JP2002353350A - Package for storing electronic part - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a package for storing an electronic part having a metallized layer, on which a metal frame body is brazed, which is free from abrasion and has achieved a highly reliable hermeticity. SOLUTION: In the package for storing an electronic part comprising a mounting portion 1a upon a top face of which an electronic part 6 is mounted; an insulating substrate 1 having a substantially rectangular metallized layer 5 for brazing which surrounds the mounting portion 1a; an substantially rectangular metal frame body 2 which is formed by stamping a rolled metal sheet and mounted on the metallized layer 5 for brazing so as to surround the mounting portion 1a; and a metal lid 3 which is bonded on the metal frame body. the metal frame body 2 is stamped in such a manner that a short side thereof is almost in parallel with the rolling direction of the rolled metal sheet.

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, as shown in a perspective view in FIG. 3, a small electronic component housing package for housing electronic components such as a semiconductor element and a piezoelectric vibrator is made of aluminum oxide sintered body or aluminum nitride. Sintered body, mullite sintered body,
It is made of an electrically insulating material such as glass-ceramics, and has a concave mounting portion for mounting the electronic component 16 at the center of the upper surface.
An insulating substrate 11 having a plurality of metallized wiring conductors 14 extending from the inside of the mounting portion 11a to the outer peripheral portion of the lower surface and a brazing metallization layer 15 attached on the upper surface so as to surround the mounting portion 11a; An approximately square frame-shaped metal frame made of a metal such as an iron-nickel-cobalt alloy joined to the brazing metallization layer 15 via a brazing material such as silver-copper brazing so as to surround the mounting portion 11a. It comprises a body 12 and a metal lid 13 made of a metal such as an iron-nickel-cobalt alloy joined to the upper surface of the metal frame 12 by a seam welding method or the like.

According to the conventional package for storing electronic components, the electronic component is mounted on the bottom surface of the mounting portion 11a of the insulating base 11.
16 and the electrodes of this electronic component 16
a, and electrically connected to the metallized wiring conductor 14 in FIG. 1A through an electrical connection means such as solder, conductive resin, bonding wire, or the like. The electronic component 16 is hermetically sealed inside a container including the insulating base 11, the metal frame 12, and the metal lid 13 by welding by a method, thereby forming an electronic device as a product.

[0004] The metal frame 12 is manufactured by punching a rolled metal plate made of an iron-nickel-cobalt alloy or the like by a punching die. The metal plate had been punched out so that its long side was substantially parallel to the rolling direction.

[0005]

However, with the recent miniaturization of electronic devices, electronic component housing packages for housing electronic components have also been miniaturized, so that the metal frame 12 would have been brazed. The width of the metallization layer 15 for attachment is becoming extremely narrow, about 0.2 to 0.5 mm. Then, when the metal lid 13 is welded to the metal frame 12 brazed to the narrow brazing metallization layer 15 by the seam welding method, the metal frame 12 and the metal which have greatly expanded due to the heat of welding are formed. The thermal stress generated when the lid 13 undergoes a large thermal contraction during the cooling process after welding and the stress generated during brazing overlap and act on the metallizing layer 15 for brazing, so that the metallizing layer 15 for brazing is formed.
Peeling occurs, and as a result, there is a problem that the airtight reliability of the electronic device using the conventional electronic component housing package is greatly impaired.

The present invention has been made in view of the above-mentioned conventional problems, and an object of the present invention is to firmly join a metal frame and a brazing metallization layer and peel off the brazing metallization layer. It is an object of the present invention to provide an electronic component housing package having high hermetic reliability with no occurrence of cracks.

[0007]

According to the present invention, there is provided an electronic component storage package comprising: a mounting portion on which an electronic component is mounted; and a substantially rectangular frame-shaped brazing metallizing layer surrounding the mounting portion. On the brazing metallization layer, a substantially rectangular frame-shaped metal frame formed by punching a rolled metal plate is attached so as to surround the mounting part, and the metal lid is joined to the metal frame. In the electronic component storage package according to the present invention, the metal frame is punched out such that a short side thereof is substantially parallel to a rolling direction of the rolled metal plate.

According to the electronic component housing package of the present invention, since the short side of the metal frame is punched so as to be at an angle substantially parallel to the rolling direction of the rolled metal plate, The thermal stress applied to the brazing metallization layer when brazing to the brazing metallization layer or when welding the metal lid to the metal frame is reduced. This is because the metal frame manufactured by punching a rolled metal plate has the property that the coefficient of thermal expansion is large in the rolling direction and small in the direction perpendicular to the rolling direction. This is because thermal expansion in the long side direction of the metal frame is suppressed. As a result, the metal frame can be firmly joined to the brazing metallization layer.

[0009]

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

FIG. 1 is a perspective view showing an embodiment of an electronic component storage package according to the present invention, in which 1 is an insulating base, 2 is a metal frame, and 3 is a metal lid. These mainly constitute a container for hermetically containing the electronic component 6.

The insulating base 1 has, for example, a side length of 2 to 20.
It has a substantially rectangular shape having a thickness of about 0.5 mm to about 3 mm, and a substantially rectangular concave mounting portion 1a for mounting the electronic component 6 is provided at the center of the upper surface thereof. The electronic component 6 is mounted and fixed on the mounting portion 1a.

The insulating substrate 1 is made of an electrically insulating material such as a sintered body of aluminum oxide, a sintered body of aluminum nitride, a sintered body of mullite, and a glass-ceramic. If it is, aluminum oxide, silicon oxide, calcium oxide,
Organic binder suitable for raw material powder such as magnesium oxide
A plurality of ceramic green sheets are obtained by adding a solvent and mixing to form a slurry, and forming the sheet into a sheet by employing a conventionally known doctor blade method or the like. Applying appropriate punching and laminating these up and down,
It is manufactured by firing at a temperature of about 1600 ° C.

A plurality of metallized wiring conductors 4 extending from the bottom surface of the mounting portion 1a to the lower surface of the mounting portion 1a via the side surfaces are formed on the insulating substrate 1. Metallized wiring conductor 4
Functions as a conductive path for electrically connecting each electrode of the electronic component 6 mounted on the mounting portion 1a to an external electric circuit, and each electrode of the electronic component 6 is soldered on the bottom surface of the mounting portion 1a. And a portion led out to the lower surface of the insulating base 1 is connected to an external electric circuit through an electrical connection means made of solder or the like. You.

The metallized wiring conductor 4 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. The ceramic green sheet for the base 1 is printed and applied in a predetermined pattern by a screen printing method, and is fired together with the ceramic green sheet laminate for the insulating base 1 to thereby mount the lower surface of the mounting portion 1a of the insulating base 1 from the bottom to the side. Is formed.

Note that the surface of the metallized wiring conductor 4
In order to effectively prevent the metallized wiring conductor 4 from being oxidized and corroded and to improve the connectivity between the metallized wiring conductor 4 and the electrical connection means, usually, nickel having a thickness of about 1 to 10 μm is used. Plating layer and thickness 0.1
A gold plating layer having a thickness of about 3.0 μm is sequentially applied by a conventionally known electrolytic plating method or electroless plating method.

Further, on the upper surface of the insulating base 1, a mounting portion 1 is provided.
A substantially rectangular frame-shaped brazing metallization layer 5 made of metal powder of tungsten, molybdenum, copper, silver or the like is formed so as to surround a. The brazing metallization layer 5 has a thickness of, for example, about 10 to 20 μm and a width of each side of about 0.2 to 0.5 mm, and functions as a base metal for joining the metal frame 2 to the insulating base 1.
On the upper surface of the brazing metallization layer 5, a substantially rectangular frame-shaped metal frame 2 surrounding the mounting portion 1a is brazed via a brazing material such as silver brazing. Such a metallized layer 5 for brazing is formed by adding a suitable organic binder and a solvent to a metal powder such as tungsten and mixing the metal paste to a ceramic green sheet for the insulating substrate 1 in a predetermined pattern by a screen printing method. By printing and applying this and baking it together with the ceramic green sheet laminate for the insulating substrate 1, it is adhered and formed on the upper surface of the insulating substrate 1 so as to surround the mounting portion 1a.

In order to improve the wettability between the brazing metallization layer 5 and the brazing material, the surface of the brazing metallization layer 5 is usually nickel-plated with a thickness of about 0.5 to 5 μm. The layers are pre-applied before brazing.

The metal frame 2 brazed to the brazing metallization layer 5 via a brazing material such as silver brazing is made of a metal such as an iron-nickel alloy or an iron-nickel-cobalt alloy. The lid 3 functions as a base metal member for welding to the insulating base 1. This metal frame 2 usually has an inner circumference substantially the same size as the opening of the mounting portion 1a,
The thickness is about 0.1 to 0.25 mm, and the width of each side is about 0.1 to 0.4 mm. Further, each corner of the outer peripheral surface and the inner peripheral surface has a radius of curvature of about 0.1 to 2 mm. Then, the metal cover 3 is placed on the metal frame 2, and the metal cover 3 is joined to the metal frame 2 by welding them by, for example, a seam welding method.

As shown in the top view of FIG. 2, such a metal frame 2 is formed by rolling a rolled metal plate 20 made of an iron-nickel alloy or an iron-nickel-cobalt alloy, etc. It is manufactured in a predetermined frame shape by punching out at an angle substantially parallel to the direction. The brazing of the metal frame 2 to the brazing metallization layer 5 is as follows.
The metal frame 2 is placed on the brazing metallizing layer 5 with a foil-like brazing material having a thickness of, for example, 10 to 50 μm therebetween, and then the brazing metallizing layer 5 is heated and melted. And the metal frame 2 are brazed. The brazing metallization layer 5 after brazing
In order to effectively prevent the metallized layer 5 for brazing, the metal frame 2 and the brazing material from being oxidized and corroded, the exposed surface of the metal frame 2 and the exposed surface of the brazing material are usually A nickel plating layer having a thickness of 0.5 to 5 [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.

In the present invention, it is important that the short side of the metal frame 2 is punched so as to have an angle substantially parallel to the rolling direction of the rolled metal plate 20. As described above, since the short side of the metal frame 2 is punched so as to be at an angle substantially parallel to the rolling direction of the rolled metal plate 20, the thermal expansion coefficient of the long side of the metal frame 2 is reduced. Become smaller. This is because the coefficient of thermal expansion of the rolled metal plate 20 in the rolling direction is larger than the coefficient of thermal expansion in the direction orthogonal to the rolling direction. The thermal stress generated by the thermal expansion of the metal frame 2 is
The longer the length of each side is, the larger the thermal expansion coefficient of the long side is. Therefore, when the metal frame 2 is brazed to the metallizing layer 5 for brazing or when the metal Thermal stress applied to the brazing metallization layer 5 when the body 3 is welded can be reduced. As a result, according to the electronic component storage package of the present invention, the metallized layer 5 is not peeled off from the insulating base 1 even when the metal lid 3 is welded to the metal frame 2 by the seam welding method. An excellent package for storing electronic components can be provided.

Thus, according to the electronic component housing package of the present invention, the electronic component 6 is mounted and fixed on the mounting portion 1a of the insulating base 1 such that each electrode is electrically connected to the metallized wiring conductor 4. Thereafter, the metal lid 3 is welded to the metal frame 2 brazed to the insulating base 1 by a seam welding method or the like, and the electronic component 6 is hermetically sealed therein to obtain an electronic device.

It should be noted that the present invention is not limited to the above-described embodiment, and it is needless to say that various modifications can be made without departing from the scope of the present invention.

[0023]

According to the electronic component housing package of the present invention, since the short side of the metal frame is punched at an angle substantially parallel to the rolling direction of the rolled metal plate,
The coefficient of thermal expansion on the long side of the metal frame is reduced. As a result, when the metal frame is brazed to the metallization layer for brazing or when the metal lid is welded to the metal frame, the metallization layer for brazing is used. Can be reduced. Therefore, it is possible to provide an electronic component housing package having excellent hermetic reliability in which the brazing metallization layer does not peel off from the insulating substrate even when the metal lid is welded to the metal frame by the seam welding method.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an example of an embodiment of an electronic component storage package according to the present invention.

FIG. 2 is a top view for explaining a method of manufacturing the metal frame 2 of the electronic component storage package shown in FIG.

FIG. 3 is a perspective view showing a conventional electronic component storage package.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Insulating base 1a ... Mounting part 2 ... Metal frame 3 ... Metal cover 5 ... Metallized layer for brazing 6 ... Electronic components 20 ...・ Rolled metal sheet

Claims (1)

[Claims] 1. A rolled metal plate is punched into a brazing metallization layer of an insulating substrate having a mounting portion on which an electronic component is mounted on an upper surface and a substantially rectangular frame-shaped brazing metallization layer surrounding the mounting portion. It is formed by attaching the formed substantially rectangular frame-shaped metal frame so as to surround the mounting portion,
In the electronic component housing package in which a metal lid is joined to the metal frame, the metal frame is punched such that a short side thereof is substantially parallel to a rolling direction of the rolled metal plate. An electronic component storage package that has been removed.