RF MEMS--A Technology Analysis

Abstract

Reliability and Packaging Issues Challenge RF MEMS Technology

Recent years have seen tremendous advances in microelectromechanical system (MEMS) technology, to the extent that it is now being applied even in radio frequency (RF). These revolutionary RF MEMS devices are attracting great attention but are unlikely to achieve mass market adoption until certain core issues are resolved. Some of the major reliability issues include temperature drift, life, degradation dielectric (breakdown, leakage), and stiction. The packaging in MEMS also presents strong challenges, since freestanding mechanical structures must be protected and stay uncontaminated during both the manufacturing process as well as the lifetime of the component. Moreover, the layout and materials used in the packaging of RF MEMS devices are critical since they greatly affect product performance. For the moment, military, space, and instrumentation applications remain the pioneering enablers of RF MEMS technology.

This Technical Insights research service provides a detailed analysis of emerging RF MEMS technologies and their major potential applications. It discusses important technology developments and trends worldwide in the RF MEMS domain, and provides a breakdown of critical ongoing research by region.

Communications Grow Ever More Sophisticated with RF MEMS

Despite its many challenges, RF MEMS potential to revolutionize communications is immense. Components based on this technology deliver superior RF performance and tunability over a much broader range of operating frequencies. For instance, an RF MEMS switch concurrently provides greatly improved insertion loss, isolation, and linearity. RF MEMS devices can potentially be used as microswitches to build impedance networks in front of power amplifiers and to decrease the number of components in multistandard mobile phones. They can also be used as MEMS inductors and tunable capacitors for integrated voltage-controlled oscillators (VCOs) in global positioning systems (GPSs).

"Interest in MEMS technology for RF and wireless applications is rapidly rising primarily because of its flexibility," notes the analyst of this research service. "This can be exploited to overcome the limitations associated with integrated RF devices, enabling circuits to attain new levels of performance not otherwise achievable."

Ubiquitous Wireless Connectivity May Well Become a Reality

"RF MEMS enables superior passive devices, such as switches, switchable varactors, inductors, transmission lines, and resonators," says the analyst. "This makes it ideal to enable a plethora of wireless appliances operating in the home/ground, mobile, and space spheres such as handsets, base stations, and satellites." RF MEMS characteristic properties of low power consumption and reconfigurability suggest that ubiquitous wireless connectivity is no longer a distant possibility.

With wireless systems constantly in need of lower weight, volume, cost, and increased functionality, efforts are underway to realize a single-chip RF circuit. Integrating MEMS devices directly on the RF chip can allow numerous discrete components to be replaced, offering better performance and reliability as well as lower cost. Over time, this integration can lead to the replacement of all passive RF chips with on-chip devices, enabling considerable benefits such as smaller form factors for cell phones and added functionalities including Internet connectivity.