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Ion beam milling is a technique in which the convex parts of a film is flattened and scraped off by an ion beam.
It is mainly used in the processing of high frequency filters, such as the BAW filter and the SAW filter.
High-frequency filters have become crucial for 5G communications. A single 5G-capable device is equipped with approximately 20 -40 filters.
In the manufacturing of high-frequency filters, uniformity of the Nitride and Oxide films on the filter is crucial. Even if the film looks to be uniformly deposited by CVD, etc., it is still uneven at the atomic level. The role of ion beam milling is to flatten this uneveness.
Thin beam applied to the convex parts to scrape them off, achieving flatness equivalent to only 1 mm of uneveness in a 150 km circle (equivalent to the whole Kanto region of Japan).
ULVAC Equipment for Sc (AlN) membrane ion milling for BAW devices