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Description
Controlling laser-matter interaction is a fundamental prerequisite for the maskless patterning of advanced materials, thin films, and functional optoelectronic architectures. Because modern research frequently relies on high-cost specialized lithographic equipment, industrial laser engravers and markers operating across diverse spectral and temporal regimes present a highly accessible and versatile alternative. However, achieving material modification without uncontrolled thermal damage or phase degradation critically depends on rigorous system calibration and understanding the interrelation between laser parameters.
In this work, we present a comparative methodological study of four industrial laser systems covering a broad spectral range from ultraviolet (UV) to far-infrared (FIR). The practical utility of this multi-system infrastructure was demonstrated through tailored processing protocols for various material classes. The 355 nm UV system enables precise surface ablation and patterning with minimal heat-affected zones due to high photon energy and localized absorption. The 1064 nm NIR fiber laser provides deep photothermal interaction and bulk modification, making it ideal for single-pulse patterning and localized thermal annealing of semiconductor alloys, such as GeSn, VOx, or rGO. The 455 nm diode laser offers controlled continuous-wave thermal treatment and selective reduction of graphene oxide thin films, enabling direct maskless patterning of conductive planar circuits and micro-electrode arrays. Considering the CO₂ system at 10.6 μm, it provides highly efficient photothermal processing of dielectric substrates, oxide materials, and polymers owing to strong infrared absorption.
To ensure reproducible processing conditions, empirical laser power and pulse energy calibration protocols were established using a thermopile power/energy sensor. For the diode-pumped solid-state (DPSS) UV laser operating at 355 nm, the average output power and effective peak pulse power were modeled as non-linear functions of pulse repetition rate and Q-switch interval settings. Calibration of the 455 nm diode system revealed a non-linear optical power response in the low-power domain while maintaining linear scaling of nominal power at higher excitation levels. For the 1064 nm NIR fiber laser, the calibration reveals a distinct lasing threshold near 15% nominal power, above which the real output power increases almost linearly. In the case of the gas CO₂ laser at 10.6 μm, the real power dependence on the nominal setting demonstrates a stable, nearly linear behavior across the entire range (0–100%). Furthermore, pulse repetition frequency variation has a minimal impact on the output power for both IR systems.
Our comparative analysis establishes a practical framework for selecting optimal laser sources, pulse characteristics, and energy density windows, demonstrating that properly calibrated commercial laser markers can substitute expensive lithographic setups for functional prototyping in semiconductor physics and optoelectronics.
Acknowledgements. The work was supported by the National Research Foundation of Ukraine, project # 2023.05/0022.