Stability of chromium diffusion barriers during anodic bonding in silicon resistor devices

In this work, the stability of chromium diffusion barriers during anodic bonding in silicon resistor devices was investigated. In particular, temperature–voltage–time conditions for failure were identified. It was found that temperatures of 400 °C regardless of voltage and times above 11.5 min were enough to promote failure. Failure was identified by SEM in the form of a line of hills across the device surface where the silicon resistor was underneath. In contrast, temperatures of 300 °C did not promote failure for all the voltages considered and anodization times of up to 1580 min. Hence, the device failure was attributed to electrothermal migration with the thermal component being dominant.