Multi-pulse agglomeration effects on ultrashort pulsed direct laser interference patterning of Cu

• Published in: Applied surface science Vol. 611; p. 155538
• Main Authors: Müller, Daniel Wyn, Lößlein, Sarah, Pauly, Christoph, Briesenick, Max, Kickelbick, Guido, Mücklich, Frank
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.02.2023
• Subjects: Biomimetic surface structures; Direct laser interference patterning; Functional surfaces; Ultrashort laser pulses; Direct laser interference patterning; Functional surfaces; Biomimetic surface structures; Ultrashort laser pulses
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2022.155538

Surface functionalization by biomimetic patterns in the micro- and nanometer scale is well-established in a wide range of applications. The finely tuned surface properties are directly related to both primary and sub-pattern morphology of the applied topographies, which must be well-adjusted for maximum functionalization efficiency. In this light, the role of proceeding surface modification and its effect on pattern formation alongside multi-pulse ultrashort pulsed direct laser interference patterning (USP-DLIP) of Cu are investigated in detail by applying a multi-method characterization approach. It was shown that aside of topographical remodeling, USP-DLIP processing parallelly affects chemistry and the mechanical deformation state of the substrate surface, which in turn considerably influences laser/material interaction via incubation. An in-depth investigation of the individual and combined impacts of these substrate alterations on localized optical absorptance reveals how primary and sub-pattern formation dynamically respond to process induced surface modification. The DLIP-specific incubation impact on pattern morphology increases with inverted relation to pattern scale. The findings of this study provide a profound insight in the predominant physical interactions involved in pattern formation arising from the mutual influence between laser irradiation and substrate modification during USP-DLIP-processing of Cu allowing for high precision micro- and nanometer scaled pattern design. [Display omitted] •Substrate modification during USP-DLIP process affects laser/material interaction.•The incubation like behavior involves multiple impacts on localized absorptance.•Modified surface chemistry and pattern topography formation prominently impact DLIP.•Ablation is shaped by superposition of interference pattern and localized absorptance.•Pattern morphology depends on interplay of ablation kinetics and pattern scale.