A method and apparatus are described for fabricating a high aspect ratio MEMS sensor device having an inertial transducer element formed in a multi-layer semiconductor structure, where the first inertial transducer element comprises a first monocrystalline semiconductor proof mass element and a second conductive electrode element separated from one another by an air sensing gap, and where at least a first sensing gap surface of the first monocrystalline semiconductor proof mass element is a first rough surface that has been selectively etched to reduce stiction between the first monocrystalline semiconductor proof mass element and the second conductive electrode element.

Material structures and methods for etching hexagonal, single-crystal silicon carbide (SiC) materials are provided, which include selection of on-axis or near on-axis hexagonal single-crystal SiC material as the material to be etched. The methods include etching of SiC bulk substrate material, etching of SiC material layers bonded to a silicon oxide layer, etching of suspended SiC material layers, and etching of a SiC material layer anodically bonded to a glass layer. Plasma-etched hexagonal single-crystal SiC materials of the invention may be used to form structures that include, but are not limited to, microelectromechanical beams, microelectromechanical membranes, microelectromechanical cantilevers, microelectromechanical bridges, and microelectromechanical field effect transistor devices. The material structures and methods of the invention beneficially provide improved etch symmetry, improved etch straightness, improved sidewall straightness, improved sidewall smoothness, and reduced sidewall wander compared to etched four degree off-axis SiC materials.

A liquid ejection chip has a first flow channel substrate and a second flow channel substrate bonded to each other by using an adhesive, the first flow channel substrate having an energy generation element configured to generate energy for ejecting liquid and a first flow channel configured to supply the liquid to the energy generation element, the second flow channel substrate having a second flow channel connecting to the first flow channel. Recess portions are formed at each of a wall surface of the first flow channel and a wall surface of the second flow channel, and in terms of at least one of depth and width of the recess portions, the first flow channel substrate>the second flow channel substrate.

Deep via technology is used to construct an integrated silicon cantilever and cavity oriented in a vertical plane which creates an electrostatically-switched MEMS switch in a small wafer area. Another embodiment is a small wafer area electrostatically-switched, vertical-cantilever MEMS switch wherein the switch cavity is etched within a volume defined by walls grown internally within a silicon substrate using through vias.

Deep via technology is used to construct an integrated silicon cantilever and cavity oriented in a vertical plane which creates an electrostatically-switched MEMS switch in a small wafer area. Another embodiment is a small wafer area electrostatically-switched, vertical-cantilever MEMS switch wherein the switch cavity is etched within a volume defined by walls grown internally within a silicon substrate using through vias.

A system and method for manipulating the structural characteristics of a MEMS device include etching a plurality of holes into the surface of a MEMS device, wherein the plurality of holes comprise one or more geometric shapes determined to provide specific structural characteristics desired in the MEMS device.

Deep via technology is used to construct an integrated silicon cantilever and cavity oriented in a vertical plane which creates an electrostatically-switched MEMS switch in a small wafer area. Another embodiment is a small wafer area electrostatically-switched, vertical-cantilever MEMS switch wherein the switch cavity is etched within a volume defined by walls grown internally within a silicon substrate using through vias.

A producing method for a diaphragm-type resonant MEMS device includes forming a first silicon oxide film, forming a second silicon oxide film, forming a lower electrode, forming a piezoelectric film, forming an upper electrode, laminating the first silicon oxide film, the second silicon oxide film, the lower electrode, the piezoelectric film, and the upper electrode in this order on a first surface of a silicon substrate, and etching the opposite side surface of the first surface of the silicon substrate by deep reactive ion etching to form a diaphragm structure, in which the proportion R.sub.2 of the film thickness t.sub.2 of the second silicon oxide film with respect to the sum of the film thickness t.sub.1 of the first silicon oxide film and the film thickness t.sub.2 of the second silicon oxide film satisfies the following condition:
0.10 mt.sub.12.00 m; and
R.sub.20.70.

Deep via technology is used to construct an integrated silicon cantilever and cavity oriented in a vertical plane which creates an electrostatically-switched MEMS switch in a small wafer area. Another embodiment is a small wafer area electrostatically-switched, vertical-cantilever MEMS switch wherein the switch cavity is etched within a volume defined by walls grown internally within a silicon substrate using through vias.

A system and method for manipulating the structural characteristics of a MEMS device include etching a plurality of holes into the surface of a MEMS device, wherein the plurality of holes comprise one or more geometric shapes determined to provide specific structural characteristics desired in the MEMS device.