A method of manufacture for an acoustic resonator or filter device. In an example, the present method can include forming metal electrodes with different geometric areas and profile shapes coupled to a piezoelectric layer overlying a substrate. These metal electrodes can also be formed within cavities of the piezoelectric layer or the substrate with varying geometric areas. Combined with specific dimensional ratios and ion implantations, such techniques can increase device performance metrics. In an example, the present method can include forming various types of perimeter structures surrounding the metal electrodes, which can be on top or bottom of the piezoelectric layer. These perimeter structures can use various combinations of modifications to shape, material, and continuity. These perimeter structures can also be combined with sandbar structures, piezoelectric layer cavities, the geometric variations previously discussed to improve device performance metrics.

A method of manufacture for an acoustic resonator or filter device. In an example, the present method can include forming metal electrodes with different geometric areas and profile shapes coupled to a piezoelectric layer overlying a substrate. These metal electrodes can also be formed within cavities of the piezoelectric layer or the substrate with varying geometric areas. Combined with specific dimensional ratios and ion implantations, such techniques can increase device performance metrics. In an example, the present method can include forming various types of perimeter structures surrounding the metal electrodes, which can be on top or bottom of the piezoelectric layer. These perimeter structures can use various combinations of modifications to shape, material, and continuity. These perimeter structures can also be combined with sandbar structures, piezoelectric layer cavities, the geometric variations previously discussed to improve device performance metrics.

A method of manufacture for an acoustic resonator or filter device. In an example, the present method can include forming metal electrodes with different geometric areas and profile shapes coupled to a piezoelectric layer overlying a substrate. These metal electrodes can also be formed within cavities of the piezoelectric layer or the substrate with varying geometric areas. Combined with specific dimensional ratios and ion implantations, such techniques can increase device performance metrics. In an example, the present method can include forming various types of perimeter structures surrounding the metal electrodes, which can be on top or bottom of the piezoelectric layer. These perimeter structures can use various combinations of modifications to shape, material, and continuity. These perimeter structures can also be combined with sandbar structures, piezoelectric layer cavities, the geometric variations previously discussed to improve device performance metrics.

The method for fabricating a FBAR provided according to the present invention includes providing a substrate, forming a dielectric material layer on a surface of the substrate away from the substrate, forming a bottom electrode on a surface of the dielectric material layer away from the substrate, forming a piezoelectric material layer on a surface of the bottom electrode away from the substrate, forming an intermediate metal layer on a surface of the piezoelectric material layer away from the substrate, forming a mass load layer on a surface of the intermediate metal layer away from the substrate, and forming a top electrode on a surface of the mass load layer away from the substrate. In this way, process choices are increased, and flexibility in multiple mass load formation of the FBAR below top electrode and in a filter having the FBARs are increased, thereby improving sensitivity in the filter.

A method of manufacturing a piezoelectric resonator unit that includes mounting a piezoelectric resonator on a base member using a conductive adhesive, keeping the piezoelectric resonator in an environment having a temperature and a humidity higher than those of a surrounding region for a predetermined time, performing frequency adjustment of the piezoelectric resonator by etching using an ion beam, and joining a lid member to the base member using a joining material such that the piezoelectric resonator is hermetically sealed between the lid member and the base member.

A method for manufacturing a quartz crystal resonator that includes a quartz crystal blank having a vibrating portion including a center of a principal surface of the quartz crystal blank when viewed in plan from a direction normal to the principal surface and a peripheral portion adjacent to the vibrating portion, a pair of excitation electrodes disposed opposite to each other with the vibrating portion interposed therebetween, a pair of electrode pads disposed on the peripheral portion, and a pair of extended electrodes each extending from the vibrating portion to the peripheral portion to electrically connect one excitation electrode to a corresponding electrode pad, where the method includes conducting a first trimming of the vibrating portion and the peripheral portion; and conducting a second trimming of part of one of the excitation electrodes on the vibrating portion.

A crystal resonator vibrates in a thickness-shear mode. The crystal resonator includes excitation electrodes being disposed on a front surface and a back surface of a crystal element. The excitation electrodes are disposed on the crystal element to have a positional relationship, where a displacement distribution at an edge of the excitation electrode on the front surface is identical to a displacement distribution at an edge of the excitation electrode on the back surface.

In a method for adjusting a frequency of a crystal resonator, a frequency adjustment metal film made of a base metal layer and a metal layer laminated thereon is formed on a first main surface of a second sealing member on a side facing a second excitation electrode. The second sealing member is made of crystal. The frequency adjustment metal film is irradiated with a laser from the outside of the second sealing member so that the laser penetrates the interior of the second sealing member and heats the base metal layer. Then, at least part of the metal layer is melted and evaporated, and the evaporated metal is adhered to the second excitation electrode. Thus, the frequency adjustment is performed.

A bulk acoustic wave (BAW) resonator includes a substrate defining a cavity, a bottom electrode disposed over the substrate and the cavity, a piezoelectric layer disposed on the bottom electrode, and a top electrode disposed on the piezoelectric layer. The piezoelectric layer includes polycrystalline lithium niobate (LN) material or polycrystalline lithium tantalite (LT) material. The BAW resonator may further include an encapsulant layer formed on side and top surfaces of the piezoelectric layer. The encapsulant layer is configured to protect the LN material or the LT material of the piezoelectric layer from a release solvent previously applied to sacrificial material within the cavity in the substrate.

A method of tuning the resonant frequency of embedded bulk acoustic resonators during manufacturing of an integrated circuit. The rate of change in the resonant frequency of BAWs vs rate of change in top electrode thickness is determined and used to tune the resonant frequency of embedded bulk acoustic resonators during integrated circuit manufacturing.