A micromechanical z-inertial sensor having a movable MEMS structure developed in a second function layer; first spring elements developed in a first function layer, and a first electrode developed in the first function layer, the first spring elements being connected to the movable MEMS structure and to a substrate, and the first function layer being situated below the second function layer; second spring elements developed in a third function layer, and a second electrode developed in the third function layer, the second spring elements being connected to the movable MEMS structure and to the substrate, and the third function layer being disposed above the second function layer; the movable MEMS structure being deflectable in the z-direction with the aid of the spring elements, and in a defined manner, not being deflectable in the x- and y-directions.

A recess is formed in one silicon substrate. A silicon oxide film is formed in another one silicon substrate at a portion space apart from a space-to-be-formed region. The silicon oxide film has a groove surrounding the space-to-be-formed region and extending to an outer periphery of the other one silicon substrate. Further, the other one silicon substrate and the one silicon substrate are directly bonded to each other via the silicon oxide film so as to cover the groove. A gas discharge passage, a stacking structure of the silicon substrates and the silicon oxide film are formed, and the space is formed inside the stacking structure by the recess. Then, by the heat treatment, the gas inside the space is discharged to the outside of the stacking structure through the gas discharge passage.

A method for producing a thin-film layer includes providing a layer stack on a carrier substrate, wherein the layer stack includes a carrier layer and a sacrificial layer, and wherein the sacrificial layer includes areas in which the carrier layer is exposed. The method includes providing the thin-film layer on the layer stack, such that the thin-film layer bears on the sacrificial layer and, in the areas of the sacrificial layer in which the carrier layer is exposed, against the carrier layer. The method includes at least partly removing the sacrificial layer from the thin-film layer in order to eliminate a contact between the thin-film layer and the sacrificial layer in some areas. The method also includes detaching the thin-film layer from the carrier layer.

A method for producing a thin-film layer includes providing a layer stack on a carrier substrate, wherein the layer stack includes a carrier layer and a sacrificial layer, and wherein the sacrificial layer includes areas in which the carrier layer is exposed. The method includes providing the thin-film layer on the layer stack, such that the thin-film layer bears on the sacrificial layer and, in the areas of the sacrificial layer in which the carrier layer is exposed, against the carrier layer. The method includes at least partly removing the sacrificial layer from the thin-film layer in order to eliminate a contact between the thin-film layer and the sacrificial layer in some areas. The method also includes detaching the thin-film layer from the carrier layer.

A method of forming a microelectromechanical device wherein a beam of the microelectromechanical device may deviate from a resting to an engaged or disengaged position through electrical biasing. The microelectromechanical device comprises a beam disposed above a first RF electrode and a second RF electrode. The microelectromechanical device further comprises one or more electrical contacts disposed below the beam. The one or more electrical contacts comprise a first layer of ruthenium disposed over an oxide layer, a titanium nitride layer disposed on the first layer of ruthenium, and a second layer of ruthenium disposed on the titanium nitride layer.

A method of forming a microelectromechanical device wherein a beam of the microelectromechanical device may deviate from a resting to an engaged or disengaged position through electrical biasing. The microelectromechanical device comprises a beam disposed above a first RF conductor and a second RF conductors. The microelectromechanical device further comprises at least a center stack, a first RF stack, a second RF stack, a first stack formed on a first base layer, and a second stack formed on a second base layer, each stack disposed between the beam and the first and second RF conductors. The beam is configured to deflect downward to first contact the first stack formed on the first base layer and the second stack formed on the second base layer simultaneously or the center stack, before contacting the first RF stack and the second RF stack simultaneously.

A method of forming a microelectromechanical device wherein a beam of the microelectromechanical device may deviate from a resting to an engaged or disengaged position through electrical biasing. The microelectromechanical device comprises a beam disposed above a first RF conductor and a second RF conductor. The microelectromechanical device further comprises at least a center stack, a first RF stack, a second RF stack, a first stack formed on a first base layer, and a second stack formed on a second base layer, each stack disposed between the beam and the first and second RF conductors. The beam is configured to deflect downward to first contact the first stack formed on the first base layer and the second stack formed on the second base layer simultaneously or the center stack, before contacting the first RF stack and the second RF stack simultaneously.

A MEMS device includes a lower substrate having a resonator, an upper substrate disposed to oppose an upper electrode of the resonator, a bonding layer sealing an internal space between the lower substrate and the upper substrate, and wiring layers that contain the same metal material as the bonding layer. Moreover, a rare gas content of each of the wiring layers is less than 110.sup.20 (atoms/cm.sup.3).

In some embodiments, the present disclosure relates to a method for forming a microelectromechanical system (MEMS) device, including depositing a first electrode layer over a first piezoelectric layer. A hard mask layer is then deposited over the first electrode layer. A photoresist mask is formed on the hard mask layer with a first-electrode pattern. Using the photoresist mask, a first etch is performed into the hard mask layer to transfer the first-electrode pattern to the hard mask layer. The photoresist mask is then removed. A second etch is performed using the hard mask layer to transfer the first-electrode pattern to the first electrode layer, and the hard mask layer is removed.

Embodiments of the disclosure provide a micromachined mirror assembly having a mirror-base layer, a first reflective layer on a top surface of the mirror-base layer, and a second reflective layer on a bottom surface of the mirror-base layer. In an example, the first reflective layer is reflective to incident light of the micromachined mirror assembly, and the first reflective layer and the second reflective layer are made of a same material and have same dimensions.