Micro-electro-mechanical system (MEMS) devices are disclosed, including a MEMS device comprising a semiconductor die including integrated circuitry, a structure mounted on the semiconductor die and covering at least a portion of the circuitry, the structure defining a space between the structure and the at least a portion of the circuitry, and a transducer including a membrane, the transducer located outside of the space.

In a non-limiting embodiment, a MEMS device may include a substrate having a device stopper. The device stopper may be integral to the substrate and formed of the substrate material. A thermal dielectric isolation layer may be arranged over the device stopper and the substrate. A device cavity may extend through the substrate and the thermal dielectric isolation layer. The thermal dielectric isolation layer and the device stopper at least partially surround the device cavity. An active device layer may be arranged over the thermal dielectric isolation layer and the device cavity.

For manufacturing an optical microelectromechanical device, a first wafer of semiconductor material having a first surface and a second surface is machined to form a suspended mirror structure, a fixed structure surrounding the suspended mirror structure, elastic supporting elements which extend between the fixed structure and the suspended mirror structure, and an actuation structure coupled to the suspended mirror structure. A second wafer is machined separately to form a chamber delimited by a bottom wall having a through opening. The second wafer is bonded to the first surface of the first wafer in such a way that the chamber overlies the actuation structure and the through opening is aligned to the suspended mirror structure. Furthermore, a third wafer is bonded to the second surface of the first wafer to form a composite wafer device. The composite wafer device is then diced to form an optical microelectromechanical device.

In a non-limiting embodiment, a MEMS device may include a substrate having a device stopper. The device stopper may be integral to the substrate and formed of the substrate material. A thermal dielectric isolation layer may be arranged over the device stopper and the substrate. A device cavity may extend through the substrate and the thermal dielectric isolation layer. The thermal dielectric isolation layer and the device stopper at least partially surround the device cavity. An active device layer may be arranged over the thermal dielectric isolation layer and the device cavity.

A micro electro mechanical system (MEMS) includes a circuit substrate comprising electronic circuitry, a support substrate having a recess, a bonding layer disposed between the circuit substrate and the support substrate, through holes passing through the circuit substrate to the recess, a first conductive layer disposed on a front side of the circuit substrate, and a second conductive layer disposed on an inner wall of the recess. The first conductive layer extends into the through holes and the second conductive layer extends into the through holes and coupled to the first conductive layer.

A micro-electromechanical device includes a semiconductor substrate, in which a first microstructure and a second microstructure of reference are integrated. The first microstructure and the second microstructure are arranged in the substrate so as to undergo equal strains as a result of thermal expansions of the substrate. Furthermore, the first microstructure is provided with movable parts and fixed parts with respect to the substrate, while the second microstructure has a shape that is substantially symmetrical to the first microstructure but is fixed with respect to the substrate. By subtracting the changes in electrical characteristics of the second microstructure from those of the first, variations in electrical characteristics of the first microstructure caused by changes in thermal expansion or contraction can be compensated for.

A method of manufacturing an electromechanical systems structure includes manufacturing sub-micron structural features. In some embodiments, the structural features are less than the lithographic limit of a lithography process.

Suspended microelectromechanical systems (MEMS) devices including a stack of one or more materials over a cavity in a substrate are described. The suspended MEMS device may be formed by forming the stack, which may include one or more electrode layers and an active layer, over the substrate and removing part of the substrate underneath the stack to form the cavity. The resulting suspended MEMS device may include one or more channels that extend from a surface of the device to the cavity and the one or more channels have sidewalls with a spacer material. The cavity may have rounded corners and may extend beyond the one or more channels to form one or more undercut regions. The manner of fabrication may allow for forming the stack layers with a high degree of planarity.

Disclosed is a method of fabricating a MEMS membrane structure. The method comprises: forming a silicon oxide film dam structure on a silicon substrate; depositing an adhesive layer and then forming a sacrificial layer; depositing a surface protective film on the sacrificial layer; etching the surface protective film and the sacrificial layer, thus forming trenches of first to third rows on the silicon oxide film dam structure; depositing a support film inside of the trenches of first to third rows and on the surface protective film of the sacrificial layer, thus forming a membrane; and removing the sacrificial layer disposed inside the support film deposited inside of the trench of first row, thus forming an empty space.

A MEMS IR sensor, with a cavity in a substrate underlapping an overlying layer and a temperature sensing component disposed in the overlying layer over the cavity, may be formed by forming an IR-absorbing sealing layer on the overlying layer so as to cover access holes to the cavity. The sealing layer is may include a photosensitive material, and the sealing layer may be patterned using a photolithographic process to form an IR-absorbing seal. Alternately, the sealing layer may be patterned using a mask and etch process to form the IR-absorbing seal.