JP6963413B2 - Glass composition for sealing - Google Patents

Description

The present invention relates to a sealing glass composition used for sealing electronic components and the like.

Electronic components including semiconductors may be sealed, sealed, etc. with various glasses, resins, etc. in order to protect them from the external environment. An example of such an electronic component is a thermistor. A thermistor is an electronic component used as a temperature sensor by utilizing the characteristic that the electric resistance of a semiconductor changes significantly with respect to a temperature change. The thermistor is also coated and sealed with glass or the like in order to prevent deterioration in the environment, especially when it is used in a high temperature or an oxidizing atmosphere. FIG. 1 shows a basic configuration of a bead type thermistor (lead type), which is a typical example of a thermistor. Two lead wires 13 are connected to the thermistor 10 via a semiconductor element 12, and the thermistor 10 is coated and sealed with a sealing material layer 11 so as to cover the semiconductor element 12 and the lead wires 13. As the sealing material constituting the sealing material layer 11, glass, resin or the like has been conventionally used, but glass is particularly frequently used in terms of excellent heat resistance and the like.

When glass is used as the sealing material, in addition to having high electrical resistance, the coefficient of thermal expansion of the semiconductor element and lead wire is adjusted so that cracks and gaps do not occur when the semiconductor element and lead wire are coated and sealed. It is required to have the same or close coefficient of thermal expansion.

As a sealing material for such a temperature sensor, for example, borosilicate glass (Patent Document 1 and Patent Document 2) has been proposed. Further, as a sealing material for a temperature sensor used at a higher temperature, a crystallized glass is used. For example, crystallized glass (Patent Document 3) in which crystals of lanthanoid titanoide crystals or diopside crystals are precipitated is also known.

JP-A-2002-037641 WO2006 / 035882, etc. Japanese Unexamined Patent Publication No. 2008-120648

When glass is used as a sealing material for electronic parts, it is required to have higher heat resistance. That is, even if the electronic component is exposed to a high temperature, the sealing material is required to surely perform the sealing function without causing softening and deformation. It can be said that such a requirement is becoming more prominent in temperature sensors (thermistors) and the like.

An example of a device in which a temperature sensor is used is a power generation device. In recent years, in view of the increase in carbon dioxide emissions and environmental problems such as acid rain _{, in order to minimize the generation of harmful gases such as CO 2} and NOx, the combustion system of the power generation equipment should be kept in the optimum operating condition. Is required. In order to optimize the combustion state of the combustion system in this way, it is necessary to control the temperature of the combustion system by a temperature control system including a temperature sensor and the like. Moreover, the temperature range to be controlled needs to cover a higher temperature range as well.

However, the heat resistance of the glass, which is the sealing material of the conventional temperature sensor, is not yet sufficient. Further, although a temperature sensor using crystallized glass as a sealing material does not soften and deform even in a relatively high temperature range, it is difficult to maintain a stable state in a further high temperature range (for example, 1100 ° C. or higher), so that it is practically used. From this point of view, anxiety remains.

Therefore, a main object of the present invention is to provide a glass composition capable of forming a sealing material which has physical properties suitable for a sealing process of electronic parts and can withstand a higher temperature range.

As a result of diligent research in view of the problems of the prior art, the present inventor has found that the above object can be achieved by a glass composition having a specific composition, and has completed the present invention.

That is, the present invention relates to the following encapsulating glass composition and encapsulant.
1. 1. A glass composition for producing a crystallized glass encapsulant containing SrO-SiO _{2 crystal, at least the following components;}
1) SiO ₂ : 41-55 mol%,
2) SrO: 6-40 mol%,
3) ZnO: 1 to 20 mol%,
4) Al ₂ O ₃ : 3.1 to 25 mol% and 5) RO (where R indicates at least one of Mg, Ca and Ba): 0 to 20 mol% in total.
A glass composition for sealing, which comprises.
2. The above ingredients
1) SiO ₂ : 42-55 mol%,
2) SrO: 6-40 mol%,
3) ZnO: 1 to 20 mol%,
4) Al ₂ O ₃ : 3.1 to 25 mol% and 5) RO (where R indicates at least one of Mg, Ca and Ba): total 0 to 20 mol%, according to item 1 above. The sealing glass composition according to the above.
3. 3. The above ingredients
1) SiO ₂ : 41-55 mol%,
2) SrO: 6-40 mol%,
3) ZnO: 1 to 20 mol%,
4) Al ₂ O ₃ : 3.1 to 25 mol% and 5) RO (where R indicates at least one of Mg, Ca and Ba): 0 to 17 mol% in total.
The sealing glass composition according to Item 1 above.
4. The above ingredients
1) SiO ₂ : 41-55 mol%,
2) SrO: 6-40 mol%,
3) ZnO: 1 to 20 mol%,
4) Al ₂ O ₃ : 3.1 mol% or more and less than 13 mol% and 5) RO (where R indicates at least one of Mg, Ca and Ba): 0 to 20 mol% in total.
The sealing glass composition according to Item 1 above.
5. The above ingredients
1) SiO ₂ : 41-55 mol%,
2) SrO: 6-40 mol%,
3) ZnO: 1 to 20 mol%,
4) Al ₂ O ₃ : 13 to 25 mol% and 5) RO (where R indicates at least one of Mg, Ca and Ba): 0 to 20 mol% in total.
The sealing glass composition according to Item 1 above.
6. SrO-SiO ₂ system crystallized glass encapsulant
(1) At least the following components;
1) SiO ₂ : 41-55 mol%,
2) SrO: 6-40 mol%,
3) ZnO: 1 to 20 mol%,
4) Al ₂ O ₃ : 3.1 to 25 mol% and 5) RO (where R indicates at least one of Mg, Ca and Ba): 0 to 20 mol% in total.
Including
(2) as SrO-SiO ₂ based _crystal, comprising SrZn 2 _Si 2 _{O 7 crystals,} Sr 2 ZnSi ₂ O _{7 crystals,} at least one of SrAl 2 _Si 2 _{O 8} crystal and _Sr 2 _Al 2 SiO ₇ crystal,
A SrO-SiO ₂ system crystallized glass encapsulant characterized by this.
7. _{Item 5. The SrO-SiO 2} system crystallized glass encapsulant according to Item 5, wherein the coefficient of thermal expansion at 50 to 850 ° C. is 35 to 100 × ^{10-7 / ° C.}
8. An electronic device in which electronic components are sealed by _{the SrO-SiO 2} system crystallized glass encapsulant according to Item 6 or 7.
9. _{A method for producing a SrO-SiO 2-} based crystallized glass encapsulant, which comprises a step of heat-treating the encapsulating glass composition according to Item 1 at a temperature of 1000 to 1300 ° C.

According to the sealing glass composition of the present invention (the glass composition of the present invention), a sealing material having physical properties suitable for the sealing process of electronic parts and capable of withstanding a higher temperature region after firing is formed. be able to. That is, the glass composition of the present invention can suitably provide the encapsulant of the present invention.

The glass composition of the present invention is fired at the time of use, and since the _{crystallized glass containing the SrO-SiO 2} system crystal (encapsulating material of the present invention) is formed by the firing, the melting point of the crystal is formed from around 1100 ° C. Excellent heat resistance can be exhibited in the range of less than (about 1350 ° C.). Moreover, since the crystallized glass exhibits a coefficient of thermal expansion close to that of electronic components (for example, metals and / or semiconductors), deterioration, deformation, etc. can be effectively suppressed or prevented even when exposed for a long period of time under high temperature conditions. In addition, since there is no risk of viscosity decrease, it can be suitably used as a sealing material under high temperature conditions.

Further, even in the stage of the sealing step (during firing) using the glass composition of the present invention, the glass composition of the present invention can exhibit high fluidity, and therefore has excellent wettability, adhesion or followability to electronic parts. Effective sealing without gaps, pores, etc. (particularly, coating sealing in which electronic parts are directly covered with the sealing material of the present invention) can be performed. In addition, this can also contribute to the efficiency of the sealing process (and thus the manufacture of electronic devices).

The glass composition and encapsulant of the present invention having such characteristics can be suitably used for encapsulation for protecting electronic components (semiconductor elements and the like) from the external environment, for example.

It is a schematic diagram which shows the structure of a general bead type thermistor.

10 Thermistor 11 Encapsulant layer 12 Semiconductor element 13 Lead wire

1. 1. Glass composition for sealing
(1) Glass composition for sealing
The sealing glass composition of the present invention (the glass composition of the present invention) is a glass composition for producing a crystallized glass sealing material containing _{SrO-SiO 2 system crystals, and has at least the following components;}
1) SiO ₂ : 41-55 mol%,
2) SrO: 6-40 mol%,
3) ZnO: 1 to 20 mol%,
4) Al ₂ O ₃ : 3.1 to 25 mol% and 5) RO (where R indicates at least one of Mg, Ca and Ba): 0 to 20 mol% in total.
It is characterized by including. Hereinafter, each component of the sealing glass composition of the present invention will be described.

SiO ₂
In the glass composition of the present invention, SiO ₂ is a glass network forming component, which mainly improves the stability of the glass during the production of glass and at the time of using the glass composition of the present invention (that is, firing of the glass composition of the present invention). _{It is an effective component for producing SrO-SiO 2} system crystals (crystals of the present invention) in the body). The crystal of the present invention is not particularly limited as long as it is a crystal containing _{SrO and SiO 2 , but in particular, SrZn 2} Si ₂ O ₇ crystal, Sr ₂ ZnSi ₂ O ₇ crystal, SrAl ₂ Si ₂ O ₈ crystal and Sr ₂ It is preferably at least one of Al ₂ SiO _{7 crystals.} The crystallized glass in which these crystals are precipitated can obtain an excellent effect in that it has high heat resistance.

_{The content of SiO 2} in the glass composition of the present invention is usually 41 to 55 mol%, preferably 42 to 55 mol%, and more preferably 42 to 47 mol%. If _{the content of SiO 2} is less than 41 mol%, crystals may precipitate in the glass. When crystals are deposited in the glass, the glass powder obtained by crushing the crystals starts crystallization earlier at the time of firing, and as a result, the fluidity is lowered at the initial stage after the start of firing, and as a result, the glass powder is sealed after firing. There is a risk that a gap will be created between the stopper and the object, making it impossible to perform the desired sealing. Moreover, when the glass powder is fired, SrO-SiO ₂ type crystals may not be sufficiently produced. On the other hand, when _{the content of SiO 2} exceeds 55 mol%, glass is not formed, or even if glass is formed, the value of the coefficient of thermal expansion increases due to abnormal expansion due to precipitation _{of SiO 2 crystals after firing.} May increase.

SrO
In the glass composition of the present invention, SrO is mainly an effective component for precipitating _{SrO-SiO 2} system crystals in the crystallized glass obtained by firing the glass composition of the present invention.

The content of SrO in the glass composition of the present invention is usually 6 to 40 mol%, preferably 10 to 38 mol%, and more preferably 12 to 36 mol%. When the SrO content is less than 6 mol%, the desired crystals are not sufficiently precipitated in the crystallized glass after firing, and the residual ratio of the glass phase (amorphous phase) to the crystal phase becomes large. There is a risk that good heat resistance cannot be imparted to the glass. If the SrO content exceeds 40 mol%, crystals will precipitate in the glass and the fluidity when firing the glass composition of the present invention will be insufficient, so that the desired sealing may not be possible. ..

ZnO
In the glass composition of the present invention, ZnO is mainly a component necessary for producing _{SrO-ZnO-SiO 2 type crystals among the crystals of the present invention.}

The content of ZnO in the glass composition of the present invention is usually 1 to 20 mol%, preferably 3 to 18 mol%, more preferably 5 to 16 mol%, and most preferably 8 to 13 mol%. do. If the ZnO content is less than 1 mol%, the crystallinity of the crystallized glass obtained by firing the glass composition of the present invention may be insufficient. If the ZnO content exceeds 20 mol%, the glass may not be formed, or even if the glass is formed, the crystallization temperature may become too low, and the fluidity of the glass composition of the present invention during firing may be too low. May decrease.

Al ₂ O ₃
In the glass composition of the present invention, Al ₂ O ₃ is mainly an optional component for improving the stability of the glass during production and adjusting the crystallization start temperature. In addition, Al ₂ O ₃ is also a useful component for forming _{SrO-Al 2} O _{3 -SiO 2} system crystals that contribute to the improvement of heat resistance in crystallized glass in the crystals of the present invention.

_{The content of Al 2} O ₃ in the glass composition of the present invention is usually 3.1 to 25 mol%, preferably 4 to 16 mol%. Therefore, for example, it can be 3.1 mol% or more and less than 13 mol% (particularly 3.1 mol% or more and 12 mol% or less). It can also be, for example, 13 to 25 mol% (particularly 13.3 to 15.5 mol%). When _{the content of Al 2} O ₃ is less than 3.1 mol%, the heat resistance deteriorates because it does not precipitate sufficiently _{especially when trying to generate SrO-Al 2} O _{3 -SiO 2 system crystals.} There is. If _{the content of Al 2} O ₃ exceeds 25 mol%, the difference between the glass softening temperature and the crystallization start temperature may become too small, and the airtightness may deteriorate.

Further, in the present invention, the thermal expansion characteristics of the obtained crystallized glass can be freely and surely controlled by _{mainly changing the Al 2} O _{3 content within the above range.} That is, _{by setting the Al 2} O ₃ content within the range of 3.1 mol% or more and less than 13 mol%, a relatively large coefficient of thermal expansion (particularly 60 to 100 × ^10-7 / ° C., preferably 80 to 80 to It can be controlled to 96 × 10 ^{-7 / ° C.).} On the other hand, _{by setting the Al 2} O ₃ content within the range of 13 mol% or more and 25 mol% or less, a relatively small coefficient of thermal expansion (particularly 35 to 65 × ^10-7 / ° C., preferably 40 to 62 ×) It can be controlled to ^{10-7 / ° C.).} As described above, in the glass composition of the present invention, the composition can be appropriately used depending on the material of the material to be sealed, and as a result, the thermal expansion characteristics are made as close as possible to the material to be sealed, so that the sealing is higher. It is possible to realize the stopping property.

RO
In the glass composition of the present invention, RO (where R indicates at least one of Mg, Ca and Ba) is an optional component effective for lowering the melting temperature during glass production and facilitating glass production. It is also effective as a component that lowers the softening point.

The total amount of RO in the glass composition of the present invention is usually 0 to 20 mol%, preferably 018 mol%, more preferably 0 to 17 mol%, more preferably 0 to 10 mol%, and most. It is preferably 0 to 5 mol%. When the RO content exceeds 20 mol%, the softening point of the glass is lowered too much, so that the heat resistance may be lowered. In the following, the role and preferable content of each component of MgO, CaO and BaO will be described.

MgO is an optional component that is effective mainly for lowering the melting temperature during glass production and facilitating glass production, and is also a component that lowers the softening point of glass.

The content of MgO in the glass composition of the present invention is preferably in the range of 20 mol% or less, more preferably 18 mol or less, and particularly preferably 15 mol% or less. If the MgO content exceeds 20 mol%, glass may not be formed and the crystallization temperature of the crystallized glass by the glass composition of the present invention may become too low. _{In addition, MgO-CaO-SiO 2} type crystals that melt at a relatively low temperature are likely to precipitate in the crystallized glass produced by the glass composition of the present invention, and the heat resistance of the crystallized glass in a high temperature range may deteriorate. In addition, the coefficient of thermal expansion of the crystallized glass may increase too much. Considering the softening point, fluidity, and coefficient of thermal expansion of the obtained glass, the content of MgO is more preferably 10 mol% or less, further preferably 5 mol% or less, and further preferably 0. It is ~ 1 mol%, and most preferably it is substantially free.

In addition, in the present invention, "substantially not contained" does not prohibit even the case where it is contained at the impurity level, for example, at the level where it is simply contained as an impurity in the raw material for producing glass or the like. If so, its inclusion is acceptable. More specifically, if their total weight is 1000 ppm or less in terms of oxides, even if they are contained in the sealing glass composition of the present invention, there is little possibility that they will cause a problem. Does not correspond to ".

In the present invention, BaO is a component having mainly 1) an action of lowering the softening point, 2) an action of lowering the melting temperature during glass production, or 3) an action of increasing the coefficient of thermal expansion.

The content of BaO in the glass composition of the present invention is usually preferably in the range of 0 to 20 mol%, more preferably 18 mol or less, and particularly preferably 0 to 15 mol%. If the BaO content exceeds 20 mol%, the crystallization temperature may become too low even if glass is produced. _{Further, since the BaO-ZnO-SiO 2} system crystals having a relatively high coefficient of thermal expansion are likely to precipitate in the crystallized glass according to the glass composition of the present invention, the coefficient of thermal expansion of the crystallized glass may increase too much. Considering the softening point, fluidity, etc. of the obtained glass, the content of BaO is preferably 0 to 5 mol%, more preferably 0 to 1 mol%.

CaO is a component that is mainly effective for lowering the melting temperature during glass production and facilitating glass production, and is a component that lowers the softening point of glass.

The content of CaO in the glass composition of the present invention is usually preferably in the range of 0 to 20 mol%, and more preferably 18 mol or less. If the CaO content in the glass composition of the present invention exceeds 20 mol%, the crystallization temperature may become too low even if the glass is obtained. Considering the softening point, fluidity, etc. of the obtained glass, the CaO content is more preferably 0 to 5 mol%, still more preferably 0 to 1 mol%.

Other ingredients
a) Alkali metal
Since alkali metals such as Na and K may promote the reaction with peripheral members particularly in a high temperature region, it is preferable that the glass composition of the present invention does not substantially contain an alkali metal.

b) Boron
B ₂ O ₃ makes it easy to stabilize the glass state in the process of producing glass. _{The content of B 2} O ₃ in the glass composition of the present invention is usually preferably in the range of 0 to 10 mol%. _{If the content of B 2} O ₃ in the glass composition of the present invention exceeds 10 mol%, glass may not be obtained. Considering the softening point, fluidity, etc. of the obtained glass, _{the content of B 2} O ₃ is more preferably 0 to 5 mol%, and most preferably 0 to 1 mol%.

c) Neutral component
If the above relationship is satisfied between the contents of SiO ₂ , Al ₂ O ₃ , ZnO and SrO in the glass composition of the present invention, then the physical properties of the glass composition of the present invention and the crystallized glass A neutral component that does not have a large effect can be added as long as the effect of the present invention is not significantly impaired. Examples of this neutral component include at least one such as _{Y 2} O ₃ , La ₂ O ₃ , TiO ₂ , ZrO ₂ , and CeO _2. Generally, the content of these components can be appropriately set within a range in which the total _{of SiO 2} , SrO, ZnO, Al ₂ O ₃ , B ₂ O _{3 and RO is 95 mol% or more.}

As described above, the glass composition of the glass composition of the present invention may be adjusted so that each component is within the above-mentioned content range. Therefore, for example, 1) SiO ₂ : 42 to 47 mol%, 2) SrO: 17 to 34 mol%, 3) ZnO: 8 to 15 mol%, 4) Al ₂ O ₃ : 4 to 15 mol% and 5) RO : A glass composition containing 0 to 5 mol% can be preferably adopted.

(2) Form of glass composition for sealing, etc. The form of the glass composition of the present invention is not limited, but it is usually preferably in the form of powder. The particle size in this case is not particularly limited, but it is preferable that the average particle size is 2 to 10 μm and the maximum particle size is 150 μm or less (particularly 110 μm or less). In particular, when an electronic component is coated and sealed using the glass composition of the present invention, the glass powder is required to shrink once during firing and soften and flow to wet the surface of the object to be processed (electronic component). By controlling the particle size, higher fluidity can be obtained during firing.

That is, if the particle size of the glass powder is too small, crystallization starts earlier, which may reduce the flowability during sealing and firing and hinder the flow, and the number of times the sealing material is applied and fired. There is a risk of increasing the manufacturing cost of products manufactured using the sealing material. On the other hand, coarse powder having an excessively large particle size causes a problem that the powder particles settle and separate when the powder is pasted, or when the powder is applied or dried, and the crystallization becomes non-uniform or insufficient. It is easy to cause insufficient strength of the fired body. Therefore, it is preferable to adjust the particle size by removing fine powder and coarse powder (particularly coarse powder) by an operation such as classification. As described above, in the glass composition of the present invention, it is preferable to adjust the particle size of the powder so that the average particle size is 2 to 10 μm and the maximum particle size is 150 μm or less (particularly 110 μm or less).

The glass transition point (Tg) of the glass composition of the present invention is not limited, but is usually in the range of about 680 to 800 ° C. Therefore, it can be set to, for example, 690 to 770 ° C. Further, for example, it can be set to 650 to 720 ° C.
The softening point (Ts) of the glass composition of the present invention is not limited, but is usually in the range of about 700 to 900 ° C. Therefore, it can be set to, for example, 760 to 880 ° C. Further, for example, it can be set to 760 to 850 ° C.
Further, the crystallization start temperature (Tx) of the glass composition of the present invention is not limited, but is usually in the range of about 750 to 1100 ° C. Therefore, it can be set to, for example, 900 to 1050 ° C. It can also be set to, for example, 790 to 950 ° C.

In the glass composition of the present invention, from the viewpoint of glass flowability, airtightness, etc., it is particularly preferable that the difference ΔT between the crystallization start temperature (Tx) and the softening point (Ts) is large. For example, the ΔT may be 20 ° C. or higher, further 60 ° C. or higher, further 70 ° C. or higher, and particularly 100 ° C. or higher. By controlling to a larger ΔT in this way, it is possible to secure a sufficient time for the glass to crystallize, and as a result, good flowability and high airtightness can be obtained more reliably. .. The upper limit of ΔT is not limited, but may be, for example, about 200 ° C.

(3) Method for Producing Glass Composition for Encapsulation The method for producing the glass composition of the present invention is not particularly limited, and for example, 1) raw materials prepared so as to have the composition of the glass composition of the present invention are mixed. Step (Mixing step), 2) Preparing molten glass by melting the obtained mixture at a temperature of 1400 to 1600 ° C. (Melting step), 3) Cooling the molten glass without crystallizing it (Mixing step) It can be manufactured by a manufacturing method including cooling).

As the raw material, a compound that is a source of the glass component may be used as a starting material. Usually, oxides of elements (Si, Ca, Al, Zn, etc.) contained in the glass composition of the present invention may be used as a starting material, but hydroxides, carbonates, nitrates and the like can also be used. That is, SiO ₂ or the like for _{Si, SrO or SrCO 3} or the _{like for Sr, Al 2} O ₃ or Al (OH) ₃ or the like for Al, ZnO or the like for Zn can be appropriately used. As these raw materials, powders may usually be used, and these powders can be uniformly mixed to prepare a mixed powder.

A molten glass is prepared by melting the mixture (mixed powder) thus obtained at a temperature of usually 1400 to 1600 ° C. The melting atmosphere is not limited, but usually the melting step may be carried out in the atmosphere (or in an oxidizing atmosphere) under atmospheric pressure.

Next, in the cooling step, the molten glass is cooled without crystallizing. Such cooling conditions may be the same as in the case of known glass production, and for example, a method of bringing molten glass into contact with a cooling roll made of stainless steel to quench it can be adopted.

Although the glass composition of the present invention is obtained in this way, known treatments such as pulverization and classification may be performed if necessary. When adjusting the particle size by pulverization, classification, etc., it is preferable to adjust the particle size so that the average particle size is 2 to 10 μm as described above and the maximum particle size is 150 μm or less (particularly, the maximum particle size is 110 μm or less). ..

(3) Use of sealing glass composition
The glass composition of the present invention can be used, for example, in the form of powder (dry powder), but is a liquid composition such as a slurry or paste in which the glass composition of the present invention in powder form is dispersed in a binder and / or a solvent. It can also be used in the form.

When the glass composition of the present invention is used as a liquid composition, it may be prepared by mixing at least one of a solvent and an organic binder. For example, a liquid composition can be suitably prepared by mixing the powdered glass composition of the present invention with at least one of a solvent and an organic binder. When preparing the liquid composition, the average particle size of the powder of the glass composition of the present invention is not particularly limited, but is usually preferably 2 to 10 μm, and more preferably 5 to 10 μm. Further, the powder preferably has a maximum particle size of 150 μm or less, particularly 110 μm or less.

The organic binder is not particularly limited, and can be appropriately adopted from known binders according to the specific use (object to be sealed, etc.) of the glass composition of the present invention. Examples thereof include, but are not limited to, cellulose resins such as ethyl cellulose.

The solvent may be appropriately selected from known organic solvents according to the type of the binder used and the like. For example, in addition to alcohols such as ethanol and isopropanol, organic solvents such as terpineol (a mixture of α-terpineol or β-terpineol containing α-terpineol as a main component and γ-terpineol) can be mentioned, but are not limited thereto. .. The organic solvent may be used alone or in combination of two or more.

Further, in the present invention, in the preparation of the above liquid composition, known additives such as a plasticizer, a thickener, a sensitizer, a surfactant, a dispersant, a colorant and the like are appropriately added, if necessary. Can be blended.

In the present invention, the glass composition of the present invention can be used to seal electronic components. The sealing method itself can be carried out according to a known sealing method. For example, in addition to a method including a step of directly covering with the glass composition of the present invention so as to be in contact with the surface of an object to be sealed such as an electronic component and a step of firing the glass composition of the present invention arranged on the surface, the electronic component. A method including a step of arranging the glass composition of the present invention between the container accommodating the glass and the lid material thereof and a step of firing the arranged glass composition of the present invention can be adopted.

In this case, when coating or the like is performed using the glass composition of the present invention, a method of arranging the liquid composition as it is in a required place in the form of a powder, or a method of applying the liquid composition according to a known method (roller, spray, etc.), etc. Should be taken. In addition, a method in which the glass composition of the present invention is prepared in advance as a predetermined molded body and the molded body is arranged at a required position can also be adopted.

2. SrO-SiO ₂ system crystallized glass encapsulant The present invention is an SrO-SiO ₂ system crystallized glass encapsulant.
(1) At least the following components;
1) SiO ₂ : 41-55 mol%,
2) SrO: 6-40 mol%,
3) ZnO: 1 to 20 mol%,
4) Al ₂ O ₃ : 3.1 to 25 mol% and 5) RO (where R indicates at least one of Mg, Ca and Ba): 0 to 20 mol% in total.
Including
(2) as SrO-SiO ₂ based _crystal, comprising SrZn 2 _Si 2 _{O 7 crystals,} Sr 2 ZnSi ₂ O _{7 crystals,} at least one of SrAl 2 _Si 2 _{O 8} crystal and _Sr 2 _Al 2 SiO ₇ crystal,
The SrO-SiO ₂ system crystallized glass encapsulant (encapsulating material of the present invention) is included.

The encapsulant of the present invention is substantially composed of SrO-SiO ₂ system crystallized glass. As the SrO-SiO ₂ system crystal, at least one crystal phase of _{SrZn 2} Si ₂ O ₇ crystal, Sr ₂ ZnSi ₂ O ₇ crystal, SrAl ₂ Si ₂ O ₈ crystal and Sr ₂ Al ₂ SiO _{7 crystal (this} The crystals are not particularly limited as long as they contain (invention crystals), and other crystal phases (that is, substituted solid solutions or penetrating solid solutions of these crystals) may be contained. Further, a crystal phase other than the crystal of the present invention may be contained within a range that does not interfere with the effect of the present invention. Such _{crystals, CaO-Al 2 O 3 -SiO} 2 based crystal (e.g. CaAl ₂ Si ₂ O ₈ crystal), CaO-SiO ₂ based crystal like can be mentioned.

The encapsulant of the present invention is obtained, for example, using the glass composition of the present invention as a starting material. When the glass composition of the present invention is used as a starting material, the encapsulant of the present invention can be obtained by firing the glass composition of the present invention.

The firing conditions are usually not particularly limited as long as the crystals of the present invention are formed. The firing temperature is usually about 1000 to 1300 ° C. In addition, the firing atmosphere may generally be the atmosphere or an oxidizing atmosphere. Moreover, the pressure may be fired under atmospheric pressure.

The encapsulant of the present invention has the same composition as the glass composition of the present invention, and the preferred range thereof can be preferably the same as that of the glass composition of the present invention. Therefore, for example, 1) SiO ₂ : 42 to 47 mol%, 2) SrO: 17 to 34 mol%, 3) ZnO: 8 to 15 mol%, 4) Al ₂ O ₃ : 4 to 15 mol% and 5) RO : A glass composition containing 0 to 5 mol% can be preferably adopted.

Thermal expansion coefficient in the present invention a sealing material (alpha value) is not particularly limited, the thermal expansion coefficient at 50 to 850 ° C. is 35~100 × ^{10 -7} / ℃, especially 40~90 × ^{10 -7} / ℃ Is more preferable, and more preferably 70 to 85 × 10 ^-7 / ° C. Controlling within such a range can further improve the sealing performance of electronic components.

Further, in the present invention, as described above, the thermal expansion characteristics of the obtained crystallized glass can be freely and surely changed by _{mainly changing the Al 2} O _{3 content within the above range.} Therefore, when it has a relatively large coefficient of thermal expansion, it can usually ^{be set in the range of 60 to 100 × 10 -7} / ° C, and in particular, it can be controlled to ^{80 to 96 × 10 -7 / ° C.} On the other hand, when it has a relatively small coefficient of thermal expansion, ^{it can be set to 35 to 65 × 10 -7} / ° C, and particularly 40 to 62 × 10 ^-7 / ° C. As described above, the glass composition of the present invention can provide a sealing material having a specific number of thermal expansion examples from a wide range of coefficient of thermal expansion.

<Embodiment>
An embodiment in the case where the semiconductor element is sealed with the sealing material of the present invention by using the glass composition of the present invention as a starting material is shown below.

Various modes can be taken as the sealing step. For example, (1) a) a step of forming a precursor layer by covering a part or all of the electronic part with the glass composition of the present invention so as to come into contact with the surface of the electronic part, b) firing the precursor layer. A method including a step of forming a sealing material layer containing crystallized glass (coating sealing method), (2) a) The glass of the present invention is formed in a contact region between a container containing an electronic component and a lid material thereof. A method including a step of forming a precursor layer by the composition, b) a step of covering the container with a lid material, and c) a step of forming a sealing material layer containing crystallized glass by firing the precursor layer (a step of forming a sealing material layer containing crystallized glass). Adhesive sealing method) and the like.

In particular, the glass composition of the present invention can be advantageously adopted in the above-mentioned coating and sealing method from the viewpoint of having, for example, good fluidity, an appropriate coefficient of thermal expansion, and the like. For example, as shown in FIG. 1, when the thermistor 10 is manufactured as an electronic device, a semiconductor element 12 to which two lead wires 13 are connected is prepared as an electronic component, and then a) the whole semiconductor element 12 and two semiconductor elements 12 are prepared. Step of forming a precursor layer by directly covering a part of the lead wire 13 of the above with the glass composition of the present invention, b) By firing the precursor layer, a sealing material layer 11 containing crystallized glass is formed. By a method including a step, the coating and sealing of the electronic component can be preferably performed. By performing the coating sealing treatment in this way, the electronic device is _{in a state where at least the entire electronic component is embedded in the SrO-SiO 2} system crystallized glass sealing material (the sealing material of the present invention described later). , Electronic components will be effectively protected from the external environment.

When sealing an electronic component using the glass composition of the present invention, the above firing temperature and the like are the firing conditions and the like described in _{the above "2. SrO-SiO 2 system crystallized glass sealing material".} It may be carried out according to.

Examples and comparative examples are shown below, and the features of the present invention will be described more specifically. However, the scope of the present invention is not limited to the examples.

Examples 1-18 and Comparative Example 1
The raw materials are mixed and mixed so as to have the glass composition shown in Tables 1 to 4, the mixed raw materials are placed in a platinum crucible and melted at 1450 to 1600 ° C. for 2 hours, and then the molten glass is melted in a stainless steel cooling roll. Glass flakes were obtained by contacting with and quenching. The glass flakes were placed in a pot mill and pulverized while adjusting the average particle size to about 5 to 10 μm. Then, coarse particles were removed with a sieve having a mesh size of 106 μm to obtain glass powders of Examples and Comparative Examples, respectively.

As the starting materials (sources of each component) for producing the glass compositions of Examples and Comparative Examples, SiO ₂ , Al (OH) ₃ , CaCO ₃ , SrCO ₃ , Mg (OH) ₂ , BaCO ₃ and ZnO were used, respectively.

Test Example 1
For the glass powders of each Example and Comparative Example, the glass transition point, softening point, crystallization start temperature, and average particle size of the glass powder were measured by the following methods. Further, the glass powder was fired in the air, and the flow diameter and the coefficient of thermal expansion of the green compact were measured and evaluated. These results are shown in Tables 1 to 4. The methods for measuring each physical property were carried out as follows.

(1) Glass transition point, softening point and crystallization start temperature
Approximately 40 mg of glass powder is filled in a platinum cell, and the temperature is raised from room temperature at 20 ° C./min using a DTA measuring device (Thermo Plus TG8120 manufactured by Rigaku Co., Ltd.) to obtain a glass transition point (Tg), a softening point (Ts), and a softening point (Ts). The crystallization start temperature (Tx) was measured.

(2) Particle size of glass powder (average particle size)
The value of D50 in the volume distribution mode was determined using a laser scattering particle size distribution meter.

(3) Airtightness
Using 5 g of glass powder, a cylindrical green compact having a diameter of 20 mm and a height of 10 to 15 mm was formed. This molded product was placed on an alumina substrate and fired at 1100 ° C. for 1 hour, and the appearance of the obtained fired product was evaluated. The evaluation criteria were "○" when flowing or when the fired body was shrinking, and "x" when not shrinking or melting.

(4) Coefficient of thermal expansion
The fired body obtained in (3) above was cut into a size of about 5 mm × 5 mm × 15 mm to prepare a test body. From the thermal expansion curve obtained when the temperature of this test piece is raised from room temperature to 10 ° C./min using a TMA measuring device, the coefficient of thermal expansion α (× ^{10-7) based on two points of 50 ° C. and 850 ° C.} / ° C) was calculated.

(5) Crystal form
The fired body obtained in (3) above was subjected to powder X-ray diffraction analysis. Based on the _results, SrZn 2 _Si 2 _{O 7 crystals,} to confirm the presence or absence of Sr ₂ ZnSi 2 O _{7 crystal,} at least one crystalline phase of SrAl 2 _Si 2 _{O 8} crystal and _Sr 2 _Al 2 SiO ₇ crystals.

As is clear from the results in Tables 1 to 4, the crystals of the present invention are expressed in the glass compositions of each example, and excellent heat resistance can be expected. In addition, since the airtightness is also good, it can be seen that excellent performance can be exhibited in terms of fluidity and the like when the glass composition of the present invention is used. It is also found that the composition of _{the SrO-SiO 2} system can be freely controlled from a low coefficient of thermal expansion to a high coefficient of thermal expansion by changing the _{Al 2} O _{3 content in particular.}

The sealing glass composition of the present invention is applied to the surfaces of a metal and a semiconductor, and can be suitably sealed between the members by firing at a temperature of, for example, about 1100 ° C. The encapsulant of the present invention is particularly useful as an encapsulant for encapsulating a temperature sensor used under high temperature conditions of, for example, 1100 ° C. or higher.

Claims (9)

A glass composition for producing a crystallized glass encapsulant containing SrO-SiO _{2 crystal, at least the following components;}
1) SiO ₂ : 41-55 mol%,
2) SrO: 17 ~40 mol%,
3) ZnO: 1 to 20 mol%,
4) Al ₂ O ₃ : 3.1 to 25 mol% and 5) RO (where R indicates at least one of Mg, Ca and Ba): 0 to 20 mol% in total.
A glass composition for sealing, which comprises. The above ingredients
1) SiO ₂ : 42-55 mol%,
2) SrO: 17 ~40 mol%,
3) ZnO: 1 to 20 mol%,
4) Al ₂ O ₃ : 3.1 to 25 mol% and 5) RO (where R indicates at least one of Mg, Ca and Ba): a total of 0 to 20 mol%, claim 1. The sealing glass composition according to the above. The above ingredients
1) SiO ₂ : 41-55 mol%,
2) SrO: 17 ~40 mol%,
3) ZnO: 1 to 20 mol%,
4) Al ₂ O ₃ : 3.1 to 25 mol% and 5) RO (where R indicates at least one of Mg, Ca and Ba): 0 to 17 mol% in total.
The sealing glass composition according to claim 1. The above ingredients
1) SiO ₂ : 41-55 mol%,
2) SrO: 17 ~40 mol%,
3) ZnO: 1 to 20 mol%,
4) Al ₂ O ₃ : 3.1 mol% or more and less than 13 mol% and 5) RO (where R indicates at least one of Mg, Ca and Ba): 0 to 20 mol% in total.
The sealing glass composition according to claim 1. The above ingredients
1) SiO ₂ : 41-55 mol%,
2) SrO: 17 ~40 mol%,
3) ZnO: 1 to 20 mol%,
4) Al ₂ O ₃ : 13 to 25 mol% and 5) RO (where R indicates at least one of Mg, Ca and Ba): 0 to 20 mol% in total.
The sealing glass composition according to claim 1. SrO-SiO ₂ system crystallized glass encapsulant
(1) At least the following components;
1) SiO ₂ : 41-55 mol%,
2) SrO: 17 ~40 mol%,
3) ZnO: 1 to 20 mol%,
4) Al ₂ O ₃ : 3.1 to 25 mol% and 5) RO (where R indicates at least one of Mg, Ca and Ba): 0 to 20 mol% in total.
Including
(2) as SrO-SiO ₂ based _crystal, comprising SrZn 2 _Si 2 _{O 7 crystals,} Sr 2 ZnSi ₂ O _{7 crystals,} at least one of SrAl 2 _Si 2 _{O 8} crystal and _Sr 2 _Al 2 SiO ₇ crystal,
A SrO-SiO ₂ system crystallized glass encapsulant characterized by this. _{The SrO-SiO 2} system crystallized glass encapsulant according to claim 5, wherein the coefficient of thermal expansion at 50 to 850 ° C. is 35 to 100 × ^{10-7 / ° C.} An electronic device in which electronic components are sealed by _{the SrO-SiO 2} system crystallized glass encapsulant according to claim 6 or 7. _{A method for producing a SrO-SiO 2-} based crystallized glass encapsulant, which comprises a step of heat-treating the encapsulating glass composition according to claim 1 at a temperature of 1000 to 1300 ° C.

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