Mohammad Mayyas – MS Thesis Abstract

Supervising Professor: Panayiotis S. Shiakolas 

Title: Wafer surface reconstruction and characterization for motion compensation
in a femtosecond laser micromachining system 

Wafer surface micromachining in a Femtosecond-laser system requires evaluation of target DEM’s of the real wafer-surface into motion coordinates system x , y & z . Surface topography has thus been constructed from scattered control points by TPS algorithm which smoothen surface roughness. The DEM’s of target points which trace mask substrate geometry was extracted from the constructed surface. And the motion stages in system were compensated such that the focused laser spot elevation positions be referenced to the motion-coordinates. 

Further investigations in wafer-surface quality were characterized into visual effects and parameters that help in assessing proper wafer choice. In this study, experiments were suggested to validate the orthogonality of laser beam on any point on wafer-surface. Preliminary experimental setups were suggested to geometrically calibrate laser, lenses and stages. Algorithms were developed for the construction of topographical surfaces, compensation, visualization effects and simulation of final the micromachined-surface.