JP2003046017A - Electronic component housing package and manufacturing method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic component housing package, having high reliability by ensuring sufficient airtightness at the part joined to a base part, even if the package is miniaturized and the width of a frame part is made smaller. SOLUTION: In the electronic component housing package, consisting of an insulating substrate 1, formed of a base part 1a having a mounting part 5 for an electronic component 3 and a frame part 1b joined to the upper surface of the base part 1a to surround the mounting part 5, and a cover 2 mounted on the frame part 1b, the frame part 1b is pressed at the underside thereof, into the base part 1a to be joined thereto. Even if the width of the frame part is made narrower, the electronic component housing package 4, having high reliability, can be provided because the lamination property of the base part 1a and the frame part 1b is improved and the airtightness of the junction is ensured.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a package for housing electronic parts such as a semiconductor device and a crystal oscillator, which has excellent airtightness and reliability, and a manufacturing method thereof.

[0002]

2. Description of the Related Art Conventionally, electronic component storage packages for storing electronic components are generally made of aluminum oxide sintered material, mullite sintered material, aluminum nitride sintered material, glass ceramic sintered material, or the like. An insulating base body made of an insulating material and comprising a plate-shaped base portion having a mounting portion for mounting an electronic component on an upper surface thereof, and a frame portion joined to the upper surface of the base portion so as to surround the mounting portion of the electronic component. , A wiring conductor made of metal powder of tungsten, molybdenum, manganese, copper, silver, etc., which is adhered and led from the inside to the outside of the frame portion of the insulating base, and a lid body attached to the upper surface of the frame portion. Has been done,
The electronic component is adhered and fixed to the base portion of the insulating substrate via an adhesive such as glass, resin, or brazing material, and each electrode of the electronic component is electrically connected to a wiring conductor through, for example, a bonding wire. After that, the lid is joined to the upper surface of the frame portion of the insulating base through the sealing material made of glass, resin, brazing material, etc., and the electronic parts are hermetically housed inside the container made of the insulating base and the lid. Becomes an electronic device.

The insulating substrate of such a package for storing electronic parts is usually manufactured by stacking green sheets and firing them. That is, a step of preparing a plate-shaped first green sheet to be a base portion, a step of preparing a second green sheet to be a frame portion having a shape surrounding an area to be a mounting portion of the base portion, The second green sheet is laminated on the upper surface of the first green sheet to obtain a laminated body, and the laminated body is fired to obtain an insulating substrate in which the upper surface of the base portion is joined to the lower surface of the frame portion. It

In this case, since the first and second green sheets have almost the same hardness, the interface between the first green sheet and the second green sheet, that is, the joint surface between the base portion and the frame portion is The same surface as the upper surface of the first green sheet is substantially flat, and the base portion and the frame portion are laminated in parallel and in layers.

[0005]

However, in recent years,
With the miniaturization of components, the width of the frame portion of this electronic component storage package is becoming narrower. Therefore, the joint area between the base portion and the frame portion decreases, and the airtightness at the joint surface between the base portion and the frame portion tends to decrease. As described above, the conventional electronic component storage package has a problem that it is difficult to reduce the size while maintaining the airtightness.

The present invention has been devised in view of the above-mentioned problems of the prior art, and an object thereof is to achieve high airtight reliability even if the package for storing electronic parts is made small and the width of the frame portion becomes narrow. The object is to provide a compact, highly reliable package for storing electronic components, which has high performance.

[0007]

An electronic component storing package of the present invention is a plate-shaped base portion having a mounting portion for electronic components and a frame joined to the upper surface of the base portion so as to surround the mounting portion. In an electronic component storage package including an insulating base formed of a portion and a lid joined to the upper surface of the frame portion, the frame portion is joined by pushing the lower surface of the frame portion into the upper surface of the base portion. It is characterized by being present. Further, the electronic component storage package of the present invention is characterized in that, in the above structure, the depth of the lower surface of the frame portion pressed into the upper surface of the base portion is 15 μm to 25 μm.

Further, the electronic component storing package of the present invention is characterized in that, in the above structure, the lower surface of the frame portion is steppedly pushed into the upper surface of the base portion inside the frame portion. Is.

Further, in the package for storing electronic parts of the present invention, in the above structure, the surface roughness of the lower surface of the frame portion and the upper surface of the base portion is 1.6 μm to 2.8 μm in terms of center line average roughness (Ra). It is characterized by being.

In the method of manufacturing a package for storing electronic components of the present invention, the step of preparing a plate-shaped first green sheet that serves as a base portion and the first green sheet that serves as a frame-shaped frame portion are used. A step of preparing a hard second green sheet, and stacking the second green sheet on the upper surface of the first green sheet and press-bonding the second green sheet to the upper surface of the first green sheet and the lower surface of the second green sheet. And a step of obtaining a laminated body by pressing the lower surface of the frame portion onto the upper surface of the base portion and firing the laminated body. .

According to the electronic component storing package of the present invention, the lower surface of the frame portion joined to the upper surface of the base portion of the insulating base so as to surround the mounting portion of the electronic component is pushed into the upper surface of the base portion to be joined. Therefore, even if the package is downsized and the width of the frame portion is narrowed, the joint area between the frame portion and the base portion can be increased and a step can be formed on this joint surface. Good airtightness can be ensured at the joint surface between the frame part and the frame part. As a result, it is possible to reduce the size of the package while maintaining good airtightness.

When the depth at which the lower surface of the frame portion is pressed into the upper surface of the base portion is set to 15 μm to 25 μm, good airtightness can be obtained at the joint surface and deformation is caused at the mounting portion of the base portion. It is preferable for mounting electronic parts with high accuracy without causing the problem.

Further, when the lower surface of the frame portion is pushed into the upper surface of the base portion inside the frame portion in a stepwise manner, when the insulating substrate is contracted by firing, the mounting portion of the electronic component of the base portion is removed. Since the frame portion pressed in the surrounding shape contracts in the direction of tightening the base portion, the adhesion of the portion where the base portion and the frame portion are in contact with each other at the step surface perpendicular to the laminated surface is improved, It is possible to more reliably prevent the occurrence of local stacking failure that causes airtightness failure, and it is possible to obtain good airtightness reliability.

The surface roughness of the lower surface of the frame portion and the upper surface of the base portion is 1.6 in terms of center line average roughness (Ra).
When the thickness is from μm to 2.8 μm, the joint surface between the lower surface of the frame portion and the upper surface of the base portion can be appropriately roughened to effectively generate the anchor effect and to perform favorable joining, which is even more reliable. Airtightness can be obtained.

Further, according to the method of manufacturing a package for storing electronic parts of the present invention, a step of preparing a plate-shaped first green sheet which becomes a base portion, and the first green which becomes a frame-shaped frame portion A step of preparing a second green sheet that is harder than a sheet, and stacking the second green sheet on the upper surface of the first green sheet and press-bonding the second green sheet to the second green sheet on the upper surface of the first green sheet. The step of obtaining a laminated body in which the lower surface of the frame is pressed, and the step of firing the laminated body to press the lower surface of the frame portion into the upper surface of the base portion to obtain the joined insulating base, It is possible to reliably and efficiently manufacture the electronic component storing package of the present invention, which is composed of the insulating base body and the lid body which are joined by pushing the lower surface thereof onto the upper surface of the base portion. Kill.

[0016]

DETAILED DESCRIPTION OF THE INVENTION The present invention will now 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, wherein 1 is an insulating substrate and 2 is a lid. The insulating base 1 and the lid 2 constitute an electronic component storage package 4 for storing the electronic component 3.

The insulating substrate 1 has a plate-like base portion 1a having a mounting portion 5 on which an electronic component is mounted at a substantially central portion of the upper surface.
And a frame portion 1b which is laminated and joined to the upper surface of the base portion 1a so as to surround the mounting portion 5. The base portion 1a and the frame portion 1b are made of a glass ceramics sintered body, an aluminum oxide sintered body, a mullite sintered body, a silicon nitride sintered body, an aluminum nitride sintered body, etc. It is formed by the material.

The electronic component 3 is adhered and fixed to the mounting portion 5 on the upper surface of the base portion 1a via an adhesive material 6 such as resin, glass, or a brazing material. When a brazing material is used as the adhesive material 6, the metallized layer 7 is usually formed on the mounting portion 5 on the upper surface of the base portion 1a.

A wiring conductor 8 is formed on the insulating base 1 so as to extend from the periphery of the mounting portion 5 of the base portion 1a to the outer surface, for example, the outer periphery of the lower surface, and the mounting portion of the wiring conductor 8 is formed. Around 5 (inside the frame part 1b)
The electrodes of the electronic component 3 are electrically connected to the exposed portions through the bonding wires 9, and the insulating substrate 1
The parts led out to the outer peripheral portion of the lower surface of the are connected to the external connection electrodes 10 respectively, and through a brazing material such as solder to the mounting conductor layer to which the circuit wiring of the external electric circuit board (not shown) is connected. It is electrically connected.

Such a wiring conductor 8 functions as a conductive path when the electronic component 3 is connected to the circuit wiring of the external electric circuit board, and is a metallized layer using a metal powder of copper, silver, tungsten, molybdenum, manganese or the like. Is formed by.

On the exposed surface of the wiring conductor 8, a metal having excellent corrosion resistance such as nickel or gold and having excellent wire bonding property and wettability of brazing material is applied to a thickness of 1 μm to 20 μm by a plating method. If this is done, oxidative corrosion of the wiring conductor 8 can be effectively prevented and the bonding wire 9 can be firmly joined to the wiring conductor 8, and a brazing material for the external electric circuit board of the electronic component housing package 4 can be obtained. It is possible to further secure the joining via the. Therefore, it is preferable that the exposed surface of the wiring conductor 8 is coated with a metal having excellent corrosion resistance such as nickel and gold and excellent bonding property and wettability of the brazing material in a thickness of 1 μm to 20 μm.

In the present invention, it is important that the frame portion 1b is joined by pushing its lower surface into the upper surface of the base portion 1a. By pushing the lower surface of the frame portion 1b onto the upper surface of the base portion 1a, the joint area between the base portion 1a and the frame portion 1b can be increased, and at the same time the base portion 1a and the frame portion 1b are formed inside the frame portion 1b. A step can be generated in the contacting portion of the two, and the connection can be made more firmly.

When a step is formed on the joint surface between the base portion 1a and the frame portion 1b, the frame portion 1b is contracted by the firing due to the shrinkage of the frame portion 1b with respect to the base portion 1a in the firing step in the process of manufacturing the insulating substrate 1 described later. , The contact surface of the step in the direction perpendicular to the laminated surface is tightened by the effect similar to the so-called "caulking" so that the close contact is achieved, so that a strong adhesion can be obtained. In this way, since the bonding area is increased and the strong adhesiveness is obtained at the step portion, the frame portion 1b is firmly and firmly bonded to the base portion 1a even if the insulating substrate 1 is downsized. Therefore, it is possible to ensure the airtightness of the package, and it is possible to suppress the occurrence of the airtightness failure due to the stacking failure observed on the stacking boundary surface.

The pushing depth Lc of the lower surface of the frame portion 1b to the upper surface of the base portion 1a is 15 μm to 25 μm.
Is desirable. If it is less than 15 μm, a sufficient step is not formed, and the effect of significantly improving airtightness tends to be difficult to see. On the other hand, if the thickness exceeds 25 μm, the warp deformation of the mounting surface 5 of the base portion 1a may increase in accordance with the indentation depth Lc, so that a problem may occur in mounting the electronic component 3. Therefore, it is preferable that the indentation depth Lc of the lower surface of the frame portion 1b into the upper surface of the base portion 1a is 15 μm to 25 μm.

Further, the surface roughness of the lower surface of the frame portion 1b and the upper surface of the base portion 1a is defined by the center line average roughness (R
It is desirable that the thickness is 1.6 μm to 2.8 μm in a). When the surface roughness of each is less than 1.6 μm in terms of the center line average roughness (Ra), the adhesiveness between the lower surface of the frame portion 1b and the upper surface of the base portion 1a decreases because the joint surface is flat. It tends to be difficult to ensure proper airtightness. On the other hand, if it exceeds 2.8 μm, a void may be generated between the joint surfaces, and in this case as well, the adhesion between the lower surface of the frame portion 1b and the upper surface of the base portion 1a is reduced, and good airtightness is ensured. Tends to be difficult to do. Therefore, the surface roughness of the lower surface of the frame portion 1b and the upper surface of the base portion 1a is 1.6 μm in terms of center line average roughness (Ra).
To 2.8 μm is preferable.

The frame portion 1b is preferably provided with rounded corners when viewed from above. As a result, when the lid body 2 is joined to the upper surface of the frame portion 1b via, for example, a brazing material, thermal stress concentrates at each corner portion, and the joining reliability of the lid body 2 via the brazing material deteriorates. Can be effectively prevented.

Further, it is preferable that the surface state of the region of the frame portion 1b to which the lid 2 is attached is changed according to the attaching method of the lid 2. For example, when the lid 2 is brazed and joined via a brazing material, it is preferable to form a metal layer of nickel, gold or the like on the surface in order to improve the wettability with the brazing material.

Table 1 shows the insulating substrate 1 under various conditions regarding the width of the frame portion 1b and the indentation depth Lc.
6 shows the results of measuring the airtightness failure occurrence rate and the warp of the bottom surface of the recessed portion which becomes the mounting portion 5 in FIG.

[0030]

[Table 1]

As can be seen from the results of Table 1, all the packages for storing electronic parts of the present invention show a good rate of occurrence of airtightness failure and warpage of the bottom surface of the recess, but in particular, the indentation depth Lc is from 15 μm to It can be seen that when the range is 25 μm, the occurrence rate of airtightness is 0 ppm, which is extremely good airtightness, and the warp of the bottom surface of the recess is 25 μm or less, which is also very good flatness.

The joining in which the lower surface of the frame portion 1b is pushed into the upper surface of the base portion 1a is, for example, at the time of forming the green sheet, the hardness of the green sheet which becomes the base portion 1a as compared with the green sheet which becomes the frame portion 1b. By molding 10% to 15% lower, the base part 1a is deformed when the green sheet that becomes the frame part 1b is laminated and pressure-bonded to the green sheet that becomes the base part 1a, thereby forming an appropriate indentation. Can be joined.

Thus, according to the electronic component storing package 4 of the present invention, the electronic component 3 is adhered and fixed to the upper surface of the base portion 1a of the insulating substrate 1 through the adhesive 6 made of glass, resin, brazing material or the like. Each electrode of the electronic component 3 is connected to a predetermined wiring conductor 8 via a bonding wire 9, and then the lid 2 is mounted on the upper surface of the insulating base 1 via a sealing material made of glass, resin, brazing material or the like. A semiconductor device is obtained by bonding and hermetically housing the electronic component 3 inside the electronic component housing package 4 including the insulating base 1 and the lid 2.

Next, a method of manufacturing the electronic component storing package of the present invention will be described.

2 (a) to 2 (d) are cross-sectional views for explaining the method of manufacturing the electronic component storing package according to the present invention in the order of steps, in which the same parts as those in FIG. 1 are designated by the same reference numerals. Is attached.

First, as shown in FIG. 2A, a plate-shaped first green sheet 11 to be the base portion 1a is prepared.

The first green sheet 11 is suitable as a raw material powder composed of glass powder such as borosilicate glass and ceramic powder such as aluminum oxide when the insulating substrate 1 is composed of a glass ceramic sintered body. While adding and mixing various organic binders and solvents to make sludge,
The sludge is formed into a sheet by adopting a doctor blade method or a calendar roll method, and is also formed into a predetermined plate by subjecting it to appropriate punching.

Next, as shown in FIG. 2 (b), a second green sheet 12 to be the frame portion 1b is prepared.

The second green sheet 12 is a mounting portion formed on the upper surface of the base portion 1a by appropriately punching a sheet-shaped molded body obtained by using the same material as that of the first green sheet 11. It is formed by molding into a frame shape surrounding 5.

The second green sheet 12 is preferably formed to have a hardness higher than that of the first green sheet 11 by applying a high pressure before the punching process.

In this case, the first green sheet 11 and the second green sheet
The difference in hardness from the green sheet 12 is that the second green sheet 12 is laminated on the upper surface of the first green sheet 11 and pressure-bonded to the second green sheet 11 on the upper surface of the first green sheet 11.
In order to obtain a laminate in which the lower surface of 12 is pressed appropriately,
When a needle having a hemispherical tip and a diameter of 300 μm is pushed in with a force of 980 mN, the difference in penetration depth is preferably a hardness difference in the range of 20 μm to 30 μm. Next, as shown in FIG. 2C, the second green sheet 12 is replaced with the first green sheet 11.
To obtain a laminate 13 in which the lower surface of the second green sheet 12 is pressed into the upper surface of the first green sheet 11 by laminating and press-bonding the upper surface of the first green sheet 11.

At this time, the hardness of the second green sheet 12 is set to be higher than that of the first green sheet 11, so that the second green sheet is pressed by the pressure caused by the pressure bonding.
The lower surface of 12 is pushed into the upper surface of the first green sheet 11 so as to bite into it.

The indentation depth Lc of the second green sheet 12 with respect to the first green sheet 11 is controlled to a predetermined depth by appropriately adjusting the pressure of pressure bonding according to the hardness of each green sheet. be able to.

Further, in this case, the surface roughness of the lower surface of the second green sheet 12 which becomes the frame portion 1b and the upper surface of the first green sheet 11 which becomes the base portion 1a is the center line average roughness (Ra). It is preferably set to 1.6 μm to 2.8 μm.

Table 2 shows the lower surface of the second green sheet 12 which becomes the frame portion 1b and the first green sheet which becomes the base portion 1a.
The airtight defect occurrence rate in the insulating substrate 1 under various conditions for the surface roughness of the upper surface of the green sheet 11 (the value of the center line average roughness (Ra) is shown as the surface roughness of the bonding surface). It shows the measured results.

[0046]

[Table 2]

As can be seen from the results in Table 2, according to the package for storing electronic components of the present invention, the joint between the frame portion 1b and the base portion is made firm during firing which will be described later, and the package for storing electronic components after firing is provided. It is possible to surely obtain good airtightness in the package.

At this time, the surface roughness of the lower surface of the second green sheet 12 serving as the frame portion 1b and the upper surface of the first green sheet 11 serving as the base portion 1a is 1.6 as the center line average roughness (Ra). By setting the thickness to μm to 2.8 μm, an anchor effect can be effectively generated between the lower surface of the second green sheet 12 and the upper surface of the first green sheet, and the bonding is further surely strengthened. be able to.

The surface roughness is the center line average roughness (Ra).
Is 1.6 μm to 2.8 μm, for example, the surface roughness of the lower surface of the second green sheet 12 and the upper surface of the first green sheet 11 is 1.6 μm to 2.8 μm in terms of center line average roughness (Ra). The method of pressing the sheet material, the method of applying a solvent, or the like can be used.

Next, the laminated body 13 is heated to about 1000 in a reducing atmosphere.
By firing at a temperature of ° C, as shown in Fig. 2 (d), the insulating substrate 1 of the package 4 for storing electronic components of the present invention, in which the lower surface of the frame portion 1a is pressed into the upper surface of the base portion 1b and joined To get

When the lid 2 is made of a metal such as an iron-nickel-cobalt alloy or an iron-nickel alloy, or a ceramic such as an aluminum oxide sintered body, for example, an iron-nickel-cobalt alloy. Then iron-
It is formed by subjecting a nickel-cobalt alloy ingot (lump) to well-known metal working such as rolling and punching.

The present invention is not limited to the examples described in the embodiments of the present invention, and various modifications can be made without departing from the scope of the present invention. For example, the base portion 1a and / or the frame portion 1b
May be formed by stacking a plurality of green sheets, respectively.

[0053]

According to the electronic component storing package of the present invention, the lower surface of the frame portion joined to the upper surface of the base portion of the insulating base so as to surround the mounting portion of the electronic component is pushed into the upper surface of the base portion. Since the package is miniaturized and the width of the frame portion is narrowed, the joint area between the frame portion and the base portion can be increased and a step can be formed on this joint surface. Good airtightness can be secured at the joint surface between the base portion and the frame portion. as a result,
It is possible to reduce the size of the package while maintaining good airtightness.

If the depth at which the lower surface of the frame portion is pressed into the upper surface of the base portion is set to 15 μm to 25 μm, good airtightness can be obtained at the joint surface and deformation at the mounting portion of the base portion is possible. It is preferable for mounting electronic parts with high accuracy without causing the problem.

In addition, when the lower surface of the frame portion is pushed stepwise into the upper surface of the base portion inside the frame portion, when the insulating base is contracted by firing, the mounting portion of the electronic component of the base portion is removed. Since the frame portion pressed in the surrounding shape contracts in the direction of tightening the base portion, the adhesion of the portion where the base portion and the frame portion are in contact with each other at the step surface perpendicular to the laminated surface is improved, It is possible to more reliably prevent the occurrence of local stacking failure that causes airtightness failure, and it is possible to obtain good airtightness reliability.

The surface roughness of the lower surface of the frame portion and the upper surface of the base portion is 1.6 as the center line average roughness (Ra).
When the thickness is from μm to 2.8 μm, the joint surface between the lower surface of the frame portion and the upper surface of the base portion can be appropriately roughened to effectively produce the anchor effect and achieve good joint, and thus the joint surface can be more surely secured. Good airtightness can be obtained.

Further, according to the method of manufacturing the electronic component storing package of the present invention, the step of preparing the plate-shaped first green sheet which becomes the base portion, and the first green which becomes the frame-shaped frame portion A step of preparing a second green sheet that is harder than a sheet, and stacking the second green sheet on the upper surface of the first green sheet and press-bonding the second green sheet to the second green sheet on the upper surface of the first green sheet. The step of obtaining a laminated body in which the lower surface of the frame is pressed, and the step of firing the laminated body to press the lower surface of the frame portion into the upper surface of the base portion to obtain the joined insulating base, It is possible to reliably and efficiently manufacture the electronic component storing package of the present invention, which is composed of the insulating base body and the lid body which are joined by pushing the lower surface thereof onto the upper surface of the base portion. Kill.

[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.

2A to 2D are cross-sectional views illustrating a method of manufacturing an electronic component storing package according to the present invention in the order of steps.

[Explanation of symbols]

1 ... Insulating substrate 1a ... Base part 1b ... Frame part 2 ... Lid 3 ... Electronic components 4 ... Package for storing electronic components 5: Mounting part 11 ... first green sheet 12 ... Second green sheet 13 ... Laminate

Claims (5)

[Claims] 1. A plate-shaped base portion having a mounting portion for an electronic component, an insulating base formed from a frame portion joined to an upper surface of the base portion so as to surround the mounting portion, and an upper surface of the frame portion. An electronic component storing package comprising a lid body attached to the electronic component storing body, wherein the frame portion is joined by pushing the lower surface of the frame portion into the upper surface of the base portion. 2. The package for storing electronic parts according to claim 1, wherein the depth of the lower surface of the frame portion pressed into the upper surface of the base portion is 15 μm to 25 μm. 3. The package for storing electronic components according to claim 1, wherein the lower surface of the frame portion is stepped into the upper surface of the base portion inside the frame portion. 4. The surface roughness of the lower surface of the frame portion and the upper surface of the base portion is 1.6 μm to 2.8 μm in center line average roughness (Ra). Package for storing electronic components. 5. A step of preparing a plate-shaped first green sheet to be a base portion, and a step of preparing a second green sheet harder than the first green sheet to be a frame-shaped frame portion, Stacking the second green sheet on the upper surface of the first green sheet and press-bonding it to obtain a stacked body in which the lower surface of the second green sheet is pressed into the upper surface of the first green sheet; And a step of firing the laminated body to press the lower surface of the frame portion into the upper surface of the base portion to obtain an joined insulating base body.