Switchable and/or tunable filters, methods of manufacture and design structures are disclosed herein. The method of forming the filters includes forming at least one piezoelectric filter structure comprising a plurality of electrodes formed to be in contact with at least one piezoelectric substrate. The method further includes forming a micro-electro-mechanical structure (MEMS) comprising a MEMS beam in which, upon actuation, the MEMS beam will turn on the at least one piezoelectric filter structure by interleaving electrodes in contact with the piezoelectric substrate or sandwiching the at least one piezoelectric substrate between the electrodes.

A method of fabricating a resonator includes providing a first quartz substrate, forming a metallic etch stop on a first surface of the first quartz substrate; attaching, using a temporary adhesive, the first surface of the first quartz substrate to a second quartz substrate, etching an opening for a via in a second surface of the first quartz substrate to the metallic etch stop, forming a metal electrode on the second surface of the first quartz substrate, the metal electrode penetrating the via in the first quartz substrate to make ohmic contact with the metallic etch stop, bonding the metal electrode formed on the second surface of the first quartz substrate to a pad formed on a host substrate; and dissolving the temporary adhesive to release the second quartz substrate from the first quartz substrate, wherein the first quartz substrate and the host substrate each comprise crystalline quartz.

A rectangular quartz crystal blank having long sides substantially parallel to a Z axis of the quartz crystal blank, and short sides substantially parallel to an X axis of the quartz crystal blank. The quartz crystal blank includes a first center region, a second region and a third region that are adjacent to the first region along a long-side direction, and a fourth region and a fifth region that are adjacent to the first region along a short-side direction. A thickness of the second region and a thickness of the third region are smaller than a thickness of the first region, and/or a thickness of the fourth region and a thickness of the fifth region are smaller than the thickness of the first region, and 19.87W/T20.36, where W is a length of a short side and T is a thickness.

A quartz crystal unit that includes a quartz crystal resonator with a quartz crystal blank on which a pair of excitation electrodes are formed, a frame body that surrounds an outer periphery of the blank, and a coupling member that couples the frame body to the blank. Moreover, a package member is joined to an entire periphery of the frame body on at least one side of the excitation electrodes; and an extension electrode is provided that is electrically connected to one of the excitation electrodes. A recess is formed in a junction region of at least one of the frame body and the package member. In the junction region, the extension electrode is disposed in the recess in such a way that the extension electrode has a thickness that does not exceed a depth of the recess.

A piezoelectric oscillation device includes a piezoelectric vibration element, a heating element that heats the piezoelectric vibration element, an electronic component that is electrically connected to the piezoelectric vibration element, a substrate on which the piezoelectric vibrator, the heating element, and the electronic component are mounted, and a base member to which the substrate is attached with a prescribed spacing therebetween via a substrate holding member. The substrate holding member includes a conductive part. The conductive part has a lower thermal conductivity than metal.

A piezoelectric device includes a conductive adhesive, a container, and an AT-cut crystal element. The AT-cut crystal element has at least one side surface intersecting with a Z-axis of the crystallographic axis of the crystal constituted of three surfaces. When a dimension of a straight-line portion along the Z-axis of a second side opposed to the first side is expressed as W1 and a dimension along the Z-axis of the AT-cut crystal element is expressed as W0, W1/W0 is 0.91 or greater, and the straight-line portion has both sides constituting corner portions in approximately right angles with sides along an X-axis of the crystal of the AT-cut crystal element. The side of the first side is at a ?X-side in an X-axis of the crystallographic axis of the crystal and a side of the second side is at a +X-side in the X-axis.

A method for manufacturing a vibrator that includes forming excitation electrodes, lead-out electrodes, and first sealing frames on the main surfaces of a crystal piece; forming second sealing frames on the main surfaces of a base part and a lid part; and sealing a crystal vibration element by bonding the first sealing frames to the second sealing frames. The first sealing frames each include a first Ti or Cr base layer 110, and a first Au surface layer. The first Ti or Cr base layers are thinner than the first Au surface layers. The second sealing frames each include a second Ni base layer, and a second AuSn surface layer. The second Ni base layers are thicker than the second AuSn surface layers. The sealing is carried out by alloying the first Au surface layers and the second AuSn surface layers to each other.

A method of manufacturing a resonator element including a substrate having a thin-wall part and a thick-wall part, and an electrode part having an excitation electrode arranged in an excitation electrode placement area of the thin-wall part, a pad electrode arranged in a pad electrode placement area of the thick-wall part, and an extraction electrode which is configured to couple the excitation electrode and the pad electrode to each other, and which is arranged in an extraction electrode placement area of the substrate, includes a metal layer formation step of forming a metal layer on the substrate, a protective film formation step of forming a protective film in an area overlapping at least a part of the extraction electrode placement area in a plan view on the metal layer, and a metal layer etching step of etching the metal layer arranged in the excitation electrode placement area via the protective film to thereby reduce a wall thickness of the metal layer.

A method of manufacturing a quartz crystal element includes preparing a quartz crystal wafer having a predetermined cutting angle with respect to a crystal axis of a quartz crystal, forming a first resist film having a first tilted part on a first surface of the quartz crystal wafer and dry-etching the first resist film with the quartz crystal, forming a first tilted surface by dry-etching the quartz crystal wafer from the first surface side, forming a second resist film having a second tilted part on a second surface of the quartz crystal wafer and dry-etching the second resist film with the quartz crystal, and forming a second tilted surface tilted by dry-etching the quartz crystal wafer from the second surface side. The quartz crystal element provided with the first tilted surface and the second tilted surface, and having a cutting angle different from the predetermined cutting angle is formed.

Switchable and/or tunable filters, methods of manufacture and design structures are disclosed herein. The method of forming the filters includes forming at least one piezoelectric filter structure comprising a plurality of electrodes formed to be in contact with at least one piezoelectric substrate. The method further includes forming a micro-electro-mechanical structure (MEMS) comprising a MEMS beam in which, upon actuation, the MEMS beam will turn on the at least one piezoelectric filter structure by interleaving electrodes in contact with the piezoelectric substrate or sandwiching the at least one piezoelectric substrate between the electrodes.