KR20230039667A - Electronic device and manufacturing method of electronic device - Google Patents

Abstract

The electronic device 1 includes an electronic component 2, a substrate on which the electronic component 2 is mounted, and a protective cap 4 bonded to the substrate 3 so that the electronic component 2 is accommodated therein. The protective cap 4 has a frame portion 6 made of a first transparent inorganic material and a lid portion 7 made of a second transparent inorganic material covering an opening at one end of the frame portion 6. The frame part 6 and the base material 3 are directly welded by the welding part 9.

Description

Electronic device and manufacturing method of electronic device

The present invention relates to electronic devices and methods of manufacturing electronic devices.

BACKGROUND OF THE INVENTION It has come to be used in various fields such as lighting and communication for reasons such as electronic devices equipped with electronic components such as LEDs, long life and energy saving.

In this type of light emitting device, in order to protect the electronic components, there is a case where a protective cap is covered on a base material on which the electronic components are mounted so that the electronic components are accommodated therein.

For example, as disclosed in Patent Literature 1, the protective cap includes a frame portion (second member) surrounding the periphery of the light emitting element and a cover portion (cover member) covering an opening at one end of the frame portion.

International Publication No. 2015/190242

In many cases, the frame portion of the protective cap and the base material on which the electronic component is mounted are bonded using a brazing material (for example, gold-tin solder). The substrate is composed of metal or metal nitride ceramics, and is often a high expansion coefficient material. On the other hand, the frame portion is composed of a transparent inorganic material such as glass, and may be a low expansion coefficient material. In such a case, the difference in thermal expansion coefficient between the base material and the frame part becomes large, and it is difficult to select a brazing material matching the thermal expansion coefficients of both the base material and the frame part. That is, when the coefficient of thermal expansion of the brazing material is matched to the coefficient of thermal expansion of the substrate, the difference in thermal expansion coefficient between the frame portion and the brazing material increases, and when the coefficient of thermal expansion of the brazing material is matched to the frame portion, the difference in coefficient of thermal expansion between the base material and the brazing material increases. As a result, residual stress is generated at or near the junction between the base material and the frame portion, and damage (for example, cracks or the like) is likely to occur. In this way, if the junction or its vicinity is damaged, the airtightness of the space for accommodating the electronic component is lowered, and there is a possibility that the electronic component is deteriorated.

An object of the present invention is to provide an electronic device capable of maintaining high confidentiality.

The present invention invented to solve the above problems is an electronic device having an electronic component, a substrate on which the electronic component is mounted, and a protective cap bonded to the substrate so that the electronic component is accommodated therein, wherein the protective cap is a first transparent A frame portion made of an inorganic material and a lid portion made of a second transparent inorganic material covering an opening of one end of the frame portion are characterized in that the frame portion and the base material are directly welded. In this way, since no other member is interposed between the frame part and the base material, the frame part and the base material can be reliably joined even if the difference between the thermal expansion coefficient of the frame part and the base material is large to some extent.

In the above structure, it is preferable that the frame part and the lid part are directly welded. In this way, since no other member (high expansion brazing material, adhesive, etc.) intervenes between the frame and the lid, the frame and lid are reliable even if the difference between the thermal expansion coefficient of the frame and the lid is large to some extent. can be bonded together.

In the above structure, it is preferable that the 1st transparent inorganic material is quartz glass. This is particularly effective when the electronic component is an element that emits or receives ultraviolet rays because the ultraviolet transmittance of the cover part is increased. In addition, "quartz glass" refers to an amorphous substance containing 90% by mass or more of SiO ₂ including synthetic quartz, fused quartz, and the like.

In the above structure, it is preferable that the second transparent inorganic material is a glass material having a softening point of 1000°C or less. In this way, the frame portion is easily softened when the frame portion and the base material are directly welded by, for example, laser bonding. For this reason, the side of the frame part can be softened, and the joining time of the lid part and the frame part can be shortened. For the same reason, when the frame portion and the lid portion are directly welded by, for example, laser bonding, since the frame portion is easily softened, the bonding time between the frame portion and the lid portion can be shortened. Here, "softening point" refers to the value measured based on the ASTMC 338 method.

In the above configuration, the second transparent inorganic material may be quartz glass. In this way, the ultraviolet transmittance of the frame portion is increased. For this reason, it is particularly effective when the electronic component is an element that emits or receives ultraviolet rays.

In the above configuration, the electronic component may be an ultraviolet LED.

The present invention invented to solve the above problems is a method of manufacturing an electronic device having an electronic component, a substrate on which the electronic component is mounted, and a protective cap bonded to the substrate so that the electronic component is accommodated therein, wherein the protective cap is A frame portion made of a first transparent inorganic material and a lid portion made of a second transparent inorganic material covering an opening at one end of the frame portion, by irradiating a laser to the contact portion between the frame portion and the substrate in a state in which the frame portion and the substrate are brought into contact with each other , characterized in that it is provided with a bonding step of directly welding the frame portion and the base material. In this way, since no other member is interposed between the frame part and the base material, the frame part and the base material can be reliably joined even if the difference between the thermal expansion coefficient of the frame part and the base material is large to some extent. Further, since the contact portion between the frame portion and the base material is locally heated by the laser, materials with low heat resistance can be used for components of electronic devices such as electronic components.

In the above configuration, a bonding step of directly welding the frame portion and the lid portion is further provided by irradiating a laser beam to the contact portion of the frame portion and the lid portion in a state where the frame portion and the lid portion are brought into contact with each other. In this way, since no other member is interposed between the frame portion and the lid portion, the frame portion and the lid portion can be reliably joined even when the difference between the thermal expansion coefficient of the frame portion and the lid portion is large to some extent.

According to the present invention, it is possible to provide an electronic device capable of maintaining high confidentiality.

1 is a cross-sectional view showing an electronic device according to a first embodiment.
FIG. 2 is a AA cross-sectional view of FIG. 1 .
Fig. 3 is a graph showing transmittance curves of BU-41 and quartz glass at a wavelength of 200 to 600 nm.
4 is a cross-sectional view showing a manufacturing process of the electronic device according to the first embodiment.
5 is a cross-sectional view showing a manufacturing process of the electronic device according to the first embodiment.
6 is a cross-sectional view showing a manufacturing process of the electronic device according to the first embodiment.
7 is a cross-sectional view showing a manufacturing process of the electronic device according to the first embodiment.
8 is a cross-sectional view showing a manufacturing process of the electronic device according to the first embodiment.
9 is a cross-sectional view showing an electronic device according to a second embodiment.
10 is a cross-sectional view showing an electronic device according to a third embodiment.

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described, referring drawings. Note that, in each embodiment, the same reference numerals are assigned to corresponding components, so that overlapping descriptions are omitted in some cases. In the case where only a part of the configuration is described in each embodiment, the configuration of the embodiment other than that previously described can be applied to other parts of the configuration. In addition, not only the combination of the configurations specified in the description of each embodiment, but also the configurations of a plurality of embodiments can be partially combined even if not specified unless there is a problem with the combination.

(1st Embodiment)

1 and 2 illustrate an electronic device 1 according to a first embodiment of the present invention.

The electronic device 1 according to the present embodiment includes an electronic component 2, a substrate 3 on which the electronic component 2 is mounted, and protection disposed on the substrate 3 so as to accommodate the electronic component 2 therein. A joint portion 5 for joining the cap 4, the substrate 3, and the protective cap 4 is provided. In the following description, for convenience, the base material 3 side is described as the bottom and the protective cap 4 side as the top, but the vertical direction is not limited thereto.

The electronic component 2 is not particularly limited, but examples thereof include optical devices such as laser modules, LEDs, optical sensors, imaging elements, and optical switches. In this embodiment, the electronic component 2 is an ultraviolet LED, and the electronic device 1 is a light emitting device.

The substrate 3 is made of, for example, metal, metal oxide ceramics, LTCC or metal nitride ceramics. As a metal, copper, metal silicon, etc. are mentioned, for example. As metal oxide ceramics, aluminum oxide etc. are mentioned, for example. As LTCC, what sintered the composite powder containing crystalline glass and a refractory filler, etc. are mentioned, for example. As metal nitride ceramics, aluminum nitride etc. are mentioned, for example. In this embodiment, the substrate 3 is made of aluminum nitride. The thermal expansion coefficient of aluminum nitride in the temperature range of 30 to 380°C is, for example, 46×10 ^-7 /°C. In addition, in this embodiment, the base material 3 is a plate-shaped body in which both the upper surface 3a and the upper surface 3b are constituted by a flat surface. In addition, the substrate 3 may have a concave portion formed in a portion of the upper surface 3a on which the electronic component 2 is mounted.

The protective cap 4 has a frame portion 6, a cover portion 7 covering an opening at one end of the frame portion 6, and a joint portion 8 joining the frame portion 6 and the cover portion 7, there is. In addition, it is preferable to form various functional films on the surface of the protective cap 4, and it is preferable to form an antireflection film in order to reduce light reflection loss, for example.

The frame portion 6 is a cylindrical body having a through hole H extending in the thickness direction (vertical direction) at the center. The frame portion 6 surrounds the electronic component 2 accommodated in the space corresponding to the through hole H. In the illustrated example, the frame portion 6 is configured in a rectangular cylinder, but other shapes such as a cylinder may be used. In addition, the inner wall surface 6c of the frame part 6 is formed from the lower surface 6b side to the upper surface 6a side of the frame part 6 in order to improve the extraction efficiency of ultraviolet rays through the cover part 7. It is composed of a slope that transitions from the inside to the outside as it faces. The inner wall surface 6c may be a non-sloping surface (vertical surface). The through hole H can be formed by subjecting the raw material of the frame portion 6 to etching processing, laser processing, sandblasting processing, or the like.

The frame portion 6 is made of a first transparent inorganic material. As a 1st transparent inorganic material, glass materials other than quartz glass (silica glass) and quartz glass are mentioned, for example. Quartz glass has a high ultraviolet transmittance. Here, "transparency" in the first transparent inorganic material and the second transparent inorganic material (described later) means that light emitted from the electronic component 2 composed of a light emitting element is transmitted, for example. More specifically, it indicates that the transmittance of light in the target wavelength range is 10% or more. The transmittance can be measured using UH 4150 manufactured by Hitachi High-Tech Science.

In the case where the frame portion 6 is made of a glass material other than quartz glass, it is preferable that the glass material is also an ultraviolet-transmitting glass. Hereinafter, glass materials other than quartz glass may simply be referred to as glass materials.

In the glass material of the frame portion 6, the transmittance at an optical path length of 0.7 mm and a wavelength of 200 nm is preferably 10% or more, 20% or more, 30% or more, 40% or more, 50% or more, or 60% or more. , 70% or more, particularly preferably 80% or more. In addition, the glass material of the frame part 6 WHEREIN: The transmittance in an optical path length of 0.7 mm and a wavelength of 250 nm is preferably 50% or more, 60% or more, 70% or more, particularly preferably 80% or more. Further, in the glass material of the frame portion 6, when the transmittance at an optical path length of 0.7 mm and a wavelength of 250 nm is T ₂₅₀ and the transmittance at an optical path length of 0.7 mm and a wavelength of 300 nm is T ₃₀₀ , The value of T ₂₅₀ /T ₃₀₀ is preferably 0.3 or more, 0.4 or more, 0.5 or more, 0.6 or more, 0.7 or more, 0.8 or more, 0.85 or more, particularly preferably 0.9 or more. In this way, although the transmittance of ultraviolet rays is inferior to that of quartz glass, the light emitted from the electronic component 2 composed of the ultraviolet LED can be transmitted without problems, and the extraction efficiency of ultraviolet rays can be maintained at a high level. In addition, "optical path length 0.7 mm" shall be used for measurement after producing an equivalent measurement sample having an optical path length of 0.7 mm even when the thickness of the glass material is thin. In addition, "transmittance at an optical path length of 0.7 mm and a wavelength of 200 nm" may be used for measurement after preparing a measurement sample having a thickness of 0.7 mm, and after measuring the transmittance in the thickness direction of the glass material, it is converted into an optical path length of 0.7 mm. A single value may be employed.

In the glass material of the frame portion 6, the strain point is preferably 430°C or higher, 460°C or higher, 480°C or higher, 500°C or higher, 520°C or higher, 530°C or higher, 550°C or higher, 600°C or higher, particularly Preferably it is 630 degreeC or more. If the strain point is too low, there is a risk that deformation of the frame portion 6 may occur during laser bonding, which will be described later. However, this can be suppressed by setting the strain point within the above numerical range. Here, "strain point" is a value measured based on the ASTMC 336 method.

In the glass material of the frame part 6, the softening point is preferably 1000°C or less, 950°C or less, 900°C or less, 850°C or less, particularly preferably 800°C or less. In this way, when the frame portion 6 and the cover portion 7 or the frame portion 6 and the base material 3 are directly welded by laser bonding or the like, the frame portion 6 is easily softened. Joining time can be shortened.

In the glass material of the frame portion 6, the temperature at 10 ^2.5 dPa·s is preferably 1580°C or less, 1550°C or less, 1520°C or less, 1500°C or less, 1480°C or less, particularly 1470°C or less. When the temperature at 10 ^2.5 dPa·s is too high, the meltability is lowered and the cost of glass production tends to rise rapidly. Here, "temperature at 10 ^2.5 dPa·s" can be measured by a platinum ball pulling method. The temperature at 10 ^2.5 dPa·s corresponds to the melting temperature, and the lower the temperature, the better the melting property.

In the glass material of the frame part 6, the coefficient of thermal expansion in the temperature range of 30 to 380°C is preferably 30×10 ^-7 /°C or higher, 40×10 ^-7 /°C or higher, or 50×10 ^-7 /°C or higher, 60×10 ^-7 /°C or higher, particularly preferably 70×10 ^-7 /°C or higher. In addition, in the glass material of the frame part 6, the coefficient of thermal expansion in the temperature range of 30 to 380°C is preferably 105×10 ^-7 /°C or lower, 100×10 -7 /°C or lower, 95×10 ^-7 /°C ^{or lower. 7} /°C or less, particularly preferably 90×10 ^-7 /°C or less. If the coefficient of thermal expansion is too low, it becomes difficult to match the coefficient of thermal expansion of various members, particularly glass frit. As a result, since it becomes difficult to lower the melting point of the glass frit, the temperature of the manufacturing process of the electronic device 1 increases, and the performance of the electronic device 1 tends to deteriorate. On the other hand, when the coefficient of thermal expansion is too high, the frame portion 6 is easily damaged by thermal shock. The thermal expansion coefficient of quartz glass in the temperature range of 30 to 380°C is, for example, 4.0×10 ^-7 /°C. Here, "coefficient of thermal expansion in the temperature range of 30-380 degreeC" can be measured using a dilatometer, for example.

The liquidus temperature of the glass material of the frame portion 6 is preferably less than 1150 ° C, 1120 ° C or less, 1100 ° C or less, 1080 ° C or less, 1050 ° C or less, 1030 ° C or less, 980 ° C or less, 960 ° C or less, 950 ° C or less, Especially preferably, it is 940 degreeC or less. Further, the liquidus viscosity of the glass material of the frame portion 6 is preferably 10 ^4.0 dPa·s or more, 10 ^4.3 dPa·s or more, 10 ^4.5 dPa·s or more, 10 ^4.8 dPa·s or more, or 10 ^5.1 dPa·s or more. , 10 ^5.3 dPa·s or more, particularly preferably 10 ^5.5 dPa·s or more. In this way, devitrification resistance is improved. Here, the “liquidus temperature” is the temperature at which crystals are precipitated after passing through a standard sieve of 30 mesh (500 μm), putting the glass powder remaining on the 50 mesh (300 μm) into a platinum boat, and holding it in a hot-head gradient furnace for 24 hours. is a value measured by microscopic observation. The "liquidus viscosity" is a value obtained by measuring the viscosity of glass at liquidus temperature by a platinum sphere pulling method.

The Young's modulus of the glass material of the frame part 6 is preferably 55 GPa or more, 60 GPa or more, 65 GPa or more, particularly preferably 70 GPa or more. When the Young's modulus is too low, deformation, bending, and breakage of the frame portion 6 tend to occur. Here, "Young's modulus" is a value measured by the resonance method.

The glass material of the frame portion 6 is a glass composition, in terms of mass%, SiO ₂ 50 to 80%, Al ₂ O ₃ +B ₂ O ₃ 1 to 45%, Li ₂ O+Na ₂ O+K ₂ O 0 to 25 %, preferably MgO+CaO+SrO+BaO 0 to 25%. As described above, the reason for limiting the content of each component is shown below. In addition, in description of content of each component, % display shows mass % except the case where there is a description in particular. “Al ₂ O ₃ +B ₂ O _3” is Al ₂ O ₃ and It means the total amount of B ₂ O ₃ . “Li ₂ O+Na ₂ O+K ₂ O” means the total amount of Li ₂ O, Na ₂ O, and K ₂ O. “MgO+CaO+SrO+BaO” means the total amount of MgO, CaO, SrO and BaO.

SiO ₂ is a main component forming the skeleton of glass. The content of SiO ₂ is preferably 50 to 80%, 55 to 75%, 58 to 70%, and particularly preferably 60 to 68%. When there is too little content of _SiO2 , a Young's modulus and acid resistance will fall easily. On the other hand, when the content of SiO ₂ is too large, the high-temperature viscosity increases, the meltability tends to decrease, devitrification crystals such as cristobalite tend to precipitate, and the liquidus temperature tends to increase.

Al ₂ O ₃ and B ₂ O ₃ are components that improve devitrification resistance. The content of Al ₂ O ₃ +B ₂ O ₃ is preferably 1 to 40%, 5 to 35%, and 10 to 30%, particularly preferably 15 to 25%. When the content of Al ₂ O ₃ +B ₂ O ₃ is too small, the glass tends to devitrify. On the other hand, when the content of Al ₂ O ₃ +B ₂ O ₃ is too large, the component balance of the glass composition is impaired, conversely, the glass tends to devitrify.

While Al ₂ O ₃ is a component that increases the Young's modulus, it is a component that suppresses phase separation and devitrification. The content of Al ₂ O ₃ is preferably 1 to 20%, 3 to 18%, particularly 5 to 16%. When the content of Al ₂ O ₃ is too small, the Young's modulus tends to decrease, and the glass tends to be easily separated and devitrified. On the other hand, when the content of Al ₂ O ₃ is too large, the high-temperature viscosity increases and the meltability tends to decrease.

B ₂ O ₃ is a component that enhances meltability and devitrification resistance, and also improves brittleness and enhances strength. The content of B ₂ O ₃ is preferably 3 to 25%, 5 to 22%, 7 to 19%, particularly 9 to 16%. When the content of B ₂ O ₃ is too small, the meltability and devitrification resistance tend to decrease, and the resistance to hydrofluoric acid-based chemical solutions tends to decrease. On the other hand, when the content of B ₂ O ₃ is too large, the Young's modulus and acid resistance tend to decrease.

Li ₂ O, Na ₂ O, and K ₂ O are components that reduce high-temperature viscosity, remarkably increase meltability, and contribute to initial melting of glass raw materials. The content of Li ₂ O+Na ₂ O+K ₂ O is preferably 0 to 25%, 1 to 20%, 4 to 15%, particularly 7 to 13%. When the content of Li ₂ O+Na ₂ O+K ₂ O is too small, the meltability tends to decrease. On the other hand, when the content of Li ₂ O + Na ₂ O + K ₂ O is too large, there is a possibility that the thermal expansion coefficient becomes unreasonably high.

Li ₂ O is a component that lowers the high-temperature viscosity, remarkably increases the meltability, and contributes to the initial melting of the glass raw material. The content of Li ₂ O is preferably 0 to 5%, 0 to 3%, or 0 to 1%, particularly preferably 0 to 0.1%. When the content of Li ₂ O is too small, in addition to easily lowering the meltability, there is a possibility that the coefficient of thermal expansion is unreasonably low. On the other hand, when there is too much content of _Li2O , glass will become easy to phase-separate.

Na ₂ O is a component that lowers high-temperature viscosity, remarkably increases meltability, and contributes to the initial melting of glass raw materials. Moreover, it is a component for adjusting a thermal expansion coefficient. The content of Na ₂ O is preferably 0 to 25%, 1 to 20%, 3 to 18%, 5 to 15%, and particularly preferably 7 to 13%. When the content of Na ₂ O is too small, in addition to easily lowering the meltability, there is a possibility that the coefficient of thermal expansion becomes unreasonably low. On the other hand, when the content of Na ₂ O is too large, there is a possibility that the thermal expansion coefficient becomes unreasonably high.

K ₂ O is a component that lowers high-temperature viscosity, remarkably increases meltability, and contributes to the initial melting of glass raw materials. Moreover, it is a component for adjusting a thermal expansion coefficient. The content of K ₂ O is preferably 0 to 15%, 0.1 to 10%, and particularly preferably 1 to 5%. When the content of K ₂ O is too large, there is a possibility that the thermal expansion coefficient becomes unreasonably high.

MgO, CaO, SrO, and BaO are components that lower high-temperature viscosity and increase meltability. The content of MgO+CaO+SrO+BaO is preferably 0 to 25%, 0 to 15%, 0.1 to 12%, or 1 to 5%. When there is too much content of MgO+CaO+SrO+BaO, glass becomes easy to devitrify.

MgO is a component that lowers high-temperature viscosity and increases meltability, and is a component that remarkably increases Young's modulus among alkaline earth metal oxides. The content of MgO is preferably 0 to 10%, 0 to 8%, or 0 to 5%, particularly preferably 0 to 1%. When there is too much content of MgO, devitrification resistance will fall easily.

CaO is a component that lowers high-temperature viscosity and remarkably improves meltability. In addition, among the alkaline earth metal oxides, since the raw material to be introduced is relatively inexpensive, it is a component that lowers the raw material cost. The content of CaO is preferably 0 to 15%, 0.5 to 10%, and particularly preferably 1 to 5%. When there is too much content of CaO, glass will become easy to devitrify. Moreover, when content of CaO is too small, it will become difficult to enjoy the said effect.

SrO is a component that enhances devitrification resistance. The content of SrO is preferably 0 to 7%, 0 to 5%, 0 to 3%, and particularly preferably 0 to less than 1%. When there is too much content of SrO, glass will become easy to devitrify.

BaO is a component that enhances devitrification resistance. The content of BaO is preferably 0 to 7%, 0 to 5%, 0 to 3%, and less than 0 to 1%. When there is too much content of BaO, glass will become easy to devitrify.

In addition to the above components, other components may be introduced as optional components. In addition, the content of components other than the above components is preferably 10% or less, 5% or less, particularly 3% or less in terms of total amount from the viewpoint of accurately enjoying the effect of the present invention.

ZnO is a component that enhances the meltability, but when it is contained in a large amount in the glass composition, the glass tends to devitrify. Therefore, the content of ZnO is preferably 0 to 5%, 0 to 3%, 0 to 1%, or less than 0 to 1%, particularly preferably 0 to 0.1%.

ZrO ₂ is a component that enhances acid resistance, but when it is contained in a large amount in the glass composition, the glass tends to devitrify. Therefore, the content of ZrO ₂ is preferably 0 to 5%, 0 to 3%, 0 to 1%, or 0 to 0.5%, particularly preferably 0.001 to 0.2%.

Fe ₂ O ₃ and TiO ₂ are components that reduce transmittance in the deep ultraviolet region. The content of Fe ₂ O ₃ +TiO ₂ is preferably 100 ppm or less, 80 ppm or less, 60 ppm or less, 0.1 to 40 ppm or less, particularly preferably 1 to 20 ppm. When the content of Fe ₂ O ₃ +TiO ₂ is too large, the glass is colored and the transmittance in the deep ultraviolet region tends to decrease. In addition, when the content of Fe ₂ O ₃ +TiO ₂ is too small, a high-purity glass raw material must be used, resulting in a rapid increase in batch cost. In addition, “Fe ₂ O ₃ +TiO _{2 ”} means the total amount of Fe ₂ O ₃ and TiO ₂ .

Fe ₂ O ₃ is a component that reduces transmittance in the deep ultraviolet region. The content of Fe ₂ O ₃ is preferably 100 ppm or less, 80 ppm or less, 60 ppm or less, 40 ppm or less, 20 ppm or less, 10 ppm or less, particularly preferably 1 to 8 ppm. When the content of Fe ₂ O ₃ is too large, the glass is colored and the transmittance in the deep ultraviolet region tends to decrease. In addition, when the content of Fe ₂ O ₃ is too small, high-purity glass raw materials must be used, resulting in a rapid increase in batch cost.

Fe ions in iron oxide exist in the state of Fe ²⁺ or Fe ³⁺ . When the proportion of Fe ²⁺ is too small, the transmittance in deep ultraviolet rays tends to decrease. Therefore, the mass ratio of Fe ²⁺ /(Fe ²⁺ +Fe ³⁺ ) in iron oxide is preferably 0.1 or more, 0.2 or more, 0.3 or more, 0.4 or more, particularly preferably 0.5 or more.

TiO ₂ is a component that reduces transmittance in the deep ultraviolet region. The content of TiO ₂ is preferably 100 ppm or less, 80 ppm or less, 60 ppm or less, 40 ppm or less, 20 ppm or less, 10 ppm or less, particularly preferably 0.5 to 5 ppm. When the content of TiO ₂ is too large, the glass is colored and the transmittance in the deep ultraviolet region tends to decrease. In addition, when the content of TiO ₂ is too small, a high-purity glass raw material must be used, resulting in a rapid increase in batch cost.

Sb ₂ O ₃ is a component that acts as a refining agent. The content of Sb ₂ O ₃ is preferably 1000 ppm or less, 800 ppm or less, 600 ppm or less, 400 ppm or less, 200 ppm or less, 100 ppm or less, particularly preferably less than 50 ppm. When the content of Sb ₂ O ₃ is too large, the transmittance in the deep ultraviolet region tends to decrease.

SnO ₂ is a component that acts as a clarifier. The content of SnO ₂ is preferably 2000 ppm or less, 1700 ppm or less, 1400 ppm or less, 1100 ppm or less, 800 ppm or less, 500 ppm or less, 200 ppm or less, particularly preferably 100 ppm or less. When the content of SnO ₂ is too large, the transmittance in the deep ultraviolet region tends to decrease.

F ₂ , Cl ₂ and SO ₃ are components that act as refining agents. The content of F ₂ +Cl ₂ +SO ₃ is preferably 10 to 10000 ppm. A suitable lower range of F ₂ +Cl ₂ +SO ₃ is at least 10 ppm, at least 20 ppm, at least 50 ppm, at least 100 ppm, at least 300 ppm, in particular at least 500 ppm, and a suitable upper range is at most 3000 ppm, at most 2000 ppm, at most 1000 ppm, especially at most 800 ppm. . In addition, each suitable lower limit range of F _{2 ,} Cl _{2 ,} SO ₃ is 10 ppm or more, 20 ppm or more, 50 ppm or more, 100 ppm or more, 300 ppm or more, particularly 500 ppm or more, and suitable upper limit ranges are 3000 ppm or less, 2000 ppm or less, 1000 ppm or less; In particular, it is 800 ppm or less. When there is too little content of these components, it will become difficult to exhibit a clarification effect. On the other hand, when there is too much content of these components, there exists a possibility that a clarification gas may remain|survive as a bubble in glass. In addition, “F ₂ +Cl ₂ +SO _3” means F _2, Cl ₂ and It means the total amount of SO ₃ .

The glass material of the frame part 6 can be produced, for example, by combining various glass raw materials to obtain a glass batch, then melting the glass batch, clarifying and homogenizing the obtained molten glass, and forming it into a predetermined shape.

In the manufacturing process of the glass material of the frame part 6, it is preferable to use a reducing agent as a part of glass raw material. In this way, Fe ³⁺ contained in the glass is reduced, and the transmittance in deep ultraviolet rays is improved. As the reducing agent, materials such as sawdust, carbon powder, metallic aluminum, metallic silicon, and aluminum fluoride can be used, but among these, metallic silicon and aluminum fluoride are preferable.

In the manufacturing process of the glass material of the frame part 6, it is preferable to use metal silicon as a part of glass raw material, and the addition amount is 0.001-3 mass %, 0.005-2 mass %, with respect to the total mass of a glass batch, 0.01 to 1% by mass, particularly preferably 0.03 to 0.1% by mass. If the addition amount of metal silicon is too small, Fe ³⁺ contained in glass will not be reduced, and the transmittance|permeability in deep ultraviolet will fall easily. On the other hand, when the addition amount of metallic silicon is too large, the glass tends to be colored brown.

As part of the glass raw material, it is also preferable to use aluminum fluoride (AlF ₃ ), and the addition amount thereof is 0.01 to 5% by mass, 0.05 to 4% by mass, and 0.1 to 3% by mass in terms of F ₂ with respect to the total mass of the glass batch. Mass %, 0.2-2 mass %, 0.3-1 mass % are preferable. On the other hand, if there is too much addition amount of aluminum fluoride, there exists a possibility that _F2 gas may remain as a bubble in glass. When the added amount of aluminum fluoride is too small, Fe ³⁺ contained in the glass is not reduced, and the transmittance in deep ultraviolet rays tends to decrease.

In the manufacturing process of the glass material of the frame part 6, it is preferable to shape|mold in flat form by the down-draw method, especially the overflow down-draw method. The overflow down-draw method is a method of forming a glass sheet by causing molten glass to overflow from both sides of a heat-resistant gutter-like structure and stretching and forming downward while merging the overflowing molten glass to the lowermost end of the gutter-like structure. In the overflow down-draw method, the surface to be the surface of the glass plate does not contact the gutter-shaped refractory material, and is molded in a free surface state. For this reason, while it becomes easy to produce a thin glass plate, board|board thickness nonuniformity can be reduced even if it does not grind|polish the surface. As a result, the manufacturing cost of a glass plate can be reduced. In addition, the structure and material of the gutter-shaped structure are not particularly limited as long as desired dimensions and surface accuracy can be realized. In addition, when performing downward stretch molding, the method of applying force is not particularly limited either. For example, a method of stretching by rotating a heat-resistant roll having a sufficiently wide width while in contact with the glass may be employed, or a method of stretching a plurality of pairs of heat-resistant rolls by bringing them into contact only near the end surface of the glass may be employed. .

As a method for forming the glass material of the frame portion 6, in addition to the down-draw method, for example, a slot down method, a re-draw method, a float method, or the like may be employed.

As a glass material of the frame part 6, specifically, BU-41 by Nippon Denki Glass Co., Ltd. can be used, for example. The coefficient of thermal expansion of BU-41 in the temperature range of 30 to 380°C is, for example, 42×10 ^-7 /°C.

The thickness (vertical dimension) of the frame portion 6 is preferably larger than the electronic component 2, preferably 0.01 to 1 mm larger than the electronic component 2, more preferably 0.05 to 0.5 mm larger, and 0.1 mm larger than the electronic component 2. Larger -0.2 mm is most preferred.

The lid portion 7 is made of a second transparent inorganic material. As a 2nd transparent inorganic material, what was illustrated as a 1st transparent inorganic material is similarly applicable. The second transparent inorganic material may be of the same material as the first transparent inorganic material, or may be of a different material. However, from the viewpoint of extraction efficiency of ultraviolet rays, it is preferable that the lid portion 7 is made of quartz glass. In this embodiment, the cover part 7 is comprised from quartz glass. Moreover, in this embodiment, the cover part 7 is a plate-shaped body in which both the upper surface 7a and the lower surface 7b are comprised by plane.

The thickness of the cover portion 7 (vertical dimension) is preferably 0.1 to 1.0 mm, more preferably 0.2 to 0.8 mm, and most preferably 0.3 to 0.6 mm.

In this embodiment, the junction part 5 which joins the frame part 6 and the base material 3 is formed by the welding part 9 by which the frame part 6 and the base material 3 were directly welded. Similarly, the junction part 8 which joins the frame part 6 and the cover part 7 is also formed by the welding part 10 where the frame part 6 and the cover part 7 are directly welded. The welded portions 9 and 10 are formed by laser bonding.

In detail, the welded portion 9 is formed by melting at least one side of the frame portion 6 and the base material 3 in a laser irradiation area and then solidifying the melted portion. That is, the welded portion 9 is composed of, for example, a material on at least one side of the frame portion 6 and the substrate 3, and does not substantially contain materials other than the frame portion 6 and the substrate 3. It is preferable not to Similarly, the welded portion 10 is formed by melting at least one side of the frame portion 6 and the lid portion 7 in the laser irradiation area and then solidifying the melted portion. That is, the welded portion 9 is constituted by, for example, a material on at least one side of the frame portion 6 and the cover portion 7, and materials other than the frame portion 6 and the cover portion 7 are substantially It is preferable not to include

The welded portions 9 and 10 are formed in a plurality (two in the illustrated example) in a concentric annular shape along the through hole H, but may be one. The plurality of welded portions 9 and 10 are separated from each other in the radial direction, but may overlap each other in the radial direction. Each of the welded portions 9 and 10 is configured in a square annular shape when viewed from a plan view, but is not limited thereto, and may be configured in a circular annular shape or other annular shapes.

The welded portion 9 is formed continuously over the frame portion 6 and the substrate 3 in the thickness direction. Similarly, the welded portion 10 is formed continuously over the frame portion 6 and the cover portion 7 in the thickness direction. In this embodiment, there is no interface between the frame portion 6 and the substrate 3 in the inside of the welded portion 9, and the frame portion 6 and the cover portion inside the welded portion 10. (7) There is no interface between them. Of course, in the inside of the welded parts 9 and 10, the interface may remain.

The width S1 of the welded portions 9 and 10 is preferably 10 to 200 μm, more preferably 10 to 100 μm, and most preferably 10 to 50 μm. The thickness S2 of the welded portions 9 and 10 is preferably 10 to 200 μm, more preferably 10 to 150 μm, and most preferably 10 to 100 μm.

The maximum value of the residual stress in the planar direction of the welded portions 9 and 10 is preferably 10 MPa or less, more preferably 7 MPa or less, and most preferably 5 MPa or less. The maximum value of the residual stress in the plane direction was measured by birefringence (unit: nm) in the vicinity of the junction using a birefringence meter: ABR-10A manufactured by Uniopt in a glass plate having dimensions of 10 mm × 10 mm or more, and measuring the birefringence (unit: nm) in the plane direction. It is the maximum value when converted to the residual stress of In addition, by measuring optical birefringence, that is, measuring the optical path difference of orthogonal linearly polarized waves, it is possible to estimate the residual stress value in the glass plate, and the differential stress F (MPa) generated by the residual stress is F = D It is expressed as /CW. “D” is the optical path difference (nm), “W” is the distance through which the polarized wave passes (cm), and “C” is the photoelastic constant (proportional constant), usually 20 to 40 (nm/cm)/(MPa) ) is the value of In addition, tensile stress and compressive stress exist in the residual stress in the plane direction, but the absolute values of both are evaluated in the above.

Fig. 3 shows transmittance curves of BU-41 (manufactured by Nippon Denki Glass Co., Ltd.) and quartz glass at a wavelength of 200 to 600 nm. As shown in the figure, quartz glass has a transmittance of 90% or more in the deep ultraviolet region (for example, a wavelength range of 200 to 350 nm) without a decrease in transmittance due to an increase in thickness. On the other hand, BU-41 has a transmittance of 84% or more at a thickness of 0.2 mm and a transmittance of 70% or more at a thickness of 0.5 mm in the deep ultraviolet region. That is, BU-41 has a good transmittance in the deep ultraviolet region, although slightly inferior to that of quartz glass. Specifically, in the state of the electronic device (light emitting device) 1, the extraction efficiency of ultraviolet rays (electronic component (ultraviolet ray LED)) when both the lid portion 7 and the frame portion 6 are made of quartz glass with a thickness of 0.6 mm. The output magnification of (2) is 89% on average, and the ultraviolet extraction efficiency when the lid part 7 is made of quartz glass with a thickness of 0.6 mm and the frame part 6 is made of BU-41 with a thickness of 0.6 mm. was an average of 88%. Therefore, even if the cover portion 7 is made of quartz glass and the frame portion 6 is made of a glass material (for example, BU-41) having ultraviolet transmittance other than quartz glass, the light extraction efficiency in the ultraviolet region can be reduced. can be maintained at a high level. However, from the viewpoint of improving the extraction efficiency of ultraviolet rays, it is preferable that both the lid portion 7 and the frame portion 6 are made of quartz glass.

4 to 7 illustrate a manufacturing method of the electronic device 1 according to the first embodiment of the present invention.

The manufacturing method of the electronic device 1 according to the present embodiment includes a first bonding step of bonding the lid part 7 and the frame part 6 to obtain the protective cap 4, and the electronic component 2 is mounted thereon. A second bonding step for bonding the substrate 3 and the protective cap 4 is provided.

In the first bonding step, first, as shown in FIG. 4 , the lid portion 7 and the frame portion 6 are prepared. Then, the lower surface 7b of the cover part 7 and the upper surface 6a of the frame part 6 are brought into direct contact. In this state, as shown in FIG. 5 , the laser L is condensed and irradiated to the contact portion between the cover portion 7 and the frame portion 6 by the laser irradiation device 11 . The laser L is irradiated from at least one side of the cover part 7 and the frame part 6. In this embodiment, the laser L is irradiated from the lid portion 7 side. Thereby, while forming the welding part 10 by welding the contact part, the frame part 6 and the cover part 7 are joined by the welding part 10. In this way, since no other member is interposed between the frame portion 6 and the lid portion 7, even if the difference between the thermal expansion coefficient of the frame portion 6 and the thermal expansion coefficient of the lid portion 7 is large to some extent, the frame portion (6) and the cover part (7) can be joined reliably.

As shown in Fig. 6, the laser L is scanned so as to draw an annular trajectory T along the through hole H from the outside of the through hole H. In this case, the laser L is scanned so that the irradiation area R is overlapped on the annular trajectory T and goes around the annular trajectory T. Alternatively, the laser L is scanned so as to circumnavigate the annular trajectory T a plurality of times. Further, in the case where a plurality of welded portions 10 are formed in a concentric annular shape, a plurality of annular trajectories T for scanning the laser L are also set in a concentric annular shape.

Alternatively, the joining portion may be formed in a frame shape by intersecting four straight lines in a square shape so as to surround the through hole H. Accordingly, since a plurality of protective caps 4 can be manufactured at one time, manufacturing efficiency of the electronic device 1 can be increased.

In the second bonding process, first, as shown in FIG. 7 , the protective cap 4 obtained in the first bonding process and the base material 3 on which the electronic component 2 is mounted are prepared. Subsequently, the lower surface 6b of the frame portion 6 and the upper surface 3a of the substrate 3 are brought into direct contact. In this state, as shown in FIG. 8 , the laser L is condensed and irradiated to the contact portion between the frame portion 6 and the substrate 3 by the laser irradiation device 11 . The laser L is irradiated from the frame portion 6 side that transmits the laser L in the frame portion 6 and the base material 3 . Thereby, while forming the welding part 9 by welding the contact part, the frame part 6 and the base material 3 are bonded by the welding part 9. In this way, since no other member is interposed between the frame portion 6 and the base material 3, even if the difference between the coefficient of thermal expansion of the frame portion 6 and the coefficient of thermal expansion of the base material 3 is large to some extent, the frame portion 6 ) and the substrate 3 can be bonded reliably.

Each of the arithmetic mean roughnesses of the lower surface 7b of the cover part 7, the upper surface 6a of the frame part 6, the lower surface 6b of the frame part 6, and the upper surface 3a of the substrate 3 Ra is preferably 2.0 nm or less, more preferably 1.0 nm or less, still more preferably 0.5 nm or less, and most preferably 0.2 nm or less. Arithmetic average roughness Ra means the value measured by the method based on JIS B0601:2001. In this way, since the lid part 7 and the frame part 6, or the frame part 6 and the base material 3 are brought into close contact with each other by the intermolecular force (optical contact) between the bonding surfaces, the handling property before laser bonding is improved. this improves

As the laser L, an ultrashort pulse laser having a pulse width in the order of picoseconds or femtoseconds is preferably used.

The wavelength of the laser L is not particularly limited as long as it is a wavelength that transmits through the glass member, but is preferably 400 to 1600 nm, and more preferably 500 to 1300 nm, for example. The pulse width of the laser L is preferably 10 ps or less, more preferably 5 ps or less, and most preferably 200 fs to 3 ps. The converging diameter of the laser L is preferably 50 μm or less, more preferably 30 μm or less, and preferably 20 μm or less.

The repetition frequency of the laser L needs to be sufficient to generate continuous heat accumulation, and specifically, it is preferably 100 kHz or more, more preferably 200 kHz or more, and still more preferably 500 kHz or more.

In addition, it is preferable to use a method (burst mode) in which one pulse is divided into a plurality of parts and the pulse interval is further shortened to irradiate. Thereby, heat accumulation becomes easy to occur, and the junction part 8 can be formed stably.

(Second Embodiment)

9 illustrates an electronic device 1 according to a second embodiment of the present invention. In 2nd Embodiment, the structure of the junction part 8 which joins frame part 6 and cover part 7 is different from 1st Embodiment.

In this embodiment, the frame part 6 and the cover part 7 are comprised from quartz glass. The bonding portion 8 is constituted by an adhesive layer 21 . That is, the frame part 6 and the cover part 7 do not directly contact each other, and the adhesive layer 21 is interposed between them. The adhesive layer 21 is formed, for example, by baking an adhesive material.

The coefficient of thermal expansion of the adhesive layer 21 in the temperature range of 30 to 380 ° C is -25 × 10 ^-7 to 25 × 10 ^-7 / ° C, and -20 × 10 ^-7 to 20 × 10 ^-7 / ° C It is preferably -15×10 ^-7 to 15×10 ^-7 /°C, more preferably -10×10 -7 to 10×10 -7 /°C, and most preferably -10×10 ^-7 to 10×10 ^-7 /°C. The coefficient of thermal expansion of quartz glass in the temperature range of 30 to 380°C is, for example, 4.0×10 ^-7 /°C. Therefore, when the adhesive layer 21 having the above thermal expansion coefficient is used, the thermal expansion coefficient of the frame portion 6 and the cover portion 7 composed of a low expansion coefficient material such as quartz glass and the thermal expansion coefficient of the adhesive layer 21 are can be matched. As a result, even if the adhesive layer 21 is used, the residual stress generated in or in the vicinity of the adhesive layer 21 can be reduced, and damage (such as cracking) of the protective cap 4 can be suppressed.

Although the thickness of the adhesive layer 21 is not specifically limited, If the thickness of the adhesive layer 21 is too small, the mechanical strength of the adhesive layer 21 will fall easily. On the other hand, also when the thickness of the adhesive layer 21 is too large, residual stress in the adhesive layer 21 may increase and mechanical strength may decrease. In addition, the size of the protective cap 4 or the electronic device 1 tends to increase. For this reason, the thickness of the adhesive layer 21 is preferably 10 μm to 100 μm, more preferably 20 μm to 80 μm, and most preferably 30 μm to 60 μm.

The adhesive layer 21 preferably includes glass. In this way, the heat resistance and airtightness of the adhesive layer 21 can be improved. In particular, when the adhesive layer 21 is made of crystallized glass, low expansion is facilitated, and the thermal expansion coefficients of the frame portion 6 and the cover portion 7 made of quartz glass are easily matched. Specifically, it is preferable that the adhesive layer 21 contains a β-quartz solid solution which is a low-expansion crystal. The content of the β-quartz solid solution in the adhesive layer 21 is preferably 75 to 99% by mass, 80 to 97% by mass, particularly 85 to 95% by mass. When the content of the β-quartz solid solution is too small, low expansion of the adhesive layer 21 tends to be difficult. On the other hand, when the content of the β-quartz solid solution is too large, the fluidity at the time of joining tends to decrease. In addition, the adhesive layer 21 containing crystallized glass is obtained by heat-treating the adhesive material (sealing material) containing crystalline glass.

As a specific example of the adhesive layer 21, as a composition, in mol%, SiO ₂ 48 to 75%, Al ₂ O ₃ 5 to 25%, Li ₂ O 5 to 30%, B ₂ O ₃ 5 to 23%, ZnO 0 to and those containing glass containing 10%. In particular, as a composition, in mol%, SiO ₂ 48 to 75%, Al ₂ O ₃ 35 to 25%, Li ₂ O 5 to 30%, B ₂ O ₃ 10 to 23% (but not including 10%) , glass containing 0 to 2.5% (but not including 2.5%) of ZnO is preferred. The reason why it was set as such is explained below. In addition, in the description regarding the content of each component below, unless otherwise specified, "%" means "mol%".

SiO ₂ is a component that forms the glass skeleton and is also a component of the β-quartz solid solution. The content of SiO ₂ is preferably 48 to 75%, 53 to 70%, particularly 58 to 65%. When the content of SiO ₂ is too small, the amount of precipitation of β-quartz solid solution decreases, and low thermal expansion characteristics become difficult to obtain. On the other hand, when the content of SiO ₂ is too large, the softening fluidity due to heat treatment at the time of bonding (at the time of sealing) tends to decrease because the softening point increases.

Al ₂ O ₃ is a component of β-quartz solid solution. The content of Al ₂ O ₃ is preferably 5 to 25%, 7 to 15%, particularly 7 to 13%. If the content of Al ₂ O ₃ is too small, the amount of β-quartz solid solution precipitated decreases, making it difficult to obtain low thermal expansion characteristics. On the other hand, when the content of Al ₂ O ₃ is too large, the softening fluidity due to heat treatment at the time of joining tends to decrease because the softening point increases.

Li ₂ O is a component of the β-quartz solid solution and also a component that lowers the softening point. The content of Li ₂ O is preferably 5 to 30%, 10 to 25%, particularly 10 to 20%. When the content of Li ₂ O is too small, the amount of precipitation of β-quartz solid solution decreases, and low thermal expansion characteristics become difficult to obtain. In addition, since the softening point increases, the softening fluidity due to heat treatment at the time of joining tends to decrease. On the other hand, if the content of Li ₂ O is too large, the content of Li ₂ O in the residual glass after heat treatment increases and the thermal expansion coefficient of the residual glass increases, resulting in difficulty in obtaining low thermal expansion characteristics.

B ₂ O ₃ is a component that forms a glass skeleton and lowers the softening point. The content of B ₂ O ₃ is preferably 5 to 23%, 10 to 23% (but not including 10%), 12 to 16%, and particularly preferably 13 to 15%. When the content of B ₂ O ₃ is too small, the softening point rises and the difference between the softening point and the crystallization temperature becomes small. Therefore, there is a tendency for crystals to precipitate before the softening flow due to the heat treatment at the time of bonding, and the fluidity tends to decrease. On the other hand, if the content of B ₂ O ₃ is too large, the ratio of the residual glass phase after heat treatment increases (the amount of precipitation of β-quartz solid solution decreases), and the coefficient of thermal expansion of the residual glass phase increases, resulting in low thermal expansion characteristics. This becomes difficult to obtain.

In addition, by appropriately adjusting the ratio of each content of B ₂ O ₃ and Li ₂ O, low thermal expansion characteristics are easily obtained. Specifically, it is preferable to adjust the value of B ₂ O ₃ /Li ₂ O to 0.5 to 1, 0.7 to 1, and particularly 0.8 to 1. In addition, "B ₂ O ₃ /Li ₂ O" means the molar ratio of each content of B ₂ O ₃ and Li ₂ O.

ZnO is a component that improves weatherability. In addition, there is an effect of improving the softening fluidity by heat treatment at the time of bonding. The content of ZnO is 0 to 10%, 0 to 2.5% (but not including 2.5%), and particularly preferably 0 to 2%. If the content of ZnO is too large, the amount of β-quartz solid solution precipitated decreases, or heterogeneous crystals that do not contribute to low expansion such as Zn-Al-based crystals tend to precipitate. In addition, the thermal expansion coefficient of the residual glass after heat treatment tends to increase. As a result, the coefficient of thermal expansion tends to increase.

Moreover, you may contain MgO, CaO, SrO, or BaO as a component which improves weather resistance. These components also have the effect of improving the softening fluidity by heat treatment at the time of bonding. The content of MgO+CaO+SrO+BaO is preferably 0 to 10%, 0 to 5%, particularly 0.1 to 2%. If the content of MgO+CaO+SrO+BaO is too large, the precipitation amount of β-quartz solid solution tends to decrease or the thermal expansion coefficient of the residual glass phase after heat treatment tends to increase. As a result, the coefficient of thermal expansion tends to increase.

Similarly, La ₂ O ₃ , ZrO ₂ or Bi ₂ O ₃ may be contained as a component for improving weather resistance. Among these, ZrO ₂ and Bi ₂ O ₃ also have an effect of improving softening fluidity by heat treatment at the time of bonding. The content of La ₂ O ₃ +ZrO ₂ +Bi ₂ O ₃ is preferably 0 to 10%, 0 to 5%, particularly 0.1 to 2%. If the content of La ₂ O ₃ +ZrO ₂ +Bi ₂ O ₃ is too large, the precipitation amount of β-quartz solid solution tends to decrease or the thermal expansion coefficient of the residual glass phase after heat treatment tends to increase. In particular, when the content of La ₂ O ₃ is too large, heterogeneous crystals that do not contribute to low expansion, such as La-B-based crystals, tend to precipitate. As a result, the coefficient of thermal expansion tends to increase. In addition, “La ₂ O ₃ +ZrO ₂ +Bi ₂ O _{3 ”} means the total amount of La ₂ O ₃ , ZrO ₂ and Bi ₂ O ₃ .

In addition to the above components, the total amount of Na ₂ O, K ₂ O, MnO, P ₂ O ₅ , MoO ₂ , TiO ₂ , V ₂ O ₅ and the like is 30% or less, 20%, etc., within a range that does not impair the effects of the present invention. It is possible to make it contain in the range of 10% or less below.

In addition, the adhesive layer 21 may contain a refractory filler powder for adjusting the thermal expansion coefficient. The content of the fire-resistant filler is preferably 0 to 30% by mass, 0.1 to 20% by mass, particularly 1 to 10% by mass. When the content of the refractory filler powder is too large, the bondability to the member to be joined tends to decrease.

As the refractory filler powder, cordierite, willemite, alumina, zirconium phosphate, zircon, zirconia, tin oxide, mullite, silica, β-eucryptite, β-spodumene, β-quartz solid solution, zirconium tungstate phosphate, etc. can be used. can

The adhesive material constituting the adhesive layer 21 is disposed between the frame portion 6 and the lid portion 7 in the form of powder, green compact, paste, or the like. When the adhesive material is used as a paste, a paste containing, for example, crystalline glass powder, resin, and solvent is applied. For application of the paste, a dispenser can be used, for example.

As the resin of the paste, acrylic acid ester (acrylic resin), ethyl cellulose, polyethylene glycol derivatives, nitrocellulose, polymethylene styrene, polyethylene carbonate, methacrylic acid ester and the like can be used. In particular, acrylic acid esters and ethyl cellulose are preferable because they have good thermal decomposition properties.

As the solvent for the paste, α-terpineol, pine oil, N,N'-dimethylformamide (DMF), higher alcohol, γ-butyrolactone (γ-BL), tetralin, butylcarbitol acetate, ethyl acetate , isoamyl acetate, diethylene glycol monoethyl ether, diethylene glycol monoethyl ether acetate, benzyl alcohol, toluene, 3-methoxy-3-methylbutanol, triethylene glycol monomethyl ether, triethylene glycol dimethyl ether, dipropylene Glycol monomethyl ether, dipropylene glycol monobutyl ether, tripropylene glycol monomethyl ether, tripropylene glycol monobutyl ether, propylene carbonate, N-methyl-2-pyrrolidone and the like can be used. In particular, α-terpineol is preferable because it has high viscosity and good solubility in resins and the like.

The firing temperature is preferably within the range of the softening point of the adhesive material ± 100 ° C, particularly the softening point ± 50 ° C. Specifically, the firing temperature is preferably in the range of, for example, 500°C to 800°C, particularly 600°C to 750°C. If the firing temperature is too low, the softening flow tends to become insufficient and the adhesive strength tends to deteriorate. On the other hand, when the firing temperature is too high, the fluidity tends to be excessive and bonding becomes difficult. In addition, when the adhesive material contains crystalline glass, crystal transition (for example, a crystal transition from a β-quartz solid solution to a β-spodumene solid solution) occurs, and the adhesive layer 21 may have high expansion. In addition, the firing of the adhesive material may be heating using a heating furnace or heating using a laser.

The average particle diameter D ₅₀ of the adhesive material is preferably 15 μm or less, 0.5 to 10 μm, particularly preferably 0.7 to 5 μm. If the particle size of the average particle diameter D ₅₀ is too large, there is a possibility that the number of pores in the adhesive layer 21 obtained after firing is too large, and the bonding strength is reduced. Here, "average particle diameter D _50" refers to a value measured with a laser diffraction device, and in a volume-based cumulative particle size distribution curve measured by a laser diffraction method, the accumulated amount is accumulated from the smaller particle side. 50% of the particle diameter.

(Third Embodiment)

10 illustrates an electronic device 1 according to a third embodiment of the present invention. In the third embodiment, the protective cap 4 is constituted by a single member without a junction between the frame portion 6 and the cover portion 7, which is different from the first and second embodiments. The frame portion 6 of the protective cap 4 composed of a single member is directly welded to the base material 3 by the welding portion 9.

In addition, this invention is not limited to the structure of the said embodiment, nor is it limited to the said effect. Various changes are possible in the present invention within a range not departing from the gist of the present invention.

In the above embodiment, after bonding the frame part 6 and the base material 3, you may bond the cover part 7 to the frame part 6. In this case, after bonding the frame part 6 and the base material 3, the electronic component 2 may be mounted on the base material 3, and then the cover part 7 may be joined to the frame part 6. However, when workability is considered, it is preferable to mount the electronic component 2 on the base material 3 before bonding the frame part 6 and the base material 3 together.

In the above embodiment, a reflective film may be formed on the inner circumferential surface of the frame portion 6 in order to improve the extraction efficiency of ultraviolet rays.

1: electronic device 2: electronic component
3: substrate 4: protective cap
5: junction 6: frame
7: cover part 8: joint part
9: welding part 10: welding part

Claims (8)

An electronic device having an electronic component, a substrate on which the electronic component is mounted, and a protective cap bonded to the substrate so that the electronic component is accommodated therein,
The protective cap includes a frame portion made of a first transparent inorganic material and a lid portion made of a second transparent inorganic material covering an opening at one end of the frame portion,
An electronic device characterized in that the frame portion and the substrate are directly welded. According to claim 1,
An electronic device in which the frame part and the cover part are directly welded. According to claim 1 or 2,
An electronic device wherein the first transparent inorganic material is quartz glass. According to any one of claims 1 to 3,
The electronic device wherein the second transparent inorganic material is a glass material having a softening point of 1000° C. or less. According to any one of claims 1 to 3,
An electronic device wherein the second transparent inorganic material is quartz glass. According to any one of claims 1 to 5,
An electronic device wherein the electronic component is an ultraviolet LED. A method of manufacturing an electronic device comprising an electronic component, a substrate on which the electronic component is mounted, and a protective cap bonded to the substrate so that the electronic component is accommodated therein,
The protective cap includes a frame portion made of a first transparent inorganic material and a lid portion made of a second transparent inorganic material covering an opening at one end of the frame portion,
and a bonding step of directly welding the frame portion and the substrate by irradiating a laser beam on a contact portion between the frame portion and the substrate in a state in which the frame portion and the substrate are brought into contact with each other. method. According to claim 7,
A method of manufacturing an electronic device, further comprising a bonding step of directly welding the frame portion and the cover portion by irradiating a laser to a contact portion between the frame portion and the cover portion in a state in which the frame portion and the cover portion are brought into contact with each other.

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