JP3164798B2 - Electronic equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic device in which electronic components such as a piezoelectric vibrator and a semiconductor element are hermetically housed in a container formed of an insulating base such as ceramics and a metal cover. .

[0002]

2. Description of the Related Art Electronic components such as a piezoelectric vibrator and a semiconductor element are air-tightly accommodated in a container for accommodating the electronic components to become an electronic device as a product.

[0003] Among the electronic devices, the most reliable one is an insulating base made of ceramics such as an aluminum oxide sintered body and having a mounting portion for mounting electronic components at the center of the upper surface. A metal frame made of an iron-nickel alloy or an iron-nickel-cobalt alloy attached to the upper surface of the base so as to surround the mounting portion; and an iron-nickel alloy or iron joined to the metal frame by seam welding. -An electronic component is hermetically sealed inside a container composed of a metal cover made of a nickel-cobalt alloy.

In an electronic device of this type, after mounting an electronic component on a mounting portion of an insulating base, a metal lid is mounted on a metal frame attached to the insulating base, and an outer peripheral edge of the metal lid is mounted. The roller is rolled while a pair of roller electrodes of a seam welding machine are brought into contact with each other, a large current for welding is passed between the roller electrodes, and a metal lid is seam-welded to a metal frame.

In this type of electronic device,
Normally, a nickel plating film and a gold plating film are previously applied to the surfaces of the metal frame and the metal lid, and a part of the nickel plating film and the gold plating film is melted by the heat of seam welding. The frame and the metal lid are welded.

However, in this type of electronic device, it is necessary to melt the nickel plating film and the gold plating film adhered to the metal frame and the metal cover when the metal cover is seam-welded to the metal frame. Therefore, about
High temperatures exceeding 1000 ° C are applied. About 1000 ℃ like this
Is applied to the welded portion, a high thermal shock is transmitted to the insulating substrate as a large thermal shock. As a result, there is a problem that the large thermal shock easily causes cracks in the insulating substrate.

Therefore, when seam welding the metal frame and the metal lid, the melting point between the metal frame and the metal lid is about 800 ° C.
An electronic device welded with the following brazing material interposed has been proposed. According to this electronic device, the metal frame and the metal lid are joined by melting a brazing material having a melting point of about 800 ° C. or less interposed between the metal frame and the metal lid during seam welding. Therefore, it is not necessary to apply a high temperature exceeding 1000 ° C. to the welded portion. Therefore, a large thermal shock is not applied to the insulating base when the metal lid is seam-welded to the metal frame, and it is possible to effectively prevent the occurrence of cracks in the insulating base.

[0008]

However, an electronic component of a type in which electronic components are hermetically housed in a container in which the metal frame and the metal lid are joined by seam welding with a brazing material interposed therebetween. In the apparatus, when seam welding is performed between a metal frame and a metal lid via a brazing material therebetween, a part of the brazing material melted by the heat of seam welding flows out or scatters inside the container. In this way, if a part of the brazing material melted by the heat of seam welding flows out or scatters inside the container, the brazing material joining the metal frame and the metal lid becomes insufficient, and as a result, In addition, a sufficient brazing material pool cannot be formed between the metal frame and the metal lid, and the bonding strength between the metal frame and the metal lid becomes weak. When a stress due to heat or the like generated when the electronic component operates or a stress due to an external impact is applied thereto, the metal lid is peeled off from the metal frame by such stress, and the container is closed. The airtightness has been broken,
There has been a problem that the electronic components housed therein cannot be operated normally and stably for a long period of time.

The present invention has been devised in view of the above problems, and an object of the present invention is to form a sufficient brazing material reservoir at a joint portion of a metal lid and to firmly join the metal lid. Accordingly, it is an object of the present invention to provide an electronic device that can normally and stably operate electronic components housed therein for a long period of time.

[0010]

According to an electronic device of the present invention, an electronic component is mounted inside a metal frame attached to an upper surface of an insulating base and a brazing material is interposed on the upper surface of the metal frame. An electronic device in which a metal lid is joined by seam welding, wherein an inner peripheral edge of a molten region of the brazing material by the seam welding is separated from an inner peripheral edge of the metal frame by 0.05 mm or more, and An outer peripheral portion of the metal lid body is bent downward at a portion corresponding to the melting region, and a brazing material pool is formed between a side surface thereof and an upper surface of the metal frame body.

In the electronic device of the present invention, an electronic component is mounted inside a frame-shaped metallized metal layer adhered to an upper surface of an insulating base, and a seam is formed on the upper surface of the metallized metal layer via a brazing material. An electronic device comprising a metal lid joined by welding, wherein an inner peripheral edge of a fusion region of the brazing material by the seam welding is separated from an inner peripheral edge of the metallized metal layer by 0.05 mm or more, and the metal An outer peripheral portion of the lid body is bent downward at a portion corresponding to the melting region, and a brazing material pool is formed between a side surface thereof and an upper surface of the metallized metal layer.

According to the electronic device of the present invention, the inner peripheral edge of the molten region of the brazing material is separated from the inner peripheral edge of the metal frame or the metallized metal layer by 0.05 mm or more. When seam welding is performed between the attached metal frame and the metallized metal layer of the insulating substrate via a brazing material, a part of the brazing material melted by the heat of the seam welding will try to flow into the container or scatter. However, the flow-out and splashing are effectively prevented by the unmelted brazing material on the inner peripheral edge side of the metal frame or the metallized metal layer, and the outer peripheral portion of the metal lid is formed at a portion corresponding to the melting width of the brazing material. Is bent downward, so that the brazing material between the outer peripheral portion of the metal lid body bent downward and the metal frame or the metallized metal layer is pushed outward, and the side surface of the metal lid body and the metal frame body are bent. Or top surface of metallized metal layer And a large pool of brazing material is formed between them, and the pooling of the brazing material increases the bonding strength of the metal lid.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an electronic device according to the present invention will be described with reference to the accompanying drawings.

FIG. 1 is a sectional view showing an example of an embodiment of an electronic device of the present invention. In the figure, 1 is an insulating base, 2 is a metal frame attached to the insulating base 1, 3 is a metal lid, and 4 is an electronic component such as a piezoelectric vibrator or a semiconductor element. The electronic device is configured by hermetically housing the electronic component 4 in a container including the insulating base 1 to which the metal frame 2 is attached and the metal lid 3.

The insulating substrate 1 functions as a support for supporting the electronic component 4 and is made of a ceramic such as an aluminum oxide sintered body or an aluminum nitride sintered body. 4 has a recess A for accommodating the same. The bottom surface of the concave portion A forms a mounting portion 1a for mounting the electronic component 4, and the electronic component 4 is mounted on the mounting portion 1a.

If the insulating substrate 1 is made of, for example, an aluminum oxide sintered body, an appropriate organic binder and a solvent are added to a raw material powder of aluminum oxide, silicon oxide, magnesium oxide, calcium oxide, etc., and the mixture is mixed. The ceramic green sheet is formed by adopting a doctor blade method or a calender roll method, which is well known in the art, and thereafter, a plurality of ceramic green sheets are subjected to appropriate punching and laminated at a high temperature. It is manufactured by firing.

Further, a metallized wiring layer 5 made of metal powder of metal such as tungsten or molybdenum which is led out from the upper surface of the mounting portion 1a to the lower surface of the insulating substrate 1 is formed on the insulating substrate 1.

The metallized wiring layer 5 functions as a conductive path for electrically leading each electrode of the electronic component 4 to the outside. It is electrically connected via the agent.
The portion of the metallized wiring layer 5 extending to the lower surface of the insulating base 1 is electrically connected to a wiring conductor of an external electric circuit board (not shown) via, for example, solder.

If the metallized wiring layer 5 is made of, for example, metallized tungsten powder, a tungsten paste obtained by adding and mixing an appropriate organic binder and solvent to the tungsten powder is conventionally known on a ceramic green sheet to be used as the insulating substrate 1. Is printed and applied in a predetermined pattern by the screen printing method described above, and is fired together with the ceramic green sheet to be the insulating base 1, so that the insulating base 1 is attached and derived in a predetermined pattern from the upper surface to the lower surface of the mounting portion 1a.

The metallized wiring layer 5 is preferably provided with a metal having excellent corrosion resistance such as nickel and gold and excellent wettability with solder to a thickness of 1 to 20 μm by plating on the exposed surface. In addition, oxidation corrosion of the metallized wiring layer 5 can be effectively prevented, and the connection between the metallized wiring layer 5 and the wiring conductor of the external electric circuit board can be made strong. Therefore, it is preferable that a metal having excellent corrosion resistance, such as nickel and gold, and having excellent wettability with solder is applied to the surface of the metallized wiring layer 5 to a thickness of 1 to 20 μm by plating.

Further, a frame-shaped metallized metal layer 6 having a width of about 0.3 to 0.5 mm and a thickness of about 10 to 50 μm is attached to the outer peripheral portion of the upper surface of the insulating base 1 so as to surround the mounting portion 1a. Is formed. The metal frame 2 is attached to the metallized metal layer 6 via a brazing material 7 such as silver-copper brazing.

The metallized metal layer 6 functions as a base metal for joining the metal frame 2 to the insulating base 1 and is made of a metal powder such as tungsten or molybdenum. For example, in the case of a metallized tungsten powder, a tungsten paste obtained by adding and mixing an appropriate organic binder and solvent to the tungsten powder is used as the insulating substrate 1.
The ceramic green sheet to be formed is applied and printed in a predetermined thickness and a predetermined pattern in advance by using a conventionally known screen printing method, and is fired together with the ceramic green sheet to be the insulating base 1 to be mounted on the upper surface of the insulating base 1 It is formed in a frame shape so as to surround the portion 1a.

When the metallized metal layer 6 is coated with a metal having excellent corrosion resistance, such as nickel and gold, and excellent wettability with the brazing material 7 to a thickness of 1 to 20 μm by plating, The metallized metal layer 6 can be effectively prevented from being oxidized and corroded, and the metal frame 2 can be firmly attached to the metallized metal layer 6 via the brazing material 7. Therefore, on the surface of the metallized metal layer 6, a metal having excellent corrosion resistance, such as nickel or gold, and having excellent wettability with the brazing material 7 is applied to the surface by 1 to 20 μm by plating.
It is preferable to adhere to a thickness of.

The metal frame 2 attached to the metallized metal layer 6 is made of a metal such as an iron-nickel alloy or an iron-nickel-cobalt alloy.
The thickness is about 0.5 mm and the thickness is about 0.2 to 0.5 mm.

The metal frame 2 functions as a base metal member for welding the metal cover 3 to the insulating base 1. The metal cover 3 is seam-welded to the upper surface thereof with a brazing material 8 interposed therebetween. I have.

The metal frame 2 is preferably provided with a metal having excellent corrosion resistance, such as nickel or gold, and excellent wettability with the brazing material 8 on its surface to a thickness of 1 to 20 μm by plating. In addition, the metal frame 2 can be effectively prevented from being oxidized and corroded, and the seam welding of the metal lid 3 to the metal frame 2 via the brazing material 8 can be made strong. Therefore, it is preferable to apply a metal having excellent corrosion resistance, such as nickel or gold, and excellent wettability with the brazing material 8 to a thickness of 1 to 20 μm on the surface of the metal frame 2 by plating.

The metal lid 3 seam-welded to the metal frame 2 is made of an iron-nickel alloy plate or an iron-nickel-cobalt alloy plate having a thickness of about 0.1 mm, and is attached to the insulating base 1. The electronic component 4 is hermetically sealed with the insulating base 1 by being joined to the metal frame 2 by seam welding with the brazing material 8 interposed therebetween.

The joining of the metal cover 3 and the metal frame 2 by seam welding is performed by disposing a brazing material 8 between the flat metal cover 2 and the metal frame 2 attached to the insulating base 1. After that, a pair of roller electrodes R of the seam welding machine are rolled while being in contact with the outer peripheral edge of the metal lid 3, and a large current for welding is passed between the roller electrodes R,
The contact portion between the roller electrode R and the metal cover 3 is caused to generate Joule heat, and this heat is transmitted to the lower surface of the metal cover 3 so that the brazing material 8 is formed.
Is carried out by melting a part 8a of the metal.

The brazing material 8 disposed between the metal lid 3 and the metal frame 2 is made of silver-copper alloy, gold-tin alloy, lead-tin alloy, aluminum-silicon alloy, copper-zinc alloy.・ Silver
It is made of a copper-phosphorus alloy or a silver-indium-tin alloy and functions as a joining material for joining the metal lid 3 to the metal frame 2, and is provided at a contact portion between the outer peripheral edge of the metal lid 3 and the roller electrode. When the heat generated by the generated Joule heat is transmitted to the outer peripheral portion of the lower surface of the metal lid 3, a part 8a of the metal lid 3 is melted with a melting region corresponding to the heat.

When the brazing material 8 is disposed between the metal lid 3 and the metal frame 2, the lower surface of the metal lid 3 is clad in advance in order to improve the workability of the arrangement. And a thickness of about 10 to 50 μm by plating or the like.

In the electronic device of the present invention, the inner peripheral edge of the molten region W1 of the brazing material 8a from the outer peripheral edge of the metal cover 3 to the inner side at this time is 0.05 m from the inner peripheral edge of the metal frame 2.
m or more, and the melting region W of the brazing material 8a
It is important to bend the outer peripheral portion of the metal lid 3 downward at the portion corresponding to 1 as indicated by K at the bent portion of the metal lid 3 in FIG.

The brazing material 8 extends from the outer peripheral edge of the metal lid 3 to the inside.
a with respect to the inner peripheral edge of the metal frame 2
When the metal cover 3 is seam-welded to the metal frame 2 via the brazing material 8 by being separated by 0.05 mm or more, a part of the molten brazing material 8a is in the concave portion 1a of the insulating base 1. Even if an attempt is made to flow out or scatter, the flow out or scatter is effectively prevented by the unmelted brazing material 8 inside the molten brazing material 8a serving as a barrier. At this time, by bending the outer peripheral portion of the metal cover 3 corresponding to the melting region W1 of the brazing material 8a downward, the outer peripheral portion (bent portion K) of the bent metal cover 3 and the metal frame 2 are bent. The molten brazing material 8a is extruded outward to form a large brazing material reservoir between the side surface of the metal lid 3 and the upper surface of the metal frame 2, whereby the metal lid 3 is 2 is very strongly bonded.

In order to make the inner peripheral edge of the molten region W1 of the brazing material 8a away from the inner peripheral edge of the metal frame 2 by 0.05 mm or more, a roller electrode of a seam welding machine is mounted on the outer peripheral edge of the metal lid 3. When the roller is rolled while being in contact with it and a current for seam welding is passed between the roller electrodes R, the magnitude of the current flowing between the roller electrodes R and the rolling speed of the roller electrode R are controlled when seam welding is performed. It may be adjusted to an appropriate value according to the type of the material 8 and the facing width W2 between the metal lid 3 and the metal frame 2. Further, in order to bend the outer peripheral portion of the metal cover 2 corresponding to the melting region W1 of the brazing material 8a downward,
At the time of this seam welding, seam welding may be performed while applying a load sufficient to bend the metal cover 3 to the outer peripheral edge of the metal cover 3 from above via the roller electrode R. At this time,
The metal lid 3 is supported by the unmelted brazing material 8 at the inner portion where the brazing material 8 is not melted and cannot be pushed down, but is not melted at the outer peripheral portion corresponding to the molten brazing material 8a. Since this portion is pushed down by the thickness of the material 8, this portion is bent downward to form a bent portion K, and a part of the melted brazing material 8a is pushed out, and the side surface of the metal cover 3 and the metal frame A large brazing material pool is formed between the upper surface of the body 2.

When the inner peripheral edge of the molten region W1 of the brazing material 8a inside from the outer peripheral edge of the metal lid 3 is closer than 0.05 mm to the inner peripheral edge of the metal frame 2, the brazing material 8a melted during seam welding is formed. Is exposed in the concave portion 1a of the insulating base 1 and flows out or scatters, so that the brazing material for joining the metal frame 2 and the metal lid 3 becomes insufficient, and the brazing material 8 that is not melted As a result, the outer peripheral portion of the metal lid 3 cannot be bent downward because of the inability to support the metal lid 3, so that there is a sufficient brazing material pool between the metal frame 2 and the metal lid 3. Is difficult to form. Therefore, the inner peripheral edge of the molten region W1 of the brazing material 8a needs to be separated from the inner peripheral edge of the metal frame 2 by 0.05 mm or more.

Thus, according to the electronic device of the present invention, the normal operation of the electronic component 4 is prevented in the interior of the container including the insulating base 1 with the metal frame 2 attached thereto and the metal lid 3. Thus, an electronic device housed with high airtightness can be obtained.

The present invention is not limited to the above-described embodiment, and it goes without saying that various changes can be made without departing from the scope of the present invention.

For example, in the above-described embodiment, the metal cover 3 is seam-welded to the metal frame 2 attached to the insulating base 1, but the metal cover 3 is not necessarily connected to the metal frame 2. It is not necessary to be joined to the insulating base 1 through the intermediary. For example, as shown in the sectional view of FIG. 2, the metal cover 3 is directly seam-welded to the metallized metal layer 6 via the brazing material 8 without attaching the metal frame 2 to the metallized metal layer 6 of the insulating base 1. May be. In this case, the inner peripheral edge of the molten region W1 of the brazing material 8a is separated from the inner peripheral edge of the metallized metal layer 6 by 0.05 mm or more, and the outer peripheral portion of the metal lid 3 corresponding to the molten region W1 is bent downward. Similarly, the bent portion K may be used.

[0038]

According to the electronic device of the present invention, since the inner peripheral edge of the molten region of the brazing material is separated from the inner peripheral edge of the metal lid and the metal frame or the metalized metal layer by 0.05 mm or more,
When the metal lid is seam-welded between the metal frame attached to the insulating base and the metallized metal layer of the insulating base via the brazing material, a part of the brazing material melted by the heat of the seam welding enters the container. Even if you try to spill or try to scatter, the spill or splatter is effectively prevented by the unmelted brazing material inside, and the outer periphery of the metal lid is lowered downward at the position corresponding to the melting region of the brazing material. A brazing material pool is formed between the side surface of the bent metal cover and the upper surface of the metal frame or the metallized metal layer. The brazing material is extruded outward to form a large brazing material pool between the side of the metal lid and the upper surface of the metal frame or metallized metal layer. Contact to metal layer It shall intensity is high, the electronic components accommodated therein as a complete hermetic sealing of the container for a long period of time can be operated normally and stably for a long period of time.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating an example of an embodiment of an electronic device of the present invention.

FIG. 2 is a cross-sectional view showing another example of the embodiment of the electronic device of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Insulating base 1a ... Mounting part 2 ... Metal frame 3 ... Metal cover 4 ... Electronic parts 6 ... Metallized metal layer 8... Brazing material W1... Molten region of brazing material W2... Opposing width between upper surface of metal frame and metal cover W3... Upper surface of metallized metal layer and metal cover Width of the metal lid body

Claims (2)

(57) [Claims] An electronic component is mounted inside a metal frame attached to an upper surface of an insulating base, and a metal lid is joined to the upper surface of the metal frame by seam welding via a brazing material. In the electronic device, an inner peripheral edge of the molten region of the brazing material by the seam welding is separated from the inner peripheral edge of the metal frame by at least 0.05 mm, and an outer peripheral portion of the metal lid is the molten region. A brazing material pool between the side surface thereof and the upper surface of the metal frame by bending downward at a portion corresponding to
An electronic device, wherein: is formed . 2. An electronic component is mounted inside a frame-shaped metallized metal layer attached to an upper surface of an insulating base, and a metal lid is joined to the upper surface of the metalized metal layer by seam welding via a brazing material. An electronic device comprising: an inner peripheral edge of a melting region of the brazing material formed by the seam welding is separated from an inner peripheral edge of the metallized metal layer by 0.05 mm or more; and an outer peripheral portion of the metal lid is In the melting area
At the corresponding part, it is bent downward and its side
An electronic device , wherein a brazing material pool is formed between the brazed metal layer and an upper surface of the metalized metal layer .