This paper presents an extension to a general-purpose hydrodynamic simulation model for laser-based processes, enabling the simulation of ultrashort pulse laser ablation of dielectric materials. The model incorporates free electron generation through multi-photon and tunneling ionization, avalanche ionization, charge carrier recombination, as well as their diffusion and advection. These processes are fully coupled with compressible multi-phase hydrodynamic equations, allowing for the investigation of phenomena typically unobservable experimentally.\\

A comprehensive validation against experimental data assesses the model's accuracy across various laser parameters. The study also includes a detailed parameter analysis, providing insights into optimal processing conditions. Additionally, the effects of novel beam shapes on ablation dynamics and material removal efficiency are explored, such as the employment of Laguerre-Gaussian beams with orbital angular momentum, so called vortex beams. This extended model offers a powerful tool for understanding and optimizing ultrashort pulse laser ablation of dielectric materials.

Ultra-short pulsed (USP) laser ablation of metals is a key process in precision manufacturing, enabling applications such as micro-drilling. Advancing both its fundamental understanding and industrial applicability requires a detailed investigation of the underlying ablation mechanisms.

This work presents results of a fully three-dimensional multiphysical simulation framework based on continuum mechanics, incorporating a two-temperature model, Drude absorption, compressible Navier-Stokes equations, and pressure- and temperature-based phase change models. To enhance predictive power, a pseudo van der Waals equation of state for the gas phase and a novel material model for the liquid phase have been implemented, specifically designed to address near-critical and supercritical regimes.

The study elucidates ablation mechanisms, from spallation to phase explosion, across a wide range of fluences governed by variations in pulse energy, diameter, and duration. The findings provide new insights into USP laser-metal interactions, contributing to both improved process understanding and optimized laser processing strategies.

The package Macromax treats the solution of Maxwell's equations as a scattering network and enables high acceleration of wave calculations through GPU acceleration. It has been extended to allow the simulation of 2D laser ablation with high resolution in the nanometer range for rectangular grids with sizes from thousands to tens of thousands of square micrometers.

This approach allows the laser drilling process to be studied in detail, including the absorption mechanisms of capillaries, incubation and the side-channel phenomenon. The numerical results are analyzed and compared with experimental findings.

In semiconductor manufacturing, achieving smooth, defect-free surfaces on silicon wafers is critical for advanced electronic and photonic devices. Laser polishing offers a promising solution, yet controlling heat transfer to prevent microcracks, excessive heat-affected zones (HAZ), and surface defects remains a major challenge. In this research, numerical simulations are used to investigate the influence of laser parameters including laser power, frequency, and scanning speed on temperature distribution, melt pool depth, and final surface integrity. The results highlight the necessity of carefully optimizing these parameters to control thermal gradient, minimize HAZ formation, reduce roughness, and preserve wafer integrity. By systematically tuning process parameters within narrow operational ranges, the simulation framework provides a robust predictive tool for defect-free laser polishing on silicon substrates. This work paves the way for more efficient, high-precision polishing processes in the semiconductor industry, ultimately contributing to the reliable and cost-effective production of next-generation devices.

Beam shaping is essential for optimizing femtosecond laser micro-processing, especially as higher laser powers, including kilowatt-class systems, become available. However, identifying the ideal beam shape for each application remains challenging.

In this work, we present a numerical simulation model designed to efficiently predict the impact of various beam shapes on femtosecond laser processing. The approach is based on the Two-Temperature Model (TTM), allowing for rapid simulations of energy absorption and heat dissipation dynamics. We will detail the computational methods used, the model validation process, and its predictive capabilities.

The study explores the effect of specific beam shapes on different materials, demonstrating how optimized profiles can enhance precision in machining, reduce tapering, and improve ablation efficiency. Simulated performance metrics will be compared against conventional Gaussian beam processing to highlight the advantages of advanced beam shaping strategies.

An essential basis for reliable and targeted process control is understanding the interaction between the laser beam and the material being processed. The use of low-coherence interferometry (OCT) as a sensor technology for laser microprocesses is an example of the possible applications for obtaining in-situ processing results.

Since most applications with short or ultrashort pulsed lasers are a combination with scanning technology to deflect the laser beam, the sensor must be adapted to these specific processing heads. This contribution deals with applications where it is necessary to measure the ablation depth in-situ in order to control the process. With a high measurement frequency of the sensor device, it is possible to achieve this goal if the wavelength of the light source is carefully chosen to reduce the chromatic shift induced by the F-theta lens in the scanner device.