Femtosecond Laser Micro/nano Machining on Metallic and Semiconductor Materials

Abstract

Formation of ripples or laser induced periodic surface structures (LIPSS) on semiconductor material like Silicon (Si) and on metals like Aluminum (Al) and Copper (Cu) and fabrication Silver (Ag) nanostructures in polymer matrix by femtosecond (fs) laser direct writing are reported in this paper. Laser irradiation was performed at normal incidence in air using linearly polarized Ti:Sapphire fs laser pulses of ~ 110 fs pulse duration and ~ 800 nm wavelength. Field emission scanning electron microscopy (FESEM) is utilized for imaging surface morphologies of laser written structures, revealing that surface morphology depends on various material processing parameters like laser fluence, polarization, material properties and number of applied pulses. Formation of polymer capped Ag nanoparticles inside the laser written microstructures is confirmed by the appearance of surface plasmon absorption band at 448 nm in the UV-Vis extinction spectrum. Nanoparticles formed were spherical in shape with an average particle size less than 20 nm. This technique is efficient, universal, cost-effective, and environmental friendly, which has potential applications in the fabrication of micro/nanostructures on variety of materials for microelectromechanical systems, nanoelectronics and nanophotonics.