Optimization of Nd:YAG laser for microchannels fabrication in alumina ceramic

Microchannels are fabricated in alumina ceramic using Nd:YAG direct laser writing. Microchannels having width of 200 mu m and different depths are machined by varying three parameters viz. intensity of laser beam, pulse overlap and scan strategy. Channel's depth, top width error and bottom width error are measured using scanning electron microscopy to assess the dimensional accuracy. The process has been optimized in terms dimensional accuracy for different depth categories using Response Surface Method (RSM) and Lipschitz sampling. It has been found that intensity is the parameter to control depth, MRR and dimensional errors. Dimensional errors can be reduced using low intensity levels and moderate overlaps at the expense of material removal rate. The selection of scan strategy also plays an important role particularly at low intensity levels.