A holistic X-ray analytical approach to support sensor design and fabrication: Strain and cracking analysis for wafer bonding processes

Devices such as sensors, actuators, or micro-electromechanical systems (MEMS) are obtained by a variety of microfabrication processes. Many these processes influence the material introduction strain and defects, which may affect final device's performance reliability. Indeed, controlling materials' status during is fundamental for process optimization itself guaranteeing highest devices performances their lifetime. In this work, conjoint analytical approach between high-resolution X-ray diffraction (HRXRD) micro-computed tomography (CT) evaluates an innovative silicon-to-sapphire wafer bonding process. Large cracks 30–60 µm-thick were identified in both crystals micro-CT related to interfacial high-stress release. parallel, multi-domain microstructure associated with tilt silicon crystallinity due smaller defects originate at interface travel outer part crystal. The effectiveness also assessed our further enforced means SEM observation sample cross-section. Here, unique combining micro CT HRXRD holistic evaluation wafer-bonding correlate micrometer scale volumetric defect detection (voids cracks) atomic-level analysis presented.