A micromachined ultrasonic transducer (MUT). The MUT includes: a substrate; a membrane suspending from the substrate; a bottom electrode disposed on the membrane; a piezoelectric layer disposed on the bottom electrode and an asymmetric top electrode is disposed on the piezoelectric layer. The areal density distribution of the asymmetric electrode along an axis has a plurality of local maxima, wherein locations of the plurality of local maxima coincide with locations where a plurality of anti-nodal points at a vibrational resonance frequency is located.

A micromachined ultrasonic transducer (MUT). The MUT includes: a substrate; a membrane suspending from the substrate; a bottom electrode disposed on the membrane; a piezoelectric layer disposed on the bottom electrode and an asymmetric top electrode is disposed on the piezoelectric layer. The areal density distribution of the asymmetric electrode along an axis has a plurality of local maxima, wherein locations of the plurality of local maxima coincide with locations where a plurality of anti-nodal points at a vibrational resonance frequency is located.

An electrical device comprises a substrate, a first dielectric layer, a first die, an adjustable inductor and a second die. The substrate has a first surface. The first dielectric layer is disposed on the first surface of the substrate and has a first surface. The first die is surrounded by the first dielectric layer. The adjustable inductor is electrically connected to the first die. The adjustable inductor comprises a plurality of pillars surrounded by the first dielectric layer, a plurality of first metal strips disposed on the first surface of the first dielectric layer and electrically connected to the pillars, and a plurality of second metal strips disposed on the first surface of the first dielectric layer and electrically connected to the pillars. A width of at least one of the second metal strips is different than a width of at least one of the first metal strips. The second die is electrically connected to the adjustable inductor.

An electrical device comprises a substrate, a first dielectric layer, a first die, an adjustable inductor and a second die. The substrate has a first surface. The first dielectric layer is disposed on the first surface of the substrate and has a first surface. The first die is surrounded by the first dielectric layer. The adjustable inductor is electrically connected to the first die. The adjustable inductor comprises a plurality of pillars surrounded by the first dielectric layer, a plurality of first metal strips disposed on the first surface of the first dielectric layer and electrically connected to the pillars, and a plurality of second metal strips disposed on the first surface of the first dielectric layer and electrically connected to the pillars. A width of at least one of the second metal strips is different than a width of at least one of the first metal strips. The second die is electrically connected to the adjustable inductor.

A micromachined ultrasonic transducer (MUT). The MUT includes: a substrate; a membrane suspending from the substrate; a bottom electrode disposed on the membrane; a piezoelectric layer disposed on the bottom electrode and an asymmetric top electrode is disposed on the piezoelectric layer. The areal density distribution of the asymmetric electrode along an axis has a plurality of local maxima, wherein locations of the plurality of local maxima coincide with locations where a plurality of anti-nodal points at a vibrational resonance frequency is located.

A micromachined ultrasonic transducer (MUT). The MUT includes: a substrate; a membrane suspending from the substrate; a bottom electrode disposed on the membrane; a piezoelectric layer disposed on the bottom electrode and an asymmetric top electrode is disposed on the piezoelectric layer. The areal density distribution of the asymmetric electrode along an axis has a plurality of local maxima, wherein locations of the plurality of local maxima coincide with locations where a plurality of anti-nodal points at a vibrational resonance frequency is located.

Systems, devices, and methods for micro-electro-mechanical system (MEMS) tunable capacitors can include a fixed actuation electrode attached to a substrate, a fixed capacitive electrode attached to the substrate, and a movable component positioned above the substrate and movable with respect to the fixed actuation electrode and the fixed capacitive electrode. The movable component can include a movable actuation electrode positioned above the fixed actuation electrode and a movable capacitive electrode positioned above the fixed capacitive electrode. At least a portion of the movable capacitive electrode can be spaced apart from the fixed capacitive electrode by a first gap, and the movable actuation electrode can be spaced apart from the fixed actuation electrode by a second gap that is larger than the first gap.

A variable capacitor includes an enclosure having first and second conductive collars separated by an intermediate electrically insulating element. A movable capacitor plate assembly is electrically coupled to the first conductive collar, and a fixed capacitor plate assembly is electrically coupled to the second conductive collar. An actuator extends into the enclosure for advancing and retracting the movable capacitor plate assembly relative to the fixed capacitor plate assembly. A hermetically sealed volume within the enclosure maintains a vacuum or a liquid serving as a dielectric between a capacitor plate of the movable capacitor plate assembly and a capacitor plate of the fixed capacitor plate assembly. At least one capacitor plate comprises a coiled cylindrical plate having a having a greater height at a center portion of the capacitor plate coil and a lower height at an outer portion of the capacitor plate coil.

An electrical device comprises a substrate, a first dielectric layer, a first die, an adjustable inductor and a second die. The substrate has a first surface. The first dielectric layer is disposed on the first surface of the substrate and has a first surface. The first die is surrounded by the first dielectric layer. The adjustable inductor is electrically connected to the first die. The adjustable inductor comprises a plurality of pillars surrounded by the first dielectric layer, a plurality of first metal strips disposed on the first surface of the first dielectric layer and electrically connected to the pillars, and a plurality of second metal strips disposed on the first surface of the first dielectric layer and electrically connected to the pillars. A width of at least one of the second metal strips is different than a width of at least one of the first metal strips. The second die is electrically connected to the adjustable inductor.

A method of forming a capacitor includes depositing a dielectric metal oxide layer of a first phase to a thickness no greater than 75 Angstroms over an inner conductive capacitor electrode material. The first phase dielectric metal oxide layer has a k of at least 15. Conductive RuO.sub.2 is deposited over and into physical contact with the dielectric metal oxide layer. Then, the RuO.sub.2 and the dielectric metal oxide layer are annealed at a temperature below 500 C. The RuO.sub.2 in physical contact with the dielectric metal oxide during the annealing facilitates a change of the dielectric metal oxide layer from the first phase to a second crystalline phase having a higher k than the first phase. The annealed dielectric metal oxide layer is incorporated into a capacitor dielectric region of a capacitor construction. Other implementations are disclosed.