Minimizing Cost Of Calibration And Test (COCT) To Drive Cost Reduction Of MEMS
Authors: John Rychcik, Barbara Loferer Company: Multitest Electronic Systems, Inc. Date Published: 11/5/2013
IWLPC (Wafer-Level Packaging)
Abstract: What used to be a technology driven by high-end automotive and medical applications has become a true commodity: MEMS. Any state-of-the-art electronic gadget ? be it a mobile phone, tablet or camera ? makes extensive use of MEMS components. Gyroscopes, Accelerometers, pressure sensors, magnetometers, microphones and other devices have to be manufactured, calibrated and fully tested at the lowest possible cost. Cost of calibration and test (COCT) is now the single most significant cost factor for a majority of MEMS sensors, particularly in consumer applications. At the same time, many safety and health related MEMS applications remain extremely demanding on device reliability. Therefore, precise device calibration and rigorous testing remain critical requirements. This paper specifically addresses the various approaches to reduce COCT for MEMS with a focus on so called "combosensors" that combine more than one MEMS device in a single package. The main COCT drivers such as the stimulus equipment, its high throughput capability, uptime, short test time, the test equipment itself and the level of test parallelism, are identified and analyzed. A specific MEMS test cell enabling high parallel test while maintaining flexibility with regards to package size (<2mm) and stimulus is described in detail. The authors also lay out a future roadmap as to where MEMS calibration and test technology is headed.