Accelerated life testing for micro-machined chemical sensors

Reliability and quality assurance are a major concern in the semiconductor industry. However, when developing a new mass-production technology, like micro-machined silicon-based devices, these aspects become particularly critical. Indeed, silicon-based thin-film tin-dioxide gas-sensor reliability has not been deeply studied; most of the completed studies address thick-film devices made on alumina substrates. New test-methods and equipment must be engineered to meet the ever-increasing expectations of the marketplace. This paper justifies the need for new accelerated tests for chemical sensors. A new method which allows `stressing the entire device structure´ has been implemented. Test results obtained using this new approach allow us to evaluate the sensor reliability in the range of the requirements of applications using gas sensors