JP6691004B2 - Crystal oscillator - Google Patents

Description

  The present invention relates to a crystal oscillator used in electronic devices and the like.

  A crystal oscillator is a device that generates a specific frequency by utilizing the piezoelectric effect of a crystal element. For example, a package including a substrate, a first frame body provided on the upper surface of the substrate to provide the first recess, and a second frame body provided on the lower surface of the substrate to provide the second recess. A crystal resonator including a crystal element mounted on an electrode pad provided on the upper surface of the substrate and a temperature sensitive element mounted on a connection pad provided on the lower surface of the substrate has been proposed (for example, , The following Patent Document 1).

JP, 2011-212340, A

  The above-described crystal unit has been reduced in size, and when a plurality of temperature-sensitive elements are mounted on a substrate, the area for mounting the temperature-sensitive elements cannot be secured, and therefore the size cannot be reduced. I was afraid. Further, even if the space for mounting the temperature-sensitive element can be secured, the connection pad for mounting the temperature-sensitive element also needs to be downsized, and the temperature-sensitive element may peel off from the connection pad. was there.

  The present invention has been made in view of the above problems, and it is possible to secure a space in which the temperature sensitive element can be mounted, and to reduce the possibility that the temperature sensitive element is peeled off from the connection pad. An object is to provide a vibrator.

  A crystal unit according to one aspect of the present invention includes a rectangular substrate, a mounting base provided along a short side of a lower surface of the substrate, a bonding terminal provided along an outer peripheral edge of the lower surface of the substrate, Bonding pads provided on both ends of the upper surface of the mounting substrate, electrode pads provided on the upper surface of the substrate, at least four or more connection pads provided on the lower surface of the substrate between the mounting substrates, and mounted on the electrode pads And a temperature sensitive element mounted on a connection pad, and a lid body for hermetically sealing the crystal element.

  A crystal unit according to one aspect of the present invention includes a rectangular substrate, a mounting base provided along a short side of a lower surface of the substrate, a bonding terminal provided along an outer peripheral edge of the lower surface of the substrate, Bonding pads provided on both ends of the upper surface of the mounting substrate, electrode pads provided on the upper surface of the substrate, at least four or more connection pads provided on the lower surface of the substrate between the mounting substrates, and mounted on the electrode pads And a temperature sensitive element mounted on the connection pad, and a lid body for hermetically sealing the crystal element. By doing so, since the long side direction of the lower surface of the substrate is opened, it is possible to arrange a plurality of temperature sensitive elements up to the outer peripheral edge of the long side of the substrate, and thus a plurality of temperature sensitive elements are arranged. It becomes possible. In addition, since the shape of the connection pad for mounting multiple temperature sensitive elements can be enlarged, the bonding strength between the temperature sensitive element and the connection pad can be improved while preventing the multiple temperature sensitive elements from coming off the connection pad. It becomes possible.

It is an exploded perspective view showing a crystal oscillator concerning this embodiment. (A) It is an AA sectional view of FIG. 1, and (b) is a BB sectional view of FIG. (A) is a perspective plan view of a package constituting the crystal unit according to the present embodiment as seen from above, and (b) is a top view of the substrate of the package constituting the crystal unit according to this embodiment as seen from above. It is a see-through plan view. (A) is a perspective plan view of a substrate of a package constituting the crystal unit according to the present embodiment as seen from the lower surface, and (b) is a perspective plan view of the crystal unit as seen from the lower surface according to the present embodiment. is there. FIG. 7A is a perspective plan view of a mounting substrate that constitutes the crystal unit according to the present embodiment as seen from above, and FIG. 7B is a perspective view of the mounting substrate that constitutes the crystal unit according to this embodiment as seen from below. It is a see-through plan view. (A) is a perspective plan view of a package constituting a crystal unit according to a modification of the present embodiment seen from above, and (b) is a package constituting a crystal unit according to a modification of the present embodiment. 3 is a perspective plan view of the substrate of FIG. (A) is a perspective plan view of a substrate of a package constituting a crystal unit according to a modification of the present embodiment as seen from the lower surface, and (b) is a bottom view of a crystal unit according to the modification of the present embodiment. It is the see-through top view seen from it.

  As shown in FIGS. 1 to 4, the crystal unit 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. Includes 150 and. The package 110 has a recess K1 surrounded by the upper surface of the substrate 110a and the inner surface of the frame 110b. Further, a second recess K2 surrounded by the lower surface of the substrate 110a and the inner side surface of the mounting substrate 160 is formed. Such a crystal oscillator is used to output a reference signal used in electronic devices and 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 115 for mounting the temperature sensitive element 150 on the lower surface. Further, a first electrode pad 111a and a second electrode pad 111b for joining the crystal element 120 are provided along one side of the substrate 110a. In addition, bonding terminals 112 are provided at the four corners of the lower surface of the substrate 110a. Further, two of the four bonding terminals 112 are electrically connected to the crystal element 120, and the remaining two of the four bonding terminals 112 are electrically connected to the temperature sensitive element 150. . Further, as shown in FIG. 4, the first bonding terminal 112a and the second bonding terminal 112b electrically connected to the crystal element 120 are provided so as to be diagonally located on the lower surface of the substrate 110a. ing. The third bonding terminal 112c and the fourth bonding terminal 112d electrically connected to the temperature sensitive element 150 are provided with the first bonding terminal 112a and the second bonding terminal 112b connected to the crystal element 120. It is provided so as to be located on a diagonal of the substrate 110a different from the diagonal.

  The substrate 110a is made of an insulating layer which is a ceramic material such as alumina ceramics or glass-ceramics. The substrate 110a may have one insulating layer or may have a plurality of insulating layers laminated. A wiring pattern 113 and a via conductor 114 for electrically connecting the electrode pad 111 provided on the upper surface and the bonding terminal 112 provided on the lower surface of the substrate 110a are provided on the surface and inside of the substrate 110a. There is. In addition, a connection pattern 115 and a conductor pattern 117 for electrically connecting the connection pad 115 provided on the lower surface and the bonding terminal 112 provided on the lower surface of the substrate 110a are provided on the surface of the substrate 110a. There is.

  The frame body 110b is arranged 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 frame 110b is made of a ceramic material such as alumina ceramics or glass-ceramics, and is integrally formed with the substrate 110a.

  The electrode pad 111 is for mounting the crystal element 120. The pair of electrode pads 111 are provided on the upper surface of the substrate 110a, and are provided adjacent to each other along one side of the substrate 110a. As shown in FIGS. 3 and 4, the electrode pad 111 is electrically connected to the bonding terminal 112 provided on the lower surface of the substrate 110a via the wiring pattern 113 provided on the upper surface of the substrate 110a and the via conductor 114. It is connected to the.

  As shown in FIG. 3, the electrode pad 111 includes a first electrode pad 111a and a second electrode pad 111b. The joint terminal 112 is composed of a first joint terminal 112a, a second joint terminal 112b, a third joint terminal 112c, and a fourth joint terminal 112d, as shown in FIG. The via conductor 114 includes a first via conductor 114a, a second via conductor 114b, and a third via conductor 114c. 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. Further, the other end of the first wiring pattern 113a is electrically connected to the first joining terminal 112a via the first via conductor 114a. Therefore, the first electrode pad 111a is electrically connected to the first bonding 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 joining terminal 112b via the second via conductor 114b.

  The bonding terminal 112 is used to electrically bond with the bonding pad 161 of the mounting substrate 160. The joining terminals 112 are provided at the four corners of the lower surface of the substrate 110a. Two of the joining terminals 112 are electrically connected to a pair of electrode pads 111 provided on the upper surface of the substrate 110a. Further, the bonding terminals 112 electrically connected to the electrode pads 111 are provided so as to be positioned diagonally on the lower surface of the substrate 110a. The third joint terminal 112c is electrically connected to the sealing conductor pattern 118 via the third via conductor 114c. In addition, the conductive bonding material 170 is provided between the bonding terminal 112 and the bonding pad 161 of the mounting substrate 160.

  The wiring pattern 113 is provided on the upper surface of the substrate 110a and is drawn out from the electrode pad 111 toward the via conductor 114 in the vicinity. The wiring pattern 113 is composed of a first wiring pattern 113a and a second 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 116, or the sealing conductor pattern 118. The via conductor 114 is provided by filling the inside of the through hole provided in the substrate 110a with a conductor. The via conductor 114 is composed of a first via conductor 114a, a second via conductor 114b, and a third via conductor 114c, as shown in FIGS.

  The connection pad 115 has a rectangular shape, and is used for mounting a first temperature sensitive element 150a and a second temperature sensitive element 150b that form a temperature sensitive element 150 described later. Further, the connection pad 115 is composed of a first connection pad 115a, a second connection pad 115b, a third connection pad 115c and a fourth connection pad 115d, as shown in FIG. The conductive bonding material 170 is also provided between the lower surface of the connection pad 115 and the connection terminal 151 of the temperature sensitive element 150.

  Here, the connection pad 115 has an example in which the substrate 110a has a long side dimension of 1.2 to 2.5 mm and a short side dimension of 1.0 to 2.0 mm in a plan view. The size of is explained. The length of the side of the connection pad 115 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. Has become. Further, the length between the first connection pad 115a and the second connection pad 115b and the length between the third connection pad 115c and the fourth connection pad 115d are 0.1 to 0.3 mm. .

  The first connection pad 115a and the fourth bonding terminal 112d are connected by the first connection pattern 116a and the first conductor pattern 117a provided on the lower surface of the substrate 110a. Further, the second connection pad 115b and the third bonding terminal 112c are connected by the second connection pattern 116b and the second conductor pattern 117b provided on the lower surface of the substrate 110a. The third connection pad 115c and the fourth bonding terminal 112d are connected by the third connection pattern 116c and the first conductor pattern 117a provided on the lower surface of the substrate 110a. The fourth connection pad 115d and the third bonding terminal 112c are connected by the fourth connection pattern 116d and the second conductor pattern 117b provided on the lower surface of the substrate 110a.

  The connection pattern 116 is provided on the lower surface of the substrate 110a, and is drawn out from the connection pad 115 toward the adjacent bonding terminal 112. Further, the connection pattern 116 is composed of a first connection pattern 116a, a second connection pattern 116b, a third connection pattern 116c, and a fourth connection pattern 116d, as shown in FIG. The length of the first connection pattern 116a and the length of the second connection pattern 116b are substantially equal to each other, and the length of the third connection pattern 116c and the length of the fourth connection pattern 116d are substantially equal to each other. Here, the substantially equal lengths mean the lengths of the first connection pattern 116a and the third connection pattern 116c provided on the lower surface of the substrate 110a and the second connection pattern 116b and the fourth connection pattern 116d provided on the lower surface of the substrate 110a. The difference with the length of 0 to 200 μm is included. As the length of the connection pattern 116, the length of a straight line passing through the center of each connection pattern 116 is measured. That is, the wiring length of the first connection pattern 116a and the wiring length of the second connection pattern 116b are substantially equal, and the wiring length of the third connection pattern 116c and the wiring length of the fourth connection pattern 116d are substantially the same. By making the lengths equal, the generated resistance values become equal, and the load resistance applied to the temperature sensitive element 150 becomes uniform, so that it is possible to stably output the voltage.

  As shown in FIGS. 3 and 4, a part of the first connection pattern 116a is provided so as to overlap with the first electrode pad 111a when seen through in a plan view. Further, by doing so, the heat transferred from the crystal element 120 is transferred from the first connection pattern 116a to the first connection pad 115a via the substrate 110a located directly below the first electrode pad 111a. Therefore, in such a crystal unit, the temperature of the crystal element 120 and the temperature of the first temperature sensitive element 150a 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 first temperature sensitive element 150a and the actual ambient temperature of the crystal element 120.

  Further, as shown in FIGS. 3 and 4, a part of the third connection pattern 116c is provided so as to overlap with the second electrode pad 111b when seen in a plan view. Further, by doing so, the heat transferred from the crystal element 120 is transferred from the third connection pattern 116c to the third connection pad 115c via the substrate 110a located immediately below the second electrode pad 111b. Therefore, in such a crystal unit, the temperature of the crystal element 120 and the temperature of the second temperature sensitive element 150b become similar by further shortening the heat conduction path and further increasing the number of heat conduction paths. The difference between the temperature obtained by converting the voltage output from the second temperature sensitive element 150b and the actual ambient temperature of the crystal element 120 can be further reduced.

  The conductor pattern 117 is for electrically connecting the adjacent connection patterns 116 and for connecting to the joining terminal 112. The conductor pattern 117 is composed of a first conductor pattern 117a and a second conductor pattern 117b. The first conductor pattern 117a electrically connects the first connection pattern 116a and the third connection pattern 116c, and the second conductor pattern 117b electrically connects the second connection pattern 116b and the fourth connection pattern 116d. is doing.

  Further, as shown in FIGS. 3 and 4, the first conductor pattern 117a is provided so as to be located between the pair of electrode pads 111 when seen through in a plan view. Further, by doing so, the heat transferred from the crystal element 120 is transmitted from the electrode pad 111 via the substrate 110a located immediately below, from the first conductor pattern 117a via the first connection pattern 116a and the third connection pattern 116c. , The first connection pad 115a and the third connection pad 115c. Therefore, in such a crystal unit, since the heat conduction path can be further shortened, the temperature of the crystal element 120 and the temperatures of the first temperature sensitive element 150a and the second temperature sensitive element 150b are close to each other. It is possible to further reduce the difference between the temperature obtained by converting the voltages output from the first temperature sensitive element 150a and the second temperature sensitive element 150b and the actual ambient temperature of the crystal element 120. Become.

  The sealing conductor pattern 118 plays a role of improving the wettability of the joining member 131 when joining the lid 130 and the joining member 131. As shown in FIGS. 3 and 4, the sealing conductor pattern 118 is electrically connected to the third joining terminal 112c via the third via conductor 114c. The sealing conductor pattern 118 is formed to have a thickness of, for example, 10 to 25 μm by sequentially performing nickel plating and gold plating on the surface of the conductor pattern made of, for example, tungsten or molybdenum so as to surround the upper surface of the frame body 110b in an annular shape. Has been done.

  Here, a method for manufacturing the substrate 110a will be described. When the substrate 110a is made of alumina ceramics, first, a plurality of ceramic green sheets obtained by adding and mixing an appropriate organic solvent or the like with a predetermined ceramic material powder is prepared. Further, a predetermined conductor paste is applied to the surface of the ceramic green sheet or a through hole which has been preliminarily formed by punching the ceramic green sheet by screen printing or the like well known in the art. Further, the green sheets laminated and press-molded are fired at a high temperature. Finally, nickel plating is performed on a predetermined portion of the conductor pattern, specifically, a portion to be the electrode pad 111, the bonding terminal 112, the wiring pattern 113, the via conductor 114, the connection pad 115, the connection pattern 116, and the sealing conductor pattern 118. It is also manufactured by applying gold plating, silver palladium, or the like. The conductor paste is made of, for example, a sintered body of metal powder such as tungsten, molybdenum, copper, silver or silver palladium.

  The mounting base 160 is bonded along both ends of the lower surface of the substrate 110a to form the second recess K2 on the lower surface of the substrate 110a. The mounting base 160 is made of, for example, an insulating substrate made of glass epoxy resin or the like, and is bonded to the lower surface of the substrate 110a via a conductive bonding material 170. As shown in FIG. 5, a conductor portion 164 for electrically connecting the bonding pad 161 provided on the upper surface and the external terminal 162 provided on the lower surface of the mounting substrate 160 is provided inside the mounting substrate 160. It is provided. The mounting base 160 is composed of a first mounting base 160a and a second mounting base 160b. Bonding pads 161 are provided on both ends of the upper surface of the mounting substrate 160, and external terminals 162 are provided on both ends of the lower surface. Further, two of the four external terminals 162 are electrically connected to the crystal element 120 and used as input / output terminals of the crystal element 120. Further, two of the four external terminals 162 are electrically connected to the temperature sensitive element 150. Further, the first external terminal 162 a and the second external terminal 162 b electrically connected to the crystal element 120 are provided so as to be positioned diagonally on the lower surface of the mounting substrate 160. The third external terminal 162c and the fourth external terminal 162d electrically connected to the first temperature sensitive element 150a and the second temperature sensitive element 150b are the first external terminal 162a and the first external terminal 162a connected to the crystal element 120, respectively. The second external terminals 162b are provided so as to be located on a diagonal of the mounting substrate 160 different from the diagonal on which the second external terminals 162b are provided.

  The bonding pad 161 is for electrically bonding to the bonding terminal 112 of the substrate 110a via the conductive bonding material 170. As shown in FIG. 5A, the bonding pad 161 is composed of a first bonding pad 161a, a second bonding pad 161b, a third bonding pad 161c and a fourth bonding pad 161d.

  The external terminal 162 is for mounting on a mounting board such as an electronic device. The external terminal 162 is provided on the lower surface of the mounting substrate 160. Two of the external terminals 162 are electrically connected to a pair of electrode pads 111 provided on the upper surface of the substrate 110a. The remaining two terminals of the external terminals 162 are electrically connected to the pair of connection pads 115 provided on the lower surface of the substrate 110a. In addition, the third external terminal 162c is connected to a mounting pad that is connected to a ground potential that is a reference potential on a mounting substrate of an electronic device or the like. As a result, the lid 130 joined to the sealing conductor pattern 118 is connected to the third external terminal 162c having the ground potential. Therefore, the shielding property of the lid 130 in the first recess K1 is improved.

  Further, as shown in FIG. 5B, the external terminal 162 includes a first external terminal 162a, a second external terminal 162b, a third external terminal 162c, and a fourth external terminal 162d. The conductor portion 164 includes a first conductor portion 164a, a second conductor portion 164b, a third conductor portion 164c, and a fourth conductor portion 164d. The first bonding pad 161a is electrically connected to the first external terminal 162a via the first conductor portion 164a, and the second bonding pad 161b is connected to the second external terminal 162b via the second conductor portion 164b. It is electrically connected. The third bonding pad 161c is electrically connected to the third external terminal 162c via the third conductor portion 164c, and the fourth bonding pad 161d is connected to the fourth external terminal 162d via the fourth conductor portion 164d. It is electrically connected.

  The conductor portion 164 is for electrically connecting the bonding pad 161 on the upper surface of the mounting substrate 160 and the external terminal 162 on the lower surface. The conductor portion 164 is formed by forming through holes at the four corners of the mounting substrate 160, forming a conductive member on the inner wall surface of the through hole, closing the upper surface with the bonding pads 161, and closing the lower surface with the external terminals 162. There is.

  The second recess K2 is in a state in which the long side direction of the substrate 110a is open. By doing so, since the temperature sensitive element 150 can be arranged near the outer peripheral edge on the long side of the substrate 110a, it is possible to secure a space for mounting the plurality of temperature sensitive elements 150. Further, before applying the insulating resin 180, it is possible to confirm the bonding state between the first temperature sensitive element 150a and the second temperature sensitive element 150b and the connection pad 115 of the substrate 110a. Further, since the opening of the second recess K2 is formed, the insulating resin is attached to the mounting base 160 in order to prevent the nozzle for applying the conductive adhesive 180 from contacting the mounting base 160. Since it can be applied to the temperature sensitive element 150 without the need, the productivity can be improved.

 The opening of the second recess K2 has a rectangular shape in plan view. Here, when the substrate 110a has a long side dimension of 1.2 to 2.5 mm and a short side dimension of 1.0 to 2.0 mm in a plan view, the second concave portion is taken as an example. The size of the opening of K2 will be described. The long side of the second recess K2 has a length of 0.6 to 1.2 mm, and the short side has a length of 0.3 to 1.0 mm.

  A method of joining the mounting base 160 to the substrate 110a will be described. First, the conductive bonding material 170 is applied on the first bonding pad 161a, the second bonding pad 161b, the third bonding pad 161c, and the fourth bonding pad 161d by, for example, a dispenser and screen printing. The substrate 110a is transported such that the bonding terminals 112 of the substrate 110a are positioned on the conductive bonding material 170 applied on the bonding pads 161 of the mounting substrate 160, and is placed on the conductive bonding material 170. As a result, the bonding terminal 112 of the substrate 110 a is bonded to the bonding pad 161 by heating and melting the conductive bonding material 170. That is, the first bonding terminal 112a of the substrate 110a is bonded to the first bonding pad 161a, and the second bonding terminal 112b of the substrate 110a is bonded to the second bonding pad 161b. In addition, the third bonding terminal 112c of the substrate 110a is bonded to the third bonding pad 161c, and the fourth bonding terminal 112d of the substrate 110a is bonded to the fourth bonding pad 161d.

  In addition, the bonding terminal 112 of the substrate 110a and the bonding pad 161 of the mounting base 160 are bonded via the conductive bonding material 170, so that the substrate 110a and the mounting base 160 are connected as shown in FIG. 2B. A gap H, which is the sum of the thickness of the conductive joint material 170 and the thickness of the joint terminal 112 and the joint pad 161, is provided between them, and the gap H is filled with the insulating resin 180 that covers the temperature-sensitive element 150. It is provided. As a result, if the crystal unit of this embodiment is mounted on a mounting board of an electronic device or the like, other electronic components such as power amplifiers mounted on the mounting board generate heat and the heat is generated. Even if the heat is transferred to the second recess K2 via the mounting substrate, the heat is transferred from the insulating resin 180 in the second recess K2 to the insulating resin 180 provided in the gap H. Finally, since the insulating resin 180 is exposed to the outside, heat is released into the atmosphere. By doing so, the influence of heat on the temperature-sensitive element 150 mounted in the second recess K2 can be reduced. Therefore, such a crystal oscillator can reduce the difference between the temperature obtained by converting the voltage output from the temperature sensitive element 150 and the actual temperature around the crystal element 120.

  Further, since the insulating resin 180 is provided in such a gap portion H, the temperature sensitive element 150 is reliably fixed by the insulating resin 180. Therefore, it is possible to reduce the peeling of the temperature sensitive element 150 from the substrate 110a.

  Here, a method of manufacturing the mounting substrate 160 will be described. When the mounting substrate 160 is a glass epoxy resin, it is manufactured by impregnating a base material made of glass fibers with an epoxy resin precursor and thermally curing the epoxy resin precursor at a predetermined temperature. Further, the predetermined portion of the conductor pattern, specifically, the bonding pad 161 and the external terminal 162, for example, a copper foil processed into a predetermined shape is transferred onto a resin sheet made of glass epoxy resin, and the copper foil is transferred. It is formed by laminating the resin sheets thus obtained and adhering them with an adhesive. The conductor portion 163 is formed by depositing a metal on the inner surface of the through hole formed in the resin sheet by printing a conductor paste or by plating, or by filling the through hole with a metal. Such a conductor portion 163 is formed, for example, by integrating a metal foil or a metal pillar by resin molding or by applying the metal foil or metal pillar by a sputtering method, a vapor deposition method, or the like.

  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 piezoelectric effect.

  Further, as shown in FIGS. 1 and 2, the crystal element 120 has a structure in which the excitation electrode 122 and the extraction electrode 123 are adhered to the upper surface and the lower surface of the crystal element 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 crystal 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 blank 121. The extraction electrode 123 has a first extraction electrode 123a on the upper surface and a second extraction electrode 123b on the lower surface. The first extraction electrode 123a is extracted from the first excitation electrode 122a and is provided so as to extend toward one side of the quartz crystal plate 121. The second extraction electrode 123b is extracted from the second excitation electrode 122b, and is provided so as to extend toward one side of the crystal blank 121. That is, the extraction electrode 123 is provided in a shape along the long side or the short side of the crystal blank 121. Further, in the present embodiment, one end of the crystal element 120 connected to the first electrode pad 111a and the second electrode pad 111b is a fixed end connected to the upper surface of the substrate 110a, and the other end is between the upper surface of the substrate 110a. The crystal element 120 is fixed on the substrate 110a with a cantilevered support structure having a free end.

  Here, the operation of the crystal element 120 will be described. In the crystal element 120, when an alternating voltage from the outside is applied to the crystal element plate 121 from the extraction electrode 123 via the excitation electrode 122, the crystal element plate 121 is excited in a predetermined vibration mode and frequency. ing.

  Here, a method for manufacturing the crystal element 120 will be described. First, the crystal element 120 is cut from an artificial lens at a predetermined cut angle to reduce the thickness of the outer periphery of the crystal element plate 121, and the central portion of the crystal element plate 121 becomes thicker than the outer peripheral portion of the crystal element plate 121. Bevel processing is performed as described above. Then, the crystal element 120 is manufactured by depositing a metal film on both main surfaces of the crystal element plate 121 by a photolithography technique, an evaporation technique or a sputtering technique to form an excitation electrode 122 and an extraction electrode 123. To be done.

  A method of bonding the crystal element 120 to the substrate 110a will be described. First, the conductive adhesive 140 is applied to the first electrode pad 111a and the second electrode pad 111b by, for example, a dispenser. The crystal element 120 is conveyed on the conductive adhesive 140 and placed on the conductive adhesive 140. Then, the conductive adhesive 140 is cured and shrunk by heating and curing. The crystal element 120 is bonded to the electrode pad 111. That is, the first extraction electrode 123a of the crystal element 120 is joined to the second electrode pad 111b, and the second extraction electrode 123b is joined to the first electrode pad 111a. As a result, the first bonding terminal 112a and the second bonding terminal 112b are electrically connected to the crystal element 120, and the crystal element 120 is electrically connected to the first external terminal 161a and the second external terminal 161b of the mounting substrate 160. It

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

  As the temperature sensitive element 150, a thermistor, a platinum resistance temperature detector or a diode is used. In the case of a thermistor element, the temperature sensitive element 150 has a rectangular parallelepiped shape and has connection terminals 151 provided at both ends. The temperature sensitive element 150 is composed of a first temperature sensitive element 150a and a second temperature sensitive element 150b. The temperature-sensitive element 150 has a remarkable change in electric resistance due to a temperature change, and the voltage changes due to the change in the resistance value. Temperature information can be obtained from the applied voltage. In the temperature-sensitive element 150, a voltage between connection terminals 151, which will be described later, is output to the outside of the crystal unit via the third external terminal 162c and the fourth external terminal 162d of the mounting substrate 160. Temperature information can be obtained by converting the voltage output from a main IC (not shown) such as the above into temperature. Such a temperature-sensitive element 150 is arranged near the crystal unit, and the voltage for driving the crystal unit is controlled by the main IC according to the temperature information of the crystal unit obtained by this, so-called temperature compensation. You can

  When the temperature sensitive element 150 is a thermistor element, the first temperature sensitive element 150a and the second temperature sensitive element 150b are connected in parallel. By doing so, a resistance value with a narrow deviation can be obtained without deteriorating the thermistor characteristics, and the B constant, which is a physical property value indicating the sensitivity (rate of change in resistance value) of the thermistor element with respect to temperature change, can be obtained. The decrease can be suppressed.

  When a platinum resistance temperature detector is used, the temperature sensing element 150 is provided with a platinum electrode by depositing platinum on the center of a rectangular parallelepiped ceramic plate. Further, connection terminals 151 are provided on 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 sensitive element 150 has a structure in which a semiconductor element is mounted on the upper surface of a semiconductor element substrate and the upper surfaces of the semiconductor element and the semiconductor element substrate are covered with an insulating resin. . Connection terminals 151 serving as an anode terminal and a cathode terminal are provided on the lower surface and the side surface of the semiconductor element substrate. The temperature sensitive element 150 has a forward characteristic in which a current flows from the anode terminal to the cathode terminal, but almost no current flows from the cathode terminal to the anode terminal. The forward characteristic of the temperature sensitive element largely changes depending on the temperature. Voltage information can be obtained by measuring the forward voltage with a constant current applied to the temperature sensitive element. By converting from the voltage information, the temperature information of the crystal element can be obtained. The diode has a linear relationship between voltage and temperature. The voltage between the cathode terminal and the anode terminal of the connection terminal 151 is output to the outside of the crystal unit via the third external terminal 162c and the fourth external terminal 162d.

  As shown in FIG. 2, the temperature sensitive element 150 is mounted on the connection pad 115 provided on the lower surface of the substrate 110a via a conductive bonding material 170 such as solder. Further, the first connection terminal 151a of the first temperature sensitive element 150a is connected to the first connection pad 115a, and the second connection terminal 151b is connected to the second connection pad 115b. The third connection terminal 151c of the second temperature sensitive element 150b is connected to the third connection pad 115c, and the fourth connection terminal 151d is connected to the fourth connection pad 115d. The second connection pad 115b and the fourth connection pad 115d are connected to each other via the second connection pattern 116b, the fourth connection pattern 116d, the second conductor pattern 117b and the bonding pad 161c of the mounting substrate 160, which are provided on the lower surface of the substrate 110a. Three external terminals 162c are connected. Further, the third external terminal 162c plays a role of a ground terminal by being connected to a mounting pad which is connected to a ground which is a reference potential on a mounting board of an electronic device or the like. Therefore, the second connection terminal 151b of the first temperature sensitive element 150a and the fourth connection terminal 151d of the second temperature sensitive element 150b are connected to the ground, which is the reference potential.

  Further, since a part of the plurality of temperature sensitive elements 150 is located in the plane of the excitation electrode 122 provided in the crystal element 120 in plan view, the shielding effect of the metal film of the excitation electrode 122 is provided. The temperature sensitive element 150 is protected from noise from other semiconductor parts such as a power amplifier and electronic parts which constitute an electronic device. 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 output the accurate voltage of the temperature sensing element 150. Further, since an accurate voltage value can be output from the temperature sensitive element 150, temperature information obtained by converting the voltage output from the temperature sensitive element 150 and actual temperature information around the crystal element 120. It is possible to further reduce the difference between and.

  A method of joining the temperature sensitive element 150 to the substrate 110a will be described. First, the conductive bonding material 170 is applied to the connection pad 115 by, for example, a dispenser. The temperature sensitive element 150 is placed on the conductive bonding material 170. Then, the conductive bonding material 170 is melt-bonded by heating. Therefore, the plurality of temperature sensitive elements 150 are bonded to the corresponding connection pads 115, respectively.

  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 151a and the third connection terminal 151c are provided on the right side surface and the upper and lower surfaces of the first temperature sensitive element 150a and the second temperature sensitive element 150b. The second connection terminal 151b and the fourth connection terminal 151d are provided on the left side surface and the upper and lower surfaces of the first temperature sensitive element 150a and the second temperature sensitive element 150b. The length of the long side of such a 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 temperature sensitive element 150 in the thickness direction is 0.1 to 0.3 mm.

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

  The insulating resin 180 prevents the solder or the like used when mounting it on a mounting substrate of an electronic device or the like from attaching to the temperature sensitive element 150, and connects the connection terminal 151 of the temperature sensitive element 150 and the mounting base 160b to the outside. This is to reduce short circuit with the terminal 162. The insulating resin 180 covers the temperature sensitive element 150 and is provided in the gap H between the temperature sensitive element 150 and the substrate 110a and between the mounting base 160 and the substrate 110a.

  Next, in the method of applying the insulating resin 180, the uncured insulating resin 180 is applied between the temperature sensitive element 150 and the substrate 110a and between the mounting substrate 160 and the substrate through the opening of the second recess K2. Filled in between. The filling is performed by, for example, a dispenser. By doing so, the reliability of the electrical connection between the bonding pad 161 and the bonding terminal 112 can be further improved. In addition, since the insulating resin 180 is provided around the bonding pad 161, the insulating resin 180 is also provided around the conductive bonding material 170 provided between the bonding pad 161 and the bonding terminal 112. Therefore, it is possible to reduce a short circuit with another electronic component mounted on the electronic device or the like due to adhesion of solder or the like.

  The lid 130 is made of, for example, an alloy containing at least one of iron, nickel and cobalt. The 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 frame 110b of the package 110 in a predetermined atmosphere, and the sealing conductor pattern 118 of the frame 110b and the joining member 131 of the lid 130 are welded together. A predetermined current is applied to the seam to perform seam welding, thereby joining the frame body 110b. The lid 130 is electrically connected to the third external terminal 162c on the lower surface of the mounting substrate 160 via the sealing conductor pattern 118, the third via conductor 114c, and the third conductor portion 164c. The third external terminal 162c is electrically connected to the second connection pad 115b and the fourth connection pad 115d via the conductive bonding material 170. Therefore, the lid 130 is electrically connected to the third external terminal 162c of the package 110.

  The joining member 131 is provided at a position of the lid 130 facing the sealing conductor pattern 118 provided on the upper surface of the frame 110b of the package 110. The joining member 131 is provided by, for example, silver solder or gold tin. In the case of silver wax, its thickness is 10 to 20 μm. For example, the component ratio is 72 to 85% of silver and 15 to 28% of copper. In the case of gold tin, its thickness is 10 to 40 μm. For example, the component ratio of gold is 78 to 82% and tin is 18 to 22%.

  The crystal unit according to the present embodiment includes a rectangular substrate 110a, a pair of mounting bases 160 provided along the shorter sides of the lower surface of the substrate 110a, and bonding provided along the outer peripheral edge of the lower surface of the substrate 110a. Terminals 112, bonding pads 161 provided on both ends of the upper surface of the mounting base 160, electrode pads 111 provided on the upper surface of the substrate 110a, and at least four terminals provided on the lower surface of the substrate 110a between the mounting bases 160. The connection pad 115, the crystal element 120 mounted on the electrode pad 111, at least two or more temperature sensitive elements 150 mounted on the connection pad 115, and the lid 130 for hermetically sealing the crystal element 120. And are equipped with. By doing so, since the long side direction of the lower surface of the substrate 110a is opened, it is possible to arrange the plurality of temperature sensitive elements 150 up to the outer peripheral edge of the long side of the substrate 110a, and thus the plurality of temperature sensitive elements. It becomes possible to arrange 150. Further, since the shape of the connection pad 115 for mounting the plurality of temperature sensitive elements 150 can be made large, the plurality of temperature sensitive elements 150 can be prevented from coming off the connection pad 115, and the temperature sensitive elements 150 and the connection pads can be suppressed. It is possible to improve the bonding strength of 115.

  Further, in the crystal unit according to the present embodiment, the mounting base 160 is formed of a glass epoxy substrate. By doing so, the base material of the mounting base 160 and the base material of the mounting substrate (not shown) that constitutes the electronic device or the like are made of the same resin material, so that the difference in the coefficient of thermal expansion is further reduced. can do. Therefore, even if the mounting board is deformed by heating, the stress due to the deformation is relieved by the presence of the mounting base 160, and as a result, the stress applied to the solder is relieved. Such a crystal resonator can reduce the occurrence of peeling from a mounting substrate of an electronic device or the like.

  Further, the crystal unit of the present embodiment includes an insulating resin 180 provided so as to cover the temperature sensitive element 150. In such a crystal unit, since the temperature sensitive element is protected by the insulating resin 180, it is possible to prevent metal scraps from adhering to the temperature sensitive element 150 and short-circuiting the connection terminals 151. .

  Further, in the crystal unit according to the present embodiment, the insulating resin 180 is provided in the gap H. When such a crystal unit is mounted on a mounting board of an electronic device or the like, other electronic components such as a power amplifier mounted on the mounting board generate heat, and the heat is transmitted through the mounting board to the first side. Even if the heat is transferred to the second recess K2, the heat is transferred from the insulating resin 180 in the second recess K2 to the insulating resin 180 provided in the gap H. Next, the heat is released to the atmosphere because the insulating resin 180 provided in the gap H is exposed to the outside. By doing so, the influence of heat on the temperature-sensitive element 150 mounted in the second recess K2 can be reduced. Therefore, such a crystal oscillator can reduce the difference between the temperature obtained by converting the voltage output from the temperature sensitive element 150 and the actual temperature around the crystal element 120.

  Further, in the crystal unit according to the present embodiment, when the crystal element 120 and the temperature sensitive element 150 are mounted on the substrate 110a, the crystal element is sensed in the plane of the excitation electrode 122 provided on the crystal element 120 in a plan view. By locating the temperature element 150, the temperature sensing element 150 is protected from noise from other semiconductor components such as power amplifiers constituting electronic equipment and electronic components by the shielding effect of 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 output the accurate voltage of the temperature sensing element 150. Further, since an accurate voltage value can be output from the temperature sensitive element 150, temperature information obtained by converting the voltage output from the temperature sensitive element 150 and actual temperature information around the crystal element 120. It is possible to further reduce the difference between and.

  Further, the crystal unit according to the present embodiment includes a connection pattern 116 that is provided on the lower surface of the substrate 110a and is electrically connected to the connection pad 115, and a part of the connection pattern 116 is an electrode when seen through a plane. It is provided so as to overlap with the pad 111. By doing so, the heat transmitted from the crystal element 120 is transferred from the first connection pattern 116a and the third connection pattern 116c to the first connection pattern 116a and the third connection pattern 116c via the substrate 110a immediately below the first electrode pad 111a and the second electrode pad 111b. It is transmitted to the connection pad 115a and the third connection pad 115c. In such a crystal unit, the temperature of the crystal element 120 and the temperatures of the first temperature sensitive element 150a and the second temperature sensitive element 150b are controlled by further shortening the heat conduction path and further increasing the number of heat conduction paths. By further approximating, it becomes possible to further reduce the difference between the temperature obtained by converting the voltage output from the temperature sensitive element 150 and the actual ambient temperature of the crystal element 120.

  Further, the crystal unit according to the present embodiment is provided on the lower surface of the substrate 110a and electrically connected to the connection pads 115, and the lower surface of the substrate 110a is electrically connected to the connection pattern 116. And the electrode pads 111 are provided so as to be adjacent to each other along one side of the inner peripheral edge of the frame body 110b, and one of the conductor patterns 116 is seen through in a plan view to form a pair of electrode pads 111. It is provided so as to be located between. By doing so, the heat transferred from the crystal element 120 is transferred from the electrode pad 111 to the first conductor pattern 116a via the substrate 110a located immediately below, and from the first conductor pattern 116a to the first connection pattern 116a and the third connection pattern 116a. It is transmitted to the first connection pad 115a and the third connection pad 115c via the connection pattern 116c. Therefore, in such a crystal unit, since the heat conduction path can be further shortened, the temperature of the crystal element 120 and the temperatures of the first temperature sensitive element 150a and the second temperature sensitive element 150b are close to each other. It is possible to further reduce the difference between the temperature obtained by converting the voltage output from the temperature sensitive element 150 and the actual ambient temperature of the crystal element 120.

(Modification)
Hereinafter, a crystal device according to a modified example of this embodiment will be described. In addition, among the crystal devices in the modification of the present embodiment, the same parts as those in the above-described crystal device are designated by the same reference numerals, and the description thereof will be appropriately omitted. As shown in FIGS. 6 to 7, in the crystal device according to the modified example of the present embodiment, the connection pad 215 of the substrate 210a is arranged such that the long side of the temperature sensitive element 150 is parallel to the short side of the substrate 210a. The present embodiment is different from the present embodiment in that it is implemented in.

  The connection pad 215 has a rectangular shape and is provided near the center of the lower surface of the substrate 210a. As shown in FIG. 7, the connection pads 215 are provided adjacent to each other such that the long sides of the connection pads 215 and the short sides of the substrate 210a are parallel to each other. The connection pad 215 includes a first connection pad 215a, a second connection pad 215b, a third connection pad 215c and a fourth connection pad 215d.

  As shown in FIG. 7B, the connection patterns 216 are provided on the lower surface of the substrate 210a and are respectively drawn from the connection pads 215 toward the conductor patterns 217 in the vicinity. The first conductor pattern 217a is provided so as to overlap the first wiring pattern 213a. By doing so, the heat transferred from the crystal element 120 is transferred from the first electrode pad 211a to the first wiring pattern 213a, and from the first conductor pattern 217a via the substrate 210a immediately below the first wiring pattern 213a. It is transmitted to the first connection pattern 216a and the third connection pattern 216c, and is transmitted from the first connection pattern 216a and the third connection pattern 216c to the first connection pad 215a and the third connection pad 215c. Therefore, in such a crystal unit, since the heat conduction path can be further shortened, the temperature of the crystal element 120 and the temperature of the temperature sensitive element 150 become close to each other, and the temperature is output from the temperature sensitive element 150. It is possible to further reduce the difference between the temperature obtained by converting the voltage and the actual ambient temperature of the crystal element 120.

  The temperature sensitive element 150 is mounted on the lower surface of the substrate 210a such that the long side of the temperature sensitive element 150 and the short side of the substrate 210a are parallel to each other. By doing so, the first bonding terminal 212a electrically connected to the crystal element 120 can be made longer in the interval between the first connection pad 215a and the third connection pad 212c, and the crystal element 120 and The second connection terminal 212b that is electrically connected can have a longer distance between the second connection pad 215b and the fourth connection pad 215d, so that the first temperature sensitive element 150a and the second temperature sensitive element 150b can be connected to each other. Even if the conductive bonding material 170 bonded together overflows, it is possible to prevent the conductive bonding material 170 from adhering to the second bonding terminal 212b. Therefore, it is possible to reduce the short circuit between the temperature sensitive element 150 and the bonding terminal 212 electrically connected to the crystal element 120.

  Note that the present invention is not limited to this embodiment, and various modifications and improvements can be made without departing from the scope of the present invention. In the above embodiment, the crystal element is the case of using the AT crystal element. However, a tuning fork type bent crystal having a base portion and two flat plate-shaped vibrating arm portions extending in the same direction from the side surface of the base portion. An element may be used.

  In the above embodiment, the case where the frame body 110b is integrally formed of the ceramic material similarly to the substrate 110a has been described, but the frame body 110b may be made of metal. In this case, the frame body is joined to the conductor film of the substrate through a brazing material such as silver-copper.

  Although the case where the frame 110b is provided on the upper surface of the substrate 110a has been described in the above embodiment, the frame 110b may not be provided. In this case, the lid body may be configured by a rectangular sealing base portion and a sealing frame portion provided along the outer peripheral edge of the lower surface of the sealing base portion. In such a lid, an accommodation space is formed by the lower surface of the sealing base and the inner side surface of the sealing frame. The sealing frame portion is provided along the outer edge of the lower surface of the sealing base portion. The sealing base portion and the sealing frame portion are made of, for example, an alloy containing at least one of iron, nickel, and cobalt, and are integrally formed. Such a sealing lid is for hermetically sealing the storage space in a vacuum state or the storage space filled with nitrogen gas or the like. Specifically, the lid is placed on the upper surface of a flat substrate in a predetermined atmosphere, and heat is applied to the joining member provided between the upper surface of the substrate and the lower surface of the sealing frame portion. By doing so, fusion bonding is performed.

110, 210 ... Package 110a, 210a ... Substrate 110b, 210b ... Frame body 111, 211 ... Electrode pad 112, 212 ... Joining terminal 113, 213 ... Wiring pattern 114, 214 ... ..Via conductors 115, 215 ... Connection pads 116, 216 ... Connection patterns 117, 217 ... Conductor patterns 118, 218 ... Sealing conductor patterns 120 ... Crystal elements 121 ... Crystals Base plate 122 ... Excitation electrode 123 ... Extraction electrode 130 ... Lid body 131 ... Joining member 140 ... Conductive adhesive 150 ... Temperature sensitive element 151 ... Connection terminal 160. ..Mounting substrate 161 ... Bonding pad 162 ... External terminal 164 ... Conductor part 180 ... Insulating resin K1 ... First recess K2. And second recess H ··· gap

Claims (6)

A rectangular substrate,
A mounting substrate provided along the short side of the lower surface of the substrate,
Joining terminals provided along the outer peripheral edge of the lower surface of the substrate,
A bonding pad provided at both ends of the upper surface of the mounting base member,
An electrode pad provided on the upper surface of the substrate,
At least four or more connection pads provided on the lower surface of the substrate between the mounting bases,
A crystal element mounted on the electrode pad,
At least two or more temperature sensitive elements mounted on the connection pad,
A lid for hermetically sealing the crystal element,
A connection pattern provided on the lower surface of the substrate and electrically connected to the connection pad,
A crystal resonator, wherein a part of the connection pattern is provided so as to overlap with the electrode pad when seen in a plan view . The crystal unit according to claim 1,
A crystal unit, wherein the mounting substrate is formed of a glass epoxy substrate. The crystal resonator according to claim 1 or 2, wherein
A crystal resonator comprising an insulating resin provided so as to cover the temperature sensitive element. The crystal resonator according to claim 3,
A gap provided between the substrate and the mounting base,
A crystal resonator, wherein the insulating resin is provided in the gap. The crystal resonator according to claim 1, wherein
A part of the temperature-sensitive element is located in the plane of the excitation electrode provided on the crystal element in a plan view with the crystal element and the temperature-sensitive element mounted on the substrate. Crystal oscillator characterized by. The crystal unit according to claim 5 ,
A frame body arranged along the outer peripheral edge of the upper surface of the substrate,
A connection pattern provided on the lower surface of the substrate and electrically connected to the connection pad,
A conductor pattern provided on the lower surface of the substrate and electrically connected to the connection pattern,
The electrode pad is provided so as to be adjacent along one side of the inner peripheral edge of the frame body,
Crystal oscillator, characterized in that one of said conductor pattern is provided so as to be positioned between the electrode pads of a pair in a plan perspective.

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