Temperature stability of a piezoresistive MEMS resonator including self-heating

Temperature stability of a piezoresistive 1.5 μm thin SOI resonator at 74 MHz is presented. As compared to capacitive resonators the self-heating due to the bias current causes a further decrease of the resonator frequency, in addition to the well-known dependency on ambient temperature. The interpretation of the resonance frequency as a device temperature is not obvious anymore under self-heating due to the inhomogeneous temperature distribution.