration for a short irradiation time, and is independent of pulse duration for a long irradiation time. The time dependence is in good agreement with a thermal model which well describes the thermal-induced damage in a semi-finite material irradiated by a Gaussian laser beam. The values of absorption coefficient and thermal conductivity under laser irradiation are calculated as 1.1×103 cm−1 and 0.18 Wcm−1 K−1, respectively, by fitting the model to the experimental results. These results on material damage can be used to predict the damage thresholds of SOI-based devices.