Surface and structural investigations on laser irradiated P-type silicon

Abstract

P-type silicon (100) is irradiated with Nd:YAG laser (532 nm, 500 mJ and 6–7 ns) in air at room temperature for two different laser incident angles 0° and 45° with the surface normal of the target for 10–50 laser shots with a step of 10 shots. The surface morphological changes of exposed samples are explored by making use of the scanning electron microscope. The variations in crystal structure and crystallinity along with laser annealing effects are examined by employing Raman spectroscopy. The thermal sputtering, hydrodynamic sputtering, exfoliation sputtering, whisker formation and bubble bursting are the salient features found on the irradiated surfaces. An increase in laser shots causes incremental changes in area of melted and heat-affected zones and Raman shifts.