JP6892345B2 - Crystal device - Google Patents

Description

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

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

Japanese Unexamined Patent Publication No. 2009-89437

The crystal device described above is becoming smaller and smaller, and the area of the joining terminal of the container body and the joining pad of the mounting frame body becomes smaller, so that the joining strength between the container body and the mounting frame body may decrease. there were.

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 improving the joint strength between a container body and a mounting frame body.

The crystal device according to one aspect of the present invention has a rectangular substrate, a frame body provided along the outer peripheral edge of the upper surface of the substrate, and an opening, and a bonding pad is provided on the upper surface and an external terminal is provided on the lower surface. The mounting frame is joined to the lower surface of the board by joining the mounting terminal provided on the lower surface of the board and the joining pad, and the crystal element mounted on the electrode pad provided on the upper surface of the board and the opening. An integrated circuit element mounted on a connection pad provided on the lower surface of the substrate so as to be accommodated in the portion, and provided between the integrated circuit element and the lower surface of the substrate and between the upper surface of the mounting frame and the lower surface of the substrate. It is provided with an insulating resin, a lid bonded to the upper surface of the frame, and a notch provided from the joint pad of the mounting frame to the external terminal, and the insulating resin is provided on the upper end side of the notch. It is characterized in that it is provided.

The crystal device according to one aspect of the present invention has a rectangular substrate, a frame body provided along the outer peripheral edge of the upper surface of the substrate, and an opening, and a bonding pad is provided on the upper surface and an external terminal is provided on the lower surface. The mounting frame is joined to the lower surface of the board by joining the mounting terminal provided on the lower surface of the board and the joining pad, and the crystal element mounted on the electrode pad provided on the upper surface of the board and the opening. An integrated circuit element mounted on a connection pad provided on the lower surface of the substrate so as to be accommodated in the portion, and provided between the integrated circuit element and the lower surface of the substrate and between the upper surface of the mounting frame and the lower surface of the substrate. It is provided with an insulating resin, a lid bonded to the upper surface of the frame, and a notch provided from the joint pad of the mounting frame to the external terminal, and the insulating resin is provided on the upper end side of the notch. It is provided. By doing so, when the substrate and the mounting frame are joined, the conductive bonding material is joined so as to enter the notch portion, thereby improving the joining strength between the substrate and the mounting frame. It becomes possible to make it. Further, the insulating resin is provided between the integrated circuit element and the lower surface of the substrate, the upper surface of the mounting frame and the lower surface of the substrate, and is provided on the upper end side of the notch portion. By doing so, it is possible to reduce the fact that the mounting frame is peeled off from the lower surface of the substrate due to the insulating resin.

It is an exploded perspective view which shows the crystal device which concerns on this embodiment. (A) is a cross-sectional view taken along the line AA of FIG. 1, and FIG. 1B is a cross-sectional view taken along the line BB of FIG. (A) is a perspective view from the top surface of the package constituting the crystal device according to the present embodiment, and (b) is a perspective view from the top 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. (A) is a plan view seen from the upper surface of the mounting frame constituting the crystal device according to the present embodiment, and (b) is a plan view seen from the lower surface of the mounting frame constituting the crystal device according to the present embodiment. It is a figure. (A) is a plan view seen from the upper surface of the mounting frame constituting the crystal device according to the first modification of the present embodiment, and (b) is a plan view of the crystal device according to the first modification of the present embodiment. It is a top view seen from the lower surface of the mounting frame body which constitutes.

(Crystal Device) As shown in FIGS. 1 and 2, the crystal device in the present embodiment is bonded to the package 110, the crystal element 120 bonded to the upper surface of the package 110, and the lower surface of the package 110. It includes an integrated circuit element 150, which is one of the electronic components. The package 110 is formed with a first recess K1 surrounded by an upper surface of the substrate 110a and an inner side surface of the frame body 110b. Further, a second recess K2 surrounded by the lower surface of the substrate 110a and the inner surface of the mounting frame 160 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 115 for mounting the integrated circuit element 150 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 crystal element 120 are provided. Bonding terminals 112 are provided at the four corners of the lower surface of the substrate 110a. Further, a pair of measurement pads 119 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 119. Further, the joining terminals 112 are electrically connected to four on the outside of the connecting 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 119 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 pattern 116 for electrically connecting the connection pad 115 and the measurement pad 119 provided on the lower surface and the joining terminal 112 provided on the lower surface of the substrate 110a is provided. There is.

The 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 frame body 110b is made of 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. 3 and 4, the electrode pad 111 is electrically connected to the joining terminal 112 provided on the lower surface of the substrate 110a via the wiring pattern 113 and the via conductor 114 provided on the upper surface of the substrate 110a. It is connected to the.

As shown in FIG. 3, the electrode pad 111 is composed of a first electrode pad 111a and a second electrode pad 111b. The via conductor 114 is composed of a first via conductor 114a, a second via conductor 114b, and a third via conductor 114c. Further, the wiring pattern 113 is composed of the first wiring pattern 113a and the second wiring pattern 113b. The measurement pad 119 is composed of a first measurement pad 119a and a second measurement pad 119b. 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 second measurement pad 119b via the first via conductor 114a. Therefore, the first electrode pad 111a is electrically connected to the second measurement pad 119b. 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 first measurement pad 119a via the second via conductor 114b. Therefore, the second electrode pad 111b is electrically connected to the first measurement pad 119a. Further, the first measurement pad 119a is electrically connected to the fifth connection pad 115e via the fifth connection pattern 116e. Therefore, the first electrode pad 111a is electrically connected to the fifth connection pad 115e. Further, the second measurement pad 119b is electrically connected to the second connection pad 115b via the second connection pattern 116b. Therefore, the second electrode pad 111b is electrically connected to the second connection pad 115b.

The joining terminal 112 is used for electrically joining the joining pad 161 of the mounting frame 160. As shown in FIG. 4A, the bonding terminals 112 are provided at the four corners of the lower surface of the substrate 110a, and are composed of a first bonding terminal 112a, a second bonding terminal 112b, a third bonding terminal 112c, and a fourth bonding terminal 112d. Has been done. The joining terminal 112 is electrically connected to each of the connection pads 115 provided on the lower surface of the substrate 110a. Further, the second junction terminal 112b is electrically connected to the sealing conductor pattern 117 via the third via conductor 114c.

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 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 119. The via conductor 114 is provided by filling the inside of the through hole provided in the substrate 110a with a conductor. Further, the via conductor 114 is provided at a position overlapping the mounting frame 160 as shown in FIG. 4 in a plan view. By doing so, the crystal device of the present embodiment reduces the stray capacitance generated between the mounting pattern on the mounting substrate of an electronic device or the like and the via conductor 114, thereby causing the stray capacitance in the crystal element 120. Is not added, it is possible to reduce fluctuations in the oscillation frequency of the crystal element 120.

The connection pad 115 is used to mount the integrated circuit element 150. Further, as shown in FIG. 4, 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 and the first connection terminal 112a are connected by a first connection pattern 116a provided on the lower surface of the substrate 110a, and the second connection pad 115b and the second measurement pad 119b are connected to the substrate 110a. It is connected by a second connection pattern 116b provided on the lower surface. The third connection pad 115c and the fourth junction terminal 112d are connected by a third connection pattern 116c provided on the lower surface of the substrate 110a, and the fourth connection pad 115d and the third junction terminal 112c are connected to the substrate 110a. It is connected by a fourth connection pattern 116d provided on the lower surface. Further, the fifth connection pad 115e and the first measurement pad 119a are connected by a fifth connection pattern 116e provided on the lower surface of the substrate 110a, and the sixth connection pad 115f and the second joint terminal 112b are connected to the substrate. It is connected by a sixth connection pattern 116f provided on the lower surface of the 110a. Further, the connection pattern 116 is provided on the lower surface of the substrate 110a and is drawn out from the connection pad 115 toward the nearby joining terminal 112 or the measurement pad 119.

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. 3 and 4, the sealing conductor pattern 117 is electrically connected to the third junction terminal 112c via the third via conductor 114c. The sealing conductor pattern 117 is formed to have 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 frame 110b. Has been done.

The measuring pad 119 is for measuring the characteristics of the crystal element 120 by bringing the contact pin or the like into contact with the measuring pad 119. The measurement pad 119 is composed of a first measurement pad 119a and a second measurement pad 119b. The measurement pad 119 is electrically connected to the electrode pad 111 provided on the upper surface of the substrate 110a via the wiring pattern 113 and the via conductor 114 provided on the substrate 110a. The first measurement pad 119a is electrically connected to the fifth connection pad 115e via the fifth connection pattern 116e. Further, the second measurement pad 119b is electrically connected to the second connection pad 115b via the second connection pattern 116b. The measurement pad 119 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 the electronic device or the like and the measurement pad 119 is reduced, so that the stray capacitance is not added to the crystal element 120. It is possible to reduce fluctuations in the oscillation frequency.

Here, the size of the measurement pad 119 will be described by taking as an example the case where the dimension of one side when the package 110 is viewed in a plan view is 1.0 to 2.0 mm. The length of the long side of the measuring pad 119 is 0.5 to 0.8 mm, and the length of the short side is 0.45 to 0.75 mm. Further, since the measurement of the crystal element 120 is performed before mounting the mounting frame 160, the area of the measurement pad 119 can be increased as compared with the conventional crystal device. Since the area of the measurement pad 119 can be increased, poor contact between the contact pin and the measurement pad 119 can be reduced. Therefore, it is possible to suppress the remeasurement of the crystal element 120 caused by the poor contact between the contact pin and the measurement pad 119, and it is possible to improve the productivity of the piezoelectric oscillator.

The electrical characteristic measuring instrument used when measuring the characteristics of the crystal element 120 is a network analyzer or a network analyzer capable of measuring equivalent parameters such as inductance and capacitance in addition to the resonance frequency and crystal impedance of the crystal element 120. 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, a predetermined portion of the conductor pattern, specifically, an electrode pad 111, a joining terminal 112, a wiring pattern 113, a via conductor 114, a connection pad 115, a connection pattern 116, a sealing conductor pattern 117, and a measurement pad 119. It is produced by subjecting the site 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.

The mounting frame 160 is joined to the lower surface of the substrate 110a to form a second recess K2 on the lower surface of the substrate 110a. The outer shape of the mounting frame 160 is provided so as to be larger than the outer shape of the substrate 110a in a plan view. The mounting frame 160 is made of an insulating substrate such as glass epoxy resin, and is bonded to the lower surface of the substrate 110a via a conductive bonding material 170. Inside the mounting frame 160, a conductor portion 163 for electrically connecting the joining pad 161 provided on the upper surface and the external terminal 162 provided on the lower surface of the mounting frame 160 is provided. Bonding pads 161 are provided at the four corners of the upper surface of the mounting frame 160, and external terminals 162 are provided at the four corners of the lower surface. Further, the external terminal 162 is electrically connected to the integrated circuit element 150.

The bonding pad 161 is for electrically bonding to the bonding terminal 112 of the substrate 110a via the conductive bonding material 170. As shown in FIG. 5, the joining pad 161 is composed of a first joining pad 161a, a second joining pad 161b, a third joining pad 161c, and a fourth joining pad 161d. Further, as shown in FIG. 5, the external terminal 162 is composed of a first external terminal 162a, a second external terminal 162b, a third external terminal 162c, and a fourth external terminal 162d. The conductor portion 163 is composed of a first conductor portion 163a, a second conductor portion 163b, a third conductor portion 163c, and a fourth conductor portion 163d. The first joint pad 161a is electrically connected to the first external terminal 162a via the first conductor portion 163a, and the second joint pad 161b is connected to the second external terminal 162b via the second conductor portion 163b. It is electrically connected. The third joint pad 161c is electrically connected to the third external terminal 162c via the third conductor portion 163c, and the fourth joint pad 161d is connected to the fourth external terminal 162d via the fourth conductor portion 163d. It is electrically connected.

The external terminal 162 is for mounting on a mounting board of an electronic device or the like. The external terminals 162 are provided at the four corners of the lower surface of the mounting frame 160. The external terminals 162 are electrically connected to four of the six connection pads 115 provided on the lower surface of the substrate 110a. Further, the second external terminal 162b 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 second external terminal 162b, 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 162a is used as an output terminal, the third external terminal 162c is used as a functional terminal, and the fourth external terminal 162d is used as a power supply voltage terminal. The functional terminal is used as a write / read terminal and a frequency control terminal. 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 characteristic of the crystal element 120 by changing the load capacitance of the variable capacitance diode of the oscillation circuit unit when a voltage is applied.

The conductor portion 163 is for electrically connecting the bonding pad 161 on the upper surface of the substrate 110a and the external terminal 162 on the lower surface. The conductor portion 163 is formed by providing through holes at the four corners of the mounting frame 160, forming conductive members on the inner wall surface of the through holes, closing the upper surface thereof with a joining pad 161 and closing the lower surface thereof with an external terminal 162. ing. Further, by providing the conductor portions 163 provided at the four corners of the mounting frame 160, the crystal device is a conductor for electrically connecting the bonding pad 161 on the upper surface of the substrate 110a and the external terminal 162 on the lower surface. Since it is performed at two locations, the portion 163 and the notch portion 164, it is possible to reduce the conduction failure.

The cutout portion 164 is for electrically connecting the bonding pad 161 on the upper surface of the substrate 110a and the external terminal 162 on the lower surface, and for improving the bonding strength between the substrate 110a and the mounting frame 160. The cutout portion 164 is provided along the long side of the mounting frame 160 so as to penetrate in a semi-cylindrical manner from the joining pad 161 to the external terminal 162 in the vertical direction, and a conductive member is formed on the surface thereof. There is. When the substrate 110a and the mounting frame 160 are joined to each other, the notch portion 164 is formed by joining the conductive bonding material 170, which will be described later, so as to enter the notch portion 164. And the mounting frame body 160 can be improved in joint strength. Further, an insulating resin 180, which will be described later, is provided between the integrated circuit element 150, the lower surface of the substrate 110a, the upper surface of the mounting frame 160, and the lower surface of the substrate 110a, and is provided on the upper end side of the notch portion 164. There is. By doing so, it is possible to reduce that the mounting frame 160 is peeled off from the lower surface of the substrate 110a due to the insulating resin 180.

The protective member 165 is for reducing short-circuiting of adjacent joining pads when the conductive joining member 170 overflows. The protective member 165 is made of a thermosetting resin (for example, an epoxy resin) containing a pigment or the like. The protective member 165 is provided on the upper surface of the mounting frame 160 between the adjacent joint pads 161 while exposing the plurality of joint pads 161. The protective member 165 is formed thicker than the joining pad 161 and the external terminal 162. For example, the thickness of the bonding pad 161 and the external terminal 162 is 15 μm or more and 40 μm or less, whereas the thickness of the protective member 165 is 10 μm or more and 25 μm or more and 100 μm or less. In this way, while exposing the plurality of bonding pads 161 and being provided on the upper surface of the mounting frame 160 between the adjacent bonding pads 161 so that the conductive bonding material 170 overflows, the bonding pads 161 Since the conductive bonding material 170 is blocked by the step between the protective member 165 and the protective member 165, it is possible to reduce short-circuiting of adjacent bonding pads 161.

As shown in FIG. 5, the protective member 165 is provided on the joining pad 161 so as to surround the notch portion 164. By doing so, it is possible to prevent the conductive bonding material 170 applied to the bonding pad 161 of the mounting frame 160 from flowing out to the external terminal 161 through the notch portion 164. Therefore, it is possible to maintain the joint strength between the substrate 110a and the mounting frame 160.

The shape of the opening of the second recess K2 is rectangular in a plan view. Here, taking the case where the dimension of the long side when the substrate 110a is viewed in a plan view is 1.2 to 2.5 mm and the dimension of the short side is 1.0 to 2.0 mm as an example, the second concave portion The size of the opening of K2 will be described. The length of the long side of the second recess K2 is 0.8 to 1.5 mm, and the length of the short side is 0.5 to 1.2 mm.

A method of joining the mounting frame 160 to the substrate 110a will be described. First, the conductive bonding material 170 is applied onto the first bonding pad 161a, the second bonding pad 161b, the third bonding pad 161c, and the fourth bonding pad 161d by, for example, a dispenser and screen printing. The substrate 110a is conveyed so that the bonding terminal 112 of the substrate 110a is located on the conductive bonding material 170, and is placed on the conductive bonding material 170. Then, the conductive bonding material 170 is cured and shrunk by being heat-cured. As a result, the joining terminal 112 of the substrate 110a is joined to the joining pad 161. That is, the first bonding terminal 112a of the substrate 110a is bonded to the first bonding pad 161a, and the second bonding terminal 112b of the substrate 110a is bonded to the second bonding pad 161b. Further, the third bonding terminal 112c of the substrate 110a is bonded to the third bonding pad 161c, and the fourth bonding terminal 112d of the substrate 110a is bonded to the fourth bonding pad 161d.

Further, as shown in FIG. 2B, the bonding terminal 112 of the substrate 110a and the bonding pad 161 of the mounting frame 160 are bonded via the conductive bonding material 170, so that the substrate 110a and the mounting frame 160 are bonded. A gap H is provided between the two, which is the sum of the thickness of the conductive bonding material 170 and the thickness of the bonding terminal 112 and the bonding pad 161. By filling the gap H with the insulating resin 180, the bonding strength between the substrate 110a and the mounting frame 160 can be improved. Further, the outer shape of the mounting frame 160 is provided so as to be larger than the outer shape of the substrate 110a in a plan view, and the insulating resin 180 is provided from the outer peripheral edge of the lower surface of the substrate 110a to the mounting frame 160. An inclination is provided so that the thickness in the vertical direction becomes thinner toward the upper surface of the. By doing so, even when the overall structure of the crystal device is miniaturized, it is possible to secure a wide adhesion area of the insulating resin 180 on the substrate 110a, whereby the mounting frame 160 can be secured. Can be firmly bonded to the substrate 110a.

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 base 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 first lead-out electrode 123a of the crystal element 120 is joined to the second electrode pad 111b, and the second pull-out electrode 123b is joined to the first electrode pad 111a. As a result, the second connection pad 115b and the fifth connection pad 115e are electrically connected to the crystal element 120 via the first measurement pad 119a and the second measurement pad 119b.

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 is provided which is connected to and generates a predetermined oscillation output. The output signal generated by the oscillation circuit unit is output to the outside of the piezoelectric oscillator via the first external terminal 162a of the mounting frame 160, and is used as a reference signal such as a clock signal.

The storage element unit is composed of PROM and 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 functional terminal of 162c and saved. A register map is stored in the storage element unit. The register map shows how the control unit reads the data, outputs a signal, and performs an operation 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 inside 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. 2B, 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 joining terminal 112 via a connection pattern 116. The joining terminal 112 is electrically connected to the joining pad 161 via a conductive joining member 170. The joining pad 161 is electrically connected to the external terminal 162 via the conductor portion 163 and the notch portion 164. Therefore, the connection pad 115 is electrically connected to the external terminal 162 via the joint terminal 112. The second external terminal 162b 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 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 170 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 lead-free solder has a component ratio of 95 to 97.5% for tin, 2 to 4% for silver, and 0.5 to 1.0% for copper.

As shown in FIG. 2A, 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 second recess K2 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 119. By doing so, it is possible to prevent foreign matter from adhering to the measurement pad 119, 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.

As shown in FIG. 2, the insulating resin 180 is provided in the gap H provided between the lower surface of the substrate 110a and the upper surface of the mounting frame 160. By doing so, the insulating resin 180 can improve the bonding strength between the lower surface of the substrate 110a and the upper surface of the mounting frame 160. Further, the insulating resin 180 is provided on the lower surface of the via conductor 114, and the outer peripheral edge of the lower surface of the via conductor 114 is fixed to the substrate 110a by the insulating resin 180. By doing so, even if the substrate 110a is warped or the like, since the via conductor is fixed by the insulating resin 180, the via conductor 114 is formed from the interface between the outer peripheral edge of the via conductor 114 and the substrate 110a. Can be reduced from peeling off. Further, by reducing the peeling of the via conductor 114 from the interface between the outer peripheral edge of the via conductor 114 and the substrate 110a, there is no gap at the interface between the via conductor 114 and the substrate 110a, and the substrate 110a is airtight. The sex can be improved.

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 119 and the characteristics of the crystal element 120 bonded to the substrate 110a are measured, the tip of the resin dispenser is inserted into the gap of the second recess K2 to inject the insulating resin 180. Do. Next, the insulating resin 180 is heated and cured. Therefore, the insulating resin 180 is provided in the gap H provided between the lower surface of the substrate 110a and the upper surface of the mounting frame 160, and 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 is for airtightly sealing the first recess K1 in a vacuum state or the first recess K1 filled with nitrogen gas or the like. Specifically, the lid body 130 is placed on the frame body 110b of the package 110 in a predetermined atmosphere, and the sealing conductor pattern 117 of the frame body 110b and the joining member 131 of the lid body 130 are welded to each other. By applying a predetermined current to the seam welding, the frame body 110b is joined. Further, the lid body 130 is electrically connected to the second bonding terminal 112b on the lower surface of the substrate 110a via the sealing conductor pattern 117 and the third via conductor 114c. The second bonding terminal 112b is electrically connected to the second bonding pad 161b via the conductive bonding material 170. The second bonding pad 161b is electrically connected to the second external terminal 162b via the second conductor portion 163b. Therefore, the lid body 130 is electrically connected to the second external terminal 162b of the mounting frame body 160.

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 frame 110b of the package 110. The joining member 131 is provided with, for example, silver brazing or gold tin. In the case of silver wax, its thickness is 10 to 20 μm. For example, the component ratio is 72 to 85% for silver and 15 to 28% for copper. 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 of the present embodiment has a rectangular substrate 110a, a frame body 110b provided along the outer peripheral edge of the upper surface of the substrate 110a, and an opening, and has a bonding pad 161 on the upper surface and an external terminal 162 on the lower surface. Is provided, and the mounting frame body joined to the lower surface of the substrate 110a by joining the mounting terminal 112 provided on the lower surface of the substrate 110a and the joining pad 161 and the electrode pad 111 provided on the upper surface of the substrate 110a. The mounted crystal element 120, the integrated circuit element 150 mounted on the connection pad 115 provided on the lower surface of the substrate 110a so as to be accommodated in the opening, and the lower surface and mounting of the integrated circuit element 150 and the substrate 110a. The insulating resin 180 provided between the upper surface of the frame 161 and the lower surface of the substrate 110a, the lid 130 bonded to the upper surface of the frame 110b, and the bonding pad 161 of the mounting frame 160 to the external terminal 162. The notch portion 164 is provided, and the insulating resin 180 is provided on the upper end side of the notch portion 164. Such a crystal device is mounted on the substrate 110a by joining the conductive bonding material 170, which will be described later, so as to enter the notch portion 164 when the substrate 110a and the mounting frame 160 are bonded. It is possible to improve the joint strength with the frame body 160. Further, an insulating resin 180, which will be described later, is provided between the integrated circuit element 150, the lower surface of the substrate 110a, the upper surface of the mounting frame 160, and the lower surface of the substrate 110a, and is provided on the upper end side of the notch portion 164. There is. By doing so, it is possible to reduce that the mounting frame 160 is peeled off from the lower surface of the substrate 110a due to the insulating resin 180.

Further, the crystal device of the present embodiment includes a protective member 165 provided between the joining pads 161 on the upper surface of the mounting frame 160. In such a crystal device, when the conductive bonding material 170 overflows, the conductive bonding material 170 is blocked by the step between the bonding pad 161 and the protective member 165, so that the adjacent bonding pads 161 are less likely to be short-circuited. can do.

Further, in the crystal device of the present embodiment, the protective member 165 is provided on the joining pad 161 so as to surround the notch portion 164. In such a crystal device, by doing so, it is possible to prevent the conductive bonding material 170 applied to the bonding pad 161 of the mounting frame 160 from flowing out to the external terminal 161 through the notch 164. Can be done. Therefore, it is possible to maintain the joint strength between the substrate 110a and the mounting frame 160.

Further, the crystal device of the present embodiment includes conductor portions 163 provided at the four corners of the mounting frame 160. In such a crystal device, in order to electrically connect the bonding pad 161 on the upper surface of the substrate 110a and the external terminal 162 on the lower surface, the conductor portion 163 and the notch portion 164 are used at two locations, resulting in poor continuity. Can be reduced.

(First modification)
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. As shown in FIG. 6, the crystal device in the first modification of the present embodiment is present in that the notch 264 provided in the mounting frame 260 is provided along the short side of the mounting frame 260. Different from the embodiment.

The mounting frame 260 is joined to the lower surface of the substrate 110a to form a second recess K2 on the lower surface of the substrate 110a. The outer shape of the mounting frame 260 is provided so as to be larger than the outer shape of the substrate 110a in a plan view. The mounting frame 260 is made of an insulating substrate such as glass epoxy resin, and is bonded to the lower surface of the substrate 110a via a conductive bonding material 170. Inside the mounting frame 260, a conductor portion 263 for electrically connecting the joining pad 261 provided on the upper surface and the external terminal 262 provided on the lower surface of the mounting frame 260 is provided. Bonding pads 261 are provided at the four corners of the upper surface of the mounting frame 260, and external terminals 262 are provided at the four corners of the lower surface. Further, the external terminal 262 is electrically connected to the integrated circuit element 150.

The bonding pad 261 is for electrically bonding to the bonding terminal 112 of the substrate 110a via the conductive bonding material 170. As shown in FIG. 6, the joining pad 261 is composed of a first joining pad 261a, a second joining pad 261b, a third joining pad 261c, and a fourth joining pad 261d. Further, as shown in the figure, the external terminal 262 is composed of a first external terminal 262a, a second external terminal 262b, a third external terminal 262c, and a fourth external terminal 262d. The conductor portion 263 is composed of a first conductor portion 263a, a second conductor portion 263b, a third conductor portion 263c, and a fourth conductor portion 263d. The first joint pad 261a is electrically connected to the first external terminal 162a via the first conductor portion 263a, and the second joint pad 261b is connected to the second external terminal 262b via the second conductor portion 263b. It is electrically connected. The third joint pad 261c is electrically connected to the third external terminal 262c via the third conductor portion 263c, and the fourth joint pad 261d is connected to the fourth external terminal 262d via the fourth conductor portion 263d. It is electrically connected.

The external terminal 262 is for mounting on a mounting board of an electronic device or the like. The external terminals 162 are provided at the four corners of the lower surface of the mounting frame 160. The external terminals 262 are electrically connected to four of the six connection pads 215 provided on the lower surface of the substrate 210a. Further, the second external terminal 262b 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 second external terminal 262b, 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 262a is used as an output terminal, the third external terminal 262c is used as a functional terminal, and the fourth external terminal 262d is used as a power supply voltage terminal. The functional terminal is used as a write / read terminal and a frequency control terminal. 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 characteristic of the crystal element 120 by changing the load capacitance of the variable capacitance diode of the oscillation circuit unit when a voltage is applied.

The conductor portion 263 is for electrically connecting the bonding pad 261 on the upper surface of the substrate 110a and the external terminal 262 on the lower surface. The conductor portion 263 is formed by providing through holes at the four corners of the mounting frame 260, forming conductive members on the inner wall surface of the through holes, closing the upper surface thereof with a joining pad 261 and closing the lower surface thereof with an external terminal 262. ing.

The cutout portion 264 is for electrically connecting the bonding pad 261 on the upper surface of the substrate 110a and the external terminal 262 on the lower surface, and for improving the bonding strength between the substrate 110a and the mounting frame 260. The cutout portion 264 is provided along the short side of the mounting frame 260 so as to penetrate vertically from the joining pad 261 to the external terminal 262 in a semicircular shape, and a conductive member is formed on the surface thereof. There is. When the substrate 110a and the mounting frame 260 are joined to each other, the notch portion 264 is joined so that the conductive bonding material 170, which will be described later, enters the notch portion 264, thereby joining the substrate 110a. It is possible to improve the joint strength between the and the mounting frame 260. Further, the insulating resin 180 described later is provided between the integrated circuit element 150 and the lower surface of the substrate 110a and the upper surface of the mounting frame 260 and the lower surface of the substrate 110a, and is provided on the upper end side of the notch portion 264. There is. By doing so, it is possible to reduce that the mounting frame 260 is peeled off from the lower surface of the substrate 110a due to the insulating resin 180.

The protective member 265 is for reducing short-circuiting of adjacent joining pads 261 when the conductive joining member 170 overflows. The protective member 265 is made of a thermosetting resin (for example, an epoxy resin) containing a pigment or the like. The protective member 265 is provided on the upper surface of the mounting frame 260 between the adjacent joint pads 261 while exposing the plurality of joint pads 261. The protective member 265 is formed thicker than the joining pad 261 and the external terminal 262. For example, the thickness of the bonding pad 261 and the external terminal 262 is 15 μm or more and 40 μm or less, whereas the thickness of the protective member 265 is 10 μm or more and 25 μm or more and 100 μm or less. In this way, while exposing the plurality of bonding pads 261 and being provided on the upper surface of the mounting frame 260 between the adjacent bonding pads 261, the bonding pads 261 when the conductive bonding material 170 overflows. Since the conductive bonding material 170 is blocked by the step between the protective member 265 and the protective member 265, it is possible to reduce short-circuiting of adjacent bonding pads 261.

The protective member 265 is provided on the joint pad 261 so as to surround the notch 264. By doing so, it is possible to prevent the conductive bonding material 170 applied to the bonding pad 261 of the mounting frame 260 from flowing out to the external terminal 261 through the notch 264. Therefore, it is possible to maintain the joint strength between the substrate 110a and the mounting frame 260.

The shape of the opening of the second recess K2 is rectangular in a plan view. Here, taking the case where the dimension of the long side when the substrate 110a is viewed in a plan view is 1.2 to 2.5 mm and the dimension of the short side is 1.0 to 2.0 mm as an example, the second concave portion The size of the opening of K2 will be described. The length of the long side of the second recess K2 is 0.8 to 1.5 mm, and the length of the short side is 0.5 to 1.2 mm.

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 frame body 110b is integrally formed of the ceramic material like the substrate 110a has been described, but the frame body 110b 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.

Further, in the above embodiment, the case where the conductor portion 163 is provided in the substrate has been described, but the conductor portion 163 may be provided inside the notch provided in the corner portion of the mounting frame body 160. At this time, the conductive portion is provided so as to print the conductor paste in the notch.

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 ・ ・ ・ Board 110b ・ ・ ・ Frame 111 ・ ・ ・ Electrode pad 112 ・ ・ ・ Joint terminal 113 ・ ・ ・ Wiring pattern 114 ・ ・ ・ Via conductor 115 ・ ・ ・ Connection pad 116 ・ ・ ・Connection pattern 117 ・ ・ ・ Conductor pattern for sealing 119 ・ ・ ・ Measurement pad 120 ・ ・ ・ Crystal element 121 ・ ・ ・ Crystal base plate 122 ・ ・ ・ Excitation electrode 123 ・ ・ ・ Pull-out electrode 130 ・ ・ ・ Lid body 131・ ・ ・ Joint member 140 ・ ・ ・ Conductive adhesive 150 ・ ・ ・ Integrated circuit element 151 ・ ・ ・ Connection terminal 160 ・ ・ ・ Mounting frame 161 ・ ・ ・ Joint pad 162 ・ ・ ・ External terminal 163 ・ ・ ・ Conductor Part 164: Notch 170: Insulating bonding material 180: Insulating resin K1: First recess K2: Second recess (opening)
H ... Gap

Claims (4)

With a rectangular board
A frame provided along the outer peripheral edge of the upper surface of the substrate and
With an opening, a joining pad is provided on the upper surface and an external terminal is provided on the lower surface, and a mounting frame body joined to the lower surface of the substrate by joining the mounting terminal provided on the lower surface of the substrate and the joining pad. ,
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 so as to be housed in the opening.
Insulating resin provided between the integrated circuit element and the lower surface of the substrate, and between the upper surface of the mounting frame and the lower surface of the substrate,
A lid joined to the upper surface of the frame and
A notch provided from the joint pad of the mounting frame to the external terminal, and
With
The notch is provided on the outer peripheral side surface of the mounting frame.
A crystal device characterized in that the insulating resin is provided on the upper end side of the notch portion. The crystal device according to claim 1.
A crystal device including a protective member provided between the joining pads on the upper surface of the mounting frame. The crystal device according to claim 2.
A crystal device characterized in that the protective member is provided on the joint pad so as to surround the notch. The crystal device according to claim 1.
A crystal device including conductor portions provided at four corners of the mounting frame.

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