MEMS, or micro electro mechanical systems, are microscopic devices made using semiconductor technology that rely on physical movement to either sense or react to their environment. Radio Frequency (RF) MEMS are MEMS that use the movement of a tiny mechanical actuator to provide signal processing on RF signals. At Tyndall, we have been actively involved in the design, fabrication and testing of RF MEMS devices for over 15 years. Our particular focus has been capacitive devices for switching and tuning functions in K-band applications.
The Tyndall MEMS switch is a low voltage capacitive device fabricated in a CMOS compatible process. The switches exhibit promising RF performance: an insertion loss of -0.2 dB and an isolation of -19.3 dB at 30 GHz and good reliability: billions of cold-switching cycles have been demonstrated.
Reliability has proven to be a major obstacle in the commercialisation of RF MEMS for companies all over the world and has become the focus of our research here at Tyndall.
Tyndall is committed to studying and understanding both the mechanical and the electrical mechanisms of device degradation and to developing test methodologies that can be used in identifying the dominant causes of failure in a particular device. The Tyndall switch has been successfully used as a test vehicle in designing reliability tests for RF MEMS and has allowed us to grow our understanding of the failure modes of RF MEMS generally.
Due to their multi-domain nature and to the diversity in design and operation, RF MEMS are complex devices to analyse and the design of a test or test suite for reliability is very much device dependent. Our expertise in MEMS reliability extends to both the mechanical and electrical degradation modes and this, along with our suite of optical and electrical measurement equipment has facilitated us in successfully testing a plethora of RF MEMS devices from both commercial and academic suppliers.