Piezoelectric MEMS silicon resonator and electronic device

Abstract

The invention discloses a piezoelectric MEMS (Micro Electro Mechanical System) silicon resonator and electronic equipment. The piezoelectric MEMS silicon resonator comprises a cantilever beam arranged along a first direction, the cantilever beam comprises an electrode layer, a piezoelectric layer and a silicon temperature compensation layer which are stacked along a second direction, the first direction is perpendicular to the second direction, and the silicon temperature compensation layer is made of a non-uniformly doped silicon material. According to parameters such as temperature distribution, stress distribution and displacement distribution of the resonator in a resonance state, a non-uniform distribution doping scheme is adopted in a silicon structure in the resonator, corresponding doping concentrations are designed according to requirements of different parts, and more accurate temperature compensation is realized. Besides, the distribution of the rigidity of the monocrystalline silicon is adjusted through the concentration distribution, and when the rigidity distribution is matched with the stress, strain or displacement field distribution to a certain extent, the electromechanical coupling coefficient of the resonator is improved.

Description

technical field [0001] The invention relates to the technical field of resonators, in particular to a piezoelectric MEMS silicon resonator and electronic equipment. Background technique [0002] Due to thermal expansion and contraction of materials, the resonant frequency of the resonator will drift with temperature. The sensitivity of the resonant frequency of the device to temperature changes can be expressed by the temperature coefficient of frequency (TCF, temperature coefficient of frequency), which means the change in resonant frequency per degree of temperature change. For a composite structure composed of multiple layers of different materials, the equivalent frequency temperature coefficient is the weighted average of the frequency temperature coefficient of each layer of material, which can be expressed as: [0003] [0004] Among them, λ n is the composite equivalent frequency temperature coefficient, is the n-order frequency temperature coefficient of the ...

AI Technical Summary

Problems solved by technology

However, this method is difficult to take into account the high-order frequency temperature coefficient, and the quality factor and electromechanical coupling coefficient of the resonator may therefore deteriorate

Images