Sub-micron and high precision micro-machining using nanosecond lasers

Short pulse lasers have demonstrated their ability to machine a wide variety of materials with micron precision and micron heat affected zones and recast layers. Whilst there are certain intrinsic advantages in the way in which the ultra-short (femtosecond) pulses interact with certain materials, it is not clear that they have any practical advantage over nanosecond pulses. It is possible to produce both high quality and low quality machining results using a wide variety of pulse formats including nanosecond and femtosecond pulses. In many cases high quality results require that the machining conditions and strategy are optimised for that particular application. Whilst comparison of the machining results under similar conditions but different pulse formats is of interest in understanding the mechanism of the material removal, it is the optimised results and practicality of their implementation that are of real interest to industrial users. We propose that for many applications these results with nanosecond pulses are at least equivalent to the results from femtosecond pulses and that the nanosecond laser is more readily implemented in an industrial production environment.