Ultrafast laser etching of layered materials has found wide application in various fields, yet the laser-induced interaction mechanism at heterogeneous interfaces remains incompletely understood. While interfacial stripping has been recognized as a thermomechanical removal mechanism for metal/polymer layered systems, current numerical investigations are predominantly based on one-dimensional (1D) simulation frameworks, which neglect the spatial Gaussian profile of laser fluence and radial mass and energy transport. As a result, the spatial evolution of this mechanism under realistic laser irradiation remains unclear. Here, we extend the simulation from 1D to a fully coupled two-dimensional (2D) model incorporating spatial Gaussian energy deposition, and validate the mechanism via multipass laser ablation experiments. The results reveal that radial energy and mass transfer accelerate the relaxation of intense temperature and pressure gradients, converting fluence-partitioned localized removal into uniform stripping of the remaining film. Multipass scanning depth experiments confirm that the material removal efficiency at the interface is significantly higher than that in the initial pure metal ablation stage, verifying the transition of the removal mechanism. Furthermore, the critical thickness threshold for copper stripping under the applied laser parameters is measured to be 44 ± 1.1 μm, which is challenging to determine via simulation. These findings highlight the role of interfacial stripping in improving material removal efficiency during ultrafast laser processing of metal/polymer layered systems.
- Open Access
- Article
Two-Dimensional Evolution of Thermomechanical Interfacial Stripping in Ultrafast Laser Processing of Metal/Polymer Layered Systems
- Zhidong Huang 1,2,3,
- Yukui Cai 1,2,3,4,*,
- Teng Zhang 5,
- Yunlong Han 5,
- Yunqing Tang 1,2,3,4,
- Xing Li 1,2,3,4,
- Xiaoliang Liang 1,2,3,4 and
- Zhanqiang Liu 1,2,3,4
Author Information
Received: 16 August 2026 | Revised: 08 October 2026 | Accepted: 30 October 2026 | Published: 06 November 2026
Abstract
Graphical Abstract
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