JP2017050578A - Crystal device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a crystal device capable of relaxing a stress to be applied to a crystal element and reducing fluctuation in an oscillation frequency of the crystal element.SOLUTION: A crystal device comprises: a rectangular substrate 110a; a first electrode pad 111 provided on the substrate 110a; a second electrode pad 112 provided along one side of the first electrode pad 111 in a center direction of the substrate 110a; a first bump 116 provided along one side of the first electrode pad 111; a second bump 117 provided along one side of the second electrode pad 112; and a crystal element 120 including excitation electrodes 122 provided on top and bottom faces of a crystal blank 121 and extraction electrodes 123 provided while being spaced apart from the excitation electrodes 122. The extraction electrode 123 is disposed at a position overlapped with the first bump 116 and the second bump 117 in a planar view, and connected with the first electrode pad 111 and the second electrode pad 112 via a conductive adhesive 140.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a crystal device used in, for example, an electronic apparatus.

  A quartz crystal device uses a piezoelectric effect of a quartz crystal element to cause a thickness-shear vibration so that both surfaces of a quartz base plate are shifted from each other, thereby generating a specific frequency. A crystal device including a crystal element mounted on an electrode pad provided on a substrate via a conductive adhesive has been proposed (for example, see Patent Document 1 below). The crystal element has excitation electrodes on both main surfaces of the crystal base plate, one end of the crystal element is a fixed end connected to the upper surface of the substrate, and the other end is a free end spaced from the upper surface of the substrate. This is a piece holding structure.

JP 2002-111435 A

  The above-described quartz device is remarkably miniaturized, but the quartz element mounted on the substrate is also downsized. When a conductive adhesive is applied on a conventional electrode pad and the crystal element is placed on the upper surface of the conductive adhesive, the free end of the crystal element or the excitation electrode comes into contact with the substrate, and the vibration is hindered. There was a possibility that the oscillation frequency of the element would 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 reducing fluctuations in the oscillation frequency of a crystal element.

  A quartz crystal device according to an aspect of the present invention has a rectangular substrate and a rectangular shape in plan view, a pair of first electrode pads provided on one side of the substrate along one side of the substrate, and a rectangular shape in plan view. A pair of second electrode pads provided along one side facing the center direction of the substrate of the first electrode pad, a pair of first bumps provided along one side of the first electrode pad, and a second electrode pad A pair of second bumps provided along one side of the substrate, a crystal base plate provided on the substrate, an excitation electrode provided on the upper and lower surfaces of the crystal base plate, and an excitation electrode on the lower surface of the crystal base plate A crystal element having a pair of lead electrodes provided apart from each other, and the lead electrodes are arranged at positions overlapping the first bump and the second bump in a plan view, and are electrically conductively bonded. Characterized in that it is connected to the electrode pad via an agent A.

  A quartz crystal device according to an aspect of the present invention has a rectangular substrate and a rectangular shape in plan view, a pair of first electrode pads provided on one side of the substrate along one side of the substrate, and a rectangular shape in plan view. A pair of second electrode pads provided along one side facing the center direction of the substrate of the first electrode pad, a pair of first bumps provided along one side of the first electrode pad, and a second electrode pad A pair of second bumps provided along one side of the substrate, a crystal base plate provided on the substrate, an excitation electrode provided on the upper and lower surfaces of the crystal base plate, and an excitation electrode on the lower surface of the crystal base plate A crystal element having a pair of lead electrodes provided apart from each other, and the lead electrodes are arranged at positions overlapping the first bump and the second bump in a plan view, and are electrically conductively bonded. It is connected to the electrode pad through the agent. By doing so, the crystal device reduces the contact of the tip of the crystal element and the excitation electrode with the substrate, and the thickness shear vibration of the crystal element is not hindered. Can be output.

It is a disassembled perspective view which shows the crystal device in this embodiment. (A) It is sectional drawing in AA of the crystal device shown by FIG. (B) It is the X partial enlarged view of the crystal device shown by Fig.2 (a). (A) It is a top view which shows the state which removed the cover of the crystal device in this embodiment, (b) It is a top view which shows the state which removed the cover and crystal element of the crystal device in this embodiment. (A) It is the top view which looked at the package which comprises the crystal device in this embodiment from the top, (b) It is a bottom view of the package which comprises the crystal device in this embodiment. (A) It is a top view which shows the state which removed the cover body of the crystal device in the 1st modification of this embodiment. (B) It is a top view which shows the state which removed the cover body and crystal element of the crystal device in the 1st modification of this embodiment.

  As shown in FIGS. 1 to 3, the crystal device according to the present embodiment is packaged so that the package 110, the crystal element 120 mounted on the substrate 110 a of the package 110, and the crystal element 120 are hermetically sealed. 110 and a lid 130 joined to 110. The package 110 has a recess K surrounded by the upper surface of the substrate 110a and the inner surface of the frame 110b.

  The substrate 110a has a rectangular shape and functions as a mounting member for mounting the crystal element 120 mounted on the upper surface. A pair of electrode pads 111 for bonding the crystal element 120 are provided on the upper surface of the substrate 110a. The substrate 110a is made of an insulating layer made of a ceramic material such as alumina ceramic or glass-ceramic. The substrate 110a may be one using an insulating layer or may be a laminate of a plurality of insulating layers. A wiring pattern 114 for electrically connecting the first electrode pad 111 and the second electrode pad 112 provided on the upper surface to the external terminal 113 provided on the lower surface of the substrate 110a is provided on and inside the substrate 110a. And via conductors 115 are provided.

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

  Here, when the package 110 is viewed in plan, the dimension of one side is 1.0 to 3.0 mm, and the dimension of the package 110 in the vertical direction is 0.2 to 1.5 mm. The size of K will be described. The length of the long side of the recess K is 0.7 to 2.0. mm, and the length of the short side is 0.5 to 1.5 mm. Moreover, the length of the up-down direction of the recessed part K is 0.1-0.5 mm.

  In addition, external terminals 113 are provided at the four corners of the lower surface of the substrate 110a. Two of the external terminals 113 are electrically connected to the first electrode pad 111 and the second electrode pad 112 provided on the upper surface of the substrate 110a. In addition, the external terminals 113 that are electrically connected to the first electrode pads 111 and the second electrode pads 112 are provided to be located diagonally on the lower surface of the substrate 110a.

  The first electrode pad 111 is for mounting the crystal element 120. The first electrode pads 111 are provided as a pair on the upper surface of the substrate 110a, and are provided adjacent to each other along one side of the substrate 110a. The first electrode pad 111 includes one first electrode pad 111a and the other first electrode pad 111b. The first electrode pad 111 is electrically connected to an external terminal 113 provided on the lower surface of the substrate 110a via a wiring pattern 114 and a via conductor 115 provided on the substrate 110a.

  The second electrode pad 112 is for mounting the crystal element 120. The second electrode pads 111 are provided as a pair on the upper surface of the substrate 110 a, and are provided adjacent to each other along one side of the first electrode pad 111. The second electrode pad 112 includes one second electrode pad 112a and the other second electrode pad 112b. The first electrode pad 111 is electrically connected to an external terminal 113 provided on the lower surface of the substrate 110a via a wiring pattern 114 and a via conductor 115 provided on the substrate 110a.

  The external terminal 113 is used for bonding to a mounting pad (not shown) on an external mounting board such as an electric device. The external terminals 113 are provided at the four corners of the lower surface of the substrate 110a. At least one of the external terminals 113 is electrically connected to the sealing conductor pattern 118 via the third via conductor 115c. In addition, at least one of the external terminals 113 is connected to a mounting pad connected to a ground potential that is a reference potential on a mounting substrate such as an electronic device. As a result, the lid body 130 bonded to the sealing conductor pattern 118 is connected to the third external terminal 113c having the ground potential. Therefore, the shielding performance in the recess K by the lid 130 is improved.

  The wiring pattern 114 is for electrically connecting the first electrode pad 111 and the second electrode pad 112 to the via conductor 115. One end of the wiring pattern 114 is electrically connected to the first electrode pad 111 and the second electrode pad 112, and the other end of the wiring pattern 114 is electrically connected to the via conductor 115. The wiring pattern 114 includes a first wiring pattern 114a and a second wiring pattern 114b.

  Further, the wiring pattern 114 is provided so as to overlap the frame 110b in plan view. By doing so, the crystal device suppresses the generation of stray capacitance between the wiring pattern 114 and the crystal element 120 even if the crystal elements 120 having different sizes are mounted. Since this stray capacitance is not applied, fluctuations in the oscillation frequency can be suppressed. Further, even when an external force is applied to the crystal device and a bending moment is generated in the long side direction of the frame 110b, the frame 110b is provided in addition to the substrate 110a, so that the frame 110b is provided. Becomes difficult to deform. Therefore, the wiring pattern 113 provided at a position overlapping the frame 110b in plan view is less likely to be disconnected, and the oscillation frequency is not output.

  The first wiring pattern 114a is electrically connected to one first electrode pad 111a, one second electrode pad 112a, and the first via conductor 115a. The first via conductor 115a is electrically connected to the first external terminal 113a. Therefore, one first electrode pad 111a and one second electrode pad 112a are electrically connected to the first external terminal 113a. The first wiring pattern 114a extends in the long side direction of the frame 110b adjacent to the first electrode pad 111a, and a part of the first wiring pattern 114a is exposed. The second wiring pattern 114b is electrically connected to the other first electrode pad 111b, the other second electrode pad 112b, and the second via conductor 115b. The second via conductor 115b is electrically connected to the second external terminal 113b. Therefore, the other first electrode pad 111b and the other second electrode pad 112b are electrically connected to the second external terminal 113b. The second wiring pattern 114b extends in the long side direction of the frame 110b adjacent to the other first electrode pad 111b, and a part of the second wiring pattern 114b is exposed.

  Thus, a part of the wiring pattern 114 is provided so as to extend from the first electrode pad 111 toward the long side of the frame 110b and to be exposed at the concave portion K. Even when the conductive adhesive 140 overflows from the first electrode pad 111 when mounted, the conductive adhesive 140 flows out along the wiring pattern 114 having good wettability. It is possible to prevent the conductive adhesive 140 from adhering to the excitation electrode 122 without flowing out in the center direction.

  Further, a part of the exposed wiring pattern 114 is provided so as to be symmetric with respect to a straight line L passing through the center point P of the substrate 110a and parallel to the long side of the substrate 110a. A position in which the first wiring pattern 114a thus exposed and the second wiring pattern 114b exposed are symmetrical with respect to a straight line L passing through the center point P of the substrate 110a and parallel to the long side of the substrate 110a. Therefore, even if the conductive adhesive 140 overflows from the first electrode pad 111 when the crystal element 120 is mounted, the amount of the conductive adhesive 140 that overflows becomes uniform. It is easy to suppress the crystal element 120 from being inclined.

  The via conductor 115 is for electrically connecting the external terminal 113 and the wiring pattern 114 or the sealing conductor pattern 118. Both ends of the via conductor 115 are connected to the external terminal 113 and the wiring pattern 114 or the sealing conductor pattern 118. In this way, the external terminal 113 is electrically connected to the wiring pattern 114 or the sealing conductor pattern 118 via the via conductor 115. The via conductor 115 includes a first via conductor 115a, a second via conductor 115b, and a third via conductor 115c. The first via conductor 115a is electrically connected to the first external terminal 113a, and the second via conductor 115b is electrically connected to the second external terminal 113b. The third via conductor 115c is electrically connected to the third external terminal 113c.

  The first bumps 116 are provided as a pair on the first electrode pad 111 so as to be aligned on the same straight line with respect to a straight line parallel to one side of the substrate 110a. In this way, when the extraction electrode 123 of the crystal element 120 is mounted on the first electrode pad 111 while being in contact with the pair of first bumps 116, the crystal element 120 is mounted in a stable state without tilting. Can do.

  A pair of the second bumps 117 are provided on the second electrode pad 112 so as to be aligned with the straight line parallel to one side of the second electrode pad 112 facing the center side of the substrate 110a. Yes. In this way, when the lead electrode 123 of the crystal element 120 is mounted on the first electrode pad 111 and the second electrode pad 112 while being in contact with the pair of second bumps 117, similarly to the first bump 116. The crystal element 120 can be mounted in a stable state without tilting.

  Here, as an example, the dimension of one side when the package 110 is viewed in plan is 1.0 to 2.5 mm, the first electrode pad 111, the second electrode pad 112, the first bump 116, and the second bump. The size of 117 will be described. The length of the side of the first electrode pad 111 parallel to one side of the substrate 110a is 0.25 to 0.40 mm. The length of the side of the first electrode pad 111 that is parallel to the side that intersects with one side of the substrate 110a is 0.25 to 0.40 mm. The length of the thickness of the first electrode pad 111 in the vertical direction is 10 to 50 μm. The length of the side of the second electrode pad 112 that is parallel to one side of the substrate 110a is 0.10 to 0.20 mm. The length of the side of the first electrode pad 111 that is parallel to the side that intersects with one side of the substrate 110a is 0.10 to 0.20 mm. The length of the thickness of the first electrode pad 111 in the vertical direction is 10 to 50 μm. The length of the side of the first bump 116 parallel to one side of the substrate 110a is 0.15 to 0.3 mm. The length of the side of the first bump 116 that is parallel to the side that intersects with one side of the substrate 110a is 50 to 100 μm. The length of the thickness of the first bump 116 in the vertical direction is 7 to 25 μm. The length of the side of the second bump 117 that is parallel to one side of the substrate 110a is 0.8 to 0.15 mm. The length of the side of the second bump 117 that is parallel to the side that intersects with one side of the substrate 110a is 50 to 100 μm. The length of the thickness of the second bump 117 in the vertical direction is 7 to 25 μm. The length between the first bump 116 and the second bump 117 is 80 to 100 μm.

  In addition, the arithmetic average surface roughness of the electrode pad 111 is 0.02 to 0.10 μm, and the arithmetic average surface roughness of the surface of the substrate 110a is 0.5 to 1.5 μm. Therefore, the conductive adhesive 140 is difficult to spread from the first electrode pad 111 and the second electrode pad 112 toward the substrate 110a.

  The sealing conductor pattern 118 plays a role of improving the wettability of the bonding member 131 when bonded to the lid 130 via the bonding member 131. The sealing conductor pattern 118 is formed to have a thickness of, for example, 10 to 25 μm by sequentially applying nickel plating and gold plating on the surface of the conductor pattern made of, for example, tungsten or molybdenum so as to surround the upper surface of the frame 110b in an annular shape. Has been.

  The conductive adhesive 140 is formed so as to spread from the first bump 116 to the second bump 117 in a plan view, and is disposed so as to be spaced from the excitation electrode 122 of the crystal element 120. In the quartz crystal device, the conductive adhesive 140 and the excitation electrode 122 are arranged with a space therebetween, so that a short circuit caused by the conductive adhesive 140 adhering to the excitation electrode 122 can be reduced. .

  As shown in FIG. 3, the conductive adhesive 140 extends from the portion sandwiched between the first bump 116 and the second bump 117 to the excitation electrode 122 of the crystal element 120 beyond the second bump 117. The spread on the first electrode pad 111 and the second electrode pad 112 in the adjacent direction is suppressed by the wettability effect of the wall surface of the second bump 117 and the capillary effect between the first bump 116 and the second bump 117. be able to. Therefore, since the quartz device is difficult to leak and spread in the direction in which the conductive adhesive 140 is sandwiched between the first bump 116 and the second bump 117 and close to the excitation electrode 122 of the quartz element 120, The quartz crystal element 120 can be stably mounted on the first electrode pad 111 and the second electrode pad 112 via the adhesive 140. In addition, since the crystal element 120 can be stably mounted, the oscillation frequency of the crystal element 120 can be output stably.

  In addition, when the conductive adhesive 140 has a viscosity of 35 to 45 Pa · s and is applied to a portion sandwiched between the first bump 116 and the second bump 117, the conductive adhesive 140 140 does not flow over the first bump 116 and the second bump 117 but onto the electrode pad 111, and the first electrode pad 111 and the second electrode pad 112 sandwiched between the first bump 116 and the second bump 117. The thickness in the vertical direction is maintained.

  Further, the conductive adhesive 140 is applied to a portion sandwiched between the first bump 116 and the second bump 117. By doing in this way, the quartz crystal device can make the application amount and application position of the conductive adhesive 140 visually easier to understand.

  In addition, since the conductive adhesive 140 hardly leaks from the first electrode pad 111 and the second electrode pad 112, the thickness of the conductive adhesive 140 in the vertical direction can be secured. The length of the thickness of the conductive adhesive 140 in the vertical direction is 15 to 30 μm. Since the thickness of the conductive adhesive 140 can be ensured in this way, even if an impact applied by a drop test is applied to the crystal element 120 in the vertical direction around the conductive adhesive 140, the impact is made conductive. The adhesive 140 can sufficiently absorb and relax the absorption. In addition, since the conductive adhesive 140 is formed so as to spread from the first bump 116 to the second bump 117, the bonding area between the conductive adhesive 140 and the electrode pad 111, the first bump 116, and the second bump 117. In addition, it is possible to reduce the individual variation between the crystal devices and stabilize the quality.

  Further, as shown in FIG. 4, the conductive adhesive 140 brings the crystal element 120 into contact with the first bump 116 from the released portion between the first bump 116 and the second bump 117. At this time, it spreads over the first electrode pad 111 and the second electrode pad 112 so as to overflow. Therefore, it is possible to reduce the extra conductive adhesive 140 from adhering to the crystal element 120. Further, since the overflowing conductive adhesive 140 spreads on the first electrode pad 111 and the second electrode pad 112, the contact area between the conductive adhesive 140 and the first electrode pad 111 and the second electrode pad 112 is large. Thus, the bonding strength can be improved.

  Here, a method for manufacturing the package 110 will be described. When the substrate 110a and the frame 110b are 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 is prepared. In addition, a predetermined conductor paste is applied to the surface of the ceramic green sheet or a through-hole previously punched by punching the ceramic green sheet by screen printing or the like. Further, these green sheets are laminated and press-molded and fired at a high temperature. Finally, it is manufactured by applying nickel plating or gold plating to predetermined portions of the conductor pattern, specifically, the portions to be the first electrode pad 111, the second electrode pad 112, and the external terminal 113. Moreover, the conductor paste is comprised from the sintered compact etc. of metal powders, such as tungsten, molybdenum, copper, silver, or silver palladium, for example.

  As shown in FIGS. 2 and 3A, 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.

  As shown in FIG. 2, the quartz crystal element 120 has the excitation electrode 122 and the extraction electrode 123 attached to the upper and lower surfaces of the quartz base plate 121, as shown in FIGS. 1 and 2. It has the structure made. The excitation electrode 122 is formed by depositing and forming a metal in a predetermined pattern on each of the upper surface and the lower surface of the quartz base plate 121. 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 crystal base 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 123 a is extracted from the first excitation electrode 122 a and is provided so as to extend toward one side of the crystal base plate 121. The second extraction electrode 123 b is extracted from the second excitation electrode 122 b and is provided so as to extend toward one side of the crystal base plate 121. That is, the extraction electrode 123 is provided in a shape along the long side or the short side of the crystal base plate 121. In the present embodiment, one end of the crystal element 120 connected to one first electrode pad 111a and the other first electrode pad 111b is a fixed end connected to the upper surface of the substrate 110a, and the other end is the substrate 110a. The quartz crystal element 120 is fixed on the substrate 110a by a cantilever supporting structure having a free end spaced from the upper surface of the substrate 110a.

  Further, the quartz crystal device adjusts the oscillation frequency of the quartz crystal element 120 by scraping the surface of the excitation electrode 122 of the quartz crystal element 120 with, for example, an ion gun. Further, in the conventional quartz device, the wiring pattern provided on the upper surface of the substrate is exposed even in the vicinity of the excitation electrode of the crystal element, and therefore the wiring pattern is scraped when the excitation electrode is shaved with an ion gun. There is. Further, in the conventional crystal device, the shavings of the wiring pattern may adhere to the excitation electrode of the crystal element, and the oscillation frequency may fluctuate. However, in the quartz crystal device of this embodiment, as shown in FIG. 4, the wiring pattern 114 is not exposed in the recess K in the vicinity of the excitation electrode 122 of the quartz crystal element 120, and the frame body 110b Since they are provided at the overlapping positions, it is possible to prevent the wiring pattern 114 from being removed when the excitation electrode 122 is removed by the ion gun. Further, since such a quartz crystal device does not generate shavings of the wiring pattern 114, shavings do not adhere to the excitation electrode 122 of the crystal element 120, and an oscillation frequency can be output stably. Become.

  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 manufacturing method of the crystal element 120 will be described. First, the crystal element 120 is cut from the artificial crystalline lens at a predetermined cut angle to reduce the thickness of the outer periphery of the crystal base plate 121, and the central portion of the crystal base plate 121 is thicker than the outer peripheral portion of the crystal base plate 121. The bevel processing provided is performed. The crystal element 120 is manufactured by forming the excitation electrode 122 and the extraction electrode 123 by depositing 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. Is done.

  Further, a manufacturing method for forming such a crystal element 120 by using a photolithography technique and an etching technique will be described. First, a quartz wafer having a crystal axis composed of an X axis, a Y axis, and a Z axis that are orthogonal to each other is prepared. At this time, the main surface of the quartz wafer is a surface obtained by rotating a surface parallel to the X-axis and the Z-axis counterclockwise around the X-axis as viewed in the negative direction of the X-axis, for example, It is parallel to the plane rotated about 37 °. Next, a metal film is formed on both main surfaces of the quartz wafer by using a sputtering technique or a vapor deposition technique, a photosensitive resist is applied on the metal film, and a predetermined pattern is exposed and developed. Allow the wafer to be exposed. In this way, the quartz crystal wafer in which only a predetermined portion is exposed is immersed in a predetermined etching solution, and the quartz crystal wafer is etched. As a result, a plurality of crystal elements 120 are formed in the crystal wafer in a state where some of the crystal elements 120 are connected.

  A method for bonding the crystal element 120 to the substrate 110a will be described. First, the conductive adhesive 140 is applied so as to spread from the first bump 116 to the second bump 117 by, for example, a dispenser. The crystal element 120 is conveyed onto the conductive adhesive 140. Further, the crystal element 120 has an outer peripheral edge on the fixed end side of the crystal base plate 121 that is parallel to one side of the substrate 110a in plan view, and is closer to the outer peripheral edge of the substrate 110a than the first bump 117. It is placed on the conductive adhesive 140. The conductive adhesive 140 is cured and contracted by being heated and cured. When the conductive adhesive 140 is cured and contracted, the crystal element 120 is pulled downward on the fixed end side of the crystal element 120, and the principle of the insulator with the second bump 117 as a fulcrum works. Are joined to the first electrode pad 111 and the second electrode pad 112 in such a manner that the front end of the first electrode pad floats.

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

  The lid body 130 has a rectangular shape, and is for hermetically sealing the concave portion K in a vacuum state or the concave portion K filled with nitrogen gas or the like. Specifically, the lid 130 is placed on the upper surface of the joining member 131 provided on the frame 110b in a predetermined atmosphere. When heat is applied to the joining member 131 provided on the upper surface of the frame 110b, it is melt-joined. The lid 130 is made of an alloy containing at least one of iron, nickel, and cobalt, for example.

  The joining member 131 is provided at a location of the lid 130 facing the sealing conductor pattern 118 provided on the upper surface of the frame 110 b of the package 110. The joining member 131 is provided by, for example, silver solder or gold tin. In the case of silver wax, the 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, the thickness is 10 to 40 μm. For example, the component ratio is 78 to 82% 33 for gold and 18 to 22% for tin.

  For example, when the joining member 131 is gold tin, the thickness of the layer of the joining member 131 is 10 to 40 μm. For example, the component ratio is 70 to 80% for gold and 20 to 30% for tin. May be used. For example, when the joining member 131 is silver brazing, the thickness of the layer of the joining member 131 is 10 to 40 μm. For example, the component ratio is 70 to 80% for silver and 20 to 30% for copper. May be used.

  The quartz crystal device according to the present embodiment has a rectangular substrate 110a and a rectangular shape in plan view, and a pair of first electrode pads 111 provided along one side of the substrate 110a on the substrate 110a and a rectangular shape in plan view. A pair of second electrode pads 112 provided along one side of the first electrode pad 111 facing the center direction of the substrate 110a, and a pair of first bumps 116 provided along one side of the first electrode pad 111. A pair of second bumps 117 provided along one side of the second electrode pad 112; a crystal base plate 121 provided on the substrate 110a; and excitation electrodes provided on the upper and lower surfaces of the crystal base plate 121. 122 and a crystal element 120 having a pair of extraction electrodes 123 provided on the lower surface of the quartz base plate 121 with a space between the excitation electrodes 122, and the extraction electrodes 123 are flat. And vision, is disposed at a position overlapping the first bump 116 and a second bump 117 is connected to the electrode pad through a conductive adhesive 140.

  As described above, the lead electrode 123 is connected to the electrode pad 111 positioned between the first bump 116 and the second bump 117 via the conductive adhesive 140, so that the crystal element is formed when the conductive adhesive 140 is cured and contracted. The fixed end side of 120 is pulled downward, and the tip of the quartz crystal element 120 is lifted by the principle of the insulator using the second bump 117 as a fulcrum. Therefore, the quartz crystal device can reduce contact between the tip of the quartz crystal element 120 and the excitation electrode 122 with the substrate 110a. Further, the quartz crystal device can stably output the oscillation frequency because the thickness shear vibration of the quartz crystal element 120 is not hindered.

  In the crystal device according to the present embodiment, the conductive adhesive 140 is provided between the first bump 116 and the second bump 117 in plan view. By doing in this way, the quartz crystal device can make the application amount and application position of the conductive adhesive 140 visually easier to understand. In addition, since the conductive adhesive 140 hardly leaks from the first electrode pad 111 and the second electrode pad 112, the thickness of the conductive adhesive 140 in the vertical direction can be ensured. Since the thickness of the conductive adhesive 140 can be ensured in this way, even if an impact applied by a drop test is applied to the crystal element 120 in the vertical direction around the conductive adhesive 140, the impact is made conductive. The adhesive 140 can sufficiently absorb and relax the absorption. Further, since the conductive adhesive 140 is formed to spread from the first bump 116 to the second bump 117, the conductive adhesive 140 and the first electrode pad 111, the first bump 116, and the second bump 117 An adhesion area can also be secured.

  Further, the quartz crystal device in the present embodiment is provided such that a pair of second bumps 117 are arranged on the same straight line. In this way, when the lead electrode 123 of the crystal element 120 is mounted on the first electrode pad 111 and the second electrode pad 112 while being in contact with the pair of second bumps 117, the tip end portion and the excitation of the crystal element 120 are excited. In addition to reducing the contact of the working electrode 122 with the substrate 110a, the crystal element 120 can be mounted in a stable state without tilting.

(First modification)
Hereinafter, the crystal device according to the first modification of the present embodiment will be described. Note that, in the quartz crystal device according to the first modification of the present embodiment, the same portions as those of the quartz crystal device described above are denoted by the same reference numerals, and description thereof will be omitted as appropriate. As shown in FIG. 5, the quartz crystal device according to the first modification of the present embodiment has a conductive adhesive 140 between one side of the first electrode pad 111 adjacent to the substrate 110 a and the first bump 116. This is different from the present embodiment in that it is provided.

  In the quartz crystal device according to the first modification of the present embodiment, the conductive adhesive 140 is provided between the side of the first electrode pad 111 on the substrate 110a side and the first bump 116 in plan view. As described above, the lead electrode 123 is connected to the electrode pad 111 positioned between the first bump 116 and the second bump 117 via the conductive adhesive 140, so that the crystal is formed when the conductive adhesive 140 is cured and contracted. The fixed end side of the element 120 is pulled downward, and the tip of the crystal element 120 is lifted by the principle of the insulator with the first bump 116 as a fulcrum. Therefore, the quartz crystal device can reduce contact between the tip of the quartz crystal element 120 and the excitation electrode 122 with the substrate 110a. Further, the quartz crystal device can stably output the oscillation frequency because the thickness shear vibration of the quartz crystal element 120 is not hindered.

  Further, since the crystal element 120 having a size different from that of the embodiment can be mounted like the crystal device of the first modified example of the present embodiment, many types can be made corresponding to the shape of the crystal element of the crystal device. This makes it possible to mount the crystal element 120 having a different shape, so that productivity can be improved.

  In addition, the quartz crystal device according to the first modification of the present embodiment is provided such that the pair of first bumps 116 are arranged on the same straight line. In this way, when the extraction electrode 123 of the crystal element 111 is mounted on the first electrode pad 111 while being in contact with the pair of first bumps 116, the tip of the crystal element 120 and the excitation electrode 122 are connected to the substrate 110a. In addition to reducing contact with the crystal element 120, the crystal element 120 can be mounted in a stable state without tilting.

  In addition, it is not limited to this embodiment, A various change, improvement, etc. are possible in the range which does not deviate from the summary of this invention. In the above embodiment, the case where the frame 110b is integrally formed of a ceramic material in the same manner as the substrate 110a has been described. However, the frame 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.

  In the above embodiment, the case where the frame is provided on the upper surface of the substrate has been described. However, after the crystal element is mounted on the substrate, the crystal element is hermetically sealed using the lid having the wall portion provided on the lower surface. It may be a structure that stops.

  In the above embodiment, the case where an AT crystal element is used as the crystal element has been described. However, a 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.

The crystal element 120 is
You may use the bevel process which makes the thickness of the outer periphery of the crystal base plate 121 thin, and is provided so that the center part of the crystal base plate 121 may become thick compared with the outer peripheral part of the crystal base plate 121. A bevel processing method for the crystal element 120 will be described. A polishing material provided with media and abrasive grains having a predetermined particle size and a quartz base plate 121 having a predetermined size are prepared. The abrasive prepared in the cylindrical body and the quartz base plate 121 are placed, and the open end of the cylindrical body is closed with a cover. The quartz base plate 121 that rotates the cylindrical body containing the abrasive and the quartz base plate 121 with the central axis of the cylindrical body as the rotation axis is polished with the abrasive and beveled.

DESCRIPTION OF SYMBOLS 110 ... Package 110a ... Substrate 110b ... Frame 111 ... First electrode pad 112 ... Second electrode pad 113 ... External terminal 114 ... Wiring pattern 115 ... Via conductor 116: First bump 117 ... Second bump 118 ... Sealing conductor pattern 120 ... Crystal element 121 ... Crystal base plate 122 ... Excitation electrode 123 ... Lead electrode 130 ... Lid 131 ... Joining member 140 ... Conductive adhesive K ... Recess

Claims (5)

A rectangular substrate;
A pair of first electrode pads that are rectangular in plan view and are provided on the substrate along one side of the substrate;
A pair of second electrode pads that are rectangular in plan view and are provided along one side of the first electrode pad that faces the center direction of the substrate;
A pair of first bumps provided along one side of the first electrode pad;
A pair of second bumps provided along one side of the second electrode pad;
A quartz base plate provided on the substrate, excitation electrodes provided on the top and bottom surfaces of the crystal base plate, and a pair of drawers provided on the bottom surface of the crystal base plate with a space between the excitation electrodes. A crystal element having an electrode,
The crystal device, wherein the lead electrode is disposed at a position overlapping the first bump and the second bump in plan view, and is connected to the electrode pad via a conductive adhesive. The crystal device according to claim 1,
The quartz crystal device, wherein the conductive adhesive is provided between the first bump and the second bump in plan view. The crystal device according to claim 1,
The quartz crystal device, wherein the conductive adhesive is provided between a side of the first electrode pad on the substrate side and the first bump in plan view. The quartz crystal device according to claim 1, wherein
A pair of said 1st bumps are provided so that it may be located in a line on the same straight line, The quartz crystal device characterized by the above-mentioned. The crystal device according to claim 1, wherein:
A pair of said 2nd bumps are provided so that it may be located in a line on the same straight line, The quartz crystal device characterized by the above-mentioned.

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