JP2017028592A - Crystal device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a crystal device which achieves easy handling and excellent productivity.SOLUTION: A crystal device includes: a rectangular substrate 110a; a frame body 110b provided along an outer peripheral edge of the substrate 110a; electrode pads 111 provided at four corners exposed on an upper surface of the substrate 110a; protruding parts 114 respectively provided on upper surfaces of the electrode pads 111; a crystal element 120 which is rectangular in a plan view and is mounted on two of the electrode pads 111 through a conductive adhesive 140; and a lid body 130 which hermetically seals the crystal element 120. Corners of the crystal element 120 are provided at positions which overlap with the protruding parts 114 in the plan view.SELECTED DRAWING: Figure 1

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).

JP 2002-111435 A

  In the above-described crystal device, when crystal elements having different mounting positions are used, a substrate corresponding to the mounting position is designed and used. Each time a crystal element having a different mounting position is used, it is necessary to redesign the substrate on which the electrode pad is formed in accordance with the mounting position. Therefore, there is a concern that the productivity of the crystal device may be reduced.

  The present invention has been made in view of the above problems, and it is an object of the present invention to provide a crystal device that is easy to handle and excellent in productivity.

  A quartz crystal device according to an aspect of the present invention includes a rectangular substrate, a frame provided along the outer peripheral edge of the substrate, electrode pads provided at four corners exposed on the upper surface of the substrate, and an upper surface of the electrode pad. A crystal element that is rectangular in plan view and is mounted on the electrode pad via a conductive adhesive, and a lid for hermetically sealing the crystal element. The corner portion of the crystal element is provided at a position overlapping the convex portion in plan view.

  A quartz crystal device according to an aspect of the present invention includes a rectangular substrate, a frame provided along the outer peripheral edge of the substrate, electrode pads provided at four corners exposed on the upper surface of the substrate, and an upper surface of the electrode pad. A crystal element that is rectangular in plan view and is mounted on the electrode pad via a conductive adhesive, and a lid for hermetically sealing the crystal element. The corner of the quartz element is provided at a position that overlaps the convex portion in plan view. By doing so, crystal elements can be mounted on two of the electrode pads provided at the four corners. Therefore, even if crystal elements with different mounting positions are used, the electrode pads suitable for the mounting are used. There is no need to redesign the formed substrate. Therefore, the productivity of the crystal device can be improved.

It is a disassembled perspective view which shows the crystal device in this embodiment. It is sectional drawing in AA of the quartz crystal device shown by FIG. It is a top view which shows the state which removed the cover body 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) The top view which looked at the board | substrate of the package which comprises the crystal device in this embodiment from the top. (A) It is the top view which looked at the package which comprises the crystal device in this embodiment from the bottom. It is a disassembled perspective view which shows the crystal device which concerns on the 1st modification of this embodiment. It is sectional drawing in BB of the quartz crystal device shown by FIG. 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.

  As shown in FIGS. 1 to 5, the crystal device according to the present embodiment includes a package 110, a crystal element 120 bonded to the upper surface of the package 110, and a lid 130 bonded to the upper surface of the package 110. Is included. The package 110 has a recess K surrounded by the upper surface of the substrate 110a and the inner surface of the frame 110b. 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 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 113 and a conductor 115 for electrically connecting the electrode pad 111 provided on the upper surface and the external terminal 112 provided on the lower surface of the substrate 110a are provided on the surface and inside of the substrate 110a. Yes.

  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.

  The electrode pad 111 is for mounting the crystal element 120. Four electrode pads 111 are provided on the upper surface of the substrate 110a. Two electrode pads 111 of the four electrode pads 111 are provided adjacently along one side of the substrate 110a, and the remaining two electrode pads 111 are one side facing one side of the substrate 110a. Two are provided adjacent to each other. The electrode pad 111 includes a first electrode pad 111a, a second electrode pad 111b, a third electrode pad 111c, and a fourth electrode pad 111d. The electrode pad 111 is electrically connected to an external terminal 112 provided on the lower surface of the substrate 110a through a wiring pattern 113 and a conductor portion 115 provided on the substrate 110a.

  The external terminal 112 is used for bonding onto a mounting substrate such as an electronic device. Further, the external terminal 112 is provided on the lower surface of the substrate 110a as shown in FIG. The two terminals of the external terminal 112 are electrically connected to the electrode pad 111 provided on the upper surface of the substrate 110a. One external terminal 112 electrically connected to the electrode pad 111 is provided along the short side of the lower surface of the substrate 110a. The external terminal 112 includes a first external terminal 112a and a second external terminal 112b.

  The wiring pattern 113 is for connecting the electrode pads 111 to each other and electrically connecting to the conductor portion 115. One end of the wiring pattern 113 is electrically connected to the electrode pad 111, and the other end of the wiring pattern 113 is electrically connected to the electrode pad 111 at a position facing the electrode pad 111. The other end of the wiring pattern 113 is electrically connected to the conductor 115. The wiring pattern 113 includes a first wiring pattern 113a and a second wiring pattern 113b.

  Further, the wiring pattern 113 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 113 and the crystal element 120, so that this stray capacitance is not added to the crystal element 120, and therefore the oscillation frequency Can be prevented from fluctuating. 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 electrode pad 111a is electrically connected to the fourth electrode pad 111d through the first wiring pattern 113a, and the fourth electrode pad 111d is connected to the first electrode through the first wiring pattern 111a and the second conductor portion 115b. Two external terminals 112b are connected. That is, the first electrode pad 111a is electrically connected to the second external terminal 112b. The second electrode pad 111b is electrically connected to the third electrode pad 111c via the second wiring pattern 113b, and the second electrode pad 111b is connected via the second wiring pattern 113b and the first conductor portion 115a. Are connected to the first external terminal 112a. That is, the third electrode pad 111c is electrically connected to the first external terminal 112a.

  The convex part 114 is for reducing that the corner | angular part of the crystal element 120 mentioned later contacts the upper surface of the board | substrate 110a. On the electrode pad 111, a pair of convex parts 114 which are rectangular in plan view are provided. In this way, when an impact such as a drop is applied to the crystal device, it is possible to suppress chipping or the like due to the corner portion on the free end side of the crystal element 120 coming into contact with the substrate 110a.

  The four convex portions 114 are configured by a first convex portion 114a, a second convex portion 114b, a third convex portion 114c, and a fourth convex portion 114d. The 1st convex part 114a is provided in the upper surface of the 1st electrode pad 111a, and the 2nd convex part 114b is provided in the upper surface of the 2nd electrode pad 111b. The third convex portion 114c is provided on the upper surface of the third electrode pad 111c, and the fourth convex portion 114d is provided on the upper surface of the fourth electrode pad 111d. Similarly to the electrode pad 111, the protrusion 114 is provided by applying gold plating or nickel plating on the upper surface of a sintered body of metal powder such as tungsten, molybdenum, copper, silver, or silver palladium.

  Further, as shown in FIG. 4A, one side of the convex portion 114 provided on the adjacent electrode pad 111 facing the center side of the substrate 110a is arranged on the same straight line. Yes. By doing so, when the extraction electrode 123 of the crystal element 120 is mounted in contact with the convex portion 114, the crystal element 120 can be mounted in a stable state without being inclined.

  Further, the convex portion 114 is provided at a position facing the extraction electrode 123 on the outer peripheral edge of the crystal element 120. In this way, when the crystal element 120 is mounted on the electrode pad 111 via the conductive adhesive 140, even if the crystal element 120 is inclined, the lead electrode 123 is in contact with the convex portion 114. Thus, the crystal element 120 can be mounted in a stable state without being tilted downward from the convex portion 114. Further, the convex portion 114 is provided at a position overlapping the extraction electrode 123 on the outer peripheral edge of the crystal base plate 121 in plan view. By doing in this way, it can reduce that the corner | angular part which is not fixing the crystal element 120 contacts the upper surface of the board | substrate 110a.

  The conductor 115 is for electrically connecting to the wiring pattern 113 and the external terminal 112. The conductor portion 115 is provided inside a notch provided near the center of the short side of the substrate 110a. Both ends of the conductor portion 115 are connected to the wiring pattern 113 and the external terminal 112. Thus, the electrode pad 111 is electrically connected to the external terminal 112 through the wiring pattern 113 and the conductor portion 115.

  The auxiliary electrode pad 116 is for determining the mounting position of the crystal element 120 when the crystal element 120 is mounted on the electrode pad 111. The auxiliary electrode pad 116 is provided so as to extend from the two electrode pads 111 arranged diagonally toward the electrode pad 111 adjacent in the short side direction. By disposing a part of the auxiliary electrode pad 116 so as to overlap with the extraction electrode 123 of the crystal element 120, the positional deviation of the crystal element 120 such that the outer peripheral edge of the crystal element 120 contacts the package 110 is further reduced. can do.

  Here, when the package 110 is viewed in plan, the dimension of one side is 1.0 to 3.0 mm, and the vertical dimension of the package 110 is 0.7 to 1.5 mm as an example. The size of the pad 111 and the convex part 114 will be described. The side length of the electrode pad 111 is 250 to 400 μm. The length of the thickness of the electrode pad 111 in the vertical direction is 10 to 50 μm. The length of the side of the convex part 114 formed along the outer periphery of the electrode pad 111 is 200 to 350 μm. The length of the thickness of the convex part 114 in the vertical direction is 10 to 30 μm.

  The conductive adhesive 140 is for electrically connecting the extraction electrode 123 of the crystal element 120 and the electrode pad 111. As shown in FIG. 3B, the conductive adhesive 140 is provided so that its outer peripheral edge is in contact with the four sides of the convex portion 114 in plan view. By doing in this way, since the conductive adhesive 140 stays at the outer periphery of the convex portion 114, the conductive adhesive 140 hardly leaks and spreads on the upper surface of the electrode pad 111 or the substrate 110a, and the crystal element 120 is stably attached to the electrode. It can be mounted on the pad 111. In addition, even if the conductive adhesive 140 overflows on the electrode pad 111, it remains at the outer peripheral edge of the electrode pad 111. Therefore, the conductive adhesive 140 is difficult to leak and spread on the upper surface of the substrate 110a. 120 can be mounted on the electrode pad 111. Since the crystal device can stably mount the crystal element 120 on the electrode pad 111, the oscillation frequency of the crystal element 120 can be output stably.

  The conductive adhesive 140 has a circular or elliptical shape when viewed in plan, and is provided at a position where the center point of the conductive adhesive 140 overlaps the center point of the electrode pad 111. In this way, when the crystal element 120 is mounted, the conductive adhesive 140 spreads evenly toward each of the four sides of the electrode pad 111, so that the crystal element 120 is more stably electroded. It can be mounted on the pad 111.

  The conductive adhesive 140 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. .

  Further, by using a conductive adhesive 140 having a viscosity of 35 to 45 Pa · s, the conductive adhesive 140 does not flow from the electrode pad 111 to the upper surface of the substrate 110a when applied. Since it remains on the pad 111, the thickness of the conductive adhesive 140 in the vertical direction can also be secured. The length of the thickness of the conductive adhesive 140 in the vertical direction is 10 to 25 μm. Since the thickness of the conductive adhesive 140 can be ensured in this way, the contact of the crystal element 120 with the substrate 110a is suppressed, and the impact applied by dropping or the like is centered on the conductive adhesive 140 with respect to the crystal element 120. Even when applied in the vertical direction, the impact can be sufficiently absorbed and relaxed by the conductive adhesive 140.

  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.

  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, a predetermined portion of the conductor pattern, specifically, a pair of electrode pads 111 or external terminals 112, a wiring pattern 113, a concave portion 114, and a portion that becomes the conductor portion 115 are produced by applying nickel plating or gold plating or the like. . 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 3, the crystal element 120 is bonded onto the electrode pad 111 via the 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 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 quartz crystal element 120 is fixed on the substrate 110a by a cantilevered support structure with a free end.

  As shown in FIG. 3, the first lead electrode 123a of the crystal element 120 is in contact with the first convex portion 114a, and the second lead electrode 123b of the crystal element 120 is in contact with the second convex portion 114b. Yes. As described above, when the crystal element 120 is mounted on the electrode pad 111 by bringing the extraction electrode 123 of the crystal element 120 into contact with the convex portion 114, the mounting position of the crystal element 120 is shifted and the mounting angle is inclined. The long-side end of the crystal element 120 is supported by being in contact with the convex portion 114, the inclination of the short-side of the crystal element 120 is suppressed, and the long-side end of the crystal element 120 is attached to the substrate 110a or the lid 130. Contact can be prevented. Therefore, fluctuations in the oscillation frequency of the crystal element 120 are prevented, and productivity can be improved.

  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. 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, when the excitation electrode is shaved with an ion gun, the wiring pattern may be shaved. . 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 crystal device of the present embodiment, as shown in FIG. 4, the wiring pattern 113 is not exposed in the recess K in the vicinity of the excitation electrode 122 of the crystal element 120, and the frame 110b in plan view. Therefore, it is possible to prevent the wiring pattern 113 from being removed when the excitation electrode 122 is removed by the ion gun. Further, in such a crystal device, since the shavings of the wiring pattern 113 are not generated, the shavings do not adhere to the excitation electrode 122 of the crystal element 120, and the oscillation frequency can be output stably. Become.

  Further, since the lead electrode 123 of the crystal element 120 comes into contact with the convex portion 114, it is possible to reduce the outer peripheral edge on the fixed end side of the crystal element 120 from coming into contact with the upper surface of the substrate 110a. Accordingly, the crystal element 120 can be prevented from being chipped when the outer peripheral edge of the crystal element 120 on the fixed end side contacts the substrate 110a. Further, even if the crystal element 120 is tilted at the time of mounting, the lead electrode 123 of the crystal element 120 comes into contact with the convex portion 114, so that the fixed end side of the crystal element 120 has a distance corresponding to the vertical thickness of the convex portion 114. Since the free end of the crystal element 120 does not float too much, the free end of the crystal element 120 can be prevented from coming into contact with the lid 130.

  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. Then, the quartz 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 quartz base plate 121 by a photolithography technique, a vapor deposition technique, or a sputtering technique. Is done.

  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 on the electrode pad 111 by, for example, a dispenser. The crystal element 120 is conveyed onto the conductive adhesive 140. Further, the crystal element 120 is placed on the conductive adhesive 140 such that the lead-out electrode 123 on the outer peripheral edge on the fixed end side of the crystal element 120 overlaps the convex portion 114 in plan view. At this time, the overflowing conductive adhesive 140 flows along the exposed first wiring pattern 113a and second wiring pattern 113b. 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 so that the fixed end side of the crystal element 120 is pulled downward, and the free end side of the crystal element 120 is floated upward, so that the first electrode pad 111a. And bonded to the second electrode pad 111b.

  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 body 130 facing the upper surface of the frame 110b of the package 110. The sealing 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% 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 includes a rectangular substrate 110a, a frame 110b provided along the outer peripheral edge of the substrate 110a, electrode pads 111 provided at four corners exposed on the upper surface of the substrate 110a, and an electrode pad. A crystal element 120 having a rectangular shape in plan view and mounted on two of the electrode pads 111 via a conductive adhesive 140; and a crystal element 120. And a lid 130 for hermetically sealing, and the corner of the crystal element 120 is provided at a position overlapping the projection 114 in plan view. By doing in this way, since the crystal element 120 can be mounted on two of the electrode pads 111 provided at the four corners, even if the crystal element 120 having a different mounting position is used, it is adapted to the mounting. There is no need to redesign the substrate on which the electrode pads 111 are formed. Therefore, the productivity of the crystal device can be improved.

  In the crystal device according to the present embodiment, the crystal element 120 includes a rectangular crystal element plate 121, an excitation electrode 122 provided on the upper and lower surfaces of the crystal element plate 121, and an excitation electrode 122. A pair of lead electrodes 123 provided so as to extend to one side of 121, and one of the pair of lead electrodes 123 is electrically connected to the first electrode pad 111a. The other of the lead electrodes 123 is electrically connected to the second electrode pad 111b. By doing in this way, it mounts so that the 3rd electrode pad 112 may be arrange | positioned in the position facing the free end of the crystal | crystallization element 120. FIG. Therefore, the free end of the crystal element 120 is in contact with the third electrode pad 111c and / or the fourth electrode pad 111d even if it is tilted about the place where the extraction electrode 123 of the crystal element 220 and the electrode pad 111 are joined. Therefore, it is possible to suppress the free end of the crystal element 120 from coming into contact with the upper surface of the substrate 110a. If a drop test or the like is performed in a state where the free end of the crystal element 120 is in contact with the substrate 110a, the free end of the crystal element 120 may be lost. By doing in this way, it can suppress that the free end side of the crystal element 120 is missing, and it can reduce that the oscillation frequency of the crystal element 120 fluctuates.

  In the quartz crystal device according to the present embodiment, the auxiliary electrode pads 116 provided so as to extend toward the electrode pads 111 adjacent to each other in the short side direction are provided on the two electrode pads 111 arranged diagonally. Is provided. In this way, when the crystal element 120 is mounted, the lead electrode 123 of the crystal element 120 and a part of the auxiliary electrode pad 116 are arranged so as to overlap in plan view. The positional deviation of the crystal element 120 such that the outer peripheral edge of the quartz crystal element 120 contacts the package 110 can be reduced.

  The quartz crystal device in the present embodiment is provided such that the conductive adhesive 140 is located in the convex portion 114 in plan view. That is, the outer peripheral edge of the conductive adhesive 140 is provided so as to be in contact with the four sides of the convex portion 114 in a plan view as shown in FIG. By doing in this way, since the conductive adhesive 140 stays at the outer periphery of the convex portion 114, the conductive adhesive 140 hardly leaks and spreads on the upper surface of the electrode pad 111 or the substrate 110a, and the crystal element 120 is stably attached to the electrode. It can be mounted on the pad 111. In addition, even if the conductive adhesive 140 overflows on the electrode pad 111, it remains at the outer peripheral edge of the electrode pad 111. Therefore, the conductive adhesive 140 is difficult to leak and spread on the upper surface of the substrate 110a. 120 can be mounted on the electrode pad 111. Since the crystal device can stably mount the crystal element 120 on the electrode pad 111, the oscillation frequency of the crystal element 120 can be output stably.

  In the quartz crystal device according to the present embodiment, the wiring pattern 113 is electrically connected to the electrode pad 111, and is provided at a position overlapping the frame 110b when viewed in plan. By doing so, the crystal device can suppress the generation of stray capacitance between the wiring pattern 113 and the crystal element 120. Further, in such a crystal device, since the stray capacitance is not given to the crystal element 120, it is possible to reduce the fluctuation of the oscillation frequency. Further, in the crystal device according to the present embodiment, 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. The portion where the body 110b is provided is 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 of the crystal device can be prevented from being output.

(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 FIGS. 6 to 8, the crystal device according to the first modification of the present embodiment is different from the present embodiment in that the crystal element 220 has a both-end support structure.

  As shown in FIGS. 6 to 8, the crystal element 220 has a structure in which the excitation electrode 222 and the extraction electrode 223 are attached to the upper surface and the lower surface of the crystal base plate 221, respectively. The excitation electrode 222 is formed by depositing and forming a metal in a predetermined pattern on the upper and lower surfaces of the quartz base plate 221. The excitation electrode 222 includes a first excitation electrode 222a on the upper surface and a second excitation electrode 222b on the lower surface. The extraction electrode 223 extends from the excitation electrode 222 toward the opposite sides of the crystal base plate 221. The extraction electrode 223 includes a first extraction electrode 223a on the upper surface and a second extraction electrode 223b on the lower surface. The first extraction electrode 223 a is extracted from the first excitation electrode 222 a and is provided so as to extend toward one side of the crystal base plate 121. The second extraction electrode 223 b is extracted from the second excitation electrode 222 b and is provided so as to extend toward the other side of the crystal base plate 221. In addition, such a crystal element 220 is fixed on the substrate 110a by a both-end support structure at a position located diagonally to the crystal base plate 221.

  A method for bonding the crystal element 220 to the substrate 110a will be described. First, the conductive adhesive 140 is applied onto the first electrode pad 111a and the third electrode pad 111c by, for example, a dispenser. The crystal element 220 is transported on the conductive adhesive 140 and placed on the conductive adhesive 140. The conductive adhesive 140 is cured and contracted by being heated and cured. The crystal element 220 is bonded to the electrode pad 111. That is, the first extraction electrode 223a of the crystal element 220 is bonded to the first electrode pad 111a, and the second extraction electrode 223b is bonded to the third electrode pad 111c. As a result, the first external terminal 112 a and the second external terminal 112 b are electrically connected to the crystal element 220.

  In the quartz crystal device according to the first modification of the present embodiment, the electrode pad 111 includes the first electrode pad 111a, the second electrode pad 111b, the third electrode pad 111c, and the fourth electrode pad 111d. A rectangular crystal base plate 221, an excitation electrode 222 provided on the upper and lower surfaces of the crystal base plate 221, and an extension electrode 222 are provided so as to extend toward opposite sides of the crystal base plate 221. A pair of lead electrodes 223, one of the pair of lead electrodes 223 and the first electrode pad 111a are electrically connected, and the other of the pair of lead electrodes 223 and the third electrode pad 111c is electrically connected. By doing so, since the crystal element 220 can be mounted on the first electrode pad 111a and the third electrode pad 111c that are diagonal to each other, even if crystal elements having different mounting positions are used, There is no need to redo the design of the package 110 on which the electrode pads 111 are formed. Therefore, the productivity of the crystal device can be improved.

  Further, in the quartz crystal device according to the first modification of the present embodiment, the quartz crystal element 220 includes a rectangular quartz base plate 221, an excitation electrode 222 provided on the upper and lower surfaces of the quartz base plate 221, and an excitation electrode 222. And a pair of extraction electrodes 223 provided so as to extend toward both opposite sides of the quartz base plate 221, and one of the pair of extraction electrodes 223 and the first electrode pad 111a are electrically connected to each other. The other of the pair of lead electrodes 223 and the third electrode pad 111c are electrically connected. By doing so, even if the first lead electrode 223a and the second lead electrode 223b of the crystal element 220 are tilted about the place where the first electrode pad 111a and the third electrode pad 111c are joined, the crystal One corner where the element 220 is not bonded contacts the second convex portion 114b of the second electrode pad 111b, and the other corner is separated from the substrate 110a, so that the crystal element 220 is bonded to the upper surface of the substrate 110a. It can suppress that the corner which is not touching. If a drop test or the like is performed in a state where the corner where the crystal element 220 is not bonded is in contact with the substrate 110a, the corner where the crystal element 220 is not bonded may be lost. By doing so, it is possible to reduce the fluctuation of the oscillation frequency of the crystal element 220 while suppressing the corner of the crystal element 220 from being lost regardless of the inclination with respect to the axis described above. .

  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 provided on the upper surface of the substrate 110a has been described. However, after the crystal element is mounted on the substrate, the lid having the sealing frame provided on the lower surface of the sealing base is provided. The quartz element may be hermetically sealed. The lid is composed of a rectangular sealing base and a sealing frame portion provided along the outer peripheral edge of the lower surface of the sealing base. The lower surface of the sealing base and the inner side of the sealing frame portion An accommodation space is formed with the side surface. The sealing frame portion is for forming an accommodation space on the lower surface of the sealing base. The sealing frame part is provided along the outer edge of the lower surface of the sealing base.

  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 includes a crystal piece, an excitation electrode provided on the surface of the crystal piece, an extraction electrode, and a metal film for frequency adjustment. The crystal piece includes a crystal base portion and a crystal vibration portion, and the crystal vibration portion includes a first crystal vibration portion and a second crystal vibration portion. The crystal base has an orthogonal coordinate system in which the electrical axis is the X axis, the mechanical axis is the Y axis, and the optical axis is the Z axis as the crystal axis direction, within a range of −5 ° to + 5 ° around the X axis. This is a flat plate having a substantially rectangular shape in a plan view in which the direction of the rotated Z ′ axis is the thickness direction. The first crystal vibrating part and the second crystal vibrating part are extended in parallel with the Y′-axis direction from one side of the crystal base part. Such a crystal piece has a tuning fork shape in which a crystal base and each crystal vibration part are integrated, and is manufactured by a photolithography technique and a chemical etching technique.

DESCRIPTION OF SYMBOLS 110 ... Package 110a ... Board | substrate 110b ... Frame body 111 ... Electrode pad 112 ... External terminal 113 ... Wiring pattern 114 ... Convex part 115 ... Conductor part 116 ... Auxiliary electrode pads 120, 220 ... crystal elements 121, 221 ... crystal base plates 122, 222 ... excitation electrodes 123, 223 ... extraction electrodes 130 ... lid body 131 ... bonding member 140 ... Conductive adhesive K ... Recess

Claims (6)

A rectangular substrate;
A frame provided along the outer peripheral edge of the substrate;
Electrode pads provided at the four corners exposed on the upper surface of the substrate;
A convex portion provided on the upper surface of the electrode pad;
A quartz crystal element that is rectangular in plan view and is mounted on two of the electrode pads via a conductive adhesive;
A lid for hermetically sealing the crystal element,
A crystal device, wherein a corner portion of the crystal element is provided at a position overlapping the convex portion in plan view. The crystal device according to claim 1,
The electrode pad comprises a first electrode pad, a second electrode pad, a third electrode pad, and a fourth electrode pad,
The crystal element is provided so as to extend from a rectangular crystal base plate, excitation electrodes provided on the upper and lower surfaces of the crystal base plate, and one side of the crystal base plate from the excitation electrode. A pair of lead electrodes provided,
One of the pair of extraction electrodes and the first electrode pad are electrically connected, and the other of the pair of extraction electrodes and the second electrode pad are electrically connected. Crystal device. The crystal device according to claim 1,
The electrode pad comprises a first electrode pad, a second electrode pad, a third electrode pad, and a fourth electrode pad,
The crystal element extends from the rectangular crystal base plate, excitation electrodes provided on the top and bottom surfaces of the crystal base plate, and both sides of the crystal base plate facing each other from the excitation electrode. A pair of lead electrodes provided as
One of the pair of lead electrodes and the first electrode pad are electrically connected, and the other of the pair of lead electrodes and the third electrode pad are electrically connected. Crystal device. The quartz crystal device according to claim 1, wherein
A quartz crystal device, wherein two electrode pads arranged diagonally are provided with auxiliary electrode pads provided so as to extend toward electrode pads adjacent to each other in the short side direction. The crystal device according to claim 1, wherein:
The crystal device, wherein the conductive adhesive is provided so as to be located in the convex portion in plan view. The quartz crystal device according to claim 1, wherein
The quartz crystal device, wherein the wiring pattern is electrically connected to the electrode pad, and is provided at a position overlapping the frame when viewed in plan.

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