MEMS-based dual and single proof-mass accelerometer methods and apparatus
AssigneemCube Inc.
InventorsDolf van der Heide, Shingo Yoneoka
Life of this patent
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Abstract
An integrated MEMS inertial sensor device includes one or more three-axis MEMS inertial sensor devices, such as accelerometers, with dual or single proof mass configurations. These designs can be compact and can decouple the motion of each axis to minimize the measurement errors due to cross-axis sensitivity. Some embodiments include a frame to decouple the motion of two axes and to provide geometric symmetry. Some embodiments also include double-folded springs. In a specific embodiment, the three axes of an integrated MEMS accelerometer device are entirely decoupled. Thus, the actuation of each axis, through a force due to acceleration, has little or substantially no effect on the other axes.
Claims15
An integrated MEMS (Micro-Electro-Mechanical-Systems) inertial sensor device, the device comprising:
- a substrate member having a surface region;
- a first proof mass overlying the surface region;
- a first frame overlying the surface region;
- at least one frame spring physically coupled to the first frame and the first proof mass;
- at least one first anchor physically coupled to the surface region;
- at least one first spring physically coupled to the first frame and the first anchor, the first spring including a doubly-folded spring;
- wherein the first proof mass is physically coupled to the first frame via the first spring, the first frame being physically coupled to the first anchor via the first spring;
- a second proof mass overlying the surface region, the second proof mass having a center cavity, wherein the first proof mass is spatially disposed within the center cavity;
- at least one second anchor physically coupled to the surface region;
- and
- at least one second spring physically coupled to the second proof mass and the second anchor.
An integrated MEMS (Micro-Electro-Mechanical-Systems) inertial sensor device, the device comprising:
- a substrate having a surface region;
- an IC layer overlying the surface region;
- a first proof mass overlying the surface region, the first proof mass having a plurality of electrode cavities;
- a second proof mass overlying the surface region, the second proof mass having a center cavity, wherein the first proof mass is configured within the center cavity;
- a frame overlying the surface region, the frame being configured within the center cavity, wherein the first proof mass is configured within the frame;
- at least two doubly-folded springs physically coupled to the first proof mass and the frame;
- at least two first anchors physically coupled to the surface region, the first anchors being configured within the center cavity;
- at least two doubly-folded springs physically coupled to the first anchors and the frame;
- at least two second anchors physically coupled to the surface region, the second anchors being configured within the center cavity;
- at least two springs physically coupled to the second anchors and the second proof mass;
- and
- a plurality of electrode structures coupled to the surface region, each of the plurality of electrode structures being configured within one of the plurality of electrode cavities, the plurality of electrode structures being electrically coupled to the IC layer.
Dependencies are inferred from the claim text.