Thermistor-equipped quartz crystal device

Abstract

To provide a crystal vibration device with temperature sensor which responds to microminiaturization and ultra-thinning, stably and appropriately detects a temperature fluctuation relating to the crystal vibration device and is improved in electrical characteristics.SOLUTION: A crystal vibration device with thermistor comprises: a package 1; an upper storage part 11A and a lower storage part 11B; a crystal diaphragm 2; a thermistor; and a lid 3. The crystal diaphragm 2 is stored in the upper storage part 11A. The thermistor is stored in the lower storage part 11. The lid 3 seals the upper storage part 11A hermetically. The thermistor includes a veneer thermistor blank as a base material, a pair of operation electrodes 41 and 42 is formed on one surface, and a relay electrode 43 is formed on the other principal surface.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a quartz crystal resonator device with a thermistor, in which a quartz crystal plate and a thermistor are conductively bonded to a package. [Background technology]

[0002] In recent years, as various electronic devices have become more precise, there has been a demand for temperature-compensated crystal oscillation circuits that compensate for frequency fluctuations caused by changes in environmental temperature. To meet this demand, crystal oscillation devices with thermistors, in which a thermistor is attached to a crystal oscillator as a temperature sensor, are widely used.

[0003] By measuring the ambient temperature of the quartz crystal unit using a thermistor and transmitting frequency information and temperature information to an externally mounted temperature compensation circuit, a temperature-compensated frequency signal can be obtained, enabling the operation of electronic devices to be maintained with high precision.

[0004] Such a quartz crystal device with a thermistor is configured such that a quartz crystal plate on which an excitation electrode is formed is housed in a ceramic package, and a thermistor is attached to the outside of the quartz crystal plate to detect the environmental temperature surrounding the quartz crystal unit (see Patent Document 1).

[0005] The above-mentioned thermistor has a laminated structure in which a plurality of thermistor material layers and a plurality of operating electrodes are laminated, and those with a thickness of about 0.3 mm to 0.1 mm are commercially available and in use. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent No. 5900582 Summary of the Invention [Problem to be solved by the invention]

[0007] The above-mentioned thermistor is required to detect temperature changes surrounding the quartz crystal unit with little time lag. However, the thermistors used up until now have a laminated structure, which required a certain thickness (height). This structure sometimes resulted in a difference between the temperature of the quartz crystal unit and the temperature detected by the thermistor as a temperature sensor.

[0008] In such a case, the temperature of the crystal unit cannot be detected accurately, and appropriate temperature compensation cannot be performed in the temperature compensation circuit, so that an accurate frequency signal cannot be provided to the electronic device, which can reduce the operational reliability of the electronic device.

[0009] The present invention has been made in consideration of the above-mentioned problems, and aims to provide a quartz crystal vibration device with a temperature sensor that is capable of responding to ultra-compactness and ultra-thin design, can stably and appropriately detect temperature fluctuations associated with the quartz crystal vibration device, and has excellent electrical characteristics. [Means for solving the problem]

[0010] The quartz crystal resonator device with thermistor according to the present invention is a single plate having an excitation electrode formed on its surface. The device is characterized by comprising a quartz crystal plate and a single-plate thermistor with an operating electrode formed on its surface, and the quartz crystal plate and the thermistor are housed in a single package.

[0011] The crystal plate has an excitation electrode formed on its surface, and the thermistor is also a single plate with an operating electrode formed on its surface. Because both are single plate in this way, when there is heat conduction from the outside through the package, temperature rise and fall information is transmitted to the crystal plate and thermistor with little time lag. This minimizes the difference between the temperature detected by the thermistor (temperature sensor) and the temperature of the crystal plate, allowing accurate and appropriate temperature compensation processing based on the frequency information of the crystal plate and the temperature information of the thermistor.

[0012] Furthermore, when the electrode film is formed on the quartz crystal plate and thermistor by a PVD film forming method such as sputtering or vacuum deposition, a thin film structure can be realized and the thermal conductivity of the electrode film can be improved.

[0013] The thermistor may have electrodes formed on the surface of a single thermistor plate, or may have a pair of working electrodes spaced apart from each other on one main surface. By passing a current through these working electrodes, the thermistor function (detection of a change in current based on temperature) is obtained.

[0014] A relay electrode may also be provided on the other main surface of the thermistor plate. The relay electrode may be formed in a position facing the working electrode on the front and back of the main surface. In this way, a terminal serving as a resistor is formed between a pair of working electrodes formed on the thermistor plate, and a conductive path flows from one of the working electrodes to the other working electrode via the relay electrode. This configuration greatly increases the cross-sectional area of ​​the conductive path, and also allows the working electrodes and the relay electrodes to face each other, thereby reducing the resistance value with a small area, facilitating stable characteristics, and improving the withstand voltage.

[0015] The relay electrode may be made of a metal having good thermal conductivity and may be formed over substantially the entire other main surface of the thermistor plate.

[0016] With this configuration, the relay electrode functions as a heat transfer section for the heat transferred to the working electrode of the thermistor, making it possible to minimize the time lag in detecting temperature changes.

[0017] The single-plate thermistor may have a thickness of 0.05 mm or less.

[0018] By making the thickness of the thermistor 0.05 mm or less, the heat (temperature fluctuation information) transmitted to the working electrode is quickly transmitted through the thermistor plate, improving the temperature detection ability of the thermistor.

[0019] The conductive bonding used here may be a conductive resin adhesive for both the quartz crystal plate and the thermistor, and further, the same resin material may be used for both the resin adhesives.

[0020] The package can be configured in a variety of ways. For example, the package may have one storage section, in which the crystal plate and the thermistor are conductively joined.

[0021] The above-mentioned configuration of housing the crystal oscillating plate and the thermistor in one housing section allows the crystal oscillating plate and the thermistor to be mounted in close proximity to each other, thereby making it possible to reduce the difference in thermal fluctuation between the two.

[0022] Furthermore, by using a conductive resin adhesive inside one of the housings, gas is less likely to be generated after bonding, and the characteristics of the quartz crystal plate can be stabilized. Conventionally, the conductive bonding of stacked thermistors was performed by solder bonding, but residual flux and the like could contaminate the atmosphere inside the package. However, by using a conductive resin adhesive to bond the two together as described above, the atmosphere inside the package, for example a vacuum or inert gas atmosphere, can be stabilized, and the characteristics of the quartz crystal plate (the operation of the quartz crystal unit) can be stabilized.

[0023] Furthermore, by using the same conductive resin adhesive, the difference in thermal conduction can be eliminated, and the temperature detection accuracy can be improved.

[0024] As a package storage configuration, the package may have two storage sections that open above and below a substrate, the quartz crystal plate being conductively joined to one of the storage sections and the thermistor being conductively joined to the other storage section, and the quartz crystal plate and the thermistor being arranged facing each other on the front and back of the substrate.

[0025] By arranging the quartz crystal plate and the thermistor facing each other on the front and back sides of the substrate, the difference in thermal conduction between the two can be eliminated, improving the accuracy of temperature detection.

[0026] The quartz crystal plate may be an AT-cut or SC-cut quartz crystal plate, or may be an XY-cut quartz crystal plate, or the like. Effect of the Invention

[0027] According to the present invention, it is possible to obtain a crystal resonator device with a temperature sensor that is compatible with ultra-small and ultra-thin designs, that properly detects temperature fluctuations associated with the crystal resonator device, and that has excellent electrical characteristics. [Brief description of the drawings]

[0028] [Figure 1] FIG. 2 is an exploded perspective view showing each component of the quartz crystal vibration device with a thermistor according to the first embodiment. [Diagram 2] FIG. 2 is a bottom view of FIG. 1 when assembled. [Diagram 3] FIG. 2 is a cross-sectional view taken along line AA of FIG. 1 when assembled. [Figure 4] 3A and 3B are diagrams showing an electrode film configuration formed on a quartz crystal plate. [Diagram 5] 3A and 3B are diagrams showing an electrode film configuration formed on a thermistor; [Figure 6] FIG. 11 is a cross-sectional view according to a second embodiment. [Figure 7] FIG. 11 is a cross-sectional view according to a third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0029] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[0030] First embodiment 1 to 3, the crystal vibration device Xtl with thermistor according to the first embodiment includes a package 1 having an upper storage section 11A and a lower storage section 11B, a crystal vibration plate 2 stored in the upper storage section 11A, a thermistor 4 stored in the lower storage section 11B, and a lid 3 that hermetically seals the upper storage section 11A. Note that FIG. 3 is a cross-sectional view taken along line AA in FIG. 2.

[0031] Package Composition 3, the package 1 is made of ceramics and has a rectangular parallelepiped shape as a whole, with an upper storage section 11A that opens upward and a lower storage section 11B that opens downward. The upper storage section 11A and the lower storage section 11B are configured so that their closed portions (bottoms) face back to back with respect to the substrate 11C.

[0032] The upper storage section 11A is a concave rectangular parallelepiped storage structure that opens upward, and mounting electrodes 16, 17 made of a metal film are formed on the bottom of the upper storage section 11A. These mounting electrodes 16, 17 are formed side by side in the short side direction of the package. In addition, a rectangular sealing section 10 is provided at a position higher than the bottom on the outer periphery of the upper storage section 11A, and a metal film layer is formed on the sealing section 10.

[0033] Each of the mounting electrodes 16 and 17 is made of multiple metal layers, and is laminated in the order of a W (tungsten) layer, a Ni (nickel) layer, and a Au (gold) layer. The W layer is integrally formed by firing together with the ceramic material constituting the package, and the Ni layer and the Au layer are formed on the W layer by plating. The sealing part 10 also has a metal layer configuration similar to that of the mounting electrodes 16 and 17, and has a laminated configuration of a W layer, a Ni layer, and a Au layer. Note that the mounting electrodes 18 and 19 and the mounting electrodes 12, 13, 14, and 15 described later are also manufactured by the same manufacturing method, and each has a layer configuration in which a W layer, a Ni layer, and a Au layer are laminated in this order.

[0034] The lower storage section 11B has a concave rectangular parallelepiped storage configuration that opens downward, and mounting electrodes 18, 19 made of metal film are formed on the bottom of the lower storage section 11B. These mounting electrodes 18, 19 are rectangular in shape with long and short sides, and are formed so that the long sides of both mounting electrodes face each other in the direction along the long side of the package. These mounting electrodes may also be formed so that they are aligned in the direction along the short side of the package.

[0035] Further, mounting electrodes 12, 13, 14, and 15 are provided at the four corners of the lower storage section 11B, which are located higher than the bottom. Each of these mounting electrodes has a rectangular shape, and among these, mounting electrodes 12 and 14 are electrically connected to mounting electrodes 16 and 17, and mounting electrodes 13 and 15 are electrically connected to mounting electrodes 18 and 19 by internal wiring of the package 1.

[0036] <Structure of the quartz crystal plate> The quartz crystal plate 2 is an AT-cut quartz crystal plate, and is generally rectangular. The quartz crystal plate 1 has excitation electrodes 21 and 22 formed in the center of the front and back of the quartz crystal plate 1, and these excitation electrodes 21 and 22 are drawn to the outer periphery of the quartz crystal plate by strip-shaped lead electrodes 21a and 22a having a width. The excitation electrodes 21 and 22 are rectangular, and the excitation electrode 21 on one main surface of the quartz crystal plate is drawn from one short corner to the short side of the one main surface of the quartz crystal plate by the lead electrode 21a, and the excitation electrode 22 on the other main surface of the quartz crystal plate is drawn from one short corner to the short side of the other main surface of the quartz crystal plate by the lead electrode 22a. As a result, the lead electrodes 21a and 22a are drawn to one short side of the quartz crystal plate.

[0037] These excitation electrodes 21, 22 and extraction electrodes 21a, 22a are configured by laminating thin metal films, specifically, as shown in Fig. 4, a Ti (titanium) layer is formed in contact with the quartz crystal plate, and an Au (gold) layer is formed on top of that. Note that the metal film configuration may be other than the above, and for example, a well-known metal configuration may be used, such as a Cr (chromium) layer as the base metal or an Ag (silver) layer as the upper layer.

[0038] By forming a Ti layer or Cr layer in contact with the quartz crystal plate, the metal film adheres well to the quartz crystal plate, forming a stable foundation for the excitation electrode. In addition, by forming an Au layer as the main layer on the surface, the long-term quality stability of the excitation electrode film is ensured, and the thermal conductivity is also good, so that changes in the environmental temperature can be transmitted to the quartz crystal plate with little time lag.

[0039] In addition, a configuration (formation of a functional layer) that improves adhesion with the conductive resin adhesive described below may be adopted by using an Au layer as the main layer and forming an extremely thin Cr layer on top of it, or by exposing the lower base metal layer to the upper layer by thermal diffusion.

[0040] These excitation electrodes and extraction electrodes are obtained by integrally laminating metal film layers of both electrodes by a well-known PVD film formation method such as vacuum deposition or sputtering.

[0041] In this embodiment, an AT-cut quartz crystal plate is used as the quartz crystal plate, but an SC-cut quartz crystal plate or an XY-cut tuning-fork-type quartz crystal plate may also be used.

[0042] <Thermistor configuration> The thermistor 4 functions as a temperature sensor, and is a thin, single-plate NTC thermistor as a whole. The thermistor 4 is based on a rectangular thermistor blank 40, and has a thickness G2. Rectangular operating electrodes 41, 42 are formed on one main surface of the thermistor blank 40 at a fixed interval G1 in the long side direction. These operating electrodes 41, 42 are rectangular with long and short sides, and the long sides have dimensions corresponding to the short side dimensions of the thermistor blank. A rectangular relay electrode 43 is formed on the entire other main surface of the thermistor blank 40.

[0043] The thermistor 4 constitutes an electronic component having terminals as a resistor with one working electrode 41 and the other working electrode 42 formed on the thermistor base plate 40, and a conductive path runs from the one working electrode 41 to the other working electrode 42 via the relay electrode 43. With this configuration, the cross-sectional area of ​​the conductive path can be greatly increased and the surfaces of the working electrode and the relay electrode can be opposed to each other, so that the resistance value can be reduced with a small area, the characteristics tend to be stable, and the withstand voltage can be improved.

[0044] Incidentally, when the operating electrodes 41 and 42 are in a configuration where they are close to each other, although it also depends on the voltage to be applied, the direct flow path from the operating electrode 41 to 42 becomes dominant in the conductive path, and there are cases where the desired resistance value cannot be obtained. Therefore, in practice, the distance G2a between the operating electrode 41 and the relay electrode 43, the distance G2b between the operating electrode 42 and the relay electrode 43, and the distance G1 between the operating electrodes 41 and 42 are set such that G2a + G2b < G1. With such a setting, the desired resistance value can be obtained, and the accuracy as a temperature sensor can be stabilized.

[0045] Also, the larger the contact area of the thermistor 4 with the package 1 and the closer it is arranged to the crystal diaphragm, the more accurately the temperature of the crystal diaphragm can be detected. Therefore, from the aspect of temperature measurement, it is preferable that the operating electrodes formed on the thermistor are larger with respect to the area of the thermistor substrate. This can increase the contact area. However, if the area is too large, short circuits between adjacent operating electrodes or short circuits due to conductive bonding materials are likely to occur. Also, if the contact area becomes small, the temperature detection accuracy of the crystal diaphragm decreases.

[0046] Therefore, although it also depends on the desired resistance value, when the total area of each operating electrode is 40% to 85% of the area of one main surface of the thermistor substrate, stable temperature detection can be performed. If it is less than 40%, the operating electrodes of the thermistor become too small, and the temperature information of the crystal diaphragm cannot be accurately detected, and the resistance value of the thermistor becomes too high, which may reduce the temperature detection ability as a temperature sensor. Also, if it is 85% or more, the risk of short circuits including the above-mentioned conductive bonding materials increases, and when a short circuit occurs, it no longer functions as a temperature sensor.

[0047] Next, specific dimension examples of the thermistor are shown below. The outer dimensions of the thermistor are 0.8 mm for the long side, 0.6 mm for the short side, and 0.05 mm for the thickness, and its area is 0.48 mm2. Also, the outer dimensions of each electrode pad formed on the thermistor substrate are 0.52 mm for the long side (on the short side of the thermistor substrate) and 0.3 mm for the short side (on the long side of the thermistor substrate), and its area is 0.156 mm2. With such a configuration, the total area of each electrode pad is set to about 65% of the area of the temperature sensor. Also, the distance G2a between the electrode pad and the relay electrode and the distance G2b between the electrode pad 42 and the relay electrode 43 are each 0.05 mm, and the distance G1 between the electrode pads is set to 0.12 mm, and it is set so that G2a + G2b < G1 holds.

[0048] Another specific example is shown below. The outer dimensions of the thermistor are 0.7 mm for the long side, 0.6 mm for the short side, and 0.04 mm for the thickness, and its area is 0.42 mm2. Also, the outer dimensions of each electrode pad formed on the thermistor substrate are 0.58 mm for the long side (on the short side of the thermistor substrate) and 0.3 mm for the short side (on the long side of the thermistor substrate), and its area is 0.174 mm2. With such a configuration, the total area of each electrode pad is set to about 83% of the area of the temperature sensor. Also, the distance G2a between the electrode pad and the relay electrode and the distance G2b between the electrode pad 42 and the relay electrode 43 are each 0.04 mm, and the distance G1 between the electrode pads is set to 0.09 mm, and it is set so that G2a + G2b < G1 holds. Note that the above dimensions may be appropriately designed according to the size and characteristics of the crystal vibration device and the required specifications of the crystal vibration device with a temperature sensor.

[0049] A single-plate thermistor is made, for example, by making a slurry of an Mn-Fe-Ni-Ti-based material together with a binder or the like, creating a green sheet of the thermistor wafer using a thick film forming technique such as screen printing technology or doctor blade technology, and sintering and forming a plate-shaped thermistor wafer by a firing technique.

[0050] An electrode film (metal film) is formed on this single-plate thermistor wafer by sputtering, and patterned using photolithography technology. A specific metal film layer (metal material) may have a laminated film structure, as shown in Figure 5, in which a Ti (titanium) layer is formed as a base layer in contact with the thermistor substrate, a TiO2 (titanium oxide) layer is formed as a barrier layer on top of that, a NiTi layer made of an alloy of Ni (nickel) and Ti is formed on top of that, and an Au (gold) layer is formed as the main layer on the surface.

[0051] The use of a laminated film structure of the Ti, TiO2, NiTi, and Au layers has the advantage that when the thermistor is finally soldered to a mounting board, solder erosion is unlikely to occur and stable conductive bonding can be achieved. Note that the above laminated structure may be configured without forming the TiO2 layer.

[0052] The metal film configuration of the electrode pads 41, 42 and the metal film configuration of the relay electrode 43 may be different. For example, the metal film configuration of the electrode pads 41, 42 may be a laminated configuration of the Ti film, the NiTi film, and the Au film, and the metal film configuration of the relay electrode may be a laminated configuration of the Ti film and the Au film. As examples of the thickness of the metal film, for the working electrodes 41, 42, the Ti film may be 2500 Å, the NiTi film may be 1500 Å, and the Au film may be 1500 Å. For the relay electrode 43, the Ti film may be 50 Å and 1500 Å. The thickness of the working electrodes 41, 42 may be the same as that of the relay electrode, that is, the Ti film may be 50 Å and 1500 Å. In this case, the working electrode and the relay electrode can be formed at the same time in the same film forming environment.

[0053] Alternatively, a laminated film configuration may be used in which a Cr (chromium) layer is formed in contact with the thermistor plate, a NiCr layer made of an alloy of a Ni layer and a Cr layer is formed on top of that, and an Au (gold) layer is formed as the topmost layer.

[0054] By forming a Ti layer or Cr layer in contact with the thermistor plate, the metal film adheres well to the quartz crystal plate, forming a stable foundation for the excitation electrode. In addition, by forming an Au layer on the top layer, the long-term quality stability of the excitation electrode film is ensured, and the thermal conductivity is also good, so that changes in the environmental temperature can be transmitted to the thermistor plate with little time lag.

[0055] In addition, a configuration may be adopted in which an Au layer is used as the upper layer and an extremely thin Cr layer is formed on top of it, or the lower base metal layer is exposed to the upper layer by thermal diffusion, thereby improving the adhesion with the conductive resin adhesive described below.

[0056] In this way, by forming a thin metal film on a single-plate thermistor blank by PVD deposition such as sputtering or vacuum deposition, an extremely thin plate thermistor can be obtained. The surface roughness of the plate thermistor may be reduced by lapping and polishing the surface of the thermistor wafer. This configuration allows the electrode film (metal film) to be stably formed and manufacturing precision to be improved, resulting in high-precision performance as a temperature sensor.

[0057] By making the thermistor plate a single plate, heat input from the working electrode etc. can be brought to the input heat temperature in a short time. In other words, the single plate thermistor 4 can detect external temperature changes with little time lag. In particular, by setting the thickness of the thermistor plate to 0.05 mm or less, the heat (temperature fluctuation information) transmitted to the working electrode is transmitted quickly through the thermistor plate, allowing it to respond to external temperature changes extremely quickly.

[0058] Furthermore, by using Au for the working electrodes and relay electrodes formed on the thermistor plate, good thermal conductivity can be achieved, and coupled with the single-plate structure of the thermistor plate described above, external temperature changes can be detected with little time lag.

[0059] In addition, in this embodiment, the metal film used in the relay electrode provided on the other main surface of the thermistor plate functions as a heat transfer portion, thereby improving the thermal response speed of the entire thermistor and enabling external temperature changes to be detected with little time lag.

[0060] In particular, in a configuration in which an Au layer is used as the main layer of the working electrode and relay electrode, the heat transfer performance can be improved, making it possible to detect external temperature changes with less time lag.

[0061] <Airtight sealing with lid> The lid 3 is made of a thin metal plate or ceramic plate, and has a rectangular shape corresponding to the outer size of the sealing part 10 of the package. The configurations of the lid and the sealing part differ depending on the method of hermetic sealing of the package. For example, when the lid 3 and the sealing part 10 are joined by seam welding, the lid uses Kovar as the core material, and a Ni plating film is formed on the surface. The sealing part is configured by brazing a ring-shaped metal frame, and the lid and the metal frame are joined by seam welding in a vacuum atmosphere or an inert gas atmosphere, for example. This allows the inside of the package (inside the upper storage part) to be in a steady state of a vacuum atmosphere or an inert gas atmosphere.

[0062] When hermetically sealing is performed by brazing with a metal brazing material, for example, an AuSn brazing material, a preform of the AuSn brazing material is formed around the lid, and the upper layer of the sealing portion is plated with Au. By heating both of them in a predetermined atmosphere and temperature environment, a hermetic seal can be achieved by metal brazing.

[0063] <Assembly of a crystal resonator device with a thermistor> An example of an assembly of the crystal resonator device Xtl with a thermistor will be described below. A paste-like conductive resin adhesive S1 is applied to the mounting electrodes 16, 17 of the upper storage section 11A of the package using a dispenser or the like. The conductive resin adhesive S1 is made of, for example, a silicone resin adhesive containing a metal filler, but other resin materials such as a polyimide-based resin material may also be used.

[0064] The quartz crystal diaphragm 2 with electrodes formed thereon is mounted on the applied conductive resin adhesive. Specifically, the quartz crystal diaphragm is mounted in the upper storage section so that the extraction electrodes 21a, 22a are bonded to the conductive resin adhesive S1. The conductive resin adhesive is then heated to harden the quartz crystal diaphragm 2 and the mounting electrodes 16, 17, forming a conductive bond (electrical and mechanical bond). Note that the conductive resin adhesive may be reapplied on top of the quartz crystal diaphragm, if necessary. In this embodiment, a configuration in which the adhesive is reapplied is shown as an example.

[0065] Next, the upper storage section is hermetically sealed by the lid, which is achieved by joining the lid 3 to the sealing section. In this embodiment, the metal brazing material sealing is achieved by a metal brazing material (AuSn brazing material) S2.

[0066] Thereafter, the thermistor is conductively joined to the lower housing portion. A conductive resin adhesive S1 is applied onto the mounting electrodes 18, 19 using a dispenser or the like, and the thermistor is mounted in the lower housing portion so that the operating electrodes 41, 42 correspond to the conductive resin adhesive. The conductive resin adhesive is then hardened by heating to conductively join (electrically and mechanically join) the thermistor 4 to the mounting electrodes 18, 19. Note that the conductive joining of the thermistor may be achieved by soldering.

[0067] Then, a resin material is injected into the lower housing portion using a dispenser or the like to cover the thermistor 4 with the resin material M, and then the resin material M is hardened by heating. In this embodiment, a polyimide resin is used as the resin material M, but other resin materials may also be used. This protects the thermistor from the outside air, allowing for stable temperature detection.

[0068] When the conductive bonding of the thermistor is performed by solder bonding, it is preferable that the Ti film has a thickness of about 2500 Å, the NiTi film has a thickness of 1500 Å, and the Au film has a thickness of about 1500 Å. After solder bonding, the Au layer on the surface of the working electrode may be eaten up by the solder and disappear from the electrode film configuration, but the necessary electrical bonding can be ensured by the bonding portion, the NiTi film, and the Ti film of the underlayer. A TiO2 film with a thickness of about 5 to 30 Å may be formed on the upper surface of the Ti film. In this case, the Ti layer of the underlayer can be protected from the solder.

[0069] Note that the resin material M may not be used, or may be injected only into the bottom of the lower storage section. In the case of injecting only into the bottom, the mounting electrodes 18, 19 and the operating electrodes 41, 42, which are joined with a conductive resin adhesive, are covered and protected by the resin material, and the relay electrode 43 is exposed. This ensures the joining strength of the thermistor 4, and allows the ambient temperature to be detected with little time lag.

[0070] After that, the crystal resonator device with thermistor Xtl is completed after undergoing the required characteristic inspection.

[0071] In the first embodiment, both the quartz crystal plate and the thermistor are single-plate structures, and an electrode film made of a metal film layer is formed on the surface of the quartz crystal plate. The main layer of both metal film layers is made of the same Au. With this structure, even if there is heat conduction through the package, for example, temperature rise information and temperature fall information are transmitted to the quartz crystal plate and thermistor with little time lag. As a result, the difference between the temperature detected by the thermistor, which is a temperature sensor, and the temperature of the quartz crystal plate is minimized, and temperature compensation processing based on the frequency information of the quartz crystal plate and the temperature information of the thermistor can be performed accurately and appropriately.

[0072] Second embodiment The second embodiment will be described with reference to FIG. In the second embodiment, a crystal vibration plate 2 and a thermistor 4 are housed inside a storage section of a package 5. The package 5 is made of ceramic with internal wiring formed therein, and has a storage section 51 with an opening at the top. Mounting electrodes 54, 55 (55 not shown) for the crystal vibration plate and mounting electrodes 56, 57 for the thermistor are formed on the bottom of the storage section 51. Mounting electrodes 52, 53 are formed on the bottom surface.

[0073] The quartz crystal plate 2 is made of a rectangular AT-cut quartz crystal plate as in the first embodiment, and has excitation electrodes 21, 22 and extraction electrodes 21a, 22a (not shown) formed on both main surfaces. The thermistor 4 has a pair of operating electrodes 41, 42 formed at a predetermined distance on one main surface, and does not have the relay electrodes shown in the first embodiment. The electrode films of the quartz crystal plate and thermistor are formed by PVD film formation such as sputtering. The quartz crystal plate 2 and thermistor 4 are then bonded with the same conductive resin adhesive S1, and are conductively bonded to the mounting electrodes by heat curing. They are then hermetically sealed and bonded by the lid 3.

[0074] In the second embodiment, a single-plate quartz crystal vibration plate and a single-plate thermistor are mounted in parallel in one storage section. In addition, electrodes are formed on both plates by a metal film layer using Au as the main layer by PVD deposition. This allows both plates to change temperature without time lag in response to changes in environmental temperature, and also allows the height of the thermistor-equipped quartz crystal vibration device to be reduced. In addition, since the conductive bonding is performed using the same conductive resin adhesive, the internal atmosphere after hermetically sealing is stable and the fluctuation of characteristics can be suppressed. In addition, since the adhesive can be heated and cured in a single process, productivity is excellent and costs can be reduced.

[0075] Third embodiment The third embodiment will be described with reference to FIG. In the third embodiment, the crystal plate 2 and thermistor 4 are stored side by side in the height direction inside the storage section of the package 6. The package 6 is made of ceramic with internal wiring formed therein, and has a storage section 61 with an opening at the top. A step 61a is provided in the storage section 61, and mounting electrodes 62, 63 (63 is not shown) are formed on the step. Furthermore, mounting electrodes 64, 65 for the thermistor are formed on the bottom of the storage section 61. Mounting electrodes 67, 68 are formed on the bottom surface.

[0076] The quartz crystal plate 2 is made of an AT-cut quartz crystal plate as in the first embodiment, and has excitation electrodes 21, 22 and extraction electrodes 21a, 22a (not shown) formed on both main surfaces. The thermistor 4 has a pair of operating electrodes 41, 42 formed at a predetermined interval on one main surface, and a relay electrode 43 is provided on the entire other main surface. In the third embodiment, the pair of operating electrodes are each rectangular with long and short sides, but have non-electrode parts 41a, 42a where the ends of the electrode film do not reach the ends of the thermistor plate. With this configuration, even if the amount of conductive resin adhesive applied is too large, it is unlikely to reach the relay electrode formed on the upper part, and short circuits between the electrodes due to the conductive resin adhesive can be prevented. The non-electrode part may be provided on the outer periphery of the relay electrode side.

[0077] Furthermore, in the third embodiment, relay electrodes are arranged below the excitation electrodes 21 and 22 formed on the quartz crystal plate, and combined with the lid, which will be described later, being made of a metal material, the quartz crystal plate is sandwiched between metal materials from above and below, providing an electromagnetic shielding effect that prevents external noise from reaching the quartz crystal plate.

[0078] The electrode film of the crystal diaphragm and thermistor is formed by PVD deposition such as sputtering. The crystal diaphragm 2 and thermistor 4 are bonded with the same conductive resin adhesive S1, and are conductively bonded to the mounted electrodes by heat curing. After that, the lid 3 is attached and hermetically sealed.

[0079] In the third embodiment, a single-plate quartz crystal plate with electrodes formed by PVD film formation and a single-plate thermistor are mounted vertically side by side in one storage section. This allows the temperature of both to change without time lag in response to changes in the environmental temperature. In addition, since the conductive bonding is performed using the same conductive resin adhesive, the internal atmosphere after hermetically sealing is stable and fluctuations in characteristics can be suppressed. In addition, since the adhesive can be heated and cured all at once, productivity is excellent and costs can be reduced.

[0080] The embodiments disclosed herein are illustrative in all respects and are not intended to be limiting. Therefore, the technical scope of the present invention is not interpreted solely by the above-described embodiments, but is defined by the claims. Also, all modifications within the scope and meaning equivalent to the claims are included. [Explanation of symbols]

[0081] 1,5,6 Package 11A Upper storage area 11B Lower storage area 12,13,14,15,52,53,67,68 Mounting electrodes 16,17,18,19,54,55,56,57,62,63,64,65 Mounted electrodes 2 Crystal diaphragm 21,22 Excitation electrode 3 Lid 4 Thermistor 41,42 Working electrode 43 Relay electrode S1 Conductive resin adhesive S2 Brazing metal M Resin material

Claims

1. A single crystal vibration plate having an excitation electrode formed on its surface; a single-plate thermistor having an operating electrode formed on a surface thereof; A quartz crystal resonator device with a thermistor, characterized in that the quartz crystal resonator plate and the thermistor are housed in a single package.

2. 2. The quartz crystal resonator device with thermistor according to claim 1, wherein the package has one housing portion, and the quartz crystal resonator plate and the thermistor are conductively joined to the housing portion.

3. The quartz crystal vibration device with thermistor according to claim 1, characterized in that the package has two storage sections that open above and below the substrate, the quartz crystal vibration plate is conductively bonded to one of the storage sections and the thermistor is conductively bonded to the other storage section, and the quartz crystal vibration plate and the thermistor are arranged facing each other on the front and back of the substrate.

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