Patent ID: 12255599

DETAILED DESCRIPTION OF EMBODIMENTS

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. The drawings of each embodiment are examples, and dimensions and shapes of respective portions are schematic, and the technical scope of the present invention should not be understood as being limited to the embodiments.

In the following description, a quartz crystal resonator unit provided with a quartz crystal resonator will be taken as an example of a piezoelectric resonator unit for description. The quartz crystal resonator uses a quartz crystal element as a piezoelectric body excited by a piezoelectric effect.

It is noted that the piezoelectric element according to the exemplary embodiments is not limited to a quartz crystal element. The piezoelectric element may be formed of any piezoelectric material such as a piezoelectric single crystal, piezoelectric ceramics, a piezoelectric thin film, or a piezoelectric polymer film. For example, the piezoelectric single crystal may include lithium niobate (LiNbO3). Similarly, examples of the piezoelectric ceramics may include barium titanate (BaTiO3), lead titanate (PbTiO3), lead zirconate titanate (Pb(ZrxTi1-x) O3; PZT), aluminum nitride (AlN), lithium niobate (LiNbO3), lithium metaniobate (LiNb2O6), bismuth titanate (Bi4Ti3O12), lithium tantalate (LiTaO3), lithium tetraborate (Li2B4O7), langasite (La3Ga5SiO14), and tantalum pentoxide (Ta2O5). Examples of the piezoelectric thin film may include a film formed by depositing the piezoelectric ceramics on a substrate such as quartz or sapphire by a sputtering method or the like. Examples of the piezoelectric polymer film may include polylactic acid (PLA), polyvinylidene fluoride (PVDF), and a vinylidene fluoride/trifluoroethylene (VDF/TrFE) copolymer. The various piezoelectric materials described above may be laminated on each other or may be laminated on another member as would be appreciated to one skilled in the art.

First Exemplary Embodiment

First, a configuration of a quartz crystal resonator unit100according to a first exemplary embodiment will be described with reference toFIGS.1to3.FIG.1is a perspective view schematically illustrating a configuration of a quartz crystal resonator unit according to the first embodiment.FIG.2is a perspective view schematically illustrating a configuration of a laminated structure according to the first embodiment.FIG.3is a sectional view schematically illustrating the configuration of the quartz crystal resonator unit according to the first embodiment. The sectional view illustrated inFIG.3is taken along line III-III illustrated inFIGS.1and2.

In each of the drawings, an orthogonal coordinate system including the X-axis, the Y′-axis, and the Z′-axis may be illustrated for convenience in order to clarify a relationship between each of the drawings and to help understand a positional relationship between each of the members. The X-axis, the Y′-axis, and the Z′-axis respectively correspond to those in the drawings. The X-axis, the Y′-axis, and the Z′-axis respectively correspond to crystallographic axes of a quartz crystal element11to electrical axis (polar axis), the Y-axis corresponds to a mechanical axis, and the Z-axis corresponds to an optical axis be described later, and the X-axis corresponds to a lengthwise direction of the exemplary resonator. The Y′-axis and the Z′-axis are the axes obtained by respectively rotating the Y-axis and the Z-axis around the X-axis in the direction from the Y-axis to the Z-axis by 35 degrees 15 minutes±1 minute 30 seconds. In the following description, a direction parallel to the X-axis is referred to as the “X-axis direction”, a direction parallel to the Y′-axis is referred to as the “Y′-axis direction”, and a direction parallel to the Z′-axis is referred to as the “Z′-axis direction”. In addition, a tip direction of an arrow of the X-axis, the Y′-axis, and the Z′-axis is referred to as “+ (plus)”, and a direction opposite to the arrow is referred to as “− (minus)”.

As shown, the quartz crystal resonator unit100includes a laminated structure101, a base member30(also referred to as a “base”), a bonding member50, and a cover member40(also referred to as a “cover”). The laminated structure101is provided between the base member30and the cover member40. In the example illustrated inFIGS.1and2, the laminated structure101is mounted on the base member30. The base member30and the cover member40form an enclosure for accommodating the laminated structure101. In the example illustrated inFIGS.1and2, the base member30has a flat-plate shape, and the cover member40has a bottomed cavity that accommodates the laminated structure101on a side of the base member30. As long as at least a vibrating portion of the laminated structure101is accommodated in the enclosure, a method for enclosing the laminated structure101and the shapes of the base member30and the cover member40are not limited to those described above. For example, the base member30may have a bottomed cavity that accommodates the laminated structure101on a side of the cover member40. In addition, the base member30and the cover member40may have a flat-plate shape or a concave shape that opens toward the laminated structure101and may sandwich a peripheral portion of the vibrating portion of the laminated structure101.

The laminated structure101includes a quartz crystal resonator10and a temperature detection unit20. The quartz crystal resonator10and the temperature detection unit20are laminated in the Z-axis direction, and the quartz crystal resonator10is provided on a base member30side of the temperature detection unit20. In addition, when viewed in a plan view in the +Y′-axis direction, the laminated structure101includes a vibrating portion101aincluding a portion of the quartz crystal resonator10that is excited and a peripheral portion101blocated at an outer side portion of the vibrating portion101a.as shown, the peripheral portion101bis adjacent to the vibrating portion101ain a direction parallel to the XZ′-plane. It is noted that the lamination order of the laminated structure101is not particularly limited, and the temperature detection unit20may be provided on a base member30side of the quartz crystal resonator10.

When the laminated structure is viewed from the viewpoint of portions of the respective layers overlapping each other in the laminated structure101, for example, the entirety of the temperature detection unit20faces only part of the quartz crystal resonator10in the Y′-axis direction. To be specific, when the laminated structure101is viewed in a plan view in the +Y′-axis direction, the quartz crystal resonator10and the temperature detection unit20do not overlap each other in the vibrating portion101aand overlap each other in the peripheral portion101b.In addition, an outer edge portion of the temperature detection unit20overlaps an outer edge portion of the quartz crystal resonator10, except for a through hole29to be described later. However, the laminated structure101is not limited to the above described configuration. For example, the entirety of the quartz crystal resonator10may face only part of the temperature detection unit20in the Y′-axis direction. That is, when viewed in the plan view in the +Y′-axis direction, the quartz crystal resonator10may be located inside the temperature detection unit20. In addition, the entirety of the quartz crystal resonator10and the entirety of the temperature detection unit20may face each other in the Y′-axis direction, or part of the quartz crystal resonator10and part of the temperature detection unit20may face each other in the Y′-axis direction.

First, the quartz crystal resonator10will be described.

The quartz crystal resonator10is an element that vibrates a quartz crystal by a piezoelectric effect and converts electrical energy into mechanical energy. As illustrated inFIG.2, the quartz crystal resonator10includes a quartz crystal element11which is thin, a first excitation electrode14aand a second excitation electrode14bforming a pair of excitation electrodes, a first extended electrode15aand a second extended electrode15bforming a pair of extended electrodes, and a first connection electrode16aand a second connection electrode16bforming a pair of connection electrodes. The quartz crystal resonator10further includes a third connection electrode16cand a fourth connection electrode16dforming a pair of connection electrodes. When viewed in a plan view in the +Y′-axis direction, the shape of the quartz crystal resonator10is, for example, a rectangular shape. However, the shape of the quartz crystal resonator10is not limited to the above and may be a circular shape, an elliptical shape, a polygonal shape, or a combination thereof in alternative aspects.

The quartz crystal element11has an upper surface11A and a lower surface11B opposed to each other. The upper surface11A is located on a side opposite to a side facing the base member30, that is, on the side facing a top surface portion41of the cover member40to be described later. The lower surface11B is located on the side facing the base member30. The quartz crystal element11corresponds to a piezoelectric layer, and the upper surface11A and the lower surface11B correspond to a pair of principal surfaces of the piezoelectric layer.

The quartz crystal element11is, for example, an AT-cut quartz crystal element. The AT-cut quartz crystal element11is formed such that, in an orthogonal coordinate system including the X-axis, the Y′-axis, and the Z′-axis intersecting with each other, a surface parallel to the plane specified by the X-axis and the Z′-axis (hereinafter referred to as an “XZ′ surface”; the same applies to surfaces specified by other axes) is a principal surface and a direction parallel to the Y′-axis is a thickness. For example, the AT-cut quartz crystal element11is formed by etching a quartz crystal substrate (for example, a quartz crystal wafer) obtained by cutting and polishing a crystal substance of synthetic quartz crystal. The processing method of the quartz crystal substrate is not limited to etching and may be processing using a dicer, a water jet, a laser, or the like.

The quartz crystal resonator10using the AT-cut quartz crystal element11has high frequency stability in a wide temperature range. In the AT-cut quartz crystal resonator10, a thickness shear vibration mode is used as main vibration in operation. The rotation angles of the Y′-axis and the Z′-axis in the AT-cut quartz crystal element11may be inclined in a range of not less than −5 degrees and not more than 15 degrees from 35 degrees and 15 minutes. As the cut-angles of the quartz crystal element11, a different cut other than the AT-cut may be applied. For example, a BT-cut, a GT-cut, an SC-cut, or the like may be applied. The quartz crystal resonator may be a tuning-fork type quartz crystal resonator using a quartz crystal element having a cut-angle referred to as a Z plate.

Moreover, the AT-cut quartz crystal element11has a plate shape having a long-side direction in which long sides parallel to the X-axis direction extend, a short-side direction in which short sides parallel to the Z′-axis direction extend, and a thickness direction in which a thickness parallel to the Y′-axis direction extends. The quartz crystal element11has a rectangular shape when the upper surface11A is viewed in a plan view and has a flat-plate shape with a uniform thickness.

It is noted that the planar shape of the quartz crystal element11when the upper surface11A is viewed in the plan view is not limited to a rectangular shape. The planar shape of the quartz crystal element11may be a polygonal shape, a circular shape, an elliptical shape, or a combination thereof. In addition, the planar shape of the quartz crystal element11may be a tuning-fork shape having a base portion and vibrating arm portions extending in parallel from the base portion. A slit may be formed in the quartz crystal element11for the purpose of suppressing vibration leakage or stress transmission.

The shape of the quartz crystal element11is not limited to a flat-plate shape having a uniform thickness. For the purpose of suppressing vibration leakage or stress transmission, the quartz crystal element11in the vibrating portion101amay be thicker or thinner than the quartz crystal element11in the peripheral portion101b.In other words, the quartz crystal element11may have a mesa structure or an inverted mesa structure. In this case, the boundary between the vibrating portion101aand the peripheral portion101bof the quartz crystal element11may form, for example, a tapered shape in which the thickness of the quartz crystal element11is continuously changed or may form a stepwise shape in which the thickness is discontinuously changed. The quartz crystal element11may have a convex structure or a beveled structure in which the amount of change in the thicknesses at the boundary between the vibrating portion101aand the peripheral portion101bchanges continuously. The mesa structure or the inverted mesa structure may be provided on only one of the upper surface11A and the lower surface11B of the quartz crystal element11or may be provided on both the surfaces thereof.

As further shown, the first excitation electrode14aand the second excitation electrode14bare provided in the vibrating portion101a.The first excitation electrode14ais provided on an upper surface11A side of the quartz crystal element11, and the second excitation electrode14bis provided on a lower surface11B side of the quartz crystal element11. In other words, the first excitation electrode14ais provided on a cover member40side of the principal surface of the quartz crystal element11, and the second excitation electrode14bis provided on a base member30side of the principal surface of the quartz crystal element11. The first excitation electrode14aand the second excitation electrode14bface each other with the quartz crystal element11therebetween. When the upper surface11A of the quartz crystal element11is viewed in the plan view, the first excitation electrode14aand the second excitation electrode14beach have a rectangular shape and are arranged so as to overlap each other substantially entirely. Each of the first excitation electrode14aand the second excitation electrode14bhas a long side parallel to the X-axis direction, a short side parallel to the Z′-axis direction, and a thickness parallel to the Y′-axis direction. When the laminated structure101is viewed in the plan view in the +Y′-axis direction, the first excitation electrode14aand the second excitation electrode14bare provided inside the through hole29formed in the semiconductor layer21to be described later.

It is noted that the planar shape of the first excitation electrode14aand the second excitation electrode14bwhen the upper surface11A of the quartz crystal element11is viewed in the plan view is not limited to a rectangular shape. The planar shape of the first excitation electrode14aand the second excitation electrode14bmay be a polygonal shape, a circular shape, an elliptical shape, or a combination thereof.

The first extended electrode15ais provided on the upper surface11A side of the quartz crystal element11, and the second extended electrode15bis provided on the lower surface11B side of the quartz crystal element11. The first extended electrode15aelectrically connects the first excitation electrode14aand the first connection electrode16a.The second extended electrode15belectrically connects the second excitation electrode14band the second connection electrode16b.To be specific, as illustrated inFIGS.2and3, the first extended electrode15aextends along the X-axis direction, one end of the first extended electrode15ais connected to the first excitation electrode14ain the vibrating portion101a,and the other end is connected to a through electrode connected to the first connection electrode16ain the peripheral portion101b.The second extended electrode15bextends along the X-axis direction, one end of the second extended electrode15bis connected to the second excitation electrode14bin the vibrating portion101a,and the other end is electrically connected to the second connection electrode16bin the peripheral portion101b.From the viewpoint of reducing stray capacitance, the first extended electrode15aand the second extended electrode15bare separated from each other when the upper surface11A of the quartz crystal element11is viewed in the plan view, and the first extended electrode15ais provided in the +Z′-axis direction with respect to the second extended electrode15b.

Note that a method for electrical connection between the first extended electrode15aand the first connection electrode16ais not limited to connection using the through electrode penetrating the quartz crystal element11along the Y′-axis direction. The first extended electrode15aand the first connection electrode16amay be connected to each other using, for example, a side surface electrode provided on a side surface connecting the upper surface11A and the lower surface11B of the quartz crystal element11in an alternative aspect.

Moreover, the first connection electrode16aand the second connection electrode16bare electrodes for electrically connecting the first excitation electrode14aand the second excitation electrode14bto the base member30, respectively, and are provided on the lower surface11B side of the quartz crystal element11in the peripheral portion101b.As illustrated inFIG.2, the first connection electrode16aand the second connection electrode16bare provided at an end portion on the −X-axis direction side with respect to the first excitation electrode14aand the second excitation electrode14b,and the first connection electrode16ais provided in the +Z′-axis direction with respect to the second connection electrode16b.

The third connection electrode16cand the fourth connection electrode16dare electrodes for electrically connecting a first measurement electrode24cand a second measurement electrode24d,which will be described later, to the base member30, respectively, and are provided on the lower surface11B side of the quartz crystal element11in the peripheral portion101b.In the example illustrated inFIG.2, the third connection electrode16cand the fourth connection electrode16dare provided at corner portions on the −X-axis direction side with respect to the first excitation electrode14aand the second excitation electrode14b,respectively. The fourth connection electrode16dis provided in the +Z′-axis direction with respect to the first connection electrode16a,and the third connection electrode16cis provided in the −Z′-axis direction with respect to the second connection electrode16b.

The first excitation electrode14aand the second excitation electrode14b,the first extended electrode15aand the second extended electrode15b,and the first connection electrode16ato the fourth connection electrode16dare provided by laminating, for example, chromium (Cr) and gold (Au) in this order. It is noted that chromium is superior to gold in adhesion to the quartz crystal element11, and gold is superior to chromium in chemical stability. For this reason, in a case where the electrodes of the quartz crystal resonator10have a multilayer structure formed of chromium and gold, peeling and oxidation of the electrodes can be suppressed, and the quartz crystal resonator10with high reliability can be provided. It is also noted that the material forming the electrode of the quartz crystal resonator10is not limited to Cr and Au, and the electrode may contain a metal material, such as Ti, Mo, Al, Ni, Pd, Ag, or Cu. The electrode may contain conductive ceramics, a conductive resin, or the like.

Next, the temperature detection unit20will be described.

The temperature detection unit20includes a semiconductor layer21laminated on the quartz crystal resonator10, and the first measurement electrode24cand the second measurement electrode24dforming a pair of measurement electrodes. The temperature detection unit20is provided in the peripheral portion101bso as to avoid the vibrating portion101aand has a frame shape continuous in the circumferential direction so as to surround the vibrating portion101a.When viewed in the plan view in the +Y′-axis direction, the shape of the outer edge portion of the temperature detection unit20is, for example, a rectangular shape, and is substantially the same as (i.e., congruent with) the shape of the quartz crystal resonator10. However, the shape of the outer edge portion of the temperature detection unit20is not limited to a rectangular shape and may be a circular shape, an elliptical shape, a polygonal shape, or a combination thereof. In addition, the shape of the outer edge portion of the temperature detection unit20is not limited to a shape congruent with the shape of the quartz crystal resonator10and may be a shape similar to the shape of the quartz crystal resonator10or may be different from the shape of the quartz crystal resonator10.

According to the exemplary aspect, the semiconductor layer21is configured to provide a conductive path between the first measurement electrode24cand the second measurement electrode24dand to function as a resistance element whose resistance value changes according to the temperature. Since the semiconductor layer21is laminated on the quartz crystal resonator10, the semiconductor layer21and the quartz crystal resonator10are in a thermal equilibrium state. Therefore, the first measurement electrode24cand the second measurement electrode24dmeasure the resistance value of the semiconductor layer21that changes based on the temperature of the quartz crystal resonator10.

The first measurement electrode24cand the second measurement electrode24dare not limited to those described above as long as signals based on the temperature of the quartz crystal resonator10can be measured through the semiconductor layer21. In alternative aspects, the first measurement electrode24cand the second measurement electrode24dcan be configured to measure inductance or capacitance, for example.

The semiconductor layer21includes an upper surface21A and a lower surface21B opposed to each other. The upper surface21A is located on a side facing the top surface portion41of the cover member40to be described later. The lower surface21B is located on a side facing the base member30, that is, the side facing the quartz crystal resonator10. The upper surface21A and the lower surface21B correspond to a pair of principal surfaces of the semiconductor layer21.

When the upper surface21A of the semiconductor layer21is viewed in the plan view, the semiconductor layer21includes a front end portion22a,a rear end portion22b,a right end portion22c,and a left end portion22d.The front end portion22aand the rear end portion22bcorrespond to a pair of short sides facing each other in the X-axis direction and extending along the Z′-axis direction. The right end portion22cand the left end portion22dcorrespond to a pair of long sides facing each other in the Z′-axis direction and extending along the X-axis direction. That is, both ends of the front end portion22aare connected to respective one ends of the right end portion22cand the left end portion22d,and both ends of the rear end portion22bare connected to the respective other ends of the right end portion22cand the left end portion22d.The front end portion22ais located on the side of the first connection electrode16aand the second connection electrode16bwith respect to the first excitation electrode14aand the second excitation electrode14b.The rear end portion22bis located on the +X-axis direction side with respect to the front end portion22a,and the left end portion22dis located on the +Z′-axis direction side with respect to the right end portion22c.

As further shown, a through hole29is formed in the semiconductor layer21so as to open to both the upper surface21A and the lower surface21B. The through hole29is formed in the vibrating portion101a.The semiconductor layer21is provided so as to avoid the vibrating portion101aand to not be in contact with the first excitation electrode14aand the second excitation electrode14b.The semiconductor layer21is provided so as to be in contact with the quartz crystal resonator10over the substantially entirety of peripheral portion101band has a rectangular frame shape along the front end portion22a,the rear end portion22b,the right end portion22c,and the left end portion22d.

The semiconductor layer21includes a semiconductor having low electrical conductivity so that the first excitation electrode14ais sufficiently insulated/isolated from the first measurement electrode24cand the second measurement electrode24d.For example, the semiconductor layer21is an i-type or a nondegenerate low-concentration n-type or p-type silicon semiconductor. However, the semiconductor layer21is not limited to the above and may be a single element semiconductor such as germanium, a compound semiconductor such as gallium arsenide, or an organic semiconductor such as pentacene.

In the exemplary aspect, the first measurement electrode24cand the second measurement electrode24dare provided on the lower surface21B of the semiconductor layer21and are sandwiched between the quartz crystal element11and the semiconductor layer21. The first measurement electrode24cand the second measurement electrode24dare provided at an end portion on the same side as the first connection electrode16aand the second connection electrode16bwith respect to the first excitation electrode14aand the second excitation electrode14b.In addition, the first measurement electrode24cand the second measurement electrode24dare farther away from the first excitation electrode14aand the second excitation electrode14bthan the first connection electrode16aand the second connection electrode16bare. The laminated structure101has a so-called cantilever structure in which a side of one end portion (e.g., a portion corresponding to the front end portion22aof the semiconductor layer21) of the end portions on the +X-axis direction side and the −X-axis direction side with respect to the first excitation electrode14aand the second excitation electrode14bis bonded to the base member30and a side of the other end portion (e.g., a portion corresponding to the rear end portion22bof the semiconductor layer21) is separated from the base member30. The first measurement electrode24cis provided at a corner formed by the front end portion22aand the right end portion22c,and the second measurement electrode24dis provided at a corner formed by the front end portion22aand the left end portion22d.The first measurement electrode24cand the second measurement electrode24dare electrically connected to the third connection electrode16cand the fourth connection electrode16d,respectively, by side surface electrodes provided on the side surfaces of the quartz crystal element11.

It is noted that the first measurement electrode24cand the second measurement electrode24dcan be provided on the upper surface21A of the semiconductor layer21or can be provided on a side surface connecting the upper surface21A and the lower surface21B of the semiconductor layer21. When the upper surface21A of the semiconductor layer21is viewed in the plan view, the first measurement electrode24cand the second measurement electrode24dmay be provided on the side opposite to the first connection electrode16aand the second connection electrode16bwith respect to the first excitation electrode14aand the second excitation electrode14b.That is, the laminated structure101may have a so-called double-supported structure in which the both sides of the one end portion and the other end portion described above with respect to the first excitation electrode14aand the second excitation electrode14bare bonded to the base member30. In addition, the first measurement electrode24cand the second measurement electrode24dmay be electrically connected to the third connection electrode16cand the fourth connection electrode16d,respectively, by a through electrode.

Next, the base member30will be described.

In the exemplary aspect, the base member30holds the quartz crystal resonator10such that the quartz crystal resonator10can be excited. The base member30includes a base body31having an upper surface31A and a lower surface31B facing each other. The upper surface31A is located on a side of the laminated structure101and the cover member40and corresponds to a mounting surface on which the laminated structure101is mounted. The lower surface31B corresponds to, for example, a mounting surface bonded to an external circuit board (not illustrated). The base body31is formed of a sintered material such as insulating ceramics (alumina), for example. From the viewpoint of suppressing generation of thermal stress, the base body31is preferably formed of a heat resistant material. From the viewpoint of suppressing the stress applied to the quartz crystal resonator10due to thermal history, the base body31may be formed of a material having a thermal expansion coefficient close to that of the quartz crystal element11and, for example, may be formed of quartz crystal.

As further shown inFIG.1, the base member30includes a first electrode pad33aand a second electrode pad33bforming a pair of electrode pads, and a third electrode pad33cand a fourth electrode pad33dforming a pair of electrode pads. The first electrode pad33ato the fourth electrode pad33dare provided on the upper surface31A of the base body31. The first electrode pad33aand the second electrode pad33bare terminals for electrically connecting the quartz crystal resonator10to the base member30, and the third electrode pad33cand the fourth electrode pad33dare terminals for electrically connecting the temperature detection unit20to the base member30. The first electrode pad33ato the fourth electrode pad33dare arranged along the Z′-axis direction at an end portion on the −X-axis direction side of the base member30.

The base member30includes a first outer electrode35a,a second outer electrode35b,a third outer electrode35c,and a fourth outer electrode35d.The first outer electrode35ato the fourth outer electrode35dare provided on the lower surface31B of the base body31. The first outer electrode35aand the second outer electrode35bare terminals for electrically connecting an external circuit board (not illustrated) and the quartz crystal resonator unit100. The third outer electrode35cand the fourth outer electrode35dare terminals for electrically connecting an external circuit board (not illustrated) and the temperature detection unit20.

Moreover, the first outer electrode35aand the second outer electrode35bare arranged along the Z′-axis direction at an end portion on the +X-axis direction side of the base member30. The third outer electrode35cand the fourth outer electrode35dare arranged along the Z′-axis direction at an end portion on the −X-axis direction side of the base member30. The first electrode pad33ais electrically connected to the first outer electrode35avia a first through electrode34apenetrating the base body31and base wiring provided on the lower surface31B of the base body31. The second electrode pad33bis electrically connected to the second outer electrode35bvia a second through electrode34bpenetrating the base body31along the Y′-axis direction and base wiring provided on the lower surface31B of the base body31. The third electrode pad33cand the fourth electrode pad33dare electrically connected to the third outer electrode35cand the fourth outer electrode35dvia a third through electrode34cand a fourth through electrode34dpenetrating the base body31, respectively.

The first electrode pad33aand the second electrode pad33bcan be electrically connected to the first outer electrode35aand the second outer electrode35b,respectively, via base wiring provided on the upper surface31A of the base body31. The first electrode pad33ato the fourth electrode pad33dcan be electrically connected to the first outer electrode35ato the fourth outer electrode35d,respectively, via a side surface electrode provided on a side surface connecting the upper surface31A and the lower surface31B of the base body31. The first outer electrode35ato the fourth outer electrode35dmay be a castellation electrode provided in a concave shape on a side surface of the base body31.

The base member30includes a first conductive holding member36aand a second conductive holding member36bthat form a pair of conductive holding members, and a third conductive holding member36cand a fourth conductive holding member36dthat form a pair of conductive holding members. The first conductive holding member36ato the fourth conductive holding member36dof the base member30mount the laminated structure101and electrically connect the laminated structure101and the base member30. The first conductive holding member36abonds and electrically connects the first electrode pad33aand the first connection electrode16a.The second conductive holding member36bbonds and electrically connects the second electrode pad33band the second connection electrode16b.The third conductive holding member36cbonds and electrically connects the third electrode pad33cand the third connection electrode16c.The fourth conductive holding member36dbonds and electrically connects the fourth electrode pad33dand the fourth connection electrode16d.The first conductive holding member36ato the fourth conductive holding member36dhold the laminated structure101spaced from the base member30so that the vibrating portion101acan be excited.

The first conductive holding member36ato the fourth conductive holding member36dare, for example, conductive adhesives including thermosetting resins, ultraviolet curing resins, and the like, having silicone-based resins as a base material and include additives such as conductive particles for imparting conductivity to the adhesives. As the conductive particles, for example, conductive particles containing silver (Ag) are used. The base material of the conductive adhesive may be an epoxy resin, an acrylic resin, or the like. The first conductive holding member36ato the fourth conductive holding member36dare provided by applying an uncured conductive adhesive paste which is a precursor and then curing the conductive adhesive paste through chemical reactions caused by heating, ultraviolet irradiation, or the like. Moreover, a filler can be added to the adhesive of the first conductive holding member36ato the fourth conductive holding member36dfor the purpose of increasing the strength or for the purpose of maintaining the distance between the base member30and the quartz crystal resonator10. It is noted that the first conductive holding member36ato the fourth conductive holding member36dmay be formed by solder.

Next, the cover member40will be described.

The cover member40is bonded to the base member30and forms an internal space49in which the laminated structure101is accommodated between the cover member40and the base member30. Although the shape of the cover member40is not particularly limited as long as the cover member40can accommodate at least the vibrating portion101aof the laminated structure101and the material of the cover member40is not particularly limited, the cover member is formed of a conductive material such as metal, for example. Since the cover member40is formed of a conductive material, an electromagnetic shielding function that reduces entering and leaving of electromagnetic waves to and from the internal space49is imparted to the cover member40.

The cover member40includes the top surface portion41having a flat-plate shape and a side wall portion42connected to an outer edge of the top surface portion41and extending in a direction intersecting a principal surface of the top surface portion41. The planar shape of the top surface portion41when viewed in the plan view in the direction normal to the principal surface is, for example, a rectangular shape. The tip end of the side wall portion42extends in a frame shape so as to surround the periphery of the laminated structure101.

Moreover, the cover member40can be bonded to an outer edge portion of the laminated structure101to form the internal space49. At this time, the outer edge portion of the laminated structure101can be sandwiched between the base member30and the cover member40. Further, the cover member40may be formed of a ceramic material, a semiconductor material, a resin material, or the like, for example. In addition, the planar shape of the top surface portion41may be a polygonal shape, a circular shape, an elliptical shape, or a combination thereof.

Next, the bonding member50will be described.

The bonding member50is provided over the entire circumference of each of the base member30and the cover member40and has a rectangular frame shape. In addition, the first electrode pad33ato the fourth electrode pad33dare arranged inside the bonding member50, and the bonding member50is provided so as to surround the laminated structure101. The bonding member50bonds the tip end of the side wall portion22of the cover member40and the upper surface31A of the base body31of the base member30. Moreover, the bonding member50is formed of, for example, a metallized layer provided on the upper surface31A of the base body31and an Au—Sn alloy-based metallic solder provided on the metallized layer.

It is also noted that the bonding member50is not limited to a frame shape that is continuous in the circumferential direction and may be provided discontinuously in the circumferential direction in an alternative aspect. Further, the bonding member50may be formed of a resin-based or glass-based insulating adhesive or the like.

Next, an operation of the quartz crystal resonator unit100will be described.

The quartz crystal resonator unit100has a temperature detection mode for measuring the temperature of the quartz crystal resonator10and a signal output mode for driving the quartz crystal resonator10by performing temperature compensation based on the measurement result in the temperature detection mode.

In the temperature detection mode, for example, by applying a current to the semiconductor layer21between the first measurement electrode24cand the second measurement electrode24d,and the resistance value of the semiconductor layer21is measured. Although the resistance value of the semiconductor layer21changes depending on the temperature of the semiconductor layer21, the temperature of the semiconductor layer21becomes substantially the same as the temperature of the quartz crystal resonator10due to thermal conduction between the semiconductor layer21and the quartz crystal resonator10. Therefore, in the temperature detection mode, the temperature of the quartz crystal resonator10is measured by measuring a change of the resistance value of the semiconductor layer21.

In the signal output mode, a frequency of an oscillation circuit based on the quartz crystal resonator10is corrected by temperature compensation based on the measurement result in the temperature detection mode. The temperature compensation is achieved, for example, by changing a signal to a variable capacitor for correcting the frequency.

As described above, the quartz crystal resonator unit100according to the present embodiment includes the quartz crystal resonator10and the temperature detection unit20laminated on the quartz crystal resonator10. The temperature detection unit20includes the semiconductor layer21laminated on the quartz crystal resonator10and the first measurement electrode24cand the second measurement electrode24dforming a pair of measurement electrodes for measuring a resistance value based on the temperature of the quartz crystal resonator10through the semiconductor layer21.

According to this configuration, a heat transfer area between a semiconductor layer and a quartz crystal resonator is increased compared to the configuration in which a semiconductor layer whose resistance value changes with temperature and is measured and a quartz crystal resonator are connected with a conductive holding member therebetween. Therefore, the rate of heat transfer from the quartz crystal resonator to the semiconductor layer is improved, and the temperature difference between the semiconductor layer and the quartz crystal resonator is reduced. Therefore, the temperature of the quartz crystal resonator can be more accurately measured. Accordingly, a quartz crystal resonator unit is provided that is configured to output a frequency clock with narrow tolerance accuracy.

What is measured by a pair of measurement electrodes is a signal measured through the semiconductor layer and is not limited to a resistance value as long as a signal changes based on the temperature of the quartz crystal resonator. The pair of measurement electrodes may measure, for example, inductance or capacitance, as described above.

Further, in the quartz crystal resonator unit100according to the present embodiment, the semiconductor layer21is provided so as to not be in contact with the first excitation electrode14aand the second excitation electrode14bconstituting the pair of excitation electrodes.

According to this configuration, inhibition of the vibration of the quartz crystal resonator by the semiconductor layer is reduced, and deterioration of vibration characteristics of the quartz crystal resonator is suppressed.

In addition, the first measurement electrode24cand the second measurement electrode24dare located farther away from the first excitation electrode14aand the second excitation electrode14bthan the first connection electrode16aand the second connection electrode16bare. According to this configuration, parasitic capacitance can be reduced between a pair of connection electrodes connecting a pair of excitation electrodes and the pair of measurement electrodes, and parasitic capacitance can be reduced between the pair of extended electrodes and the pair of measurement electrodes.

Hereinafter, configurations of a quartz crystal resonator unit according to additional exemplary embodiments of the present invention will be described. Note that, in the following embodiments, description of matters common to the first embodiment described above will be omitted, and only different points will be described. In particular, similar operation and effects by a similar configuration will not be described one by one.

Second Exemplary Embodiment

A laminated structure201according to a second embodiment will be described with reference toFIG.4.FIG.4is a sectional view schematically illustrating a configuration of a laminated structure according to the second embodiment.

The laminated structure201according to the second embodiment is different from the laminated structure101according to the first embodiment in that a bottomed recess229is formed in a semiconductor layer221instead of the through hole. The recess229has a cavity on a lower surface221B side of a semiconductor layer221and has a bottom on an upper surface221A side. That is, the semiconductor layer220is provided so as to be in non-contact with the first excitation electrode14aand the second excitation electrode14bforming the pair of excitation electrodes.

Also in this embodiment, inhibition of the vibration of a quartz crystal resonator by a semiconductor layer is reduced, and deterioration of vibration characteristics of the quartz crystal resonator is suppressed.

Third Exemplary Embodiment

A laminated structure301according to a third embodiment will be described with reference toFIG.5.FIG.5is a sectional view schematically illustrating a configuration of a laminated structure according to the third embodiment.

The laminated structure301according to the third embodiment is different from the laminated structure101according to the first embodiment in that an insulator layer328is provided between the quartz crystal resonator10and the semiconductor layer21. The second measurement electrode24dis provided between the insulator layer328and the semiconductor layer21, and the first extended electrode15ais provided between the quartz crystal element11and the insulator layer328. That is, the insulation/isolation between the first extended electrode15aand the second measurement electrode24dis improved by the insulator layer328. Although not illustrated in the drawings, the insulation/isolation between the first extended electrode15aand the first measurement electrode24cis similarly improved.

According to this configuration, signal leakage from an excitation electrode to a measurement electrode is suppressed, and deterioration of vibration characteristics of a quartz crystal resonator is suppressed.

Fourth Exemplary Embodiment

A laminated structure401according to a fourth embodiment will be described with reference toFIG.6.FIG.6is a plan view schematically illustrating a configuration of a laminated structure according to the fourth embodiment. InFIG.6, for the purpose of making it easy to distinguish the quartz crystal resonator and the temperature detection unit, the temperature detection unit is depicted inside the quartz crystal resonator, but this illustration is not intended to indicate that the external dimensions of the quartz crystal resonator and the temperature detection unit are different from each other. Similarly to the first embodiment, it is assumed that when viewed in the plan view in the +Y′-axis direction, an outer edge portion of the temperature detection unit overlaps an outer edge portion of the quartz crystal resonator in the case where a slit SLA to be described below and the through hole29described above are ignored. The same applies to the depiction of the quartz crystal resonator and the temperature detection unit inFIGS.7to9.

The laminated structure401according to the fourth embodiment is different from the laminated structure101according to the first embodiment in that the slit SLA is formed in the semiconductor layer21.

The slit SLA is open on both side surfaces on a through hole29side and the outer side of a front end portion22a,and exposes the upper surface11A of the quartz crystal element11. The slit SLA makes the semiconductor layer21, which has a frame shape, discontinuous in the circumferential direction when the upper surface21A of the semiconductor layer21is viewed in the plan view. To be specific, when the upper surface21A of the semiconductor layer21is viewed in the plan view, the slit SLA is provided between the first extended electrode15aand the second extended electrode15b,between the first connection electrode16aand the second connection electrode16b,between the first measurement electrode24cand the second measurement electrode24d,and between the third connection electrode16cand the fourth connection electrode16d.In other words, the semiconductor layer21is discontinuous in the shortest distance connecting the first measurement electrode24cand the second measurement electrode24dconstituting the pair of measurement electrodes.

Accordingly, a conductive path of a semiconductor layer functioning as a resistance element is formed so as to go around a first excitation electrode and a second excitation electrode along a right end portion, a rear end portion, and a left end portion. Compared to the configuration that a semiconductor layer is continuous in the shortest distance connecting between a pair of measurement electrodes, the path length of the semiconductor layer as a resistance element is increased according to the present embodiment, and thus the measurement accuracy of the change in the resistance value of the semiconductor layer is improved. Therefore, the accuracy of temperature measurement of a quartz crystal resonator is improved.

Fifth Exemplary Embodiment

A laminated structure501according to a fifth embodiment will be described with reference toFIG.7. FIG.7is a plan view schematically illustrating a configuration of a laminated structure according to the fifth embodiment.

The laminated structure501according to the fifth embodiment is different from the laminated structure401according to the fourth embodiment in that a plurality of slits SLB is formed in the semiconductor layer21.

When the upper surface21A of the semiconductor layer21is viewed in the plan view, the plurality of slits SLB exposes the upper surface11A of the quartz crystal element11. In addition, the plurality of slits SLB is open to one side surface of the through hole29side or the outer side of the left end portion22don the left end portion22dside with respect to the through hole29. Similarly, the plurality of slits SLB is open to one side surface of the through hole29side or the outer side of the rear end portion22bon the rear end portion22bside with respect to the through hole29, and open to one side surface of the through hole29side or the outer side of the right end portion22con the right end portion22cside with respect to the through hole29.

Accordingly, since the path length of a semiconductor layer as a resistance element is increased, the measurement accuracy of the change in a resistance value of the semiconductor layer is improved. Therefore, the accuracy of temperature measurement of a quartz crystal resonator is improved.

Sixth Exemplary Embodiment

A laminated structure601according to a sixth embodiment will be described with reference toFIG.8.FIG.8is a plan view schematically illustrating a configuration of a laminated structure according to the sixth embodiment.

The laminated structure601according to the sixth embodiment is different from the laminated structure501according to the fifth embodiment in that a plurality of slits SLB is formed along the X-axis direction.

When the upper surface21A of the semiconductor layer21is viewed in the plan view, the plurality of slits SLB is open to one side surface of the outer side of the front end portion22aor the rear end portion22bon the left end portion22dside with respect to the through hole29. In addition, the plurality of slits SLB is open to one side surface of the outer side of the front end portion22aor the rear end portion22bon the right end portion22cside with respect to the through hole29. On the rear end portion22bside with respect to the through hole29, the plurality of slits SLB has the same configuration as in the fifth embodiment.

Also in the present embodiment, the same effects as those of the fifth embodiment can be obtained. As long as the path length of a semiconductor layer as a resistance element is increased, the shapes of the plurality of slits are not limited to those in the fifth embodiment and the sixth embodiment. For example, each of the plurality of slits may be formed along the Z′-axis direction, or at least part of the plurality of slits may be bent.

Seventh Exemplary Embodiment

A laminated structure701according to a seventh embodiment will be described with reference toFIG.9.FIG.9is a plan view schematically illustrating a configuration of a laminated structure according to the seventh embodiment.

The laminated structure701according to the seventh embodiment is different from the laminated structure401according to the fourth embodiment in that the semiconductor layer21is formed in a U-shape.

When the upper surface21A of the semiconductor layer21is viewed in the plan view, the semiconductor layer21is provided along the right end portion22c,the rear end portion22b,and the left end portion22d.In addition, the semiconductor layer21is provided at outer side portions of an electrode group of the quartz crystal resonator10so as to avoid the electrode group of the first excitation electrode14aand the second excitation electrode14b,the first extended electrode15aand the second extended electrode15b,and the first connection electrode16aand the second connection electrode16b.Therefore, the insulation/isolation between the first extended electrode15aand the first measurement electrode24cand the insulation/isolation between the first extended electrode15aand the second measurement electrode24dare improved.

Accordingly, the path length of a semiconductor layer as a resistance element is increased, and signal leakage from an excitation electrode to a measurement electrode is suppressed. Therefore, the accuracy of temperature measurement of a quartz crystal resonator is improved, and deterioration of vibration characteristics of the quartz crystal resonator is suppressed.

Eighth Exemplary Embodiment

A quartz crystal resonator810according to an eighth embodiment will be described with reference toFIG.10.FIG.10is a perspective view schematically illustrating a configuration of a quartz crystal resonator according to the eighth embodiment.

The quartz crystal resonator810according to the eighth embodiment is different from the quartz crystal resonator10according to the first embodiment in that the second connection electrode is omitted and the second extended electrode15belectrically connects the second excitation electrode14band the third connection electrode16c.

The first measurement electrode24cis electrically connected to the second excitation electrode14b.Although not illustrated, the laminated structure according to the eighth embodiment is mounted on the base member with the first conductive holding member36a,the third conductive holding member36c,and the fourth conductive holding member36d.The third connection electrode16cserves as an input terminal for driving vibration to the second excitation electrode14band also serves as an input terminal for a measurement signal to the first measurement electrode24c.In other words, in the temperature detection mode, the measurement signal based on the temperature of the quartz crystal resonator810are measured through the third connection electrode16cand the fourth connection electrode16dthrough the semiconductor layer21. In addition, in the signal output mode, a drive signal for driving the quartz crystal resonator10is input to the third connection electrode16cand the fourth connection electrode16d,and the frequency of the oscillation circuit based on the quartz crystal resonator10is corrected by temperature compensation based on measurement results in the temperature detection mode.

Ninth Exemplary Embodiment

A quartz crystal resonator910according to a ninth embodiment will be described with reference toFIG.11.FIG.11is a perspective view schematically illustrating a configuration of a quartz crystal resonator according to the ninth embodiment.

The quartz crystal resonator910according to the ninth embodiment is different from the quartz crystal resonator10according to the first embodiment in that the first connection electrode is omitted and the first extended electrode15aelectrically connects the first excitation electrode14aand the fourth connection electrode16d.

The second measurement electrode24dis electrically connected to the first excitation electrode14a.Although not illustrated, the laminated structure according to the ninth embodiment is mounted on the base member with the second conductive holding member36b,the third conductive holding member36c,and the fourth conductive holding member36d.The fourth connection electrode16dserves as an input terminal for driving vibration to the first excitation electrode14aand also serves as an input terminal for the measurement signal to the second measurement electrode24d.

Tenth Exemplary Embodiment

A quartz crystal resonator A10according to a tenth embodiment will be described with reference toFIG.12.FIG.12is a perspective view schematically illustrating a configuration of a quartz crystal resonator according to the tenth embodiment.

The quartz crystal resonator A10according to the tenth embodiment is different from the quartz crystal resonator10according to the first embodiment in that the first connection electrode and the second connection electrode are omitted, the second extended electrode15belectrically connects the second excitation electrode14band the third connection electrode16c,and the first extended electrode15aelectrically connects the first excitation electrode14aand the fourth connection electrode16d.

As illustrated in the eighth to tenth embodiments, at least one of the pair of measurement electrodes may be electrically connected to one of the pair of excitation electrodes.

Eleventh Exemplary Embodiment

A laminated structure B01according to an eleventh embodiment will be described with reference toFIG.13.FIG.13is an exploded perspective view schematically illustrating a configuration of a laminated structure according to the eleventh embodiment.

As shown, the laminated structure B01according to the eleventh embodiment is different from the laminated structure101according to the first embodiment in that a temperature detection unit B20is laminated on the base member side of a quartz crystal resonator B10.

The quartz crystal resonator B10and the temperature detection unit B20are laminated such that the lower surface11B of the quartz crystal element11and the upper surface21A of the semiconductor layer21face each other. The first extended electrode15aand the second extended are electrically connected to a first connection electrode16aand a second connection electrode16bprovided on the lower surface21B of the semiconductor layer21via a through electrode penetrating the semiconductor layer21from the upper surface21A to the lower surface21B, respectively. The first measurement electrode24cand the second measurement electrode24dare provided on the lower surface21B of the semiconductor layer21and bonded with the third conductive holding member36cand the fourth conductive holding member36d(not illustrated), respectively.

Twelfth Exemplary Embodiment

A laminated structure C01according to a twelfth embodiment will be described with reference toFIG.14.FIG.14is a sectional view schematically illustrating a configuration of a laminated structure according to the twelfth embodiment.

The laminated structure B01according to the twelfth embodiment is different from the laminated structure101according to the first embodiment in that the semiconductor layer21is in contact with the first excitation electrode14a.

It is desirable that the semiconductor layer21be thinner than the semiconductor layer21according to the first embodiment in order not to inhibit the vibration of the quartz crystal resonator10.

Accordingly, since a heat transfer area between a semiconductor layer and a quartz crystal resonator is increased, the temperature of the quartz crystal resonator can be measured more accurately.

Thirteenth Exemplary Embodiment

An oscillator D99according to a thirteenth embodiment will be described with reference toFIG.15.FIG.15is a sectional view schematically illustrating a configuration of an oscillator according to the thirteenth embodiment.

The oscillator D99further includes a semiconductor integrated circuit60in addition to the quartz crystal resonator unit100. The semiconductor integrated circuit60is formed on the upper surface31A of the base body31. The semiconductor integrated circuit60includes, for example, an oscillation circuit that oscillates the quartz crystal resonator10, a measurement circuit that measures temperature of the semiconductor layer21based on the resistance value of the semiconductor layer21as the temperature of the quartz crystal resonator10, a temperature compensation circuit that corrects the frequency of the oscillation circuit based on the quartz crystal resonator10by temperature compensation based on the measurement result of the measurement circuit, a ROM circuit that stores parameters for temperature compensation, and a voltage generation circuit that provides power necessary for each circuit.

In an exemplary aspect, the semiconductor integrated circuits60may be formed on the lower surface31B of the base body31or may be formed outside the quartz crystal resonator unit100.

In the following description, some or all of the embodiments of the present invention will be added and effects thereof will be described. It is noted that the exemplary embodiments of the present invention are not limited to the following supplementary notes.

According to an aspect of the present invention, there is provided a base member, a cover member and a laminated structure provided between the base member and the cover member. The laminated structure includes a piezoelectric resonator including a piezoelectric layer having a pair of principal surfaces facing each other and a pair of excitation electrodes each provided on corresponding one of the pair of principal surfaces of the piezoelectric layer so as to face each other with the piezoelectric layer therebetween, a semiconductor layer laminated on a side of one of the pair of principal surfaces of the piezoelectric layer of the piezoelectric resonator, and a pair of measurement electrodes provided on the semiconductor layer. The pair of measurement electrodes is configured to measure a signal based on temperature of the piezoelectric resonator through the semiconductor layer.

In one aspect, the pair of measurement electrodes measures a resistance value of the semiconductor layer.

According to this configuration, a heat transfer area can be increased between the semiconductor layer and the quartz crystal resonator compared to the configuration in which the semiconductor layer whose resistance value changes with temperature and is measured and the quartz crystal resonator are connected with the conductive holding member therebetween. Therefore, the rate of heat transfer from the quartz crystal resonator to the semiconductor layer is improved, and the temperature difference between the semiconductor layer and the quartz crystal resonator is reduced. Therefore, the temperature of the quartz crystal resonator can be more accurately measured. Accordingly, a quartz crystal resonator unit can be provided that is constructed for outputting a frequency clock with narrow tolerance accuracy.

In one aspect, the laminated structure further includes an insulator layer provided between the piezoelectric layer and the semiconductor layer.

According to this configuration, signal leakage from the excitation electrode to the measurement electrode is suppressed, and deterioration of vibration characteristics of the quartz crystal resonator is suppressed.

In one aspect, the semiconductor layer is provided so as to not be in contact with the pair of excitation electrodes.

According to this configuration, inhibition of the vibration of the quartz crystal resonator by the semiconductor layer is reduced, and deterioration of vibration characteristics of the quartz crystal resonator is suppressed.

In one aspect, the semiconductor layer is discontinuous in the shortest distance connecting each of the pair of measurement electrodes when the piezoelectric resonator is viewed in the plan view.

According to this configuration, since the path length of the semiconductor layer as the resistance element increases compared to the configuration in which the semiconductor layer is continuous in the shortest distance between the pair of measurement electrodes, the measurement accuracy of the change in the resistance value of the semiconductor layer is improved. Therefore, the accuracy of temperature measurement of the quartz crystal resonator is improved.

In one aspect, a plurality of slits is formed in the semiconductor layer.

In one aspect, the piezoelectric resonator further includes a pair of connection electrodes electrically connected to the pair of excitation electrodes via extended electrodes, and when the pair of principal surfaces of the piezoelectric layer of the piezoelectric resonator is viewed in the plan view, the pair of measurement electrodes is farther away from the pair of excitation electrodes than the pair of connection electrodes.

According to this configuration, parasitic capacitance can be reduced between the pair of connection electrodes connecting the pair of excitation electrodes and the pair of measurement electrodes, and parasitic capacitance can be reduced between the pair of extended electrodes and the pair of measurement electrodes.

In one aspect, at least one of the pair of measurement electrodes is electrically connected to one of the pair of excitation electrodes.

In one aspect, there is provided an oscillator further including a measurement circuit that measures, based on the signal acquired through the semiconductor layer by the pair of measurement electrodes, temperature of the piezoelectric resonator.

In one aspect, a temperature compensation circuit that compensates a frequency of the piezoelectric resonator in response to the measurement circuit is further provided.

As described above, according to one exemplary aspect, a piezoelectric resonator unit is provided in which temperature compensation accuracy is improved and an oscillator including the piezoelectric resonator unit.

It is noted that the embodiments described above are intended to facilitate understanding of the present invention and are not intended to be construed as limiting the present invention. The present invention can be modified/improved without departing from the gist thereof, and the present invention includes equivalents thereof. That is, the embodiments in which design is appropriately changed by those skilled in the art are also included in the scope of the present invention as long as they have the features of the present invention. For example, each element included in each embodiment and the arrangement, material, condition, shape, size, and the like are not limited to those illustrated and can be changed as appropriate. For example, the resonator and the resonator unit of the present invention can be used in timing devices or load sensors. Further, each element included in each embodiment can be combined as long as it is technically possible, and a combination is also included in the scope of the present invention as long as it includes the feature of the present invention.

REFERENCE SIGNS LIST

100QUARTZ CRYSTAL RESONATOR UNIT10QUARTZ CRYSTAL RESONATOR11QUARTZ CRYSTAL ELEMENT11A UPPER SURFACE OF QUARTZ CRYSTAL ELEMENT11B LOWER SURFACE OF QUARTZ CRYSTAL ELEMENT14aFIRST EXCITATION ELECTRODE14bSECOND EXCITATION ELECTRODE15aFIRST EXTENDED ELECTRODE15bSECOND EXTENDED ELECTRODE16aFIRST CONNECTION ELECTRODE16bSECOND CONNECTION ELECTRODE16cTHIRD CONNECTION ELECTRODE16dFOURTH CONNECTION ELECTRODE20TEMPERATURE DETECTION UNIT21SEMICONDUCTOR LAYER21A UPPER SURFACE OF SEMICONDUCTOR LAYER21B LOWER SURFACE OF SEMICONDUCTOR LAYER22aFRONT END PORTION22bREAR END PORTION22cRIGHT END PORTION22dLEFT END PORTION24cFIRST MEASUREMENT ELECTRODE24dSECOND MEASUREMENT ELECTRODE29THROUGH HOLE