JP2003115555A - Package for accommodating electronic component - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a cavity that is formed of a ceramic layer at a frame section from falling to the inner peripheral side caused by the pressing of a laminate when forming an insulating substrate. SOLUTION: A package 5 for accommodating electronic components comprises an insulating substrate 1 composed of a frame section ceramic layer 1b for forming a cavity 6 for accommodating electronic components provided the upper surfaces of a flat base part ceramic layer 1a having an electronic component-mounting section on its upper surface and a frame section ceramic layer 1b so that the electronic component-mounting section is surrounded, a wiring conductor 3 that is led from the cavity 6 of the insulating substrate 1 to an external surface, and a lid body 2 that is joined to the upper surface of the frame section ceramic layer 1b. In this case, a frame-like auxiliary ceramic layer 4 is formed on a fitting interface between the inside of the frame section ceramic layer 1b along the inner periphery of the cavity 6 or the frame section ceramic layer 1b and the base section ceramic layer 1a, thus preventing the cavity 6 formed by the frame section ceramic layer 1b from falling to an inner periphery side.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ceramic electronic component housing package having a cavity for housing an electronic component. More specifically, the frame ceramic layer forming the cavity has a good flatness on the upper surface and a lid body. The present invention relates to a package for storing electronic components, which is excellent in hermetic sealing property.

[0002]

2. Description of the Related Art Conventionally, electronic component storage packages for storing electronic components such as semiconductor elements and crystal oscillators generally include aluminum oxide sintered bodies, mullite sintered bodies,
An insulating base made of an electrically insulating material such as an aluminum nitride sintered body or a glass ceramic sintered body, and having a cavity for accommodating electronic parts on the upper surface, and a wiring conductor led from the inside of the cavity to the outer surface of the insulating base. When,
It is composed of a lid joined to the upper surface of the insulating base,
Electronic parts on the bottom of the cavity of the insulating substrate
The inside of the container consisting of the wiring board and the lid is bonded and fixed with an adhesive such as a brazing material, and the lid is joined to the upper surface of the insulating substrate via a sealing material made of glass, resin, brazing, etc. An electronic device is obtained by hermetically accommodating electronic components.

In general, the insulating substrate of such an electronic component storing package has a structure as shown in a sectional view of FIG.
A flat base ceramic layer on which electronic components are mounted
11 and a frame ceramic layer 12 bonded to the upper surface of the base ceramic layer 11 to form a cavity 13 for hermetically housing electronic components. For this insulating substrate, for example, first, a plurality of ceramic green sheets are prepared, and then these ceramic green sheets (hereinafter, referred to as
Frame part ceramic layer 12 out of the green sheet)
Punching is performed to form an opening that becomes a rectangular cavity 13, and then these green sheets are laminated so that the green sheet having the opening that becomes the cavity is located in the upper layer portion. It is manufactured by applying pressure to bring the green sheets into close contact with each other to form a laminated body, and finally firing the laminated body.

Further, in such a package for storing electronic parts, when airtightness is particularly required, it is necessary to firmly bond the lid 14 to the upper surface of the frame ceramic layer 12 through a brazing material. A metallized layer 15 for tight sealing is formed.

[0005]

However, in the conventional package for storing electronic parts, when the green sheets to be the insulating base are laminated and pressed, the frame portion ceramic layer 12 is formed.
However, there is a problem in that the green sheet that becomes the above tends to fall toward the inner peripheral side of the cavity 13, and it is difficult to maintain the flatness of the upper surface of the frame ceramic layer 12. In particular, since the bonding area between the lid 14 and the frame ceramic layer 12 of the insulating base has become extremely small with the recent miniaturization, when the lid 14 is bonded to the insulating base even with a slight inclination. Since a sealing material such as a brazing material does not spread and spread without a gap, it becomes very difficult to tightly adhere the lid 14 to the upper surface of the frame ceramic layer 12 and join it, and a container for hermetically storing electronic components. However, there is a problem in that the airtightness of the device is impaired and the reliability of the electronic device is reduced.

To solve this problem, Japanese Unexamined Patent Publication No. 10-18
In Japanese Patent Laid-Open No. 9810, there is proposed an electronic component storing package in which insulating wirings that compensate for the thickness of the wirings are arranged in the portions where the conductive wirings located immediately below the sealing metallization layer 15 are separated from each other.

According to this electronic component storing package,
By arranging the insulating spacers for compensating the thickness of the wiring, the flatness of the upper surface of the metallizing layer for sealing can be secured even if there is a conductor wiring.

However, in such an electronic component storing package, the step of the metallizing layer for sealing caused by the difference in height between the portion with the conductor wiring and the portion without the conductor wiring can be eliminated, but the green sheet is used. After stacking, each green sheet is almost horizontal from the inner circumference to the outer circumference of the opening that becomes the cavity, so it is not possible to effectively reinforce it from falling inside the cavity.
There is a problem in that it is not possible to effectively prevent the green sheet, which will be the frame portion, from falling into the inside of the cavity due to pressurization of the laminate.

The present invention has been devised in view of the above-mentioned problems of the prior art. An object of the present invention is to ensure that the top surface of the frame ceramic layer of the insulating base is flat and that the lid body is secured to the insulating base without any gaps. An object of the present invention is to provide a package for storing electronic components which can be joined and has excellent airtight reliability.

[0010]

A package for storing electronic parts according to the present invention comprises a plate-shaped base ceramic layer having an electronic part mounting portion on an upper surface thereof, and an upper surface of the base ceramic layer surrounding the electronic component mounting portion. And a wiring conductor led from the cavity of the insulating base to the outer surface of the insulating base, and an upper surface of the frame ceramic layer bonded to the insulating base. In the package for storing electronic parts, which includes a lid body, a frame-like structure is formed inside the frame ceramic layer along the inner circumference of the cavity or at the attachment interface between the frame ceramic layer and the base ceramic layer. It is characterized in that an auxiliary ceramic layer is formed.

Further, the package for storing electronic parts of the present invention is characterized in that, in the above-mentioned structure, a part of the frame-shaped auxiliary ceramic layer is projected into the cavity.

Further, the package for storing electronic parts of the present invention is characterized in that, in the above-mentioned structure, the thickness of the frame-shaped auxiliary ceramic layer is 5 μm or more and 30 μm or less.

Further, in the electronic component storing package of the present invention, in the above structure, the width of the frame-shaped auxiliary ceramic layer is 1 / the width of the region of the upper surface of the frame ceramic layer to which the lid is joined. It is characterized by being 10 or more and 2/3 or less.

In the package for storing electronic parts of the present invention, in the above structure, the angle formed between the inner side surface of the frame ceramic layer and the upper surface of the base ceramic layer is 100 degrees or more and 120 degrees or less. It is a feature.

According to the package for storing electronic parts of the present invention, a frame-shaped auxiliary ceramic is provided inside the frame ceramic layer along the inner periphery of the cavity or at the attachment interface between the frame ceramic layer and the base ceramic layer. Since the layer is formed, the auxiliary ceramic layer can effectively prevent the green sheet, which will be the frame ceramic layer, from falling toward the inside of the cavity when the laminated body of the green sheets is pressed. As a result, the lid can be reliably joined to the upper surface of the insulating base, and the airtightness reliability of the electronic component storage package in which the electronic components are stored can be improved.

When a part of the frame-shaped auxiliary ceramic layer is made to project into the cavity, the projecting part functions as a kind of pillar, so that the green sheet which becomes the frame ceramic layer is inside the cavity. It is possible to more effectively prevent the vehicle from falling toward.

Further, the thickness of the frame-shaped auxiliary ceramic layer is 5
When the width of the frame-shaped auxiliary ceramic layer is 1 μm or more and 2/3 or less of the region where the lid body is joined on the upper surface of the frame ceramic layer, Even when the angle between the inner surface of the layer and the upper surface of the base ceramic layer is 100 degrees or more and 120 degrees or less, the cavity formed by the frame ceramic layer has the inner peripheral side of the cavity when stacking the uppermost layer. To prevent it from falling
The flatness of the sealing area on the top layer of the cavity is preferably 30μ
It can be made extremely small as m or less. As a result, the lid can be reliably joined to the upper surface of the insulating base of the electronic component storage package, and the airtight reliability of the electronic component storage package in which the electronic components are stored can be made extremely good.

As described above, according to the present invention, the upper surface of the frame ceramic layer of the insulating base is flat, so that the lid can be securely bonded to the insulating base without any gaps, and the electronic component storage excellent in airtightness and reliability can be obtained. We can provide a package for you.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a sectional view showing an example of an embodiment of a package for housing electronic parts of the present invention.

In FIG. 1, reference numeral 1 is a base ceramic layer 1a.
And an insulating substrate composed of the frame ceramic layer 1b, 2 a lid, 3 a wiring conductor, and 4 an auxiliary ceramic layer. This insulating substrate 1, lid 2, wiring conductor 3, and auxiliary ceramic layer 4
And constitute a package 5 for storing electronic components (not shown).

The insulating substrate 1 is composed of a glass ceramic sintered body, an aluminum oxide sintered body, a mullite sintered body, a silicon nitride sintered body, an aluminum nitride sintered body, and the like.
A plate-shaped base ceramic layer 1a having an electronic component mounting portion on an upper surface, and a frame portion forming an electronic component storage cavity 6 attached to the upper surface of the base ceramic layer 1a so as to surround the electronic component mounting portion. The ceramic layer 1b and the frame ceramic layer 1b are covered with a sealing metallization layer 7 for bonding the lid 2 to the outermost surface thereof. In addition, the electronic component is bonded and fixed to the electronic component mounting portion on the bottom surface of the cavity 6 via an adhesive such as resin, glass, or brazing material. When a brazing material is used as the adhesive, the wiring conductor 3 is usually formed on the bottom surface of the cavity 6.

The insulating substrate 1 is usually a base ceramic layer 1
It is manufactured by a manufacturing method in which a and the frame portion ceramic layer 1b are formed of the same kind of material and integrally fired.

For example, when the insulating substrate 1 (both the base ceramic layer 1a and the frame ceramic layer 1b) is made of a glass ceramic sintered body, glass powder such as borosilicate glass and ceramic powder such as aluminum oxide are used. An appropriate organic binder, solvent, etc. are added to and mixed with the raw material powder consisting of to make a slurry, and this slurry is made into a green sheet (raw sheet) by adopting the doctor blade method or calender roll method. An appropriate punching process is performed on one of the green sheets that will be the frame ceramic layer 1b to provide an opening for forming the cavity 6 in the center, and then these green sheets are used as the frame ceramic layers 1b. Is located on the upper layer and the cavity 6 is formed by the opening so that the layers are stacked one above the other. Pressurized by contact between the green sheets, finally, it is manufactured by firing at high temperatures.

In the present invention, the frame-shaped auxiliary is provided along the inner circumference of the cavity 6 at the inside of the frame ceramic layer 1b or at the attachment interface between the frame ceramic layer 1b and the base ceramic layer 1a. It is important to form the ceramic layer 4.

When the insulating substrate 1 is manufactured, the frame-shaped auxiliary ceramic layer 4 slightly pushes up the inner periphery (facing the cavity 6) of the portion of the laminated green sheets which will be the frame ceramic layer 1b. The green sheet that becomes the frame ceramic layer 1b has a function of making it difficult to fall toward the inside of the cavity 6, and thus the green sheet that becomes the frame ceramic layer 1b by the pressure applied to the laminated green sheets. Is prevented from falling toward the inside of the cavity 6.

The auxiliary ceramic layer 4 is usually made of the same material as the insulating substrate 1, and for example, the insulating substrate 1
When is made of a glass ceramic sintered body, a ceramic paste having the same composition as the green sheets of the frame ceramic layer 1b and the base ceramic layer 1a is formed on the upper surface of the base ceramic layer 1a along the inner circumference of the cavity 6. It is formed at the attachment interface between the frame ceramic layer 1b and the base ceramic layer 1a by printing in a sheet shape. When the frame ceramic layer 1b is formed by laminating a plurality of green sheets, a ceramic paste having the same composition as the green sheet of the frame ceramic layer 1b is provided between the green sheets along the inner circumference of the cavity 6. By thus printing inside the frame ceramic layer 1b, it is formed inside the frame ceramic layer 1b.

However, the auxiliary ceramic layer 4 is used as the insulating substrate 1.
In order to obtain a different color, a coloring agent such as molybdenum oxide may be added to the above ceramic paste.

Further, it is preferable that a part of the frame-shaped auxiliary ceramic layer 4 is projected into the cavity 6. This is because by projecting the frame-shaped auxiliary ceramic layer 4 into the cavity 6, it is possible to disperse the stress applied to the inner peripheral side of the cavity 6, and thus to the inner peripheral side of the cavity 6 more reliably. This is because it is possible to prevent the collapse of the.

Further, the thickness t of the frame-shaped auxiliary ceramic layer 4 is
Is preferably 5 μm or more and 30 μm or less.

If the thickness t of the auxiliary ceramic layer 4 is smaller than 5 μm, it tends to be difficult to prevent the cavity 6 from collapsing toward the inner peripheral side. There is a tendency that the inner peripheral side rises, making sealing difficult.

The width l of the frame-shaped auxiliary ceramic layer 4
Is preferably 1/10 or more and 2/3 or less of the width L of the region on the upper surface of the frame ceramic layer 1b to which the lid 2 is joined.

In this case, when the width l of the frame-shaped auxiliary ceramic layer 4 exceeds 2/3 of the width L of the region to which the lid 2 is joined, the auxiliary ceramic layer 4 reaches the outer peripheral portion of the cavity 6 without collapse. Therefore, there is a tendency that the sealing metallization layer 7 on the frame ceramic layer 1b becomes uneven and sealing becomes difficult. On the other hand, if it is smaller than 1/10, it tends to be difficult to sufficiently prevent the cavity 6 from falling toward the inner peripheral side.

Further, the angle formed between the inner side surface of the frame ceramic layer 1b and the upper surface of the base ceramic layer 1a is 100 degrees or more.
It is desirable to set it to 20 degrees or less.

When the angle formed between the inner side surface of the frame ceramic layer 1b and the upper surface of the base ceramic layer 1a is less than 100 degrees, the bottom surface of the frame ceramic layer 1b and the base ceramic layer 1
The stress is not sufficiently dispersed at the contact portion with the upper surface of a,
Stress tends to concentrate on the contact portion of the bottom surface, and the insulating base body 1 tends to be easily mechanically broken. On the other hand, when it exceeds 120 degrees, the inclination of the side surface of the frame ceramic layer 1b becomes too large, and sufficient pressure is not applied to the contact portion of the bottom surface when the green sheets are laminated, so that the stackability of the contact portion of the bottom surface is deteriorated. Then, poor adhesion between the green sheets (that is, voids in the insulating substrate 1 after firing) tends to occur.

On the insulating base 1, the surface of the area of the electronic component mounting portion where the electronic components of the base ceramic layer 1a are mounted or its periphery, that is, from the inside of the cavity 6 of the insulating base 1 to the outside of the lower surface of the insulating base 1 and the like. The wiring conductor 3 is led out to the surface.

The wiring conductor 3 is connected to the electrode of the electronic component and functions as a conductive path for leading the electrode to the outside. The electrode of the electronic component is located in the portion of the wiring conductor 3 located inside the cavity 6. A portion connected to a brazing material such as solder or a conductive connecting member such as a bonding wire and led out to the outer surface of the insulating substrate 1 is connected to a circuit wiring of an external electric circuit board through a brazing material such as solder. Connected electrically and mechanically.

The wiring conductor 3 is made of copper, silver, gold, palladium.
If the insulating base 1 is made of a metal material such as tungsten, molybdenum, or manganese, and the insulating substrate 1 is made of a glass ceramic sintered body, copper, silver, palladium, or the like is preferably used.

Further, on the exposed surface of the wiring conductor 3, a metal layer having excellent corrosion resistance such as nickel or gold and having excellent wire bonding property and wettability of the brazing material is applied by a plating method to a thickness of 1 to 20 μm. With this, it is possible to effectively prevent oxidative corrosion of the wiring conductor 3 exposed on the surface, and to firmly bond a brazing material such as solder to the wiring conductor 3, and at the same time, to the outside of the electronic component storing package 5. Bonding to the electric circuit board via the brazing material can be made more reliable.

In order to obtain the insulating substrate 1 having a desired size, a means of cutting the insulating substrate 1 with a cutting device such as a slicer, or a groove-shaped notch is provided in the laminated body in which the green sheets are laminated. After firing and firing, a means of dividing the fired body along the notches can be used.

Further, the frame ceramic layer 1b of the insulating substrate 1
The lid 2 that is joined to the upper surface of the substrate and hermetically seals the electronic component with the insulating base 1 is a metal material such as iron-nickel-cobalt alloy or iron-nickel alloy, or an aluminum oxide sintered body. In the case of an iron-nickel-cobalt alloy, for example, an iron-nickel-cobalt alloy ingot (lump) is subjected to well-known metal working such as rolling or punching to obtain a predetermined shape. It is manufactured by processing into a plate shape having the following dimensions.

The lid 2 can be joined to the upper surface of the frame ceramic layer 1b through a joining material such as a brazing material, glass, or an organic resin.

Table 1 shows the flatness of the encapsulation metallization layer 7 of the package 5 for storing electronic components under various conditions for the thickness t and the width 1 of the auxiliary ceramic layer 4 measured by a laser coordinate measuring machine. It shows the result of measuring the difference between the bottom and the lowest part.

[0044]

[Table 1]

As can be seen from the results in Table 1, according to the electronic component storing package 5 of the present invention, since the frame-shaped auxiliary ceramic layer 3 is formed, the frame portion ceramic layer 1b is formed.
The flatness of the sealing metallization layer 7 formed on the upper surface of
All of them were as good as 30 μm or less.

The thickness t of the frame-shaped auxiliary ceramic layer 3 is
No. of less than 5 μm. Sample No. over 1.2 and 30 μm Flatness of 7 (in the column of sample No. in the table, *
Is larger than 30 μm.

Further, the width l of the frame-shaped auxiliary ceramic layer 3 exceeds 1/10 or more and 2/3 or less of the width L of the region where the lid 2 is joined. Flatness of 13 (Sample N in the table
o. (Indicated by ** in the column) was slightly larger than 30 μm.

Further, Table 2 shows the occurrence rate of the airtight defect of the insulating substrate 1 and the base ceramic layer 1a when the angle between the inner surface of the frame ceramic layer 1b and the upper surface of the base ceramic layer 1a is set to various values. The flatness of the upper surface (represented by the flatness of the bottom surface of the recess) is shown. The flatness of the upper surface of the base ceramic layer 1a was also calculated by measuring the difference between the highest part and the lowest part using a laser coordinate measuring machine.

[0049]

[Table 2]

As can be seen from Table 2, when the angle formed between the inner side surface of the frame ceramic layer 1b and the upper surface of the base ceramic layer 1a is less than 100 degrees, the stress is sufficiently dispersed at the contact portion of the bottom surface. It tends to be difficult, and the bottom surface of the base ceramic layer 1a tends to be deformed, resulting in poor flatness. on the other hand,
If this angle exceeds 120 degrees, the incidence of airtightness tends to increase. This is because, as described above, the inclination of the side surface of the frame ceramic layer 1b becomes too large, and a sufficient pressurizing pressure is not applied to the contact portion on the bottom surface during lamination, so that the stackability of the contact portion on the bottom surface deteriorates. This is because poor adhesion is likely to occur.

Thus, according to the electronic component storage package 5 of the present invention, the electronic component is mounted on the upper surface of the base ceramic layer 1a of the insulating substrate 1 with the electronic component via the adhesive material made of glass, resin, brazing material or the like. The electrodes of the electronic component are connected to the wiring conductors 3 while being fixed by adhesion, and then the lid body 2 is joined to the upper surface of the frame ceramic layer 1b of the insulating base body 1 with a brazing material or the like. An electronic device is obtained by hermetically storing electronic components inside an electronic component storage package 5 including the body 2.

The present invention is not limited to the above-mentioned example of the embodiment, and various modifications can be made without departing from the scope of the present invention.

[0053]

According to the package for housing electronic parts of the present invention, a frame-like structure is formed inside the frame ceramic layer along the inner circumference of the cavity or at the attachment interface between the frame ceramic layer and the base ceramic layer. Since the auxiliary ceramic layer is formed, the auxiliary ceramic layer can effectively prevent the green sheet, which becomes the frame ceramic layer, from falling toward the inside of the cavity when the laminated body of the green sheets is pressed. it can. As a result, the lid can be reliably joined to the upper surface of the insulating base, and the airtight reliability of the electronic component storage package in which the electronic components are stored can be improved.

When a part of the frame-shaped auxiliary ceramic layer is made to project into the cavity, the projecting part functions as a kind of pillar, so that the green sheet to be the frame ceramic layer is formed inside the cavity. It is possible to more effectively prevent the vehicle from falling toward.

The thickness of the frame-shaped auxiliary ceramic layer is 5
When the width of the frame-shaped auxiliary ceramic layer is 1 μm or more and 2/3 or less of the width of the region where the lid body is joined on the upper surface of the frame ceramic layer, Even when the angle between the inner surface of the layer and the upper surface of the base ceramic layer is 100 degrees or more and 120 degrees or less, the cavity formed by the frame ceramic layer has the inner peripheral side of the cavity when stacking the uppermost layer. To prevent it from falling
The flatness of the sealing area on the top layer of the cavity is preferably 30μ
It can be made extremely small as m or less. As a result, the lid can be reliably joined to the upper surface of the insulating base of the electronic component storage package, and the airtight reliability of the electronic component storage package in which the electronic components are stored can be made extremely good.

As described above, according to the present invention, the top surface of the frame ceramic layer of the insulating base is flat, so that the lid can be securely bonded to the insulating base without any gaps, and the electronic component storage excellent in airtightness and reliability can be obtained. I was able to provide a package for.

[Brief description of drawings]

FIG. 1 is a sectional view showing an example of an embodiment of a package for housing an electronic component of the present invention.

FIG. 2 is a cross-sectional view showing an example of a conventional electronic component storage package.

[Explanation of symbols]

1 ... Insulating substrate 1a ... Base ceramic layer 1b..Frame part ceramic layer 2 ... Lid 3 ... Wiring conductor 4 ... Auxiliary ceramic layer 5: Package for storing electronic components 6 ... Cavity 7 ... Metallization layer for sealing

Claims (5)

[Claims] 1. A plate-shaped base ceramic layer having an electronic component mounting portion on an upper surface and a cavity for accommodating an electronic component, which is attached so as to surround the electronic component mounting portion, is formed on an upper surface of the base ceramic layer. A package for storing electronic parts, comprising an insulating base composed of a frame ceramic layer, a wiring conductor led out from the cavity of the insulating base to an outer surface, and a lid joined to an upper surface of the frame ceramic layer, A package for storing electronic components, characterized in that a frame-shaped auxiliary ceramic layer is formed at an attachment interface between the frame ceramic layer and the base ceramic layer. 2. The package for storing electronic parts according to claim 1, wherein a part of the frame-shaped auxiliary ceramic layer is projected into the cavity. 3. The thickness of the frame-shaped auxiliary ceramic layer is 5
2. The thickness is not less than μm and not more than 30 μm.
Package for storing electronic parts as described. 4. The width of the frame-shaped auxiliary ceramic layer is 1/10 or more and 2/3 or less of the width of the region on the upper surface of the frame portion ceramic layer to which the lid is joined. Item 1. The electronic component storage package according to item 1. 5. The angle formed between the inner side surface of the frame ceramic layer and the upper surface of the base ceramic layer is 100 degrees or more 12
The package for storing electronic components according to claim 1, wherein the package is 0 degrees or less.