JP2002252538A - Package for housing quartz-oscillator and quartz-device using it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a package for housing quartz-oscillator which can prevent the occurrence of such a problem that the vibration of a quartz-oscillator housed in the package becomes unstable due to noise entering into the wiring layer of the package from an external electric circuit. SOLUTION: This package for housing quartz-oscillator is composed of a main body 1 having a mounting section 1a on which the quartz-oscillator 5 is mounted and the wiring layer 2 led out to the external surface of the main body 1 from the mounting section 1a, and a lid body 3 which is fitted to the main body 1 and hermetically seals the mounting section 1a. At least part of the wiring layer 2 is made to contain ferrite powder.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a package for accommodating a crystal oscillator for accommodating a crystal oscillator, and a crystal device having a crystal oscillator hermetically accommodated in the package for accommodating the crystal oscillator. .

[0002]

2. Description of the Related Art A quartz device used as a reference source for time and frequency in an information processing device such as a computer or an electronic device such as a cellular phone generally has an electrode for applying a voltage formed on a square plate-shaped quartz substrate. Is formed by hermetically enclosing the crystal unit thus formed in a package for accommodating the crystal unit.

Conventionally, the crystal resonator housing package is made of an electrically insulating material such as an aluminum oxide sintered body, and has a recess for forming a cavity for housing the crystal resonator in the center of the upper surface, and a surface of the recess. A base having a wiring layer made of a metal material such as a refractory metal such as tungsten or molybdenum, which is led out from the metal to the outer surface; And a lid made of a ceramic material such as a body.

[0004] Then, the electrode of the crystal unit is bonded to the wiring layer exposed on the inner surface of the concave portion of the substrate and the peripheral surface of the substrate through a conductive adhesive or the like, whereby the crystal unit is bonded and fixed in the concave portion. The lid is then electrically connected to the wiring layer, and then a lid is attached to the upper surface of the base by bonding means such as bonding with an adhesive or seam welding. A crystal device as a product is completed by housing the child in an airtight manner.

When the lid is attached to the substrate by seam welding, usually, a frame-shaped metallizing layer for brazing is formed in advance around the concave portion of the substrate, and a metal frame is brazed to the metallizing layer. Then, the lid is seam-welded to the metal frame.

The mounting of the crystal device on an external electric circuit board is performed by connecting a wiring layer led out to the outer surface of the base to the external electric circuit board via a conductive connecting material such as solder. The crystal resonator is electrically connected to an external electric circuit via a wiring layer, and vibrates at a predetermined frequency according to a voltage applied from the external electric circuit.

[0007]

However, in recent years,
2. Description of the Related Art With the rapid increase in performance of information processing devices and electronic devices, the frequency of electric signals propagating in external electric circuits has been increased, and a large amount of noise has been generated when electric signals propagate in external electric circuits. For this reason, when a crystal device is used in an information processing device or an electronic device whose performance is increasing, noise easily enters the wiring layer of the crystal device from an external electric circuit. The voltage applied to the crystal fluctuates, and the fluctuation of the voltage causes the oscillation of the crystal oscillator to become unstable, and the frequency of the crystal device fluctuates or malfunctions. There is a problem that it becomes impossible to operate it.

The present invention has been devised in view of the above-mentioned conventional problems, and has as its object to satisfactorily absorb and remove noise entering a wiring layer from an external electric circuit and to apply a voltage applied to a quartz oscillator. An object of the present invention is to provide a package for accommodating a crystal oscillator, which can always operate the crystal oscillator normally while keeping the constant, and a crystal device using the same.

[0009]

According to the present invention, there is provided a base having a mounting portion on which a quartz oscillator is mounted, and having a wiring layer led out from the mounting portion to the outer surface; A package for accommodating a crystal oscillator, comprising a lid for hermetically sealing the mounting portion, wherein at least a part of the wiring layer contains ferrite powder.

The present invention also provides a crystal device in which a crystal unit is hermetically housed in the crystal unit housing package, and more specifically, a crystal unit mounted on a base of the crystal unit housing package. The present invention relates to a crystal device in which a resonator is mounted and fixed and electrodes of the crystal unit are electrically connected to the wiring layer.

According to the crystal resonator housing package of the present invention and the crystal device using the same, since at least a part of the wiring layer contains ferrite powder, noise enters the wiring layer from an external electric circuit. Even if the noise is converted to heat energy by the ferrite powder contained in the wiring layer and absorbed and removed, it hardly acts on the electrodes of the crystal unit, and as a result, it is applied to the electrodes of the crystal unit. Voltage can be kept constant, and the crystal oscillator can always be operated at a normal frequency, and the information processing device such as a computer and the electronic device such as a mobile phone on which the crystal device is mounted can always be normally operated. Becomes

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a package for storing a crystal unit and a crystal device according to the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 is a sectional view showing an embodiment of a package for accommodating a crystal resonator of the present invention and a crystal device using the same.

In FIG. 1, 1 is a base, 2 is a wiring layer, 3
Is a lid. The base 1, the wiring layer 2, and the lid 3 form a crystal resonator housing package 4. The crystal resonator 5 is placed in a container formed of the base 1 and the lid 3 of the crystal resonator housing package 4. The crystal device 6 is formed by being housed in an airtight manner.

The substrate 1 is made of, for example, SiO ₂ —Al ₂ O
_{3 -MgO-ZnO-B 2 O} 3 based crystalline glass, Al ₂ O _3, or the
Is formed of an aluminum oxide sintered body of about 90% by weight, and a concave portion 1a serving as a space for mounting and housing the quartz oscillator 5 is provided on the upper surface thereof, and the quartz oscillator is provided in the recess 1a. 5 are mounted and accommodated.

The substrate 1 is made of, for example, SiO ₂ —Al ₂ O
If made of _{3 -MgO-ZnO-B 2 O} 3 based crystalline glass, SiO _2: 40 to 46 wt%, Al ₂ O _3: 25~3
0% by weight, MgO: 8 to 13% by weight, ZnO :: 6 to 9
B ₂ O ₃ : 8 to 11% by weight of raw material powder, an appropriate organic binder, a solvent, a plasticizer, a dispersant, and the like are added and mixed to form a slurry, and this slurry is subjected to a conventionally known doctor blade method. A plurality of green sheets (green glass ceramic sheets) are obtained by forming into a sheet shape, and then the green sheet is subjected to an appropriate punching process to form a predetermined shape, and is laminated on the upper and lower sides at about 1000 ° C.
It is manufactured by firing at a temperature of

In the substrate 1, the wiring layer 2 is extended from the surface of the concave portion 1a to the outer surface, and the electrode of the crystal unit 5 is electrically connected to the conductive adhesive 7 at the portion of the wiring layer 2 exposed on the surface of the concave portion 1a. The portion led out to the outer surface is connected to the wiring conductor of the external electric circuit board via a brazing material such as solder.

The wiring layer 2 functions to electrically connect the crystal oscillator 5 housed in the recess 1a to the wiring conductor of the external electric circuit board, and is made of copper, silver, gold, tungsten, molybdenum or the like. For example, in the case of copper, which is formed of a metal material, a metal paste obtained by adding and mixing an appropriate organic solvent, an organic binder, and the like to copper powder is screen-printed on the surface of a green sheet serving as the substrate 1 by a method such as screen printing. Is formed by printing and applying in a predetermined pattern.

If the exposed surface of the wiring layer 2 is covered with a plating layer (not shown) made of a metal having good corrosion resistance such as nickel and gold and good wettability of a brazing material,
Oxidation and corrosion of the wiring layer 2 can be satisfactorily prevented, and the wettability of a brazing material such as solder to the wiring layer 2 can be improved, and the connection of the wiring layer 2 to the wiring conductor of the external electric circuit board can be improved. It can be made easier and more reliable. Accordingly, the wiring layer 2 has an exposed surface formed of a plating layer of nickel, gold, or the like, for example, a nickel or nickel alloy plating layer having a thickness of 1 μm to 10 μm and a gold plating layer having a thickness of 0.1 to 3 μm. It is preferred to coat with.

When the surface of the wiring layer 2 is coated with a plating layer of nickel, gold, or the like, the outermost surface has an arithmetic average roughness (Ra) of 1.5 μm or less and a root mean square roughness (Rm).
If s) is set to 1.8 μm or less, the reflectivity of light on the outermost surface becomes 40% or more, and when the crystal unit 5 is bonded to the wiring layer 2 via a conductive adhesive, the work of positioning and the like is performed. It will be easier. Therefore, when the surface of the wiring layer 2 is covered with a plating layer of nickel, gold, or the like, the arithmetic mean roughness (Ra) of the outermost surface is 1.5 μm or less, and the root mean square roughness (Rm) is used.
It is preferable that s) is 1.8 μm or less.

Further, the arithmetic average roughness (R) of the outermost surface of the plating layer made of nickel, gold or the like which covers the surface of the wiring layer 2
a) is 1.5 μm or less, root mean square roughness (Rms)
Is adjusted to 1.8 μm or less, the wiring layer 2 is immersed in an electrolytic nickel plating solution in which a brightener such as a sulfur compound is added to a conventionally known watt bath, and a nickel plating layer is deposited on the surface of the wiring layer 2. Thereafter, the immersion is performed by dipping in a cyan-based electrolytic gold plating solution to deposit a gold plating layer on the surface of the nickel plating layer.

In the present invention, it is important that the wiring layer 2 contains ferrite powder.

If the wiring layer 2 contains ferrite powder, noise enters the wiring layer 2 from an external electric circuit, and when the noise propagates through the wiring layer 2, the noise is selectively generated by the ferrite powder. , And is absorbed and removed. As a result, noise hardly acts on the electrodes of the crystal unit 5, whereby the voltage applied to the electrodes of the crystal unit 5 becomes constant, and the crystal unit 5 is always It is possible to operate at a normal frequency, and to always normally operate an information processing apparatus such as a computer and an electronic apparatus such as a mobile phone on which the crystal device is mounted.

The ferrite contained in the wiring layer 2 is N
i-Zn ferrite (Ni-Cu-Zn-Fe-O),
Ferrox planarizer type ferrite (Ba-Sr-Co-
Zn-Fe-O) or the like is preferably used. If the frequency of the electric signal is less than 300 MHz, use Ni-Zn ferrite. If the frequency of the electric signal is 300 MHz or more, use ferro-planar ferrite. Thus, noise propagating in the wiring layer 2 can be selectively and favorably absorbed and removed.

The ferrite powder is contained in the wiring layer 2 by adding the ferrite powder to the metal paste for forming the wiring layer 2 in advance and mixing.

Further, if the amount of the ferrite powder contained in the wiring layer 2 is less than 10% by weight,
If the noise exceeds 70% by weight, the conduction resistance of the wiring layer 2 increases, and a predetermined voltage is applied to the electrode of the crystal unit 5 via the wiring layer 2. It will be difficult to do. Therefore, the amount of the ferrite powder contained in at least a part of the wiring layer 2 is preferably set in the range of 10 to 70% by weight.

Further, when the particle size of the ferrite powder is less than 0.5 μm, the specific surface area increases, and during firing, the reactivity with the raw material powder such as SiO ₂ of the substrate 1 increases, the magnetism decreases, and noise is reduced. It becomes difficult to absorb and remove it. Therefore, the ferrite powder preferably has a particle size of 0.5 μm or more, and more preferably 0.5 μm to 10 μm.

Further, a quartz oscillator 5 is adhered and fixed to the wiring layer 2 via a conductive adhesive 7, and at the same time,
Are electrically connected to the wiring layer 2.

The conductive adhesive 7 is generally formed by adding a conductive powder such as a silver powder to a thermosetting resin such as an epoxy resin. The uncured thermosetting resin is positioned and set via an uncured conductive adhesive obtained by adding a conductive powder to the uncured thermosetting resin. 1a is fixed at a predetermined position, and the electrode of the crystal unit 5 is electrically connected to the wiring layer 2.

The substrate 1 on which the crystal unit 5 is adhered and fixed via a conductive adhesive 7 is also provided with a lid 3 on its upper surface, whereby the interior of the container comprising the base 1 and the lid 3 is formed. The crystal oscillator 5 is housed in an airtight manner, and the crystal device 6
Becomes

The lid 3 is made of a metal material such as an iron-nickel-cobalt alloy or an iron-nickel alloy, or a ceramic material such as an aluminum oxide sintered body. It is formed by subjecting ingots (lumps) to known metal processing such as rolling and punching.

The attachment of the lid 3 to the base 1 can be performed by a method using a joining material such as a brazing material, glass, an organic resin adhesive, or a welding method such as seam welding. When the cover 3 is attached by seam welding, a frame-shaped brazing metallization layer 1 is usually formed around the concave portion 1a of the base 1.
0 is deposited in the same manner as the wiring layer 2 and
A metal frame 11 is brazed to the brazing metallization layer 10 via a brazing material such as silver brazing. Thereafter, the metal lid 3 is placed on the metal frame 11 and the metal This is performed by seam welding the outer edge. In this case, if the metal frame 11 is formed with a radius of curvature of 5 to 30 μm at the corner between the upper surface and the side surface, no burr is formed on the upper surface of the metal frame 11. When the lid 3 is welded to the upper surface of the metal frame 11 by seam welding, the two can be joined together in a highly reliable, airtight and strong manner. Therefore, it is preferable that the metal frame 11 be rounded at the corner between the upper surface and the side surface with a radius of curvature of 5 to 30 μm.

Further, if the metal frame 11 is formed to have a radius of curvature of 40 to 80 μm at the corner between the lower surface and the side surface, the metal frame 11 is brazed to the metallizing layer 10. When a brazing material is joined to the metal frame, a space is formed between the metallizing layer 10 for brazing and the corner on the lower surface side of the metal frame 11, and a large pool of the brazing material is formed in the space. Metallized layer 10 for brazing body 11
Bonding to is strengthened. Accordingly, in order to firmly join the metal frame 11 to the brazing metallization layer 10 via a brazing material, the corner between the lower surface and the side surface of the metal frame 11 should have a radius of curvature of 40 to 80 μm. It is preferable to form them.

According to the package 4 for accommodating the quartz oscillator described above, the quartz oscillator 5 is mounted and fixed in the recess 1a of the base 1 via the conductive adhesive 7 and the upper surface of the base 1 is closed so as to cover the recess 1a. The lid 3 is attached to the
Is airtightly accommodated, a crystal device 6 as a final product is completed.

It should be noted that the present invention is not limited to the above-described embodiment, and various changes can be made without departing from the scope of the present invention. For example, as shown in FIG.
If the projections 8 are formed in a part of the wiring layer 2, the projections 8
Serves as a spacer to secure a certain space between the wiring layer 2 and the crystal unit 5, and a sufficient amount of the conductive adhesive 7 enters into this space to adhere and fix the crystal unit 5 to the wiring layer extremely strongly. can do.

In the above-described package for accommodating a quartz oscillator, a recess 1a is provided in the base 1, and the quartz oscillator 5 is provided in the recess 1a.
As shown in FIG. 3, a quartz oscillator 5 is mounted and fixed on a flat base 1 and the fixed quartz oscillator 5 is hermetically sealed with a bowl-shaped lid 3 as shown in FIG. The present invention can also be applied to a package for accommodating a crystal resonator that is sealed.

[0036]

According to the package for accommodating the crystal resonator of the present invention and the crystal device using the same, since the ferrite powder is contained in at least a part of the wiring layer, noise is generated from the external electric circuit to the wiring layer. Even if you get in,
The noise is converted to thermal energy by the ferrite powder contained in the wiring layer, absorbed and removed, and hardly acts on the electrodes of the crystal unit. As a result, the voltage applied to the electrodes of the crystal unit is As a result, the crystal oscillator can always be operated at a normal frequency, and the information processing apparatus such as a computer and the electronic device such as a mobile phone on which the crystal device is mounted can always be normally operated.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing an embodiment of a package for accommodating a crystal resonator of the present invention and a crystal device using the same.

FIG. 2 is a cross-sectional view of a principal part showing another embodiment of a package for accommodating a crystal resonator of the present invention and a crystal device using the same.

FIG. 3 is a cross-sectional view showing another embodiment of a package for accommodating a crystal resonator of the present invention and a crystal device using the same.

[Description of Signs] 1 ··· Base 1a ··· Recess 2 ······ Wiring layer 3 ······· Lid 4 ····· Package for housing crystal resonator 5 ··· ..Crystal vibrator 6 ... Crystal device 7 ... Conducting adhesive 10 ........ Metalizing layer for brazing 11 ... Metal frame

Claims (2)

[Claims] 1. A base having a mounting portion on which a quartz oscillator is mounted, and having a wiring layer led out from the mounting portion to the outer surface, and attached to the base to hermetically seal the mounting portion. A package for accommodating a crystal oscillator, comprising: a lid body; and a ferrite powder contained in at least a part of the wiring layer. 2. A crystal resonator is mounted and fixed on a mounting portion provided on a base of the crystal resonator housing package according to claim 1, and electrodes of the crystal resonator are electrically connected to the wiring layer. A quartz device characterized by the following.