In some examples, a device includes a nanovoided polymer element, a planarization layer disposed on a surface of the nanovoided polymer element, a first electrode disposed on the planarization layer, and a second electrode. The nanovoided polymer element may be located at least in part between the first electrode and the second electrode. The planarization layer may be located between the nanovoided polymer element and the first electrode.

A piezoelectric micromachined ultrasonic transducer (pMUT) device may include a piezoelectric membrane transducer designed to have lower sensitivity to residual stress and reduced sensitivity to geometric variations arising from the backside etching process used to release the membrane. These designs allow some of its key feature to be adjusted to achieve desired characteristics, such as pressure sensitivity, natural frequency, stress sensitivity, and bandwidth.

A microelectromechanical system (MEMS) resonator includes a degenerately-doped single-crystal silicon layer and a piezoelectric material layer disposed on the degenerately-doped single-crystal silicon layer. An electrically-conductive material layer is disposed on the piezoelectric material layer opposite the degenerately-doped single-crystal silicon layer, and patterned to form first and second electrodes.

Provided are a contact sensitive device, a display apparatus including the same, and a method of manufacturing the same. The contact sensitive device includes an electroactive layer formed of an electroactive polymer having a plurality of nano pores and an electrode disposed on at least one surface of the electroactive layer. The electroactive layer has a -phase structure and improved piezoelectricity without performing a stretching process or a polling process.

An element, including a first electrode, an intermediate layer, and a second electrode, the first electrode, the intermediate layer, and the second electrode being laminated in this order, wherein the intermediate layer has flexibility, and wherein a deformation amount on a side of the first electrode of the intermediate layer is different from a deformation amount on a side of the second electrode of the intermediate layer when a pressure is applied to the intermediate layer in a direction orthogonal to a surface of the intermediate layer.

A method for manufacturing a piezoelectric device that includes a substrate and a vibration portion that can include a membrane or a beam that is directly or indirectly supported by the substrate and arranged above the substrate. Moreover, the vibration portion includes a piezoelectric layer and the method includes forming the vibration portion and adjusting a resonance frequency of the vibration portion by locally subjecting a region including the vibration portion to heat treatment.

The teachings of the present disclosure enable the manufacture of one or more piezoelectric micromachined ultrasonic transducers (PMUTs) having a resonant frequency of a specific target value and/or substantially matched resonant frequencies. In accordance with the present disclosure, a flexible membrane of a PMUT is modified to impart a desired parameter profile for stiffness and/or mass to tune its resonant frequency to a target value. The desired parameter profile is achieved by locally removing or adding material to regions of one or more layers of the flexible membrane to alter its geometric dimensions and/or density. In some embodiments, material is added or removed non-uniformly across the structural layer to realize a material distribution that more strongly affects membrane stiffness than mass. In some embodiments, material having a specific residual stress is added to, and/or removed from, the membrane to define a desired modal stiffness for the membrane.

Provided are a touch sensitive element and a manufacturing method thereof. The manufacturing method for the touch sensitive element according to an embodiment of the present disclosure includes forming an electroactive polymer coating layer by applying an electroactive polymer solution on a substrate; forming an electroactive layer by heating and pressurizing the electroactive polymer coating layer using a hot press roller; and forming an electrode on the electroactive layer.

Methods, systems, and apparatus for using a two-dimensional distributed mode actuator. One of the systems includes a transducer adapted to create a force to cause vibration of a load to generate sound waves, the transducer having a first width along a first axis; a transfer portion connected to the transducer along a first side parallel to the first axis, and having a second width along the first axis that is less than the first width; and a stub connected to the transfer portion along a second side of the transfer portion that is parallel to the first axis and an opposite side from the first side connected to the transducer, having a third width that is greater than the second width, and having a surface adapted to connect to the load to transfer the force received from the transducer through the transfer portion to the load.

An element, including a first electrode, an intermediate layer, and a second electrode, the first electrode, the intermediate layer, and the second electrode being laminated in this order, wherein the intermediate layer has flexibility, and wherein a deformation amount on a side of the first electrode of the intermediate layer is different from a deformation amount on a side of the second electrode of the intermediate layer when a pressure is applied to the intermediate layer in a direction orthogonal to a surface of the intermediate layer.