JP3451018B2 - Crystal oscillator - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface mountable crystal oscillator used in, for example, mobile communication equipment.

[0002]

2. Description of the Related Art Conventionally, a crystal oscillator is composed of an IC chip in which a crystal oscillator and an oscillation circuit are integrated in whole or in part, and various electronic parts which cannot be integrated in the IC chip as necessary. It had been.

In such a crystal oscillator, the structure shown in FIGS. 7 and 8 has already been proposed as a structure for surface mounting on a printed wiring board through reflow soldering or the like.

The crystal oscillator 70 includes a crystal oscillator 75, an IC
A ceramic container 71 that houses a chip 76 and the like therein;
It was composed of a metal lid 72 that seals the opening of the ceramic container 71 by seam welding.

The ceramic container 71 includes, for example, a first ceramic layer 71a and a second ceramic layer 71 from the lid side.
b, the third ceramic layer 71c, the fourth ceramic layer 7
It is composed of 1d.

The first ceramic layer 71a has a ring shape, and a cavity portion 73 that mainly houses the crystal unit 75 is formed.
And a sealing conductor film for fixing the seal ring 77 is formed around the upper surface opening.

The second ceramic layer 71b has a ring shape, and the cavity portion 7 mainly houses the IC chip 76 and the like.
4, a crystal oscillator 75 is arranged on the upper surface thereof, and crystal oscillator pads 78, 78 to which the vibration electrodes of the crystal oscillator 75 are connected are formed.

The third ceramic layer 71c has a substantially flat plate shape, forms the bottom surface of the cavity portion 74, and has an IC structure.
IC pads 79 are formed on which the chips 76 are arranged and which are electrically connected to the IC chips 76.

The fourth ceramic layer 71d has a substantially flat plate shape having through holes and the like, and mainly serves as legs of the ceramic container. On the lower surface of the fourth ceramic layer 71d, a conductor film having a substantially ground potential is deposited.

The power supply voltage terminal, the ground terminal, the oscillation output terminal and the like of the crystal oscillator 70 are distributed to the respective terminal electrodes formed at the four corners of the container.

On the upper surface side of the third ceramic layer 71c, wiring patterns constituting a predetermined oscillation circuit, IC pads 79, etc. are formed, and the fourth ceramic layer 7 is formed.
Crystal oscillator frequency monitor electrodes 80, 80 are formed on the lower surface of the third ceramic layer 71c exposed from the through hole 1d, and wiring patterns forming a predetermined oscillation circuit are formed on the upper surface side.

Further, the crystal oscillator pads 78, 78 formed on the second ceramic layer 71b are oscillated by the crystal oscillation on the lower surface of the third ceramic layer 71c via a predetermined oscillation circuit on the upper surface of the third ceramic layer 71c. Child frequency monitor electrode 80,
80.

Further, in the crystal unit 75, vibrating electrodes formed by vapor deposition of Ag or the like are formed on both main surfaces of the crystal substrate, and extension electrodes extending from the respective vibrating electrodes are formed at one end. There is.

Further, the IC chip 76 is made of silicon or the like, and an input / output electrode made of aluminum is formed on one main surface thereof.

The metal lid 72 is made of, for example, the same material as the seal ring 77, such as Kovar or phosphor bronze, and is firmly adhered to the seal ring 77 by seam welding or the like. Incidentally, the seam ring 77 is a sealing conductor film and a brazing material made of tungsten, a molybdenum underlayer, a Ni plating layer, an Au plating layer, etc., which are deposited and formed around the opening of the first ceramic layer 71a of the ceramic container 71. It is firmly fixed via.

The crystal oscillator having such a structure is manufactured by the following steps.

First, a ceramic container 71 to which a seal ring 77 is fixed, a crystal oscillator 75, an IC chip 76, etc. are prepared.

Next, the IC chip 76 is mounted in the lower cavity portion 74 of the ceramic container 71. Specifically, the IC chip 76 is bonded and connected between the input / output pad of the IC chip 76 and the IC pad 79 ... Joined to the bottom surface of the cavity 74 via Au wires. In addition, A on the input / output pad of the IC chip 76
u bumps are formed and bonded to the IC pads 79 ... by ultrasonic fusion or conductive paste.

Next, a crystal oscillator 75 is mounted in the upper cavity portion 73 of the ceramic container 71. Specifically, the crystal resonator pads 78, 78 formed on the upper surface of the second ceramic layer 71b are arranged so that the extraction electrodes of the crystal resonator 75 are aligned with each other, and electrically connected via an Ag-based conductive resin paste. , Mechanically join.

Next, a probe of a frequency measuring device is applied to the crystal oscillator frequency monitor electrodes 80, 80 exposed from the bottom surface side of the ceramic container 71 to measure the oscillation frequency of the crystal oscillator 75 mounted in the ceramic container 71. ,at the same time,
In order to correct the frequency deviation, an adherend for frequency adjustment is formed by vapor deposition on the surface of the vibrating electrode of the crystal unit 75, if necessary. Thereby, the oscillation frequency of the crystal unit 75 mounted in the ceramic container 71 can be set to the design value.

Next, in an oscillator using a crystal oscillator, an indispensable frequency stabilizing process (annealing process) is performed. Specifically, the oscillator is left in an atmosphere of about 150 to 250 ° C. to stabilize the deposited film deposited on the vibrating electrode of the crystal unit 75.

Next, the metal lid 72 seals both the cavity portions 73 and 74. Specifically, the metal lid 72 is placed on the seal ring 77 on the upper surface of the ceramic container 71, and a welding current is applied between the metal lid 72 and the seal ring 77 to weld them together.

[0023]

In the above-mentioned structure, the crystal resonator 7 is disposed in the substantially same cavity portions 73, 73.
5, the IC chip 76 is arranged. Therefore, when defective oscillation occurs, the entire oscillator including the crystal oscillator 75 and the IC chip 76 must be discarded.

In connection with the IC chip, an input / output electrode of Al and an Au wire or Au bump are joined to one main surface of the IC chip 76. Then, as described above, since the resonator mounting step is performed later, a thermal history of several hours is required at 200 ° C. or higher in the annealing step for stabilizing the vapor deposition film and the like. Due to this high-temperature heat treatment, a Kagendahl void occurs due to the difference in the diffusion speed of Al and Au at the connection surface of the Au wires (bumps) joined to the Al input / output electrodes of the IC chip, and the connection strength is significantly deteriorated. Was sometimes invited.

Further, in order to measure the oscillation frequency of the mounted crystal unit 75, the frequency is externally monitored.
Since the crystal unit frequency monitor electrodes 80, 80 exposed from the bottom surface side of the ceramic container 71 are formed,
When a crystal oscillator is surface-mounted on a printed wiring board,
Stray capacitance is generated between the crystal unit frequency monitor electrodes 80 and 80 and a predetermined wiring pattern on the printed wiring board. As a result, the very stable frequency characteristics that have undergone the frequency adjustment process and the annealing process will vary due to this stray capacitance.

The present invention has been devised in view of the above-mentioned problems, and its object is to be economically very inexpensive, and to obtain oscillation characteristics even when surface-mounted on a printed wiring board. A crystal oscillator that does not fluctuate is provided.

[0027]

The crystal oscillator of the present invention comprises:
A crystal resonator is arranged on the other main surface of a ceramic container having a cavity portion in which an IC chip is arranged on one main surface, and the crystal resonator is hermetically sealed by a ceiling and a metal lid. A crystal oscillator, wherein the crystal oscillator is connected to the crystal oscillator within a gap between the bottom surface of the cavity located in the arrangement area of the IC chip and the IC chip, and is connected to the crystal oscillator. The monitor electrode with which the measuring terminal of the frequency measuring device is brought into contact when the oscillation characteristic is inspected is formed to have a larger area than the mounting electrode pad on the bottom surface of the cavity connected to the input / output electrodes of the IC chip. It is characterized by. Further, the crystal oscillator of the present invention is characterized in that, when the ceramic container is viewed from the one main surface side, the monitor electrode is hidden by the IC chip. Further, the crystal oscillator according to the present invention is characterized in that the IC chip is mounted on the bottom surface of the cavity portion via a bump after the oscillation characteristic of the crystal resonator is inspected. Furthermore, the crystal oscillator according to the present invention is characterized in that the silicon chip of the IC chip is at ground potential.

[0028]

In the present invention, the monitor electrode for measuring the oscillation characteristic of the crystal unit during the manufacturing process is formed on the bottom surface of the cavity portion in the region where the IC chip is arranged. Therefore, when the crystal oscillator is mounted on a printed wiring board, an IC chip whose chip is substantially at the ground potential exists between the wiring pattern on the printed board and the monitor electrode. Does not generate stray capacitance. As a result, the frequency stabilization process (thermal annealing process)
Since the elements that can change the oscillation characteristics of the crystal unit are eliminated after performing the above step, the oscillation characteristics do not change even when surface-mounted on the printed wiring board.

Further, the water oscillator and the IC chip are separately arranged in the spaces (cavity portion, accommodating region) of different main surfaces of the ceramic container. Therefore, if the oscillation characteristics of the crystal unit are monitored and the oscillation failure occurs, it is not necessary to mount the IC chip.
It is very economically economical.

Further, since the IC chip can be placed in the cavity of the ceramic container after the frequency adjustment and the annealing process of the crystal unit are carried out, the cartage at the bonding interface between the Al electrode of the IC chip and the Au bump. The Darvoid phenomenon does not occur. Further, unnecessary heat history is not applied to the IC chip. This also provides a crystal oscillator with stable characteristics.

[0031]

BEST MODE FOR CARRYING OUT THE INVENTION A crystal oscillator of the present invention will be described below with reference to the drawings.

FIG. 1 is an external perspective view of a crystal oscillator according to the present invention, FIG. 2 is a sectional view taken along line XX of FIG. 1, and FIG. 3 is a top view with a metal lid omitted. FIG. 4 is a bottom view. 5 (a) is a wiring pattern diagram on the upper surface side of the second ceramic layer, FIG. 5 (b) is a wiring pattern diagram on the lower surface side of the second ceramic layer, and FIG. 6 is a crystal oscillator of the present invention. FIG. 6 is a process drawing for explaining the method.

The crystal oscillator 10 of the present invention includes, for example, a ceramic container 1 formed by laminating four ceramic layers, a metal lid body 2, a crystal resonator 3, an IC chip 4, an electronic component element 5, an IC coating resin 6, It is composed of a seal ring 7.

The ceramic container 1 is composed of, for example, four ceramic layers 1a to 1d of alumina. For example, the first ceramic layer has a substantially planar shape from the upper surface side, and a sealing conductor film for fixing the seal ring 7 is adhered and formed on the outer periphery of the surface. Also, the first
A mounting member 11 for the crystal unit 3 is formed in the accommodation area Y of the ceramic layer 1a that is fixed to the seal ring 7. The mounting member 11 is a base such as ceramic,
A crystal oscillator electrode pad 12 is adhered and formed on the surface thereof. When the end of the crystal unit 3 is arranged, the mounting member 11 is provided between the upper surface of the crystal unit 3 and the metal lid 2 and between the lower surface of the crystal unit 3 and the surface of the first ceramic layer 1a. A predetermined space is formed between them. In the figure, two mounting members 11 (11a, 11b) are formed.

The second ceramic layer 1b has a substantially flat shape, and the second ceramic layer 1b is formed between the first ceramic layer 1a and the first ceramic layer 1a as shown in FIG.
The predetermined wiring pattern as shown in FIG. On the lower surface side of the second ceramic layer 1b, the predetermined wiring pattern shown in FIG. 5B, the mounting electrode pad 13 of the IC chip 4, the mounting electrode pad 14 of the electronic component element 5 ,.
Then, a monitor electrode 15 for measuring the frequency of the crystal oscillator, which has a larger area than the mounting electrode pad 13 of the IC chip 4
a and 15b are adhered and formed.

The third ceramic layer 1c has a substantially ring shape. Further, the fourth ceramic layer 1d has a substantially ring shape whose opening shape is larger than the opening shape of the third ceramic layer 1c. Further, a conductor film 16 having a ground potential is formed on the lower surface of the fourth ceramic layer 1d.

The mounting electrode pad 1 of the electronic component element 5 is formed on the first ceramic layer 1a and the second ceramic layer 1b.
Monitor electrode 1 from 4 ... via a predetermined wiring pattern
Via-hole conductors 17a and 18a are formed to electrically connect 5a and 15b.

Such a sealing conductor film, a predetermined wiring pattern, mounting electrode pads 13 and 14, monitor electrodes 15a and 1
5b, the conductor film 16 at the ground potential is made of a metallized conductor film of molybdenum, tungsten, or the like.
On the conductor film exposed from the surface of the ceramic layer 1a, the lower surface of the second ceramic layer 1B, and the lower surface of the fourth ceramic layer 1d, a Ni plating layer and a Au flash plating layer are formed by deposition. The via-hole conductors 17a, 17b,
18a and 18b are substantially filled with a metal material such as molybdenum or tungsten.

Further, at the four corners of the ceramic container 1, there are formed recesses extending in the thickness direction and the terminal electrodes 10a to 1 made of the above-described conductor film and plating layer formed on the inner walls of the recesses.
0d is formed. For example, this terminal electrode is a terminal for connecting to a bias voltage and a ground voltage of a predetermined oscillation circuit and for outputting an oscillation output signal.

Such a ceramic container 1 is, for example,
A through hole to be a via hole conductor or a ring-shaped through hole is formed in the green sheet to be the first to fourth ceramic layers, and a conductive paste is filled in the through hole to be the via hole conductor of each green sheet. Accordingly, a conductive film to be each wiring pattern or the like is printed on one main surface of the green sheet by using a conductive paste, such green sheets are laminated, integrally fired, and plated.

Sealing conductor film 1 on the surface of the ceramic container 1.
A seal ring 7 made of, for example, Kovar or phosphor bronze is fixed on 0x by brazing or the like.

A housing area Y surrounded by the seal ring 7
The crystal unit 2 is bonded onto the mounting members 11a and 11b.

The crystal resonator 2 is formed by a rectangular crystal substrate 20 cut into predetermined cuts and vapor deposition of Ag or the like on both main surfaces of the crystal substrate 20 in order to enable oscillation in a predetermined vibration mode. The vibrating electrodes 21 and 22 and the extraction electrodes 21a and 22a extending from the pair of vibrating electrodes 21 and 22 to one end of the quartz substrate 20. The crystal unit 2 is mounted on the ceramic container 1, and then a conductor for frequency adjustment is vapor-deposited on the vibrating electrode as needed.

The above-mentioned crystal unit 2 is a ceramic container 1.
Are placed and joined to the placing members 11a and 11b. Specifically, the crystal unit electrode pads 12a and 12b of the mounting members 11a and 11b and the extraction electrode 21 of the crystal unit 2 are arranged.
a and 22a are aligned with each other, and these parts are joined by conductive resin adhesive members 23a and 23b containing a powder such as Ag.

The metal lid 3 is made of the same material as that of the seal ring 7, for example, Kovar or phosphor bronze, and its outer peripheral portion is integrally formed with the seal ring 7 by seam welding. As a result, the crystal unit 2 is hermetically sealed in the space X between the surface of the ceramic container 1, the seal ring 7 and the metal lid 3.

The IC chip 4 is formed by integrating an inverter and the like which form an oscillation circuit. In particular,
The silicon member 41 is formed by injecting a predetermined doping material to form a predetermined circuit. Further, an input / output electrode 42 made of aluminum for bump bonding is formed on one main surface of the silicon member 41.

Such an IC chip 4 is arranged in a cavity portion 19 (formed by the third and fourth ceramic layers 1c and 1d) formed on the lower surface side of the ceramic container 1, For example, it is bonded to the mounting electrode pad 13 formed on the lower surface side of the second ceramic layer 1b corresponding to the bottom surface of the cavity portion 19. In addition, joining is IC
Au bumps 43 are formed on the input / output electrodes 42 of the chip 4, and the Au bumps 43 and the mounting electrode pads 13 are fused together.

The electronic component element 5 is, for example, a resistor or a large-capacity capacitor that is difficult to integrate in an oscillation circuit, and is a bottom surface of the cavity portion 19 (a lower surface of the second ceramic layer 1b).
It is electrically connected to the mounting electrode pad 14 formed in 1) via solder or the like, and is mechanically joined. If a resistor, a large-capacity capacitor, or the like, which is difficult to integrate, is mounted on an external printed wiring board, the crystal oscillator can be omitted.

The IC coating resin 6 is formed by filling and curing the cavity portion 19 in which the IC chip 4 and the electronic component element 5 are arranged so that at least the IC chip 4 is completely coated. Examples of the IC coating resin 6 include resins such as epoxy resin and silicon resin. The IC coating resin 6 is filled in the cavity portion 19,
In order to arrange the ceramic container 1 on the printed wiring board, it is important not to project it from the cavity portion 19.

In the crystal oscillator 10 having such a structure, the monitor electrode 1 for measuring the frequency characteristic of the crystal resonator 2
Reference numerals 5a and 15b are bottom surfaces of the cavity portion 19 in which the IC chip 4 is mounted, and are formed below the IC chip 4.
That is, in the plan view of the back surface side of the ceramic container 1 of FIG. 4, the monitor electrodes 15a and 15b shown by the alternate long and short dash line are arranged in the mounting area of the IC chip 4 shown by the dotted line portion. There is.

Next, a method of manufacturing the above-mentioned crystal oscillator will be described with reference to FIG.
It will be described based on.

First, as shown in FIG. 6A, a mounting container 11 and various electrodes (conductors, electrode pads, via-hole conductors) 12-18 are formed, and a ceramic container 1 to which a seal ring 7 is attached is formed. The crystal oscillator 2, the metal lid 3, for example, the IC chip 4 to which the Au bumps 43 are adhered and the electronic component element 5 are prepared.

Next, as shown in FIG. 6B, the crystal unit 2 is mounted. Specifically, a conductive paste is applied to the mounting members 11, 11 in the region surrounded by the seal ring 7, and then one end of the crystal resonator 2, that is, the extraction electrode 22a of the crystal resonator 2, 22b to the mounting members 11, 1
The crystal oscillator electrode pads 12a and 12b of the crystal oscillator 1 are aligned with each other, and then the extraction electrode 2 of the crystal oscillator 2 is aligned.
A conductive paste is applied on the surfaces 2a and 22b and mounted by a predetermined curing method (heat curing or ultraviolet curing).

As a result, the vibrating electrode 2 of the crystal unit 2
1 and 22 are led out to the monitor electrodes 15a and 15b exposed on the bottom surface of the cavity portion 19 of the ceramic container 1 through the crystal oscillator electrode pads 12a and 12b and the via hole conductors 17a, 17b, 18a and 18b. Become.

Next, as shown in FIG. 6C, the frequency of the crystal oscillator 2 is adjusted. Specifically, the measuring terminals (probes) of the frequency measuring device are brought into contact with the monitor electrodes 15a and 15b exposed on the bottom surface of the cavity portion 19 of the ceramic container 1 to cause the crystal oscillator 2 to oscillate in a predetermined manner to change the frequency. taking measurement. Based on the result, metal such as silver is vapor-deposited on the vibrating electrode 21 of the crystal resonator 2 from the upper surface side of the ceramic container 1, and the vibrating electrode 21 is substantially weighted while the oscillation frequency is set to a predetermined value. To Next, FIG.
As shown in (d), the frequency of the crystal unit 2 hermetically sealed with the metal lid 3 is stabilized. Specifically, the crystal resonator 2 is sealed and the entire ceramic container 1 is
Heat treatment is performed at ˜250 ° C. This heat treatment is generally called heat aging. Due to this heat aging, the vibrating electrode 21
The deposition material for frequency adjustment deposited on the top is stabilized, and the impurities such as the solvent contained in the conductive paste are volatilized.

Next, as shown in FIG. 6 (e), the metal lid 3 is sealed. Specifically, the metal lid 3 is placed on the seal ring 7 in a predetermined atmosphere in the region X, and the periphery of the metal lid 3 is covered with a roller electrode (not shown) for seam welding, and the capacitance current is increased. Weld them by moving them while applying.

Next, as shown in FIG. 6F, the electronic component element 5 is mounted. Specifically, A is applied to the electrode pad 14.
A conductive resin paste containing g powder or the like is applied, the electronic component element 5 is placed, and curing is performed. If it is not necessary to use the electronic component element 5, this step can be omitted.

Next, as shown in FIG. 6G, the IC chip 4 is mounted. Specifically, the IC chip 4 in which the Au bumps 43 are formed on the aluminum input / output electrodes 42
Are positioned and mounted so that the mounting electrode pads 13 arranged on the bottom surface of the cavity portion 19 of the ceramic container 1 and the Au bumps 43 come into contact with each other, and then ultrasonic waves or the like are applied to the IC chip 4 to melt them. To wear.

As a result, by mounting the IC chip 4,
The monitor electrodes 15a and 15b are hidden by the IC chip 4 when viewed from the back surface side of the ceramic container 1.
When connecting using the Au bumps 43, a gap corresponding to the height of the bumps is formed between the cavity portion 19 and the IC chip 4, so that the monitor electrode 1
5a, 15b and the IC chip 4 are not short-circuited.

Next, as shown in FIG. 6H, the IC chip 4 is covered with resin or the like. Specifically, the IC coating resin 6 disposed in the cavity portion 19 and, if necessary, the electronic component element 5 is filled with a resin paste such as a thermosetting or ultraviolet curable epoxy resin or silicon resin, Curing is performed by a predetermined curing method.

In the crystal oscillator manufactured by the above-described manufacturing method, the monitor electrodes 15a and 15b for measuring the frequency characteristics of the crystal resonator 2 in the mounted state are formed on the bottom surface of the cavity portion 19, and the IC Since the chip 4 is exposed to the outside before mounting, the frequency can be measured from the back surface side (one main surface side) of the ceramic container 1 using the monitor electrodes 15a and 15b, and the upper surface of the ceramic container 1 can be measured. From the side (the other main surface side), vapor deposition for frequency adjustment can be performed.

Further, the monitor electrodes 15a and 15b are finally covered with the IC chip 4. Generally, the silicon chip 41 of the IC chip 4 is at ground potential. That is, a structure having a ground potential exists outside the monitor electrodes 15a and 15b.

Therefore, in the predetermined wiring of the printed wiring board,
Predetermined wiring of the printed wiring board when this crystal oscillator 10 is mounted (especially wiring that passes through the lower surface of the crystal oscillator 10)
There is no generation of unnecessary stray capacitance between the monitor electrodes 15a and 15b.

Therefore, the load capacity of the crystal unit 2 does not change, and a very stable operation of the crystal unit 2 can be secured.

In addition, since the heat aging process for stabilizing the frequency of the crystal unit 2 is performed before the IC chip 4 is mounted in the manufacturing process, the number of heat histories added to the IC chip 4 is reduced. In addition, the aluminum input / output electrode 42 of the IC chip 4 and the connecting member (Au bump 4
The eutectic reaction of Au-Al (cargendard void phenomenon) does not occur at the connection portion with 3). That is, even if the annealing process is performed under the condition that only the frequency stabilization of the crystal unit 2 is focused, the operation of the IC chip 4 and the connection failure do not occur at all.

[0066]

As described above, according to the present invention, the monitor electrode for measuring the frequency of the crystal unit is exposed from the main surface (bottom surface of the cavity) opposite to the surface of the ceramic container in which the crystal unit is arranged. Therefore, the measurement and adjustment work for adjusting the frequency of the crystal unit can be performed very easily.

Further, the crystal unit and the IC chip are separately arranged on the front surface side and the back surface side of the ceramic container, and during the frequency stabilization step (thermal annealing step) of the crystal resonator,
Since the structure can be performed in a state where the IC chip is not attached to the ceramic container, it is possible to prevent malfunction of the IC chip due to heat history and malfunction of the connection portion. In addition, since a defective product is discarded when the crystal unit is mounted, the manufacturing method is economically inexpensive as a whole.

Therefore, the crystal oscillator does not change its oscillation characteristics even when it is surface-mounted on the printed wiring board.

[Brief description of drawings]

FIG. 1 is an external perspective view of a crystal oscillator according to the present invention.

FIG. 2 is a sectional view taken along line XX shown in FIG.

FIG. 3 is a top view of the crystal oscillator of the present invention with the metal lid omitted.

FIG. 4 is a bottom view of the crystal oscillator of the present invention.

5A and 5B are diagrams for explaining the wiring structure of the crystal oscillator of the present invention, in which FIG. 5A is a wiring pattern diagram on the upper surface side of the second ceramic layer, and FIG. 5B is a wiring pattern diagram on the lower surface side of the second ceramic layer. Is.

FIG. 6 is a process drawing for explaining the manufacturing method of the crystal oscillator of the present invention.

FIG. 7 is an external perspective view of a conventional crystal oscillator.

FIG. 8 is a sectional view of a conventional crystal oscillator.

[Explanation of symbols]

1 ... Ceramic container 2 ... Crystal oscillator 3 ... Metal lid 4 ... IC chip 5: Electronic component element 6 ... Coating resin 7 ... Seal ring 15a, 15b ... Monitor electrodes

Continuation of front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) H03H 9/19 H03B 5/32 H03H 9/02 H03H 9/10

Claims (4)

(57) [Claims] 1. A crystal resonator is disposed on the other main surface of a ceramic container having a cavity portion on one main surface of which an IC chip is disposed, and the crystal resonator is hermetically sealed by a ceiling and a metal lid. a crystal oscillator comprising sealed cavity portion located arrangement region of the IC chip
In gap between the bottom surface and the IC chip, and the bottom surface of the cavity portion is connected to the crystal oscillator, the monitor electrodes measuring terminals of the frequency measuring device during inspection of the oscillation characteristic of the crystal oscillator is contacted Contact the input / output electrodes of the IC chip.
Larger than the mounting electrode pad on the bottom of the connected cavity.
A crystal oscillator characterized in that it is formed with a precise area . 2. The crystal oscillator according to claim 1, wherein when the ceramic container is viewed from the one main surface side, the monitor electrode is hidden by the IC chip. 3. The IC chip is mounted on the bottom surface of the cavity through a bump after the oscillation characteristic of the crystal unit is inspected.
Alternatively, the crystal oscillator according to claim 2. 4. The crystal oscillator according to claim 1, wherein the silicon chip of the IC chip has a ground potential.