JP6795455B2 - Crystal device - Google Patents

Description

The present invention relates to a crystal device used in an electronic device or the like.

The crystal device uses the piezoelectric effect of the tuning fork type crystal element to generate a specific frequency. For example, a crystal device including a substrate, a package having a frame on the upper surface of the substrate for providing a recess, and a tuning fork type crystal element mounted on an electrode pad provided on the upper surface of the substrate. Known (see, for example, Patent Document 1 below)

Japanese Unexamined Patent Publication No. 2012-118920

The above-mentioned crystal device is remarkably miniaturized, but the mounted tuning fork type crystal element is also miniaturized. When the vibrating arm of such a tuning fork type crystal element comes into contact with the substrate, bending vibration may be hindered and the oscillation frequency may fluctuate.

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 fluctuations in the oscillation frequency of a tuning fork type crystal element.

The crystal device according to one aspect of the present invention includes a substrate, a first frame 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 upper surface of the first frame. A body, a third frame provided along the outer peripheral edge of the lower surface of the substrate, a pair of electrode pads provided along the short side direction on the substrate, a rectangular crystal base, and side surfaces of the crystal base. A sound fork-type crystal element having a more extended crystal vibrating portion, excitation electrodes provided on the upper and lower surfaces of the crystal vibrating portion, and a drawing electrode electrically connected to the exciting electrode, and provided on the lower surface of the substrate. The integrated circuit element mounted on the connection pad, the substrate and the first frame, the first recess provided between the electrode pads, the substrate and the first frame, and the crystal oscillator. It is provided with a second recess provided at a position facing the middle of the crystal unit, and a third recess formed by the substrate and the first frame and provided at a position facing the tip of the crystal oscillator.

The crystal device according to one aspect of the present invention includes a substrate, a first frame 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 upper surface of the first frame. A body, a third frame provided along the outer peripheral edge of the lower surface of the substrate, a pair of electrode pads provided along the short side direction on the substrate, a rectangular crystal base, and side surfaces of the crystal base. A sound fork-type crystal element having a more extended crystal vibrating portion, excitation electrodes provided on the upper and lower surfaces of the crystal vibrating portion, and a drawing electrode electrically connected to the exciting electrode, and provided on the lower surface of the substrate. The integrated circuit element mounted on the connection pad, the substrate and the first frame, the first recess provided between the electrode pads, the substrate and the first frame, and the crystal oscillator. It is provided with a second recess provided at a position facing the middle of the crystal unit, and a third recess formed by the substrate and the first frame and provided at a position facing the tip of the crystal oscillator. By doing so, when the tuning fork type crystal element is mounted on the electrode pad, even if the tuning fork type crystal element is tilted, it is possible to prevent the crystal vibrating part from coming into contact with the upper surface of the substrate. It is possible to suppress fluctuations and stops of the oscillation frequency of the type crystal element.

It is an exploded perspective view of the crystal device which concerns on this embodiment. FIG. 1 is a sectional view taken along the line AA of FIG. It is a top view which shows the tuning fork type crystal element which comprises the crystal device which concerns on this embodiment. (A) is a plan perspective view seen from the upper surface of the package constituting the crystal device according to the present embodiment, and (b) is a plan perspective view seen from the first frame side of the package constituting the crystal device according to the present embodiment. .. It is a plane perspective view seen from the upper surface of the substrate of the package which constitutes the crystal device which concerns on this embodiment. (A) A plan perspective view from the lower surface of the substrate of the package constituting the crystal device according to the present embodiment, and (b) a plane viewed from the lower surface of the third frame of the package constituting the crystal device according to the present embodiment. It is a perspective view.

(First Embodiment) The crystal device in the first embodiment includes a package 110 and a tuning fork type crystal element 120 mounted on the upper surface of the package 110, as shown in FIGS. 1 and 2. .. The package 110 is composed of a substrate 110a, a first frame body 110b, a second frame body 110c, and a third frame body 110d. The first recess K1, the second recess K2, and the third recess K3 are formed by the substrate 110a and the first frame 110b, and the fourth recess K4 is formed by the first frame 110b and the second frame 110c. There is. Further, the fifth recess K5 is formed by the substrate 110a and the third frame 110d. The tuning fork type crystal element 120 is provided with a crystal base 121 and a crystal vibration unit 123. 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 tuning fork type crystal element 120 mounted on the upper surface and the integrated circuit element 150 mounted on the lower surface.
The substrate 110a is
An electrode pad 111 for mounting the tuning fork type crystal element 120 is provided on the upper surface, and a connection pad 115 for mounting the integrated circuit element 150 is provided on the lower surface. Further, along one side of the substrate 110a, a first electrode pad 111a and a second electrode pad 111b for joining the tuning fork type crystal element 120 are provided. External terminals 112 are provided at the four corners of the lower surface of the third frame body 110d. Further, a pair of measurement pads 118 are provided in the center of the lower surface of the substrate 110a, and six connection pads 115 for mounting the integrated circuit element 150 are provided so as to surround the pair of measurement pads 118. Further, the external terminals 112 are electrically connected to the four external terminals inside the connection pad 115.

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. Wiring patterns 113 and via conductors 114 for electrically connecting the electrode pads 111 provided on the upper surface and the measurement pads 118 provided on the lower surface of the substrate 110a are provided on the surface and inside of the substrate 110a. There is. Further, on the surface of the substrate 110a, a connection pad 115 and a measurement pad 118 provided on the lower surface are provided.

The first frame body 110b is arranged on the upper surface of the substrate 110a, and is for forming the first recess K1, the second recess K2, and the third recess K3 on the upper surface of the substrate 110a. Further, the second frame body 110c is arranged on the upper surface of the first frame body 110b, and is for forming the fourth recess K4 on the upper surface of the first frame body 110b. The third frame body 110d is for forming a fifth recess K5 on the lower surface of the substrate 110a. The first frame body 110b, the second frame body 110c, and the third frame body 110d are made of a ceramic material such as alumina ceramics or glass-ceramics, and are integrally formed with the substrate 110a.

The first recess K1 is provided between the pair of electrode pads 111, and when the tuning fork type crystal element 120 described later is mounted, the contact of the conductive adhesive 140 provided on the pair of adjacent electrode pads 111 is provided. It is for suppressing. The first recess K1 is formed by the upper surface of the substrate 110a and the first frame 110b. By doing so, even if the conductive adhesive 140 provided on the pair of adjacent electrode pads 111 overflows from the electrode pads 111 when the tuning fork type crystal element 120 is mounted, the first recess K1 By entering the inside, it is possible to further prevent the adjacent electrode pads 111 from being short-circuited.

The second recess K2 is provided at a position facing the vibrating arm portion 122 of the tuning fork type crystal element 120 described later, and is for suppressing the vibrating arm portion 122 from coming into contact with the upper surface of the substrate 110a. The second recess K2 is formed by the upper surface of the substrate 110a and the first frame 110b, and is provided at a position facing the vibrating arm portion 122 of the tuning fork type crystal element 120. By doing so, when the tuning fork type crystal element 120 is mounted on the electrode pad 111, even if the tuning fork type crystal element 120 is tilted, the vibrating arm portion 122 is prevented from coming into contact with the upper surface of the substrate 110a. Therefore, it is possible to suppress fluctuations and stops of the oscillation frequency of the tuning fork type crystal element 120.

The third recess K3 is provided at a position facing the weight portion 128 of the tuning fork type crystal element 120 described later, and is for suppressing the weight portion 128 from coming into contact with the upper surface of the substrate 110a. The third recess K3 is formed by the upper surface of the substrate 110a and the first frame 110b, and is provided at a position facing the weight portion 128 of the tuning fork type crystal element 120. By doing so, when the tuning fork type crystal element 120 is mounted on the electrode pad 111, even if the tuning fork type crystal element 120 is tilted, the weight portion 128 is prevented from coming into contact with the upper surface of the substrate 110a. Therefore, it is possible to reduce fluctuations and stops of the oscillation frequency of the tuning fork type crystal element.

The fourth recess K4 is for mounting the tuning fork type crystal element 120, which will be described later. The fourth recess K4 is formed by the upper surface of the first frame 110b and the second frame 110c. The fifth recess K5 is for mounting an integrated circuit element described later. The fifth recess K5 is formed by the lower surface of the substrate 110a and the third frame 110d.

Further, the first recess K1 is provided so as to connect the space with the second recess K2 and the third recess K3. By doing so, even if the conductive adhesive 140 provided on the pair of adjacent electrode pads 111 overflows from the electrode pads 111 when the tuning fork type crystal element 120 is mounted, the first recess K1 It is possible to further prevent the adjacent electrode pads 111 from being short-circuited by entering the inside and flowing out from the first recess K1 through the second recess K2 to the third recess K3.

Further, when viewed in a plan view, the length parallel to the X-axis in the crystal axis direction of the first recess K1 is set to be smaller than the length parallel to the X-axis in the crystal axis direction of the second recess K2. The length parallel to the X-axis in the crystal axis direction of the second recess K2 is set to be smaller than the length parallel to the X-axis in the crystal axis direction of the third recess K3. By doing so, the occupied area of the first frame body 110b becomes smaller from the first recess K1 toward the third recess K3, so that the stress applied to the package 110 is smaller than that of the third recess K3. Since the amount of strain displacement in the electrode pad 111 provided on the upper surface of the first frame 110b near K1 is small, it is possible to prevent the tuning fork type crystal element 120 from peeling off from the electrode pad 111.

The electrode pad 111 is for mounting the tuning fork type 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. 1 and 4, the electrode pad 111 is provided with an external terminal 112 provided on the lower surface of the third frame body 110c via a wiring pattern 113 provided on the upper surface of the substrate 110a and a via conductor 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 via conductor 114 includes a first via conductor 114a, a second via conductor 114b, a third via conductor 114c, a fourth via conductor 114d, a fifth via conductor 114e, a sixth via conductor 114f, a seventh via conductor 114g, and an eighth via. It is composed of a conductor 114h. Further, the wiring pattern 113 is composed of a first wiring pattern 113a, a second wiring pattern 113b, a third wiring pattern 113c, and a fourth wiring pattern 113d. The measurement pad 118 is composed of a first measurement pad 118a and a second measurement pad 118b. 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 one end of the third wiring pattern 113c via the first via conductor 114a. The other end of the third wiring pattern 113c is electrically connected to the first measurement pad 118a via the seventh via conductor 114g. 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 one end of the fourth wiring pattern 113d via the second via conductor 114b. The other end of the fourth wiring pattern 113d is electrically connected to the second measurement pad 118b via the eighth via conductor 114h. Therefore, the second electrode pad 111b is electrically connected to the second measurement pad 118b.

Further, the first measurement pad 118a is electrically connected to the third connection pad 115c. Therefore, the first electrode pad 111a is electrically connected to the third connection pad 115c. Further, the second measurement pad 118b is electrically connected to the sixth connection pad 115f. Therefore, the second electrode pad 111b is electrically connected to the sixth connection pad 115f.

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 third frame body 110d. The external terminals 112 are electrically connected to four of the six connection pads 115 provided on the lower surface of the substrate 110a. Further, the first external terminal 112a 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 117 is connected to the first external terminal 112a, which has a ground potential. Therefore, the shielding property in the fourth recess K4 by the lid body 130 is improved. Further, the first external terminal 112a is used as a ground terminal, the second external terminal 112b is used as an output terminal, the third external terminal 112c is used as a functional terminal, and the fourth external terminal 112d is a power supply voltage. Used as a 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 tuning fork type crystal element 120 by changing the load capacitance of the variable capacitance diode of the oscillation circuit unit when a voltage is applied.

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. 4, the wiring pattern 113 is composed of a first wiring pattern 113a, a second wiring pattern 113b, a third wiring pattern 113c, and a fourth wiring pattern 113d.

The via conductor 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 via conductor 114 is provided by filling the inside of the through hole provided in the substrate 110a with a conductor. The via conductor 114 includes a first via conductor 114a, a second via conductor 114b, a third via conductor 114c, a fourth via conductor 114d, a fifth via conductor 114e, a sixth via conductor 114f, a seventh via conductor 114g, and an eighth via. It is composed of a conductor 114h.

The seventh via conductor 114g and the eighth via conductor 114h are provided so as to be located between the pair of crystal vibrating portions 123 when viewed in a plan view. By doing so, in order to suppress the generation of additional capacitance between the excitation electrodes 125 and 126 provided in the crystal vibrating portion 123 and the seventh via conductor 114g and the eighth via conductor 114h, the tuning fork type crystal It is possible to reduce fluctuations in the oscillation frequency of the element 120.

The connection pad 115 is used to mount the integrated circuit element 150. Further, as shown in FIG. 6, the connection pad 115 is provided by the first connection pad 115a, the second connection pad 115b, the third connection pad 115c, the fourth connection pad 115d, the fifth connection pad 115e, and the sixth connection pad 115f. It is configured. The first connection pad 115a is electrically connected to the first external terminal 112a, and the second connection pad 115b is electrically connected to the second external terminal 112b. The third connection pad 115c is electrically connected to the first measurement pad 118a, and the sixth connection pad 115f is electrically connected to the second measurement pad 118b. The fourth connection pad 115d is electrically connected to the third external terminal 112c, and the fifth connection pad 115e is electrically connected to the fourth external terminal 112d.

The sealing conductor pattern 117 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. 4 to 6, the sealing conductor pattern 117 is electrically connected to the first external terminal 112a via the third via conductor 114c. The sealing conductor pattern 117 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 second frame 110c. Is formed in.

The measuring pad 118 is for measuring the characteristics of the tuning fork type crystal element 120 by bringing the contact pin or the like into contact with the measuring pad 118. 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 on the mounting board of an electronic device or the like and the measurement pad 118 is reduced, and the stray capacitance is not added to the tuning fork type crystal element 120. It is possible to reduce fluctuations in the oscillation frequency of the crystal element 120.

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 used when measuring the characteristics of the tuning fork type crystal element 120, it is possible to measure equivalent parameters such as inductance and capacitance in addition to the resonance frequency and crystal impedance of the tuning fork type crystal element 120. A tuning fork, an impedance analyzer, or the like 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 of 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, nickel plating is performed on a predetermined portion of the conductor pattern, specifically, an electrode pad 111, an external terminal 112, a wiring pattern 113, a via conductor 114, a connection pad 115, a sealing conductor pattern 117, and a measurement pad 118. Further, it is produced by applying 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 to 3, the tuning fork type crystal element 120 includes a crystal base 121 and a crystal vibration unit 123. The surface of the tuning fork type crystal element 120 is composed of excitation electrodes 125a, 125b, 126a and 126b, extraction electrodes 127a and 127b, a weight portion 128 and a frequency adjustment electrode 129.

The crystal base 121 supports the crystal vibrating portion 123, which will be described later, and holds and fixes the tuning fork type crystal element 120 on the package 110. The crystal base 121 is within the range of −5 ° to + 5 ° around the X axis when the electric axis is the X axis, the mechanical axis is the Y axis, and the optical axis is the Z axis in a Cartesian coordinate system as the axial direction of the crystal. It is a flat plate having a substantially square shape in a plan view in which the direction of the Z'axis rotated by

The crystal vibration unit 123 is for exciting vibration of a desired frequency by forming excitation electrodes 125 and 126 having a desired pattern on the surface thereof and applying an electric potential to the excitation electrodes 125 and 126. is there. The crystal vibrating portion 123 is composed of a vibrating arm portion 122 and a weight portion 128. A hammer head-shaped weight portion 128 is provided at the tip of the vibrating arm portion 122, that is, at the end portion of the vibrating arm portion 122 opposite to the crystal base portion 121. Further, the crystal vibrating unit 123 includes a first crystal vibrating unit 123a and a second crystal vibrating unit 123b. The first crystal vibrating portion 123a and the second crystal vibrating portion 123b extend parallel to the direction of the Y'axis from one side of the crystal base 121. Further, the vibrating arm portion 122 is composed of a first vibrating arm portion 122a and a second vibrating arm portion 122b. Such a tuning fork type crystal element 120 is integrally formed with the crystal base portion 121 and each crystal vibrating unit 123 to form a tuning fork shape, and is manufactured by a photolithography technique and a chemical etching technique.

As shown in FIG. 3, the excitation electrode 125a is provided on the front and back main surfaces of the first vibrating arm portion 122a of the first crystal vibrating portion 123a. Further, the excitation electrodes 126b are provided on both side surfaces of the first crystal vibrating portion 123a facing the first vibrating arm portion 122a. Further, one of the extraction electrodes 127a is provided on the crystal base 121 in a plan view. The other extraction electrode 127b is electrically connected to the excitation electrodes 125a and 126a, and is provided on the front and back main surfaces near the boundary of the crystal base 121.

Further, as shown in FIG. 3, the excitation electrode 125b is provided on the front and back main surfaces of the second vibrating arm portion 122b of the second crystal vibrating portion 123b. Further, the excitation electrodes 126a are provided on both side surfaces of the second crystal vibrating portion 123b facing the second vibrating arm portion 122b. The other extraction electrode 127b is electrically connected to the excitation electrodes 125b and 126b, and is provided on the front and back main surfaces of the crystal base portion 121. The other lead-out electrode 127b is provided on the crystal base 121.

The weight portion 128 is provided in the shape of a hammer head at the end of the crystal vibrating portion 123 on the side opposite to the crystal base portion 121. The weight portion 128 is for adjusting the frequency of the bending vibration generated in the crystal vibrating portion 123. Specifically, by providing the weight portion 128, it is possible to approach the state in which the weight is provided on the tip side of the crystal vibrating portion 123, so that the frequency of the bending vibration generated in the crystal vibrating portion 123 is not set by the weight portion 128. It can be set to be lower than in the case, and the frequency of the bending vibration generated in the crystal vibrating unit 123 is adjusted to be a desired frequency. Further, the weight portion 128 is composed of a first weight portion 128a provided at the tip of the first crystal vibrating portion 123a and a second weight portion 128b provided at the tip of the second crystal vibrating portion 123b. Has been done.

The frequency adjusting electrode 129 is for adjusting the frequency of the bending vibration generated in the crystal vibrating unit 123 so as to be a desired frequency by cutting with a laser or the like. The frequency adjustment electrode 129 is composed of a first frequency adjustment electrode 129a and a second frequency adjustment electrode 129b. The first frequency adjusting electrode 129a is provided at the tip of the front main surface and the side surface of the first weight portion 128a, and the second frequency adjusting electrode 129b is provided at the tip of the front main surface and both side surfaces of the second weight portion 128b. It is provided.

The tuning fork type crystal element 120 can adjust the frequency value to a desired value by increasing or decreasing the amount of the metal constituting the frequency adjusting electrode 129. As shown in FIG. 3, the excitation electrodes 125b and 126b and the first frequency adjustment electrode 129a are electrically connected by a lead-out electrode 127b provided on the surface of the crystal piece. Further, the excitation electrodes 125a and 126a and the second frequency adjustment electrode 129b are electrically connected by a pull-out electrode 127a provided on the surface of the crystal base portion 121.

When the tuning fork type crystal element 120 is vibrated, an alternating voltage is applied to the extraction electrodes 127a and 127b. When a certain electrical state after application is momentarily captured, the excitation electrode 126b of the second crystal vibrating unit 123b has a + (plus) potential, the excitation electrode 126a has a- (minus) potential, and an electric field is generated from + to-. .. On the other hand, the excitation electrode 126 of the first crystal vibrating portion 123a at this time has a polarity opposite to the polarity generated in the excitation electrode 126 of the second crystal vibrating portion 123b. Due to these applied electric fields, a stretching phenomenon occurs in the first crystal vibrating section 123a and the second crystal vibrating section 123b, and bending vibration having a resonance frequency set in each crystal vibrating section 123 is obtained.

Taking the case where the long side dimension when the crystal piece is viewed in a plane is 0.8 to 1.2 mm and the short side dimension when the crystal piece is viewed in a plane is 0.2 to 0.7 mm as an example, the crystal base 121, The crystal vibration unit 123 will be described. The long side dimension of the crystal base 121 when viewed in a plan view is 0.2 to 0.4 mm, and the short side dimension when viewed in a plan view is 0.2 to 0.4 mm. The long side dimension of the crystal vibrating unit 123 when viewed in a plan view is 0.6 to 0.9 mm, and the short side dimension when viewed in a plan view is 0.03 to 0.2 mm.

Here, the operation of the tuning fork type crystal element 120 will be described. In the tuning fork type crystal element 120, when an alternating voltage from the outside is applied from the extraction electrode 127 to the crystal vibration unit 123 via the excitation electrodes 125 and 126, the crystal vibration unit 123 causes excitation in a predetermined vibration mode and frequency. It has become like.

Here, a method of manufacturing the tuning fork type crystal element 120 will be described. First, the tuning fork type crystal element 120 is cut from an artificial quartz body at a predetermined cut angle, and a crystal base portion 121, a crystal vibrating portion 123, and a crystal support portion 124 are formed on both main surfaces of the crystal piece by photolithography technology. Then, it is produced by forming the excitation electrodes 125 and 126 and the extraction electrode 127 by adhering a metal film by a photolithography technique, a vapor deposition technique or a sputtering technique.

Further, when viewed in a plan view, the length parallel to the X-axis in the crystal axis direction of the first recess K1 is set to be smaller than the length parallel to the X-axis in the crystal axis direction of the second recess K2. The length parallel to the X-axis in the crystal axis direction of the second recess K2 is set to be smaller than the length parallel to the X-axis in the crystal axis direction of the third recess K3. By doing so, the occupied area of the first frame body 110b becomes smaller from the first recess K1 toward the third recess K3, so that the stress applied to the package 110 is smaller than that of the third recess K3. Since the amount of strain displacement in the electrode pad 111 provided on the upper surface of the first frame 110b near K1 is small, it is possible to prevent the tuning fork type crystal element 120 from peeling off from the electrode pad 111.

A method of joining the tuning fork type 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 tuning fork type 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 mounted on the electrode pad 111.

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 terminals 151 is used, and a temperature sensor for detecting an ambient temperature state 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 sound fork type crystal element 120, and a temperature compensation circuit unit that corrects the vibration characteristics of the sound fork type crystal element 120 according to a temperature change based on the temperature compensation data. An oscillation circuit unit that is connected to the temperature compensation circuit unit to generate a predetermined oscillation output is provided. The output signal generated by the oscillation circuit unit is output to the outside of the piezoelectric oscillator via the second external terminal 112b, 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 third external terminal. It is input from the write / read terminal of 112c and saved. 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 tuning fork type 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 115 provided on the lower surface of the substrate 110a via a conductive bonding material 170 such as solder. Further, the connection terminal 151 of the integrated circuit element 150 is connected to the connection pad 115. The connection pad 115 is electrically connected to the external terminal 112. The first external terminal 112a 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.

A method of joining the integrated circuit element 150 to the substrate 110a will be described. First, the conductive bonding material 170 is applied to the connection pad 115 by, for example, a dispenser. The integrated circuit element 150 is placed on the conductive bonding material 170. Then, the conductive bonding material 170 is melt-bonded by heating. Therefore, the integrated circuit element 150 is joined to the connection pad 115.

Further, as shown in FIG. 1, 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 170 is made of, for example, silver paste or lead-free solder. Further, the conductive bonding material 170 contains an added solvent for adjusting the viscosity so that it can be easily applied. The lead-free solder component ratio is 95 to 97.5% for tin, 2 to 4% for silver, and 0.5 to 1.0% for copper.

As shown in FIG. 2, the insulating resin 180 is provided between the surface of the integrated circuit element 150 where the connection terminal 151 is provided and the connection pad 115. By doing so, the insulating resin 180 can increase the adhesive strength between the integrated circuit element 150 and the lower surface of the substrate 110a. Further, even if foreign matter such as solder gets into the fifth recess K5 when the crystal device is mounted on the mounting pad of the mounting board of an electronic device or the like, the foreign matter is accumulated by the insulating resin 180. Since it is possible to suppress adhesion between the connection terminals 151 of the 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 180 is made of an epoxy resin or a resin material such as a composite resin containing an epoxy resin as a main component.

Further, the insulating resin 180 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 tuning fork type crystal element 120. Therefore, it is possible to reduce fluctuations in the oscillation frequency of the tuning fork type crystal element 120.

A method of forming the insulating resin 180 on the substrate 110a will be described. After the contact pin is brought into contact with the measurement pad 118 and the characteristics of the tuning fork type crystal element 120 bonded to the substrate 210a are measured, the tip of the resin dispenser is inserted into the third frame 110d to form the insulating resin 180. Make an injection. Next, the insulating resin 180 is heated and cured. Therefore, the insulating resin 180 is provided between the integrated circuit element 150 and the connection pad 115.

The lid 130 is made of, for example, an alloy containing at least one of iron, nickel or cobalt. Such a lid 130 includes a first recess K1, a second recess K2, a third recess K3, a fourth recess K4, a first recess K1, a second recess K2, and a second recess K2 filled with nitrogen gas or the like in a vacuum state. The purpose is to airtightly seal the three recesses K3 and the fourth recess K4. Specifically, the lid body 130 is placed on the second frame body 110c of the package 110 in a predetermined atmosphere, and the sealing conductor pattern 117 of the second frame body 110c and the joining member 131 of the lid body 130 are formed. It is joined to the second frame body 110c by performing seam welding by applying a predetermined current so as to be welded. Further, the lid body 130 is electrically connected to the first external terminal 112a on the lower surface of the third frame body 110d via the sealing conductor pattern 117 and the third via conductor 114c.

The joining member 131 is provided at a position of the lid 130 facing the sealing conductor pattern 117 provided on the upper surface of the second frame 110c 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.

Here, a method of 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, the predetermined parts of the conductor pattern, specifically, the parts serving as the electrode pad 111, the external terminal 112, the wiring pattern 113, the via conductor 114, the sealing conductor pattern 117 and the measurement pad 118 are nickel-plated or gold-plated. It is produced by applying 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.

The crystal device according to the present embodiment includes a substrate 110a, a first frame body 110b provided along the outer peripheral edge of the upper surface of the substrate 110a, and a first frame body 110b provided along the outer peripheral edge of the upper surface of the first frame body 110b. A two-frame body 110c, a third frame body 110d provided along the outer peripheral edge of the lower surface of the substrate 110a, a pair of electrode pads 111 provided along the short side direction on the substrate 110a, and a rectangular crystal. The base portion 121, the crystal vibrating portion 123 extending from the side surface of the crystal base portion 121, the exciting electrodes 125 and 126 provided on the upper and lower surfaces of the crystal vibrating portion 123, and the exciting electrodes 125 and 126 were electrically connected. An electrode pad formed of a sound fork type crystal element 120 having a lead-out electrode 127, an integrated circuit element 150 mounted on a connection pad 115 provided on the lower surface of the substrate 110a, a substrate 110a, and a first frame 110b. The first recess K1 provided between the 111s, the second recess K2 formed by the substrate 110a and the first frame 110b and provided at a position facing the middle of the crystal vibrating portion 123, the substrate 110a and the first It is provided with a third recess K3 formed by the frame body 110b and provided at a position facing the tip of the crystal vibrating portion 123.

By doing so, when the tuning fork type crystal element 120 is mounted on the electrode pad 111, even if the tuning fork type crystal element 120 is tilted, the second recess K2 and the third recess K3 cause the vibrating arm portion 122. Can be suppressed from coming into contact with the upper surface of the substrate 110a, so that the crystal device can suppress fluctuations and stops of the oscillation frequency of the tuning fork type crystal element 120. Further, in the crystal device, even if the conductive adhesive 140 provided on the pair of adjacent electrode pads 111 is overflowed from the electrode pads 111 when the tuning fork type crystal element 120 is mounted by the first recess K1. By entering the first recess K1, it is possible to further prevent the adjacent electrode pads 111 from being short-circuited.

Further, the crystal device according to the present embodiment is provided so that the first recess K1, the second recess K2, and the third recess K3 are connected to each other. By doing so, even if the conductive adhesive 140 provided on the pair of adjacent electrode pads 111 overflows from the electrode pads 111 when the tuning fork type crystal element 120 is mounted, the first recess K1 It is possible to further prevent the adjacent electrode pads 111 from being short-circuited by entering the inside and flowing out from the first recess K1 through the second recess K2 to the third recess K3.

Further, the crystal device according to the present embodiment includes a measurement pad 118 electrically connected to an electrode pad 111 on the lower surface of the substrate 110a, and the measurement pad 118 is covered with an integrated circuit element 150. By doing so, it is possible to reduce the occurrence of stray capacitance between the mounting pattern provided on the upper surface of the mounting board of an electronic device or the like and the measurement pad 118, so that the tuning fork type crystal element 120 oscillates. It is possible to reduce the fluctuation of the frequency.

Further, the crystal device according to the present embodiment includes via conductors 114g and 114h that electrically connect the electrode pad 111 and the measurement pad 118, and a pair of crystal vibrations when the via conductors 114g and 114h are viewed in a plan view. It is provided so as to be located between the portions 123. By doing so, it is possible to suppress the generation of stray capacitance between the excitation electrodes 125 and 126 provided in the crystal vibrating portion 123 and the via conductors 114g and 114h, so that the tuning fork type crystal element 120 oscillates. It is possible to reduce frequency fluctuations.

Further, the crystal device according to the present embodiment includes an insulating resin 180 provided between the integrated circuit element 150 and the substrate 110a. By doing so, the insulating resin 180 can increase the adhesive strength between the integrated circuit element 150 and the lower surface of the substrate 110a. Further, even if foreign matter such as solder gets into the fifth recess K5 when the crystal device is mounted on the mounting pad of the mounting board of an electronic device or the like, the foreign matter is accumulated by the insulating resin 180. Since it is possible to suppress adhesion between the connection terminals 151 of the circuit element 150, it is possible to reduce a 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 second frame body 110c is integrally formed of the ceramic material like the substrate 110a and the first frame body 110b has been described, but the second frame body 110c may be made of metal. .. In this case, the frame is joined to the conductor film of the substrate via a brazing material such as silver-copper.

110 ... Package 110a ... Substrate 110b ... First frame 110c ... Second frame 110d ... Third frame 111 ... Electrode pad 112 ... External terminal 113 ... Wiring pattern 114: Via conductor 115: Connection pad 117: Encapsulating conductor pattern 118: Measuring pad 120: Sound fork type crystal element 121: Crystal base 122: Vibrating arm 123 ・ ・ ・ Crystal vibration part 125, 126 ・ ・ ・ Excitation electrode 127 ・ ・ ・ Pull-out electrode 128 ・ ・ ・ Weight part 129 ・ ・ ・ Frequency adjustment electrode 130 ・ ・ ・ Lid body 131 ・ ・ ・ Joint member 140 ・ ・ ・Conductive adhesive 150 ... Integrated circuit element 151 ... Connection terminal 170 ... Insulating bonding material 180 ... Insulating resin K1 ... First recess K2 ... Second recess K3 ... Third recess K4 ... Fourth recess K5 ... Fifth recess

Claims (3)

With the board
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 upper surface of the first frame, and
A third frame body provided along the outer peripheral edge of the lower surface of the substrate, and
A pair of electrode pads provided along the short side direction on the substrate, and
A rectangular crystal base, a crystal vibrating portion extending from the side surface of the crystal base, exciting electrodes provided on the upper and lower surfaces of the crystal vibrating portion, and an extraction electrode electrically connected to the exciting electrode. With a sound-forked crystal element having,
An integrated circuit element mounted on a connection pad provided on the lower surface of the substrate, and
A first recess formed between the substrate and the first frame and provided between the electrode pads,
A second recess formed by the substrate and the first frame and provided at a position facing the middle of the crystal vibrating portion,
It is provided with a third recess formed by the substrate and the first frame and provided at a position facing the tip of the crystal vibrating portion .
The first recess, the second recess, and the third recess are connected to each other.
The length of the first recess in the short side direction on the substrate is smaller than the length of the second recess in the short side direction on the substrate, and the length of the second recess in the short side direction on the substrate is smaller. , A crystal device characterized in that the length of the third recess on the substrate in the short side direction is smaller than that of the third recess . The crystal device according to claim 1.
A measurement pad electrically connected to the electrode pad is provided on the lower surface of the substrate.
A crystal device characterized in that the measuring pad is covered with the integrated circuit element. The crystal device according to claim 1.
A via conductor for electrically connecting the electrode pad and the measuring pad electrically connected to the electrode pad is provided.
A crystal device characterized in that the via conductor is provided so as to be located between a pair of the crystal vibrating portions when viewed in a plan view.