JP3534257B2 - Sealing material - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sealing material,
Electronic components such as IC packages and display devices.
The present invention relates to a sealing material to be attached . 2. Description of the Related Art Conventionally, as a sealing material for sealing electronic components such as IC packages and display devices, a filler powder has been used together with a low-melting glass powder for adjusting a thermal expansion coefficient and the like. You. [0003] As one of the methods for producing the filler powder, a method called a crystallized glass method is generally known. The crystallized glass method is a method in which a glass material prepared to have a desired chemical composition is first melted, molded and pulverized to produce a crystalline glass powder, and then fired and crystallized. , Willemite, β-quartz solid solution, cordierite, β-eucryptite, zinc petalite, garnite, and the like. [0004] However, in the above-mentioned method, in the firing step of the crystalline glass powder, these are fused to each other and strongly squeezed to form a hard crystal mass. There is a drawback that re-grinding is required, and the production cost is high. In the re-grinding process, fine powder of crystals having a particle size of 0.5 μm or less is generated. However, if the powder is classified to remove the fine powder, the yield of the filler powder is reduced and the cost becomes extremely high. Not preferred. Therefore, it is usually mixed with the low-melting glass powder while containing the fine powder. However, when such fine powder is present in the sealing material, the specific surface area of the filler increases (that is, the reaction area with the glass increases, and the filler easily melts into the low-melting glass). There is a problem that it will be done. An object of the present invention is to provide a sealing material which can be manufactured at low cost and which does not impair the fluidity . As a result of various experiments, the present inventors have found that, when producing filler powder , if the crystallized glass powder can be prevented from contacting each other during firing, the It has been found that crystallization can be performed in the same state as described above, and re-grinding becomes unnecessary, and the present invention has been proposed. That is, the sealing material of the present invention is a low melting glass
A sealing material comprising a powder and a filler powder;
Ra powder, adding a refractory material powder into crystalline glass powder were mixed, and crystallizable glass powder without熔着crystallizable glass powder and the refractory material powder is at a temperature sufficient to crystallize It is characterized by being manufactured by a firing method.
Sign. The filler powder used in the sealing material of the present invention is produced.
To manufacture , first, a refractory substance powder is added to the crystalline glass powder. The amount of the refractory substance powder to be added is preferably at least 0.1 part by weight, more preferably 1 to 70 parts by weight, based on 100 parts by weight of the crystalline glass powder. If the amount of the refractory substance powder is less than 0.1 part by weight, the effect of preventing the contact between the crystalline glass powders is almost lost. The crystalline glass powder to be used is produced by melting a glass material prepared to have a desired chemical composition, and then molding and pulverizing it. If so, it is possible to use those having various compositions. Such as, for example, willemite, β-quartz solid solution, cordierite, β-eucryptite, zinc petalite,
Crystalline substances such as garnite can be used. Note that the composition of the crystalline glass may slightly deviate from the theoretical composition value of these crystals. It is desirable to use crystalline glass powder having a particle size of 45 μm or less. The refractory substance powder is mixed to prevent contact between the crystalline glass powders. The refractory substance powder has a melting point equal to or higher than that of a crystalline product obtained by firing the crystalline glass powder and has a high melting point. Use a material that does not easily react with the functional glass. Such materials include, in particular, willemite ceramics, zircon ceramics, tin oxide ceramics, zirconia, alumina, cordierite, titanium oxide, silica, β-quartz solid solution,
β-eucryptite, zinc petalite, and garnite are preferable, and other than these, crystal powder such as lead titanate-based ceramics, mullite-based ceramics, niobium oxide, and cristobalite can be used. It is desirable to use a refractory substance powder having a particle size of 45 μm or less. Subsequently, the crystalline glass powder and the refractory material powder are uniformly mixed. When pulverizing the crystalline glass powder,
Refractory substance powder may be added and mixed and pulverized by a ball mill or the like. Thereafter, the mixed powder is fired at a temperature sufficient for the crystalline glass powder and the refractory substance powder not to be fused and for the crystalline glass powder to crystallize. When firing is performed under such conditions, contact between the crystalline glass powders is hindered by the presence of the refractory material powder, and each crystalline glass powder is crystallized in a powder state. The mixture of the crystalline powder and the refractory powder thus obtained can be used as a filler powder for a sealing material as it is because the powders are not welded to each other. Glass fine powder generated in the pulverizing step when preparing the crystalline glass powder may be mixed into the mixed powder, but such fine powder is a crystalline glass having a large particle diameter in the process of firing the mixed powder. Since the powder is welded to the powder surface, there is almost no fine powder in the obtained filler powder. [0014] It is practically difficult to separate the filler powder obtained by the above method into a crystal of crystalline glass powder and a refractory substance powder. Therefore, when it is desired to obtain a filler powder made of a single material, it is necessary to use a refractory substance powder having the same crystal phase as the crystalline glass powder. Next, the sealing material of the present invention using the filler powder obtained by the above method will be described. The sealing material of the present invention comprises a low-melting glass powder and the filler powder produced as described above. The ratio of both is low melting glass powder: filler powder is volume%
Is preferably in the range of 45:55 to 95: 5. As the low-melting glass powder, those having a glass transition point of 350 ° C. or lower are preferably used, and such powders include PbO—B ₂ O ₃ and PbO—Bi.
₂ O ₃ —Fe ₂ O ₃ system, PbO—Bi ₂ O ₃ —CuO
System, PbO-B ₂ O ₃ -ZnO-based, PbO-B ₂ O ₃ -
Bi ₂ O ₃ system, it is possible to use an amorphous or crystalline glass PbO-V ₂ O ₅ system and the like. [0018] In addition to the filler powder produced as described above, the same or different filler powder produced by a usual method may be added to the sealing material of the present invention, if necessary. Such filler powders include, for example, willemite ceramics, zircon ceramics,
Tin oxide ceramics, lead titanate ceramics, zirconia, alumina, cordierite, mullite ceramics, niobium oxide, β-eucryptite, titanium oxide, silica, garnite, quartz glass, cristobalite, etc. can be used. . Hereinafter, the present invention will be described with reference to examples. Tables 1 and 2 show the sealing materials used in the examples.
Filler powder (samples A to H) and sealing used in comparative examples
3 shows a filler powder for a dressing material (sample I) . [Table 1] [Table 2] First, pure silica powder, aluminum oxide, zinc oxide, zirconia, titanium oxide, lithium oxide, magnesium oxide, and aluminum phosphate are prepared and mixed so that the composition shown in the table may be obtained, and the mixture is placed in a platinum crucible. 1500-
Melted at 1650 ° C. for 3 hours. Next, the molten glass was formed into a plate shape, pulverized, and passed through a 350-mesh stainless steel sieve to obtain a crystalline glass powder having a particle size of 45 μm or less. Next, refractory material powders were added at the ratios shown in the table, mixed, and fired under the firing conditions shown in the table.
Sample I was fired without adding the refractory substance powder. When the fired product thus obtained was used as a filler powder for a sealing material, it was examined whether crushing or pulverization was necessary. Samples A to H prepared by the above method were used. It was found that neither crushing nor pulverization was required, and that the product could be used as it was. On the other hand, Sample I was a hard lump crystal which was hardened firmly and thus could not be disintegrated, and a filler powder equivalent to that of Sample H could not be obtained unless re-ground by a ball mill. For the samples A to H before firing (crystalline glass powder) and after firing (filler powder), the specific surface area was measured by a fluid specific surface area measuring device, and the average particle size was measured by a Microtrac particle size analyzer. As a result, the average particle size (D
Despite little change was not in ₅₀ value), the specific surface area was greatly reduced after firing. On the other hand, for the sample I, the specific surface area and the average particle size were measured after the re-grinding. As a result, the average particle size ₍₅₀ value D) although was comparable to Example, the specific surface area was greater than the value of each example after calcination. From these facts, the filler powders of Samples A to H are:
It can be inferred that the specific surface area was reduced because the fine powder was fused to the surface of the crystalline glass powder during firing. In order to confirm the presence or absence of welding of the fine powder,
After the filler powders of Samples A to H were each kneaded and cured with a resin, the cross section of the cured product was polished and observed with an electron microscope. As a result, fine powder was welded to the surface of the filler powder for each sample. Was recognized. The filler powder thus obtained shows that sample A has β
A mixture of a quartz solid solution powder and a zircon-based ceramic powder, a sample B is a mixture of a β-quartz solid solution powder and a willemite-based ceramic powder, a sample C is a mixture of a cordierite powder and a zirconia powder, and a sample D is a β.
-A mixture of eucryptite powder and tin oxide-based ceramic powder, sample E is a mixture of zinc petalite powder and cordierite powder, sample F is a mixture of ganite powder, zirconia powder and titanium oxide powder, and sample G is willemite. Each of the mixture composed of the ceramic powder, the alumina powder, and the silica powder, Sample H, and Sample I was a willemite ceramic powder. Next, a sealing material was prepared using the obtained filler powders of Samples A to I. Table 3 shows the low melting point glass powder (sample a)
To c). Tables 4 and 5 show Examples (Sample Nos. 1 to 9) and Comparative Examples (Sample No. 10) of the sealing material of the present invention produced using the filler powder. [Table 3] [Table 4] [Table 5] The low melting point glass shown in Table 3 was prepared as follows. First, Komeitan was prepared so as to have the composition shown in Table 3.
Bismuth oxide, iron oxide, boric acid, zinc white, pure silica powder, aluminum oxide, and barium carbonate were mixed and mixed, and the mixture was put in a platinum crucible and melted at 900 ° C. for 1 hour. Next, the molten glass was formed into a plate shape, pulverized, and passed through a 350-mesh stainless steel sieve to obtain a low-melting glass powder having a particle size of 45 μm or less. Samples a to c obtained in this manner have a glass transition point of 290 to 300 ° C., 3
The coefficient of thermal expansion at 0 to 250 ° C. is 108 to 115 × 1
0 ^-7 / ° C. Subsequently, low melting glass powder and filler powder were mixed at the ratios shown in Tables 4 and 5 to prepare a sealing material. When the sealing material, the thermal expansion coefficient, the transverse rupture strength, the insulation resistance and the fluidity of the sealing material thus produced were evaluated, Sample Nos. Using the fillers of Samples A to H were evaluated. The sealing materials 1 to 9 have a sealing temperature of 390 to 4
Coefficient of thermal expansion at 00 ° C and 30-250 ° C is 50-7
5 × 10 ^-7 / ° C, flexural strength 550-650 kg / cm
^2. Insulation resistance at 150 ° C is 13.2-14.2Ω · c
m, and the fluidity was good. On the other hand, the sample No. 10 is 30-
The coefficient of thermal expansion at 250 ° C. is 68 × 10 ⁻⁷ / ° C., the flexural strength is 600 kg / cm ² , and the insulation resistance at 150 ° C. is 1
Although it was 3.3 Ω · cm, which was the same value as each of the samples of the examples, the sealing temperature and the fluidity were the same for sample No. It was worse than 9. This is presumably because the fine powder contained in the filler powder of Sample H adversely affected the fluidity. It is to be noted that the necessity of crushing when preparing the filler powder is required when the average particle diameter of the fired product is at least 2 μm larger than that of the mixed powder before firing.
If it was less than μm, it was unnecessary. Regarding the necessity of pulverization, when there was a lump having a particle diameter of 1 mm or more that could not be crushed when crushed with one hand using a spoon, the necessity of crushing was determined to be necessary. The glass transition point and the coefficient of thermal expansion were measured using a push rod type thermal expansion measuring device. The flexural strength was measured by forming each sample into a prism having a size of 10 × 10 × 50 mm, firing, and then measuring by a three-point load measurement method. The insulation resistance was measured using a mega-ohm meter. In addition, the fluidity was measured by using a cylinder with an outer diameter of 20 mm and a height of 5 mm produced from each sample.
After heating and flowing at 00 ° C. for 10 minutes, the flow diameter is 21
mm less than 21 mm
Those exceeding 2 mm were regarded as good. Crystals used as refractory material powder and other filler powder were prepared as follows. The willemite-based ceramics i consist of zinc oxide, optical stone powder and aluminum oxide in a weight ratio of ZnO70.
%, SiO ₂ 25%, and Al ₂ O ₃ 5%. After mixing, the mixture was baked at 1440 ° C. for 15 hours, pulverized, and passed through a 350 mesh stainless steel sieve, with a particle size of 45 μm. The following powders were used: The willemite-based ceramics ii is obtained by preliminarily mixing the crystalline glass powder used for the sample H at 1200 ° C.
After calcination for a period of time, the powder was pulverized and passed through a 350 mesh stainless sieve. The zircon-based ceramics are obtained by first decomposing natural zircon sand once with soda, dissolving it in hydrochloric acid, and repeating concentration crystallization to obtain zirconium oxychloride having a very small amount of U and Th, which are α-ray emitting substances.
Next, after neutralization with alkali, heating was performed to obtain purified ZrO ₂ .
Then, high-purity silica powder and ferric oxide were added to this in a weight ratio of Zr.
The mixture was prepared so as to have a composition of 66% O ₂ , 32% SiO ₂ , and ₂ % Fe ₂ O _3. After mixing, the mixture was baked at 1400 ° C. for 16 hours, further pulverized, and passed through a 350 mesh stainless steel sieve. Was used. Tin oxide ceramics are composed of SnO in weight ratio.
_{2 93%, TiO 2 2%} , formulated tin oxide to be MnO ₂ 5% of the composition, titanium oxide, manganese dioxide, after mixing, was calcined for 16 hours at 1400 ° C., then ground, 3
What passed through a 50 mesh stainless steel sieve was used. Lead titanate-based ceramics include litharge,
70% PbO by weight ratio of titanium oxide and calcium carbonate,
A mixture was prepared so as to have a composition of TiO 20% and CaO 10%, and after mixing, calcined at 1100 ° C. for 5 hours. Then, the calcined product was pulverized and passed through a 350 mesh stainless steel sieve. As zirconia, alumina, cordierite, titanium oxide and silica, commercial products having a 350 mesh pass were used. As described above, the present invention is used in the present invention.
Since the filler powder does not require re-crushing after firing, it can be manufactured at a lower cost than before . Further, since the specific surface area is small, the fluidity of the sealing material is not impaired . Therefore, such filler powder
Is suitable as a sealing material .

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int. Cl. ⁷ , DB name) C03C 1/00-14/00

Claims (1)

(57) [Claims] [Claim 1] A low melting glass powder and a filler powder.
A sealing material, wherein the filler powder is obtained by adding a refractory substance powder to a crystalline glass powder and mixing, and then the crystalline glass powder and the refractory substance powder are not fused and the crystalline glass powder is to a method of firing at a temperature sufficient to crystallize
A sealing material characterized by being manufactured by the following method.