JP2011018951A - Piezoelectric oscillator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a piezoelectric oscillator further reduced in size, while a piezoelectric vibrating piece and an IC chip are mounted therein without overlapping.SOLUTION: The piezoelectric oscillator 1 includes: a rectangular piezoelectric vibrating piece 2; a rectangular electronic component 3; a base 4 having an opening and an internal storage part formed therein; and a lid covering the opening of the base, and is hermetically sealed by covering the opening of the base with the lid. The piezoelectric vibrating piece and the electronic component are mounted on a bottom of the internal storage part of the base without overlapping, and one end part of the piezoelectric vibrating piece is electrically connected to a pair of electrode pads of the base via a conductive connection member D1. One or more of electrode patterns have: a first region 711 passing under a side of the other end part of the piezoelectric vibrating piece; and a second region 712 passing under a side orthogonal to the side of the other end part of the piezoelectric vibrating piece, and electrode patterns in the first regions have thick parts 713 formed so as to be thicker than those in other regions.

Description

  The present invention relates to a piezoelectric oscillator.

  Currently, a piezoelectric oscillator has a rectangular parallelepiped package that includes a base and a lid. Then, by joining the base and the lid, the electronic components such as the piezoelectric vibrating piece and the IC chip inside the package are hermetically sealed. The piezoelectric vibrating piece is electrically and mechanically bonded to the base via a conductive bonding material such as a conductive resin adhesive or a conductive bump, and the IC chip is bonded to the piezoelectric vibrating piece or the like by a method such as wire bonding or FCB. It is electrically connected to the base. Among such piezoelectric oscillators, in the piezoelectric oscillator disclosed in Patent Document 1, the piezoelectric resonator element and the electronic component such as an IC chip are arranged in the same plane in the cavity of the base without being laminated, and the main body casing. It is considered to suppress the height (thickness) of the film.

JP 2007-228295 A

  However, in the piezoelectric oscillator in which the piezoelectric vibrating piece and the IC chip are mounted without overlapping as in Patent Document 1, the piezoelectric vibrating piece mounting area, the IC chip mounting area, the piezoelectric vibrating piece and the IC are mounted for further miniaturization. At present, it is demanded that the electrode pattern forming region for connecting to the chip be configured without being enlarged.

  Therefore, in order to solve the above-described problems, an object is to provide a piezoelectric oscillator in which a piezoelectric vibrating piece and an IC chip that do not hinder downsizing are mounted without being superimposed.

  In order to achieve the above object, a rectangular piezoelectric vibrating piece, an electronic component, a base on which an opening and an internal storage portion are formed, and a lid that covers the opening of the base are provided. A piezoelectric oscillator comprising a lid and hermetically sealed, wherein the piezoelectric vibrating reed and the electronic component are mounted on the bottom surface of the internal storage portion of the base so as not to overlap each other, and one end of the piezoelectric vibrating reed The portion is electrically bonded to a pair of electrode pads on the base via a conductive bonding material, and the electrode pads are drawn out to the electronic component by an electrode pattern for internal connection, and the piezoelectric vibrating piece and the electronic component are electrically connected to each other. The external terminal is drawn out by an electrode pattern for external connection, and one or more of the electrode pattern for internal connection and the electrode pattern for external connection are at the other end of the piezoelectric vibrating piece. Pass under the side A second region in which one or more of the electrode pattern for internal connection and the electrode pattern for external connection pass under a side perpendicular to the side of the other end of the piezoelectric vibrating piece; It is characterized by having.

  According to the configuration of the present invention, the mounting position of the piezoelectric vibrating piece and the electronic component is brought close to each other by mounting the piezoelectric vibrating piece and the electronic component on the bottom surface portion of the internal storage portion of the base so as not to overlap each other. In addition, since the connection lines (wiring patterns, etc.) can be shortened from each other, a piezoelectric oscillator with higher performance without the influence of unnecessary noise can be obtained. Since it is not necessary to interpose a conductive member such as a via in the thickness direction, the configuration is advantageous for reducing the height.

  One end portion of the piezoelectric vibrating piece is cantilevered and electrically and mechanically bonded to a pair of electrode pads on the base via a conductive bonding material, so that the excitation area of the piezoelectric vibrating piece is set wider and in series. The resonance resistance can be improved and the frequency variable amount can be widened. Further, by holding the cantilever, the holding area of the piezoelectric vibrating piece can be reduced.

  A first region in which one or more of the electrode pattern for internal connection and the electrode pattern for external connection pass under a side of the other end of the piezoelectric vibrating piece; the electrode pattern for internal connection; Since one or more of the electrode patterns for external connection have a second region that passes under a side orthogonal to the other end of the piezoelectric vibrating piece, the first region is cantilevered. It is possible to function as a pillow region that regulates the inclination of the other end of the piezoelectric vibrating piece, and simultaneously serves as an auxiliary pillow region that suppresses bending of the piezoelectric vibrating piece that occurs after contacting the second region with the pillow region. Can function.

  For example, when one end portion of the piezoelectric vibrating piece is cantilever-supported, for example, via a paste of conductive bonding material, the free end side (the other end portion) of the piezoelectric vibrating piece is contracted by the shrinkage when the conductive bonding material is cured. And the free end side (side of the other end) and the first region (pillow region) of the electrode pattern may be slightly separated (close state) in a steady state. Even in such a state, the free end side of the piezoelectric vibrating reed and the first region (pillow region) of the electrode pattern only abut upon receiving an impact due to an external factor. There is no contact with the bottom surface of the internal storage portion of the base. In addition, when the free end side (side of the other end portion) of the piezoelectric vibrating piece comes into contact with the first region (pillow region) of the electrode pattern, bending occurs near the center of the one end portion and the other end portion of the piezoelectric vibrating piece. Even if this occurs, the side perpendicular to the side of the other end of the piezoelectric vibrating piece only comes into contact with the second area (auxiliary pillow area) of the electrode pattern, and the piezoelectric vibrating piece minimizes bending. Can be eliminated.

  In addition, the first region (pillow region) and the second region (auxiliary pillow region) of these electrode patterns are an electrode pattern for internal connection for connecting the piezoelectric vibrating piece and the electronic component or an external connection for connecting an external terminal. Since it is comprised at least one of the electrode patterns, it can comprise only an electrode pattern, without providing a separate separate member. As a result, it is not necessary to enlarge the area other than the electrode pattern formation area, and the mounting area of the internal storage portion of the base is not enlarged. Simplification and miniaturization of the configuration of the piezoelectric oscillator can be easily performed.

  In the present invention, in addition to the above-described configuration, the electrode pattern of the first region may have a thick portion formed thicker than the electrode patterns of other regions. In such a configuration, in addition to the above-described effects, the piezoelectric vibrating piece can be mounted in a state in which the inclination of the other end of the piezoelectric vibrating piece is further relaxed by the thick portion, so that the mounting stability of the piezoelectric vibrating piece is improved. . By eliminating the inclination of the piezoelectric vibrating piece, the excitation electrode of the piezoelectric vibrating piece does not come into contact with the internal storage portion of the base, and the excitation electrode is not damaged. Even a piezoelectric vibrating piece in which the center of the piezoelectric vibrating piece is processed to be thick, such as a bevel shape or a convex shape, can be stably mounted without the central portion of the piezoelectric vibrating piece coming into contact with the internal storage portion of the base. In addition, since such a thick portion is formed on the electrode pattern or is composed of the electrode pattern itself, it is not necessary to enlarge the region other than the electrode pattern formation region, and the mounting region of the internal storage portion of the base Does not expand.

  In the present invention, in addition to the above configuration, the electrode pattern may be drawn out without passing under the area where the excitation electrode of the piezoelectric vibrating piece is formed. In such a configuration, in addition to the above-described effects, the electrode pattern is drawn out at a position where it does not come into contact with the excitation electrode of the piezoelectric vibrating piece, and causes contact with the electrode pattern without damaging the excitation electrode, resulting in characteristic abnormality. There is no.

  In the present invention, in addition to the above configuration, the first region and the second region may be provided only by the electrode pattern for internal connection. In such a configuration, in addition to the above-described effects, the first region (pillow region) and the second region (auxiliary pillow region) are configured only by the electrode pattern for internal connection arranged close to the piezoelectric vibrating piece, and the piezoelectric vibration Since an electrode pattern for internal connection can be arranged around the piece, a more optimal pattern design can be performed without expanding the formation area of the electrode pattern, and a configuration desirable for further downsizing the internal storage portion of the base Become.

  According to the present invention, it is possible to provide a piezoelectric oscillator in which a piezoelectric vibrating piece and an IC chip that do not hinder downsizing are mounted without overlapping.

1 is a plan view showing a schematic configuration of a crystal oscillator according to Embodiment 1 of the present invention. FIG. 2 is a plan view before mounting the crystal vibrating piece and the IC chip of FIG. The top view which showed schematic structure of the crystal oscillator concerning the modification of Example 1 of this invention. The top view which showed schematic structure of the crystal oscillator concerning Example 2 of this invention. FIG. 5 is a plan view before the crystal vibrating piece and the IC chip of FIG. 4 are mounted. The top view which showed schematic structure of the crystal oscillator concerning Example 3 of this invention. FIG. 7 is a plan view before the crystal vibrating piece and the IC chip of FIG. 6 are mounted. Sectional drawing along the AA line of FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings, taking a surface-mounted crystal oscillator as an example of a piezoelectric oscillator. FIG. 1 is a plan view showing a schematic configuration of a crystal oscillator according to a first embodiment of the present invention, and FIG. 2 is a plan view before mounting the crystal resonator element and the IC chip of FIG. FIG. 3 is a plan view showing a schematic configuration of a crystal oscillator according to a modification of the first embodiment of the present invention. 4 is a plan view of a crystal oscillator according to a second embodiment of the present invention, and FIG. 5 is a plan view before the crystal resonator element and the IC chip of FIG. 4 are mounted. 6 is a plan view showing a schematic configuration of a crystal oscillator according to a third embodiment of the present invention, FIG. 7 is a plan view before the crystal resonator element and the IC chip of FIG. 6 are mounted, and FIG. FIG. 6 is a cross-sectional view taken along line AA in FIG. In addition, about the same part, the same number is attached | subjected partially and description is abbreviate | omitted.

  A crystal oscillator (piezoelectric oscillator) 1 according to an embodiment of the present invention includes a crystal vibrating piece (piezoelectric vibrating piece) 2, an IC chip (electronic component) 3 as an integrated circuit element, and a base 4 that arranges and holds them. The structure includes the crystal vibrating piece 2 bonded to the base 4 and held on the base 4 and a lid (not shown) for hermetically sealing the IC chip 3.

  In the crystal oscillator 1 of the first embodiment, a base and a lid are joined to form a main body casing (not shown), and as shown in FIGS. 1 and 2, the crystal vibration is placed on the base 4 inside the main body casing. The piece 2 and the IC chip 3 are arranged. At this time, a cavity 6 (internal storage portion) that is an arrangement region for arranging the crystal vibrating piece 2 and the IC chip 3 is formed inside the main body casing. The cavity 6 is an internal space of the base 4 hermetically sealed by a lid (not shown) and the base 4. The cavity 6 is provided with a bottom surface portion 61, and the crystal vibrating piece 2 and the IC chip 3 are arranged on the bottom surface portion 61 so as not to overlap each other.

  Next, each configuration of the crystal oscillator will be described.

  As shown in FIG. 1, the crystal vibrating piece 2 is formed of an AT-cut crystal piece and is formed into a single rectangular parallelepiped on a rectangular plan view. On both main surfaces of the quartz crystal resonator element 2, an excitation electrode 23, a connection electrode 24 for electrically connecting the excitation electrode 23 to an external electrode, and a lead for extracting the excitation electrode 23 to the connection electrode, respectively. An electrode 25 is formed. One end portion 21 of the quartz crystal vibrating piece 2 is formed of a pair of electrode pads 51 formed on the base 4 (the bottom surface portion 61 of the cavity 6) using a conductive adhesive D1 (conductive bonding material referred to in the present invention). Electromechanically joined to 52. The excitation electrode 23, the connection electrode 24, and the extraction electrode 25 are formed by a vacuum deposition method or a sputtering method. For example, from the quartz diaphragm side in the order of chromium and gold, or in the order of chromium, gold, and chromium, or chromium , Silver and chrome are laminated in this order. The conductive adhesive D1 used in this example is made of a conductive silicone resin having a curing temperature of about 180 degrees. Further, the conductive bonding material is not limited to the conductive silicone resin, and may be another resin such as a conductive urethane resin, or may be a metal bump such as gold.

  As shown in FIG. 1, the IC chip 3 is a one-chip integrated circuit element that constitutes an oscillation circuit together with the crystal vibrating piece 2, and a plurality of connection terminals 31 are formed on the bottom surface. In this embodiment, a bare chip is employed for the IC chip 3. The IC chip 3 is electrically connected to a plurality of electrode pads 53, 54, 55, 56, 57, 58 formed on the base 4 (bottom surface portion 61 of the cavity 6) through a metal bump B made of gold or the like by an FCB method or the like. Mechanically joined.

  The base 4 has a configuration in which a ceramic such as alumina and a conductive material such as tungsten are appropriately laminated. As shown in FIGS. 1 and 2, the base 4 is formed in a box-like body, and a conductive material having a predetermined shape and a ceramic material having a hollow shape are laminated on a single plate having a rectangular shape in plan view made of a ceramic material. Then, it is integrally fired in a substantially concave shape in cross section. Moreover, the ceramic material which has a hollow is shape | molded along the outer periphery of the surface of the ceramic material of the single plate rectangular shape planar view. The upper surface of the hollow ceramic material is a bonding region 43 (opening) with the lid, and a metallized layer for bonding with the lid is provided in the bonding region 43. A plurality of castellations C are formed on the outer periphery including the four corners of the base 4 in plan view. In the castellation, a semicircular cutout (semicircular recess) of the base 4 is formed from the front surface to the back surface of the main body housing. In this castellation, an electrode pattern (not shown) is formed.

As shown in FIGS. 1 and 2, an electrode pattern 71 for internal connection for electrically connecting the crystal vibrating piece 2 and the IC chip 3 to the bottom surface portion 61 of the cavity 6 that is the surface of the base 4. , 72 and external connection electrode patterns 73, 74, 75, 76 for electrically connecting external (external parts or external devices) electrodes. Specifically, as an electrode pattern for internal connection, an electrode pattern 71 for drawing out an electrode pad 51 bonded to the crystal vibrating piece 2 and an electrode pad 55 bonded to the connection terminal 2 of the IC chip 3, and a crystal vibrating piece 2 and an electrode pattern 72 for drawing out the electrode pad 54 bonded to the connection terminal of the IC chip 3 is formed. Further, as electrode patterns for external connection, an electrode pattern 73 for drawing out the connection terminal of the IC chip 3 to one of the external terminals, and an electrode pattern 74 for drawing out the connection terminal of the IC chip 3 to one of the external terminals; An electrode pattern 75 for drawing out the connection terminal of the IC chip 3 to one of the external terminals and an electrode pattern 76 for drawing out the connection terminal of the IC chip 3 to one of the external terminals are formed. These electrode patterns 71, 72, 73, 74, 75, 76 are drawn in a state where they do not pass under the region where the excitation electrode 23 of the hydroelectric vibrating piece 2 mounted on the base is formed. Although not shown, a plurality of external terminal electrodes that are connected (joined) to external (external parts or external devices) electrodes are formed on the back surface of the base 4. The external terminal electrodes include at least a Gnd electrode, an output electrode, an OE (Output Enable) electrode, a V _DD electrode, and the like.

  Of the thus formed internal connection electrode pattern and the external connection electrode pattern, the internal connection electrode pattern 71 passes under the side 221 of the other end 22 of the crystal vibrating piece 2. It has a first region 711 and a second region 712 that passes under a side 222 orthogonal to the side of the other end 22 of the crystal vibrating piece 2. Specifically, only the electrode pattern 71 passes from the electrode pad 51 along the periphery of the crystal vibrating piece 2 under the one long side 222 and the end of the short side 221 of the other end 22 to form a first L-shaped first. An area 711 and a second area 712 are configured. In a part of the first region 711, a film made of the same electrode pattern material is laminated in a rectangular shape to form a thick portion 713. When the electrode pattern 71 is formed by metallization, the thick part 713 of Example 1 is formed by laminating only the first region 711 with two or more metallization layers. The thickness difference of 30 μm or more can be ensured and the film can be formed thick. This electrode pattern 71 is finally drawn out to an electrode pad 55 to be joined to the connection terminal 2 of the IC chip 3. In the present embodiment, the first region 711, the second region 712, and the thick portion 713 are formed only in the region between the terminals connecting the electrode pad 51 and the electrode pad 55 in the electrode pattern 71. There is no need to enlarge the region other than the necessary formation region, and the configuration is desirable for simplifying and miniaturizing the electrode pattern.

  As described above, the crystal resonator element 2 and the IC chip 3 are connected (joined) to the outside (external parts or external devices) from the terminal electrodes. Such electrode pads 51, 52, 53, 54, 55, 56, 57, 58, electrode patterns 71, 72, 73, 74, 75, 76, and external terminal electrodes, for example, are metallized layers of tungsten or molybdenum ( Nickel plating and gold plating are formed on the upper portion of (not shown).

  The lid is made of a metal material, and a brazing material (not shown) is formed on the lower surface. The lid is joined to the base 4 by means of seam welding, beam welding, atmosphere heating, etc., and the body of the crystal oscillator comprising the lid and the base 4 A housing is molded. Specifically, the lid by seam welding has a single plate configuration in a rectangular shape in plan view in which a metal brazing material as a metal layer is formed on a core material made of Kovar. More specifically, for example, a nickel layer, Kovar core material from the upper surface , Copper layer and silver brazing layer. The silver brazing layer here is joined to the metallized layer of the base 2. Further, a part of the silver brazing layer is a welding region for joining with the metallized layer of the base 4, and this welding region is set along the outer peripheral end of the lid in plan view. The outer shape of the lid in plan view is substantially the same as or slightly smaller than the outer shape of the base 2.

  In the crystal oscillator 1 including the above-described constituent elements, the IC chip 3 and the crystal vibrating piece 2 are disposed in the cavity 6 of the base 4 and are electromechanically joined as described above. 2 is covered with a lid, and the metallized layer of the base 4 and a part of the silver brazing layer of the lid are melt-cured and bonded together, and the IC chip 3 and the crystal vibrating piece 2 in the cavity 6 are hermetically sealed.

  In addition to the one shown in the first embodiment, as shown in the modified example of FIG. 3A, only a part of the electrode pattern is formed along the periphery of the crystal vibrating piece 2 and the other end portion. A first region 711 in which only a part exists under one short side 221 of 22 and a second part in which only a part exists under one long side 222 orthogonal to the side of the other end 22 of the crystal vibrating piece 2. The area 712 may be configured. Specifically, a region in which a part of the electrode pattern 71 is wide is formed, and only this wide region passes under one long side 222 of the crystal vibrating piece 2 and one short side 221 end of the other end 22. The first area 711 and the second area 712 are configured. Similar to the above-described embodiment, a thick portion 713 is formed in a part of the wide first region 711 by laminating films made of the same electrode pattern material in a rectangular shape.

  3B, the first region is not limited to the one formed along the side 221 of the other end portion 22 of the crystal vibrating piece 2, but the corner portion of the crystal vibrating piece 2 The first region and the second region may be formed in separate electrode patterns. Specifically, the electrode pattern 71 includes first regions 7111 and 7112 that pass under regions close to the corner portions 2211 and 2122 at both ends of the side 221 of the other end portion 22 of the crystal vibrating piece 2, and the electrode pattern 72, a second region 722 that exists under the side 223 orthogonal to the side of the other end 22 of the crystal vibrating piece 2 is configured. Thick portions 7131 and 7132 are formed in a part of the first regions 7111 and 7112 by laminating films made of the same electrode pattern material in a rectangular shape.

  Further, as shown in the modification shown in FIG. 3C, the pair of electrode pads 51 and 52 for joining the one end portion 21 of the quartz crystal vibrating piece 2 are arranged at positions close to the IC chip 3 and the quartz crystal vibrating piece. 2 may be mounted by inverting 90 degrees with respect to the first embodiment. Specifically, a pair of electrode pads 51 and 52 for joining one end portion 21 of the quartz crystal vibrating piece 2 are disposed in the vicinity of the pair of electrode pads 55 and 54 joined to the connection terminal 2 of the IC chip 3. The electrode pattern 71 for internal connection that connects the electrode pads 51 and 55 includes a second region 712 that exists under the one long side 223 along the periphery of the crystal vibrating piece 2 from the electrode pad 51, and the crystal vibrating piece 2. A first region 711 passing under a region close to a corner portion 2212 at one end of one short side 221 of the other end portion 22 is formed, and a film made of the same electrode pattern material is rectangular in a part of the first region 711. A thick portion 713 is formed by being stacked in a shape. The electrode pattern 72 for internal connection for connecting the electrode pads 52 and 54 includes a second region 722 existing under one long side 222 from the electrode pad 52 along the periphery of the crystal vibrating piece 2, and the crystal vibrating piece 2. A first region 721 that passes under a region near the corner portion 2211 of the other end portion of the other short side 221 of the other end portion 22 is configured, and a film made of the same electrode pattern material is formed in a part of the first region 721. A thick portion 723 is formed in a rectangular shape. In this modification, the electrode patterns 71 and 72 are configured to be line symmetrical with respect to the virtual center line between the electrode patterns. For this reason, the capacitance by the electrode pattern for connecting the crystal vibrating piece 2 and the IC chip 3 is the same, which is a more desirable form that facilitates circuit design. In this modification, the lead distance by the electrode patterns 71 and 72 connecting the crystal resonator element 2 and the IC chip 3 is short, so that the parasitic capacitance is reduced and the oscillation margin as viewed from the crystal unit side is improved. This is especially advantageous for crystal oscillators for high frequencies of 100 MHz or higher.

  Further, as shown in the modification shown in FIG. 3D, the pair of electrode pads 51 and 52 for joining the one end portion 21 of the crystal vibrating piece 2 are disposed at positions separated from the IC chip 3, and the crystal vibrating piece 2 may be reversed by −90 degrees with respect to the first embodiment. Moreover, you may comprise by an insulating film as a thick part. Specifically, the pair of electrode pads 51 and 52 that join the one end portion 21 of the crystal vibrating piece 2 are arranged at positions separated from the pair of electrode pads 55 and 54 that are joined to the connection terminal 2 of the IC chip 3. The electrode pattern 71 for internal connection that connects the electrode pads 51 and 55 includes a second region 712 existing under one long side 222 from the electrode pad 51 along the periphery of the crystal vibrating piece 2, and the crystal vibrating piece 2. A first region 711 that passes along a region adjacent to the corner portion 2211 at one end of one short side 221 of the other end portion 22 is formed, and is finally connected to the electrode pad 55. In a part of the first region 711, an insulating film such as alumina is laminated in a rectangular shape to form a thick portion 713. The electrode pattern 72 for internal connection for connecting the electrode pads 52 and 54 includes a second region 722 existing under one long side 223 along the periphery of the crystal vibrating piece 2 from the electrode pad 52, and the crystal vibrating piece 2. A first region 721 is formed that passes so as to bend along a region near the corner portion 2212 at the other end of the other short side 221 of the other end 22, and is finally connected to the electrode pad 54. . An insulating film such as alumina is laminated in a rectangular shape in a part of the first region 721 to form a thick portion 723. In this modification, the electrode patterns 71 and 72 are configured to be line symmetrical with respect to the virtual center line between the electrode patterns. For this reason, the capacitance by the electrode pattern for connecting the crystal vibrating piece 2 and the IC chip 3 is the same, which is a more desirable form that facilitates circuit design. Moreover, in this modification, since the insulating film is laminated on the upper portions of the thick portions 713, 723, the electrode patterns 71, 72 are not electrically connected to the excitation electrode 23 formed on the crystal vibrating piece 2, There is no danger of a short circuit, and a configuration that does not lead to electrical oscillation can be achieved.

  According to the first embodiment, by mounting the crystal vibrating piece 2 and the IC chip 3 on the bottom surface portion 61 of the base 4 so as not to overlap each other, the mounting positions of the crystal vibrating piece 2 and the IC chip 3 can be brought close to each other. In addition, since the internal connection electrode patterns 71 and 72 which are connection lines can be shortened, a crystal oscillator having higher performance without the influence of unnecessary noise can be obtained.

  One end portion of the quartz crystal vibrating piece 2 is cantilevered and electrically and mechanically joined to the pair of electrode pads 51 and 52 of the base 4 through the conductive adhesive D1, so that the excitation electrode 23 of the quartz crystal vibrating piece 2 is connected. The region can be set wider, the series resonance resistance can be improved, and the frequency variable amount can be increased. Further, by holding the cantilever, the holding area of the crystal vibrating piece 2 can be reduced.

  The electrode pattern 71 for internal connection passes from the electrode pad 51 along the periphery of the quartz crystal vibrating piece 2 under the one long side 222 and the end of the short side 221 of the other end 22 to form a first L-shaped first. A region 711 and a second region 712 are configured, and a film made of the same electrode pattern material is laminated in a rectangular shape in a part of the first region 711 to form a thick portion 713. The quartz crystal vibrating piece that can be caused to function as a pillow region that regulates the inclination of the other end 22 of the quartz vibrating piece 2 in which the thick portion 713 is cantilevered, and that occurs after the second region 712 comes into contact with the pillow region 2 can function simultaneously as an auxiliary pillow region that suppresses the bending of 2. As a result, damage to the quartz crystal vibrating piece 2 can be eliminated and the shock resistance performance can be significantly improved. The thick part 713 (pillow region) and the second region 712 (auxiliary pillow region) of the first region 711 of these electrode patterns are electrode patterns 71 and 72 for internal connection or electrode patterns 73 and 74 for external connection. Since it is formed on at least one of the electrode patterns 75 and 76 or is composed of the electrode pattern itself, it is not necessary to enlarge the region beyond the region where the electrode pattern is formed, and the cavity 6 (inside The mounting area of the storage unit is not enlarged.

  In the first embodiment, since the electrode patterns 71 to 76 are drawn without passing under the area where the excitation electrode 23 of the crystal vibrating piece 2 is formed, the electrode patterns 71 to 76 are used to excite the crystal vibrating piece 2. It is pulled out at a position where it does not contact the electrode 23, and the excitation electrode 23 is not damaged. The excitation electrode 23 and the patterns 71 to 76 are not brought into contact with each other, thereby causing a characteristic abnormality.

  Further, in Example 1, the thick portion 713 (pillow region) and the second region 712 (auxiliary pillow region) of the first region 711 are configured only by the electrode pattern 71 for internal connection disposed in the vicinity of the crystal vibrating piece 2, Since the electrode pattern 71 for internal connection can be arranged around the crystal vibrating piece 2, more optimal pattern design can be performed without expanding the formation area of the electrode pattern 71, and the cavity 6 (internal storage portion) of the base 4. This is a desirable configuration for further downsizing.

  In the first embodiment, the thick portion 713 is formed by stacking the same electrode pattern film on the upper portion of the electrode pattern 711, so that a pillow region formed of the same material as the electrode pattern 71 and having a large thickness is integrally formed. Therefore, the pillow region can be easily and stably formed at any position and any region above the electrode pattern 71 without expanding the pillow region to other regions of the cavity 6 (internal storage portion) of the base 4. can do.

  In the first embodiment and the modification described above, the first region and the second region are provided only by the electrode patterns 71 and 72 for internal connection. Therefore, in the second embodiment shown in FIGS. 4 and 5, the first region is constituted by the electrode pattern 74 for external connection, and the second region is constituted by the electrode pattern 71 for internal connection. Specifically, the electrode pattern 74 includes a first region 741 that passes under one short side 221 end of the other end 22 of the crystal vibrating piece 2, and the electrode pattern 71 includes the crystal vibrating piece 2. 2nd area | region 712 which passes under the edge | side 222 orthogonal to the edge | side of the other end part 22 of this is comprised. The electrode pattern 71 passes from the electrode pad 51 under the one long side 222 along the periphery of the quartz crystal vibrating piece 2, passes under the excitation electrode 23 formation region, and between the electrode pattern 74 to the electrode pad 55. It has been extended. In a part of the first region 741, an insulating film such as alumina is laminated in a rectangular shape to form a thick portion 743. In addition, the same structure as the said Example attaches | subjects the same number, and abbreviate | omits detailed description.

  According to the second embodiment, the first region is configured by the electrode pattern 74 for external connection, and the second region is configured by the electrode pattern 71 for internal connection. Specifically, a first region 741 that passes under one short side 221 end of the other end 22 of the crystal vibrating piece 2 is constituted by the electrode pattern 74 for external connection, and the electrode pattern 71 for internal connection A second region 712 that passes under a side 222 orthogonal to the side of the other end portion 22 of the crystal vibrating piece 2 is configured, and an insulating film such as alumina is laminated in a rectangular shape in a part of the first region 741. Since the thick portion 743 is formed, the thick portion 743 of the first region 741 can be functioned as a pillow region that regulates the position of the other end portion 22 of the crystal vibrating piece 2 that is cantilevered. The two regions 712 can simultaneously function as an auxiliary pillow region that suppresses the bending of the crystal vibrating piece 2 that occurs after contacting the pillow region. As a result, damage to the quartz crystal vibrating piece 2 can be eliminated and the shock resistance performance can be significantly improved. The thick part 743 (pillow region) and the second region 712 (auxiliary pillow region) of the first region 741 of these electrode patterns are electrode patterns 71 and 72 for internal connection or electrode patterns 73 and 74 for external connection. Since it is formed on at least one of the electrode patterns 75 and 76, or is composed of the electrode pattern itself, it is not necessary to enlarge it beyond the region where the electrode pattern is formed, and the cavity 6 (internal) The mounting area of the storage unit is not enlarged. In the configuration in which the plurality of electrode patterns 71 and 74 pass under the crystal vibrating piece 2 in parallel as in the second embodiment, the electrode pattern 74 located in the first region is formed thicker than the other electrode pattern 71. Thus, it is desirable that the electrode pattern 71 and the quartz crystal vibrating piece 2 are not in contact with each other.

  In the second embodiment, since the electrode patterns 71 to 76 are drawn without passing under the area where the excitation electrode 23 of the crystal vibrating piece 2 is formed, the electrode patterns 71 to 76 are used to excite the crystal vibrating piece 2. It is pulled out at a position where it does not contact the electrode 23, and the excitation electrode 23 is not damaged. The excitation electrode 23 and the patterns 71 to 76 are not brought into contact with each other, thereby causing a characteristic abnormality.

  In the second embodiment, the thick portion 743 is not electrically connected to the excitation electrode 23 formed on the crystal vibrating piece 2 because the insulating film is laminated on the upper portion of the electrode pattern 74. There is no danger. Such a pillow region does not expand to other regions of the cavity 6 (internal storage portion) of the base 4, and forms a pillow region easily and stably at an arbitrary position on the electrode pattern 74 and at an arbitrary region. be able to.

  The crystal oscillator 1 of the third embodiment is different from the above-described embodiment in that the electrical connection of the IC chip is performed by wire bonding. Accordingly, the configuration of the base cavity (internal storage portion) 6 is also different. Is different. That is, as shown in FIGS. 6, 7, and 8, the cavity 6 is provided with a bottom surface portion 61 and a second bottom surface portion 62 that is an upper layer than the bottom surface portion 61. The IC chips 3 are arranged on the bottom surface portion 61 so as not to overlap each other on the bottom surface portion 61, and the wires W connected to the IC chip 3 are connected on the second bottom surface portion 62. Hereinafter, only the components unique to the third embodiment will be described, and the same components as those in the above-described embodiment will be denoted by the same reference numerals and a part of the description will be omitted.

  As shown in FIG. 6, one end portion 21 of the quartz crystal vibrating piece 2 is formed on the base 4 (the second bottom surface portion 62 of the cavity 6) using a conductive adhesive D <b> 1 (conductive bonding material in the present invention). Electromechanically bonded to the pair of electrode pads 51 and 52.

  As shown in FIG. 6, the IC chip 3 is a one-chip integrated circuit element that forms an oscillation circuit together with the crystal vibrating piece 2, and a plurality of connection terminals 31 are formed on the upper surface. In this embodiment, a bare chip is employed for the IC chip 3. The IC chip 3 is mechanically bonded to the base 4 (the bottom surface portion 61 of the cavity 6) by a highly curable bonding material D2. In this embodiment, a polyimide resin having a curing temperature of about 290 degrees is used as the highly curable bonding material D2. In addition, a polyimide resin is preferable as the highly curable bonding material D2, but is not limited to the polyimide resin, and may be an epoxy resin (silver paste). The plurality of connection terminals 31 of the IC chip 3 are formed of a plurality of electrode pads 53, 54, 55, 56, 57 formed on the base 4 (second bottom surface portion 62 of the cavity 6) using a wire W such as gold. , 58 are electrically connected. Note that unlike the third embodiment, the crystal vibrating piece 2 and the IC chip 3 are not overlapped, and a stepped portion (a step formed by the bottom surface portion 61 and the second bottom surface portion 62) is formed between the crystal vibrating piece 2 and the IC chip 3. In the crystal oscillator having (), the upper surface position of the second bottom surface portion 62 of the cavity 6 of the base 4 is preferably lower than the upper surface position of the IC chip 3. That is, as shown in FIG. 8, the upper surface position of the second bottom surface portion 62 is lower than the upper surface position of the IC chip 3 in consideration of the thickness of the bottom surface portion 61 and the second bottom surface portion 62 in consideration of the thickness of the IC chip. With this configuration, the product height of the entire crystal oscillator can be set low, which is a preferable form for implementation. In the embodiment as in the third embodiment, it is more desirable to consider the height of the apex of the wire W. That is, the apex position of the wire W is configured to be higher than the lower surface position of the crystal vibrating piece 2.

As shown in FIGS. 6 and 7, an internal connection electrode for electrically connecting the crystal vibrating piece 2 and the IC chip 3 is provided on the second bottom surface portion 62 of the cavity 6 which is the surface of the base 4. External connection electrode patterns 73, 74, 75, 76 for electrically connecting the patterns 71, 72 and external (external parts or external devices) electrodes are formed. These electrode patterns 71, 72, 73, 74, 75, 76 are drawn in a state where they do not pass under the region where the excitation electrode 23 of the hydroelectric vibrating piece 2 mounted on the base is formed. Although not shown, a plurality of external terminal electrodes that are connected (joined) to external (external parts or external devices) electrodes are formed on the back surface of the base 4. The external terminal electrodes include at least a Gnd electrode, an output electrode, an OE (Output Enable) electrode, a V _DD electrode, and the like.

  Of the thus formed internal connection electrode pattern and the external connection electrode pattern, the internal connection electrode pattern 71 passes under the side 221 of the other end 22 of the crystal vibrating piece 2. It has a first region 711 and a second region 712 that passes under a side 222 orthogonal to the side of the other end 22 of the crystal vibrating piece 2. Specifically, only the electrode pattern 71 passes from the electrode pad 51 along the periphery of the crystal vibrating piece 2 under the one long side 222 and the end of the short side 221 of the other end 22 to form a first L-shaped first. An area 711 and a second area 712 are configured. This electrode pattern 71 is finally drawn out to an electrode pad 55 to be joined to the connection terminal 2 of the IC chip 3.

  As described above, the crystal resonator element 2 and the IC chip 3 are connected (joined) to the outside (external parts or external devices) from the terminal electrodes. Such electrode pads 51, 52, 53, 54, 55, 56, 57, 58, electrode patterns 71, 72, 73, 74, 75, 76, and external terminal electrodes, for example, are metallized layers of tungsten or molybdenum ( Nickel plating and gold plating are formed on the upper portion of (not shown).

  In the crystal oscillator 1 including the above-described constituent elements, the IC chip 3 and the crystal vibrating piece 2 are disposed in the cavity 6 of the base 4 and are electromechanically joined as described above. 2 is covered with a lid, and the metallized layer of the base 4 and a part of the silver brazing layer of the lid are melt-cured and bonded together, and the IC chip 3 and the crystal vibrating piece 2 in the cavity 6 are hermetically sealed.

  By mounting the crystal vibrating piece 2 on the second bottom surface portion 62 of the base 4 and the IC chip 3 on the bottom surface portion 61 so as not to overlap each other, the crystal vibrating piece 2 and the IC chip 3 are mounted. Since the positions can be close to each other and the internal connection electrode patterns 71 and 72 which are connection lines can be shortened, a crystal oscillator having higher performance without the influence of unnecessary noise can be obtained.

  One end portion of the quartz crystal vibrating piece 2 is cantilevered and electrically and mechanically joined to the pair of electrode pads 51 and 52 of the base 4 through the conductive adhesive D1, so that the excitation electrode 23 of the quartz crystal vibrating piece 2 is connected. The region can be set wider, the series resonance resistance can be improved, and the frequency variable amount can be increased. Further, by holding the cantilever, the holding area of the crystal vibrating piece 2 can be reduced.

  The electrode pattern 71 for internal connection passes from the electrode pad 51 along the periphery of the quartz crystal vibrating piece 2 under the one long side 222 and the end of the short side 221 of the other end 22 to form a first L-shaped first. Since the region 711 and the second region 712 are configured, the first region 711 can be functioned as a pillow region for regulating the position of the other end 22 of the crystal vibrating piece 2 that is cantilevered. The region 712 can simultaneously function as an auxiliary pillow region that suppresses the bending of the crystal vibrating piece 2 that occurs after contacting the pillow region. As a result, damage to the quartz crystal vibrating piece 2 can be eliminated and the shock resistance performance can be significantly improved. The first region 711 (pillow region) and the second region 712 (auxiliary pillow region) of these electrode patterns are at least one of the electrode patterns 71 and 72 for internal connection or the electrode patterns 73, 74, 75, and 76 for external connection. Since it is composed of one electrode pattern itself, it is not necessary to enlarge the region other than the electrode pattern formation region, and the mounting region of the cavity 6 (internal storage portion) of the base 4 is not enlarged.

  In the third embodiment, since the electrode patterns 71 to 76 are drawn without passing under the region where the excitation electrode 23 of the crystal vibrating piece 2 is formed, the electrode patterns 71 to 76 are used to excite the crystal vibrating piece 2. It is pulled out at a position where it does not contact the electrode 23, and the excitation electrode 23 is not damaged. The excitation electrode 23 and the patterns 71 to 76 are not brought into contact with each other, thereby causing a characteristic abnormality.

  In the third embodiment, the first region 711 (pillow region) and the second region 712 (auxiliary pillow region) are configured only by the internal connection electrode pattern 71 disposed in the vicinity of the crystal vibrating piece 2. Since the electrode pattern 71 for internal connection can be arranged around the periphery, more optimal pattern design can be performed without expanding the formation area of the electrode pattern 71, and the cavity 6 (internal storage portion) of the base 4 can be further downsized. This is a desirable configuration.

  Note that the first region and the second region in each of the above embodiments may be formed at a plurality of locations, and the second region may be formed on both of the two long sides 222 and 223. In each of the above embodiments, the electrode patterns 71, 72, 73, 74, 75, and 76 are drawn out without passing under the region where the excitation electrode 23 of the hydroelectric vibrating piece 2 mounted on the base is formed. However, if the electrode patterns arranged opposite to the excitation electrode 23 have the same potential, the electrode pattern may be drawn out under the region where the excitation electrode 23 of the crystal vibrating piece 2 is formed. Good. In such a configuration, the excitation electrode 23 formed on the crystal vibrating piece 2 is not electrically connected to the electrode pattern due to an impact caused by an external factor, and there is no danger of a short circuit. However, the oscillation is not electrically stopped.

  The present invention can be implemented in various other forms without departing from the spirit, the gist, or the main features of the present invention. For this reason, the above-described embodiment is merely an example in all respects and should not be interpreted in a limited manner. The scope of the present invention is indicated by the claims, and is not restricted by the text of the specification. Further, all modifications and changes belonging to the scope of the claims are within the scope of the present invention.

  The present invention can be applied to a piezoelectric oscillator such as a crystal oscillator.

DESCRIPTION OF SYMBOLS 1 Surface mount type crystal oscillator 2 Crystal vibrating piece 3 IC chip 4 Base D1 Conductive adhesive D2 High hardening bonding material W Wire

Claims (4)

It has a rectangular piezoelectric vibrating piece, an electronic component, a base on which an opening and an internal storage portion are formed, and a lid that covers the opening of the base, and the base opening is covered with a lid and hermetically sealed. A piezoelectric oscillator comprising:
The piezoelectric vibrating piece and the electronic component are mounted on the bottom surface of the internal storage portion of the base so as not to overlap each other, and one end of the piezoelectric vibrating piece is attached to a pair of electrode pads of the base via a conductive bonding material. Electrically joined and
The electrode pad is drawn out to an electronic component by an electrode pattern for internal connection, and the piezoelectric vibrating piece and the electronic component are electrically connected to each other,
The external terminal is drawn out by the electrode pattern for external connection,
A first region in which one or more of the electrode pattern for internal connection and the electrode pattern for external connection pass under a side of the other end of the piezoelectric vibrating piece; the electrode pattern for internal connection; One or more of the electrode patterns for external connection have a 2nd area | region which passes under the edge | side orthogonal to the edge | side of the other end part of a piezoelectric vibrating piece, The piezoelectric oscillator characterized by the above-mentioned. 2. The piezoelectric oscillator according to claim 1, wherein the electrode pattern of the first region has a thick part formed thicker than the electrode patterns of other regions.   3. The piezoelectric oscillator according to claim 1, wherein the electrode pattern is drawn out so as not to pass under a region where the excitation electrode of the piezoelectric vibrating piece is formed.   4. The piezoelectric oscillator according to claim 1, wherein the first region and the second region are provided only by the electrode pattern for internal connection. 5.

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