Radio frequency micro-electro-mechanical system (RF MEMS) switches are surface micro-machined devices which use a mechanical movement to switch on or off in the RF transmission line, designed to operate at RF frequencies up to millimetre wave frequencies (0.1 to 40 GHz).

RF MEMS switches are built using advanced surface micro-machining fabrication techniques, resulting in tiny microscopic mechanical switch structures, which offer the ultimate in RF performance. The key advantages over conventional switches include low power consumption, high isolation, low insertion loss, high linearity, reliability and low cost.

There are various types of RF MEMS components, such as CMOS integrable RF MEMS resonators and self- sustained oscillators with small form factor and low phase noise, RF MEMS tunable inductors, and RF MEMS switches, switched capacitors and varactors. RF MEMS switches operate in a similar way to conventional RF mechanical relays, but on a silicon chip size scale.

Based on semiconductor fabrication process, RF MEMS technology also presents high integration as above-IC and above-IPD (Integrated Passive Devices) manufacturing capabilities.