Ultrashort pulse laser micromachined microchannels and their application in an optical switch

Abstract

The capability of direct writing makes ultrashort pulse laser significant in the microfabrication of MEMS devices based on polymer and glass. In particular, nanosecond and femtosecond lasers are able to transfer the adequate energy in femtosecond intervals for the removal of the materials. Because of its advantages, just like the small feature size, smooth finishing surface, flexible structuring and the minimum thermal effect, ultrashort pulse lasers have become a convincing technique with the high peak power. This paper presents the femtosecond laser machining results of the polycarbonate, aluminosilicate glasses and nanosecond laser machining of aluminosilicate glasses. The microchannels with the critical micron-scale dimensions and the sub-micron scale surface roughness were achieved by the optimized operating parameters of the laser. The major influence factors such as cutting speed, power energy, and power stability were analyzed to obtain the optimized parameters for the fabrication of the microchannels for a bubble switch. The ultrashort pulse laser micromachining was applied in the prototype of a bubble optical switch. By miniaturization of the structure of the microchannel, the switch speed can be promisingly improved.

Enhanced depth control of ultrafast laser micromachining of microchannels in soda-lime glass

“…7). However, if lower surface roughness is required, improved surface quality of channels by chemical etching, soft annealing or surface coating with polymers can be used [14][15][16].…”

Precise machining of disk shapes from thick metal substrates by femtosecond laser ablation

“…The short duration of femtosecond laser pulses minimizes heat diffusion into the surrounding materials, leading to small residual thermal stress. Also, ablation of material by direct solid-vapor transition occurs only in limited areas with minimal molten material [1,14,15]. These advantages make the femtosecond laser micromachining process suitable for high-precision material ablation with minimal degradation of mechanical properties of the machined surfaces.…”

Measurement of refractive index change of optical fiber core induced by femtosecond laser scanning

“…7 Destructive fabrication is above the material ablation threshold. Nondestructive fabrication, called subablation fabrication, is below the material ablation threshold.…”