MANUFACTURING LIGA-MASKS WITH LASER MICROMACHINING
- Mr. Aleksandr GENTSELEV
- Mr. Aleksandr GENTSELEV (Budker INP, Novosibirsk, Russia)
- Mr. Sergei KUZNETSOV (Novosibirsk State University)
- Dr. Victor BESSMELTSEV (Federal State Scientific Institution Institute of Automation and Electrometry Siberian Branch of the Russian Academy of Sciences)
- Mr. Sergei BAEV (Federal State Scientific Institution Institute of Automation and Electrometry Siberian Branch of the Russian Academy of Sciences)
- Mr. Evgenii LONSHAKOV (Federal State Scientific Institution Institute of Automation and Electrometry Siberian Branch of the Russian Academy of Sciences)
In the LIGA-technology, the first stage in forming a micro-relief is the deep X-ray lithography which is implemented, as a rule, by using synchrotron radiation (SR) of the wavelength spectral range λ ≈ 1÷3 Ǻ. Realization of this technology implies availability of a high-contrast X-ray mask (LIGA-mask) containing X-ray opaque topological drawing which is normally formed via galvanic deposition of heavy metals on the surface of a X-ray transparent bearing membrane. It is worth noting that a number of products made with the LIGA-technology, e.g. quasi-optical terahertz filters and focusing elements are characterized by self-bearing topology. It opens up a possibility of the structure’s production by means of the alternative but significantly simpler technology – laser cutting of a metal foil that allows eliminating the bearing membrane and excludes technological problems related with electroplating. In this work, we describe the results of experiments with two different laser systems based on solid-state pulsed lasers (λ1 ≈ 1064 nm, λ2 ≈ 532 nm, pulse duration ~ 10 ns) which were utilized for producing LIGA-masks via patterning brass and lead foils 50 um thick. The best results from the viewpoint of the cut edge roughness were obtained with a brass foil patterned with the 1064-nm-laser which provided the average roughness size ~ ±2÷3 um. The technological constraints imposed by the proposed laser technique on the structural geometrical parameters of LIGA-masks, as well as the ways for their mitigation are discussed.