Modeling and simulation of laser material interaction for bulk sapphire

Background

Sapphire, also known as single crystal aluminum oxide, alpha-alumina or simply alumina is a single crystal form of the mineral corundum. Its unique properties makes it a first choice for many high performance applications. When exposed to femto- or pico-second pulsed laser radiation, this chemically inert crystalline material is amorphousized and the irradiated material can subsequently be selectively etched. This technique allows the fabrication of structures in/below the surface of sapphire substrates, for example micro/nano-sized features (on sapphire surfaces), or embedded microfluidic networks (inside the bulk of sapphire substrates).

Objective

The more efficient and cost-effective method to predict the outcome of the laser-material interaction during the formation of subsurface modifications in crystalline sapphire is to simulate this behavior through a numerical model. Objective of this MSc. thesis is to develop a model for laser material interaction inside the bulk of a sapphire substrate. Primary goal of the model is the selection of suitable laser processing conditions for the modification of sapphire. For the purpose of validating the model, a secondary goal is to obtain a reasonable match between results of the modelling with the experimental outcomes.

Preliminary Tasks

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Detailed literature study on laser-material interaction and sapphire micro processing

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Study of modelling methods for laser-material interaction

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Introduction to the µLab (WH-117) and experimental set-up

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Analysis of modelling outcomes and critical comparison with experimental results

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Writing MSc. thesis, and preparation of thesis defence

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Periodical progress meetings with supervisors

Duration

Equivalent to 40 EC

Supervisors

Dr.ir. G.R.B.E. Römer (g.r.b.e.romer@utwente.nl)

MSc. Luigi Capuano (l.capuano@utwente.nl)