Fully monolithic MEMS based thermal sensor in 22 nm CMOS technology for SoC thermal managemet

A novel fully monolithic MEMS based thermal sensor for high resolution thermal management is demonstrated in a 22 nm CMOS technology. Top metal layers are used as the structural material for the MEMS clamped-clamped beam resonators used as a thermal sensor. Using the top metal layers avoids any disruption to the complex fin FET transistor front end where the MEMS technology is not really compatible and additionally exploits the thermal characteristics of the device [1-2]. By tracking the resonance frequency of the copper resonator, the temperature of the chip can be tracked to a sub degree granularity with frequency resolution of 6.7 kHz/°C at 15 MHz.