Microelectromechanical system
AssigneeMurata Manufacturing Co., Ltd.
InventorsAntti IIHOLA, Matti LIUKKU
Life of this patent
Estimating the term…
Abstract
A microelectromechanical system is provided that includes an ASIC layer, an interposer layer, a MEMS layer with movable structures and a cap layer stacked with each other in a listed order. The interposer layer and the cap layer form one isolated enclosure, and the ASIC layer and the cap layer form another isolated enclosure. Pressures in the isolated enclosures are different. An advantage of the arrangement of the disclosure is that it allows to set different pressures in the isolated enclosures reliably without extra process steps.
Claims20
A microelectromechanical system comprising:
- an ASIC layer comprising a control circuit;
- an interposer layer comprising a first side and a second side, wherein the ASIC layer is attached to the first side of the interposer layer;
- a MEMS layer comprising a first side and a second side, wherein the second side of the interposer layer is attached to the first side of the MEMS layer;
- and
- a cap layer attached to the second side of the MEMS layer,
- wherein the interposer layer and the cap layer form a first isolated enclosure with the MEMS layer inside, and the ASIC layer and the cap layer form a second isolated enclosure with the MEMS layer inside, wherein pressure in the first isolated enclosure is different from pressure in the second isolated enclosure,
- wherein the MEMS layer comprises a first movable structure and a second movable structure, and
- wherein the first movable structure is in the first isolated enclosure, and the second movable structure is located in the second isolated enclosure.
A method of fabricating a microelectromechanical system, comprising:
- forming an interposer layer on top of a first wafer;
- forming a MEMS layer from the first wafer, the MEMS layer comprising a first movable structure and a second movable structure;
- attaching a cap layer to the MEMS layer, to facilitate a first isolated enclosure is formed between the cap layer and the interposer layer, and setting pressure in the first isolated enclosure;
- removing a portion of the interposer layer over the second movable structure;
- attaching an ASIC layer to the interposer layer to facilitate a second isolated enclosure that is formed between the ASIC layer and the cap layer;
- and
- setting pressure in the second isolated enclosure.
Dependencies are inferred from the claim text.