Ingolf LeidertProduct Manager Device Testing Spektra Dresden
Sensortest under high-frequency stimulus
Modern MEMS sensors demand an increased testing coverage compared to previous generations. Applications like AR, high precision condition monitoring and ADAS are pushing sensor designers and the sensor manufacturing chain to deliver higher accuracy and much higher robustness than ever. While the basic robustness and reliability features can be partly covered by optimized MEMS design and manufacturing process technology improvements, the majority of full characterization tests can only be performed when all sensor components have been wafer tested, stacked, properly connected and finally assembled in a package – almost ready to ship. Only at the end of the production line a complete sensor system exists that can be tested under sensor stimulation conditions.
But during final test of packaged MEMS sensors only essential tests can be performed – a trade-off between necessary test coverage, test duration and test costs have to be maintained. A cost-optimized System Level testing solution (SLT) can achieve this. So the full test coverage as presumably required by the named applications, has to be done during sensor development and characterization phases and during constant quality assurance tests. For inertial sensors these tests usually include various motion tests like vibration, shock or rotation testing. In this presentation a high-frequency stimulation system for MEMS sensor characterization will be presented that allow the testing in frequency ranges beyond existing limits. A possible combination of this high-frequency stimulation system and a compact SLT solution will be shown as well.