![](https://www.samco.co.jp/products/process/uploads/afee278addcccf5ae1268ef5ab943e9f45dbb117.jpg)
The RIE-400iPB, a silicon deep RIE system for research and development, is used to form a 100 μm wide, 500 μm depth through hole structure. The selectivity of silicon to thermal oxide film, which is a mask, is about 100:1.
Photo courtesy of Yamagata research institute of technology
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