JP6542583B2 - Crystal oscillator - Google Patents

Description

  The present invention relates to a quartz oscillator used in an electronic device or the like.

  The quartz oscillator generates a specific frequency using the piezoelectric effect of the quartz crystal element. For example, a package having a substrate, a first frame provided on the upper surface of the substrate to provide the first recess, and a second frame provided on the lower surface of the substrate to provide the second recess And a quartz crystal element provided with a quartz crystal element mounted on an electrode pad provided on the upper surface of the substrate and a temperature sensing element mounted on a connection pad provided on the lower surface of the substrate (for example, (See Patent Document 1 below).

JP 2012-80250 A

  In the above-described crystal unit, the temperature sensitive element is mounted in the second recess using a conductive bonding material such as solder. As the miniaturization advances and the area of the connection pad formed in the second recess also becomes smaller, the amount of the conductive bonding material provided on the connection pad is reduced, and the conductive bonding material and the temperature sensitive element There was a risk that the bonding strength would decrease. In addition, since such a quartz oscillator also reduces the shape of the second recess in a plan view, the mounting nozzle is the inner wall of the second recess when the temperature-sensitive element is mounted in the second recess. There is a risk that the package may be chipped.

  The present invention has been made in view of the above problems, and it is an object of the present invention to provide a quartz oscillator capable of improving the bonding strength between a conductive bonding material and a temperature sensitive element and suppressing the occurrence of chipping in a package. It will be an issue.

A crystal unit according to one aspect of the present invention includes a rectangular substrate, a first frame provided on the upper surface of the substrate, a second frame provided on the lower surface of the substrate, the substrate, and the first frame In the first recess formed on the upper surface of the substrate, and in the second recess formed by the substrate and the second frame on the lower surface of the substrate An external terminal provided at four corners of the lower surface of the second frame, a crystal element mounted on the electrode pad, a temperature-sensitive element mounted on the connection pad via the conductive bonding material, and the first frame And the shape of the opening of the second recess is polygonal in plan view, and the corner of the opening of the second recess is adjacent in plan view to provided so as to be positioned between the external terminals, the four external terminals located near the hypotenuse connecting the two corners of the opening of the second recess , Chamfering is formed at a position facing the hypotenuse.

A crystal unit according to one aspect of the present invention includes a rectangular substrate, a first frame provided on the upper surface of the substrate, a second frame provided on the lower surface of the substrate, the substrate, and the first frame In the first recess formed on the upper surface of the substrate, and in the second recess formed by the substrate and the second frame on the lower surface of the substrate An external terminal provided at four corners of the lower surface of the second frame, a crystal element mounted on the electrode pad, a temperature-sensitive element mounted on the connection pad via the conductive bonding material, and the first frame And the shape of the opening of the second recess is polygonal in plan view, and the corner of the opening of the second recess is adjacent in plan view Near the oblique side connecting the two corners of the opening of the second recess.
In the four external terminals located here, corner chamfers are formed at positions facing the oblique side. By doing so, the shape of the second recess can be enlarged in the crystal unit, so the area of the connection pad can be increased as compared to the case where the conventional crystal unit is miniaturized. Therefore, the amount of the conductive bonding material provided on the connection pad can be secured, and the bonding strength between the conductive bonding material and the temperature sensitive element can be improved. In addition, since such a quartz oscillator can increase the shape of the second recess in a plan view, the mounting nozzle is the inner wall of the second recess when mounting the temperature sensing element in the second recess. It is possible to reduce the occurrence of chipping in the package because it is prevented from coming into contact with the package.

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

  As shown in FIGS. 1 to 5, the crystal unit according to this 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. And 150. The package 110 is formed with a first recess K1 surrounded by the upper surface of the substrate 110a and the inner surface of the first frame 110b. Further, a second concave portion K2 surrounded by the lower surface of the substrate 110a and the inner side surface of the second frame 110c is formed. Such a crystal unit is used to output a reference signal used in an electronic device or the like.

  The substrate 110 a has a rectangular shape, and functions as a mounting member for mounting the crystal element 120 mounted on the upper surface and the temperature sensing element 150 mounted on the lower surface. An electrode pad 111 for mounting the quartz crystal element 120 is provided on the upper surface of the substrate 110a, and a connection pad 117 for mounting the temperature sensitive element 150 is provided on the lower surface. In addition, along one side of the substrate 110a, a first electrode pad 111a and a second electrode pad 111b for bonding the crystal element 120 are provided.

  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 be formed by using a single insulating layer or by stacking a plurality of insulating layers. Wiring patterns 113 and via conductors 114 for electrically connecting the electrode pads 111 provided on the upper surface and the external terminals 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, on the surface of the substrate 110a, a connection pattern 118 for electrically connecting the connection pad 117 provided on the lower surface and the external terminal 112 provided on the lower surface of the second frame 110b 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 in the upper surface of the substrate 110a. The first frame 110 b is made of, for example, a ceramic material such as alumina ceramic or glass-ceramics, and is integrally formed with the substrate 110 a. The opening of the first recess K1 has a rectangular shape when viewed in plan.

  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 in the lower surface of the substrate 110a. The second frame 110 c is made of, for example, a ceramic material such as alumina ceramic or glass-ceramics, and is integrally formed with the substrate 110 a. External terminals 112 are provided at the four corners of the lower surface of the second frame 110 c. In addition, two of the four external terminals 112 are electrically connected to the crystal element 120. Also, the remaining two of the four external terminals 112 are electrically connected to the temperature sensitive element 150. In addition, the first external terminal 112a and the second external terminal 112b electrically connected to the crystal element 120 are provided to be diagonally located on the lower surface of the second frame 110c. The third external terminal 112 c and the fourth external terminal 112 d electrically connected to the temperature sensing element 150 are provided with a first external terminal 112 a and a second external terminal 112 b connected to the crystal element 120. It is provided so as to be located at a diagonal of the second frame 110c different from the diagonal.

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

  By doing this, the space between the adjacent external terminals 112 can be used, so the area of the opening of the second recess K2 corresponds to that of the second recess K2 when the conventional quartz oscillator is miniaturized. Since the area of the opening can be made larger, the area of the connection pad 117 can also be made larger. Therefore, the amount of the conductive bonding material 170 provided on the connection pad 117 can be secured, and the bonding strength between the conductive bonding material 170 and the temperature sensitive element 150 can be improved. In addition, when mounting the temperature sensing element 150 in the second recess K2, the mounting nozzle is prevented from coming into contact with the inner wall of the second recess K2, so that chipping of the package 110 can be reduced. .

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

  The corner C of the opening of the second recess K2 is formed in an arc shape. By doing this, when the piezoelectric device of the present embodiment is mounted on the mounting substrate of the electronic device, even if stress is applied to the package 110, the corner portion C has an arc shape, so the corner portion The stress applied to the package 110 can be dispersed, and cracking of the package 110 can be reduced. Moreover, the curvature radius of the corner part C which became circular arc shape is 0.10-0.20 mm.

  Here, the dimension of one side when the package 110 is viewed in plan is 1.0 to 3.0 mm, and the dimension of the package 110 in the vertical direction is 0.2 to 1.5 mm as an example. The sizes of the first recess K1 and the second recess K2 will be described. The length of the long side of the first recess K1 is 0.7 to 2.0. The length of the short side is 0.5 to 1.5 mm. Moreover, the length of the up-down direction of 1st recessed part K1 is 0.1-0.5 mm. The length of the side of the second recess K2 parallel to the short side of the substrate 110a is 0.3 to 0.8 mm, and the length of the side of the second recess K2 parallel to the long side of the substrate 110a is It is 0.6 to 2.0 mm. Moreover, the length of the up-down direction of 2nd recessed part K2 is 0.1-0.5 mm.

  The electrode pad 111 is for mounting the crystal element 120. The electrode pads 111 are provided in a pair on the upper surface of the substrate 110a, and are provided adjacent to each other along one side of the substrate 110a. The electrode pad 111 is electrically connected to the external terminal 112 provided on the lower surface of the substrate 110 a through the wiring pattern 113 provided on the upper surface of the substrate 110 a and the via conductor 114 as shown in FIGS. 3 and 5. It is connected to the.

  The electrode pad 111 is comprised by the 1st electrode pad 111a and the 2nd electrode pad 111b, as shown to FIG. 3 and FIG. Further, as shown in FIG. 4 and FIG. 6B, the external terminal 112 is constituted by a first external terminal 112a, a second external terminal 112b, a third external terminal 112c and a fourth external terminal 112d. The via conductor 114 is constituted by the first via conductor 114a and the second via conductor 114b, the third via conductor 114c and the fourth via conductor 114d. Further, the wiring pattern 113 is configured of a first wiring pattern 113a and a second wiring pattern 113b. The first electrode pad 111a is electrically connected to one end of a 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 via the first via conductor 114a. Thus, 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 a second wiring pattern 113b provided on the substrate 110a. The other end of the second wiring pattern 113b is electrically connected to the second external terminal 112b via the second via conductor 114b.

  The arithmetic mean surface roughness of the electrode pad 111 is 0.02 to 0.10 μm, and the arithmetic mean surface roughness of the surface of the substrate 110 a is 0.5 to 1.5 μm. Therefore, the conductive adhesive 140 spreads in the direction of the wiring pattern 113 where the convex portion 115 is not provided on the electrode pad 111, but from the electrode pad 111 to the substrate It becomes difficult to spread toward above 110a.

  The external terminal 112 is used to electrically bond with a mounting substrate (not shown) of an electronic device or the like. The external terminals 112 are provided at the four corners of the lower surface of the second frame 110 c. Two of the external terminals 112 are electrically connected to a pair of electrode pads 111 provided on the top surface of the substrate 110a. The other two of the external terminals 112 are electrically connected to a pair of connection pads 117 provided on the lower surface of the substrate 110a. Further, external terminals 112 electrically connected to the electrode pads 111 are provided so as to be located diagonally on the lower surface of the substrate 110a. The third external terminal 112c is electrically connected to the sealing conductor pattern 119 via the third via conductor 114c. The first external terminal 112a has a shape that is chamfered at a position facing the oblique side connecting the corner C1 and the corner C8, and the second external terminal 112b has the corner C4 and the corner C5. It has a shape in which chamfering is performed at the position opposite to the oblique side connecting the two. The third external terminal 112c has a shape in which cornering is performed at a position opposite to the oblique side connecting the corner C6 and the corner C7, and the fourth external terminal 112d has a corner C2 and a corner It has a shape in which chamfering is performed at a position facing the oblique side connecting the portion C3. In this way, when the crystal unit of the present embodiment is mounted on a mounting substrate of an electronic device or the like, the solder provided on the external terminal 112 is crushed and enters the second recess K2. It can be reduced.

  The wiring pattern 113 is provided on the upper surface of the substrate 110 a and is drawn from the electrode pad 111 toward the nearby via conductor 114. Further, as shown in FIG. 4, the wiring pattern 113 is constituted by a first wiring pattern 113a and a second wiring pattern 113b.

  The via conductor 114 is provided inside the substrate 110 a, and both ends thereof are electrically connected to the wiring pattern 113, the connection pattern 118, or the sealing conductor pattern 119. The via conductor 114 is provided by filling the inside of the through hole provided in the substrate 110 a with the conductor. Also, as shown in FIG. 3 and FIG. 5, the via conductor 114 is configured by the first via conductor 114 a, the second via conductor 114 b, the third via conductor 114 c, and the fourth via conductor 114 d.

  The convex portion 115 is intended to suppress inclination of the short side of the quartz crystal element 120 in the vertical direction and to prevent the long side end of the quartz crystal element 120 from coming into contact with the substrate 110 a or the lid 130. Further, the convex portion 115 is for suppressing the free end of the crystal element 120 from coming into contact with the substrate 110 a. The pair of convex portions 115 is configured of a first convex portion 115 a and a second convex portion 115 b. The first convex portion 115a is provided on the upper surface of the first electrode pad 111a, and the second convex portion 115b is provided on the upper surface of the second electrode pad 111b. Similarly to the electrode pad 111, the convex portion 115 is provided by performing gold plating or nickel plating on the upper surface of a sintered body of metal powder such as tungsten, molybdenum, copper, silver or silver palladium.

  Further, as shown in FIG. 3 and FIG. 5, one side of the pair of convex portions 115 facing the center side of the substrate 110 a is provided on the same straight line. In this way, when the lead-out electrode 123 of the crystal element 120 is mounted on the electrode pad 111 while being in contact with the pair of convex portions 115, the crystal element 120 can be mounted in a stable state without tilting.

  In addition, the convex portion 115 is provided at a position facing the lead electrode 123 on the outer peripheral edge of the crystal element 120. By doing this, when the crystal element 120 is mounted on the electrode pad 111 via the conductive adhesive 140, even if the crystal element 120 is inclined, the lead-out electrode 123 contacts the convex portion 115. Thus, the crystal element 120 can be mounted in a stable state without being inclined in the lower direction than the convex portion 115. Further, the convex portion 115 is provided at a position overlapping the lead-out electrode 123 on the outer peripheral edge on the fixed end side of the quartz crystal substrate 121 in plan view. By doing so, the contact of the fixed end of the quartz crystal element 120 with the upper surface of the substrate 110a can be reduced.

  The protrusion 116 has a rectangular shape in plan view and is provided at a position opposite to the free end of the quartz crystal element 120, and prevents the free end of the quartz crystal element 120 from contacting the substrate 110a. It is. The protrusion 116 is provided on the substrate 110 a in the first recess K 1 such that the long side of the protrusion 116 and the long side of the substrate 110 a are substantially parallel. In this way, it is possible to suppress chipping or the like due to the free end side of the crystal element 120 coming into contact with the substrate 110 a when an impact such as a drop is applied to the crystal unit.

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

  Further, the second connection pad 117 b is provided so as to be located between the pair of electrode pads 111 in plan view. Also, with this configuration, the heat transmitted from the quartz crystal element 120 is transmitted to the second connection pad 117 b through the substrate 110 a immediately below the electrode pad 111. Therefore, since such a quartz oscillator can further shorten the heat conduction path, the temperature of the quartz crystal element 120 and the temperature of the temperature sensing element 150 approximate each other, and the temperature is outputted from the temperature sensing element 150. It is possible to further reduce the difference between the temperature obtained by converting the voltage and the actual temperature around the crystal element 120.

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

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

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

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

  The sealing conductor pattern 119 plays the role of improving the wettability of the bonding member 131 when bonding the lid 130 and the bonding member 131 via the bonding member 131. The sealing conductor pattern 119 is provided so as to surround the upper surface of the first frame 110 b. As shown in FIGS. 5 and 6, the sealing conductor pattern 119 is electrically connected to the third external terminal 112c via the third via conductor 114c. The sealing conductor pattern 119 has a thickness of, for example, 10 to 25 μm by applying nickel plating and gold plating sequentially on the surface of a conductor pattern made of, for example, tungsten or molybdenum in a form of annularly surrounding the upper surface of the first frame 110b. Is formed.

  Here, a method for manufacturing the substrate 110a will be described. When the substrate 110a is made of alumina ceramic, first, a plurality of ceramic green sheets obtained by adding and mixing an appropriate organic solvent and the like to a predetermined ceramic material powder are prepared. Further, a predetermined conductive paste is applied by screen printing or the like known in the prior art in the surface of the ceramic green sheet or in the through holes which are punched in advance by punching or the like. Furthermore, these green sheets are stacked and press-formed, and 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 external terminal 112, the wiring pattern 113, the via conductor 114, the connection pad 117, the connection pattern 118, and the sealing conductor pattern 119. Moreover, it is produced by giving gold plating, silver palladium, etc. The conductor paste is made of, for example, a sintered body of metal powder such as tungsten, molybdenum, copper, silver or silver palladium.

  The quartz crystal element 120 is bonded onto the electrode pad 111 via the conductive adhesive 140 as shown in FIGS. 1 and 2. The quartz crystal element 120 plays a role of oscillating a reference signal of an electronic device or the like by the stable mechanical vibration and the piezoelectric effect.

  Further, as shown in FIG. 1 and FIG. 2, the quartz crystal element 120 has a structure in which the excitation electrode 122 and the lead-out electrode 123 are adhered to the upper surface and the lower surface of the quartz substrate 121 respectively. . The excitation electrode 122 is formed by depositing and forming a metal on each of the upper surface and the lower surface of the quartz crystal substrate 121 in a predetermined pattern. The excitation electrode 122 includes a first excitation electrode 122 a on the upper surface and a second excitation electrode 122 b on the lower surface. The lead-out electrodes 123 extend from the excitation electrode 122 toward one side of the quartz substrate 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 lead-out electrode 123 a is drawn out from the first excitation electrode 122 a and provided so as to extend toward one side of the quartz crystal base plate 121. The second lead-out electrode 123 b is drawn out from the second excitation electrode 122 b and provided so as to extend toward one side of the quartz 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 substrate 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 quartz crystal element 120 is fixed on the substrate 110 a by a cantilevered support structure with free ends.

  Here, the operation of the crystal element 120 will be described. In the quartz crystal element 120, when an alternating voltage from the outside is applied from the extraction electrode 123 to the quartz crystal base plate 121 via the excitation electrode 122, the quartz crystal base 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 quartz crystal element 120 is cut at a predetermined cut angle from the artificial crystalline lens to reduce the thickness of the outer periphery of the quartz crystal base plate 121, and the central portion of the quartz crystal base plate 121 becomes thicker than the outer periphery of the quartz crystal base plate 121. Perform bevel processing to be provided. Then, the quartz crystal element 120 is manufactured by forming the excitation electrode 122 and the lead-out electrode 123 by depositing a metal film on both principal surfaces of the quartz crystal base plate 121 by photolithography, vapor deposition technology or sputtering technology. Be done.

  A method of bonding the crystal element 120 to the substrate 110 a will be described. First, the conductive adhesive 140 is applied onto the first electrode pad 111a and the second electrode pad 111b by, for example, a dispenser. The quartz crystal element 120 is carried on the conductive adhesive 140 and placed on the conductive adhesive 140. The conductive adhesive 140 is cured and shrunk by heat curing. The crystal element 120 is bonded to the electrode pad 111. That is, the first lead-out electrode 123a of the quartz crystal element 120 is joined to the first electrode pad 111a, and the second lead-out electrode 123b is joined to the second electrode pad 111b. As a result, the first external terminal 112 a and the second external terminal 112 b are electrically connected to the crystal element 120.

  The conductive adhesive 140 contains a conductive powder as a conductive filler in a binder such as silicone resin, and as the conductive powder, aluminum, molybdenum, tungsten, platinum, palladium, silver, titanium, Those containing either nickel or nickel-iron or combinations thereof are used. Moreover, as a binder, a silicone resin, an epoxy resin, a polyimide resin, or bis maleimide resin is used, for example.

  As the temperature sensing element 150, a thermistor, a platinum temperature measuring resistor, 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 connection terminals 151 are provided at both ends. The temperature sensing element 150 shows a marked change in the electrical resistance due to a temperature change, and the voltage changes due to the change in the resistance value. Therefore, the temperature sensor 150 outputs an output according to the relation between the resistance value and the voltage Temperature information can be obtained from the output voltage. The temperature sensing element 150 outputs the voltage between the connection terminals 151, which will be described later, to the outside of the crystal unit via the third external terminal 112c and the fourth external terminal 112d, for example, as a main IC of an electronic device or the like. Temperature information can be obtained by converting the voltage output at (not shown) into temperature. Such a temperature sensing element 150 is disposed near the quartz oscillator, and according to the temperature information of the quartz oscillator obtained by this, the voltage for driving the quartz oscillator is controlled by the main IC, so-called temperature compensation You can

When a platinum temperature measuring resistor is used, the temperature sensing element 150 is formed by depositing platinum on the center of a rectangular parallelepiped ceramic plate, and a platinum electrode is provided. Further, connection terminals 151 are provided at both ends of the ceramic plate. The platinum electrode and the connection terminal are connected by a lead-out electrode provided on the upper surface of the ceramic plate. An insulating resin is provided to cover the top surface of the platinum electrode.

  When a diode is used, the temperature sensing element 150 has a structure in which the semiconductor element is mounted on the upper surface of the semiconductor element substrate and the upper surface of the semiconductor element and the semiconductor element substrate is covered with the insulating resin. . Connection terminals 151 serving as an anode terminal and a cathode terminal are provided on the lower surface to the side surface of the semiconductor element substrate. The temperature sensing element 150 has forward characteristics 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 largely change with temperature. Voltage information can be obtained by supplying a constant current to the temperature sensing element and measuring the forward voltage. By converting the voltage information, 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 112c and the fourth external terminal 112d.

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

  Further, since the temperature sensing element 150 is positioned in the plane of the excitation electrode 122 provided on the quartz crystal element 120 in a plan view, the temperature sensing element 150 is shielded by the shielding effect of the metal film of the excitation electrode 122. Protects from noise from other semiconductor components and electronic components such as power amplifiers that constitute the device. Therefore, the shielding effect of the excitation electrode 122 can reduce the noise from being superimposed on the temperature sensing element 150, and the accurate voltage of the temperature sensing element 150 can be output. 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 actual temperature information around the crystal element 120 It is possible to further reduce the difference between

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

  When the temperature sensing 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 terminals 151 a are provided on the right side surface and the upper and lower surfaces of the temperature sensing element 150. The second connection terminals 151 b are provided on the left side surface and the upper and lower surfaces of the temperature sensing element 150. The length of the long side of the temperature sensing 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 sensing 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 170 contains an added solvent for adjusting the viscosity to be easy to apply. The component ratio of lead-free solder is 95 to 97.5% of tin, 2 to 4% of silver, and 0.5 to 1.0% of copper.

  The lid 130 is made of, for example, an alloy containing at least one of iron, nickel and cobalt. Such a lid 130 is for airtightly sealing the first recess K1 in a vacuum state or the first recess K1 filled with nitrogen gas or the like. Specifically, the lid 130 is placed on the first frame 110 b of the package 110 in a predetermined atmosphere, and the sealing conductor pattern 119 of the first frame 110 b and the bonding member 131 of the lid 130 are It joins to the 1st frame 110b by applying predetermined electric current so that it may be welded, and performing seam welding. In addition, the lid 130 is electrically connected to the third external terminal 112 c on the lower surface of the substrate 110 a via the sealing conductor pattern 119 and the third via conductor 114 c. The third external terminal 112 c is electrically connected to the first connection pad 117 a via the first connection pattern 118. Accordingly, the lid 130 is electrically connected to the connection terminal 151 b of the temperature sensing element 150 and the third external terminal 112 c of the substrate 110 a.

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

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

  The bonding member 131 is, for example, in the case of gold-tin, the thickness of the layer of the bonding member 131 is 10 to 40 μm, for example, 70 to 80% of gold and 20 to 30% of tin. You may use In the case of silver solder, for example, the thickness of the layer of the bonding member 131 is 10 to 40 μm. For example, the component ratio is 70 to 80% of silver and 20 to 30% of copper. You may use the one of

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

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

  The crystal unit according to the embodiment of the present invention has the corner portion C of the opening of the second concave portion K2 formed into an arc shape in plan view, so that the crystal unit according to the present embodiment can be used as a mounting substrate for electronic devices Even when stress is applied to the package 110 when mounted on the upper side, the stress applied to the corner portion C is dispersed and the package 110 is cracked because the corner portion C has an arc shape. It can be reduced.

  Further, the crystal unit in the embodiment of the present invention senses within the plane of the excitation electrode 122 provided on the crystal element 120 in plan view in a state where the crystal element 120 and the temperature sensing element 150 are mounted on the substrate 110a. By positioning the thermal element 150, the temperature sensitive element 150 is protected from noise from other semiconductor parts and electronic parts such as a power amplifier constituting the electronic apparatus by the shield effect by the metal film of the excitation electrode 122. . Therefore, the shielding effect of the excitation electrode 122 can reduce the noise from being superimposed on the temperature sensing element 150, and the accurate voltage of the temperature sensing element 150 can be output. 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 actual temperature information around the crystal element 120 It is possible to further reduce the difference between

  Further, the crystal unit in 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 110 b, and one of the connection pads 117 is viewed in plan It is provided so as to be located between the pair of electrode pads 111. By doing this, the heat transmitted from the quartz crystal element 120 is transmitted to the second connection pad 117 b through the substrate 110 a immediately below the electrode pad 111. Therefore, since such a quartz oscillator can further shorten the heat conduction path, the temperature of the quartz crystal element 120 and the temperature of the temperature sensing element 150 approximate each other, and the temperature is outputted from the temperature sensing element 150. It is possible to further reduce the difference between the temperature obtained by converting the voltage and the actual temperature around the crystal element 120.

  Further, in the crystal unit in the embodiment of the present invention, the second connection pattern 118 b is provided so as to overlap with the first electrode pad 111 a in plan view. By doing this, the heat transmitted from the quartz crystal element 120 is transmitted from the second connection pattern 118 b to the second connection pad 115 b through the substrate 110 a immediately below the first electrode pad 111 a. In such a crystal unit, the temperature of the crystal element 120 and the temperature of the temperature sensing element 150 are further approximated by further shortening the heat conduction path and further increasing the number of the heat conduction paths, and thus the temperature sensing It is possible to further reduce the difference between the temperature obtained by converting the voltage output from the element 150 and the actual temperature around the crystal element 120.

  The crystal unit in the present embodiment includes a rectangular substrate 110a, a first frame 110b provided along the outer periphery of the upper surface of the substrate 110a, an electrode pad 111 provided on the upper surface of the substrate 110a, and an electrode A wiring pattern 113 electrically connected to the pad 111 and provided on the upper surface of the substrate 110a, a quartz crystal element 120 mounted on the electrode pad 111, and a lid 130 for hermetically sealing the quartz crystal element 120 The wiring pattern 113 is electrically connected to the electrode pad 111, and is provided at a position overlapping the first frame 110b in plan view. By doing this, the crystal unit can suppress generation of stray capacitance between the wiring pattern 113 and the crystal element 120. In addition, since such a crystal resonator does not have the floating capacitance applied to the crystal element 120, fluctuation of the oscillation frequency can be reduced. Further, in the crystal unit in the present embodiment, even if an external force is applied to the crystal unit and a bending moment is generated in the long side direction of the first frame 110b, the first frame 110b is provided in addition to the substrate 110a. As a result, the portion where the first frame 110b is provided is less likely to be deformed. Therefore, the wiring pattern 113 provided at a position overlapping with the first frame 110 b in plan view is unlikely to be disconnected, and it can be suppressed that the oscillation frequency of the crystal unit is not output.

  In the crystal unit in the present embodiment, a part of the wiring pattern 113 extends from the electrode pad 111 in the direction of the long side of the frame 110 b and is exposed. Thus, a part of the wiring pattern 113 extends from the electrode pad 111 in the long side direction of the first frame 110 b and is provided so as to be exposed in the first concave portion K 1. When the element 120 is mounted, the conductive adhesive 140 which has overflowed flows out on the wiring pattern 113 having good wettability with the conductive adhesive 140, and therefore flows out toward the center of the package 110. Therefore, the conductive adhesive 140 can be prevented from adhering to the excitation electrode 122.

  Further, in the crystal unit in the present embodiment, the electrode pad 111 is provided along one side of the substrate 110 a, and includes the convex portion 115 provided on the upper surface of the electrode pad 111. When the quartz crystal element 120 is mounted on the electrode pad 111 via the conductive adhesive 140, even if the quartz crystal element 120 is inclined, the lead-out electrode 123 will be in contact with the convex portion 115, and the convex electrode 115 The crystal element 120 can be mounted in a stable state without being inclined downward. Further, the convex portion 115 is provided at a position overlapping the lead-out electrode 123 on the outer peripheral edge on the fixed end side of the quartz crystal substrate 121 in plan view. By doing so, the contact of the fixed end of the quartz crystal element 120 with the upper surface of the substrate 110a can be reduced.

  In addition, the crystal unit in the present embodiment includes the protrusion 116 provided along the side facing the one side of the substrate 110 a. By doing this, when an impact such as a drop is applied to the quartz crystal unit, the free end side of the quartz crystal element 120 contacts the projection 116, thereby suppressing chipping due to direct contact with the substrate 110a. it can.

(First modification)
Hereinafter, the crystal unit in the first modification of the present embodiment will be described. In the crystal unit in the first modified example of the embodiment, the same parts as those of the above-described crystal unit are denoted by the same reference numerals, and the description will be appropriately omitted. The crystal unit in the first modified example of the present embodiment is, as shown in FIG. 7, the present embodiment in that the shape of the opening of the second recess K2 is hexagonal in plan view. It is different from

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

  Further, the crystal unit in the first modified example of the present embodiment is formed such that the shape of the opening of the second recess K2 is hexagonal in plan view. By doing so, the same effect as that of the embodiment can be obtained.

  The present invention is not limited to the present embodiment, and various changes, improvements, and the like can be made without departing from the scope of the present invention. In the above embodiment, the quartz crystal element has been described for the case where the quartz crystal element for AT is used, but a tuning fork type curved quartz crystal having a base and two flat vibrating arms extending in the same direction from the side surface of the base An element may be used.

  Moreover, the bevel processing method of the crystal element 120 is demonstrated. An abrasive having media of predetermined particle size and abrasive grains, and a quartz crystal substrate 121 formed to a predetermined size are prepared. The abrasive prepared on the cylindrical body and the quartz crystal raw plate 121 are put in, and the open end of the cylindrical body is closed with a cover. The crystal base plate 121 is rotated by rotating the cylindrical body containing the abrasive and the quartz crystal base plate 121 with the central axis of the cylindrical body as the rotation axis, and is beveled.

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

DESCRIPTION OF SYMBOLS 110, 210 ... Package 110a, 210a .. Substrate 110b, 210b ... 1st frame 110c, 210c ... 2nd frame 111, 211 ... Electrode pad 112, 212 ... External terminal 113, 213: Wiring pattern 114, 214: Via conductor 115, 215: Convex part 116, 216: Protrusive part 117, 217: Connection pad 118, 218: Connection pattern 119, 219 ··· Conducting pattern for sealing 120 ··· Crystal element 121 ··· Crystal base plate 122 ··· Excitation electrode 123 ··· Extraction electrode 130 ··· Lid body 131 ··· Bonding member 140 · · · · Conductive adhesive 150 ··· Temperature-sensitive element 151 · · · Connection terminal K1 ··· First recess K2 ··· Second recess C · · · Corner portion

Claims (9)

A rectangular substrate,
A first frame provided on the upper surface of the substrate;
A second frame provided on the lower surface of the substrate;
A pair of electrode pads provided on the upper surface of the substrate in a first recess formed by the substrate and the first frame;
A pair of connection pads provided on the lower surface of the substrate in the second recess formed by the substrate and the second frame;
External terminals provided at four corners of the lower surface of the second frame;
A crystal element mounted on the electrode pad;
A temperature sensitive element mounted on the connection pad via a conductive bonding material;
A lid joined to an upper surface of the first frame;
The shape of the opening of the second recess is a polygonal shape in plan view,
The corner of the opening of the second recess is provided so as to be located between the adjacent external terminals in plan view ,
The crystal oscillator according to claim 1, wherein four external terminals located near an oblique side connecting two corners of the opening of the second concave portion are chamfered at positions facing the oblique side . The crystal unit according to claim 1, wherein
A quartz oscillator characterized in that a shape of an opening of the second concave portion is octagonal in plan view. The crystal unit according to claim 1, wherein
The corner of the opening of the second concave portion is arc-shaped in plan view. The crystal unit according to any one of claims 1 to 3, wherein
The temperature-sensitive 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-sensitive element are mounted on the substrate. Crystal oscillator. A quartz oscillator according to any one of claims 1 to 4, wherein
The electrode pad is provided adjacent to one side of the inner peripheral edge of the first frame,
A quartz oscillator characterized in that one of the connection pads is located between the pair of electrode pads in plan view. The crystal unit according to any one of claims 1 to 5, wherein
The wiring pattern is electrically connected to the electrode pad, and is provided at a position overlapping the first frame when viewed in a plan view. The crystal unit according to claim 6, wherein
A part of the wiring pattern is provided so as to extend from the electrode pad in the direction of the long side of the first frame and to be exposed. The crystal unit according to any one of claims 1 to 7, wherein
The electrode pad is provided along one side of the substrate,
A crystal unit comprising a convex portion provided on the upper surface of the electrode pad. The crystal unit according to claim 8, wherein
A quartz oscillator comprising a projection provided along a side facing one side of the substrate.

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