A piezoelectric member including metal electrodes with improved adhesiveness to piezoelectric elements is to be provided. A piezoelectric member 102 includes a piezoelectric element 21, and a pair of electrodes 41, 42 respectively formed on a pair of opposing surfaces 21b, 21c of the piezoelectric element 21. The electrodes 41, 42 includes: a base film 41a that is formed on the opposing surfaces 21b, 21c of the piezoelectric element 21 and contains a thiol group; a metal adhesive film 41b formed on the base film 41a; and an electrode film 41c that is formed on the metal adhesive film 41b and is for applying voltage to the piezoelectric element 21. The metal adhesive film 41b is formed with a different material from the electrode film 41c, and has a thickness of 1 to 10 nm.

A piezoelectric laminate and a piezoelectric element have, on a substrate in the following order, a lower electrode layer and a piezoelectric film containing a perovskite-type oxide. The lower electrode layer includes a second layer arranged in a state of being in contact with the piezoelectric film and includes a first layer arranged on a side of the second layer from the substrate, where the first layer contains one or more of W, Mo, Nb, and Ta, as a main component, and the second layer contains Ir as a main component, where the thickness of the second layer is 50 nm or less.

A method of forming a piezoelectric thin film includes sputtering a first surface of a substrate to provide a piezoelectric thin film comprising AlN, AlScN, AlCrN, HfMgAlN, or ZrMgAlN thereon, processing a second surface of the substrate that is opposite the first surface of the substrate to provide an exposed surface of the piezoelectric thin film from beneath the second surface of the substrate, wherein the exposed surface of the piezoelectric thin film includes a first crystalline quality portion, removing a portion of the exposed surface of the piezoelectric thin film to access a second crystalline quality portion that is covered by the first crystalline quality portion, wherein the second crystalline quality portion has a higher quality than the first crystalline quality portion and processing the second crystalline quality portion to provide an acoustic resonator device on the second crystalline quality portion.

A method of manufacturing a vibration element includes: a first protective film forming step of forming a first protective film on a first substrate surface of a crystal substrate; a first dry etching step of dry-etching the crystal substrate via the first protective film; a second protective film forming step of forming a second protective film on a second substrate surface of the crystal substrate; and a second dry etching step of dry-etching the crystal substrate via the second protective film. A relationship of T1<T2<T3 or T4<T5<T6 is satisfied, in which T1 and T4 are thicknesses of the first and second protective films in an inter-arm region, respectively, T2 and T5 are thicknesses of the first and second protective films in first and second groove forming regions, respectively, and T3 and T6 are thicknesses of the first and second protective films in first and second bank portion forming regions, respectively.

A method of manufacturing a vibration element includes: a first protective film forming step of forming a first protective film on a first substrate surface of a crystal substrate; a first dry etching step of dry-etching the crystal substrate via the first protective film; a second protective film forming step of forming a second protective film on a second substrate surface of the crystal substrate; and a second dry etching step of dry-etching the crystal substrate via the second protective film. A relationship of T1<T2<T3 or T4<T5<T6 is satisfied, in which T1 and T4 are thicknesses of the first and second protective films in an inter-arm region, respectively, T2 and T5 are thicknesses of the first and second protective films in first and second groove forming regions, respectively, and T3 and T6 are thicknesses of the first and second protective films in first and second bank portion forming regions, respectively.

An integrated circuit film bulk acoustic resonator (FBAR) device having multiple resonator thicknesses is formed on a common substrate in a stacked configuration. In an embodiment, a seed layer is deposited on a substrate, and one or more multi-layer stacks are deposited on the seed layer, each multi-layer stack having a first metal layer deposited on a first sacrificial layer, and a second metal layer deposited on a second sacrificial layer. The second sacrificial layer can be removed and the resulting space is filled in with a piezoelectric material, and the first sacrificial layer can be removed to release the piezoelectric material from the substrate and suspend the piezoelectric material above the substrate. More than one multi-layer stack can be added, each having a unique resonant frequency. Thus, multiple resonator thicknesses can be achieved on a common substrate, and hence, multiple resonant frequencies on that same substrate.

Various embodiments of the present disclosure are directed towards an integrated circuit (IC) chip in which a pad barrier layer caps a pad of a piezoelectric device. The pad barrier layer is configured to block hydrogen ions and/or other errant materials from diffusing to the piezoelectric layer. Absent the pad barrier layer, hydrogen ions from hydrogen-ion containing processes performed after forming the pad may diffuse to the piezoelectric layer along a via extending from the pad to the piezoelectric device. By blocking diffusion of hydrogen ions and/or other errant materials to the piezoelectric device, the pad barrier layer may prevent delamination and breakdown of the piezoelectric layer. Hence, the pad barrier layer may prevent failure of the piezoelectric device.

A resonator includes a substrate, an acoustic Bragg mirror disposed above the substrate, and a bottom metal layer disposed above the acoustic Bragg mirror. The resonator also includes a piezoelectric plate disposed above the bottom metal layer. The resonator further includes a top metal layer disposed above the piezoelectric plate. The top metal layer comprises multiple fingers within a single plane and the width of each of the fingers is between 75%-125% of a thickness of the piezoelectric plate.

A piezoelectric element includes a piezoelectric body including a piezoelectric material, and a first electrode and a second electrode provided on the piezoelectric body. The piezoelectric body includes a base and a plurality of drivers. The base includes a first main surface and a second main surface opposing each other. The plurality of drivers is arranged on the first main surface in such a way as to be separate from each other. Each of the plurality of drivers includes a third main surface contacting the first main surface and a fourth main surface opposing the third main surface. The base includes a plurality of first regions in which the plurality of drivers is provided and a second region provided between the first regions adjacent to each other. The base is curved.

A method for making a piezoelectric microelectromechanical systems (MEMS) microphone is provided, comprising depositing a piezoelectric film layer onto a substrate; selectively etching the piezoelectric film layer to define lines; removing the substrate to define a cavity; and breaking the piezoelectric film layer along the lines, such that the microphone has at least two cantilevered beams. The piezoelectric microelectromechanical systems (MEMS) microphone is also provided.