Dual-clock with single and monolithical 0-level vacuum packaged MEMS-on-CMOS resonator

Abstract

This paper demonstrates the feasibility of a novel fabrication approach of MEMS resonators above standard CMOS circuitry and with zero-level vacuum package. As a proof of concept a monolithical CMOS-MEMS-closed loop oscillator showing dual-clock capabilities (11.9 MHz and 24.5 MHz) is presented. These two frequencies correspond to two different resonator modes, specifically the torsional and vertical out of plane, of a paddle shaped MEMS resonator.