JPH05186241A - Composition for sealing - Google Patents

Abstract

PURPOSE:To enable to seal a semiconductor at a low temperature of <=380 deg.C. CONSTITUTION:The power of a glass composition comprising 25-45mol.% of V2O5, 25-45mol.% of PbO, 10-35mol.% of TeO, 0.1-5.0mol.% of SnO2, 0.1-5.0mol.% of TiO2, 0.1-5.0mol.% of ZnO, and 1.0-10mol.% one kind or more of Nb2, Ta2O5 WO3 and MnO2 is compounded with 10-50mol.% of a refractory filler.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sealing composition suitable for sealing a semiconductor package using alumina or the like, and more particularly to a sealing composition capable of sealing at a low temperature.

[0002]

2. Description of the Related Art Since the surface of a semiconductor is extremely sensitive to moisture and impurities, it is common to put it in a package that considers not only mechanical protection but also protection against moisture, and hermetically seal this. is there. Alumina-based packages are often used as such packages, but molded products made of glass or resin are also used.

When a semiconductor chip is sealed using these packages, it is necessary to seal at a temperature as low as possible in order to reduce the influence of heat on the semiconductor chip. In recent years, as the degree of integration of integrated circuits has increased, the above requirements have become more and more severe, and in order to seal a semiconductor package made of alumina or the like at 380 ° C.
A sealing composition that can be sealed below is desired.

Further, as this kind of sealing composition,
1) A resin such as an epoxy resin is used as a matrix, and a ceramic powder such as silica is mixed for the purpose of lowering the coefficient of thermal expansion and improving the strength, and the resin is hardened and adhered. 2) Low melting point glass It has been conventionally used to add an organic binder to a mixture of a frit and a filler, melt the glass frit by firing, and scatter the organic binder to adhere the glass frit.

[0005]

However, in the case of using the sealing composition of 1) above, since the resin is used as a matrix, a difference in thermal expansion is likely to occur between the sealing composition and the package made of alumina or the like. Deformation or cracking of the element due to
There is an inconvenience that cracks are likely to occur.

When the sealing composition of 2) above is used, the difference in thermal expansion between the composition and the package can be suppressed to a relatively small value, but the composition is heated to a high temperature in order to melt the glass frit. However, there is an inconvenience that the semiconductor chip is adversely affected by heat.

The present invention has been made in view of the above problems of the prior art, and an object thereof is to enable a semiconductor package to be sealed at a low temperature of 380 ° C. or lower in a sealing composition using a glass frit. The present invention provides a sealing composition.

[0008]

In order to achieve the above object, the sealing composition of the present invention, in mol%, is essentially V
₂ O ₅ : 25-45%, PbO: 25-45%, TeO
₂ : 10-35%, SnO ₂ : 0.1-5.0%, Ti
O ₂ : 0.1 to 5.0%, ZnO: 0.1 to 5.0%,
_{Nb 2 O 5 + Ta 2 O} 5 + WO 3 + MnO 2: 1.0~
A sealing composition composed of 10% low melting glass powder and refractory filler powder, wherein the refractory filler powder is% by volume.
Is 10 to 50%.

The present invention will be described in detail below with reference to preferred modes.

The sealing composition of the present invention contains glass powder having a specific composition and refractory filler powder, and is heat-treated at 380 ° C. or lower, for example 350 ° C.
It is sufficiently fluidized by a heat treatment to some extent, and in particular, a semiconductor package made of alumina or the like can be hermetically sealed.

The reason why the composition is limited will be described below.

When V ₂ O ₅ is less than 25%, the viscosity of the glass becomes too large, and when it exceeds 45%,
It is not preferable because the tendency of glass to crystallize increases and the glass does not flow.

If PbO is less than 25%, the melting temperature of the glass will be high, and if it exceeds 45%, the crystallization tendency of the glass will be large.

If the content of TeO ₂ is less than 10%, the viscosity of the glass becomes large and it becomes difficult to flow, and if it exceeds 35%, the expansion coefficient of the glass becomes too large.

When SnO ₂ is less than 0.1%, it has no effect on lowering the melting point, and when it exceeds 5%, the viscosity of the glass becomes large.

If TiO ₂ is in the range of 0.1 to 5%, it is effective in stabilizing the glass.

If the content of ZnO is less than 0.1%, there is no effect in lowering the viscosity, and if it exceeds 5%, the tendency of crystallization increases.

Nb ₂ O ₅ , Ta ₂ O ₅ , WO ₃ , MnO
₃ is 1.0-10% of at least one of them
If it is contained within the range, it is effective in stabilizing the glass.

The refractory filler powder is added for the purpose of expansion matching, but unless it is within the range of 10 to 50% by volume, expansion matching and the fluidity of the glass are affected and the airtight sealing is performed. I can't wear it.

In the present invention, the above composition is in mol%,
_{V 2 O 5: 25~45%,} PbO: 25~45%, Te
O ₂ : 10-35%, SnO ₂ : 0.5-4.5%, T
_{iO 2: 0.5~4.5%, ZnO:} 0.5~4.5%
And Nb ₂ O ₅ , Ta ₂ O ₅ , WO ₃ , MnO ₂
It is more preferable that the composition contains 1.5 to 9% of at least one of them. In the following description,% means mol% unless otherwise specified.

The size of the glass powder having the above composition is
A particle size of about 1 to 10 μm is preferable.

The glass powder may be manufactured by a usual method. That is, V ₂ O ₅ , PbO, TeO ₂ , SnO
₂ , TiO ₂ , ZnO, Nb ₂ O ₅ , Ta ₂ O ₅ , WO
₃ , MnO ₂ is blended so as to satisfy the above ratio, heated and melted, and then rapidly cooled to manufacture a glass block. Next, this glass block is crushed into a glass powder using, for example, a ball mill.

The refractory filler powder used in the present invention is preferably one or two or more refractory filler powders selected from, for example, lead titanate solid solution, cordierite and β-eucryptite. The diameter is preferably about 1 to 10 μm, which is about the same as the particle size of the glass powder, and the compounding amount thereof is preferably 10 to 50% by volume with respect to the total of the glass powder and the refractory filler.

The refractory filler powder is added to match the expansion coefficient of the sealing composition with the semiconductor package and to improve the strength, but if it is less than 10% by volume, the effect is not exhibited. If it exceeds 50% by volume, the fluidity of the glass is significantly deteriorated, and the semiconductor package cannot be hermetically sealed.

Any method may be used for mixing the glass powder and the refractory filler powder. For example, when the glass block is crushed by a ball mill, the refractory filler is added, and the crushing and mixing are performed simultaneously. Alternatively, each may be made into powder having a predetermined size in advance and then mixed.

The thus produced sealing composition of the present invention can be used for sealing a semiconductor package in the same manner as a conventional sealing composition. That is, for example, after mixing the sealing composition and the organic binder, the mixture is attached to a portion of the semiconductor package to be sealed, and heated to melt the sealing composition and to scatter the organic binder. , Seal the package. Since the sealing composition of the present invention is sufficiently fluidized by heat treatment at a temperature of 380 ° C. or lower, it can be sealed at a low temperature, and is particularly suitable for sealing a semiconductor package made of alumina.

[0027]

The sealing composition of the present invention has a specified glass composition, and thus it sufficiently flows by heat treatment at a temperature of 380 ° C. or lower.

Further, since a refractory filler is blended, the coefficient of thermal expansion of the sealing composition is matched with that of the semiconductor package,
The strength can be improved.

Therefore, the semiconductor package is placed at 380 ° C.
The following sealing is possible, and it is particularly suitable for sealing a semiconductor package made of alumina.

[0030]

EXAMPLES V ₂ O ₅ , PbO, TeO ₂ , SnO ₂ , T
iO ₂ , ZnO, Nb ₂ O ₅ , Ta ₂ O ₅ , WO ₃ , M
nO ₂ is blended in a ratio shown in Table 1. After mixing the blended batches, the batch is put into a platinum crucible, heated in an electric furnace at 600 to 900 ° C. for 30 to 60 minutes to be melted, and then rapidly cooled to form a plate or a flake. The particle size of the molded product thus obtained is 1-10 μm using a ball mill.
Samples A to H crushed to about m and shown in Table 1 as mol%
A low melting point glass powder was obtained.

[0031]

[Table 1]

The low melting glass powder thus obtained was mixed with a refractory filler powder having a particle size of about 1 to 10 μm at a ratio shown as a volume% in Tables 2 and 3, and Examples 1 to 1 were used.
A sealing composition of 0 was obtained.

[0033]

[Table 2]

[0034]

[Table 3]

Tables 2 and 3 show the measurement results of the thermal expansion coefficient, the fluid diameter and the sealing temperature for the sealing compositions of Examples 1-10, respectively.

The coefficient of thermal expansion is measured by a differential expansion meter.
Obtained from the average coefficient of thermal expansion from 30 to 250 ° C., the flow diameter was obtained by collecting an amount (gram) of the sealing composition corresponding to the specific gravity of each sealing composition, and dry-pressing into a cylindrical column having a diameter of 12.5 mm. Then, the sample was heated to each sealing temperature and taken out, and the diameter at that time was measured. If the flow diameter is 18 mm or more, a sufficient sealed state can be obtained.

From the results of Tables 2 and 3, Examples 1 to 1 satisfying the glass composition of the present invention and containing a refractory filler
The compositions of 10 all have a sealing temperature of 350 to 360 ° C.
It is clear that the coefficient of thermal expansion is low, the coefficient of thermal expansion is small, and the fluidity is good.

[0038]

As described above, since the sealing composition of the present invention specifies the glass composition and contains the refractory filler, the semiconductor package should be sealed at a low temperature of 380 ° C. or lower. It is possible to improve the reliability of the element by hermetically sealing without adversely affecting the semiconductor, and it is particularly suitable for sealing a semiconductor package using alumina. Moreover, since the sealing composition of the present invention does not contain fluorine or thallium oxide as a component, it is possible to eliminate the possibility of adversely affecting the natural environment or the human body.

Claims (2)

[Claims] 1. In mol% essentially V ₂ O ₅ : 25-4.
5%, PbO: 25-45%, TeO ₂ : 10-35
%, SnO ₂ : 0.1 to 5.0%, TiO ₂ : 0.1
5.0%, ZnO: 0.1-5.0%, Nb ₂ O ₅ + T
a ₂ O ₅ + WO ₃ + MnO ₂ : A sealing composition comprising a low melting point glass powder consisting of 1.0 to 10% and a refractory filler powder, the refractory filler powder being 10 to 50% by volume.
A composition for sealing, which is 2. The sealing composition according to claim 1, wherein the refractory filler powder is one or more selected from lead titanate solid solution, cordierite, and β-eucryptite.