Pulsed TEA CO2 laser surface modifications of silicon

作者：Trtica MS^*; Gakovic BA

来源：Applied Surface Science, 2003, 205(1-4): 336-342.

DOI：10.1016/S0169-4332(02)01156-X

• laser surface modification
• silicon
• laser-induced periodic microstructure
• pulsed TEA carbon dioxide laser

The interaction of a transversely excited atmospheric (TEA) CO, laser, pulse duration of about 2 mus (FWHM of initial spike = 120 ns), with p-type single crystalline silicon doped by boron, was studied. The results have shown that the silicon was surface modified by the laser beam of 12.0 J cm(-2) energy density. The energy absorbed from the CO, laser beam is converted partially into thermal energy, which generates a series of effects such as melting, vaporisation of molten material, shock waves, etc. Morphological manifestations on the silicon surface are: nonuniform modifications (central zone of interaction); wave-like periodical microstructure (inner periphery zone); hydrodynamical structure-like droplets (outer periphery zone). Wave-like microstructure consists of periodic parallel fringes with a period of about 0.8 mum. Formation of these wave-like microstructures is very complex. Explanation includes a consideration of the laser-induced periodic surface structure (LIPSS) effect. The process of the CO2 laser interaction with silicon was not initially accompanied by plasma. Plasma, in the form of a spark, typically appeared after about 100 cumulated laser pulses.

• 出版日期2003-1-31