JP2004096257A - Oscillator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an oscillator wherein a vibrator is easily be inspected even after assembling and the manufacture process is simplified. <P>SOLUTION: Integrally fitting both a base 2a and a frame 2b in a way of placing at least part of an outer circumferential part on an upper face of the base at the outside of the frame 2b extends part of the base 2a at the outside of the frame 2b and monitor pads 21a, 21a electrically connected to the vibrator are placed on an extension part 2a1. Thus, in the case of inspecting the electric characteristics, the inspection workability and the inspection efficiency are enhanced because no hindrance to a visual recognition work exists around the monitor pads 21a, 21a for the visual confirmation of a contact state between contact pins of an electric characteristics test unit and the monitor pads 21a, 21a. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an oscillator having a resonator such as a piezoelectric element or a crystal resonator and an oscillation control IC housed in a package.
[0002]
[Prior art]
As a conventional oscillator, for example, a crystal oscillator having a structure shown in FIGS. 6 to 8 is known. The crystal oscillator 51 shown in the figure has a structure in which a crystal oscillator 53 and an oscillation control IC 54 are mounted inside a ceramic package 52, and an opening of the ceramic package 52 is hermetically sealed with a metal lid 56. Have.
[0003]
The ceramic package 52 is configured by sequentially mounting frames 52b and 52c on the upper surface of a base 52a having a flat plate shape, and has a recess for mounting an oscillation control IC 54 and a quartz oscillator 53 mounted therein. The external terminal electrode 521 connected to the power supply voltage terminal, the ground terminal, and the output terminal of the oscillation circuit is formed on the lower surface of the step portion.
[0004]
The quartz oscillator 53 housed inside the ceramic package 52 is formed by attaching excitation electrodes 531 and 533 to both main surfaces of a strip-shaped quartz substrate. At one end, connection electrodes 532 and 534 are provided, which extend from one end of each of the excitation electrodes 531 and 533.
[0005]
The connection electrodes 532 and 534 of the crystal unit 53 are electrically connected to the connection pads 58 and 58 for the units provided on the upper surface of the frame 52b through a conductive adhesive 57, and the oscillation control is performed. The IC for bonding 54 is bonded to a connecting pad for IC on the upper surface of the base via a thin metal wire 59.
[0006]
[Problems to be solved by the invention]
By the way, in the above-mentioned conventional oscillator, usually, after the assembly of the oscillator is completed, the electrical characteristics are inspected by measuring the impedance characteristics of the crystal unit 53 with an electric characteristics tester. Therefore, an end face through hole is provided on the side surface of the ceramic package 52, and a monitoring pad 522 electrically connected to the connection electrodes 532 and 534 of the crystal unit 53 is attached and formed on the inner surface.
[0007]
However, since the inner surface of the through hole on the end surface on which the monitor pad 522 is attached has a concave curved surface, the contact pin 52N of the electric characteristic tester is connected to the end surface through hole in the inspection of the electric characteristics described above. When making contact with the monitor pad 522 in the hole (see FIG. 9), it is difficult to visually check whether the tip of the contact pin 52N is in contact with the monitor pad 522, and the workability and efficiency of the inspection are reduced. It was significantly lower.
[0008]
Further, according to the conventional oscillator described above, since the monitoring pad 522 is provided on the end face of the frame 52b, to manufacture such an oscillator, the connection pads 58, 58, etc. are provided on the upper surface of the frame 52b. In addition to the process of forming a conductor pattern for the process, a process of forming a conductor pattern for the monitor pad 522 is required also on the end face of the frame 52b, which also has the disadvantage that the manufacturing process of the oscillator is complicated. Had.
[0009]
The present invention has been made in view of the above-described drawbacks, and an object of the present invention is to provide an oscillator that can easily inspect a vibrator even after assembling and that can simplify a manufacturing process. Is to do.
[0010]
[Means for Solving the Problems]
The oscillator according to the present invention, the base and the frame, at least a portion of the outer peripheral portion of the upper surface of the base is positioned outside the frame, and the two are integrally attached to each other. A pair of conductor layers having connection pads are formed, and a vibrator having a pair of connection electrodes connected to the connection pads and an oscillation control IC are mounted on a base located in an inner region of the frame. And an oscillator having a lid placed and fixed on the frame, wherein one end of the pair of conductor layers is extended on an upper surface of a base located in an outer region of the frame, and The extension portion is a monitor pad for measuring electrical characteristics of the vibrator.
[0011]
According to the oscillator of the present invention, the base and the frame are attached together such that the outer peripheral portion of the upper surface of the base is at least partially positioned outside the frame, and a part of the base is attached. Since the monitor pad is extended outside the frame body and the monitor pad electrically connected to the vibrator is arranged on the extended portion, the contact of the electrical property tester is required when inspecting the electrical property. When observing the contact state between the pin and the monitor pad, there is no obstacle around the monitor pad that hinders the visual inspection operation, and the workability and the inspection efficiency of the inspection can be improved.
[0012]
According to the oscillator of the present invention, since the monitor pad is provided on the upper surface of the base, the monitor pad can be formed at the same time when a conductor pattern such as a connection pad is formed on the upper surface of the base. Thus, the manufacturing process of the oscillator can be simplified.
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the oscillator of the present invention will be described in detail with reference to the drawings.
1 is a perspective view of an oscillator according to an embodiment of the present invention, FIG. 2 is a top view showing a state where a lid is removed from the oscillator of FIG. 1, and FIG. 3 is a cross-sectional view taken along the line AA of FIG. In the oscillator 1 shown in FIG. 1, a quartz oscillator 3 as an oscillator and an oscillation control IC 4 are mounted inside a ceramic package 2, and a lid 6 is placed on the ceramic package 2 via a seal ring 5. It is mounted and fixed, and has a structure in which the housing area of the crystal unit 3 and the oscillation control IC 4 is hermetically sealed with the lid 6.
[0014]
The ceramic package 2 includes a ceramic flat base 2a formed in a substantially rectangular shape and a ceramic frame 2b attached to the upper surface thereof. Is attached at least partially outside the frame 2b, so that a part of the base 2a extends outside the frame 2b.
[0015]
On the upper surface of such a ceramic package 2, a cavity 20 for accommodating the crystal oscillator 3 and the oscillation control IC 4 is formed in a region surrounded by the inner surface of the frame 2b and the upper surface of the base 2a. On the upper surface of the base 2a, a pair of conductor layers having oscillator connection pads 8, 8 connected to the connection electrodes of the crystal oscillator 3 and an oscillation control IC 4 are mounted in the inner region of the frame 2b. The die attach portion 41, other conductor patterns, and the like are formed in a predetermined pattern, and a power supply voltage terminal, a clock output terminal, and a ground terminal electrically connected to the lower surface of the base 2a via the via-hole conductors 10 inside the base. External terminals 21 are formed. When the crystal oscillator 1 is mounted on an external circuit board such as a motherboard (not shown), these external terminals 21 are electrically connected to connection pads on the external circuit board via a conductive adhesive such as solder. The terminal functions as a terminal for connection to the terminal.
[0016]
Further, on the upper surface of the base 2a constituting the ceramic package 2, a pair of the above-described conductors is formed in an outer region of the frame 2b, that is, an extension 2a1 of the base 2a provided so as to protrude outside the frame 2b. One end side of the layer is led out, and monitor pads 21a, 21a for inspection are formed in the led-out portion.
[0017]
The monitor pads 21a, 21a are each formed on the upper surface of the substantially flat base 2a so as to form a substantially rectangular shape. After the assembly of the oscillator is completed, the impedance characteristics of the crystal unit 3 are subjected to an electrical characteristic test. The contact pin 2N of the electrical property tester comes into contact when measuring with a tester.
[0018]
A pair of conductor layers having the monitor pads 21a, 21a and the vibrator connection pads 8, 8 is formed of a conductive paste containing a metal powder of molybdenum, tungsten, or the like by a conventionally well-known screen printing or the like. It is formed by printing and applying a predetermined pattern on the upper surface and baking it at a high temperature, and by applying Ni plating, Au plating, or the like on a part of the upper surface, the monitor pads 21a, 21a and the connection pads for the vibrator are formed. 8, 8, etc. are formed. In this case, the monitor pads 21a, 21a are located on the upper surface of the base 2a and can be formed simultaneously with the formation of the conductor patterns such as the vibrator connection pads 8, 8, so that the manufacturing process of the oscillator is reduced. Simplified.
[0019]
In addition, as an electrical characteristic tester used for the impedance characteristics of the crystal unit 3, equivalent parameters such as inductance and capacitance can be measured in addition to the resonance frequency fr and CI (crystal impedance) of the crystal unit 3. A network analyzer or the like is used, and the contact pins 2N are composed of a highly conductive pin having a gold-plated surface of an alloy such as copper and silver, and a resilient socket having a spring property for suppressing a shock at the time of contact. The measurement is performed by bringing this into contact with the monitoring pads 21a, 21a.
[0020]
As described above, the base 2a and the frame 2b are integrally attached to each other such that the outer peripheral portion of the upper surface of the base is located at least partially outside the frame 2b. Is extended to the outside of the frame 2b, and the monitor pads 21a, 21a electrically connected to the crystal unit 3 are arranged on the extended portion. In observing the contact state between the contact pin 2N of the electrical property tester and the monitoring pads 21a, 21a from above, there is no obstacle around the monitoring pads 21a, 21a that hinders the visual inspection operation. The property becomes good. As a result, workability and inspection efficiency of the inspection in the crystal oscillator are dramatically improved.
[0021]
In addition, as the quartz oscillator 3, for example, a pair of excitation is performed on both main surfaces of a rectangular quartz substrate 30 cut (AT cut) according to a predetermined crystal azimuth angle by employing a conventionally known thin film forming technique or the like. Electrodes 31 and 33 are attached, and connection electrodes 32 and 34 are formed at one end of excitation electrodes 31 and 33. Such a crystal resonator 3 is formed by connecting connection electrodes 32 and 34 with a conductive adhesive. It is mounted and accommodated in the cavity 20 by being bonded to the corresponding vibrator connection pads 8 on the upper surface of the base via the. As the conductive adhesive 7, for example, a material obtained by adding and mixing a predetermined amount of a conductive filler such as an Ag powder in a resin material such as a silicon-based resin, an epoxy-based resin, or a polyimide-based resin is used. When the child 3 is bonded, it is applied to a bonding site by a dispenser or the like.
[0022]
The oscillation control IC 4 is formed by forming an oscillation inverter, a load capacitance component, a feedback resistor and the like by PN doping on one main surface of a silicon chip, and is provided at a predetermined position on the upper surface of the base located in the inner region of the frame 2b. The cavity is formed by mounting the terminal electrodes provided on the main surface of the crystal oscillator 3 together with the quartz oscillator 3 to the corresponding IC connection pads on the upper surface of the substrate by a conventionally known wire bonding method or the like. 20 to be mounted and accommodated. By mounting such an oscillation control IC 4 in the ceramic package 2, the connection electrodes 32 and 34 of the crystal unit 3 and the oscillation control IC 4 are electrically connected via a predetermined conductor pattern, and the oscillation circuit Is configured.
[0023]
On the other hand, the seal ring 5 and the lid 6 attached on the ceramic package 2 are made of a metal such as an Fe-Ni alloy (42 alloy) or Fe-Ni-Co (Kovar), and the seal ring 5 is not shown. The lid 6 is fixed to the upper surface of the frame 2b by brazing via a sealing conductor film, and the lid 6 is joined to the upper surface of the seal ring 5 by a conventionally known resistance welding (seam welding) or the like. In the present embodiment, the above-described resistance welding is performed in a nitrogen gas atmosphere or in an inert gas atmosphere so that the characteristics of the quartz oscillator 3 and the like do not change due to corrosion or the like caused by contact with moisture or oxygen contained in the atmosphere. This is performed in a gas atmosphere, whereby the inside of the cavity 20 in which the crystal resonator 3 is accommodated is filled with nitrogen gas, inert gas, or the like. Further, a Ni plating layer or the like is adhered and formed on the surface side of the lid 6, so that the brazing material melted by welding goes around to the surface side of the lid 6 and the brazing material contributing to the bonding is reduced. Not to be. Further, if an Ag brazing layer or the like is formed in advance on the joint surface side of the lid 6, the welding operation can be performed more reliably.
[0024]
Further, in the present embodiment, since the monitor pads 21a, 21a are formed on the extending portion 2a1 of the ceramic package 2, the ceramic package 1 is composed of only two layers of the base 2a and the frame 2b. It is also possible to provide a crystal oscillator having a small size and a small thickness.
[0025]
Note that the present invention is not limited to the above-described embodiment, and various changes and improvements can be made without departing from the gist of the present invention.
[0026]
For example, in the above-described embodiment, the extension 2a1 of the base 2a is provided only at one end of the ceramic package 2, and two monitor pads 21a, 21a are provided in this portion. As shown in FIG. 4, the ends of the base 2a are extended in two directions to provide extensions 2a2, 2a3, and one monitor pad 21b, 21c is provided on each extension 2a2, 2a3. You may do it.
[0027]
Further, in the above-described embodiment, as shown in FIG. 5, a part of the frame may be extended to both sides of the monitor pads 21d, 21d to surround the monitor pads 21d, 21d with the frame. Further, a part of the frame may be extended and arranged between the monitor pads 21d, 21d, and the two monitor pads 21d, 21d may be surrounded by the frame one by one.
[0028]
Further, in the above-described embodiment, the crystal resonator 3 and the oscillation control IC 4 are accommodated in the same cavity 20. Instead, the crystal resonator 3 and the oscillation control IC 4 are separated from each other. They may be accommodated in the cavities, respectively. For example, in the above-described embodiment, a frame is separately attached to the lower surface of the base 2a to form a cavity also on the lower surface side of the base 2a. The oscillation control IC 4 may be accommodated in the cavity.
[0029]
Further, in the above-described embodiment, the lid 6 is welded to the upper surface of the seal ring 5 attached to the ceramic package 2 to close the cavity 20 of the ceramic package 2. Alternatively, a metallized layer may be formed on the upper surface of the ceramic package, and the lid may be directly welded to the metallized layer.
[0030]
Furthermore, in the above-described embodiment, the crystal oscillator using the crystal resonator 3 as the resonator has been described as an example. However, the present invention can be applied to an oscillator using a resonator other than the crystal resonator. Needless to say, passive components such as capacitors may be mounted in the cavity 20 and connected to the oscillation circuit in order to stabilize the operation of the output signal and the oscillation control IC.
[0031]
【The invention's effect】
According to the oscillator of the present invention, the base and the frame are attached together such that the outer peripheral portion of the upper surface of the base is at least partially positioned outside the frame, and a part of the base is attached. Since the monitor pad is extended outside the frame body and the monitor pad electrically connected to the vibrator is arranged on the extended portion, the contact of the electrical property tester is required when inspecting the electrical property. When observing the contact state between the pin and the monitor pad, there is no obstacle around the monitor pad that hinders the visual inspection operation, and the workability and the inspection efficiency of the inspection can be improved.
[0032]
According to the oscillator of the present invention, since the monitor pad is provided on the upper surface of the base, the monitor pad can be formed at the same time when a conductor pattern such as a connection pad is formed on the upper surface of the base. As a result, the manufacturing process of the oscillator can be simplified.
[Brief description of the drawings]
FIG. 1 is a perspective view of an oscillator according to an embodiment of the present invention.
FIG. 2 is a top view showing a state where a lid is removed from the oscillator of FIG. 1;
FIG. 3 is a sectional view taken along the line AA of FIG. 2;
FIG. 4 is a perspective view of an oscillator according to another embodiment of the present invention.
FIG. 5 is a perspective view of an oscillator according to another embodiment of the present invention.
FIG. 6 is a sectional view of a conventional oscillator.
FIG. 7 is a perspective view of a conventional oscillator.
FIG. 8 is a top view showing a state where a lid of a conventional oscillator is removed.
FIG. 9 is a perspective view illustrating a conventional oscillator inspection method.
[Explanation of symbols]
1 ・ ・ ・ Oscillator (crystal oscillator)
2 Ceramic package 2a Base 2b Lids 2a1, 2a2, 2a3, 2a4 Projections 21a, 21b, 21c, 21d Monitor pad 3 Vibrator (crystal Vibrator)
4: Oscillation control IC
5 Seal ring 6 Lid

Claims (1)

The base and the frame, at least a part of the outer peripheral portion of the upper surface of the base is positioned outside the frame, and the two are integrally attached to each other, and a pair of connection pads having a connection pad in an inner region of the frame. Forming a conductor layer, mounting a vibrator having a pair of connection electrodes connected to the connection pads on a base located in an inner region of the frame, and an oscillation control IC; An oscillator having a lid placed and fixed on the base, wherein one end of the pair of conductor layers extends on the upper surface of a base located in an outer region of the frame, and An oscillator comprising a monitor pad for measuring the electrical characteristics of a child.

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