JP2011246330A - Glass ceramic composition, substrate for light emitting diode element, and light emitting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a substrate for mounting a light emitting element, which yields a light emitting device that shows little loss of light supplied from the light emitting element, is capable of increasing light use efficiency, is excellent in flatness of a surface onto which the light emitting element is mounted and shows a small thermal resistance.SOLUTION: A glass ceramic substrate comprises 25-50 mass% glass powder, 30-60 mass% alumina powder and 10-40 mass% zirconia powder, wherein the glass powder comprises 50-65 mol% SiO, 10-18 mol% BO, 9-23 mol% at least one chosen from CaO, SrO and BaO in total, 3-13 mol% AlO, 0.5-6 mol% at least one chosen from NaO and KO in total and 8-23 mol% at least one chosen from AlO, SrO and BaO in total.

Description

  The present invention relates to a glass ceramic composition, a substrate for a light emitting diode element, and a light emitting device, and more particularly, a glass ceramic composition used for manufacturing a substrate on which a light emitting diode element is mounted, and a light emitting diode element comprising the glass ceramic composition. The present invention relates to a substrate and a light emitting device.

  2. Description of the Related Art In recent years, light emitting devices using LED elements are used for backlights or general illumination of mobile phones, large liquid crystal TVs, and the like, as light emitting diode (hereinafter referred to as LED) elements increase in brightness and efficiency. It is like that. Along with this, members with higher performance are required for members around the LED element. For example, a substrate made of a resin material is used as a substrate for mounting the LED element, but is easily deteriorated by heat and light accompanying the increase in brightness of the LED element, and is made of an inorganic material such as ceramics. The use of things is being considered.

  Examples of the ceramic substrate include an alumina substrate and an aluminum nitride substrate used for a wiring substrate. Ceramic substrates are promising as LED element mounting substrates because they have higher durability against heat and light than resin substrates. However, since the ceramic substrate has a lower reflectance than that of the resin substrate, there is a problem that light from the LED element leaks to the rear of the substrate and the luminous intensity of the front is lowered. In addition, since the ceramic substrate is generally difficult to sinter, high temperature firing exceeding 1500 ° C. is required, and there is a problem that the process cost increases.

  In order to solve such a problem, use of a low-temperature co-fired ceramic (hereinafter sometimes referred to as LTCC) substrate has been studied. The LTCC substrate is generally composed of a composite of glass and a ceramic filler such as alumina, and is sintered at about 850 to 900 ° C., which is lower than that of conventional ceramics, in order to sinter due to the low temperature fluidity of the glass. Can do. Thereby, it can sinter simultaneously with the Ag conductor which is a wiring conductor, and can reduce cost compared with the conventional ceramic substrate. In addition, since light is diffusely reflected at the interface between the glass and the ceramic filler, a higher reflectance than that of the alumina substrate or the aluminum nitride substrate can be obtained. Furthermore, since it consists of an inorganic substance, sufficient durability with respect to heat and light can be obtained.

  Conventionally, in order to increase the reflectance of the LTCC substrate, a method of incorporating a ceramic filler (high refractive index filler) having a refractive index higher than that of alumina has been studied. And the LTCC board | substrate which mix | blended high refractive index fillers, such as a zirconia powder, with an alumina powder with respect to Si-B-Al-Ca type glass, and improved the reflectance is proposed (for example, patent document 1). reference). Since a high refractive index filler such as zirconia powder has a larger refractive index difference from glass than alumina powder, the diffuse reflection at the glass-ceramic interface becomes larger, resulting in improved substrate reflectivity. In the LTCC substrate of Patent Document 1, by adjusting the glass composition, the decrease in the bending strength is prevented by compensating for the decrease in sinterability due to the blending of the high refractive index filler, and the acid resistance is also improved. Yes.

WO2009 / 128354 A1

  However, when the zirconia powder is blended with the glass powder, a so-called phase separation in which the glass component in the powder is separated in an amorphous state is likely to occur during firing. The LTCC substrate using such glass powder has a problem that defects such as warpage of the substrate are likely to occur. This is because the phase separation proceeds non-uniformly due to the influence of the temperature distribution in the baking furnace during firing, and the degree of progress of sintering becomes non-uniform. In addition, since the degree of progress of sintering becomes non-uniform, the shrinkage rate of the substrate becomes non-uniform as a whole, the shape of the substrate is distorted, and the desired shape and dimensional accuracy may not be obtained.

  The present invention has been made in order to solve the above-described problems, and the phase separation of the glass powder during firing is suppressed, the warpage is small, the shape stability is good, and the reflectance is sufficient. It aims at providing the glass-ceramics composition from which a bonded body is obtained.

That is, the glass ceramic composition of the present invention comprises 25 to 50% by weight glass powder, 30 to 60% by weight alumina powder, and 10 to 40% by weight zirconia powder, said glass powder is a SiO ₂ or 50 mol% 65 mol% or _less, B 2 _{O 3} of 10 mol% or more 18 mol% or less, CaO, 1 or two or more sum of the following 9 mol% or more 23 mol% selected from SrO and BaO Al ₂ O ₃ is contained in an amount of 3 mol% or more and 13 mol% or less, and one or two selected from Na ₂ O and K ₂ O are added in a total amount of 0.5 mol% or more and 6 mol% or less. Al ₂ O ₃ , SrO and BaO 1 type or 2 types or more chosen from among 8 mol% or more and 23 mol% or less are contained in total.

In the glass ceramic composition of the present invention, the glass powder, the SiO ₂ more than 50 mol% 65 mol% or _less, B 2 _{O 3} less 10 mol% or more 18 mol%, CaO, 1 or more species selected from SrO and BaO 9 mol% or more and 23 mol% or less, Al ₂ O ₃ greater than 8 mol% and 13 mol% or less, and one or two selected from Na ₂ O and K ₂ O in total containing 0.5 mol% or more and 6 mol% or less In addition, one or two or more selected from Al ₂ O ₃ , SrO, and BaO can be contained in a total amount of 8 mol% or more and 23 mol% or less.
Further, the glass powder, the SiO ₂ more than 50 mol% 65 mol% or _less, B 2 _{O 3} of 10 mol% or more 18 mol% or less, 0 mol% to less than 9 mol% of CaO, the one or two elements selected from SrO and BaO total 3 mol% or more 23 mol% or less, _Al 2 _{O 3} of 3 mol% or more 8 mol% or less, and contains one or 0.5 mol% or more 6 mol% of two or a total of less selected from Na ₂ O and _{K 2} O, One or more selected from Al ₂ O ₃ , SrO and BaO may be contained in a total amount of 8 mol% or more and 23 mol% or less. Furthermore, in the glass ceramic composition of the present invention, the zirconia powder is preferably composed of stabilized zirconia or partially stabilized zirconia.

  The substrate for a light emitting diode element of the present invention is a substrate for mounting a light emitting diode element, and is characterized by being formed and fired from the glass ceramic composition of the present invention described above.

  The light-emitting device of the present invention is a light-emitting device comprising a light-emitting diode element substrate and a light-emitting diode element mounted on the light-emitting diode element substrate, wherein the light-emitting diode element substrate is as described above. It is characterized by being a light emitting diode element substrate.

  According to the present invention, it is possible to provide a glass ceramic composition capable of obtaining a sintered body in which phase separation of glass powder is suppressed, warpage is small, shape stability is good, and sufficient reflectance is obtained. it can. In addition, according to the present invention, it is possible to provide a light emitting diode element substrate having excellent shape stability and sufficient reflectivity. Furthermore, according to the present invention, it is possible to provide a light emitting device having excellent optical characteristics and productivity by using such a substrate for a light emitting diode element.

It is sectional drawing which shows an example of the light-emitting device which has a board | substrate for light emitting diode elements of this invention.

Hereinafter, the present invention will be described in detail.
The glass-ceramic composition of this invention contains 25 to 50 mass% glass powder, 30 to 60 mass% alumina powder, and 10 to 40 mass% zirconia powder.

Furthermore, glass powder, a SiO ₂ or 50 mol% 65 mol% or _less, B 2 _{O 3} of 10 mol% or more 18 mol% or less, CaO, SrO and one selected from BaO or two or more sum of 9 mol% or more 23 mol% Hereinafter, Al ₂ O ₃ is contained in an amount of 3 mol% or more and 13 mol% or less, and one or two selected from Na ₂ O and K ₂ O are contained in a total of 0.5 mol% or more and 6 mol% or less, and Al ₂ O ₃ , SrO and One or two or more selected from BaO are contained in a total amount of 8 mol% or more and 23 mol% or less.

  According to such a glass ceramic composition, by setting the content of each component constituting the glass powder within a predetermined range, phase separation of the glass powder can be suppressed, and variation in the degree of sintering of the glass powder during firing. Can be reduced. Therefore, a dense sintered body with little warpage and good shape stability can be obtained. Moreover, since a zirconia powder is mainly contained as a highly refractive filler for improving the reflectance, a sintered body having a high reflectance as a whole can be obtained.

Hereinafter, the glass ceramic composition will be specifically described.
Content of the glass powder in a glass-ceramics composition is 25-50 mass%.
If the content of the glass powder is less than 25% by mass, it may be difficult to obtain a dense sintered body (LTCC substrate) by firing. From the viewpoint of obtaining a denser sintered body, 30% by mass or more is preferable, and 33% by mass or more is more preferable. On the other hand, when the content of the glass powder exceeds 50% by mass, the bending strength of the sintered body may be insufficient. From the viewpoint of obtaining a sintered body with higher bending strength, it is preferably 45% by mass or less, and more preferably 40% by mass or less.

The glass powder preferably has a 50% particle size (D ₅₀ ) of 0.5 to ₅ μm.
If D ₅₀ is less than 0.5 [mu] m, it becomes industrially easily unlikely also to aggregate production, it is difficult to handle. Further, it is difficult to disperse in the glass ceramic composition. D ₅₀ is more preferably 0.8 μm or more, and still more preferably 1.5 μm or more. On the other hand, if D ₅₀ exceeds 5 [mu] m, it becomes difficult to obtain a dense sintered body by firing. In order to obtain a dense fired body by firing, D ₅₀ of the glass powder is more preferably 4 μm or less, and further preferably 3 μm or less. In addition, the 50% particle size (D ₅₀ ) in the present specification is a value measured by a laser diffraction scattering method.

The alumina powder is a component added to increase the bending strength of the sintered body, and is added in an amount of 30 to 60% by mass in the glass ceramic composition.
When the content of the alumina powder is less than 30% by mass, it is difficult to achieve a desired bending strength. From the viewpoint of obtaining a sintered body having higher bending strength, it is preferably 35% by mass or more, and more preferably 37% by mass or more. On the other hand, when the content of the alumina powder exceeds 60% by mass, not only the firing becomes insufficient and it becomes difficult to obtain a dense sintered body, but the smoothness of the surface of the sintered body may be impaired. From the viewpoint of obtaining a sintered body having a finer and smoother surface, it is preferably 55% by mass or less, and more preferably 52% by mass or less.

It is preferred _{D 50} of the alumina powder is 0.3 to 5 m. D ₅₀ is less than 0.5 [mu] m, it becomes difficult to achieve a sufficient flexural strength. Moreover, it becomes difficult to uniformly disperse the alumina powder in the glass ceramic composition. D ₅₀ is more preferably 0.6 μm or more, and further preferably 1.5 μm or more. On the other hand, if D ₅₀ exceeds 5 [mu] m, the smoothness of the surface of the sintered body is impaired, or to obtain a dense sintered body becomes difficult by calcination. From the viewpoint of obtaining a denser and smoother sintered body, D ₅₀ is preferably 4 μm or less, and more preferably 3 μm or less.

  A zirconia powder is added in order to improve the reflectance of a sintered compact, and 10-40 mass% is added in a glass ceramic composition. When the content of the zirconia powder is less than 10% by mass, it becomes difficult to obtain a sintered body having a practically sufficient reflectance, specifically, a reflectance of 85% or more. The reflectance in the present invention is at a wavelength of 460 nm. From the viewpoint of obtaining a sintered body with higher reflectivity, the content of the zirconia powder is preferably 11% by mass or more. More preferably, it is 12 mass% or more.

  On the other hand, when the content of the zirconia powder exceeds 40% by mass, it becomes difficult to obtain a dense sintered body. From the viewpoint of obtaining a denser sintered body, the content of the zirconia powder is preferably 30% by mass or less. More preferably, it is 26 mass% or less.

The zirconia powder may be unstabilized zirconia, but is preferably partially stabilized zirconia or stabilized zirconia that is at least partially stabilized by the addition of Y ₂ O ₃ , CaO, or MgO. . By using partially stabilized zirconia or stabilized zirconia, for example, a phase transition at a high temperature is suppressed, and a sintered body having various characteristics can be obtained. The kind of the partially stabilized zirconia is not necessarily limited, but Y ₂ O ₃ -added zirconia that can be easily obtained industrially at low cost is preferable. In particular, the amount of Y ₂ O ₃ added is preferably 0.1 to 10 mol%.

_{D 50} of the zirconia powder is preferably 0.05 to 5 [mu] m. When D ₅₀ is less than 0.05 μm, the size of the zirconia powder becomes excessively small with respect to the wavelength of light (460 nm in the present invention), and it becomes difficult to obtain a high reflectance. From the viewpoint of obtaining a higher reflectance, D ₅₀ is preferably 0.1 μm or more, and more preferably 0.15 μm or more. On the other hand, when D ₅₀ exceeds 5 μm, the size of the zirconia powder becomes excessively large with respect to the wavelength of light, and thus it may be difficult to obtain a high reflectance. From the viewpoint of obtaining a higher reflectance, D ₅₀ is preferably 3 μm or less, and more preferably 1.5 μm or less.

In industrially available zirconia powder, relatively small secondary particles (typically 0.05 μm) are formed by aggregation of very small primary particles (typically 0.05 μm or less). There are some that form (about 5 μm). Since the secondary particle diameter is more important than the primary particle diameter in order to obtain a high reflectivity, when the zirconia powder is composed of secondary particles, that D ₅₀ of the secondary particles is 0.05~5μm Is preferred. From the viewpoint of obtaining a higher reflectance, the D ₅₀ of the secondary particles is preferably 0.1 μm or more, and more preferably 0.15 μm or more. On the other hand, from the viewpoint of obtaining a high reflectance, the D ₅₀ of the secondary particles is preferably 3 μm or less, and more preferably 1.5 μm or less.

It is preferable that the glass ceramic composition basically does not contain a high refractive filler other than zirconia powder, but may contain 3% by mass or less of high refractive fillers other than zirconia powder in total. Examples of highly refractive fillers other than zirconia powder include those having a refractive index exceeding 1.95. For example, titania, titanium compounds such as barium titanate, strontium titanate, and potassium titanate, and titanium or zirconium as a main component. And other composite materials.
In particular, titania and other titanium compounds may cause titanium ions to elute into the glass during firing and cause the LTCC substrate to be colored. When the LTCC substrate is colored, the reflectivity of the LTCC substrate may be reduced. For this reason, the content of titania and other titanium compounds is more preferably 1% by mass or less, and more preferably, the glass ceramic composition does not substantially contain them.

As for the high refractive filler other than the zirconia powder, the D ₅₀ is preferably 0.05 to 5 μm like the zirconia powder. D ₅₀ of the high refractive filler other than zirconia powder is preferably 0.1 μm or more, and more preferably 0.15 μm or more. Further, D ₅₀ of the high refractive filler other than zirconia powder is preferably 3 μm or less, and more preferably 1.5 μm or less.

  Next, each component of the glass powder blended in the glass ceramic composition of the present invention will be described.

SiO ₂ is a component that suppresses crystallization of glass to improve stability and improves acid resistance, and is an essential component. The content of SiO _{2 in} the glass powder is 50 mol% or more. When the content of SiO ₂ is less than 50 mol%, crystals are likely to precipitate during firing and the sintered body tends to warp, and the acid resistance may not be sufficient. From the viewpoint of obtaining a glass having more excellent stability and acid resistance, the content of SiO ₂ is preferably 53 mol% or more.
On the other hand, the content of SiO _{2 in} the glass powder is 65 mol% or less. When the content of SiO ₂ exceeds 65 mol%, it is difficult to produce a homogeneous glass at low cost because the solubility is lowered, and a dense sintered body can be obtained because the sinterability of the glass is also lowered. There is a risk of not. From the viewpoint of obtaining a glass with more excellent productivity and sinterability, the content of SiO ₂ is preferably 64 mol% or more.

B ₂ O ₃ is a component that improves the sinterability of glass and is an essential component. The content of B ₂ O ₃ in the glass powder is 10 mol% or more.
If B ₂ O ₃ is less than 10 mol%, the sinterability is lowered, and it becomes difficult to obtain a dense sintered body. From the viewpoint of obtaining a glass with more excellent sinterability, the content of B ₂ O ₃ is more preferably 11 mol% or more, and further preferably 12 mol% or more. On the other hand, the content of B ₂ O ₃ in the glass powder is 18 mol% or less. If it exceeds 18 mol%, the acid resistance may not be sufficient. From the viewpoint of more excellent acid resistance, the content of B ₂ O ₃ is preferably 17 mol% or less, and more preferably 16 mol% or less.

CaO, SrO, and BaO are components that lower the melting temperature and improve the sinterability. The total content of CaO, SrO, and BaO (hereinafter referred to as RO) is 9 mol% or more and 23 mol% or less.
The content of RO in the glass powder is 23 mol% or less. When the RO content exceeds 23 mol%, crystals represented by anorthite (SiO ₂ —Al ₂ O ₃ —CaO) and the like may easily precipitate during firing. In addition, acid resistance may not be sufficient. From the viewpoint of making crystals more difficult to precipitate and more excellent in acid resistance, the RO content is preferably 20 mol% or less, more preferably 17 mol% or less.
On the other hand, from the viewpoint of obtaining a denser sintered body, the content of RO is preferably 12 mol% or more, and more preferably 13 mol% or more.

  Moreover, SrO and BaO have a tendency to worsen acid resistance than CaO. For this reason, content of SrO and BaO is each 15 mol% or less in a glass powder, and each 12 mol% or less is preferable. More preferably, it is 10 mol% or less.

  Moreover, MgO and ZnO can be contained in glass powder with CaO, SrO, and BaO. MgO and ZnO are components that improve the sinterability like CaO and the like. However, MgO and ZnO tend to promote crystallization more than CaO or the like. The contents of MgO and ZnO are each 5 mol% or less in the glass powder, preferably 3 mol% or less. The total content of CaO, SrO, BaO, MgO, and ZnO is 12 mol% or more and 35 mol% or less in the borosilicate glass powder.

Al ₂ O ₃ is a component that suppresses the phase separation of glass and improves stability, and is an essential component.
The content of Al ₂ O ₃ in the glass powder is 3 mol% or more. If the content of Al ₂ O ₃ is less than 3 mol%, the glass tends to be phase-separated, so that there is a possibility that the sintered body cannot be stably mass-produced. From the viewpoint of making phase separation more difficult, the content of Al ₂ O ₃ is preferably 4 mol% or more, and more preferably 5 mol% or more. On the other hand, the content of Al ₂ O ₃ in the glass powder is 13 mol% or less. When the content of Al ₂ O ₃ exceeds 13 mol%, crystals represented by anorthite (SiO ₂ —Al ₂ O ₃ —CaO) precipitate during firing, and the sintered body tends to warp or be sintered. The bending strength of the body may be reduced. Further, the acid resistance may not be sufficient. The content of Al ₂ O ₃ is preferably 11 mol% or less, and more preferably 10 mol% or less, from the viewpoint of less crystal precipitation and excellent acid resistance.

Na ₂ O and K ₂ O are components that improve the sinterability of the glass, and contain one or more selected from Na ₂ O and K ₂ O.
The total content of Na ₂ O and K ₂ O in the glass powder is 0.5 mol% or more.
If the total amount of Na ₂ O and K ₂ O is less than 0.5 mol%, it becomes difficult to obtain a dense sintered body because the sinterability decreases. From the viewpoint of obtaining a glass with more excellent sinterability, the total content of Na ₂ O and K ₂ O is preferably 1 mol% or more, and more preferably 1.5 mol% or more. On the other hand, when the total content of Na ₂ O and K ₂ O exceeds 6 mol%, chemical durability may be reduced. The content of Na ₂ O and K ₂ O is preferably 5 mol% or less, and more preferably 4 mol% or less. Moreover, since _{K 2} O is more likely to promote phase separation than Na ₂ O, the ratio of the Na ₂ O content the _{K 2} O content for (mol%) (mol%) , i.e. _K 2 O / The value of Na ₂ O is preferably less than 0.3.

Al ₂ O ₃ , SrO, and BaO are components that can obtain a very high effect of suppressing the phase separation of glass, and contain at least one kind.
From the viewpoint of suppressing the phase separation of the glass to a practically sufficient level, the total content of Al ₂ O ₃ , SrO, and BaO (hereinafter referred to as Al ₂ O ₃ + SrO + BaO) is 8 mol% or more. In order to further suppress the phase separation of the glass, Al ₂ O ₃ + SrO + BaO is preferably 8.5 mol% or more, and more preferably 9 mol% or more.
On the other hand, Al ₂ O ₃ , SrO, and BaO are all components that promote crystal precipitation. From the viewpoint of suppressing the precipitation of crystals during firing, Al ₂ O ₃ + SrO + BaO is 20 mol% or less. Al ₂ O ₃ + SrO + BaO is preferably at most 18 mol%, more preferably at most 16 mol%.

The glass powder contained in the glass ceramic composition consists essentially of the above components, but may contain other components as long as the object of the present invention is not impaired. For example, ZrO ₂ , La ₂ O ₃ , Gd ₂ O ₃ or the like can be contained for the purpose of improving chemical durability. In that case, it is preferable that these components are 10 mol% or less. More preferably, it is 7 mol%, More preferably, it is 5 mol% or less. In consideration of environmental load, this glass does not contain PbO.

Next, two types of glass included in the “glass powder” used in the glass ceramic composition of the present invention will be described. “Glass powder” is a glass in which the content of Al ₂ O ₃ is increased to suppress phase separation in the range of the content of each component described above (hereinafter referred to as “glass A”), and the content of CaO. It includes two types of glass, the amount of which is reduced and the amount of SrO and BaO is increased to suppress phase separation (hereinafter referred to as “glass B”).

[Glass A]
“Glass A” has SiO ₂ of 50 mol% or more and 65 mol% or less, B ₂ O ₃ of 10 mol% or more and 18 mol% or less, RO of 9 mol% or more and 23 mol% or less, Al ₂ O ₃ of more than 8 mol% and 13 mol% or less, Na ₂ O and _{K 2} contain one or two elements selected from O or less 0.5 mol% or more 6 mol% in _{total, 8mol Al 2 O 3, SrO} , 1 kind or two or more selected from BaO in total % Or more and 23 mol% or less.

“Glass A” has a content of Al ₂ O ₃ that suppresses phase separation greater than 8 mol% and less than or equal to 13 mol%, so that variation in the degree of sintering due to phase separation of the glass powder during firing can be suppressed.
From the viewpoint of improving the sinterability and the balance of phase separation suppression, the more preferable ranges of “Glass A” are 53 to 60 mol% of SiO ₂ , 11 to 16 mol% of B ₂ O _3, and 14 to 22 mol% of RO. , Al ₂ O ₃ is 9 to 12 mol%, 1 type or 2 types selected from Na ₂ O and K ₂ O are contained in total 1 to 4 mol%, and Al ₂ O ₃ + SrO + BaO is 8 mol% or more and 15 mol% or less. Is.

Hereinafter, the content of Al ₂ O ₃ in “glass A” will be described.
_{Since SiO 2, B 2 O 3,} RO, Na 2 O and _K 2 O, as well as with respect to the _{Al 2 O 3 + SrO + BaO} , a content similar to the glass powder as described above, it will not be described.

Al ₂ O ₃ is a component that improves the stability by suppressing the phase separation of the glass. The content of Al ₂ O ₃ in “Glass A” needs to be greater than 8 mol%. If the Al ₂ O ₃ content is 8 mol% or less, the glass tends to phase-separate, and it may be difficult to stably mass-produce the sintered body. From the viewpoint of making phase separation more difficult, the content of Al ₂ O ₃ is preferably 8.5 mol% or more, and more preferably 9 mol% or more.
On the other hand, the content of Al ₂ O ₃ in “glass A” is 13 mol% or less. When the content of Al ₂ O ₃ exceeds 13 mol%, crystals represented by anorthite (SiO ₂ —Al ₂ O ₃ —CaO) precipitate during firing, and the sintered body tends to warp, There is a possibility that the bending strength of the bonded body may decrease. In addition, acid resistance may not be sufficient. The content of Al ₂ O ₃ is preferably 12 mol% or less, and more preferably 11 mol% or less, from the viewpoint of less crystal precipitation and excellent bending strength.

[Glass B]
“Glass B” is composed of 50 mol% or more and 65 mol% or less of SiO ₂ , B ₂ O ₃ of 10 mol% or more and 18 mol% or less, CaO of 0 mol% or more and less than 9 mol%, and one or two selected from SrO and BaO. 3 mol% or more and 23 mol% or less, Al ₂ O ₃ is contained in an amount of ₃ mol% or more and 8 mol% or less, and one or two selected from Na ₂ O and K ₂ O are contained in a total amount of 0.5 mol% or more and 6 mol% or less. One or two or more selected from ₂ O ₃ , SrO, and BaO are contained in a total amount of 8 mol% to 23 mol%.

“Glass B” contains SrO or BaO as an essential component for suppressing phase separation. By using one or two selected from SrO and BaO as essential components and containing them in a total amount of 3 mol% or more and 23 mol% or less, even when the content of Al ₂ O ₃ is small, The phase can be suppressed. In addition, since SrO or BaO can enhance the sinterability of the glass, the content of CaO can be reduced to 0 mol% or more and less than 9 mol%, and crystal precipitation can be suppressed. Further, since the content of Al ₂ O ₃ is less, decrease in bending strength is suppressed.
From the viewpoint of the balance between suppression of phase separation of glass powder and improvement of sinterability, more preferable ranges of “glass B” are 57 to 65 mol% of SiO ₂ , 11 to 16 mol% of B ₂ O ₃ , and CaO. 5~8mol%, 5~11mol% in total of one or two species selected from SrO and BaO, 4~7mol% of _Al 2 _{O 3,} the one or two elements selected from Na ₂ O and _{K 2} O The total content is 1 to 4 mol%, and Al ₂ O ₃ + SrO + BaO is 8 mol% or more and 23 mol%.

[Glass B]
Hereinafter, the composition of “glass B” will be described.
_Since respect to _{SiO 2, B 2 O 3,} Na 2 O and _K 2 O, and _{Al 2 O 3 + SrO + BaO} , a content similar to the glass powder as described above, will not be described.

CaO is a component that easily causes phase separation, and the content of CaO in “glass B” is less than 9 mol%. When the content of CaO is 9 mol% or more, the glass tends to phase-separate and the sintered body tends to warp. In addition, crystals represented by anorthite (SiO ₂ —Al ₂ O ₃ —CaO) may easily precipitate during firing. In addition, acid resistance may not be sufficient. The content of CaO is preferably 8.5 mol% or less, more preferably 8 mol% or less, from the viewpoint of less occurrence of phase separation and less crystal precipitation.
On the other hand, since CaO is also a component that improves the sinterability, from the viewpoint of obtaining a denser sintered body, the content of CaO in “glass B” is preferably 5 mol% or more, and more preferably 7 mol% or more. .

“Glass B” contains at least one selected from SrO and BaO together with CaO. SrO and BaO are components that suppress the phase separation of the glass, lower the melting temperature, and improve the sinterability.
“Glass B” contains 3 to 23 mol% in total of one or two kinds selected from SrO and BaO. “Glass B” contains SrO and BaO as described above, and the CaO content is reduced instead. For this reason, when the total content of SrO and BaO is less than 3 mol%, the sinterability may be reduced, and a dense sintered body may not be obtained. On the other hand, the total content of SrO and BaO in “glass B” is 23 mol% or less. If the total content of SrO and BaO exceeds 23 mol%, the acid resistance may not be sufficient. In addition, the substrate is likely to warp due to the precipitation of crystals.
In addition, since SrO and BaO have a tendency to worsen acid resistance more than CaO, content of SrO and BaO is 12 mol% or less in a glass powder, respectively, and 10 mol% or less is respectively preferable. More preferably, it is 9 mol% or less.

Al ₂ O ₃ is a component that improves the stability by suppressing the phase separation of the glass.
The content of Al ₂ O ₃ in “Glass B” is 3 mol% or more. If the content of Al ₂ O ₃ is less than 3 mol%, the glass tends to be phase-separated, so that there is a possibility that the sintered body cannot be stably mass-produced. From the viewpoint of making phase separation more difficult, the content of Al ₂ O ₃ is preferably 4 mol% or more, and more preferably 5 mol% or more. On the other hand, the content of Al ₂ O ₃ in “glass B” is 8 mol% or less. When the content of Al ₂ O ₃ exceeds 8 mol%, crystals represented by anorthite (SiO ₂ —Al ₂ O ₃ —CaO) precipitate during firing, and the sintered body tends to warp or the sintered body There is a risk that the bending strength of the steel will decrease. The content of Al ₂ O ₃ is preferably 7 mol% or less, more preferably 6.5 mol% or less, from the viewpoint of less crystal precipitation and excellent bending strength.

  The glass powder can usually be produced by producing a glass having the above composition by a melting method and then pulverizing the glass. The pulverization method is not particularly limited, and may be dry pulverization or wet pulverization. In the case of wet pulverization, it is preferable to use water as a solvent. For pulverization, a pulverizer such as a roll mill, a ball mill, or a jet mill can be appropriately used. After pulverization, the glass may be dried and classified as necessary.

  The glass ceramic composition can be prepared by blending such glass powder, alumina powder, and zirconia powder, and if necessary, other components at a predetermined mass ratio and mixing them. The glass ceramic composition is usually used as a green sheet. That is, a glass ceramic composition, a resin such as polyvinyl butyral or an acrylic resin, and a plasticizer such as dibutyl phthalate, dioctyl phthalate, or butyl benzyl phthalate as necessary are blended and mixed. Next, a solvent such as toluene, xylene, or butanol is added to the mixture to form a slurry, and the slurry is formed into a sheet on a film of polyethylene terephthalate or the like by a doctor blade method or the like. Furthermore, it is set as a green sheet by drying what was shape | molded in the sheet form, and removing a solvent.

  If necessary, the green sheet is formed with a wiring pattern, a via that is a through conductor, or the like by screen printing using Ag paste or the like. Moreover, you may form the overcoat glass for protecting the wiring conductor etc. which are formed by baking of a wiring pattern by screen printing etc.

The green sheet can be made into a substrate for an LED element by processing into a desired shape after firing. Here, the LED element substrate may be obtained by firing one green sheet, or may be obtained by stacking and firing a plurality of green sheets.
Firing is usually performed for about 1 hour in a temperature range (around 550 ° C.) where the glass does not flow, and after debinding (degreasing) to decompose and remove the binder such as resin, the baking is performed at 850 to 950 ° C. for 20 to 20 ° C. Hold for 60 minutes. A more preferable firing temperature is 860 to 940 ° C. Since the melting point of Ag is about 960 ° C., baking at 950 ° C. or lower suppresses the softening of Ag during baking and facilitates maintaining the shape of the wiring pattern, vias, and the like.

In addition, since the LED element substrate has a high reflectance with respect to light in the visible light region, light from the light emitting element such as the LED element can be efficiently extracted forward, and a highly efficient light emitting device can be obtained. Can be provided.
Further, the LED element substrate preferably has a reflectance of 85% or more, more preferably 86% or more, more preferably 87%, from the viewpoint of practically sufficient optical characteristics. More preferably, it is the above.
In addition, the LED element substrate preferably has a glass phase crystallization ratio of 60% or less, more preferably 35% or less, from the viewpoint of suppressing warping during firing (during manufacturing). More preferably, it is 15% or less. Here, the crystallization rate refers to the existence ratio (volume ratio) of the crystalline region in the glass phase. The crystallization rate is measured, for example, by measuring the X-ray diffraction of the produced LED element substrate and evaluating the ratio between the diffraction peak intensity due to alumina particles (or zirconia particles) and the diffraction peak intensity due to crystals precipitated from the glass phase. Can be obtained. Alternatively, the degree of crystallinity can also be obtained by observing a cross section of the produced LED element substrate with an electron microscope and evaluating the area ratio between the precipitated crystal and the amorphous region.

  Such a light emitting diode element substrate (hereinafter referred to as an LED element substrate) can be suitably used for manufacturing a light emitting device (hereinafter referred to as an LED package). The LED package includes at least the above-described LED element substrate and the LED element mounted on the LED element substrate. Such an LED package can be suitably used for a backlight of, for example, a mobile phone or a large liquid crystal TV.

  FIG. 1 is a cross-sectional view showing an example of an LED package having the above-described LED element substrate. The LED package 1 has, for example, a substantially flat LED element substrate 2, and the LED element 4 is mounted on a mounting portion 21 provided at a substantially central portion thereof with an adhesive 3. The LED element substrate 2 has a pair of connection terminals 22 around the mounting portion 21, and a pair of electrodes (not shown) of the LED elements 4 are electrically connected to the connection terminals 22 via bonding wires 5. ing.

  Inside the LED element substrate 2, an energization via 23 is provided in the thickness direction so as to be electrically connected to the pair of connection terminals 22, and is electrically connected to the energization via 23. A pair of external electrode terminals 24 is provided to do this. Further, a thermal via 25 is provided directly below the mounting portion 21. Furthermore, the LED package 1 is configured by providing the molding material 6 so as to cover the LED elements 4 and the connection terminals 22.

According to this LED element substrate 2, since it is made of the glass ceramic composition described above, there is little warpage and excellent shape stability, and desired dimensional accuracy can be obtained.
Further, the LED element substrate 2 can be suitably used for the LED package 1 because it has a practically sufficient reflectance. Furthermore, the LED element substrate 2 has sufficient density (gas barrier properties), and can effectively suppress sulfidation of the wiring conductor.

(Examples 1-4, Comparative Examples 1-4)
The raw materials were blended and mixed so as to have the mass ratio shown in the glass powder column of Table 1, and this mixture was put in a platinum crucible and melted at 1500 to 1600 ° C. for 60 minutes, and then the molten glass was cooled to obtain a glass block A. Obtained.

  A part of the glass block A was cut out to prepare a glass block B having a cubic shape of about 10 mm square. This glass block B was heat-treated at 750 ° C. for 30 minutes and visually observed to confirm the occurrence of phase separation. “X” indicates that white turbidity or the like is generated on the glass due to phase separation, and “◯” indicates that the transparent state was maintained after the heat treatment and no change was visually confirmed compared with that before the heat treatment.

The glass block A was pulverized with an alumina ball mill for 20 to 60 hours using water as a solvent to obtain glass powder. When D ₅₀ of the glass powder was measured using a laser diffraction particle size distribution analyzer (SALD2100) manufactured by Shimadzu Corporation, all were 2.0 μm.

Next, glass powder, alumina powder, and zirconia powder were blended and mixed so that the mass ratio shown in the column of the glass ceramic composition in Table 1 was obtained to obtain a mixture. Incidentally, the alumina powder was used Showa Denko Co. _{AL47-H (D 50 = 2.1μm} ). Further, the zirconia powder is partially a stabilized zirconia powder manufactured by Daiichi Kigenso Kagaku Kogyo Co., Ltd. _{HSY-3F-J (D 50} = 0.56μm: 2 -order particle size) was used.
In Table 1, "-" in the column of "Glass ceramic composition" indicates that the glass ceramic composition was not manufactured (Comparative Examples 1, 3, and 4).

  50 g of this mixture, 15 g of an organic solvent (toluene, xylene, 2-propanol, 2-butanol mixed at a mass ratio of 4: 2: 2: 1), and 2.5 g of a plasticizer (di-2-ethylhexyl phthalate) Then, 5 g of a resin (polyvinyl butyral PVK # 3000K manufactured by Denka) and a dispersant (DISPERBYK180 manufactured by BYK Chemie) were mixed to obtain a slurry. This slurry was applied onto a PET film by a doctor blade method and dried to obtain a green sheet having a thickness of 0.2 mm.

Next, the reflectance of the sintered body made of such a green sheet was evaluated by the following method. The results are also shown in Table 1.
In Table 1, "-" in the column of "Reflectance of glass ceramic composition sintered body" indicates that the reflectance was not measured (Comparative Examples 1, 3, and 4).

(Reflectance)
The reflectance was measured by the following method. That is, one square green sheet having a side of about 30 mm, two laminated sheets, and three laminated sheets are each fired by holding at 875 ° C. for 30 minutes, and the thicknesses are 140 μm, 280 μm, and 420 μm. Three types of sintered bodies were obtained. The reflectance of these sintered bodies was measured using a spectroscope USB2000 and a small integrating sphere ISP-RF manufactured by Ocean Optics, and linearly complemented with respect to the thickness, whereby the reflectance of the sintered body having a thickness of 300 μm (unit: %) Was calculated. The reflectance was at a wavelength of 460 nm, and barium sulfate was used as a reference.

  As is clear from Table 1, it can be seen that the glass blocks of Examples 1 to 4 made of glass powder having a specific composition are free from dust and the phase separation is suppressed. Moreover, about the sintered compact of Examples 1-4 which consists of the glass ceramic composition which contains the glass powder of specific composition, an alumina powder, and a zirconia powder within the predetermined range, a reflectance of 85% or more can be obtained. I understand.

On the other _hand, the value of Al ₂ O 3 + SrO + BaO is about glass block of Comparative Examples 1 to 4 consisting of 8 mol% less than the glass powder, turbidity has occurred, the occurrence of phase separation was observed. The glass compositions of Comparative Examples 1, 2, 3, and 4 are the glass compositions described in Examples 1, 2, 7, and 12 of Patent Document 1, respectively.

DESCRIPTION OF SYMBOLS 1 ... LED package, 2 ... LED element substrate, 3 ... Adhesive, 4 ... LED element, 5 ... Bonding wire, 6 ... Molding material, 21 ... Mounting part, 22 ... Connection terminal, 23 ... Current supply via, 24 ... External electrode terminal, 25 ... thermal via

Claims (6)

25% by mass to 50% by mass of glass powder, 30% by mass to 60% by mass of alumina powder, and 10% by mass to 40% by mass of zirconia powder,
Said glass powder is a SiO ₂ or 50 mol% 65 mol% or _less, B 2 _{O 3} of 10 mol% or more 18 mol% or less, CaO, 1 or two or more sum of the following 9 mol% or more 23 mol% selected from SrO and BaO Al ₂ O ₃ is contained in an amount of 3 mol% or more and 13 mol% or less, and one or two selected from Na ₂ O and K ₂ O are added in a total amount of 0.5 mol% or more and 6 mol% or less. Al ₂ O ₃ , SrO and BaO A glass ceramic composition comprising one or more selected from the group consisting of 8 mol% to 23 mol% in total. Said glass powder is a SiO ₂ or 50 mol% 65 mol% or _less, B 2 _{O 3} of 10 mol% or more 18 mol% or less, CaO, 1 or two or more sum of the following 9 mol% or more 23 mol% selected from SrO and BaO , Al ₂ O ₃ greater than 8 mol% and less than or equal to 13 mol%, containing one or two selected from Na ₂ O and K ₂ O in total from 0.5 mol% to 6 mol%, Al ₂ O ₃ , SrO and The glass ceramic composition according to claim 1, comprising one or more selected from BaO in a total amount of 8 mol% to 23 mol%. The glass powder is 50 mol% or more and 65 mol% or less of SiO ₂ , B ₂ O ₃ is 10 mol% or more and 18 mol% or less, CaO is 0 mol% or more and less than 9 mol%, and one or two kinds selected from SrO and BaO in total. 3 mol% or more 23 mol% or less, _Al 2 _{O 3} of 3 mol% or more 8 mol% or less, and contains one or 0.5 mol% or more 6 mol% of two or a total of less selected from Na ₂ O and _{K 2} O, Al ₂ 2. The glass ceramic composition according to claim 1, comprising one or more selected from O ₃ , SrO and BaO in a total of 8 mol% to 23 mol%.   The glass ceramic composition according to any one of claims 1 to 3, wherein the zirconia powder is made of stabilized zirconia or partially stabilized zirconia.   A substrate for mounting a light emitting diode device, wherein the glass ceramic composition according to any one of claims 1 to 4 is molded and fired. A light emitting device comprising: a light emitting diode element substrate; and a light emitting diode element mounted on the light emitting diode element substrate,
6. The light emitting device according to claim 5, wherein the light emitting diode element substrate is the light emitting diode element substrate.

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