JP2006129290A - Small-sized crystal oscillator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a small-sized crystal oscillator structure in which problems can be solved which are caused by minimizing the outer shape of a crystal vibrator and consequent reduction in the inner volume thereof. <P>SOLUTION: A crystal oscillator 24 is configured by mounting a semiconductor component on a crystal vibrator 25 in which a vibrating portion 1 of a thin crystal blank and a reinforced portion of a thick crystal blank surrounding the vibrating portion are integrated and which performs thickness-shear vibration of AT cut, wherein in the crystal vibrator 25 where main electrodes are formed on both principal surfaces of the vibrating portion 1 and connecting electrodes extending from the main electrodes are formed, a surface 8, at the side of the crystal vibrator, of at least one plate-like container 7 facing the vibrating portion 1 is worked to be recessed, at the same time, between the container 7 and a crystal blank 3, a surface of a semiconductor component 27 packaged in the crystal vibrator 25 air-tightly sealed by filling the connecting electrodes with low fusing point metals 10 is covered with an insulated resin coating 26. Furthermore, the crystal blank 3 held between plate-like containers 7 of the crystal vibrator 25 comprising the crystal oscillator 24 is overcoated with insulating materials on the lateral side of the crystal vibrator 25. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

          The present invention is a small-sized semiconductor component mounted on an AT-cut thickness-shear vibration crystal unit in which a vibrating part of a quartz base plate thin plate and a reinforcing part of a quartz base plate thick plate surrounding it are integrated. The present invention relates to the structure of a crystal oscillator.

          In recent years, for example, as shown in the schematic side view of the crystal oscillator shown in FIG. 5, a crystal resonator is formed by placing a crystal base plate made of crystal on a conductive pad on an insulating substrate inside a crystal resonator container. In general, the connection electrode of the quartz base plate is hermetically sealed with a support structure in a cantilevered state with a conductive adhesive.

          The recent trend is that there is a very rapid demand for miniaturization and low profile from the market, as well as weight reduction and price reduction, with the transmission system in the communication field as the core. For this purpose, the crystal unit has a crystal structure in which the above-mentioned crystal element plate is supported in a cantilevered state inside the crystal unit container, and the lid is hermetically sealed. As for the external dimensions of the child, the external dimensions of the quartz base plate mounted inside the container with the bottomed recess are very small, and the external dimensions of the crystal unit using these small crystal base plates In fact, for example, a very small crystal resonator of 2.5 mm (H) × 2 mm (W) × 0.45 mm (D) is manufactured.

JP 2003-046337 A

          In addition, the applicant has not found any prior art documents related to the present invention by the time of the filing of the application other than the prior art documents specified by the prior art document information described above.

          However, as described above, as the crystal resonator is reduced in size and the inner volume thereof is reduced accordingly, the open end of the crystal base plate facing the end of the crystal base plate held by the conductive adhesive, The space between the quartz resonator lid and the inner wall including the inside of the container is also reduced. As a result, if an insulating substrate made of ceramic or the like on which the quartz resonator is mounted is distorted, the quartz base plate is mounted. Since the container of the crystal unit is also deformed, the open end of the above-described crystal unit plate mounted inside the crystal unit is the inner wall of the crystal unit, particularly the insulating substrate below the crystal unit plate and the crystal unit plate. There was a problem that there was a possibility of contacting the inner surface of the lid placed on the upper side.

          Further, as described above, when the external shape of the crystal resonator is reduced to, for example, 2.5 mm (H) × 2.0 mm (W) × 0.45 mm (D), the inner volume of the container is reduced accordingly. Of course, the quartz base plate, the lid, and the crystal unit container itself are also downsized, making it difficult to handle. As a result, semiconductor components are mounted on such crystal units. There was a problem that the manufacturing cost of the crystal oscillator having the above-described structure was high.

          In addition, when the internal volume of the crystal unit container becomes smaller and the quartz plate mounted in it becomes smaller and thinner, the frequency is determined by the thickness of the quartz plate made of quartz. There is a problem that it becomes difficult to mount the crystal element inside the crystal unit container, and as a result, it is difficult to manufacture a crystal oscillator in which a semiconductor component is mounted on such a low frequency crystal unit.

          The present invention has been made under the technical background as described above. Therefore, the object of the present invention is to vibrate the quartz base plate thin plate and the reinforcing portion of the quartz base plate thick plate surrounding it. Is to provide a small crystal oscillator with a semiconductor component mounted on an AT-cut quartz crystal resonator that performs thickness-slip vibration.

          In order to achieve the above object, the present invention provides an AT-cut thickness-shear vibration crystal unit in which a vibrating part of a quartz base plate thin plate and a reinforcing part of a quartz base plate thick plate surrounding the quartz base plate are integrally formed. In a crystal oscillator configured by mounting a semiconductor component, a crystal vibration in which main electrodes are formed on both main surfaces of the vibration part of the quartz base plate thin plate of the crystal resonator and a connection electrode extending from the main electrode is formed The surface of the quartz resonator side of at least one plate-like container facing the vibrating portion of the previous quartz base plate thin plate is recessed, and the gap between the plate-like vessel and the quartz base plate is low at the previous connection electrode. A surface of a semiconductor component mounted on a quartz resonator that is filled with a melting point metal and hermetically sealed is covered with an insulating resin film.

          In addition, a quartz base plate sandwiched between plate-like containers of the crystal unit constituting the crystal oscillator is overcoated on the side surface of the crystal unit with an insulating material.

          According to the structure of the crystal oscillator of the present invention, it is possible to manufacture a crystal oscillator with a high yield while suppressing the production cost of a small crystal oscillator.

          In addition, according to the structure of the crystal oscillator of the present invention, it is necessary to make the external size of the crystal element plate of the crystal resonator, which is a component, much smaller than the container size like a conventional cantilever crystal resonator. As a result, the container can be made as large as a quartz base plate, thereby obtaining a sufficient mounting area for semiconductor components.

          In addition, according to the structure of the crystal oscillator of the present invention, the structure can be remarkably simplified as compared with the conventional structure, so that a highly reliable crystal resonator can be manufactured at a low production cost. In addition, it is possible to manufacture a crystal oscillator capable of obtaining a low oscillation frequency of several MHz.

          Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In addition, the same code | symbol in each figure shall show the same object.

          FIG. 1 is a schematic side view of an embodiment as seen from the longitudinal side surface direction of the crystal base plate 3 so that the shape of the crystal base plate 3 inside the crystal resonator 25 which is a component of the crystal oscillator 24 of the present invention can be seen. It is a schematic diagram. That is, the shape of the crystal base plate 3 inside the crystal unit 25 which is a component of the crystal oscillator 24 of the present invention is the vibrating portion 1 of the crystal base plate thin plate and the reinforcing portion 2 of the crystal base plate thick plate surrounding the periphery. Has a crystal base plate 3 of a shape integrally formed. Although exaggerated in the figure, the plate-like container surface 8 on the crystal element plate 3 side of the plate-like container 7 facing the vibration surface of the crystal element plate 3 is recessed as shown in the concave processing portion 9 in the figure. Has been processed. This concave processing is formed in order to protect the vibration of the vibrating portion 1 of the thin plate of the quartz base plate 3 without being disturbed by the contact with the plate-like container 7. The space between the plate-like container 7 and the quartz base plate 3 is hermetically sealed with a low melting point metal layer 10. In this figure, the state in which the output of the semiconductor component 27 covered with the insulating resin film 26 is conducted to the external terminal 14 of the crystal oscillator 24 through the through holes 28 and the bumps that penetrate the plate-like container 7 made of, for example, ceramic. It is shown. In the crystal oscillator 24 of this figure, a semiconductor component 27 covered with an insulating resin film 26 is placed on a crystal resonator 25 in which a crystal base plate 3 is sandwiched between two plate-like containers 7 made of two ceramic substrates. It is an installed configuration. In the case of the structure of the crystal oscillator 24, the internal crystal base plate 3 is held in the horizontal direction with respect to the mounting substrate 20 on which the crystal oscillator 24 is mounted.

          FIG. 2 is a schematic side view of another embodiment of the crystal oscillator 24 according to the present invention as viewed from the longitudinal side surface direction of the crystal base plate 3 sandwiched between the plate-like containers 7 of the crystal resonator 25 which is a component thereof. FIG. The peripheral side surface of the quartz oscillator 25 inside the dotted line enclosure in the center of the figure is thinly overcoated 19 (film) with a heat-resistant resin or the like so as to cover the end face of the quartz base plate 3. The overcoat 19 is formed to protect the end face of the quartz base plate 3 sandwiched between the plate-like containers 7. In the case of this structure, the internal quartz base plate 3 is held in a direction perpendicular to the mounting substrate 20 to be mounted. Further, the crystal oscillator 24 of this figure is a semiconductor component 27 covered with an insulating resin film 26 on a crystal resonator 25 in which a crystal base plate 3 is sandwiched between plate-like containers 7 each consisting of two ceramic substrates of a plurality of layers. It is the configuration where is mounted.

          FIG. 3 is a schematic top view of the crystal element plate 3 of the crystal resonator 25, which is a component of the crystal oscillator 24 of the present invention, as viewed from above the main surface. The quartz base plate 3 is formed by integrating a vibrating portion 1 of a quartz base plate thin plate and a reinforcing portion 2 of a quartz base plate thick plate surrounding the quartz base plate, and a central round portion is a main electrode 5 extending from the main portion. A connection electrode 6 is formed inside the quartz base plate 3 along the outer shape thereof. The outer end 15 of the connection electrode 6 is preferably located inside the main surface outer end 16 of the quartz base plate 3. By using the crystal resonator 25 using the crystal base plate 3 as shown in the figure as a component, a small crystal oscillator 24 having a structure that is remarkably simple as compared with the prior art can be manufactured at a reduced manufacturing cost. I can do it.

          FIG. 4 is a schematic external perspective view showing an embodiment of the crystal oscillator 24 of the present invention. The quartz base plate 3 is sandwiched between plate-like containers 7, and the peripheral side surface thereof is overcoated 19 for protecting the end face of the quartz base plate 3. A semiconductor component 27 is mounted on the upper surface of the crystal oscillator 24, an insulating resin film 26 is formed thereon, and an external terminal 14 is provided on the lower surface.

          FIG. 5 is a schematic side view schematically showing a crystal oscillator 24 having a conventional crystal cantilever support structure 25 having a cantilever support structure as viewed from the longitudinal side surface of the crystal base plate 3 inside the crystal oscillator 25. It is.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic side view of an embodiment of a crystal oscillator according to an embodiment of the present invention viewed from a longitudinal side surface direction of a crystal element plate so that a shape of a crystal element plate inside a crystal resonator that is a component thereof can be understood. FIG. 5 is a schematic side view of another embodiment of the crystal oscillator of the present invention as viewed from the longitudinal side surface direction of a crystal base plate sandwiched between plate-shaped containers of crystal resonators that are constituent parts thereof. FIG. 3 is a schematic top view of a crystal base plate of a crystal resonator, which is a component of the crystal oscillator of the present invention, viewed from above the main surface. 1 is a schematic external perspective view showing an embodiment of a crystal oscillator according to the present invention. It is the schematic diagram which looked at the crystal oscillator which uses the crystal resonator with the conventional general cantilever support structure as a component from the longitudinal direction side surface of the crystal base plate inside a crystal resonator.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Crystal base plate thin plate vibration part 2 Crystal base plate thick plate reinforcement part 3 Crystal base plate 5 Main electrode 6 Connection electrode 7 Plate-shaped container 8 Plate-shaped container surface 9 on the crystal unit side Recessed processing part 10 Low melting point metal layer 14 External terminal 15 External end 16 of connection electrode Main surface external end 19 of crystal resonator Overcoat (part)
20 mounting substrate 22 container 23 lid 24 crystal oscillator 25 crystal oscillator 26 insulating resin film 27 semiconductor component 28 through hole

Claims (2)

A crystal oscillator that consists of an AT-cut quartz crystal resonator that vibrates and vibrates an AT-cut thick plate that surrounds the quartz crystal plate thin plate and a reinforcing part that surrounds it. In
A main electrode is formed on both main surfaces of the vibrating portion of the quartz base plate thin plate of the quartz resonator, and the quartz resonator having a connection electrode extending from the main electrode is connected to the vibrating portion of the quartz base plate thin plate. The quartz crystal side surface of at least one of the plate-like containers facing the quartz is recessed, and the connection electrode is filled with a low-melting-point metal between the plate-like container and the crystal base plate and hermetically sealed. A crystal oscillator characterized in that the surface of the semiconductor component mounted on the vibrator is covered with an insulating resin film.           2. The crystal base plate sandwiched between the plate-like containers of the crystal resonator constituting the crystal oscillator is overcoated on the side surface of the crystal resonator with an insulating material. Crystal oscillator.

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