We developed a local irradiation system for atmospheric pressure inductively coupled plasma (ICP) using a quartz capillary nozzle (nanopipette) with a sub-micrometer diameter tip aperture for fine processing of material surface. Using this system, a polymethyl methacrylate (PMMA) film coated on a glass substrate was etched at the micrometer scale. Fine etching was achieved by the ICP localized by the nanopipette precisely placed near the surface, using the positioning capability of a homemade scanning probe microscope. The locally etched surface of the PMMA film was confirmed by imaging immediately after the etching process by scanning the nanopipette. For quantitative evaluation, the topographical image of the same location of the surface was then acquired using an atomic force microscope. The etching rate of the ICP was 20 times higher than that of the low-frequency atmospheric pressure plasma jet. The depth of the etched holes increased with increasing applied power and irradiation time and decreasing irradiation distance. In addition, line groove patterning with sub-micrometer width was successfully achieved. The proposed system is expected to be used in various applications such as processing and repairing of microdevices.

我们开发了一种用于大气压电感耦合等离子体 (ICP) 的局部照射系统，使用石英毛细管喷嘴（纳米移液管）和亚微米直径的尖端孔径，用于材料表面的精细加工。使用该系统，涂覆在玻璃基板上的聚甲基丙烯酸甲酯 (PMMA) 膜以微米级蚀刻。使用自制扫描探针显微镜的定位能力，通过精确放置在表面附近的纳米移液管定位的 ICP 实现了精细蚀刻。PMMA 膜的局部蚀刻表面在蚀刻过程后立即通过扫描纳米移液管进行成像确认。为了定量评估，然后使用原子力显微镜获取表面相同位置的地形图像。ICP的蚀刻速率比低频大气压等离子体射流的蚀刻速率高20倍。蚀刻孔的深度随着施加功率和照射时间的增加以及照射距离的减小而增加。此外，还成功实现了亚微米宽度的线槽图案化。所提出的系统有望用于各种应用，例如微器件的加工和修复。