Open AccessModelling laser machining of nickel with spatially shaped three pulse sequences using deep learning
Author(s) -
Michael McDonnell,
James Grant-Jacob,
Yunhui Xie,
Matthew Praeger,
Benita MacKay,
R.W. Eason,
B. Mills
Publication year - 2020
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.381421
Subject(s) - machining , microscale chemistry , femtosecond , laser , optics , artificial neural network , materials science , smoothing , diffraction , computer science , surface roughness , artificial intelligence , computer vision , physics , metallurgy , composite material , mathematics education , mathematics
Femtosecond laser machining is a complex process, owing to the high peak intensities involved. Modelling approaches for the prediction of final sample quality based on photon-atom interactions are therefore challenging to extrapolate up to the microscale and beyond. The problem is compounded when multiple exposures are used to produce a final structure, where surface modifications from previous exposures must be taken into consideration. Neural network approaches allow for the automatic creation of a model that accounts for these challenging processes, without any physical knowledge of the processes being programmed by a specialist. We present such a network for the prediction of surface quality for multi-exposure femtosecond machining on a 5µm electroless nickel layer deposited on copper, where each pulse is uniquely spatially shaped using a spatial light modulator. This neural network modelling method accurately predicts the surface profile after three, sequential, overlapping exposures of dissimilar intensity patterns. It successfully reproduces such effects as the sub-diffraction limit machining feasible with multiple exposures, and the smoothing effect on edge-burr from previous exposures expected in multi-exposure laser machining.