JP7679757B2 - Thermistor-equipped quartz crystal device - Google Patents

Description

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.

In recent years, with the increasing precision of various electronic devices, there is 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, which are crystal oscillators with a thermistor attached as a temperature sensor, are widely used.

By measuring the ambient temperature of the quartz crystal unit using a thermistor and transmitting frequency 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.

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.

The above thermistors have a laminated structure in which multiple layers of thermistor material and multiple layers of operating electrodes are stacked together, and those with a thickness of about 0.3 mm to 0.1 mm are commercially available and in use.

Patent No. 5900582

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 means that they require a certain thickness (height). This structure can result in a difference between the temperature of the quartz crystal unit and the temperature detected by the thermistor as a temperature sensor.

In such cases, the temperature of the crystal oscillator cannot be detected accurately, and appropriate temperature compensation cannot be performed in the temperature compensation circuit, making it impossible to provide an accurate frequency signal to the electronic device. This can reduce the operational reliability of the electronic device.

The present invention was made in consideration of the above problems, and aims to provide a crystal vibration device with a temperature sensor that is compatible with ultra-compact and ultra-thin designs, can stably and appropriately detect temperature fluctuations related to crystal vibration devices, and has excellent electrical characteristics.

The quartz crystal vibration device with thermistor according to the present invention is characterized in that it comprises a single quartz crystal vibration plate having an excitation electrode formed on its surface, a single thermistor having an operating electrode formed on its surface, and the quartz crystal vibration plate and the thermistor are housed in a single package.

An excitation electrode is formed on the surface of the quartz crystal plate, 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 quartz 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 quartz crystal plate, allowing accurate and appropriate temperature compensation processing based on the frequency information of the quartz crystal plate and the temperature information of the thermistor.

In addition, when the electrode film is formed on the quartz crystal plate and thermistor using a PVD film formation method such as sputtering or vacuum deposition, a thin film structure can be achieved and the thermal conductivity of the electrode film can be improved.

The above thermistor has electrodes formed on the surface of a single thermistor plate, and may have a pair of working electrodes spaced apart on one main surface. By passing a current through these working electrodes, the thermistor function (detection of current change based on temperature) is obtained.

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. This forms a terminal as a resistor 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, so that the resistance value can be reduced with a small area, characteristics can be stabilized, and the withstand voltage can be improved.

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

With this configuration, the relay electrode functions as a heat transfer section for the heat transferred to the working electrode of the thermistor, minimizing the time lag in detecting temperature changes.

The single-plate thermistor may also have a thickness of 0.05 mm or less.

By making the thermistor thickness 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.

The conductive bonding used here may be a conductive resin adhesive for both the conductive bonding of the quartz crystal plate and the conductive bonding of the thermistor. Furthermore, the resin adhesive used here may be the same resin material for both.

The package can be configured in a variety of ways, but for example, the package may have one storage section, and the quartz crystal plate and the thermistor are conductively joined to the storage section.

By storing them in a single storage compartment, the quartz crystal plate and thermistor can be mounted close to each other, thereby reducing the difference in thermal fluctuation between the two.

Furthermore, by using a conductive resin adhesive inside one of the storage compartments, gas is less likely to be generated after bonding, and the characteristics of the quartz crystal plate can be stabilized. Conventionally, conductive bonding of stacked thermistors was performed using 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, such as 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.

Furthermore, by using the same conductive resin adhesive, differences in thermal conductivity can be eliminated, improving temperature detection accuracy.

The package may have two storage sections, each opening above and below the substrate, with the quartz crystal plate conductively bonded to one storage section and the thermistor conductively bonded to the other storage section, with the quartz crystal plate and the thermistor positioned facing each other on the front and back of the substrate.

By arranging the quartz crystal plate and thermistor facing each other on the front and back of the substrate, the difference in thermal conductivity between the two is eliminated, improving the accuracy of temperature detection.

The quartz crystal plate may be an AT-cut or SC-cut quartz crystal plate, or an XY-cut quartz crystal plate, etc.

The present invention makes it possible to obtain a crystal vibration device with a temperature sensor that is compatible with ultra-compact and ultra-thin designs, can properly detect temperature fluctuations related to the crystal vibration device, and has excellent electrical characteristics.

FIG. 2 is an exploded perspective view showing each component of the quartz crystal vibration device with a thermistor according to the first embodiment. FIG. 2 is a bottom view of the assembled device shown in FIG. 1 . 2 is a cross-sectional view taken along line AA of FIG. 1 when assembled. 3A and 3B are diagrams showing an electrode film configuration formed on a quartz crystal plate. 3A and 3B are diagrams showing an electrode film configuration formed on a thermistor; FIG. 11 is a cross-sectional view according to a second embodiment. FIG. 11 is a cross-sectional view according to a third embodiment.

The following describes in detail the embodiments of the present invention with reference to the drawings.

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 A-A in FIG. 2.

Package Composition
3, the package 1 is made of ceramics and has a rectangular parallelepiped shape as a whole, and has 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) are back-to-back with respect to the substrate 11C.

The upper storage section 11A is a concave rectangular 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 on the outer periphery of the upper storage section 11A at a position higher than the bottom, and a metal film layer is formed on the sealing section 10.

Each mounting electrode 16, 17 is made of multiple metal layers, stacked 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 with the ceramic material that constitutes 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 structure similar to that of the mounting electrodes 16, 17, and has a stacked structure of a W layer, a Ni layer, and a Au layer. Note that the mounting electrodes 18, 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 structure in which a W layer, a Ni layer, and a Au layer are stacked in that order.

The lower storage section 11B is a concave rectangular 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. It is to be noted that both mounting electrodes may be formed so that they are lined up in the direction along the short side of the package.

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 mounting electrode has a rectangular shape, and 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.

<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.

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 well-known metal configurations may be used, such as a Cr (chromium) layer as the base metal and an Ag (silver) layer as the top layer.

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 the basis of a stable 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.

It is also possible to use an Au layer as the main layer and form an extremely thin Cr layer on top of it, or to use thermal diffusion to expose the lower metal base layer to the upper layer, thereby improving the adhesion with the conductive resin adhesive described below (forming a functional layer).

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

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 X-Y-cut tuning fork-type quartz crystal plate may also be used.

<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 constant 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.

The thermistor 4 is an electronic component having terminals as resistors, with one working electrode 41 and the other working electrode 42 formed on the thermistor base plate 40, and the conductive path flows from the one working electrode 41 to the other working electrode 42 via the relay electrode 43. This configuration significantly increases the cross-sectional area of the conductive path, and also allows the working electrode and the relay electrode to face each other, so that the resistance value can be reduced with a small area, characteristics can be stabilized, and the withstand voltage can be improved.

However, when the working electrodes 41 and 42 are arranged close to each other, depending on the applied voltage, the conductive path may be dominated by a direct flow path from working electrode 41 to 42, and the desired resistance value may not be obtained. Therefore, in practice, the distance G2a between working electrode 41 and relay electrode 43, the distance G2b between working electrode 42 and relay electrode 43, and the distance G1 between working electrodes 41 and 42 are set so as to satisfy G2a + G2b < G1. With such settings, the desired resistance value can be obtained and the accuracy as a temperature sensor can be stabilized.

Furthermore, the larger the contact area of the thermistor 4 with the package 1 and the closer it is positioned to the quartz crystal plate, the more accurately it can detect the temperature of the quartz crystal plate. From the perspective of temperature measurement, therefore, it is preferable that the operating electrodes formed on the thermistor are larger than the area of the thermistor plate. This allows the contact area to be large. However, if the area is too large, short circuits between adjacent operating electrodes or short circuits due to the conductive bonding material are more likely to occur. Furthermore, if the contact area is smaller, the accuracy of temperature detection of the quartz crystal plate decreases.

Thus, depending on the desired resistance value, stable temperature detection can be achieved if the total area of each working electrode is 40% to 85% of the area of one of the main surfaces of the thermistor plate. If it is less than 40%, the working electrodes of the thermistor will be too small, making it impossible to accurately detect the temperature information of the quartz crystal plate, and the resistance value of the thermistor will be too high, which may reduce its temperature detection ability as a temperature sensor. Furthermore, if it is more than 85%, there is an increased risk of a short circuit, including the conductive bonding material mentioned above, and if a short circuit occurs, it will no longer function as a temperature sensor.

The following is an example of the specific dimensions of the thermistor. The external dimensions of the thermistor are 0.8 mm long, 0.6 mm short, and 0.05 mm thick, giving an area of 0.48 mm2. The external dimensions of each electrode pad formed on the thermistor plate are 0.52 mm long (short side of the thermistor plate) and 0.3 mm short (long side of the thermistor plate), giving an area of 0.156 mm2. With this configuration, the total area of each electrode pad is set to approximately 65% of the area of the temperature sensor, and 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 set to 0.05 mm, and the distance G1 between the electrode pads is set to 0.12 mm, so that G2a + G2b < G1 holds.

Other specific examples are shown below. The external dimensions of the thermistor are 0.7 mm long, 0.6 mm short, and 0.04 mm thick, resulting in an area of 0.42 mm2. The external dimensions of each electrode pad formed on the thermistor plate are 0.58 mm long (short side of the thermistor plate) and 0.3 mm short (long side of the thermistor plate), resulting in an area of 0.174 mm2. With this configuration, the total area of each electrode pad is set to about 83% of the area of the temperature sensor, and 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 set to 0.04 mm, respectively, and the distance G1 between the electrode pads is set to 0.09 mm, so that G2a + G2b < G1 holds. The above dimensions may be designed appropriately according to the size and characteristics of the quartz crystal resonator device and the required specifications of the quartz crystal resonator device with temperature sensor.

Single-plate thermistors are made by, for example, making a slurry of Mn-Fe-Ni-Ti-based material with a binder, etc., and using a thick-film forming technique such as screen printing or doctor blade to create a green sheet of thermistor wafer, which is then sintered into a plate-shaped thermistor wafer using a firing technique.

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 be a laminated film configuration as shown in Figure 5, in which a Ti (titanium) layer is formed as a base layer in contact with the thermistor base plate, a TiO2 (titanium oxide) layer is formed as a barrier layer on top of that, a NiTi layer made of an alloy of a Ni (nickel) layer and a Ti layer is formed on top of that, and an Au (gold) layer is formed as a main layer on the surface.

When the laminated film structure of the Ti, TiO2, NiTi, and Au layers is adopted, there is an advantage that when the thermistor is finally soldered to the mounting board, solder erosion is unlikely to occur and a stable conductive bond can be achieved. Note that the above laminated structure may be configured without forming the TiO2 layer.

The metal film configuration of the electrode pads 41 and 42 may be different from that of the relay electrode 43. For example, the metal film configuration of the electrode pads 41 and 42 may be a laminated configuration of the Ti film, NiTi film, and Au film, and the metal film configuration of the relay electrode may be a laminated configuration of the Ti film and Au film. As an example of the thickness of the metal film, for the working electrodes 41 and 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 and 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 formation environment.

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 on the topmost layer.

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 the foundation for a stable 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.

It is also possible to use an Au layer as the upper layer and form an extremely thin Cr layer on top of it, or to use thermal diffusion to expose the lower metal base layer to the upper layer, thereby improving adhesion with the conductive resin adhesive described below.

In this way, by forming a thin metal film on a single-plate thermistor blank using PVD deposition methods such as sputtering or vacuum deposition, an extremely thin plate thermistor can be obtained. The surface roughness of the plate thermistor can be reduced by lapping and polishing the surface while it is in the thermistor wafer state. With this configuration, the electrode film (metal film) can be stably formed and manufacturing precision can be improved, resulting in high-precision performance as a temperature sensor.

By making the thermistor plate a single plate, the 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 for extremely fast response to external temperature changes.

In addition, by using Au for the operating electrodes and relay electrodes formed on the thermistor base plate, thermal conductivity can be improved, and combined with the single-plate structure of the thermistor base plate described above, external temperature changes can be detected with little time lag.

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 section, which improves the thermal response speed of the entire thermistor and allows external temperature changes to be detected with less time lag.

In particular, in configurations where Au layers are used as the main layers 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.

<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 airtight sealing method 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.

When hermetically sealing by soldering with a metal brazing material, such as AuSn brazing material, the AuSn brazing material is preformed around the lid, and the upper layer of the sealing portion is plated with Au. By heating both in a specified atmosphere and temperature environment, the hermetic seal can be achieved by metal brazing.

<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.

The quartz crystal vibration plate 2 with electrodes formed thereon is mounted on the applied conductive resin adhesive. Specifically, the quartz crystal vibration plate 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 vibration plate 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 vibration plate as necessary. In this embodiment, a configuration in which the adhesive is reapplied is shown as an example.

Then, the upper storage section is hermetically sealed by joining the lid 3 to the sealing section. In this embodiment, the metal brazing material sealing is performed using the metal brazing material (AuSn brazing material) S2.

Then, the thermistor is conductively joined to the lower storage section. 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 storage section so that the operating electrodes 41, 42 correspond to the conductive resin adhesive. The conductive resin adhesive is then hardened by heating, and the thermistor 4 and the mounting electrodes 18, 19 are conductively joined (electrically and mechanically joined). Note that the conductive joining of the thermistor may be achieved by soldering.

Then, resin material is injected into the lower storage section 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.

When the conductive bonding of the thermistor is performed by solder bonding, it is preferable to set the thickness of the Ti film as described above to about 2500 Å, the NiTi film to 1500 Å, and the Au film to about 1500 Å. After solder bonding, the Au layer on the surface of the working electrode may be eaten away by the solder and disappear from the electrode film configuration, but the necessary electrical bonding can be ensured by the joint, the NiTi film, and the Ti film as the base layer. A TiO2 film with a thickness of, for example, about 5 to 30 Å may be formed on the top surface of the Ti film. In this case, the Ti layer as the base layer can be protected from the solder.

Note that the resin material M may not be used, or may be injected only into the bottom of the lower storage section. In this case, 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 bonding strength of the thermistor 4, and allows the ambient temperature to be detected with little time lag.

Then, after undergoing the required characteristics inspection, the crystal resonator device with thermistor Xtl is completed.

In the first embodiment, both the quartz crystal plate and thermistor are of single-plate construction, with an electrode film made of a metal film layer formed on their surface. The main layer of both metal film layers is made of the same Au. With this construction, even when there is thermal conduction via the package, for example, temperature rise and fall information is 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 minimal, 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.

Second Embodiment A second embodiment will be described with reference to FIG.
In the second embodiment, the quartz crystal plate 2 and 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 is not shown) for the quartz crystal 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.

The quartz crystal plate 2 is made of a rectangular AT-cut quartz crystal plate as in the first embodiment, with 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 using a PVD film formation method 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 with the lid 3.

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 using a metal film layer with Au as the main layer by PVD deposition. This allows the temperature of both plates to change without time lag in response to changes in the 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 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.

Third Embodiment A 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. 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.

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 this third embodiment, the pair of operating electrodes are each rectangular with long and short sides, but non-electrode portions 41a, 42a are provided 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 portion may be provided on the outer periphery of the relay electrode side.

Furthermore, in this third embodiment, a relay electrode is arranged below the excitation electrodes 21, 22 formed on the quartz crystal plate, and combined with the lid described below being made of a metal material, the quartz crystal plate is sandwiched between metal materials from above and below. This provides an electromagnetic shielding effect that prevents external noise from reaching the quartz crystal plate.

The electrode film of the quartz crystal plate and thermistor is formed by PVD film formation methods 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 mounted electrodes by heat curing. They are then hermetically sealed and bonded with the lid 3.

In the third embodiment, a single-plate quartz crystal vibration plate with electrodes formed by PVD film formation and a single-plate thermistor are mounted side-by-side in a single storage section in a vertical direction. This allows the temperature of both to change without any time lag in response to changes in the environmental temperature. In addition, since the conductive bond is made with 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.

The embodiments disclosed herein are illustrative in all respects and are not intended to be a basis for a restrictive interpretation. Therefore, the technical scope of the present invention is not to be interpreted solely by the above-described embodiments, but is defined based on the claims. Furthermore, all modifications within the scope and meaning equivalent to the claims are included.

1, 5, 6 Package 11A Upper storage section 11B Lower storage section 12, 13, 14, 15, 52, 53, 67, 68 Mounting electrode 16, 17, 18, 19, 54, 55, 56, 57, 62, 63, 64, 65 Mounting electrode 2 Crystal plate 21, 22 Excitation electrode 3 Lid 4 Thermistor 41, 42 Operating electrode 43 Relay electrode S1 Conductive resin adhesive S2 Metal brazing material M Resin material

Claims (3)

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, comprising: the quartz crystal resonator plate and the thermistor housed in a single package. The quartz crystal vibration device with thermistor according to claim 1, characterized in that the package has one storage section, and the quartz crystal vibration plate and the thermistor are conductively joined to the storage section. The crystal vibration device with thermistor according to claim 1, characterized in that the package has two storage compartments that open above and below the substrate, the crystal vibration plate is conductively bonded to one storage compartment, the thermistor is conductively bonded to the other storage compartment, and the crystal vibration plate and the thermistor are arranged facing each other on the front and back of the substrate.

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