Abstract

Femtosecond laser direct writing (FsLDW) has recently been considered as a promising tool for fabrication of functional devices that are otherwise not possible. Examples range from micro-optics, micro-electronics, micromechanics, microfluidics, to optoelectronic, sensing, biomimetic and biological devices and systems [1-6]. The unique fabrication capability have been made possible due to the nonlinear femtosecond laser light-matter interaction features: (i) the relatively deep penetration of light into materials due to usage of near-infrared wavelength avoiding linear absorption, and (ii) the simultaneous absorption of multiphotons at a tiny focal spot far smaller than the diffraction volume because of the extremely large photon flux density. The high nonlinearity and therefore the high fabrication spatial resolution was enabled spatially by high numerical aperture lenses focusing, and temporarily by adopting fs pulsed laser.

© 2015 IEEE