[23p-C205-1~11] 4.3 Lasers and laser materials processing

▼ [23p-C205-2] Parametric dependence of laser induced damage threshold in silicon

〇(P)Prachi Venkat¹, Tomohito Otobe^1,2 (1.KPSI (QST), 2.UT-PSC)

Keywords:Laser processing, Damage threshold

We study the effect of parameters such as laser wavelength and silicon film thickness on the damage threshold during laser excitation of silicon. We use the Three-Temperature model (3TM) to study the effect of varying parameters on laser processing of silicon. The model considers three distinct temperature systems for electrons, holes and the lattice. The evolution of laser field is formulated using FDTD method. The effect of band-renormalization on the optical properties of silicon is also considered. The change in laser wavelength is observed to be crucial as it changes the penetration depth for single- and two-photon absorption, thereby affecting the lattice dynamics and damage threshold. The variation in thickness of silicon film also causes changes in the damage threshold, due to significant reflection from the rear surface of the film. The study of these parameters using 3TM can help understand the effect on damage processes and can be used to optimize these interactions.