A metal micromechanical resonant switch for on-chip power applications

A micromechanical resonant switch, or “resoswitch” (c.f., Fig. 1), constructed in nickel metal rather than previously used polysilicon attains a switch FOM >;50 THz, which is several times higher than so far attained by power FET devices and pin diodes. Here, the use of metal reduces the “on” resistance of the resoswitch to less than 1Ω, allowing it to generate 17.7dB of sustained electrical power gain at 25MHz when embedded in a simple switched-mode power amplifier circuit, marking the first successful demonstration of RF power gain using a micromechanical resonant switching device. The high FOM of this device may soon permit the near 100% efficiency predicted for Class-E switched-mode power amplifiers that has eluded transistor-based versions for decades. This in turn would greatly extend battery lifetimes for portable wireless communications and other applications.