Real-Time Machine Learning-Based Position Recognition in Laser Nanofabrication with Sub-Half-Wavelength Precision
Year: 2025
Type: article
Abstract: Laser nanofabrication with tightly focused ultrafast laser pulses enable versatile fabrication of arbitrary two-dimensional (2D)/three-dimensional (3D) micro/nanostructures. Accurate positioning of the laser focal spot is crucial, especially for high-resolution integrated devices in 2D materials, requiring precise placement on atomically thin surfaces. However, uneven surfaces and surface tilt poses significant challenges. Existing methods to detect focal positions often involve complex setups with additional optical components or sensors, achieving limited accuracy. This study introduces a machine learning-based method to accurately detect the focal position during laser nanofabrication by analyzing the shape and intensity of the laser focal spot. We compare four machine learning methods: rational quadratic Gaussian process regression, kernel approximation least square, quadratic support vector machine, and trilayered neural network. Our experiments show that TNN method achieves a detection accuracy of 257 nanometers (nm) (half the fabrication laser wavelength), surpassing the required accuracy for tightly focused laser beam (typically larger than one wavelength). This method can map focal positions along the fabrication trajectory to compensate for surface roughness or tilt. Moreover, it can be directly implemented in any laser nanofabrication system with a camera for in situ monitoring, without requiring additional optical components, indicating broad applicability.
Source: Engineering
Authors: Hao Zhang, Jinchuan Zheng, Guiyuan Cao, Han Lin, Baohua Jia
Language: English
Subfield: Computational Mechanics
Field: Engineering
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $1,300
Funder: Australian Research Council
Awards: Laser nanoprinting of active graphene micro-tag for terahertz digital ID, ARC Training Centre in Surface Engineering for Advanced Materials, Monolithic Solar Thermal Photocatalytic Membrane for Hydrogen Production, High yield adaptive laser nanomanufacturing system for photonic devices, Tailoring smart film for energy efficient protected cropping, Adaptive nanofabrication of monolithic multifunctional sensing chips, Intelligent 3D Laser Nanoprinting Facility with In-situ Characterisation, ARC Centre of Excellence in Optical Microcombs for Breakthrough Science, Radiatively cooled high-performance solar cell
OpenAlex ID: W4411340806