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Assessing failure in epitaxially encapsulated micro-scale sensors using micro and nano x-ray computed tomography

  • Lizmarie Comenencia Ortiz (a1), David B. Heinz (a1), Ian B. Flader (a1), Anne L. Alter (a1), Dongsuk D. Shin (a1), Yunhan Chen (a1) and Thomas W. Kenny (a1)...


Millions of micro electro mechanical system sensors are fabricated each year using an ultra-clean process that allows for a vacuum-encapsulated cavity. These devices have a multi-layer structure that contains hidden layers with highly doped silicon, which makes common imaging techniques ineffective. Thus, examining device features post-fabrication, and testing, is a significant challenge. Here, we use a combination of micro- and nano-scale x-ray computed tomography to study device features and assess failure mechanisms in such devices without destroying the ultra-clean cavity. This provides a unique opportunity to examine surfaces and trace failure mechanisms to specific steps in the fabrication process.


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Address all correspondence to Lizmarie Comenencia Ortiz at


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Assessing failure in epitaxially encapsulated micro-scale sensors using micro and nano x-ray computed tomography

  • Lizmarie Comenencia Ortiz (a1), David B. Heinz (a1), Ian B. Flader (a1), Anne L. Alter (a1), Dongsuk D. Shin (a1), Yunhan Chen (a1) and Thomas W. Kenny (a1)...


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