Mixing in a 220MHz CMOS-MEMS

This paper describes the frequency mixing operation of a Micro Electro Mechanical System device designed and fabricated in a CMOS commercial technology (AMS 0.35μm). The theory of the MEMS is summarized and a CMOS fully integrated MEMS is characterized as a mixer. The designed MEMS is a polysilicon clamped-clamped beam that presents a resonance frequency in the VHF range. CMOS-MEMS based mixer limitations are treated and a technique based on differential amplification to improve performance is given.