JP2015211328A - Crystal oscillator - Google Patents

Abstract

The present invention provides a crystal resonator capable of improving the bonding strength between a conductive bonding material and a temperature sensitive element. A quartz resonator includes a rectangular substrate 110a, a first frame 110b provided on an upper surface of the substrate 110a, a second frame 110c provided on a lower surface of the substrate 110a, and a first frame. A pair of electrode pads 111 provided on the upper surface of the substrate 110a in 110b, a pair of connection pads 115 provided on the lower surface of the substrate 110a in the second frame 110c, and the connection pads 115; A pair of mounting pads 116 provided on the lower surface of the substrate 110a, a crystal element 120 mounted on the electrode pad 111, a temperature sensing element 150 mounted on the connection pad 115 and the mounting pad 116 with a conductive bonding material 170, A lid 130 joined to the upper surface of the first frame 110b, and the mounting pad 116 expands as it approaches the inner peripheral edge of the second frame 110c in plan view. It is provided. [Selection] Figure 2

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 2011-2111340 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. Such crystal resonators are being miniaturized and the area of the connection pad is reduced, so that the amount of the conductive bonding material provided on the connection pad is reduced, and the conductive bonding material and the temperature sensing element are reduced. There was a possibility that the bonding strength with the lowering.

  This invention is made | formed in view of the said subject, and makes it a subject to provide the crystal oscillator which can improve the joint strength of an electroconductive joining material and a temperature sensing element.

  A crystal resonator according to an 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 a substrate in the first frame. A pair of electrode pads provided on the upper surface of the substrate, a pair of connection pads provided on the lower surface of the substrate in the second frame, and a pair of mounting pads provided on the lower surface of the substrate electrically connected to the connection pads A mounting pad comprising: a crystal element mounted on the electrode pad; a temperature sensing element mounted on the connection pad and the mounting pad with a conductive bonding material; and a lid bonded to the upper surface of the first frame body. However, it is provided so that it may spread as it approaches the inner peripheral edge part of a 2nd frame part in planar view.

  A crystal resonator according to an 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 a substrate in the first frame. A pair of electrode pads provided on the upper surface of the substrate, a pair of connection pads provided on the lower surface of the substrate in the second frame, and a pair of mounting pads provided on the lower surface of the substrate electrically connected to the connection pads A mounting pad comprising: a crystal element mounted on the electrode pad; a temperature sensing element mounted on the connection pad and the mounting pad with a conductive bonding material; and a lid bonded to the upper surface of the first frame body. However, it is provided so that it may spread as it approaches the inner peripheral edge part of a 2nd frame part in planar view. In this way, the conductive bonding material for bonding the temperature sensing element is provided not only on the connection pad but also on the mounting pad, so that the conductive bonding material is connected to the connection terminal of the temperature sensing element from the mounting pad. A fillet having an inclination that gradually increases the thickness of the conductive bonding material toward the side surface is formed, and along the shape of the mounting pad that is provided so as to spread toward the inner peripheral edge of the second frame portion. Therefore, the conductive bonding material is also spread so that the amount of the conductive bonding material can be secured, and the bonding strength between the conductive bonding material and the temperature sensitive element can be improved.

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 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 package which comprises the crystal oscillator concerning the 1st modification of this embodiment from the upper surface, (b) is the crystal oscillator concerning the 1st modification of this embodiment. It is the plane perspective view which looked at the substrate of the package which constitutes from the upper surface. (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. It is the top view which looked at the crystal oscillator concerning the 2nd modification of this embodiment from the lower surface. (A) is the plane perspective view which looked at the package which comprises the crystal resonator which concerns on the 2nd modification of this embodiment from the upper surface, (b) is the crystal resonator which concerns on the 2nd modification of this embodiment. It is the plane perspective view which looked at the substrate of the package which constitutes from the upper surface. (A) is the plane perspective view which looked at the substrate of the package which constitutes the crystal oscillator concerning the 2nd modification of this embodiment from the lower surface, and (b) is the crystal concerning the 2nd 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 115 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 117 for electrically connecting the connection pads 115 and the mounting pads 116 provided on the lower surface and the external terminals 112 provided on the lower surface of the second frame 110c is provided on the surface of the substrate 110a. Is provided.

  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 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 first frame 110b and the second frame 110c are made of a ceramic material such as alumina ceramics or glass-ceramics, and are 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. Also, two of the four external terminals 112 are electrically connected to the temperature sensing element 150. Further, the first external terminal 112a and the third external terminal 112c that are electrically connected to the crystal element 120 are provided so as to be located diagonally on the lower surface of the second frame 110c. The second external terminal 112b 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 third external terminal 112c 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 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. 4 and 5, the electrode pad 111 is connected to the external terminal 112 provided on the lower surface of the second frame 110c via the wiring pattern 113 and the via conductor 114 provided on the upper surface of the substrate 110a. And are electrically connected.

  As shown in FIG. 4, the electrode pad 111 is composed of a first electrode pad 111a and a second electrode pad 111b. 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 as shown in FIG. 5B. 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 third external terminal 112c through the third via conductor 114c.

  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 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 second frame 110c. The second external terminal 112b is electrically connected to the sealing conductor pattern 118 through the second via conductor 114b.

  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 117, or the sealing conductor pattern 118. The via conductor 114 is provided by filling a conductor in a through hole provided in the substrate 110a. As shown in FIGS. 4 and 5, the via conductor 114 includes a first via conductor 114 a, a second via conductor 114 b, a third via conductor 114 c, and a fourth via conductor 114 d.

  The connection pad 115 has a rectangular shape and is used for mounting a temperature sensing element 150 described later. A pair of connection pads 115 are provided so as to be adjacent to the vicinity of the center of the lower surface of the substrate 110a. Further, as shown in FIG. 5, the connection pad 115 includes a first connection pad 115a and a second connection pad 115b. The conductive bonding material 170 is provided between the lower surface of the connection pad 115 and the connection terminal 151 of the temperature sensitive element 150.

  The mounting pad 116 has a trapezoidal shape in plan view, and is used for mounting the temperature sensitive element 150 and securing the amount of the conductive bonding material 170 described later. The mounting pad 116 is electrically connected to the connection pad 115, and is provided on the short side of the substrate 110 a with respect to the connection pad 115. In addition, the mounting pad 116 is provided so as to expand as it approaches the inner peripheral edge of the second frame portion 110b in plan view. That is, the mounting pad 116 has a trapezoidal shape in plan view, and the length of one side of the mounting pad 116 facing the center direction of the substrate 110a is the length of one side of the mounting pad 116 facing the outer peripheral direction of the substrate 110a. It is provided to be shorter than the length. By doing so, the temperature-sensitive element 150 is bonded to the connection pad 115 and the mounting pad 116 so that the conductive bonding material 170 spreads from the connection pad 115 toward the mounting pad 116 in a plan view. Further, the bonding strength of the temperature sensitive element 150 can be further improved. The mounting pad 116 includes a first mounting pad 116a and a second mounting pad 116b. In addition, the conductive bonding material 170 is formed with a fillet having an inclination such that the thickness gradually increases from the mounting pad 116 toward the connection terminal 151 of the temperature-sensitive element 150. By doing so, the thermosensitive element 150 can improve the bonding strength between the connection pad 115 and the mounting pad 116.

  The second mounting pad 116b 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 from the second mounting pad 116b to the second connection pad 115b 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.

  Here, taking the case where the long side dimension of the substrate 110a as viewed in plan is 1.2 to 2.5 mm and the short side dimension is 1.0 to 2.0 mm, the connection pad 115 is taken as an example. The size of the mounting pad 116 will be described. 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. It has become. The length of the side of the mounting pad 116 facing the center of the substrate 110a is 0.2 to 0.5 mm, and the length of the side facing the outer peripheral edge of the substrate 110a is 0.4 to 0.7 mm. ing. As described above, the length of one side of the mounting pad 116 facing the center of the substrate 110a is set shorter than the length of one side of the mounting pad 116 facing the outer peripheral edge of the substrate 110a. Therefore, since the conductive bonding material 170 is bonded so as to spread from the connection pad 115 toward the mounting pad 116 as shown in FIG. 3 in plan view, the bonding strength can be further improved. Become. Further, the length between the first connection pad 115a and the second connection pad 115b is 0.1 to 0.3 mm.

  The first connection pads 115a and the first mounting pads 116a and the second external terminals 112b are connected by a first connection pattern 117a provided on the lower surface of the substrate 110a. The second connection pads 115b and the second mounting pads 116b and the fourth external terminals 112d are connected by a second connection pattern 117b provided on the lower surface of the substrate 110a.

  The connection pattern 117 is provided on the lower surface of the substrate 110a, and is drawn out from the mounting pad 116 toward the nearby external terminal 112. Further, as shown in FIG. 4, the connection pattern 117 includes a first connection pattern 117a and a second connection pattern 117b. The length of the first connection pattern 117a and the length of the second connection pattern 117b are substantially equal. Here, the substantially equal length means that the difference between the length of the first connection pattern 117a provided on the lower surface of the substrate 110a and the length of the second connection pattern 117b provided on the lower surface of the substrate 110a is different by 0 to 200 μm. Shall be included. As for the length of the connection pattern 117, it is assumed that the length of a straight line passing through the center of each connection pattern 117 is measured. That is, when the wiring length of the first connection pattern 117a and the wiring length of the second connection pattern 117b 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 117b is provided so as to overlap the first electrode pad 111a in plan view. Further, by doing so, the heat transferred from the crystal element 120 is transferred from the second connection pattern 117b to the second mounting pad 116b and the second connection pad 115b via the substrate 110a immediately below the first electrode pad 111a. It will be transmitted. 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 118 plays a role of improving the wettability of the sealing member 131 when it is joined to the lid 130 via the sealing member 131. The sealing conductor pattern 118 is provided so as to surround the upper surface of the first frame 110b. As shown in FIGS. 3 and 4, the sealing conductor pattern 118 is electrically connected to the second external terminal 112b via the second via conductor 114b. The sealing conductor pattern 118 is formed to have a thickness of, for example, 10 to 25 μm by sequentially applying nickel plating and gold plating on the surface of the conductor pattern made of, for example, tungsten or molybdenum so as to surround the upper surface of the frame 110b in an annular shape Has been.

  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, predetermined portions of the conductor pattern, specifically, the electrode pad 111, the external terminal 112, the wiring pattern 113, the via conductor 114, the connection pad 115, the mounting pad 116, the connection pattern 117, and the sealing conductor pattern 118 are obtained. It is produced by applying nickel plating, gold plating, silver palladium or the like to the part. 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 extraction electrode 123a of the crystal element 120 is bonded to the second electrode pad 111b, and the second extraction electrode 123b is bonded to the first electrode pad 111a. As a result, the first external terminal 112 a and the third external terminal 112 c 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 through the second external terminal 112b and the fourth external terminal 112d, for example, a main IC such as an electronic device. 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 second external terminal 112b and the fourth external terminal 112d.

  As shown in FIG. 2, the temperature sensing element 150 is mounted on a connection pad 115 provided on the lower surface of the substrate 110a via a conductive bonding material 170 such as solder. The first connection terminal 151a of the temperature sensitive element 150 is connected to the first connection pad 115a, and the second connection terminal 151b is connected to the second connection pad 115b. The first connection pad 115a is connected to the second external terminal 112b via a first connection pattern 116a provided on the lower surface of the substrate 110a. The second external terminal 112b serves as a ground terminal by being connected to a mounting pad that is connected to a ground that is a reference potential on a mounting substrate of an electronic device or the like. Therefore, the first connection terminal 151a of the temperature sensitive element 150 is connected to the ground that is the reference potential.

  Further, the temperature sensing element 150 is positioned in the plane of the excitation electrode 122 provided on the crystal element 120 in plan view, so that the temperature sensing element 150 is shielded by the metal film of the excitation electrode 122. Protects against noise from other semiconductor components and electronic components such as power amplifiers constituting electronic devices. 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 pad 115 by a dispenser, for example. The temperature sensitive element 150 is placed on the conductive bonding material 170. The conductive bonding material 170 is melt bonded by heating. Therefore, the temperature sensitive element 150 is bonded to the pair of connection pads 115.

  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
For example, it is composed of silver paste or lead-free solder. The conductive bonding material 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 body 130 is placed on the first frame body 110b of the package 110 in a predetermined atmosphere, and the sealing conductor pattern 118 of the first frame body 110b and the sealing member 131 of the lid body 130 are arranged. Is welded to the first frame 110b by applying a predetermined current so as to be welded. The lid 130 is electrically connected to the second external terminal 112b on the lower surface of the second frame 110c via the sealing conductor pattern 118 and the second via conductor 114b. The second external terminal 112b is electrically connected to the second connection pad 115b and the second mounting pad 116b through the conductive bonding material 170. Therefore, the lid 130 is electrically connected to the second external terminal 112b of the package 110.

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

  The crystal resonator according to the embodiment of the present invention is provided on the lower surface of the substrate 110a and the pair of connection pads 115 provided on the lower surface of the substrate 110a in the second frame 110b. A pair of mounting pads 116, and the mounting pads 116 are provided in a trapezoidal shape in plan view so as to expand toward the inner peripheral edge of the second frame portion 110 b in plan view. Yes. By doing so, the conductive bonding material 170 is provided so as to spread along the mounting pad 116 from the connection pad 115 in plan view, and the connection of the temperature sensitive element 150 from the connection pad 115 and the mounting pad 116. A slope is formed so that the thickness of the conductive bonding material 170 gradually increases toward the side surface of the terminal 151. Since the temperature sensitive element 150 is bonded to the connection pad 115 and the mounting pad 116 in this manner, the amount of the conductive bonding material 170 can be secured, and the bonding strength between the conductive bonding material 170 and the temperature sensitive element 150 can be increased. It becomes possible to improve.

  In the crystal resonator according to the embodiment of the present invention, the crystal element 120 and the temperature-sensitive element 150 are mounted on the substrate 110a, and the crystal resonator 120 is in a plane of the excitation electrode 122 provided on the crystal element 120 in plan view. By positioning the temperature sensitive element 150 on the surface, the temperature sensitive element 150 is prevented from noise from other semiconductor components such as a power amplifier constituting the electronic device and electronic components by the shielding effect by the metal film of the excitation electrode 122. Protect. 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.

  Further, the crystal resonator according to the embodiment of the present invention is provided such that the electrode pad 111 is adjacent along one side of the inner peripheral edge of the first frame 110b, and one of the mounting pads 116 is viewed in plan view. The electrode pad 111 is provided between the pair of electrode pads 111. By doing so, the heat transferred from the crystal element 120 is transferred from the second mounting pad 116b to the second bonding pad 115b via the substrate 110a directly 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 117b 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 117b to the second mounting pad 116b and the second connection pad 115b via the substrate 110a immediately below the first electrode pad 111. become. 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.

(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 FIGS. 6 and 7, the crystal resonator in the first modification of the present embodiment includes a wiring pattern 213 for electrically connecting the electrode pad 211 and the external terminal 212. One of the wiring patterns 213 is different from the present embodiment in that one of the wiring patterns 213 is provided on the same plane as the connection pad 215 and is provided at a position overlapping the second frame 210c.

  As shown in FIG. 6, the electrode pad 211 is composed of a first electrode pad 211a and a second electrode pad 211b. Further, as shown in FIG. 7B, the external terminal 212 includes a first external terminal 212a, a second external terminal 212b, a third external terminal 212c, and a fourth external terminal 212d. The via conductor 214 includes a first via conductor 214a, a second via conductor 214b, a third via conductor 214c, a fourth via conductor 214d, and a fifth via conductor 214e. The wiring pattern 213 includes a first wiring pattern 213a, a second wiring pattern 213b, and a third wiring pattern 213c. The first electrode pad 211a is electrically connected to one end of the first wiring pattern 213a provided on the substrate 210a. The other end of the first wiring pattern 213a is electrically connected to one end of the third wiring pattern 213c via the first via conductor 214a. The other end of the third wiring pattern 213c is electrically connected to the first external terminal 212a via the fifth via conductor 214e. Therefore, the first electrode pad 211a is electrically connected to the first external terminal 212a. The second electrode pad 211b is electrically connected to one end of the second wiring pattern 213b provided on the substrate 210a. The other end of the second wiring pattern 213b is electrically connected to the third external terminal 212c through the third via conductor 214c.

  Further, as shown in FIGS. 6 and 7, the wiring pattern 213 includes a first wiring pattern 213a, a second wiring pattern 213b, and a third wiring pattern 213c. The first wiring pattern 213a and the second wiring pattern 213b are provided on the upper surface of the substrate 210a, and are drawn from the electrode pad 211 toward the via conductor 214 of the nearby substrate 210a. The third wiring pattern 213c is provided on the lower surface of the substrate 210a and is provided so as to be close to the connection pad 215 of the substrate 210a. That is, the distance between the third wiring pattern 213c and the connection pad 215b is 50 to 100 μm. By doing so, heat transferred from the crystal element 120 is transferred from the electrode pad 211 to the third wiring pattern 213c via the first wiring pattern 213a and the first via conductor 214a. Next, the heat transmitted from the crystal element 120 is transmitted from the third wiring pattern 213c to the connection pad 215 via the lower surface of the substrate 210a. Therefore, since the crystal resonator can shorten the heat conduction path, the temperature of the crystal element 120 and the temperature of the temperature sensitive element 150 are approximated, and the voltage output from the temperature sensitive element 150 is converted. Thus, the difference between the obtained temperature and the actual temperature around the quartz crystal element 120 can be reduced.

  The third wiring pattern 213c is provided at a position overlapping the second frame 210c. In this way, when the crystal resonator according to the first modification of the present embodiment is mounted on a mounting board such as an electronic device, the wiring conductor provided on the mounting board and the third wiring pattern 213c. The stray capacitance generated between the two can be reduced. Therefore, fluctuation of the oscillation frequency of the crystal element 120 can be reduced while suppressing the stray capacitance from being added to the crystal element 120.

  The crystal resonator in the first modification of the present embodiment includes a wiring pattern 213 for electrically connecting the electrode pad 211 and the external terminal 212, and the third wiring pattern 213 c is flush with the connection pad 215. It is provided in the position which overlaps with the 2nd frame 210c. By doing so, the heat transmitted from the crystal element 120 is transmitted from the first electrode pad 211a to the third wiring pattern 213c via the first wiring pattern 213a and the first via conductor 214a. Next, the heat transmitted from the crystal element 120 is transmitted from the third wiring pattern 213c to the connection pad 215 and the mounting pad 216 via the lower surface of the substrate 210a. Therefore, since the crystal resonator can shorten the heat conduction path, the temperature of the crystal element 120 and the temperature of the temperature sensitive element 150 are approximated, and the voltage output from the temperature sensitive element 150 is converted. Thus, the difference between the obtained temperature and the actual temperature around the quartz crystal element 120 can be reduced.

  Further, in the crystal resonator according to the first modification of the present embodiment, the third wiring pattern 213c is provided at a position where it overlaps with the second frame 210c. By doing so, when the crystal resonator of the present embodiment is mounted on a mounting board such as an electronic device, it is generated between the wiring conductor provided on the mounting board and the third wiring pattern 213c. The stray capacitance to be reduced can be reduced. Therefore, fluctuation of the oscillation frequency of the crystal element 120 can be reduced while suppressing the stray capacitance from being added to the crystal element 120.

(Second modification)
Hereinafter, the crystal resonator according to the second modification of the present embodiment will be described. Note that, in the crystal resonator according to the second 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 FIGS. 8 to 10, the crystal resonator according to the second modification of the present embodiment is formed on the substrate 310 a so that the long side of the temperature sensing element 150 is parallel to the short side of the substrate 310 a. It differs from the first modification of this embodiment in that it is mounted on the connection pad 315 and the mounting pad 316.

  The connection pad 315 has a rectangular shape and is provided near the center of the lower surface of the substrate 310a. As shown in FIG. 10, the connection pads 315 are provided adjacent to each other so that the long sides of the connection pads 315 and the short sides of the substrate 310a are parallel to each other. The connection pad 315 includes a first connection pad 315a and a second connection pad 315b.

  The mounting pad 316 has a rectangular shape and is electrically connected to the connection pad 315. Further, the mounting pad 316 is provided so as to be located on the long side of the substrate 310 a with respect to the connection pad 315. The conductive bonding material 170 is formed with a fillet having an inclination such that the thickness gradually increases from the mounting pad 316 toward the connection terminal 151 of the temperature-sensitive element 150. By doing so, the temperature sensitive element 150 can improve the bonding strength between the connection pad 315 and the mounting pad 316.

  Further, the second mounting pad 316b is provided at a position overlapping the first wiring pattern 313a as shown in FIGS. 9 and 10 in plan view. By doing so, heat transferred from the crystal element 120 is transferred from the first electrode pad 311a to the first wiring pattern 313a, and from the second mounting pad 316b via the substrate 310a immediately below the first wiring pattern 313a. It is transmitted to the second connection pad 315b. 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.

  As shown in FIG. 10, the connection pattern 317 is provided on the lower surface of the substrate 310 a and is drawn out from the mounting pad 316 toward the neighboring via conductor 314. The second connection pattern 317b is provided so as to overlap the first wiring pattern 313a. By doing so, heat transmitted from the crystal element 120 is transmitted from the first electrode pad 311a to the first wiring pattern 313a, and from the second connection pattern 317b via the substrate 310a directly below the first wiring pattern 313a. It is transmitted to the second mounting pad 316b and the second connection pad 315b. 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 310a 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. The size of the mounting pad 316 will be described. The length of the side of the connection pad 315 parallel to the long side of the substrate 310a is 0.2 to 0.5 mm, and the length of the side parallel to the short side of the substrate 310a is 0.25 to 0.55 mm. It has become. The length of the side of the mounting pad 316 facing the center direction of the substrate 310a is 0.2 to 0.5 mm, and the length of the side facing the outer peripheral edge direction of the substrate 310a is 0.4 to 0.7 mm. ing. As described above, the length of one side of the mounting pad 316 that faces the center of the substrate 310a is set shorter than the length of one side of the mounting pad 316 that faces the outer peripheral edge of the substrate 310a. Therefore, since the conductive bonding material 170 is bonded so as to spread from the connection pad 315 toward the mounting pad 316 as shown in FIG. 8 in plan view, the bonding strength can be further improved. Become. Further, the length between the first connection pad 315a and the second connection pad 315b is 0.1 to 0.3 mm.

  The temperature sensing element 150 is mounted on the lower surface of the substrate 310a so that the long side of the temperature sensing element 150 and the short side of the substrate 310a are parallel to each other. By doing in this way, the area of the external terminal 313 provided at the four corners of the lower surface of the second frame 310c can be made larger than the area of the external terminal 112 of the present embodiment. Bonding strength can be improved when mounted on a mounting substrate such as an electronic device.

  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, 310 ... package 110a, 210a, 310a ... substrate 110b, 210b, 310b ... first frame 110c, 210c, 310c ... second frame 111, 211, 311 ... Electrode pads 112, 212, 312 ... External terminals 113, 213, 313 ... Wiring patterns 114, 214, 314 ... Via conductors 115, 215, 315 ... Connection pads 116, 216, 316 ... Mounting pads 117, 217, 317 ... connection patterns 118, 218, 318 ... sealing conductor patterns 120 ... crystal element 121 ... crystal base plate 122 ... excitation electrode 123 ... lead-out Electrode 130 ... Lid 131 ... Sealing member 140 ... Conductive adhesive 150 ... Temperature sensitive element 151 ... Contact Terminal K1 · · · first recess K2 · · · second recess

Claims (4)

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 the upper surface of the substrate in the first frame;
A pair of connection pads provided on the lower surface of the substrate in the second frame;
A pair of mounting pads electrically connected to the connection pads and provided on the lower surface of the substrate;
A crystal element mounted on the electrode pad;
A temperature sensitive element mounted with a conductive bonding material on the connection pad and the mounting pad;
A lid joined to the upper surface of the first frame,
The crystal oscillator according to claim 1, wherein the mounting pad is provided so as to expand as it approaches the inner peripheral edge of the second frame portion in plan view. The crystal resonator according to claim 1,
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. A crystal resonator. The crystal resonator according to claim 1 or 2,
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 mounting pads is provided so as to be positioned between the pair of electrode pads in plan view. The crystal resonator according to claim 1, wherein:
A wiring pattern for electrically connecting the electrode pad and the external terminal;
One of the wiring patterns is provided on the same plane as the connection pad, and is provided at a position overlapping the second frame.

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