JP2001237332A - Package for accommodation of electronic part - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a package which can avoid generation of peeling off of a metallized layer after a lid member is joined to a metallic frame brazed to the metallized layer. SOLUTION: In the package for accommodation of an electronic part, a first metallized layer 7a of a frame shape surrounding a mount 1a and a second metallized layer 7b partially thickened on the first metallized layer 7a are coated on an insulating substrate 1 with the mount 1a having an electronic part 4 mounted thereon, a metallized frame 2 surrounding the mount 1a on the first and second metallized layers 7a and 7b is brazed, and a lid member is mounted on the metallized frame. The second metallized layer 7b is provided as biased toward an inner periphery of the first metallized layer 7a. A reservoir for brazing material 8 having a broad width is formed in an outer periphery of the metallized layer 7, and the broad-wide reservoir acts to absorb and lighten a thermal stress after a metallic lid member 3 is welded to the metallic frame 2.

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 electronic components such as a semiconductor device, a piezoelectric vibrator, and a surface acoustic wave device.

[0002]

2. Description of the Related Art Conventionally, a package for accommodating an electronic component such as a semiconductor element or a piezoelectric vibrator has been known as an aluminum oxide sintered compact or an aluminum nitride sintered package as shown in a sectional view of FIG. It is made of electrically insulating material such as sintered body, mullite sintered body, silicon carbide sintered body, silicon nitride sintered body, glass-ceramic, etc.
Insulating base having concave mounting portion 11a for mounting 15
On the upper surface of 11, a frame-shaped metallization layer surrounding the mounting portion 11a
A metal frame 13 for sealing is brazed on the upper surface of the metallized layer 12 via a brazing material 14 such as silver braze, and an electronic component 15 is mounted in the mounting portion 11a. Thereafter, by joining a substantially flat lid 16 to the upper surface of the metal frame 13, the electronic component 15 is hermetically sealed inside, thereby forming an electronic device as a product.

In this conventional package for storing electronic components, the metallized layer 12 is formed of a first metallized layer 12a wider than the metal frame 13 and a first metallized layer 12a.
Second metallized layer partially raised on the center of the
And a metal frame on the first metallized layer 12a and the second metallized layer 12b.
13 is brazed through a brazing material 14 such as silver brazing to form a brazing material 14 between the first metallized layer 12a and the metal frame 13.
The brazing structure which forms the pool of water is suitably adopted. According to this brazing structure, the first metallized layer 12a
Since the pool of the brazing material 14 is formed between the metal frame 13 and the metal frame 13, the brazing strength of the metal frame 13 is increased.

[0004]

However, in the conventional package for storing electronic components, the width of the metallized layer 12 is reduced to, for example, 0.
The width is 3 mm or less, and the width of the metal frame 13 is extremely narrow, 0.25 mm or less. And the second metallization layer 12
Since the width of b is usually 0.05 mm or more, the width of the pool of the brazing material 14 formed on the inner peripheral side and the outer peripheral side of the metallized layer 12 is as narrow as 0.1 mm or less, so that the mounting portion 11a After mounting the electronic components 15, the metal frame
For example, when a cover 16 made of metal is welded to the cover 13 by a seam welding method or the like, the metallized layer is formed by heat shrinkage of the cover 16 made of metal and the metal frame 13 in a cooling process after welding.
The pool of the brazing material 14 cannot sufficiently absorb and mitigate the thermal stress applied to pull the outer peripheral portion of the metal substrate 12 inward. As a result, the outer peripheral portion of the metallized layer 12
And the airtight reliability of an electronic device using the conventional electronic component storage package is greatly impaired.

The present invention has been made in view of the problems of the prior art, and an object of the present invention is to provide a method in which a lid and a metal frame are thermally contracted after the lid is joined to the metal frame. An object of the present invention is to provide an electronic component housing package having high hermetic reliability, in which the metallized layer 12 does not peel off from the insulating base 11 even when a generated thermal stress is applied.

[0006]

According to a first aspect of the present invention, there is provided an electronic component housing package comprising: a first metallization layer having a frame shape surrounding a mounting portion on a surface of an insulating base having a mounting portion on which an electronic component is mounted; And a second metallized layer partially raised on the first metallized layer, and a metal frame surrounding the mounting portion is brazed on the first and second metallized layers, and the metal frame is formed. An electronic component storage package in which a lid is attached to a body, wherein the second metallized layer is provided so as to be biased toward the inner periphery of the first metallized layer.

According to the electronic component housing package of the present invention, since the second metallized layer is provided so as to be deflected toward the inner periphery of the first metallized layer, the gap between the metal frame and the first metallized layer is provided. The width of the pool of brazing material formed on the outer peripheral side of the metallized layer can be made wider, and as a result, heat applied to pull the outer peripheral portion of the first metallized layer inward after welding of the lid body is applied. The stress can be favorably absorbed and alleviated by the brazing material pool on the outer peripheral side having a wide width.

[0008]

Next, the present invention will be described with reference to the accompanying drawings.

FIG. 1 is a cross-sectional view showing an example of an embodiment of an electronic component storage package according to the present invention, wherein 1 is an insulating base, 2 is a metal frame, and 3 is a lid. These mainly constitute a container that hermetically accommodates the semiconductor element 4.

The insulating substrate 1 has a concave mounting portion 1a for mounting the electronic component 4 at the center of the upper surface, and the electronic component 4 is mounted and fixed on the mounting portion 1a.

Such an insulating substrate 1 is made of a sintered body of aluminum oxide, a sintered body of aluminum nitride, a sintered body of mullite, a sintered body of silicon carbide, a sintered body of silicon nitride or glass.
If it is made of an electrically insulating material such as ceramics, and is made of, for example, an aluminum oxide sintered body, a suitable binder or solvent is added to and mixed with raw material powder such as aluminum oxide, silicon oxide, calcium oxide, or magnesium oxide. A plurality of ceramic green sheets are obtained by forming a sheet and adopting a conventionally known doctor blade method or the like to form a sheet. Thereafter, each of these ceramic green sheets is subjected to an appropriate punching process. It is manufactured by laminating these on top and bottom and firing at a temperature of about 1600 ° C.

A plurality of metallized wiring conductors 5 extending from the bottom surface of the mounting portion 1a to the lower surface via the side surface are formed on the insulating base 1. Metallized wiring conductor 5
Functions as a conductive path for electrically connecting each electrode of the electronic component 4 mounted on the mounting portion 1a to an external electric circuit,
Each electrode of the electronic component 4 is electrically connected to a bottom portion of the mounting portion 1a via a conductive bonding material 6 such as solder or a conductive resin. Is connected to an external electric circuit through the electric connection means.

The metallized wiring conductor 5 is made of metallized metal powder such as tungsten, molybdenum, copper, silver, etc., and insulates a metal paste obtained by adding a suitable organic binder and solvent to a metal powder such as tungsten. A ceramic green sheet serving as the base 1 is printed and applied in a predetermined pattern by a screen printing method, and this is applied to the insulating base 1.
By firing together with the ceramic green sheet laminate to be formed, the insulating base 1 is formed so as to be led out from the bottom surface of the mounting portion 1a to the lower surface via the side surface.

Note that the surface of the metallized wiring conductor 5
In order to effectively prevent the metallized wiring conductor 5 from being oxidized and corroded, and to improve the connectivity between the metallized wiring conductor 5 and the electrical connection means such as the conductive bonding material 6 and solder, it is usual that A nickel plating layer having a thickness of about 1 to 10 [mu] m and a gold plating layer having a thickness of about 0.1 to 3.0 [mu] m are sequentially applied by a conventionally known electrolytic plating method or electroless plating method.

Further, the mounting portion 1 is provided on the upper surface of the insulating base 1.
A frame-shaped metallized layer 7 made of metallized metal powder of tungsten, molybdenum, copper, silver or the like is formed so as to surround a. The metallized layer 7 functions as a base metal for joining the metal frame 2 to the insulating base 1, and has a first metallized layer 7 a having a width larger than the width of the metal frame 2 joined thereto, Metallized layer 7a
And a second metallized layer 7b having a width narrower than the width of the metal frame 2 and partially laminated on the upper side. On the upper surfaces of the first metallized layer 7a and the second metallized layer 7b, a metal frame 2 surrounding the mounting portion 1a is brazed via a brazing material 8 such as silver braze. A pool of the brazing material 8 having a thickness corresponding to the height of the second metallized layer 7b is formed between the first metallized layer 7a and the first metallized layer 7a.

In the electronic component housing package of the present invention, it is important that the second metallized layer 7b is provided so as to be deflected toward the inner periphery of the first metallized layer 7a. Second metallized layer 7b is first metallized layer 7a
The metal frame 2 and the first metallized layer 7a are provided on the outer peripheral side of the metallized layer 7 even if the width of the metallized layer 7 is narrow, for example, 0.3 mm or less. And the width of the pool of the brazing material 8 formed between them can be made wider than 0.1 mm. As described above, by making the width of the pool of the brazing material 8 formed between the metal frame 2 and the first metallized layer 7a wider than 0.1 mm on the outer peripheral side of the metallized layer 7, the metal frame is formed. After welding the lid 3 made of, for example, a metal to the upper surface of the metallization layer 7 by a seam welding method or the like, even if a thermal stress that pulls the outer peripheral portion of the metallized layer 7 inward by the metal frame 2 and the lid 3 is applied, The thermal stress is well absorbed and dispersed by the accumulation of the brazing material 8 having a width exceeding 0.1 mm formed on the outer peripheral side of the metallized layer 7, so that the metallized layer 7 can be effectively prevented from peeling off from the insulating base 1. . Therefore, according to the electronic component storage package of the present invention, the hermetic sealing of the container is always maintained,
Thereby, the electronic component 4 housed therein can be operated normally and stably for a long period of time.

If the width from the outer periphery of the first metallized layer 7a to the second metallized layer 7b is less than 0.13 mm, the metal frame 2 and the first metallized layer 7
a width of the pool of the brazing material 8 formed between
Therefore, after the cover 3 is brazed to the metal frame 2, heat applied by the metal frame 2 and the cover 3 to pull the outer peripheral portion of the metallized layer 7 inward is applied. It tends to be difficult to absorb and disperse the stress well. Therefore, the width from the outer periphery of the first metallized layer 7a to the second metallized layer 7b is preferably 0.13 mm or more. On the other hand, on the inner peripheral side of the metallized layer 7, a large stress is not applied so as to peel the metallized layer 7 from the insulating base 1, so that the width of the pool of the brazing material 8 formed on the inner peripheral side is not increased. May be narrow. Therefore, the width from the inner periphery of the first metallized layer 7a to the second metallized layer 7b may be less than 0.13 mm, but may be 0.05 mm or more in order to firmly join the metallized layer 7 and the metal frame 2. preferable.

Further, if the thickness of the first metallized layer 7a is less than 10 μm, the adhesion strength of the first metallized layer 7a to the insulating base 1 tends to be weak, while
If the thickness exceeds 20 μm, it tends to be difficult to firmly laminate the second metallized layer 7b on the upper surface of the first metallized layer 7a. Therefore, the first metallized layer 7a
Is preferably in the range of 10 to 20 μm. If the thickness of the second metallized layer 7b is less than 10 μm, it becomes impossible to form a pool of the brazing material 8 having a sufficient thickness between the metal frame 2 and the first metallized layer 7a. If the thickness exceeds 50 μm, the strength of the upper surface of the second metallized layer 7b becomes weak, and the metal frame 2
Tends to be difficult to braze firmly to the metallized layer 7. Therefore, the thickness of the second metallized layer 7b is preferably in the range of 10 to 50 μm. Also,
When the width of the second metallized layer 7b is less than 0.05 mm,
It tends to be difficult to form this in a predetermined stable shape. On the other hand, if it exceeds 0.15 mm, the accumulation of the brazing material 8 having a sufficient width between the metal frame 2 and the first metallized layer 7a. Tends to be difficult to form. Therefore, the width of the second metallized layer 7b is preferably in the range of 0.05 to 0.15 mm.

The metallized layer 7 is formed by applying a well-known screen printing method on a ceramic green sheet serving as the insulating substrate 1 by adding a metal paste obtained by adding a suitable binder and solvent to a metal powder such as tungsten. Then, the pattern for the first metallized layer 7a and the pattern for the second metallized layer 7b are printed and applied in two parts, and are fired at the same time as the ceramic green sheet laminate to be the insulating base 1. 1 is attached in a predetermined shape so as to surround the mounting portion 1a.

In order to effectively prevent the metallized layer 7 from being oxidized and corroded and to improve the bonding between the metallized layer 7 and the brazing material 8, the surface of the metallized layer 7 is usually placed on the surface. A nickel plating layer having a thickness of about 1 to 10 μm is sequentially applied by a conventionally known electrolytic plating method or electroless plating method.

The metal frame 2 brazed to the metallized layer 7 via a brazing material 8 such as silver brazing is made of a metal such as an iron-nickel alloy or an iron-nickel-cobalt alloy. Functions as a base metal member for bonding the substrate to the insulating base 1. Then, the lid 3 is placed on the metal frame 2 and, for example, when the lid 3 is made of metal, the lid 3 is joined to the metal frame 2 by welding them by a seam welding method. You. Such a metal frame 2 is formed by punching a plate material made of an iron-nickel alloy, an iron-nickel-cobalt alloy, or the like into a predetermined frame shape. The foil-like brazing material is interposed and then brazed on the metallized layer 7 via the brazing material 8 by heating and melting the brazing material.

The metal frame 2 is usually formed with a radius of curvature of about 5 to 50 μm at the corner between one main surface and the inner and outer surfaces by punching. If the brazing is performed so that the side faces the metallized layer 7, the roundness allows the pool of the brazing material 8 to be further increased. Therefore, the metal frame 2
It is preferable that brazing is performed so that a rounded side formed by punching faces the metallized layer 7.
In addition, on the exposed surfaces of the metal frame 2 and the brazing material 8, in order to prevent the metal frame 2 and the brazing material 8 from being oxidized and corroded,
Nickel plating layer with thickness of about 1 to 10 μm and thickness
A gold plating layer having a thickness of about 0.1 to 3.0 μm is usually sequentially applied after brazing, usually by a known electroplating method or electroless plating method.

On the other hand, the lid 3 is made of, for example, an iron-nickel alloy or an iron-nickel-cobalt alloy having a thickness of 0.1 mm.
It is a flat plate of a degree, and is manufactured in a predetermined shape by a punching die of an iron-nickel alloy plate or an iron-nickel-cobalt alloy plate.

Thus, according to the electronic component housing package of the present invention, the electronic component 4 is mounted on the mounting portion 1a of the insulating base 1 by electrically connecting each electrode to the metallized wiring conductor 5. After mounting and fixing via material 6,
To provide an electronic device having excellent hermetic reliability by welding a lid body to a metal frame body brazed to an insulating base body by a seam welding method or the like and hermetically sealing an electronic component therein. Can be.

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, in the above-described embodiment, The metal frame 2 was brazed to a substantially central portion of the metallized layer 7, but as shown in the sectional view of FIG.
Is biased toward the inner periphery of the metallized layer 7 so as to increase the width from the outer periphery of the metallized layer 7 to the metal frame 2, thereby providing a space between the side surface of the metal frame 2 and the metallized layer 7. Alternatively, a pool of the brazing material 8 may be provided to further braze the metal frame 2 to the metallized layer 7 more firmly.

[0026]

According to the electronic component housing package of the present invention, since the second metallized layer is provided so as to be deviated toward the inner periphery of the first metallized layer, a metal brazed thereon is provided. The width of the pool of the brazing material formed between the frame and the first metallized layer can be increased on the outer peripheral side of the metallized layer, and as a result, after joining the lid to the metal frame, Even if thermal stress is applied by the frame and lid to pull the outer peripheral portion of the first metallized layer inward, the stress is well absorbed by the pool of the wide brazing material formed on the outer peripheral side of the metallized layer. The metallized layer does not peel off as a result,
An electronic component storage package having excellent airtight reliability can be provided.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating an example of an embodiment of an electronic component storage package according to the present invention.

FIG. 2 is a sectional view showing another example of the embodiment of the electronic component storage package of the present invention.

FIG. 3 is a cross-sectional view showing a conventional electronic component housing package.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Insulating base 1a ... Mounting part 2 ... Metal frame 3 ... Lid 4 ... Electronic components 7 ... Metallized layer 7a ... First metallized layer 7b ... second metallized layer 8 ... brazing material

Claims (2)

[Claims] A first metallization layer having a frame shape surrounding the mounting portion, and a portion protruding over the first metallization layer on a surface of the insulating base having a mounting portion on which the electronic component is mounted, on the mounting portion side. And a metal frame surrounding the mounting portion is brazed on the first and second metalized layers, and a lid is attached to the metal frame. An electronic component storage package, wherein the second metallized layer is provided so as to be biased toward an inner periphery of the first metallized layer. 2. The electronic component storage package according to claim 1, wherein a distance from an outer periphery of the first metallized layer to an outer periphery of the second metallized layer is 0.13 mm or more.