RF MEMS: Focusing on the next step

Radio frequency and mixed signal semiconductor technologies have been improving and play a big role in the rapidly growing market of wireless communication. Higher integration of CMOS technologies due to “More Moore”s Law is helping this success. In parallel, some of the RF micro device technologies have been very popular, especially for frequency selection such as piezoelectric material devices by using MEMS technology. On the other hand, there are many wireless services already in existence such as various kind of cellular standards, many private systems representing IEEE 802.11/15 WLAN, Bluetooth, and public mobile services, and also there are coming up new systems such as “Ultra Wide Band”, and “Wireless Sensor Network”. Since all these services have different carrier frequencies, channel bandwidth, and various kinds of modulation systems a single solution is not tenable. This led the industry toward the concept of the “Software Defined Radio”. This has been discussed for many years, leading to a vision of a “Cognitive Radio”. Expectation of a “Cognitive Radio” is that it can change its radio functions by swapping software instead of replacing hardware. It is clear that conventional A/D converters with high data rates and large dynamic range will not suffice. Thus, it has been said that RF MEMS is a strong contender as a complimentary technology, allowing “More Than Moore” to enable the ubiquitous connectivity. Paper discussed current status of the RF MEMS technology briefly including switches, LC, oscillators/filters using Piezoelectric materials, Silicon, and Metal, besides focusing on the next step of RF MEMS with the keyword of “Tunable”, “Selectable” and “Combination”. The focus for RF MEMS for the next step demonstrated, “Matching modules”, “Front Ends”, “Filter Banks”, “Improving the resonator performances for the wireless application” and “Creating new functions for RF MEMS”. The next step for RF MEMS is not only technology discussions, but also the international standardization for the RF MEMS industry and wireless communication products.