JP2000012721A - Container for electronic component - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance reliability of hermetic sealing for a container for housing electronic component. SOLUTION: This container for an electronic component 3 comprises an insulating basic body 1 and a cover 2 bonded through a sealing material 7 where the modulus of elasticity of the sealing member 7 is 5 GPa or less, when the difference of the coefficient of thermal expansion between the insulating basic body 1 and the cover 2 is 2.0×10-6/ deg.C or above.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a container for accommodating electronic components such as surface acoustic wave devices and semiconductor devices.

[0002]

2. Description of the Related Art Conventionally, an electronic component storage container for storing an electronic component, for example, a surface acoustic wave device, is usually made of an electrically insulating material such as an aluminum oxide sintered body, and the surface acoustic wave device is mounted on the upper surface thereof. An insulating base having a plurality of metallized wiring layers made of a refractory metal powder such as tungsten, molybdenum, and manganese having a recess to be accommodated and led out from the bottom to the bottom of the recess, and an iron-nickel-cobalt alloy. And a lid made of a metal material such as iron-nickel alloy. The surface acoustic wave element is bonded and fixed to the bottom surface of the concave portion of the insulating base via an adhesive made of resin, and the electrodes of the surface acoustic wave element are bonded. It is connected to the metallized wiring layer via a wire, and then a metal lid is placed on the upper surface of the insulating base via a sealing member made of a brazing material such as a gold-tin alloy. Engaged thereby, the surface acoustic wave device as a product by housing the surface acoustic wave element to the container interior made of an insulating base and the lid.

[0003] In the above-mentioned conventional electronic component storage container, a metallized metal layer for sealing is previously applied in a frame shape on the upper surface of an insulating base, and a metal lid is provided on the metallized metal layer for sealing. The lid is joined to the insulating base by joining via a sealing member made of a brazing material such as a gold-tin alloy, whereby the surface acoustic wave element is accommodated inside the container consisting of the insulating base and the lid. Becomes

[0004]

However, in this conventional electronic component storage container, the surface acoustic wave element is bonded and fixed to the insulating base via an adhesive made of resin, and is provided on the insulating base. The sealing member for joining the metal lid to the metallized metal layer for sealing is made of a brazing material such as a gold-tin alloy and has a heating and melting temperature of about 30.
Since the temperature is as high as 0 ° C., when joining a metal lid to a metallized metal layer for sealing via a sealing member made of a brazing material such as a gold-tin alloy, heat for heating and melting the sealing member is insulated. When applied to the resin adhesive that adheres and fixes the surface acoustic wave element to the substrate, a gas is generated from the resin adhesive, and the impurities contained in this gas adhere to the electrodes of the surface acoustic wave element, and the characteristics of the surface acoustic wave element The surface acoustic wave element cannot be operated normally, and part of the resin adhesive is decomposed, and the reliability of the adhesive fixation of the surface acoustic wave element is greatly degraded. Was.

In order to solve the above-mentioned drawbacks, it is conceivable that the sealing member is formed of a resin adhesive having a low heat treatment temperature, particularly an epoxy resin which is considered to have good moisture resistance among resins.

However, since this epoxy resin has a high hardness after heat treatment and thermal curing, the difference in thermal expansion coefficient between the insulating base and the metallic lid is 2.0 × 10 ⁻⁶ / ° C. or more. When thermal stress due to the difference in thermal expansion coefficient between the insulating base and the metal lid is repeatedly applied to the sealing member made of epoxy resin, the sealing member peels off from the insulating base or the metal lid, and There is a disadvantage that the reliability of hermetic sealing is greatly degraded and the surface acoustic wave element housed in the container cannot be operated normally and stably for a long period of time. The present invention has been made in view of the above-described drawbacks, and has as its object to increase the reliability of sealing of a container including an insulating base and a metal lid, and to provide an electronic component housed inside the container. An object of the present invention is to provide an electronic component storage container that can be normally and stably operated for a long period of time.

[0007]

According to the present invention, there is provided an electronic device in which an insulating base and a lid are joined via a sealing member, and an electronic component is accommodated in a container including the insulating base and the lid. A container for storing parts, wherein the elastic modulus of the sealing member is 5 GPa or less when the difference between the thermal expansion coefficients of the insulating base and the lid is 2.0 × 10 ⁻⁶ / ° C. or more. Things.

Further, the present invention is characterized in that the sealing member is made of an epoxy resin containing acrylic rubber particles by an external addition in an amount of 5 to 50% by weight.

According to the electronic component storage container of the present invention, the sealing member for joining the insulating base and the lid is made of, for example, 5 to 50 parts by adding acrylic rubber particles to epoxy resin.
%, And the sealing member has an elastic modulus of 5 GPa.
Because of the following moderate flexibility, the difference in thermal expansion coefficient between the insulating base and the metal lid is 2.0 × 10 ⁻⁶ /
° C. or higher, and the sealing member peels from the insulating substrate or the metal lid even if thermal stress caused by the difference in thermal expansion coefficient between the insulating substrate and the metal lid is repeatedly applied to the sealing member. No, as a result, the reliability of hermetic sealing of the container consisting of the insulating base and the metal lid becomes high,
Electronic components such as surface acoustic wave elements housed inside the container can be operated normally and stably for a long period of time.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 shows an embodiment in which the container for accommodating an electronic component of the present invention is applied to a container for accommodating a surface acoustic wave element, wherein 1 is an insulating base, and 2 is a metal lid. The insulating base 1 and the metal lid 2 constitute a container for accommodating the surface acoustic wave element 3 therein.

The insulating substrate 1 is made of an electrically insulating material such as an aluminum oxide sintered body, a mullite sintered body, an aluminum nitride sintered body, a silicon carbide sintered body, a glass ceramic sintered body, etc. Has a mounting area in which a surface acoustic wave element is mounted, and a surface acoustic wave element 3 is bonded and fixed to the mounting area via a resin adhesive 4.

When the insulating base 1 is made of, for example, an aluminum oxide sintered body,
An appropriate organic binder, a plasticizer, and a solvent are added to and mixed with raw material powders such as silicon oxide, magnesium oxide, and calcium oxide to form a slurry, and the slurry is ceramic green by employing a doctor blade method or a calendar roll method. The ceramic green sheet is formed into a sheet (ceramic green sheet). Thereafter, the ceramic green sheet is subjected to a suitable punching process, and a plurality of the sheets are laminated and fired at a high temperature of about 1600 ° C.

The insulating substrate 1 includes a surface acoustic wave element 3
A plurality of metallized wiring layers 5 are formed to extend from the periphery of the region to which the surface acoustic wave element 3 is adhered and fixed to the lower surface of the insulating base 1, and the metallized wiring layer 5 located around the region where the surface acoustic wave element 3 is adhered and fixed is formed. One surface acoustic wave element 3
Are electrically connected via bonding wires 6, and an external electric circuit is electrically connected to a portion extending to the lower surface of the insulating base 1 via a brazing material such as solder.

The metallized wiring layer 5 formed on the insulating substrate 1 is made of a high melting point metal powder such as tungsten, molybdenum, manganese, etc. The metallized wiring layer 5 connects each electrode of the surface acoustic wave element 3 housed inside the container to the outside. It serves to electrically connect to an electric circuit.

The metallized wiring layer 5 is made of, for example, a metal paste obtained by adding a suitable organic binder, a plasticizer, and a solvent to a high melting point metal powder such as tungsten and mixing the metal paste with the upper and lower surfaces of a ceramic green sheet serving as an insulating substrate 1. A predetermined pattern is formed in a predetermined position on the insulating substrate 1 by pre-printing and filling a predetermined pattern in a through hole formed in a ceramic green sheet by a press drilling method in advance by employing a conventionally known screen printing method. .

The metallized wiring layer 5 is coated on the exposed outer surface with a metal having excellent corrosion resistance, such as nickel and gold, and a brazing agent and a wettable metal by plating at a predetermined thickness (nickel: 1 μm to 10 μm, Gold: 0.1 μm to 5 μm
m), the oxidation corrosion of the metallized wiring layer 5 can be effectively prevented, and the connection between the metallized wiring layer 5 and the bonding wire 6 and the brazing material between the metallized wiring layer 5 and the external electric circuit can be effectively prevented. The connection through can be made strong. Accordingly, the outer surface of the metallized wiring layer 5 is sequentially plated with a metal having excellent corrosion resistance such as nickel and gold and a good wettability with a brazing material by a plating method (nickel: 1 μm to 10 μm, gold: 0.1 μm). ~ 5
μm).

The insulating base 1 has a metal lid 2 joined to the upper surface thereof via a sealing member 7, so that an elastic surface is formed inside the container including the insulating base 1 and the metal lid 2. The wave element 3 is accommodated.

The metal lid 2 is made of a metal material such as an iron-nickel-cobalt alloy, an iron-nickel alloy, copper, or aluminum. For example, the metal lid 2 is rolled into an iron-nickel-cobalt alloy ingot. It is formed in a predetermined shape by applying a conventionally known metal working method such as a stamping method or a punching method.

The sealing member 7 for joining the metal lid 2 to the upper surface of the insulating base 1 is made of, for example, an elastic modulus obtained by adding acrylic rubber particles to epoxy resin in an amount of 5 to 50% by weight. Is formed of a material having an appropriate flexibility of 5 GPa or less.

The sealing member 7 has an elastic modulus of 5 GPa or less and has a suitable flexibility, so that the difference between the thermal expansion coefficients of the insulating base 1 and the metal lid 2 is 2.0 × 10 ^{−. 6} / ℃
As described above, even if the thermal stress caused by the difference in the thermal expansion coefficient between the insulating base 1 and the metal lid 2 is repeatedly applied to the sealing member 7, the sealing member 7 is kept on the insulating base 1 and the metal lid 2.
As a result, the reliability of the hermetic sealing of the container composed of the insulating base 1 and the metal lid 2 becomes high, and the surface acoustic wave element 3 accommodated in the container is kept for a long time. It is possible to operate normally and stably.

The joining of the insulating base 1 and the metal lid 2 by the sealing member 7 in which 5 to 50% by weight of acrylic rubber particles are externally added to the epoxy resin is performed.
A resin precursor to be the sealing member 7 is printed and applied in a frame shape by a screen printing method on the upper surface of the substrate, and then the metal lid 2 is placed so as to sandwich the resin precursor therebetween. Heat treatment is performed at a temperature of 120 ° C. to 150 ° C. for 0.5 to 5 hours to thermally cure the resin precursor. In this case, since the temperature at which the resin precursor is thermally cured to form the sealing member 7 is low, even if the heat is applied to the resin adhesive 4 that bonds and fixes the surface acoustic wave element 3 to the insulating base 1, No gas is generated from the adhesive 4 and a part of the resin adhesive 4 is not decomposed. As a result, the surface acoustic wave element 3 can be firmly fixed to the insulating base 1 and the surface acoustic wave The desired characteristics of the element 3 can be sufficiently exhibited.

As the sealing member 7, specifically, an epoxy resin such as a bisphenol A type epoxy resin, a novolak type epoxy resin, a glycidyl ester type epoxy resin, an amine type curing agent, an imidazole type curing agent,
Butyl acrylate, cross-linked polymethyl methacrylate, a resin adhesive containing 50% by weight or more of an epoxy resin containing a curing agent such as an acid anhydride-based curing agent;
Those containing 5 to 50% by weight of acrylic rubber particles made of ethyl acrylate, urethane acrylate or the like by external addition are preferably used.

In addition, the sealing member 7 has an addition amount of the acrylic rubber particles of 5 to the total amount of the epoxy resin.
If the content is less than 5% by weight, the elasticity of the sealing member 7 becomes 5 GPa or more and the flexibility becomes low. As a result, the thermal stress caused by the difference in the thermal expansion coefficient between the insulating base 1 and the metal lid 2 is reduced. Is repeatedly applied to the insulating substrate 1 and the metal lid 2, and when the content exceeds 50% by weight, when the insulating substrate 1 and the metal lid 2 are joined, the sealing member 7
Has poor fluidity, and good sealing cannot be performed. Therefore, it is preferable that the addition amount of the acrylic rubber particles contained in the sealing member 7 be in the range of 5 to 50% by weight based on the total amount of the epoxy resin.

Further, if the average particle diameter of the acrylic rubber particles contained in the sealing member 7 is less than 0.1 μm, the elastic modulus of the sealing member 7 becomes 5 GPa or more and the flexibility is low. As a result, when thermal stress caused by a difference in thermal expansion coefficient between the insulating base 1 and the metal lid 2 is repeatedly applied, the insulating base 1 and the metal lid 2 are separated from the insulating base 1 and the metal lid 2, and 10 μm is removed. If it exceeds, the dispersion in the sealing member 7 becomes non-uniform, and the fluidity at the time of sealing deteriorates, and there is a risk that good sealing cannot be performed. Accordingly, it is preferable that the particles of the acrylic rubber contained in the sealing member 7 have an average particle diameter in a range of 0.1 μm to 10 μm.

Thus, according to the above-mentioned electronic component storage container, the surface acoustic wave element 3 is bonded and fixed to the upper surface of the insulating base 1 via the resin adhesive 4 and the electrodes of the surface acoustic wave element 3 are bonded to the bonding wires 6. Is electrically connected to the metallized wiring layer 5 via the metal substrate 2. Thereafter, the metal cover 2 is joined to the upper surface of the insulating base 1 by the sealing member 7, and the insulating base 1 and the metal cover 2 are formed. Surface acoustic wave element 3 inside the container
Is accommodated in the surface acoustic wave device as a final product.

It should be noted that the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the present invention. Although the surface acoustic wave element has been described as an example of the electronic components to be housed, other electronic parts such as semiconductor elements may be housed.

[0027]

According to the electronic component storage container of the present invention,
The sealing member for joining the insulating base and the lid is formed, for example, by adding acrylic rubber particles to the epoxy resin to 5 to 5 parts.
0% by weight, and the elastic modulus of the sealing member is 5GP.
a, the difference in thermal expansion coefficient between the insulating base and the metal lid is 2.0 × 10 ^−6.
/ ° C or more, and the sealing member peels off from the insulating substrate or the metal lid even if thermal stress caused by the difference in thermal expansion coefficient between the insulating substrate and the metal lid is repeatedly applied to the sealing member. As a result, the reliability of the hermetic sealing of the container consisting of the insulating base and the metal lid is high, and the electronic components such as the surface acoustic wave elements housed inside the container can be normally used for a long time. , And can be operated stably.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of an electronic component storage container according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Insulating base 2 ... Metal lid 3 ... Surface acoustic wave element (electronic component) 4 ... Resin adhesive 5 ... Metallized wiring layer 7 ... Sealing member

Claims (2)

[Claims] An electronic component storage container in which an insulating base and a lid are joined via a sealing member, and an electronic component is stored in a container including the insulating base and the lid. The difference in thermal expansion coefficient between the insulating base and the lid is 2.0 × 10 ⁻⁶ /
An electronic component storage container, wherein the elastic modulus of the sealing member is 5 GPa or less when the temperature is not less than ° C. 2. The electronic component storage container according to claim 1, wherein the sealing member is made of an epoxy resin containing 5 to 50% by weight of acrylic rubber particles by external addition. .