JP6835607B2 - Crystal device and its manufacturing method - Google Patents

Description

The present invention relates to a crystal device used in an electronic device or the like and a method for manufacturing the same.

A crystal device uses the piezoelectric effect of a crystal element to generate a specific frequency. For example, the substrate, the first frame provided on the upper surface of the substrate to provide the first recess, the second frame provided on the lower surface of the substrate to provide the second recess, and the upper surface of the substrate are provided. A crystal device including a crystal element mounted on the electrode pad and an integrated circuit element mounted on the lower surface of the substrate has been proposed (see, for example, Patent Document 1 below).

Japanese Unexamined Patent Publication No. 2000-49560

Conventional crystal devices are remarkably miniaturized, but their packages are also miniaturized. In the miniaturized crystal device, via conductors for connecting the external terminal and the wiring pattern are formed at the four corners of the second recess. When such a crystal device is mounted on a mounting substrate of an electronic device or the like, the conductive bonding material attached to the external terminal enters the second recess from the external terminal via the via conductor, so that the crystal device is conductive. Since the amount of the bonding material is also reduced, the thickness of the conductive bonding material may be reduced, and the bonding strength may be lowered.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a crystal device capable of suppressing a decrease in bonding strength when mounted on a mounting substrate of an electronic device.

The crystal device according to one aspect of the present invention includes a substrate having a rectangular shape in a plan view, a first frame body provided along the outer peripheral edge of the upper surface of the substrate, and a first frame provided along the outer peripheral edge of the lower surface of the substrate. The two frames, the crystal element mounted on the electrode pad provided on the upper surface of the substrate, the integrated circuit element mounted on the connection pad provided on the lower surface of the substrate, and the connection pad provided on the lower surface of the substrate. An electrically connected connection pattern, an external terminal provided on the lower surface of the second frame, a via conductor electrically connected to the connection pattern and the external terminal, and a lid joined to the first frame. The via conductors are provided at the four corners of the inner peripheral edge of the second frame body, and have convex portions formed on the external terminals at the locations where the external terminals and the via conductors overlap in a plan view. doing.

The crystal device according to one aspect of the present invention includes a substrate having a rectangular shape in a plan view, a first frame body provided along the outer peripheral edge of the upper surface of the substrate, and a first frame provided along the outer peripheral edge of the lower surface of the substrate. The two frames, the crystal element mounted on the electrode pad provided on the upper surface of the substrate, the integrated circuit element mounted on the connection pad provided on the lower surface of the substrate, and the connection pad provided on the lower surface of the substrate. An electrically connected connection pattern, an external terminal provided on the lower surface of the second frame, a via conductor electrically connected to the connection pattern and the external terminal, and a lid joined to the first frame. The via conductors are provided at the four corners of the inner peripheral edge of the second frame body, and have convex portions formed on the external terminals at the locations where the external terminals and the via conductors overlap in a plan view. doing. When such a crystal device is mounted on a mounting substrate of an electronic device or the like, the bonding material attached to the external terminal is blocked by a convex portion provided on the external terminal, and the inside of the second concave portion is formed via a via conductor. It is possible to prevent it from getting in. Therefore, since the amount of the bonding material that enters the second recess can be reduced, the thickness of the bonding material attached to the external terminal can be maintained, and the bonding strength can be maintained.

It is an exploded perspective view which shows the crystal device which concerns on this embodiment. (A) is a sectional view taken along the line AA of FIG. 1, and FIG. 1B is a sectional view taken along the line BB of FIG. It is a partially enlarged view which enlarged the part of the convex part of the package which comprises the crystal device which concerns on this embodiment. (A) is a perspective plan view seen from the upper surface of the package constituting the crystal device according to the present embodiment, and (b) is a perspective plan view seen from the upper surface of the substrate of the package constituting the crystal device according to the present embodiment. It is a figure. (A) is a perspective perspective view of the lower surface of the package constituting the crystal device according to the present embodiment, and (b) is a perspective view of the crystal device according to the present embodiment as viewed from the lower surface. It is sectional drawing which shows the crystal device which concerns on the 1st modification of this embodiment.

As shown in FIGS. 1 and 2, the crystal device in the present embodiment includes a package 110, a crystal element 120 bonded to the upper surface of the package 110, and an integrated circuit element 150 bonded to the lower surface of the package 110. And is included. The package 110 is formed with a first recess K1 surrounded by an upper surface of the substrate 110a and an inner surface of the first frame 110b. Further, a second recess K2 surrounded by the lower surface of the substrate 110a and the inner surface of the second frame 110c is formed. Such a crystal device is used to output a reference signal used in an electronic device or the like.

The substrate 110a has a rectangular shape, and is for mounting the crystal element 120 mounted on the upper surface and the integrated circuit element 150 mounted on the lower surface. The substrate 110a is provided with an electrode pad 111 for mounting the crystal element 120 on the upper surface, and a connection pad 116 for mounting the integrated circuit element 150 on the lower surface. Further, an electrode pad 111 for joining the crystal element 120 is provided along one side of the substrate 110a. External terminals 112 are provided at the four corners of the lower surface of the second frame body 110c. Further, as shown in FIG. 5, a pair of measurement pads 118 are provided in the center of the lower surface of the substrate 110, and the integrated circuit element 150 is mounted so as to surround the pair of measurement pads 118. Two connection pads 116 are provided. Further, the external terminals 112 are electrically connected to the four external terminals inside the connection pad 116.

The substrate 110a is made of an insulating layer which is a ceramic material such as alumina ceramics or glass-ceramics. The substrate 110a may be one in which one layer of insulating layers is used, or one in which a plurality of layers of insulating layers are laminated. On the surface and inside of the substrate 110a, as shown in FIG. 3, wiring for electrically connecting the electrode pad 111 provided on the upper surface and the measuring pad 118 provided on the lower surface of the substrate 110a. A pattern 113 and a via conductor 114 are provided. Further, on the surface of the substrate 110a, a connection pattern 117 for electrically connecting the connection pad 116 and the measurement pad 118 provided on the lower surface and the external terminal 112 provided on the lower surface of the second frame body 110c is provided. It is provided.

The first frame body 110b is arranged on the upper surface of the substrate 110a, and is for forming the first recess K1 on the upper surface of the substrate 110a. The first frame 110b is made of a ceramic material such as alumina ceramics or glass-ceramics, and is integrally formed with the substrate 110a.

The second frame body 110c is arranged on the lower surface of the substrate 110a, and is for forming the second recess K2 on the lower surface of the substrate 110a. The second frame 110c is made of, for example, a ceramic material such as alumina ceramics or glass-ceramics, and is integrally formed with the substrate 110a.

The electrode pad 111 is for mounting the crystal element 120. A pair of electrode pads 111 are provided on the upper surface of the substrate 110a, and are provided adjacent to each other along one side of the substrate 110a. As shown in FIGS. 4 and 5, the electrode pad 111 is provided with an external terminal 112 provided on the lower surface of the second frame 110c via a wiring pattern 113 provided on the upper surface of the substrate 110a and a conductor portion 114. Is electrically connected to.

As shown in FIG. 4, the electrode pad 111 is composed of a first electrode pad 111a and a second electrode pad 111b. The conductor portion 114 is composed of a first conductor portion 114a and a second conductor portion 114b. Further, the wiring pattern 113 is composed of the first wiring pattern 113a and the second wiring pattern 113b.

Further, the first electrode pad 111a is electrically connected to one end of the first wiring pattern 113a provided on the substrate 110a. Further, the other end of the first wiring pattern 113a is electrically connected to the first measurement pad 118a described later via the first conductor portion 114a. Therefore, the first electrode pad 111a is electrically connected to the first measurement pad 118a. The second electrode pad 111b is electrically connected to one end of the second wiring pattern 113b provided on the substrate 110a. Further, the other end of the second wiring pattern 113b is electrically connected to the second measurement pad 118b, which will be described later, via the second via conductor 114b. Therefore, the second electrode pad 111b is electrically connected to the second measurement pad 118b.

The external terminal 112 is for mounting on a mounting board of an electronic device or the like. The external terminals 112 are provided at the four corners of the lower surface of the second frame body 110c. The external terminals 112 are electrically connected to four of the six connection pads 116 provided on the lower surface of the substrate 110a. Further, the third external terminal 112c is connected to a mounting pad connected to a ground potential which is a reference potential on a mounting board of an electronic device or the like. As a result, the lid 130 joined to the sealing conductor pattern H is connected to the third external terminal 112c, which has a ground potential. Therefore, the shielding property in the first recess K1 by the lid body 130 is improved. Further, the first external terminal 112a is used as an output terminal, the second external terminal 112b is used as a functional terminal, and the fourth external terminal 112d is used as a power supply voltage terminal. The functional terminals are used as write / read terminals and frequency control terminals. Here, the write / read terminal is a terminal for writing the temperature compensation control data to the storage element unit and reading the temperature compensation control data written in the storage element unit. The frequency control terminal is a terminal for correcting the temperature characteristics of the crystal element by changing the load capacitance of the variable capacitance diode of the oscillation circuit unit when a voltage is applied.

As shown in FIG. 5B, the external terminals 112 are provided at the four corners of the lower surface of the second frame body 110c, and are the first external terminal 112a, the second external terminal 112b, the third external terminal 112c, and the fourth external terminal. It is composed of 112d. The external terminal 112 is electrically connected to each of the connection pads 116 provided on the lower surface of the substrate 110a. Further, the third external terminal 112c is electrically connected to the sealing conductor pattern H via the conductor portion 114c described later and the third via conductor 119c described later. Therefore, the third external terminal 112c is used as a ground terminal.

The wiring pattern 113 is provided on the upper surface of the substrate 110a and is drawn out from the electrode pad 111 toward the via conductor 114 of the nearby substrate 110a. Further, as shown in FIG. 3, the wiring pattern 113 is composed of the first wiring pattern 113a and the second wiring pattern 113b.

The conductor portion 114 is provided inside the substrate 110a, and both ends thereof are electrically connected to the wiring pattern 113 and the measurement pad 118. The conductor portion 114 is provided by filling the inside of the through hole provided in the substrate 110a with a conductor. The conductor portion 114 is composed of a first conductor portion 114a, a second conductor portion 114b, and a third conductor portion 114c. The third conductor portion 114c is provided on the first frame body 110b and is electrically connected to the sealing conductor pattern H.

The protrusion 115 is for suppressing the vertical inclination of the short side of the crystal element 120 and preventing the end on the long side of the crystal element 120 from coming into contact with the substrate 110a or the lid 130. Further, the protrusion 115 is for suppressing the free end of the crystal element 120 from coming into contact with the substrate 110a. The pair of protrusions 115 is composed of a first protrusion 115a and a second protrusion 115b. The first protrusion 115a is provided on the upper surface of the first electrode pad 111a, and the second protrusion 115b is provided on the upper surface of the second electrode pad 111b. Further, the protrusion 115 is provided by subjecting the upper surface of a sintered body of a metal powder such as tungsten, molybdenum, copper, silver or silver palladium to gold plating or nickel plating, similarly to the electrode pad 111.

Further, one side of the pair of protrusions 115 facing the center side of the substrate 110a is provided so as to be aligned on the same straight line as shown in FIG. 4A. By doing so, when the extraction electrode 123 of the crystal element 120 is mounted on the electrode pad 111 while being in contact with the pair of protrusions 115, the crystal element 120 can be mounted in a stable state without tilting. Further, the length of the side of the protrusion 115 formed along the outer peripheral edge of the electrode pad 111 in the long side direction is 150 to 200 μm, and the length of the side of the protrusion 115 in the short side direction is 50 to. It is 75 μm. The length of the vertical thickness of the protrusion 115 is 20 to 75 μm. The length of the protrusion 115 in the long side direction is 150 to 300 μm, and the length of the side of the protrusion 115 in the short side direction is 50 to 75 μm. The length of the vertical thickness of the protrusion 115 is 20 to 75 μm.

Further, the protrusion 115 is provided at a position facing the extraction electrode 123 on the outer peripheral edge of the crystal element 120. By doing so, when the crystal element 120 is mounted on the electrode pad 111 via the conductive adhesive 140, even if the crystal element 120 is tilted, the extraction electrode 123 comes into contact with the protrusion 115. Therefore, the crystal element 120 can be mounted in a stable state without tilting downward from the protrusion 115. Further, the protrusion 115 is provided at a position where it overlaps with the extraction electrode 123 on the outer peripheral edge of the quartz base plate 121 on the fixed end side in a plan view. By doing so, it is possible to reduce the contact of the fixed end of the crystal element 120 with the upper surface of the substrate 110a.

The connection pad 116 is used to mount the integrated circuit element 150. Further, as shown in FIG. 5, the connection pad 116 is formed by the first connection pad 116a, the second connection pad 116b, the third connection pad 116c, the fourth connection pad 116d, the fifth connection pad 116e, and the sixth connection pad 116f. It is configured. The first connection pad 116a and the first external terminal 112a are connected by a first connection pattern 117a described later and a first via conductor 119a described later provided on the lower surface of the substrate 110a, and the second connection pad 116b and the first external terminal 112a are connected to each other. (2) The measurement pad 118b is electrically connected. Further, the third connection pad 116c and the second external terminal 112b are connected by a second connection pattern 117b described later and a second via conductor 119b described later provided on the lower surface of the substrate 110a, and the fourth connection pad 116d And the third external terminal 112c are connected by a third connection pattern 117c described later and a third via conductor 119c described later provided on the lower surface of the substrate 110a. Further, the fifth connection pad 116e and the first measurement pad 118a are electrically connected, and the sixth connection pad 116f and the fourth external terminal 112d are connected to the fourth connection described later, which is provided on the lower surface of the substrate 110a. It is connected by a pattern 117d and a fourth via conductor 119d described later. Further, the connection pattern 117 is provided on the lower surface of the substrate 110a and is drawn out from the connection pad 116 toward the nearby external terminal 112.

The connection pattern 117 is for electrically connecting the connection pad 116 and the external terminal 112. The connection pattern 117 is composed of a first connection pattern 117a, a second connection pattern 117b, a third connection pattern 117c, and a fourth connection pattern 117d.

The measuring pad 118 is for measuring the characteristics of the crystal element 120 by bringing the contact pins and the like of the crystal element 120 into contact with each other. The measurement pad 118 is composed of a first measurement pad 118a and a second measurement pad 118b. The measurement pad 118 is electrically connected to the electrode pad 111 provided on the upper surface of the substrate 110a via the wiring pattern 113 and the conductor portion 114 provided on the substrate 110a. The measurement pad 118 is provided at a position where it overlaps with the integrated circuit element 150 in a plan view. By doing so, the stray capacitance generated between the mounting pattern (not shown) on the mounting board of an electronic device or the like and the measurement pad 118 is reduced, so that the stray capacitance is not added to the crystal element 120. , It is possible to reduce the fluctuation of the oscillation frequency of the crystal element 120.

The via conductor 119 is for electrically connecting the connection pattern 117 and the external terminal 112. As shown in FIG. 5, the via conductors 119 are provided at the four corners of the inner peripheral edge of the second frame body 110c, and both ends thereof are electrically connected to the connection pattern 117 and the external terminal 112. The via conductor 119 is provided by filling the inside of the through hole provided in the substrate 110a with a conductor. The via conductor 119 is composed of a first via conductor 119a, a second via conductor 119b, a first via conductor 119c, and a fourth via conductor 119d. The upper end of the third via conductor 119c is electrically connected to the third conductor 114c, so that it is electrically connected to the lid 130 via the sealing conductor pattern H. Further, a convex portion T is provided on the external terminal 112 at a position where the external terminal 112 and the via conductor 119 overlap each other in a plan view.

Further, the convex portion T can prevent a bonding material (not shown) such as solder used when mounting the crystal device from entering the second concave portion K2 via the via conductor 119. As shown in FIG. 5B, the convex portion T is provided at the external terminal 112 at a position where the external terminal 112 and the via conductor 119 overlap each other in a plan view. When the via conductor 119 is formed, the convex portion T is formed so as to bulge from the lower surface side of the second frame body 110c as shown in FIG. 3, and the convex portion T is formed by providing the external terminal 112 on the upper surface thereof. Can be done. The convex portion T is composed of a first convex portion T1, a second convex portion T2, a third convex portion T3, and a fourth convex portion T4.

By providing the convex portion T in this way, when the crystal device is mounted on a mounting substrate such as an electronic device, the bonding material (not shown) attached to the external terminal 112 is provided on the external terminal 112. It is possible to prevent the portion T from being blocked by the physical action of forming a dam and entering the second recess K2 via the via conductor 119. Since the bonding material gets into the second recess K2, it is possible to reduce the adhesion between the connection terminals 151 of the integrated circuit element 150, so that a short circuit can be suppressed. Further, since the amount of the bonding material that enters the second recess K2 can be reduced, the thickness of the bonding material attached to the external terminal 112 can be maintained, and the bonding strength can be maintained.

Further, the convex portion T is formed in a columnar shape. By doing so, when mounting on a mounting board of an electronic device or the like, the bonding material (not shown) adhering to the external terminal 112 wraps around the outside of the convex portion T along the side surface of the cylinder. It is possible to further suppress the entry into the second recess K2. Further, since the convex portion T has a convex shape toward the upper side of the mounting substrate of an electronic device or the like, the bonding material attached to the external terminal 112 crawls on the via conductor 119 as compared with the concave shape or the flat shape. It can be difficult to raise.

Further, the shape of the convex portion T in a plan view is the same as the shape of the via conductor 119 in a plan view. When such a crystal device is mounted on a mounting substrate such as an electronic device, the stress applied to the convex portion T is evenly applied to the via conductor 119, so that the interface between the via conductor 119 and the second frame 110b is peeled off. Can be suppressed, and poor continuity can be reduced.

The sealing conductor pattern H plays a role of improving the wettability of the joining member 131 when joining the lid body 130 via the joining member 131. As shown in FIGS. 3 and 4, the sealing conductor pattern H is electrically connected to the third external terminal 112c via the third conductor portion 114c and the third via conductor 119c. The sealing conductor pattern H has a thickness of, for example, 10 to 25 μm by sequentially applying nickel plating and gold plating to the surface of a conductor pattern made of, for example, tungsten or molybdenum, in a form of circularly surrounding the upper surface of the first frame 110b. Is formed in.

Here, the size of the measurement pad 118 will be described by taking the case where the size of one side when the package 110 is viewed in a plan view is 1.0 to 2.0 mm as an example. The length of the long side of the measuring pad 118 is 0.5 to 0.8 mm, and the length of the short side is 0.45 to 0.75 mm.

Further, as an electrical characteristic measuring instrument (not shown) used when measuring the characteristics of the crystal element 120, it is necessary to measure equivalent parameters such as inductance and capacitance in addition to the resonance frequency and crystal impedance of the crystal element 120. A network analyzer or impedance analyzer that can be used is used. The contact pin is composed of a highly conductive pin in which the surface of an alloy such as copper or silver is plated with gold, and a resectorable socket having a spring property that suppresses an impact at the time of contact. The measurement is performed by making contact while pressing against.

Here, a method for manufacturing the substrate 110a will be described. When the substrate 110a is made of alumina ceramics, first, a plurality of ceramic green sheets obtained by adding and mixing an appropriate organic solvent or the like to a predetermined ceramic material powder are prepared. Further, a predetermined conductor paste is applied to the surface of the ceramic green sheet or the through hole which has been punched or the like in advance by punching or the like to the ceramic green sheet by a conventionally known screen printing or the like. Further, these green sheets are laminated and press-molded, and then fired at a high temperature. Finally, a predetermined portion of the conductor pattern, specifically, an electrode pad 111, an external terminal 112, a wiring pattern 113, a conductor portion 114, a protrusion 115, a connection pad 116, a connection pattern 117, a measurement pad 118, a via conductor 119, and the like. It is produced by subjecting the portion to be the sealing conductor pattern H to nickel plating, gold plating, silver palladium, or the like. Further, the conductor paste is composed of, for example, a sintered body of a metal powder such as tungsten, molybdenum, copper, silver or silver-palladium.

As shown in FIGS. 1 and 2, the crystal element 120 is bonded onto the electrode pad 111 via a conductive adhesive 140. The crystal element 120 plays a role of oscillating a reference signal of an electronic device or the like by stable mechanical vibration and a piezoelectric effect.

Further, as shown in FIGS. 1 and 2, the crystal element 120 has a structure in which the excitation electrode 122 and the extraction electrode 123 are adhered to the upper surface and the lower surface of the quartz base plate 121, respectively. .. The excitation electrode 122 is formed by adhering and forming metal on the upper surface and the lower surface of the quartz plate 121 in a predetermined pattern. The excitation electrode 122 includes a first excitation electrode 122a on the upper surface and a second excitation electrode 122b on the lower surface. The extraction electrode 123 extends from the excitation electrode 122 toward one side of the quartz plate 121. The extraction electrode 123 includes a first extraction electrode 123a on the upper surface and a second extraction electrode 123b on the lower surface. The first extraction electrode 123a is drawn out from the first excitation electrode 122a and is provided so as to extend toward one side of the quartz base plate 121. The second extraction electrode 123b is drawn out from the second excitation electrode 122b and is provided so as to extend toward one side of the quartz base plate 121. That is, the lead-out electrode 123 is provided in a shape along the long side or the short side of the quartz base plate 121. Further, in the present embodiment, one end of the crystal element 120 connected to the first electrode pad 111a and the second electrode pad 111b is a fixed end connected to the upper surface of the substrate 110a, and the other end is between the upper surface of the substrate 110a. The crystal element 120 is fixed on the substrate 110a by a cantilever support structure having a free end.

Here, the operation of the crystal element 120 will be described. In the crystal element 120, when an alternating voltage from the outside is applied from the extraction electrode 123 to the crystal base plate 121 via the excitation electrode 122, the crystal base plate 121 is excited in a predetermined vibration mode and frequency. ing.

Here, a method of manufacturing the crystal element 120 will be described. First, the crystal element 120 is cut from an artificial crystalline lens at a predetermined cut angle to reduce the thickness of the outer circumference of the crystal base plate 121, and the central portion of the crystal base plate 121 becomes thicker than the outer peripheral portion of the crystal base plate 121. Bevel processing is performed so as to be provided. Then, the crystal element 120 is manufactured by forming the excitation electrode 122 and the extraction electrode 123 by adhering a metal film on both main surfaces of the crystal base plate 121 by a photolithography technique, a vapor deposition technique, or a sputtering technique. Will be done.

A method of joining the crystal element 120 to the substrate 110a will be described. First, the conductive adhesive 140 is applied onto the first electrode pad 111a and the second electrode pad 111b by, for example, a dispenser. The crystal element 120 is conveyed on the conductive adhesive 140 and placed on the conductive adhesive 140. Then, the conductive adhesive 140 is cured and shrunk by being heat-cured. The crystal element 120 is joined to the electrode pad 111. That is, the second lead-out electrode 123b of the crystal element 120 is joined to the second electrode pad 111b, and the first pull-out electrode 123a is joined to the first electrode pad 111a.

The conductive adhesive 140 contains a conductive powder as a conductive filler in a binder such as a silicone resin, and the conductive powder includes aluminum, molybdenum, tungsten, platinum, palladium, silver, and titanium. Any of nickel and nickel iron, or those containing a combination thereof are used. Further, as the binder, for example, a silicone resin, an epoxy resin, a polyimide resin or a bismaleimide resin is used.

As the integrated circuit element 150, for example, a rectangular flip-chip type integrated circuit element having a plurality of connection pads is used, and a temperature sensor for detecting an ambient temperature state, a crystal, is used on the circuit forming surface (upper surface) thereof. A storage element unit for storing temperature compensation data that compensates for the temperature characteristics of the element 120, a temperature compensation circuit unit that corrects the vibration characteristics of the crystal element 120 according to a temperature change based on the temperature compensation data, and a temperature compensation circuit unit thereof. An oscillation circuit unit that is connected to and generates a predetermined oscillation output is provided. The output signal generated by the oscillation circuit unit is output to the outside of the temperature-compensated crystal oscillator via the first external terminal 112a of the package 110, and is used as a reference signal such as a clock signal.

The storage element unit is composed of a PROM or an EEPROM. The temperature compensation control data of the parameters that are the basis of the cubic function shown below, which is the temperature compensation function, such as the cubic component adjustment value α, the primary component adjustment value β, and the 0th component adjustment value γ, is the second external terminal. It is input and saved from the write / read terminal which is 112b. A register map is stored in the storage element unit. The register map shows what kind of operation is performed by the control unit reading the data and outputting the signal when the control data is input to each address data.

The temperature compensation circuit unit is composed of a cubic function generation circuit, a quintic function generation circuit, and the like. For example, in the case of a cubic function generation circuit, the temperature compensation control data input to the storage element unit is read out, and the voltage derived by the cubic function is generated for each temperature from the temperature compensation control data. The external ambient temperature at this time is obtained from the temperature sensor in the integrated circuit element 150. The temperature compensation circuit unit is connected to the cathode of the variable capacitance diode, and the voltage from the temperature compensation circuit unit is applied. In this way, the frequency temperature characteristic is flattened by correcting the frequency temperature characteristic of the crystal element 120 by applying the voltage from the temperature compensation circuit unit to the variable capacitance diode.

As shown in FIG. 2, the integrated circuit element 150 is mounted on a connection pad 116 provided on the lower surface of the substrate 110a via a conductive bonding material 160 such as solder. Further, the connection terminal 151 of the integrated circuit element 150 is connected to the connection pad 116. The connection pad 116 is electrically connected to the external terminal 112 via the connection pattern 117. The third external terminal 112c serves as a ground terminal by being connected to a mounting pad connected to a ground which is a reference potential on a mounting board of an electronic device or the like. Therefore, one of the connection terminals 151 of the integrated circuit element 150 is connected to the ground which is the reference potential.

Further, the temperature sensor provided in the integrated circuit element 150 is provided so as to be located in the measurement pad 118 in a plan view. By doing so, the heat transferred from the crystal element 120 and the heat transferred from the electrode pad 111 to the measurement pad 118 via the wiring pattern 113 and the via conductor 114 are dissipated from the measurement pad 118, and the integrated circuit element 150 It will be transmitted to the temperature sensor installed inside. Therefore, since the temperature-compensated crystal oscillator can shorten the heat conduction path, the temperature of the crystal element 120 and the temperature of the integrated circuit element 150 become close to each other, and the temperature sensor of the integrated circuit element 150 is obtained. It is possible to further reduce the difference between the temperature and the actual ambient temperature of the crystal element 120.

Further, as shown in FIGS. 1 and 2, the integrated circuit element 150 has a rectangular shape, and six connection terminals 151 are provided on the lower surface thereof. Three connection terminals 151 are provided along one side, and three are provided along one side facing the one side. The length of the long side of the integrated circuit element 150 is 0.5 to 1.2 mm, and the length of the short side is 0.3 to 1.0 mm. The length of the integrated circuit element 150 in the thickness direction is 0.1 to 0.3 mm.

The conductive bonding material 160 is made of, for example, silver paste or lead-free solder. Further, the conductive bonding material contains an added solvent for adjusting the viscosity so that it can be easily applied. The component ratio of lead-free solder is 95 to 97.5% for tin, 2 to 4% for silver, and 0.5 to 1.0% for copper.

The lid 130 is made of, for example, an alloy containing at least one of iron, nickel or cobalt. Such a lid 130 is for airtightly sealing the first recess K1 in a vacuum state or the first accommodating portion K1 filled with nitrogen gas or the like. Specifically, the lid body 130 is placed on the first frame body 110b of the package 110 in a predetermined atmosphere, and the sealing conductor pattern H of the first frame body 110b and the joining member 131 of the lid body 130 are formed. By applying a predetermined current so as to be welded and performing seam welding, the first frame body 110b is joined. Further, the lid body 130 is electrically connected to the third external terminal 112c on the lower surface of the second frame body 110c via the sealing conductor pattern H, the third conductor portion 114c and the third via conductor 119c. Therefore, the lid body 130 is electrically connected to the third external terminal 112c of the second frame body 110c.

The joining member 131 is provided at a position of the lid 130 facing the sealing conductor pattern H provided on the upper surface of the first frame 110b of the package 110. The joining member 131 is provided with, for example, silver wax or gold tin. In the case of silver wax, its thickness is 10 to 20 μm. For example, a component ratio of 72 to 85% for silver and 15 to 28% for copper is used. In the case of gold tin, its thickness is 10 to 40 μm. For example, those having a component ratio of 78 to 82% for gold and 18 to 22% for tin are used.

The crystal device in the present embodiment is provided along the rectangular substrate 110a in a plan view, the first frame 110b provided along the outer peripheral edge of the upper surface of the substrate 110a, and the outer peripheral edge of the lower surface of the substrate 110a. The second frame 110c, the crystal element 120 mounted on the electrode pad 111 provided on the upper surface of the substrate 110a, the integrated circuit element 150 mounted on the connection pad 116 provided on the lower surface of the substrate 110a, and the substrate 110a. The connection pattern 117 provided on the lower surface of the second frame and electrically connected to the connection pad 116, the external terminal 112 provided on the lower surface of the second frame body 110c, and the connection pattern 117 and the external terminal 112 are electrically connected. The via conductor 119 and the lid 130 joined to the first frame body 110b are provided, and the via conductor 119 is provided at four corners of the inner peripheral edge of the second frame body 110c, and is provided with an external terminal 112 and vias. It has a convex portion T formed on an external terminal 112 at a position where the conductor 119 overlaps with the conductor 119 in a plan view.

In such a crystal device, when mounted on a mounting substrate of an electronic device or the like, a bonding material (not shown) attached to the external terminal 112 becomes a dam at a convex portion T provided on the external terminal 112. It is possible to prevent it from entering the second recess K2 via the via conductor 119 because it is blocked by the target action. Since the bonding material gets into the second recess K2, it is possible to reduce the adhesion between the connection terminals 151 of the integrated circuit element 150, so that a short circuit can be suppressed. Further, since the amount of the bonding material that enters the second recess K2 can be reduced, the thickness of the bonding material attached to the external terminal 112 can be maintained, and the bonding strength can be maintained.

Further, in the crystal device of the present embodiment, the convex portion T is formed in a columnar shape. By doing so, when mounting on a mounting board of an electronic device or the like, the bonding material (not shown) adhering to the external terminal 112 wraps around the outside of the convex portion T along the side surface of the cylinder. It is possible to further suppress the entry into the second recess K2. Further, since the convex portion T has a convex shape toward the upper side of the mounting substrate of an electronic device or the like, the bonding material attached to the external terminal 112 crawls on the via conductor 119 as compared with the concave shape or the flat shape. It can be difficult to raise.

Further, the crystal device in the present embodiment has the same shape when the convex portion T is viewed in a plan view as the shape in which the via conductor 119 is viewed in a plan view. When such a crystal device is mounted on a mounting substrate such as an electronic device, the stress applied to the convex portion T is evenly applied to the via conductor, so that the interface between the via conductor 119 and the second frame 110b is peeled off. It can be suppressed and the conduction failure can be reduced.

Further, the crystal device in the present embodiment has a measurement pad 118 provided on the lower surface of the substrate 110a, and the measurement pad 118 is provided at a position where it overlaps with the integrated circuit element 150 in a plan view. By doing so, the stray capacitance generated between the mounting pattern (not shown) on the mounting board of an electronic device or the like and the measurement pad 118 is reduced, so that the stray capacitance is not added to the crystal element 120. , It is possible to reduce the fluctuation of the oscillation frequency of the crystal element 120.

(First modification)
Hereinafter, the crystal device in the first modification of the present embodiment will be described. Of the crystal devices in the first modification of the present embodiment, the same parts as those of the crystal device described above are designated by the same reference numerals, and the description thereof will be omitted as appropriate. In the crystal device in the first modification of the present embodiment, as shown in FIG. 6, an insulating resin 170 is provided between the exposed portion of the via conductor 119 and the integrated circuit element 150 and the connection pad 116. It differs from the present embodiment in that it is provided.

Further, as shown in FIG. 6, the insulating resin 170 is provided on the exposed surface of the via conductor 119. By doing so, even if the bonding material (not shown) such as solder used when mounting the crystal device on the mounting substrate of the electronic device gets over the convex portion T, the via conductor 119 is exposed. Since the insulating resin 170 is coated on the surface, the bonding material is less likely to get wet and spread, so that it can be further suppressed from entering the second recess K2.

As shown in FIG. 6, the insulating resin 170 is provided between the surface of the integrated circuit element 150 where the connection terminal 151 is provided and the connection pad 116. By doing so, the insulating resin 170 can increase the adhesive strength between the integrated circuit element 150 and the lower surface of the substrate 110a. Further, even if a bonding material such as solder gets into the second recess K2 when the temperature-compensated crystal oscillator is mounted on the mounting pad of the mounting board of an electronic device or the like, the insulating resin 170 provides the insulating resin 170. Since it is possible to prevent the bonding material from adhering between the connection terminals 151 of the integrated circuit element 150, it is possible to reduce a short circuit between the connection terminals 151 of the integrated circuit element 150. Further, the insulating resin 170 is made of a resin material such as an epoxy resin or a composite resin containing an epoxy resin as a main component.

Further, the insulating resin 170 is provided so as to cover the measurement pad 118. By doing so, it is possible to prevent foreign matter from adhering to the measurement pad 118, and thus it is possible to prevent the additional resistance of the foreign matter from being applied to the crystal element 120. Therefore, it is possible to reduce fluctuations in the oscillation frequency of the crystal element 120.

A method of forming the insulating resin 170 on the substrate 110a will be described. The tips of the resin dispenser are inserted into the four corners of the inner peripheral edge of the second frame portion 110c to inject the insulating resin 170. Next, the insulating resin 170 is heated and cured. Therefore, the insulating resin 170 is provided so as to cover the exposed surface of the via conductor 119. By doing so, even if the bonding material (not shown) such as solder used when mounting the crystal device on the mounting substrate of the electronic device gets over the convex portion T, the via conductor 119 is exposed. Since the insulating resin 170 is coated on the surface to be formed, the bonding material is less likely to get wet and spread, so that it can be further suppressed from entering the second recess K2.

In the crystal device in the first modification of the present embodiment, the insulating resin 170 is provided on the exposed surface of the via conductor 119. By doing so, even if the bonding material (not shown) such as solder used when mounting the crystal device on the mounting substrate of the electronic device gets over the convex portion T, the via conductor 119 is exposed. Since the insulating resin 170 is coated on the surface, the bonding material is less likely to get wet and spread, so that it can be further suppressed from entering the second recess K2.

Further, in the crystal device in the first modification of the present embodiment, an insulating resin 170 is provided between the integrated circuit element 150 and the connection pad 116. By doing so, the adhesive strength between the integrated circuit element 150 and the lower surface of the substrate 110a can be increased. Further, since the adhesive resin 170 suppresses the bonding material from adhering between the connection terminals 151 of the integrated circuit element 150, it is possible to reduce the short circuit between the connection terminals 151 of the integrated circuit element 150.

It should be noted that the present invention is not limited to this embodiment, and various changes and improvements can be made without departing from the gist of the present invention. In the above embodiment, the case where the crystal element for AT is used as the crystal element has been described, but the tuning fork type bent crystal having a base and two flat plate-shaped vibrating arms extending in the same direction from the side surface of the base. An element may be used.

110 ... Package 110a ... Substrate 110b ... First frame 110c ... Second frame 111 ... Electrode pad 112 ... External terminal 113 ... Wiring pattern 114 ... Conductor 115 ... Projection 116 ... Connection pad 117 ... Connection pattern 118 ... Measurement pad 119 ... Via conductor 120 ... Crystal element 121 ... Crystal base plate 122 ... Excitation electrode 123 ・ ・ ・ Pull-out electrode 130 ・ ・ ・ Lid 131 ・ ・ ・ Bonding member 140 ・ ・ ・ Conductive adhesive 150 ・ ・ ・ Integrated circuit element 151 ・ ・ ・ Connection terminal 160 ・ ・ ・ Conductive bonding material 170 ・ ・ ・・ Insulating resin H ・ ・ ・ Conductor pattern for sealing K1 ・ ・ ・ First concave part K2 ・ ・ ・ Second concave part T ・ ・ ・ Convex part

Claims (6)

A rectangular substrate in a plan view and
A first frame body provided along the outer peripheral edge of the upper surface of the substrate and
A second frame provided along the outer peripheral edge of the lower surface of the substrate, and
A crystal element mounted on an electrode pad provided on the upper surface of the substrate, and
An integrated circuit element mounted on a connection pad provided on the lower surface of the substrate, and
A connection pattern provided on the lower surface of the substrate and electrically connected to the connection pad,
External terminals provided on the lower surface of the second frame and
A via conductor in which the connection pattern and the external terminal are electrically connected,
A lid body joined to the first frame body and
The via conductors are provided at the four corners of the inner peripheral edge of the second frame body and are exposed on the inner peripheral side of the second frame body, and the external terminals and the via conductors overlap in a plan view. A crystal device characterized by having a convex portion formed on the external terminal in the above. The crystal device according to claim 1.
A crystal device characterized in that the convex portion is formed in a columnar shape. The crystal device according to claim 1.
A crystal device characterized in that the shape of the convex portion in a plan view is the same as the shape of the via conductor in a plan view. The crystal device according to claim 1.
It has a measurement pad provided on the lower surface of the substrate, and has.
A crystal device characterized in that the measurement pad is provided at a position where it overlaps with the integrated circuit element in a plan view. The crystal device according to claim 1.
A crystal device characterized in that an insulating resin is provided at an exposed portion of the via conductor. The crystal device according to claim 5.
A crystal device characterized in that the insulating resin is also provided between the integrated circuit element and the connection pad.

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