Micromachining of Poly (Methyl Methacrylate) Polymer Using Krf Excimer Laser

In the present work micromachining of PMMA was carried out using KrF excimer laser. Excimer laser pulse with a wavelength of 248 nm was generated with a coherent COMPexPro 110 excimer laser system. A micro-hole of Ø150 μm was machined on PMMA substrate during the experimentation. The PMMA substrate was mounted on the translation stage. The PMMA substrates were ex-posed to different number of pulses (1, 2, 5, 10, 20, 50 and 100) at repetition rate of 2, 5 and 10 Hz respectively by keeping the pulse energy unchanged at 200 mJ. In the present experimentation, the effect of pulse repetition rate and number of pulses on ablation depth has been investigated. The experimental results for micromachining demonstrate ablation process as a photo-chemical mechanism. The results of the experimentation have revealed that, ablation depth is directly proportional to pulse number & pulse repetition rate has no significant effects on the ablation depth.