JP2019089689A - Glass composition and sealing material - Google Patents

Abstract

To provide a glass composition that can be sealed at a low temperature without containing environmentally harmful lead and halogen, and a sealing material prepared therewith.SOLUTION: A glass composition contains, in mol%, AgO more than 0 to 50%, VOmore than 0 to 45%, TeOmore than 5-40%, AgO+VO+TeOmore than 5-less than 75%, WO0-10%, and BaO 0-10%.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a glass composition which can be hermetically sealed at a low temperature of 400 ° C. or less without containing harmful lead and halogen, and a sealing material using the same.

  Sealing materials are used for semiconductor integrated circuits, quartz oscillators, flat display devices, glass terminals for LDs, and the like.

  Since the above-mentioned sealing material is required to have chemical durability and heat resistance, a glass-based sealing material is used instead of a resin adhesive. Glass-based sealing materials are required to have mechanical strength, fluidity, weather resistance, and other properties, but for sealing electronic components mounted with heat-sensitive elements, the sealing temperature should be as low as possible. Is required. Specifically, sealing at 400 ° C. or lower is required. Therefore, lead borate glasses containing a large amount of PbO having a very large effect of lowering the melting point have been widely used as glasses satisfying the above-mentioned characteristics (see, for example, Patent Document 1).

Japanese Patent Application Laid-Open No. 63-315536 JP 6-24797 A Patent No. 4573204

In recent years, environmental problems have been pointed out for PbO contained in lead borate glasses, and it is desirable to replace lead borate glasses with glasses that do not contain PbO. Therefore, various low melting glasses have been developed as substitutes for lead borate glasses. Among them, the Bi ₂ O ₃ -B ₂ O ₃ glass described in Patent Document 2 is expected as an alternative candidate for lead borate glasses, but the sealing temperature is as high as 450 ° C. or higher, and sealing is performed at a lower temperature. It can not be used for applications that require stopping.

In Patent Document 3, although AgI-Ag 2 _O-based glass is disclosed as sealable glass at a low temperature of 400 ° C. or less, halogen has also been pointed out on environmental issues, halogen-free glass Is desired.

  In view of the above, it is an object of the present invention to provide a glass composition which can be sealed at a low temperature without containing lead and halogen harmful to the environment, and a sealing material using the same.

The glass composition of the present invention, in mol%, _Ag 2 O 0 super _~50%, V 2 _{O 5} 0 super to 45%, TeO ₂ 5 super _{~40%, Ag 2 O + V} 2 O 5 + TeO 2 5 super- less than _75%, WO 3 _0~10%, characterized in that it contains 0% BaO. Here, “Ag ₂ O + V ₂ O ₅ + TeO ₂ ” means the total content of the contents of Ag ₂ O, V ₂ O ₅ and TeO ₂ .

The glass composition of the present invention achieves low melting point by containing Ag ₂ O, V ₂ O ₅ and TeO ₂ as essential components. Generally, when the melting point of glass is lowered, it does not vitrify or phase separation occurs, and it tends to be difficult to obtain homogeneous glass, but the content of Ag ₂ O + V ₂ O ₅ + TeO ₂ is specified as less than 75%. Therefore, the glass is stabilized, and a homogeneous glass can be obtained.

The glass composition of the present invention, furthermore, in _{mol%, P 2 O 5 0~30%} , Nb 2 O 5 0~15%, 0~25% ZnO, the 2 O 0~20% Li 2 O + Na 2 O + K It is preferable to contain. Here, “Li ₂ O + Na ₂ O + K ₂ O” means the total of the contents of Li ₂ O, Na ₂ O and K ₂ O.

The glass composition of the present invention preferably further contains less than 0 to 8% of MnO ₂ + Fe ₂ O ₃ + NiO + CuO in mole%. Here, “MnO ₂ + Fe ₂ O ₃ + NiO + CuO” means the total content of the contents of MnO ₂ , Fe ₂ O ₃ , NiO and CuO.

  The glass composition of the present invention preferably contains substantially no PbO or halogen. The halogen includes halides as well as halogen, fluorine, chlorine, bromine and iodine. The halides are fluorides, chlorides, bromides and iodides. Here, "substantially free of PbO and halogen" in the present invention refers to the case where the content of each of PbO and halogen in the glass composition is 1000 ppm or less.

  The sealing material of the present invention is characterized by containing 50 to 100% by volume of a glass powder comprising the above glass composition and 0 to 50% by volume of a refractory filler powder.

  It is possible to provide a glass composition that can be sealed at a low temperature and a sealing material using the same without containing environmentally harmful lead and halogen.

It is a schematic diagram which shows the measurement curve obtained by a macro-type differential thermal analyzer.

The glass composition of the present invention, in mol%, _Ag 2 O 0 super _~50%, V 2 _{O 5} 0 super to 45%, TeO ₂ 5 super _{~40%, Ag 2 O + V} 2 O 5 + TeO 2 5 super- It contains less than 75%, WO ₃ 0-10%, BaO 0-10%. The reasons for limiting the glass composition as described above are as follows. In the following description regarding the content of each component, “%” means “mol%” unless otherwise noted.

Ag ₂ O is a component that lowers the softening point. The content of Ag ₂ O is more than 0 to 50%, preferably 10 to 40%, particularly 20 to 35%. When the content of Ag ₂ O is too small, the softening point becomes high, and low temperature sealing tends to be difficult. On the other hand, when the content of Ag ₂ O is too large, the glass becomes thermally unstable, and the glass tends to be devitrified at the time of melting or firing.

V ₂ O ₅ is a component that forms a glass network and lowers the softening point. The content of V ₂ O ₅ is more than 0 to 45%, preferably 0.5 to 40%, 5 to 35%, 5 to 33%, particularly 5 to 30%. When the content of V ₂ O ₅ is too small, the softening point becomes high, and low temperature sealing tends to be difficult. On the other hand, when the content of V ₂ O ₅ is too large, the glass becomes thermally unstable, and the glass tends to be devitrified at the time of melting or firing, and the water resistance tends to be reduced.

TeO ₂ is a component that improves the water resistance as well as forming a glass network. The content of TeO ₂ is more than 5 to 40%, preferably 7 to 35%, particularly 10 to 30%. If the content of TeO ₂ is too low, the water resistance tends to be reduced. On the other hand, when the content of TeO ₂ is too large, the glass becomes thermally unstable, and the glass tends to be devitrified at the time of melting or firing, and the fluidity tends to be reduced.

The content of Ag ₂ O + V ₂ O ₅ + TeO ₂ is preferably more than 5 and less than 75%, preferably 10 to 74%, particularly 25 to 73%. When the content of Ag ₂ O + V ₂ O ₅ + TeO ₂ is too small, the softening point becomes high, and low temperature sealing tends to be difficult. On the other hand, when the content of Ag ₂ O + V ₂ O ₅ + TeO ₂ is too large, the glass becomes thermally unstable, and the glass tends to be devitrified at the time of melting or firing.

WO ₃ is a component that stabilizes the glass thermally and improves water resistance. The content of WO ₃ is 0 to 10%, preferably 0 to 8%, 0 to 6%, 0 to 4%, particularly 0 to 3%. _{On the} other hand, when the content of WO ₃ is too large, the glass becomes thermally unstable, and the glass tends to be devitrified at the time of melting or firing.

  BaO is a component that thermally stabilizes the glass and improves water resistance. The content of BaO is 0 to 10%, preferably 0 to 8%, particularly 0 to 6%. When the content of BaO is too large, the viscosity (softening point etc.) of the glass becomes high, and low temperature sealing tends to be difficult.

  The glass composition of the present invention may contain the following components in the glass composition, in addition to the above components.

P ₂ O ₅ is a component that forms a glass network and thermally stabilizes the glass. The content of P ₂ O ₅ is preferably 0 to 30%, 3 to 29%, 5 to 28%, 6 to 25%, 8 to 24%, 9 to 23%, particularly 10 to 22%. When the content of P ₂ O ₅ is too large, the viscosity (softening point etc.) of the glass becomes high, and low temperature sealing becomes difficult and the water resistance tends to be lowered.

Nb ₂ O ₅ is a component that stabilizes the glass thermally and improves water resistance. The content of Nb ₂ O ₅ is preferably 0 to 15%, 0 to 12%, particularly 0 to 10%. When the content of Nb ₂ O ₅ is too large, the viscosity (softening point etc.) of the glass becomes high, and low temperature sealing tends to be difficult.

  ZnO is a component that improves the water resistance as well as lowering the softening point. The content of ZnO is preferably 0 to 25%, 0 to 22%, 0 to 18%, particularly 0 to 16%. When the content of ZnO is too large, the glass becomes thermally unstable and the glass tends to be devitrified at the time of melting or firing.

Li ₂ O, Na ₂ O and K ₂ O have the effect of lowering the softening point, and their total content is preferably 0 to 20%, particularly 0 to 10%. When the content is too large, the glass becomes thermally unstable, and the glass tends to be devitrified at the time of melting or firing and the water resistance tends to be reduced. _{Incidentally, Li 2 O, Na 2 O} , K 2 O , respectively content of 0-10%, particularly preferably 0 to 5%.

  MgO is a component that stabilizes the glass thermally and improves water resistance. The content of MgO is preferably 0 to 10%, 0 to 5%, particularly 0 to 3%. When the content of MgO is too large, the glass becomes thermally unstable and the glass tends to be devitrified at the time of melting or firing.

  CaO is a component that thermally stabilizes the glass and improves water resistance. The content of CaO is preferably 0 to 10%, 0 to 5%, particularly 0 to 3%. When the content of CaO is too large, the glass becomes thermally unstable and the glass tends to be devitrified at the time of melting or firing.

  SrO is a component that thermally stabilizes the glass and improves water resistance. The content of SrO is preferably 0 to 10%, 0 to 5%, particularly 0 to 3%. When the content of SrO is too large, the glass becomes thermally unstable and the glass tends to be devitrified at the time of melting or firing.

Ga ₂ O ₃ is a component that thermally stabilizes the glass and improves water resistance, but because it is very expensive, its content is preferably less than 0.01%, and particularly preferably not contained. .

MnO ₂ , Fe ₂ O ₃ , NiO, and CuO are components that thermally stabilize the glass to suppress devitrification, and can be added to less than 2% each. When the content is too large, the glass becomes thermally unstable, and the glass tends to be devitrified at the time of melting or firing. In addition, MnO ₂ + Fe ₂ O ₃ + NiO + CuO (total amount of contents of MnO ₂ , Fe ₂ O ₃ , NiO and CuO) is 0 to less than 8%, 0 to 5%, or less than 0 to 2% preferable.

In addition to the above components, other components such as SiO ₂ , B ₂ O ₃ , Al ₂ O ₃ and Bi ₂ O ₃ may be added to the glass composition to a total amount of 10%. However, as described above, it is preferable not to substantially contain PbO and halogen.

  The sealing material of the present invention may contain a refractory filler in the glass powder comprising the above glass composition in order to improve the mechanical strength or adjust the thermal expansion coefficient. The mixing ratio is 50 to 100% by volume of glass powder, 0 to 50% by volume of refractory filler, 70 to 99% by volume of glass powder, 1 to 30% by volume of refractory filler, particularly 80 to 95% by volume of glass powder, The refractory filler is preferably 5 to 20% by volume. If the content of the refractory filler is too large, the proportion of the glass powder relatively decreases, and it becomes difficult to secure desired fluidity.

  The refractory filler is not particularly limited, and various materials can be selected. However, those refractory to the above-described glass powder are preferable.

Specifically, as the refractory _{filler, NbZr (PO 4) 3,} Zr 2 WO 4 (PO 4) 2, Zr 2 MoO 4 (PO 4) 2, Hf 2 WO 4 (PO 4) 2, Hf 2 MoO ₄ (PO ₄ ) ₂ , zirconium phosphate, zircon, zirconia, tin oxide, aluminum titanate, quartz, β-spodumene, mullite, titania, quartz glass, β-eucryptite, β-quartz, willemite, cordierite the _{Sr 0.5 Zr 2 (PO 4)} 3 NaZr such _{2 (PO 4) 3} type solid solution, can be used alone or in combination of two or more. In addition, as for the particle size of the refractory filler, it is preferable to use one having an average particle size D ₅₀ of about 0.2 to ₂₀ μm.

The softening point of the glass composition and the sealing material of the present invention is preferably 400 ° C. or less, 390 ° C. or less, 380 ° C. or less, particularly preferably 370 ° C. or less. If the softening point is too high, the viscosity of the glass becomes high, so the sealing temperature rises, and there is a possibility that the element may be damaged at the time of sealing. The lower limit of the softening point is not particularly limited, but is practically 180 ° C. or more. Here, the "softening point" refers to a value measured by a macroscopic differential thermal analyzer using a glass composition having an average particle diameter D50 of _0.5 to 20 m and a sealing material as a measurement sample. As measurement conditions, measurement is started from room temperature, and the temperature rising rate is 10 ° C./min. The softening point measured by the macroscopic differential thermal analyzer indicates the temperature (Ts) at the fourth inflection point in the measurement curve shown in FIG.

The thermal expansion coefficient (30 to 150 ° C.) of the glass composition and the sealing material of the present invention is 190 × 10 ⁻⁷ / ° C. or less, 180 × 10 ⁻⁷ / ° C. or less, in particular 170 × 10 ⁻⁷ / ° C. or less Is preferred. When the thermal expansion coefficient is too high, the sealing portion is easily damaged during sealing or after sealing due to the expansion difference with the sealing material. Although the lower limit of the thermal expansion coefficient is not particularly limited, it is practically 50 × 10 ⁻⁷ / ° C. or more.

  Next, a method for producing a glass powder using the glass composition of the present invention, and an example of a method of using the glass composition of the present invention as a sealing material will be described.

First, the raw material powder prepared so as to have the above composition is melted at 800 to 1000 ° C. for 1 to 2 hours until a homogeneous glass is obtained. Next, the molten glass is formed into a film or the like, and then crushed and classified to prepare a glass powder comprising the glass composition of the present invention. Incidentally, it is preferable that the average particle diameter _{D 50} of the glass powder is about 2 to 20 [mu] m. If necessary, various refractory filler powders are added to the glass powder.

  Next, a vehicle is added to glass powder (or mixed powder of glass powder and refractory filler powder) and kneaded to prepare a glass paste. The vehicle mainly consists of an organic solvent and a resin, and the resin is added for the purpose of adjusting the viscosity of the paste. Moreover, surfactant, a thickener, etc. can also be added as needed.

The organic solvent preferably has a low boiling point (e.g., a boiling point of 300 [deg.] C. or less) and a small amount of residue after firing, and preferably does not denature the glass, and its content is 10 to 40% by mass preferable. Examples of the organic solvent include propylene carbonate, toluene, N, N'-dimethylformamide (DMF), 1,3-dimethyl-2-imidazolidinone (DMI), dimethyl carbonate, butyl carbitol acetate (BCA), isoamyl acetate, It is preferable to use dimethyl sulfoxide, acetone, methyl ethyl ketone and the like. Further, it is more preferable to use a higher alcohol as the organic solvent. Higher alcohols can be pasted without the addition of resin to the vehicle because they are themselves viscous. In addition, pentanediol and a derivative thereof, specifically, diethylpentanediol (C ₉ H ₂₀ O ₂ ) can also be used as a solvent since the viscosity is excellent.

In addition to having a low decomposition temperature and a small amount of residue after firing, the resin is preferably one that is difficult to deteriorate glass, and the content thereof is preferably 0.1 to 20% by mass. It is preferable to use nitrocellulose, a polyethylene glycol derivative, polyethylene carbonate, an acrylic ester (acrylic resin) etc. as resin.

  Then, using a dispenser such as a dispenser or a screen printing machine at the sealing position of the paste between the first member made of metal, ceramic or glass and the second member made of metal, ceramic or glass It is applied, dried and heat treated at 350-400 ° C. By this heat treatment, the glass powder softens and flows to seal the first and second members.

  The glass composition and the sealing material of the present invention can be used for the purpose of coating, filling, etc. besides sealing. Moreover, it can also be used in forms other than a paste, specifically, powder, a green sheet, a tablet, etc. state.

  The invention will be described in detail on the basis of examples. Tables 1-3 have shown the Example (sample No. 1-12) and comparative example (sample No. 13-16) of this invention.

First, glass raw materials such as various oxides and carbonates are prepared so as to obtain the glass composition shown in the table, and a glass batch is prepared, then this glass batch is put in a platinum crucible and 1 to 800 ° C. to 1000 ° C. It melted for 2 hours. Next, a part of the molten glass was poured out into a stainless steel mold as a sample for TMA (pushing rod type thermal expansion coefficient measurement), and the other molten glass was formed into a film by a water cooling roller. In addition, the No. 1 which does not contain a refractory filler. Samples 2 to 4, 6 to 8 and 12 to 16 were subjected to a predetermined annealing treatment (annealing) after forming to obtain a TMA sample. Finally, the film-like glass was crushed by a ball mill, and then passed through a sieve with an opening of 75 μm to obtain a glass powder having an average particle diameter D ₅₀ of about 10 μm.

  After that, No. 1 which mixes fireproof filler. For the samples 1, 5, 9 to 11, the obtained glass powder and the refractory filler powder were mixed as shown in the table to obtain a mixed powder.

For the refractory filler powder, NbZr (PO ₄ ) ₃ (referred to as NZP in the table) and Zr ₂ WO ₄ (PO ₄ ) ₂ (referred to as ZWP in the table) were used. The average particle diameter _{D 50} of the refractory filler powder was about 10 [mu] m.

  The obtained mixed powder was fired at 380 ° C. for 10 minutes to obtain a fired body. The obtained fired body was used as a sample for TMA.

  No. The glass transition point, the thermal expansion coefficient, the softening point, the flowability and the devitrification resistance were evaluated for the samples 1 to 16.

  The glass transition point and the thermal expansion coefficient (30 to 150 ° C.) were measured with a TMA apparatus for a sample for TMA.

  The softening point was measured by a macroscopic differential thermal analyzer. The measurement atmosphere was air, the temperature rising rate was 10 ° C./min, and the measurement was started from room temperature.

  The liquidity was assessed as follows. 1 g of the powder sample was put into a die with a diameter of 10 mm and press-formed, and then it was fired at 380 ° C. for 10 minutes on a stainless steel plate. The sintered body having a flow diameter of 10 mm or more was evaluated as “◎”, and those smaller than 9 to 10 mm were evaluated as “o”, those smaller than 9 mm as “x”.

  The devitrification resistance was evaluated as follows. The surface state of the sintered body was observed using an optical microscope (magnification: 100 ×). Evaluations were made as “○” where no crystals were found on the surface of the fired body, and as “×” when crystals were found on the surface of the fired body.

As is apparent from the table, the Nos. 1 and 2 which are examples of the present invention. Samples 1 to 12 were excellent in flowability and devitrification resistance. On the other hand, No. 1 as a comparative example. The 13 samples did not vitrify because they contained an excess of V ₂ O ₅ . No. Sample No. 14 contained TeO ₂ in excess, and thus was inferior in flowability and devitrification resistance. No. Fifteen samples did not vitrify because they contained Ag ₂ O in excess. No. 16 samples are because it is contained excessively WO _3, were not vitrified.

  The glass composition and the sealing material of the present invention are suitable for sealing a semiconductor integrated circuit, a quartz oscillator, a flat display device, and a glass terminal for LD.

Claims (5)

In mole%, _Ag 2 O 0 super _~50%, V 2 _{O 5} 0 super to 45%, TeO ₂ 5 super _{~40%, Ag 2 O + V} 2 O 5 + TeO less than ₂ 5 super ~75%, _WO 3 0~ A glass composition comprising 10% and 0 to 10% of BaO. Furthermore, in _{mol%, P 2 O 5 0~30%} , Nb 2 O 5 0~15%, 0~25% ZnO, claims, characterized in that it contains 2 O 0~20% Li 2 O + Na 2 O + K Item 6. The glass composition according to item 1. The glass composition according to claim 1 or 2, further comprising less than 0 to 8% of MnO ₂ + Fe ₂ O ₃ + NiO + CuO in mol%.   The glass composition according to any one of claims 1 to 3, which is substantially free of PbO and halogen.   A sealing material comprising 50 to 100% by volume of a glass powder comprising the glass composition according to any one of claims 1 to 4 and 0 to 50% by volume of a refractory filler powder.