JP2016220058A - Crystal oscillator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a crystal oscillator capable of suppressing a package from chipping by improving the bonding strength between a conductive bonding material and a thermosensor.SOLUTION: A crystal oscillator comprises: a rectangular substrate 110a; a first frame body 110b; a second frame body 110c; a pair of electrode pads 111 provided on the substrate 110a in a first recess K1 formed in the substrate 110a and the first frame body 110b; a pair of connection pads 117 provided on the substrate 110a in a second recess K2; external terminals 112 provided at four corners of a lower surface of the second frame body 110c; a crystal element 120 mounted on the electrode pad 111; a thermosensor 150 mounted on the connection pads 117 via conductive bonding materials 170; and a lid 130 bonded to an upper surface of the first frame body 110b. In a plan view, an opening of the second recess K2 is polygonal, and a corner C of the opening of the second recess K2 is provided so as to be located between adjacent external terminals 112.SELECTED DRAWING: Figure 4

Description

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

  The crystal resonator generates a specific frequency by using the piezoelectric effect of the crystal element. For example, a package having a substrate, a first frame provided on the upper surface of the substrate for providing the first recess, and a second frame provided on the lower surface of the substrate for providing the second recess. And a crystal resonator that is mounted on an electrode pad provided on the upper surface of the substrate and a temperature sensitive device that is mounted on a connection pad provided on the lower surface of the substrate has been proposed (for example, , See Patent Document 1 below).

JP 2012-80250 A

  In the above-described quartz resonator, the temperature sensitive element is mounted in the second recess using a conductive bonding material such as solder. Since the miniaturization is progressing and the area of the connection pad formed in the second recess is also reduced, the amount of the conductive bonding material provided in the connection pad is reduced, and the conductive bonding material and the temperature sensitive element are reduced. There was a possibility that the bonding strength would decrease. In addition, such a crystal resonator has a smaller shape when seen in plan view of the second recess, so that when mounting the temperature-sensitive element in the second recess, the mounting nozzle becomes the inner wall of the second recess. There was a risk that the package would be chipped.

  The present invention has been made in view of the above problems, and provides a crystal resonator capable of improving the bonding strength between a conductive bonding material and a temperature-sensitive element and suppressing the occurrence of chipping in a package. Let it be an issue.

  A crystal resonator according to one aspect of the present invention includes a rectangular substrate, a first frame provided on the upper surface of the substrate, a second frame provided on the lower surface of the substrate, and the substrate and the first frame. A pair of electrode pads provided on the upper surface of the substrate in the first recess formed in the above and a pair of connection pads provided on the lower surface of the substrate in the second recess formed by the substrate and the second frame body An external terminal provided at the four corners of the lower surface of the second frame, a crystal element mounted on the electrode pad, a temperature sensitive element mounted on the connection pad via a conductive bonding material, and the first frame A lid joined to the upper surface of the second recess, the shape of the opening of the second recess is polygonal in plan view, and the corner of the opening of the second recess is adjacent in plan view It is provided so that it may be located between the external terminals which do.

  A crystal resonator according to one aspect of the present invention includes a rectangular substrate, a first frame provided on the upper surface of the substrate, a second frame provided on the lower surface of the substrate, and the substrate and the first frame. A pair of electrode pads provided on the upper surface of the substrate in the first recess formed in the above and a pair of connection pads provided on the lower surface of the substrate in the second recess formed by the substrate and the second frame body An external terminal provided at the four corners of the lower surface of the second frame, a crystal element mounted on the electrode pad, a temperature sensitive element mounted on the connection pad via a conductive bonding material, and the first frame A lid joined to the upper surface of the second recess, the shape of the opening of the second recess is polygonal in plan view, and the corner of the opening of the second recess is adjacent in plan view It is provided so as to be positioned between the external terminals. By doing so, since the shape of the second recess can be increased in the crystal resonator, the area of the connection pad can be increased as compared with the case where the conventional crystal resonator is downsized. Therefore, the amount of the conductive bonding material provided on the connection pad can be secured, and the bonding strength between the conductive bonding material and the temperature sensitive element can be improved. In addition, since such a crystal resonator can also increase the shape of the second recess when viewed in plan, when mounting a temperature-sensitive element in the second recess, the mounting nozzle is connected to the inner wall of the second recess. Therefore, the occurrence of chipping in the package can be reduced.

It is a disassembled perspective view which shows the crystal resonator which concerns on this embodiment. It is AA sectional drawing of FIG. It is the top view seen from the upper surface in the state which removed the lid of the crystal oscillator concerning this embodiment. It is the top view which looked at the crystal oscillator concerning this embodiment from the lower surface. (A) is the plane perspective view which looked at the package which comprises the crystal oscillator concerning this embodiment from the upper surface, (b) looked at the board | substrate of the package which comprises the crystal oscillator concerning this embodiment from the upper surface. It is a plane perspective view. (A) is the plane perspective view which looked at the substrate of the package which constitutes the crystal oscillator concerning this embodiment from the undersurface, and (b) looked at the package which constitutes the crystal oscillator concerning this embodiment from the undersurface It is a plane perspective view. (A) is the plane perspective view which looked at the substrate of the package which constitutes the crystal oscillator concerning the 1st modification of this embodiment from the lower surface, and (b) is the crystal concerning the 1st modification of this embodiment It is the plane perspective view which looked at the package which comprises a vibrator from the lower surface.

  As shown in FIGS. 1 to 5, the crystal resonator according to the present embodiment includes a package 110, a crystal element 120 bonded to the upper surface of the package 110, and a temperature sensitive element bonded to the lower surface of the package 110. 150. The package 110 has a first recess K1 surrounded by the upper surface of the substrate 110a and the inner surface of the first frame 110b. A second recess K2 surrounded by the lower surface of the substrate 110a and the inner surface of the second frame 110c is formed. Such a crystal resonator 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 and the temperature sensitive 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 117 for mounting the temperature sensitive element 150 on the lower surface. A first electrode pad 111a and a second electrode pad 111b for bonding the crystal element 120 are provided along one side 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 via conductor 114 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 and inside the substrate 110a. Yes. Further, a connection pattern 118 for electrically connecting the connection pads 117 provided on the lower surface and the external terminals 112 provided on the lower surface of the second frame 110b is provided on the surface of the substrate 110a. .

  The first frame 110b is disposed along the outer peripheral edge of the upper surface of the substrate 110a, and is for forming the first recess K1 on the upper surface of the substrate 110a. The first frame 110b is made of a ceramic material such as alumina ceramic or glass-ceramic, and is formed integrally with the substrate 110a. The opening of the first recess K1 has a rectangular shape when viewed from above.

  The second frame 110c is disposed along the outer peripheral edge of the lower surface of the substrate 110a, and is for forming the second recess K2 on the lower surface of the substrate 110a. The second frame 110c is made of a ceramic material such as alumina ceramic or glass-ceramic, and is formed integrally with the substrate 110a. External terminals 112 are provided at the four corners of the lower surface of the second frame 110c. Two of the four external terminals 112 are electrically connected to the crystal element 120. Further, the remaining two of the four external terminals 112 are electrically connected to the temperature sensing element 150. In addition, the first external terminal 112a and the second external terminal 112b that are electrically connected to the crystal element 120 are provided so as to be positioned diagonally on the lower surface of the second frame 110c. The third external terminal 112c and the fourth external terminal 112d that are electrically connected to the temperature sensing element 150 are provided with a first external terminal 112a and a second external terminal 112b that are connected to the crystal element 120. It is provided so that it may be located in the diagonal of the 2nd frame 110c different from the diagonal which exists.

  The opening of the second recess K2 has a polygonal shape when viewed in plan. Further, as shown in FIGS. 4 and 6B, at least one corner C of the opening of the second recess K <b> 2 is provided between the adjacent external terminals 112. That is, when viewed in a plan view, two corners C5 and C6 are provided between the second external terminal 112b and the third external terminal 112c, and the second external terminal 112b and the fourth external terminal Two corners C3 and C4 are provided between the terminal 112d and the terminal 112d. Further, two corners C7 and C8 are provided between the first external terminal 112a and the third external terminal 112c, and between the first external terminal 112a and the fourth external terminal 112d. Is provided so that the two corners C1 and C2 are located.

  In this way, since the space between the adjacent external terminals 112 can be used, the area of the opening of the second recessed portion K2 is the same as that of the second recessed portion K2 when the conventional crystal unit is downsized. Since it can be made larger than the area of the opening, the area of the connection pad 117 can also be increased. Therefore, the amount of the conductive bonding material 170 provided on the connection pad 117 can be secured, and the bonding strength between the conductive bonding material 170 and the temperature sensitive element 150 can be improved. Further, since the mounting nozzle is prevented from coming into contact with the inner wall of the second recess K2 when mounting the temperature sensitive element 150 in the second recess K2, it is possible to reduce the occurrence of chipping in the package 110. .

  In the present embodiment, the opening of the second recess K2 is formed in an octagonal shape in plan view, so that the exposed area of the substrate 110a is larger than when the opening is circular. Therefore, the area of the connection pad 117 can be increased. Therefore, the amount of the conductive bonding material 170 provided on the connection pad 117 can be secured, and the bonding strength between the conductive bonding material 170 and the temperature sensitive element 150 can be improved.

  Moreover, the corner | angular part C of the opening part of the 2nd recessed part K2 is formed in circular arc shape. By doing in this way, even when stress is applied to the package 110 when the piezoelectric device of the present embodiment is mounted on the mounting board of the electronic device, the corner portion C has an arc shape. It is possible to reduce the occurrence of cracks in the package 110 due to dispersion of the stress applied to the package 110. Moreover, the curvature radius of the corner | angular part C used as circular arc shape is 0.10-0.20 mm.

  Here, the case where the dimension of one side when the package 110 is viewed in plan 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 is taken as an example. The sizes of the first recess K1 and the second recess K2 will be described. The length of the long side of the first recess K1 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 1st recessed part K1 is 0.1-0.5 mm. The length of the side of the second recess K2 parallel to the short side of the substrate 110a is 0.3 to 0.8 mm, and the length of the side of the second recess K2 parallel to the long side of the substrate 110a is It is 0.6 to 2.0 mm. Moreover, the length of the up-down direction of the 2nd recessed part K2 is 0.1-0.5 mm.

  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 5, the electrode pad 111 is electrically connected to the external terminal 112 provided on the lower surface of the substrate 110a through 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 FIGS. 3 and 5, the electrode pad 111 includes a first electrode pad 111 a and a second electrode pad 111 b. As shown in FIGS. 4 and 6B, the external terminal 112 includes a first external terminal 112a, a second external terminal 112b, a third external terminal 112c, and a fourth external terminal 112d. The via conductor 114 includes a first via conductor 114a, a second via conductor 114b, a third via conductor 114c, and a fourth via conductor 114d. The wiring pattern 113 is composed of a first wiring pattern 113a and a second wiring pattern 113b. The first electrode pad 111a is electrically connected to one end of the first wiring pattern 113a provided on the substrate 110a. The other end of the first wiring pattern 113a is electrically connected to the first external terminal 112a through the first via conductor 114a. Therefore, the first electrode pad 111a is electrically connected to the first external terminal 112a. The second electrode pad 111b is electrically connected to one end of the second wiring pattern 113b provided on the substrate 110a. The other end of the second wiring pattern 113b is electrically connected to the second external terminal 112b through the second via conductor 114b.

  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 spreads in the direction of the wiring pattern 113 where the convex portions 115 on the electrode pad 111 are not provided, but the conductive adhesive 140 spreads from the electrode pad 111 to the substrate. It becomes difficult to spread toward 110a.

  The external terminal 112 is used for electrical connection with a mounting board (not shown) such as an electronic device. The external terminals 112 are provided at the four corners of the lower surface of the second frame 110c. Two of the external terminals 112 are electrically connected to a pair of electrode pads 111 provided on the upper surface of the substrate 110a. The other two terminals of the external terminals 112 are electrically connected to a pair of connection pads 117 provided on the lower surface of the substrate 110a. The external terminals 112 that are electrically connected to the electrode pads 111 are provided so as to be located diagonally on the lower surface of the substrate 110a. The third external terminal 112c is electrically connected to the sealing conductor pattern 119 through the third via conductor 114c. The first external terminal 112a has a shape that is chamfered at a position facing the hypotenuse connecting the corner C1 and the corner C8, and the second external terminal 112b has a corner C4 and a corner C5. Chamfering is performed at a position facing the hypotenuse connecting the two. The third external terminal 112c has a shape that is chamfered at a position opposite to the hypotenuse connecting the corner C6 and the corner C7, and the fourth external terminal 112d has a corner C2 and a corner. Chamfering is performed at a position opposite to the hypotenuse connecting the part C3. In this way, when the crystal resonator of the present embodiment is mounted on a mounting substrate such as an electronic device, the solder provided on the external terminal 112 is crushed and enters the second recess K2. Can be reduced.

  The wiring pattern 113 is provided on the upper surface of the substrate 110a, and is drawn from the electrode pad 111 toward the neighboring via conductor 114. Moreover, the wiring pattern 113 is comprised by the 1st wiring pattern 113a and the 2nd wiring pattern 113b, as shown in FIG.

  The via conductor 114 is provided inside the substrate 110a, and both ends thereof are electrically connected to the wiring pattern 113, the connection pattern 118, or the sealing conductor pattern 119. The via conductor 114 is provided by filling a conductor in a through hole provided in the substrate 110a. The via conductor 114 includes a first via conductor 114a, a second via conductor 114b, a third via conductor 114c, and a fourth via conductor 114d, as shown in FIGS.

  The convex 115 is intended to suppress the vertical inclination of the short side of the crystal element 120 and to prevent the end of the long side of the crystal element 120 from coming into contact with the substrate 110 a and the lid 130. Moreover, the convex part 115 is for suppressing that the free end of the crystal | crystallization element 120 contacts the board | substrate 110a. A pair of convex part 115 is comprised by the 1st convex part 115a and the 2nd convex part 115b. The first convex portion 115a is provided on the upper surface of the first electrode pad 111a, and the second convex portion 115b is provided on the upper surface of the second electrode pad 111b. Similarly to the electrode pad 111, the protrusion 115 is provided by performing 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.

  Also, one side of the pair of convex portions 115 facing the center side of the substrate 110a is provided so as to be aligned on the same straight line as shown in FIGS. In this way, when the extraction electrode 123 of the crystal element 120 is mounted on the electrode pad 111 while being in contact with the pair of convex portions 115, the crystal element 120 can be mounted in a stable state without being inclined.

  Further, the convex portion 115 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 115. Thus, the crystal element 120 can be mounted in a stable state without being tilted downward from the convex portion 115. Further, the projection 115 is provided at a position overlapping with the extraction electrode 123 on the outer peripheral edge of the crystal base plate 121 on the fixed end side in plan view. By doing in this way, it can reduce that the fixed end of crystal element 120 contacts the upper surface of substrate 110a.

  The projection 116 is rectangular in plan view and is provided at a position facing the free end side of the crystal element 120 to prevent the free end side of the crystal element 120 from contacting the substrate 110a. It is. The protrusion 116 is provided on the substrate 110a in the first recess K1 so that the long side of the protrusion 116 and the long side of the substrate 110a are substantially parallel. By doing so, it is possible to suppress chipping or the like due to the free end side of the crystal element 120 coming into contact with the substrate 110a when an impact such as dropping is applied to the crystal resonator.

  The connection pad 117 has a rectangular shape and is used for mounting a temperature sensitive element 150 described later. The connection pads 117 are provided as a pair so as to be adjacent to the vicinity of the center of the lower surface of the substrate 110a. Further, as shown in FIG. 6, the connection pad 117 includes a first connection pad 117a and a second connection pad 117b. The conductive bonding material 170 is provided between the lower surface of the connection pad 117 and the connection terminal 151 of the temperature-sensitive element 150, and the conductive bonding material 170 is connected from the connection pad 117 to the connection terminal 151 of the temperature-sensitive element 150. A slope is formed so that the thickness gradually increases toward the surface. That is, a fillet of the conductive bonding material 170 is formed on the connection pad 117. By forming the fillet in this way, the temperature sensitive element 150 can improve the bonding strength with the connection pad 117.

  The second connection pad 117b is provided so as to be positioned between the pair of electrode pads 111 in plan view. Further, by doing so, the heat transferred from the crystal element 120 is transferred to the second connection pad 117b through the substrate 110a located immediately below the electrode pad 111. Therefore, since such a crystal resonator can further shorten the heat conduction path, the temperature of the crystal element 120 and the temperature of the temperature sensing element 150 are approximated and output from the temperature sensing element 150. It becomes possible to further reduce the difference between the temperature obtained by converting the voltage and the actual temperature around the quartz crystal element 120.

  Here, when the board 110a is viewed in plan, the long side dimension is 1.2 to 2.5 mm, and the short side dimension is 1.0 to 2.0 mm as an example. Explain the size of. The length of the side of the connection pad 117 parallel to the short side of the substrate 110a is 0.2 to 0.5 mm, and the length of the side parallel to the long side of the substrate 110a is 0.25 to 0.55 mm. It has become. Further, the length between the first connection pad 117a and the second connection pad 117b is 0.1 to 0.3 mm.

  The first connection pad 117a and the third external terminal 112c are connected by a first connection pattern 118a and a third via conductor 114c provided on the lower surface of the substrate 110a. The second connection pad 117b and the fourth external terminal 112d are connected by a second connection pattern 118b and a fourth via conductor 114d provided on the lower surface of the substrate 110a.

  The connection pattern 118 is provided on the lower surface of the substrate 110a, and is drawn out from the connection pad 117 toward the external terminal 112 in the vicinity. Further, as shown in FIGS. 4 and 6, the connection pattern 118 includes a first connection pattern 118a and a second connection pattern 118b. The length of the first connection pattern 118a and the length of the second connection pattern 118b are substantially equal. Here, the substantially equal length means that the difference between the length of the first connection pattern 118a provided on the lower surface of the substrate 110a and the length of the second connection pattern 118b provided on the lower surface of the substrate 110a is different by 0 to 200 μm. Shall be included. The length of the connection pattern 118 is obtained by measuring the length of a straight line passing through the center of each connection pattern 118. That is, when the wiring length of the first connection pattern 118a and the wiring length of the second connection pattern 118b are substantially equal, the generated resistance values are equal, and the load resistance applied to the temperature sensing element 150 is also uniform. Therefore, it becomes possible to output a voltage stably.

  The second connection pattern 118b is provided so as to overlap the first electrode pad 111a in plan view. Moreover, by doing in this way, the heat transmitted from the crystal element 120 is transmitted from the second connection pattern 118b to the second connection pad 117b through the substrate 110a immediately below the first electrode pad 111a. Therefore, in such a crystal resonator, the temperature of the crystal element 120 and the temperature of the thermosensitive element 150 are approximated by further shortening the heat conduction path and further increasing the number of heat conduction paths. It is possible to further reduce the difference between the temperature obtained by converting the voltage output from the temperature element 150 and the temperature around the actual crystal element 120.

  The sealing conductor pattern 119 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 119 is provided so as to surround the upper surface of the first frame 110b. As shown in FIGS. 5 and 6, the sealing conductor pattern 119 is electrically connected to the third external terminal 112c via the third via conductor 114c. The sealing conductor pattern 119 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 tungsten, molybdenum, or the like in a manner surrounding the upper surface of the first frame 110b in an annular shape. Is formed.

  Here, a method for manufacturing the substrate 110a will be described. When the substrate 110a is made of alumina ceramic, 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, nickel plating is applied to a predetermined portion of the conductor pattern, specifically, the electrode pad 111, the external terminal 112, the wiring pattern 113, the via conductor 114, the connection pad 117, the connection pattern 118, and the sealing conductor pattern 119. Moreover, it produces by giving gold plating, silver palladium, etc. 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. 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 an excitation electrode 122 and an extraction electrode 123 are attached to an upper surface and a lower surface of a crystal base plate 121, respectively. . 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 quartz 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.

  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.

  A method for bonding 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 a dispenser, for example. The crystal element 120 is transported onto 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 120 is bonded to the electrode pad 111. That is, the first lead electrode 123a of the crystal element 120 is joined to the first electrode pad 111a, and the second lead electrode 123b is joined to the second electrode pad 111b. As a result, the first external terminal 112 a and the second external terminal 112 b are electrically connected to the crystal element 120.

  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.

  As the temperature sensing element 150, a thermistor, a platinum resistance thermometer, a diode, or the like is used. In the case of the thermistor element, the temperature sensing element 150 has a rectangular parallelepiped shape, and is provided with connection terminals 151 at both ends. The temperature sensing element 150 shows a remarkable change in electrical resistance due to a change in temperature. Since the voltage changes due to the change in resistance value, the output depends on the relationship between the resistance value and voltage and the relationship between voltage and temperature. Temperature information can be obtained from the applied voltage. The temperature sensing element 150 outputs a voltage between connection terminals 151, which will be described later, to the outside of the crystal resonator via the third external terminal 112c and the fourth external terminal 112d. Temperature information can be obtained by converting the voltage output at (not shown) into temperature. Such a temperature sensitive element 150 is arranged near the crystal resonator, and the voltage for driving the crystal resonator is controlled by the main IC in accordance with the temperature information of the crystal resonator obtained thereby, so-called temperature compensation. Can do.

In the case where a platinum resistance thermometer is used, the temperature sensing element 150 is provided with a platinum electrode by depositing platinum at the center of a rectangular parallelepiped ceramic plate. Connection terminals 151 are provided at both ends of the ceramic plate. The platinum electrode and the connection terminal are connected by a lead electrode provided on the upper surface of the ceramic plate. An insulating resin is provided so as to cover the upper surface of the platinum electrode.

  When a diode is used, the temperature sensing element 150 has a structure in which a semiconductor element is mounted on an upper surface of a semiconductor element substrate and the upper surface of the semiconductor element and the semiconductor element substrate is covered with an insulating resin. . Connection terminals 151 serving as an anode terminal and a cathode terminal are provided from the bottom surface to the side surface of the semiconductor element substrate. The temperature sensing element 150 has a forward characteristic in which current flows from the anode terminal to the cathode terminal, but hardly flows current from the cathode terminal to the anode terminal. The forward characteristics of the temperature sensitive element vary greatly depending on the temperature. Voltage information can be obtained by passing a constant current through the temperature sensing element and measuring the forward voltage. By converting from the voltage information, temperature information of the crystal element can be obtained. In the diode, the relationship between voltage and temperature shows a straight line. The voltage between the cathode terminal and the anode terminal of the connection terminal 151 is output to the outside of the crystal resonator via the third external terminal 112c and the fourth external terminal 112d.

  As shown in FIGS. 2 and 4, the temperature sensing element 150 is mounted on a connection pad 117 provided on the lower surface of the substrate 110 a via a conductive bonding material 170 such as solder. The first connection terminal 151a of the temperature sensitive element 150 is connected to the first connection pad 117a, and the second connection terminal 151b is connected to the second connection pad 117b. The first connection pad 117a is connected to the third external terminal 112c through a first connection pattern 118a provided on the lower surface of the substrate 110a. Further, the third external terminal 112c serves as a ground terminal by being connected to a mounting electrode (not shown) connected to the ground, which is a reference potential on a mounting substrate such as an electronic device. Therefore, the first connection terminal 151a of the temperature sensitive element 150 is connected to the ground that is the reference potential.

  Further, since the temperature sensing element 150 is positioned in the plane of the excitation electrode 122 provided on the crystal element 120 in a plan view, the temperature sensing element 150 is made electronic by the shielding effect of the metal film of the excitation electrode 122. It protects against noise from other semiconductor parts and electronic parts such as power amplifiers that make up the equipment. Therefore, due to the shielding effect of the excitation electrode 122, it is possible to reduce the superimposition of noise on the temperature sensing element 150 and to output an accurate voltage of the temperature sensing element 150. In addition, since an accurate voltage value can be output from the temperature sensing element 150, temperature information obtained by converting the voltage output from the temperature sensing element 150 and temperature information around the actual crystal element 120 are obtained. It is possible to further reduce the difference.

  A method for bonding the temperature sensitive element 150 to the substrate 110a will be described. First, the conductive bonding material 170 is applied to the connection pads 117 by a dispenser, for example. The temperature sensitive element 150 is moved to the upper surface of the conductive bonding material 170 by a mounting nozzle (not shown) and placed on the conductive bonding material 170. The conductive bonding material 170 is melted and bonded by heating, and the lower surface of the connection terminal 151 and the side surface of the connection terminal 151 are bonded to the connection pad 117. At this time, the conductive bonding material 170 is formed with a fillet that is inclined so that the thickness gradually increases from the connection pad 117 toward the side surface of the connection terminal 151 of the temperature-sensitive element 150. Therefore, the temperature sensitive element 150 is bonded to the pair of connection pads 117.

  When the temperature sensitive element 150 is a thermistor element, as shown in FIGS. 1 and 2, one connection terminal 151 is provided at each end of the rectangular parallelepiped shape. The first connection terminal 151 a is provided on the right side surface and the top and bottom surfaces of the temperature sensing element 150. The second connection terminals 151b are provided on the left side surface and the top and bottom surfaces of the temperature sensitive element 150. The length of the long side of the temperature sensitive element 150 is 0.4 to 0.6 mm, and the length of the short side is 0.2 to 0.3 mm. The length of the thermosensitive 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. In addition, the conductive bonding material 170 contains an added solvent for adjusting the viscosity to be easily applied. The component ratio of the lead-free solder is 95 to 97.5% for tin, 2 to 4% for silver, and 0.5 to 1.0% for copper.

  The lid 130 is made of an alloy containing at least one of iron, nickel, and cobalt, for example. Such a lid 130 is for hermetically sealing the first recess K1 in a vacuum state or the first recess K1 filled with nitrogen gas or the like. Specifically, the lid 130 is placed on the first frame 110b of the package 110 in a predetermined atmosphere, and the sealing conductor pattern 119 of the first frame 110b and the bonding member 131 of the lid 130 are connected. By applying a predetermined current so as to be welded and performing seam welding, the first frame 110b is joined. The lid 130 is electrically connected to the third external terminal 112c on the lower surface of the substrate 110a via the sealing conductor pattern 119 and the third via conductor 114c. The third external terminal 112c is electrically connected to the first connection pad 117a via the first connection pattern 118. Therefore, the lid 130 is electrically connected to the connection terminal 151b of the temperature sensing element 150 and the third external terminal 112c of the substrate 110a.

  The joining member 131 is provided from the upper surface of the first frame 110b to the lower surface of the lid 130. For example, in the case of glass, the bonding member 131 is made of low-melting glass or lead oxide-based frit glass containing vanadium, which is glass that melts at 300 ° C. to 400 ° C. Glass is in the form of a paste to which a binder and a solvent are added. After being melted, the glass is solidified and joined to another member. The joining member 131 is provided by, for example, applying glass frit paste by a screen printing method and drying. Further, when the joining member 131 is printed on the upper surface of the first frame 110b, the joining member 131 is printed in an annular shape so that the joining members 131 overlap the four corners of the first frame 110b. Therefore, the thickness of the bonding member 131 at the four corners is provided to be thicker than the thickness of other portions where the bonding member 131 is provided. The composition of the lead oxide glass is composed of lead oxide, lead fluoride, titanium dioxide, niobium oxide, bismuth oxide, boron oxide, zinc oxide, ferric oxide, copper oxide and calcium oxide.

  For example, in the case of an insulating resin, the bonding member 131 is made of an epoxy resin or a polyimide resin. The thickness of the joining member 131 provided between the first frame 110b and the lid 130 is 30 to 100 μm.

  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 crystal resonator according to the embodiment of the present invention includes a rectangular substrate 110a, a first frame 110b provided on the upper surface of the substrate 110a, a second frame 110c provided on the lower surface of the substrate 110a, and a substrate 110a. In the first recess K1 formed by the first frame 110b and in the second recess K2 formed by the pair of electrode pads 111 provided on the upper surface of the substrate 110a and the substrate 110a and the second frame 110c. A pair of connection pads 117 provided on the lower surface of the substrate 110a, external terminals 112 provided at the four corners of the lower surface of the second frame 110 second recess K2, a crystal element 120 mounted on the electrode pad 111, A temperature-sensitive element 150 mounted on the connection pad 117 via a conductive bonding material 170; and a lid body 130 bonded to the upper surface of the first frame 110b. The shape of the opening of the second recess K2 is , In surface view 112, a polygonal, the corners C of the opening of the second recess K2 is viewed from the upper side, are provided so as to be positioned between the adjacent external terminal 112. By doing so, since the crystal resonator can increase the shape of the second recess K2, the area of the connection pad 117 can be increased compared to the case where the conventional crystal resonator is downsized. it can. Therefore, the amount of the conductive bonding material 170 provided on the connection pad 117 can be secured, and the bonding strength between the conductive bonding material 170 and the temperature sensitive element 150 can be improved. In addition, since such a crystal resonator can increase the shape of the opening when the second recess K2 is viewed in plan, the mounting nozzle is mounted when the temperature sensitive element 150 is mounted in the second recess K2. Since the contact with the inner wall of the second frame 110c that forms the second recess K2 is suppressed, chipping of the package 110 can be reduced.

  In the crystal resonator according to the embodiment of the present invention, the opening of the second recess K2 has an octagonal shape in plan view, so that the exposed area of the substrate 110a is larger than when the opening is circular. Since the area can be increased, the area of the connection pad 117 can be increased. Therefore, the amount of the conductive bonding material 170 provided on the connection pad 117 can be secured, and the bonding strength between the conductive bonding material 170 and the temperature sensitive element 150 can be improved.

  In the crystal resonator according to the embodiment of the present invention, the corner portion C of the opening of the second recess K2 has an arc shape in plan view, so that the crystal resonator of the present embodiment is mounted on an electronic device mounting board. Even if the package 110 is stressed when mounted on the top, the corner C is arc-shaped, so that the stress applied to the corner C is dispersed and the package 110 is cracked. Can be reduced.

  Further, the crystal resonator according to the embodiment of the present invention is sensitive to the plane of the excitation electrode 122 provided on the crystal element 120 in a plan view in a state where the crystal element 120 and the temperature sensitive element 150 are mounted on the substrate 110a. By positioning the temperature element 150, the temperature-sensitive element 150 is protected from noise from other semiconductor components such as a power amplifier constituting the electronic apparatus and electronic components by the shielding effect by the metal film of the excitation electrode 122. . Therefore, due to the shielding effect of the excitation electrode 122, it is possible to reduce the superimposition of noise on the temperature sensing element 150 and to output an accurate voltage of the temperature sensing element 150. In addition, since an accurate voltage value can be output from the temperature sensing element 150, temperature information obtained by converting the voltage output from the temperature sensing element 150 and temperature information around the actual crystal element 120 are obtained. It is possible to further reduce the difference.

  In the crystal resonator according to the embodiment of the present invention, the electrode pad 111 is provided so as to be adjacent along one side of the inner peripheral edge of the first frame 110b, and one of the connection pads 117 is viewed in plan view. It is provided so as to be positioned between the pair of electrode pads 111. By doing so, the heat transferred from the crystal element 120 is transferred to the second connection pad 117b via the substrate 110a located immediately below the electrode pad 111. Therefore, since such a crystal resonator can further shorten the heat conduction path, the temperature of the crystal element 120 and the temperature of the temperature sensing element 150 are approximated and output from the temperature sensing element 150. It becomes possible to further reduce the difference between the temperature obtained by converting the voltage and the actual temperature around the quartz crystal element 120.

  Further, the crystal resonator in the embodiment of the present invention is provided such that the second connection pattern 118b overlaps the first electrode pad 111a in plan view. By doing so, the heat transferred from the crystal element 120 is transferred from the second connection pattern 118b to the second connection pad 115b via the substrate 110a directly below the first electrode pad 111a. In such a crystal resonator, by further shortening the heat conduction path and further increasing the number of heat conduction paths, the temperature of the crystal element 120 and the temperature of the temperature-sensitive element 150 are further approximated, and the temperature sensitivity is increased. It is possible to further reduce the difference between the temperature obtained by converting the voltage output from the element 150 and the temperature around the actual crystal element 120.

  The crystal resonator according to the present embodiment includes a rectangular substrate 110a, a first frame 110b provided along the outer peripheral edge of the upper surface of the substrate 110a, an electrode pad 111 provided on the upper surface of the substrate 110a, and an electrode A wiring pattern 113 electrically connected to the pad 111 and provided on the upper surface of the substrate 110a, a crystal element 120 mounted on the electrode pad 111, and a lid 130 for hermetically sealing the crystal element 120. The wiring pattern 113 is electrically connected to the electrode pad 111 and is provided at a position overlapping the first frame 110b when viewed in plan. By doing so, the crystal resonator can suppress the generation of stray capacitance between the wiring pattern 113 and the crystal element 120. In addition, since such a crystal resonator does not impart this stray capacitance to the crystal element 120, it is possible to reduce the fluctuation of the oscillation frequency. Further, in the crystal resonator according to this embodiment, even when an external force is applied to the crystal resonator and a bending moment is generated in the long side direction of the first frame 110b, the first frame 110b is provided in addition to the substrate 110a. By being done, the location in which the 1st frame 110b is provided becomes difficult to deform | transform. Therefore, the wiring pattern 113 provided at a position overlapping the first frame 110b in plan view is less likely to be disconnected, and it is possible to prevent the oscillation frequency of the crystal resonator from being output.

  Further, the crystal resonator in the present embodiment is provided such that a part of the wiring pattern 113 extends from the electrode pad 111 toward the long side of the frame 110b and is exposed. Thus, a part of the wiring pattern 113 extends from the electrode pad 111 toward the long side direction of the first frame 110b and is exposed so as to be exposed in the first recess K1, so that the crystal When the element 120 is mounted, the conductive adhesive 140 that is about to overflow flows out along the conductive adhesive 140 and the wiring pattern 113 having good wettability, and thus flows out toward the center of the package 110. Thus, it is possible to prevent the conductive adhesive 140 from adhering to the excitation electrode 122.

  Further, in the crystal resonator according to the present embodiment, the electrode pad 111 is provided along one side of the substrate 110 a and includes a convex portion 115 provided on the upper surface of the electrode pad 111. When the quartz crystal element 120 is mounted on the electrode pad 111 via the conductive adhesive 140, even if the quartz crystal element 120 is inclined, the lead electrode 123 comes into contact with the convex portion 115. The crystal element 120 can be mounted in a stable state without being tilted downward. Further, the convex portion 115 is provided at a position overlapping with the extraction electrode 123 on the outer peripheral edge on the fixed end side of the crystal base plate 121 in plan view. By doing in this way, it can reduce that the fixed end of crystal element 120 contacts the upper surface of substrate 110a.

  In addition, the crystal resonator according to the present embodiment includes a protrusion 116 provided along a side facing one side of the substrate 110a. In this way, when an impact such as a drop is applied to the crystal resonator, the free end side of the crystal element 120 comes into contact with the protruding portion 116, so that chipping due to direct contact with the substrate 110a can be suppressed. it can.

(First modification)
Hereinafter, the crystal resonator according to the first modification of the present embodiment will be described. Note that, in the crystal resonator according to the first modification of the present embodiment, the same portions as those of the above-described crystal resonator are denoted by the same reference numerals, and description thereof will be omitted as appropriate. As shown in FIG. 7, the crystal resonator in the first modification of the present embodiment is different from that of the present embodiment in that the shape of the opening of the second recess K2 is a hexagonal shape in plan view. And different.

  The opening of the second recess K2 has a polygonal shape when viewed in plan. Further, as shown in FIG. 7B, at least one corner C of the opening of the second recess K2 is provided between the adjacent external terminals 212. That is, when viewed in a plan view, one corner C4 is provided between the second external terminal 212b and the third external terminal 212c, and the second external terminal 212b and the fourth external terminal 212d. Two corners C2 and C3 are provided between the two. Also, two corners C5 and C6 are provided between the first external terminal 212a and the third external terminal 212c, and between the first external terminal 212a and the fourth external terminal 212d. Is provided so that one corner C1 is located.

  In addition, the crystal resonator in the first modification of the present embodiment is formed so that the shape of the opening of the second recess K2 is a hexagonal shape in plan view. By doing in this way, there exists an effect similar to embodiment.

  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 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.

  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.

  In the above embodiment, the case where the first frame body 110b is integrally formed of a ceramic material in the same manner as the substrate 110a has been described. However, the first 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.

110, 210 ... Package 110a, 210a ... Substrate 110b, 210b ... First frame 110c, 210c ... Second frame 111, 211 ... Electrode pads 112, 212 ... External terminals 113, 213 ... wiring pattern 114, 214 ... via conductor 115, 215 ... projection 116, 216 ... projection 117, 217 ... connection pad 118, 218 ... connection pattern 119, 219: Conductive pattern for sealing 120: Crystal element 121 ... Crystal base plate 122 ... Electrode for excitation 123 ... Extraction electrode 130 ... Lid 131: Joining member 140 ... -Conductive adhesive 150 ... temperature sensitive element 151 ... connection terminal K1 ... first recess K2 ... second recess C ... corner

Claims (9)

A rectangular substrate;
A first frame provided on the upper surface of the substrate;
A second frame provided on the lower surface of the substrate;
A pair of electrode pads provided on an upper surface of the substrate in a first recess formed by the substrate and the first frame;
A pair of connection pads provided on the lower surface of the substrate in a second recess formed by the substrate and the second frame;
External terminals provided at the four corners of the lower surface of the second frame,
A crystal element mounted on the electrode pad;
A temperature sensitive element mounted on the connection pad via a conductive bonding material;
A lid joined to the upper surface of the first frame,
The shape of the opening of the second recess is a polygonal shape in plan view,
A crystal resonator, wherein a corner portion of the opening of the second recess is provided so as to be positioned between the adjacent external terminals in plan view. The crystal resonator according to claim 1,
A crystal resonator, wherein the opening of the second recess has an octagonal shape in plan view. The crystal resonator according to claim 1,
A crystal resonator, wherein a corner of the opening of the second recess is arcuate in plan view. The crystal resonator according to claim 1, wherein:
The temperature sensing element is positioned in a plane of an excitation electrode provided on the crystal element in plan view in a state where the crystal element and the temperature sensing element are mounted on the substrate. Crystal resonator. The crystal resonator according to any one of claims 1 to 4,
The electrode pad is provided so as to be adjacent along one side of the inner peripheral edge of the first frame,
One of the connection pads is provided so as to be positioned between the pair of electrode pads in plan view. The crystal resonator according to any one of claims 1 to 5,
The quartz crystal resonator, wherein the wiring pattern is electrically connected to the electrode pad and is provided at a position overlapping the first frame when viewed in plan. The crystal resonator according to any one of claims 1 to 6,
A part of the wiring pattern is provided so as to extend from the electrode pad toward the long side direction of the first frame and to be exposed. A crystal resonator according to any one of claims 1 to 7,
The electrode pads are provided along one side of the substrate;
A crystal resonator comprising a convex portion provided on an upper surface of the electrode pad. The crystal resonator according to claim 8, wherein
A crystal resonator comprising a protrusion provided along a side facing one side of the substrate.

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