CMOS BEOL-embedded lateral accelerometer

In this paper we present to the best of our knowledge a first ever reported CMOS BEOL-embedded lateral acceleration sensor obtained by simple isotropic inter-metal dielectric etching without any additional substrate etching steps. The device leverages the availability of thick metal and via layers of a 0.25 μm RF CMOS technology, featuring 7.36 kHz resonance frequency and differential capacitive sensitivity 0.2 fF/G. The accelerometer is monolithically integrated with on-chip sensing electronics exhibiting 200 μG/√Hz total noise floor at 2.5 V power supply and 550 μA current consumption.