High aspect ratio (HAR) micro-grooves are of great significance for vacuum electronic devices. However, the fabrication of HAR micro-groove on oxygen-free copper remains challenge since the high surface quality is hard to achieve. Aiming to improve the surface quality, a hybrid and successive method, obtained by combining nanosecond laser and micro-milling (NLMM), was presented. The nanosecond laser achieves the maximum workpiece removal rate, while the subsequent micro-milling provides the desired machining quality. Compared to one-way full slot micro-milling (FSMM), the presented manufacturing method (NLMM) could improve the surface quality, namely the top burr formation and the bottom and sidewall surface roughness. Furthermore, the NLMM displayed a lower tool wear rate compared to FSMM. Finally, a desired S-shaped groove with an aspect ratio of 2.5, a width of 0.2 mm, and the cycle number of 30 was successfully fabricated. The study offers a promising aspect for improving the HAR micro-groove fabrication quality.

高深宽比（HAR）的微槽对于真空电子设备具有重要意义。然而，由于难以实现高表面质量，因此在无氧铜上制造HAR微沟槽仍然具有挑战性。为了提高表面质量，提出了一种结合了纳秒激光和微铣削（NLMM）的混合连续方法。纳秒激光可实现最大的工件去除率，而随后的微铣削则可提供所需的加工质量。与单向全槽微铣削（FSMM）相比，提出的制造方法（NLMM）可以改善表面质量，即顶部毛刺的形成以及底部和侧壁的表面粗糙度。此外，与FSMM相比，NLMM的刀具磨损率更低。最后，成功地制造出纵横比为2.5，宽度为0.2 mm，循环数为30的所需S形凹槽。该研究为改善HAR微槽的制造质量提供了有希望的方面。