Piezoelectric MEMS resonators based on porous silicon technologies
OwnerXiang Zheng Tuinventor
Life of this patent
Estimating the term…
Abstract
A piezoelectric MEMS resonator is provided. The resonator comprises a single crystal silicon microstructure suspended over a buried cavity created in a silicon substrate and a piezoelectric resonance structure located on the microstructure. The resonator is designed and fabricated based on porous silicon related technologies including selective formation and etching of porous silicon in silicon substrate, porous silicon as scarified material for surface micromachining and porous silicon as substrate for single crystal silicon epitaxial growth. All these porous silicon related technologies are compatible with CMOS technologies and can be conducted in a standard CMOS technologies platform.
Claims9
A piezoelectric MEMS resonator based on porous silicon related technologies, the resonator comprising:
- a microstructure including:
- a silicon substrate, a single crystal silicon epitaxial layer, a buried cavity;
- a single crystal silicon plate and two flexible single crystal silicon beams each made of the single crystal silicon epitaxial layer and suspended over the buried cavity, wherein the single crystal silicon plate is anchored to the silicon substrate through the two flexible single crystal silicon beams;
- a piezoelectric resonance element including:
- a bottom electrode, a middle piezoelectric layer, a top drive electrode, a top sense electrode, and a top electrode isolation gap which are all vertically stacked on the single crystal silicon plate;
- and
- several electric connecting elements including:
- two bonding pads connecting to the bottom electrode and two bonding pads connecting to the drive electrode and the sense electrode respectively, wherein the resonator is configured to operate in lateral resonance mode.
Dependencies are inferred from the claim text.