JP4890914B2 - Support structure of quartz crystal resonator element - Google Patents

Description

The present invention relates to a support structure for a crystal vibrating piece in which various electrodes are formed on a crystal base plate.

  A crystal vibrating piece 51 used for a crystal resonator 50 which is one of electronic components accommodates an excitation electrode 53 for exciting the crystal element plate 52 and the crystal vibrating piece 51 on the front and back main surfaces of the crystal element plate 52. The connection electrode 54 for connecting to the support portion 57 formed in the base container 56 and the extraction electrode 55 for electrically connecting the excitation electrode 53 and the connection electrode 54 are formed. With the miniaturization of the crystal unit 50, a small strip shape has become mainstream as the crystal base plate 52 shape. In order to cope with further downsizing, conventionally, a conductive adhesive member 58 has been used as a conductive fixing means between the extraction electrode 55 on the quartz-crystal vibrating piece 51 side and the support portion 57 on the base container 56 side.

  FIG. 5 is a cross-sectional view of a crystal resonator 50 showing a state in which a crystal vibrating piece 51 having various electrodes formed therein is housed in a base container 56 and conductively fixed by a conductive adhesive member 58 as an example of the prior art. That is, on the front and back main surfaces of the crystal element plate 52 constituting the crystal resonator element 51, opposed excitation electrodes 53 and connection electrodes extending from the excitation electrode 53 to one short side of the crystal element plate 52. 54 and a lead-out electrode 55 that is electrically connected to the connection electrode 54 and is electrically connected to the support portion 57 on the base container 56 side is formed.

The quartz crystal vibrating piece 51 configured as described above is disposed in the space of the base container 56 so as to be substantially parallel to the bottom surface inside the base container 56. At that time, a conductive connection is made between the extraction electrode 55 on the crystal vibrating piece 51 side and the support portion 57 on the base container 56 side by a conductive adhesive member 58 made of a metal material such as gold. The conductive adhesive member 58 also holds the crystal vibrating piece 51 in the posture inside the base container 56. The crystal resonator 50 is formed by disposing a metal lid 59 in the opening of the base container 56 in which the crystal vibrating piece 51 is mounted in the internal space and hermetically sealing the internal space of the base container 56. . The following literature is disclosed about the quartz crystal vibrating piece 51 as described above.
JP-A-11-289238 JP, 2000-40935, A In addition to the prior art document specified by the above-mentioned prior art document information, the applicant did not find the prior art document relevant to the present invention by the time of this application. .

However, as miniaturization of crystal resonators progresses, the crystal resonator element mounted inside the crystal resonator itself must be miniaturized, and as a result, the area where connection electrodes can be formed on the main surface of the crystal resonator element is very narrow. Thus, the shape of the extraction electrode is small.
For this reason, the area of the support part on the base container arranged within the area where the extraction electrode is formed is also reduced, the adhesive strength between the support part and the extraction electrode is weakened, and the worst conduction failure may occur. Further, since the contact area is small, the strength for holding the crystal vibrating piece is weak, and there is a high possibility that the crystal vibrating piece is dropped due to external force applied to the crystal vibrating piece. In order to avoid these problems, conventionally, when mounting the crystal vibrating piece on the support part, the holding adhesive strength is improved by covering the side surface of the crystal vibrating piece with the conductive adhesive member. There is a possibility that stress more than necessary is applied to the resonator element itself, and the vibration characteristics of the crystal resonator element are unstable.

  The present invention has been conceived in view of the above-described drawbacks. Therefore, the purpose of the present invention is to reduce the size of the quartz crystal resonator, thereby reducing the size of the quartz crystal vibrating piece itself. It is an object of the present invention to provide a support structure for a quartz crystal vibrating piece without deterioration of the adhesive strength of the piece.

The crystal vibrating piece support structure of the present invention includes a quartz crystal vibrating piece in which an excitation electrode and a lead electrode are formed on a rectangular quartz base plate, a substrate, a lid, and a side wall attached to the upper surface of the substrate. In the support portion structure mounted on the support portion provided on the upper surface of the substrate in the base container, the support portion does not protrude from the outer periphery of the main surface of the quartz crystal resonator element to be mounted on the side wall side. The upper surface of the substrate is disposed at a position shifted from the position corresponding to the position of the short side of the quartz crystal resonator element to be mounted toward the center of the upper surface of the substrate. Each of the divided support portions is divided into two parallel to the short side direction, and only the surface facing the quartz crystal vibrating piece and the inner wall surface of the long side of the adjacent side wall are provided on each of the divided support portions. A notch with an opening is formed in , The opening of the notch is the wall part is provided, there is a gap between the crystal vibrating piece to the wall portion, the quartz crystal resonator by a conductive adhesive member is injected into the notch This is a support structure in which the pieces are fixed and electrically connected.

As a specific example, a quartz crystal resonator element in which an excitation electrode and an extraction electrode are formed on a rectangular quartz base plate having a short side in the Z-axis direction and a long side in the X-axis direction, a substrate, a lid, In a support part structure mounted on a support part provided on the upper surface of the substrate in a base container comprising a side wall attached to the upper surface, the support part includes two short sides and two of the quartz crystal resonator element to be mounted. The center direction of the upper surface of the substrate from the position corresponding to the position of the short side of the quartz crystal resonator element to be mounted on the upper surface of the substrate so as not to protrude from the outer periphery of the main surface surrounded by the long side to the side wall side The support portion is divided into two parallel to the Z-axis direction short side of the crystal vibrating piece, and each of the divided support portions includes the crystal vibration. Pair with the opposite surface and the inner wall of the long side of the adjacent side wall. Surfaces only and notch is formed having an opening in, the aperture of the notch is the wall part is provided, there is a gap between the crystal vibrating piece to the wall portion, notch the cut The quartz crystal resonator element is fixed and conducted by being injected with a conductive adhesive member.

  According to the support structure of the quartz crystal resonator element of the present invention, by forming a notch on the support section side in the area where the extraction electrode of the crystal oscillator piece is formed, the extraction electrode and the support section formed on the area are formed. It is possible to increase the contact area.

  Further, according to the support structure of the quartz crystal resonator element according to the present invention, by forming a notch in the support part, even if there is a variation in the amount of application of the conductive adhesive member, the notch is formed in the support part. Excessive amount of the conductive adhesive member can be leaked, and the height position of the crystal vibrating piece can be made uniform with the height of the support portion.

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

  FIG. 1 is a cross-sectional view of a crystal oscillator when the support structure of the crystal resonator element 8 according to the embodiment of the present invention is applied to a crystal oscillator. FIG. 1A is a cross-sectional view of the entire crystal oscillator, and FIG. 1B is a cross-sectional view focusing on the support portion of the crystal vibrating piece 8. The crystal oscillator shown in FIG. 1 generally includes a base container 1, a frame 5, a crystal vibrating piece 8, a semiconductor component 37, and a resin 38. In the base container 1 shown in FIG. 1, external connection terminals 9 are provided at the four corners of the bottom surface of the frame portion 5. The external connection terminal 9 is electrically and mechanically connected and fixed to the frame portion 5 and functions as a connection terminal to a mounting board (not shown). A crystal vibrating piece 8 for forming an excitation electrode and an extraction electrode is mounted on a rectangular crystal base plate having a short side in the Z-axis direction and a long side in the X-axis direction. Further, the frame part 5 disposed at the outer position of the semiconductor component 37, and the semiconductor component 37 and the frame part 5 are covered with a resin 38. 2 and 3 are top views of the substrate 2 showing the structure of the support portion 6 of the quartz crystal resonator element 8 of the present invention. In FIG. 2, the support portion 6 is formed at a position corresponding to the lead electrode 12 formed on the crystal base plate 11, and FIG. 2 is a top view of the substrate 2 of FIG.

  The base container 1 includes, for example, a substrate 2 made of a ceramic material such as glass-ceramic and alumina ceramic, a side wall 3 made of a ceramic material similar to the substrate 2, and a lid 4 made of alloy, copal, phosphor bronze, or the like. The base container 1 is constructed by attaching the side wall 3 to the upper surface of the substrate 2 and mounting and fixing the lid 4 on the upper surface, and the conductive adhesive member is formed on the upper surface of the substrate 2 located inside the side wall 3. A crystal vibrating piece 8 is mounted via 13. The base container 1 contains a quartz vibrating piece 8 in a cavity 10 surrounded by the upper surface of the substrate 2, the inner surface of the side wall 3, and the lower surface of the lid body 4. Is. Here, a support portion 6 for mounting the crystal vibrating piece 8 is formed on the substrate 2, and a notch 7 is formed in the support portion 6.

  On the other hand, the quartz crystal vibrating piece 8 accommodated in the cavity 10 of the base container 1 is formed by attaching and forming a pair of excitation electrodes 14 on both main surfaces of the quartz base plate 11 cut along a predetermined crystal axis. When the fluctuating voltage is applied to the quartz crystal vibrating piece 8 via the pair of excitation electrodes 14, the thickness shear vibration is caused at a predetermined frequency.

  On the other hand, as shown in FIG. 1, a frame portion 5 is formed on the lower surface of the substrate 2 described above, and external connection terminals 9 are attached and formed at four corners of the frame portion 5. A flip chip type semiconductor component 37 formed in a rectangular shape is mounted on the lower surface of the substrate 2 positioned between the frame portions 5, and the semiconductor component 37 is connected to the substrate 2 via a conductive adhesive member 36. Has been. The space between the semiconductor component 37 and the substrate 2 is covered with a resin 38.

  Further, the semiconductor component 37 has, on its circuit formation surface, a temperature sensing element that detects the ambient temperature state, and temperature compensation data that compensates for the temperature characteristics of the crystal vibrating piece 8, and the crystal vibrating piece 8 is based on the temperature compensation data. Is provided with a temperature compensation circuit that corrects the vibration characteristics according to temperature changes, an oscillation circuit that is connected to the temperature compensation circuit and generates a predetermined oscillation output, and the oscillation output generated by the oscillation circuit is externally provided. After being output, it is used as a reference signal such as a clock signal. Here, the crystal vibrating piece 8 and the semiconductor component 37 are connected by a metallized wiring 15 provided in the inner layer of the substrate 2 shown in FIG.

  Here, as shown in FIGS. 1 to 3, the characteristic part of the present invention is that it has a support part structure in which a notch 7 is formed in the support part 6 on which the crystal vibrating piece 8 is mounted. As a result, the contact area between the crystal vibrating piece 8 and the support portion 6 increases, and the adhesion state between the crystal vibrating piece 8 and the conductive adhesive member 13 is deteriorated due to an impact when the crystal vibrating piece 8 is dropped. Therefore, it is possible to hold the crystal vibrating piece 8 on the support portion 6 in a state where the bonding state is stable.

  Further, in the support portion structure in the present invention, by forming the notch 7 in the support portion 6, even when the application amount of the conductive adhesive member 13 varies, the conductive adhesive member 13 at the notch 7 portion of the support portion 6. It is possible to leak out the excess amount, and the height position of the crystal vibrating piece 8 can be made uniform with the height of the support portion 6.

  Note that the present invention is not limited to the above-described embodiment, and various modifications and improvements can be made without departing from the spirit of the present invention.

  For example, in the above-described embodiment, the support portion 6 of the quartz crystal vibrating piece 8 is formed in a prismatic shape having a notch 7 formed in the inner periphery as shown in FIGS. It doesn't matter. Further, as shown in FIG. 4, a wall 16 serving as a barrier for adjusting the excess amount of the conductive adhesive member 13 depending on the viscosity of the conductive adhesive member 13 is formed in the notch 7 (opening thereof). It doesn't matter. Needless to say, this case is also included in the technical scope of the present invention.

  As shown in FIG. 5, the support portion 6 according to the present invention is arranged at a position inside the short side of the crystal vibrating piece 8 in the Z-axis direction, and further at a position inside the long side in the X-axis direction. This greatly acts to prevent the conductive adhesive member 13 from rising up to the short side of the crystal vibrating piece 8 in the Z-axis direction.

1 is a schematic cross-sectional view of a crystal oscillator according to an embodiment of the present invention. It is a schematic top view of the support part formed on the base container of the crystal oscillator of this invention. It is a schematic top view at the time of extending the support part formed on the base container of the crystal oscillator of this invention to the short side. It is a schematic top view at the time of forming a wall part in the notch of the support part formed on the base container of the crystal oscillator of this invention. It is a perspective view which shows the positional relationship of the support part of this invention. It is a schematic sectional drawing of the conventional crystal oscillator.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Base container 2 ... Board | substrate 3 ... Side wall 4 ... Lid body 5 ... Frame part 6 ... Support part 7 ... Notch 8 ... Crystal vibrating piece 9 ... External connection terminal 10 ... cavity 11 ... crystal base plate 12 ... leading electrode 13 ... conductive adhesive member 14 ... excitation electrode 15 ... metallized wiring 16 ... wall 20 ..Cavity 36 ... Conductive adhesive member 37 ... Semiconductor component 38 ... Resin

Claims (1)

A quartz crystal vibrating piece in which an excitation electrode and a lead electrode are formed on a rectangular quartz base plate is provided on the upper surface of the substrate in a base container including a substrate, a lid, and a side wall attached to the upper surface of the substrate. In the support part structure mounted on the support part,
From the place corresponding to the position of the short side of the quartz crystal resonator element to be mounted on the upper surface of the substrate so that the support portion does not protrude from the outer periphery of the main surface of the quartz crystal resonator element to be mounted to the side wall side. It is arranged at a position shifted toward the center direction of the upper surface of the substrate,
Further, the support portion is divided into two in parallel with the short side direction of the crystal vibrating piece,
Each of the divided support portions is formed with a notch having an opening only on the surface facing the quartz crystal vibrating piece and the surface facing the inner wall surface of the long side of the adjacent side wall,
The opening of the notch is provided with a wall portion, and there is a gap between the wall portion and the quartz crystal vibrating piece,
The support structure, wherein the crystal vibrating piece is fixed and electrically connected by injecting a conductive adhesive member into the notch.

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