WO2023053688A1

WO2023053688A1 - Electronic device and method for manufacturing electronic device

Info

Publication number: WO2023053688A1
Application number: PCT/JP2022/028255
Authority: WO
Inventors: 隆史西宮; 徹平尾; 徹白神
Original assignee: 日本電気硝子株式会社
Priority date: 2021-09-29
Filing date: 2022-07-20
Publication date: 2023-04-06
Also published as: JP2023049453A

Abstract

This method is for manufacturing an electronic device 1 provided with an electronic component 2, a base material 3 on which the electronic component 2 is mounted, a frame material 6 made of glass and surrounding the electronic component 2 in a state where a one-end opening is joined to the base material 3, and a lid material 7 directly joined to the frame material 6 so as to close the other-end opening of the frame material 6. The method comprises: a joining preparation step for interposing a sealing material layer 5 containing a glass material between the base material 3 and the one-end opening of the frame material 6; and a real joining step for joining, after the joining preparation step, the base material 3 and the one-end opening of the frame material 6 by irradiating the sealing material layer 5, with a laser beam L, so as to soften and deform the sealing material layer.

Description

ELECTRONIC DEVICE AND METHOD FOR MANUFACTURING ELECTRONIC DEVICE

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

As a type of electronic device equipped with electronic components such as LEDs, there is a device that sterilizes using the light emitted by ultraviolet LEDs. In this kind of electronic device, a UV LED is arranged in a hermetic structure. Patent Document 1 discloses an example of an electronic device having an airtight structure.

The electronic device (light emitting device 1) disclosed in the same document includes an LED (light source 20), a base material (first member 11) on which the LED is mounted, and the LED with one end opening joined to the base material. and a lid member (cover member 40) joined to the frame member so as to close the other end opening of the frame member.

WO2015/190242

In the above electronic devices, the base material is often composed of metal, metal oxide ceramics, LTCC, or metal nitride ceramics. On the other hand, the frame material may be made of glass that transmits ultraviolet rays. In this case, when the base material and the frame material made of glass are joined together in the manufacture of the electronic device, the two may be directly fused together by laser irradiation. However, there has been a problem that the airtightness is likely to be impaired due to the high degree of difficulty in joining, such as the time it takes to determine the conditions for welding and processing.

In view of the above circumstances, the technical issue to be resolved is to improve the reliability of the airtight structure in electronic devices.

A method of manufacturing an electronic device for solving the above problems includes: an electronic component; a base material on which the electronic component is mounted; and a lid member directly joined to the frame member so as to close the other end opening of the frame member, the method for manufacturing an electronic device between the base material and the one end opening of the frame member. a joining preparation step in which a sealing material containing a glass material is interposed; and after the joining preparation step, a laser is irradiated to soften and deform the sealing material, thereby joining the base material and the opening at one end of the frame material. This step is characterized by comprising:

In this method, the base material and the frame material are joined by the joining preparation process and the main joining process. That is, when joining both the base material and the frame material made of glass, the laser is irradiated to the sealing material containing the glass material interposed between them instead of directly welding them. Then, the sealing material is softened and deformed to be joined. This makes it possible to avoid problems such as the time required for setting conditions and processing as in the case of directly welding the two, and as the degree of difficulty in joining becomes easier, the reliability of the airtight structure of the manufactured electronic device is improved. can be improved.

In the above method, the softening point of the sealing material is preferably 550°C or less.

If the softening point of the sealing material is excessively high, it will be necessary to irradiate the laser in the main joining process to heat the sealing material to that high softening point. This heating of the sealing material may damage the base material and the frame material. However, if the softening point of the sealing material is 550° C. or less, the above fears can be accurately eliminated.

In the above method, the sealing material preferably has a thermal expansion coefficient of 35×10 ^-7 /°C to 90×10 ^-7 /°C in the temperature range of 30°C to 200°C.

This makes it easier to match the thermal expansion coefficient of the sealing material with the thermal expansion coefficient of the base material and the frame material, which is advantageous in reducing the stress remaining in the sealing material after the main joining step. .

In the above method, the glass material contains 28 to 60% Bi ₂ O ₃ , 15 to 37% B ₂ O ₃ , 0 to 30% ZnO, and 1 to 40% CuO+MnO in terms of mol % of the glass composition. is preferred.

By doing so, it is possible to increase the sealing strength (bonding strength between the base material and the frame material) by the sealing material.

In the above method, the sealing material is at least one refractory material selected from cordierite, zircon, tin oxide, niobium oxide, zirconium phosphate ceramic, willemite, β-eucryptite, and β-quartz solid solution. Preferably, it further contains a filler powder.

By doing so, it becomes easier to match the coefficient of thermal expansion of the sealing material with that of the base material and the frame material. This is advantageous in preventing such situations from occurring.

In the above method, it is preferable to heat the base material before the main joining step.

By doing so, heat conduction to the base material side can be inhibited during laser irradiation in the main joining process, so that the sealing material can be softened and deformed efficiently in the main joining process.

In the above method, it is preferable to irradiate the laser in a state in which the sealing material is pressed by the base material and the opening at one end of the frame material in the main joining step.

By doing so, it is possible to promote softening deformation of the sealing material during laser irradiation in the main joining process.

In the above method, the joining preparation step and the main joining step may be performed after joining the frame material and the lid material. On the other hand, the frame member and the lid member may be joined after performing this joining step.

In the above-described method, when joining the frame material and the lid material, the lid material and the other end opening of the frame material are in contact with each other, and the contact portion between the two is irradiated with a laser. It is preferable to directly weld the cover material.

By doing so, for example, when a light-emitting device is manufactured as an electronic device, a situation in which a light-absorbing layer is formed at the joint portion due to the joint between the frame member and the lid member can be avoided. , it is possible to prevent the light extraction efficiency from deteriorating in the light emitting device.

An electronic device for solving the above problems includes an electronic component, a base material on which the electronic component is mounted, a frame member made of glass surrounding the electronic component with one end opening joined to the base material, and a frame member and a lid member directly joined to the frame member so as to close the other end opening of the electronic device, wherein the base member and the frame member are joined via a sealing material containing a glass material. It is characterized by

According to this device, it is possible to similarly obtain the actions and effects described above with respect to the method of manufacturing the electronic device described above.

According to the electronic device and the electronic device manufacturing method according to the present disclosure, it is possible to improve the reliability of the airtight structure in the electronic device.

1 is a cross-sectional view showing an electronic device; FIG. FIG. 2 is a cross-sectional view taken along the line AA of FIG. 1; It is sectional drawing which shows the manufacturing method of an electronic device. It is sectional drawing which shows the manufacturing method of an electronic device. It is a top view which shows the manufacturing method of an electronic device. FIG. 4 is a cross-sectional view showing a bonding preparation step in the method of manufacturing an electronic device; FIG. 4 is a cross-sectional view showing a bonding preparation step in the method of manufacturing an electronic device; FIG. 4 is a cross-sectional view showing a main joining step in the method of manufacturing an electronic device;

An electronic device and a method for manufacturing an electronic device according to embodiments will be described below with reference to the accompanying drawings.

1 and 2 illustrate an electronic device 1. FIG.

The electronic device 1 includes an electronic component 2, a base material 3 on which the electronic component 2 is mounted, a protective cap 4 disposed on the base material 3 so as to accommodate the electronic component 2 inside, and the base material 3. a layer of sealing material 5 joining with the protective cap 4; In the following description, for the sake of convenience, the side of the substrate 3 is taken as the bottom and the side of the protective cap 4 is taken as the top, but the vertical direction is not limited to this.

The electronic component 2 is not particularly limited, but examples 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 (light emitting element), 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. Examples of metals include copper and metallic silicon. Examples of metal oxide ceramics include aluminum oxide. Examples of LTCC include sintered composite powder containing crystallizable glass and refractory filler. Examples of metal nitride ceramics include aluminum nitride. In this embodiment, the base material 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. Moreover, in this embodiment, the base material 3 is a plate-like body in which both the upper surface 3a and the lower surface 3b are flat surfaces. In addition, the substrate 3 may be provided with a concave portion in a portion of the upper surface 3a where the electronic component 2 is mounted.

The protective cap 4 includes a frame member 6 that surrounds the electronic component 2 while being joined to the base material 3, a cover member 7 that covers and closes the frame member 6 from above, and joins the frame member 6 and the cover member 7. a joint portion 8; The joint portion 8 is formed of a weld portion 9 in which the frame member 6 and the lid member 7 are directly welded (directly joined). Various functional films are preferably formed on the surface of the protective cap 4. For example, an antireflection film may be formed on at least one of the upper and

lower surfaces

7a and 7b of the lid member 7 in order to reduce light reflection loss. is preferred. Antireflection films are preferably formed on the upper and

lower surfaces

7a and 7b of the lid member 7, respectively. The antireflection film may be formed only on a portion of at least one of the upper and

lower surfaces

7a and 7b of the lid member 7 corresponding to the through holes H of the frame member 6, or may be formed on the entire surface. As the antireflection film, for example, a dielectric multilayer film in which a low refractive index layer having a relatively low refractive index and a high refractive index layer having a relatively high refractive index are alternately laminated is preferable. This makes it easier to control the reflectance at each wavelength. The antireflection film can be formed by, for example, a sputtering method, a CVD method, or the like. The reflectance of the antireflection film in the wavelength band (for example, 250 to 350 nm) of the light emitted from the electronic component 2 is, for example, 1% or less, 0.5% or less, 0.3% or less, particularly 0.1% or less. is preferably

The frame member 6 is a cylindrical body having a through hole H extending in the thickness direction (vertical direction) at the center. Thereby, openings are formed at the upper end and the lower end of the frame member 6, respectively. The frame member 6 surrounds the electronic component 2 accommodated in the space corresponding to the through hole H. As shown in FIG. The upper end opening of the frame member 6 is formed by an upper end surface 6a that is annular in plan view, and the lower end opening of the frame member 6 is similarly formed by a lower end surface 6b that is annular in plan view. In the illustrated example, the frame member 6 is configured as a rectangular cylinder, but may be of other shapes such as a cylinder. In addition, the inner wall surface 6c of the frame member 6 shifts from the inside to the outside as it goes from the lower end surface 6b side to the upper end surface 6a side of the frame member 6 in order to improve the efficiency of extracting ultraviolet rays through the lid member 7. Consists of sloping surfaces. The inner wall surface 6c may be a non-inclined surface (vertical surface). The through holes H can be formed by subjecting the base material of the frame member 6 to etching, laser processing, sandblasting, or the like.

A reflective film for reflecting the light emitted from the electronic component 2 may be formed on the inner wall surface 6c of the frame member 6. The reflective film is preferably made of resin paint or glass paste containing metals such as aluminum and gold, and ceramics such as alumina, zirconia and titania.

The thickness of the reflective film is preferably 0.1 to 100 μm, for example.

The reflectance of the reflective film in the wavelength band (for example, 250 to 350 nm) of light emitted from the electronic component 2 is preferably 10% or more, 20% or more, 30% or more, 40% or more, 50% or more, 60% or more. is preferable, and 70% or more is particularly preferable. Here, the reflectance can be calculated by measuring the transmittance at each wavelength in the wavelength range of 250 to 350 nm using UH-4150 manufactured by Hitachi High-Tech Science.

As a method for forming the reflective film on the inner wall surface 6c of the frame member 6, it is desirable to use a spray coating method. When using the spray coating method, a spray coating liquid (liquid that becomes a reflective film) is applied to the inner wall surface 6c of the frame member 6 while the flat portions of the upper and

lower end surfaces

6a and 6b (upper and lower end openings) of the frame member 6 are protected by masks. A reflective film can be easily formed on the inner wall surface 6c of the frame member 6 by coating and then peeling off the mask. Note that the method of forming the reflective film is not limited to this, and for example, a dip coating method or the like can also be used. When the dip coating method is used, the frame material 6 having the through holes H is immersed in a dip coating liquid (liquid that becomes a reflective film), and then formed on the unnecessary portions of the surface of the frame material 6 (upper and

lower end surfaces

6a, 6b, etc.). A reflective film can be formed on the inner wall surface 6c of the frame member 6 by removing the reflective film formed thereon by polishing or the like. In this case, by polishing the upper end surface 6a of the frame member 6 when removing the unnecessary portion of the reflective film, the surface precision when joined to the lid member 7 can be adjusted.

The frame material 6 is made of glass having a thermal expansion coefficient of 30×10 ^-7 to 100×10 ^-7 /°C in the temperature range of 30 to 380°C. The thermal expansion coefficient of the frame material 6 is preferably 40×10 ⁻⁷ /° C. or higher, more preferably 50×10 ⁻⁷ /° C. or higher, still more preferably 60×10 ⁻⁷ /° C. or higher, particularly preferably 70×10 −7 /° C. or higher. ^-7 /°C or higher. Also, the thermal expansion coefficient of the frame member 6 is preferably 95×10 ⁻⁷ /° C. or less, particularly preferably 90×10 ⁻⁷ /° C. or less. By doing so, the thermal expansion coefficient of the frame member 6 matches that of the base material 3 made of metal, metal nitride ceramics, or the like.

The glass forming the frame member 6 is preferably ultraviolet-transmitting glass. Specifically, in the glass constituting the frame member 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, and 60%. 70% or more, particularly preferably 80% or more. Further, in the glass forming the frame material 6, the transmittance at 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, and particularly preferably 80% or more. Furthermore, in the glass constituting the frame material 6, when the transmittance at an optical path length of 0.7 mm and a wavelength of 250 nm is T250, and the transmittance at an optical path length of 0.7 mm and a wavelength of 300 nm is T300, the value of T250/T300 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, and particularly preferably 0.9 or more. In this way, compared with the case where the frame member 6 is made of, for example, quartz glass, the transmittance of ultraviolet rays is at the same level, and the light emitted from the electronic component 2 made of an ultraviolet LED can be transmitted without problems. It is possible to maintain the efficiency of extracting ultraviolet rays at a high level.

The strain point of the glass forming the frame material 6 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, and particularly preferably 550°C or higher.

The softening point of the glass forming the frame member 6 is preferably 1000°C or lower, 950°C or lower, 900°C or lower, 850°C or lower, and particularly preferably 800°C or lower. In this way, when the frame member 6 and the lid member 7 are directly welded by laser welding or the like, the frame member 6 is easily softened, so that the bonding time can be shortened.

The temperature of the glass constituting the frame material 6 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, and particularly preferably 1470° C. or less. If the temperature at 10 ^2.5 dPa·s is too high, the meltability of the glass is lowered, which tends to increase the manufacturing cost of the glass. Here, the "temperature at 10 ^2.5 dPa·s" can be measured by the platinum ball pull-up method. The temperature at 10 ^2.5 dPa·s corresponds to the melting temperature, and the lower the temperature, the better the meltability.

The liquidus temperature of the glass forming the frame material 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, or 950°C or less. , and particularly preferably 940° C. or less. The liquidus viscosity of the glass forming the frame member 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. Above, it is 10 ^5.3 dPa·s or more, and particularly preferably 10 ^5.5 dPa·s or more. By doing so, the devitrification resistance is improved. Here, the "liquidus temperature" refers to the glass powder that passes through a 30-mesh (500 μm) standard sieve and remains on the 50-mesh (300 μm) sieve. It is a value obtained by measuring the precipitation temperature by microscopic observation. The "liquidus viscosity" is a value obtained by measuring the viscosity of the glass at the liquidus temperature by the platinum ball pull-up method.

The Young's modulus of the glass forming the frame material 6 is preferably 55 GPa or higher, 60 GPa or higher, 65 GPa or higher, and particularly preferably 70 GPa or higher. If the Young's modulus is too low, the frame member 6 is likely to be deformed, warped, and damaged. Here, "Young's modulus" refers to a value measured by a resonance method.

The glass constituting the frame member 6 has a glass composition of 50 to 80% SiO ₂ , 1 to 45% Al ₂ O ₃ +B ₂ O ₃ , 0 to 25% Li ₂ O + Na ₂ O + K ₂ O, and MgO + CaO + SrO + BaO in mass %. It preferably contains 0 to 25%. The reasons for limiting the content of each component as described above are as follows. In addition, in description of the content of each component about the glass which comprises the frame material 6, % display represents the mass % unless there is a notice in particular.

SiO ₂ is the main component that forms the skeleton of glass. The content of SiO ₂ is preferably 50-80%, 55-75%, 58-70%, particularly preferably 60-68%. If the SiO ₂ content is too low, the Young's modulus and acid resistance tend to decrease. On the other hand, if the SiO ₂ content is too high, the viscosity at high temperatures tends to increase and the meltability tends to decrease. Become.

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 1-40%, 5-35%, 10-30%, particularly preferably 15-25%. If the content of Al ₂ O ₃ +B ₂ O ₃ is too small, the glass tends to devitrify. On the other hand, if the content of Al ₂ O ₃ +B ₂ O ₃ is too large, the component balance of the glass composition is impaired, and the glass tends to devitrify.

Al ₂ O ₃ is a component that increases Young's modulus and suppresses phase separation and devitrification. The content of Al ₂ O ₃ is preferably 1-20%, 3-18%, particularly preferably 5-16%. If the content of Al ₂ O ₃ is too small, the Young's modulus tends to decrease, and the glass tends to undergo phase separation and devitrification. On the other hand, if the content of Al ₂ O ₃ is too high, the high-temperature viscosity increases and the meltability tends to decrease.

B ₂ O ₃ is a component that enhances meltability and resistance to devitrification, and is a component that improves scratch resistance and enhances strength. The content of B ₂ O ₃ is preferably 3-25%, 5-22%, 7-19%, particularly preferably 9-16%. If the B ₂ O ₃ content is too low, the meltability and resistance to devitrification tend to deteriorate, and the resistance to hydrofluoric acid-based chemicals tends to deteriorate. On the other hand, if the B ₂ O ₃ content is too high, Young's modulus and acid resistance tend to decrease.

Li ₂ O, Na ₂ O and K ₂ O are components that lower the high-temperature viscosity to remarkably improve the meltability and contribute to the initial melting of the glass raw material. The content of Li ₂ O+Na ₂ O+K ₂ O is preferably 0-25%, 1-20%, 4-15%, particularly preferably 7-13%. If the content of Li ₂ O+Na ₂ O+K ₂ O is too small, the meltability tends to be lowered. On the other hand, if the content of Na ₂ O is too high, the coefficient of thermal expansion may become unduly high.

Li ₂ O is a component that lowers the high-temperature viscosity and remarkably enhances the meltability and contributes to the initial melting of the glass raw material. The content of Li ₂ O is preferably 0-5%, 0-3%, 0-1%, particularly preferably 0-0.1%. If the content of Li ₂ O is too low, the meltability tends to decrease, and the coefficient of thermal expansion may unduly decrease. On the other hand, if the content of Li ₂ O is too high, the glass tends to undergo phase separation.

Na ₂ O is a component that lowers the high-temperature viscosity and remarkably enhances the meltability, and contributes to the initial melting of the glass raw material. It is also a component for adjusting the coefficient of thermal expansion. The content of Na ₂ O is preferably 0-25%, 1-20%, 3-18%, 5-15%, particularly preferably 7-13%. If the content of Na ₂ O is too low, the meltability tends to be lowered and the coefficient of thermal expansion may be lowered unduly. On the other hand, if the content of Na ₂ O is too high, the coefficient of thermal expansion may become unduly high.

K ₂ O is a component that lowers the high-temperature viscosity and remarkably enhances the meltability and contributes to the initial melting of the glass raw material. It is also a component for adjusting the coefficient of thermal expansion. The content of K ₂ O is preferably 0-15%, more preferably 0.1-10%, particularly preferably 1-5%. If the K ₂ O content is too high, the coefficient of thermal expansion may be unduly 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 0-25%, 0-15%, 0.1-12%, 1-5%. If the content of MgO+CaO+SrO+BaO is too high, the glass tends to devitrify.

MgO is a component that lowers high-temperature viscosity and increases meltability, and among alkaline earth metal oxides, it is a component that significantly increases Young's modulus. The content of MgO is preferably 0-10%, 0-8%, 0-5%, particularly preferably 0-1%. If the MgO content is too high, the devitrification resistance tends to decrease.

CaO is a component that lowers high-temperature viscosity and significantly increases meltability. In addition, among the alkaline earth metal oxides, since the raw material to be introduced is relatively inexpensive, it is a component that reduces the raw material cost. The CaO content is preferably 0-15%, more preferably 0.5-10%, and particularly preferably 1-5%. If the CaO content is too high, the glass tends to devitrify. If the content of CaO is too small, it becomes difficult to obtain the effect of improving meltability and the effect of reducing raw material cost.

SrO is a component that enhances devitrification resistance. The content of SrO is preferably 0-7%, 0-5%, 0-3%, particularly preferably 0-1%. If the SrO content is too high, the glass tends to devitrify.

BaO is a component that enhances devitrification resistance. The content of BaO is preferably 0-7%, 0-5%, 0-3%, 0-1%. If the BaO content is too high, the glass tends to devitrify.

In addition to the above components, other components listed below may be introduced as optional components. The total content of components other than the above components is preferably 10% or less, 5% or less, and particularly preferably 3% or less.

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

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

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, 0.1-40 ppm or less, particularly preferably 1-20 ppm. If the content of Fe ₂ O ₃ +TiO ₂ is too large, the glass will be colored, and the transmittance in the deep ultraviolet region will tend to decrease. If the content of Fe ₂ O ₃ +TiO ₂ is too low, high-purity glass raw materials must be used, resulting in an increase in batch cost.

Fe ₂ O ₃ is a component that lowers the 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. If the content of Fe ₂ O ₃ is too high, the glass tends to be colored and the transmittance in the deep ultraviolet region tends to decrease. If the content of Fe ₂ O ₃ is too low, a high-purity glass raw material must be used, resulting in an increase in batch cost.

Fe ions in iron oxide exist in the form of Fe ²⁺ or Fe ³⁺ . If the proportion of Fe ²⁺ is too low, 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, and particularly preferably 0.4 or more. 5 or more.

TiO ₂ is a component that lowers the 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. If the content of TiO ₂ is too high, the glass tends to be colored and the transmittance in the deep ultraviolet region tends to decrease. If the content of TiO ₂ is too low, high-purity glass raw materials must be used, resulting in an 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. If the Sb ₂ O ₃ content is too high, the transmittance in the deep ultraviolet region tends to decrease.

SnO ₂ is a component that acts as a fining agent. The SnO ₂ content 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. If the SnO ₂ content is too high, the transmittance in the deep ultraviolet region tends to decrease.

_F2 , _Cl2 and _SO3 are components that act as fining agents. The content of F ₂ +Cl ₂ +SO ₃ is preferably 10-10000 ppm. The preferred 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, especially 500 ppm or more, and the preferred upper limit range is 3000 ppm or less, 2000 ppm or less, 1000 ppm or less, especially 800 ppm or less. is. Further, each of F ₂ , Cl ₂ and SO ₃ preferably has a lower limit range of 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 a preferable upper limit range of 3000 ppm or less and 2000 ppm or less. It is 1000 ppm or less, especially 800 ppm or less. If the content of these components is too low, it will be difficult to exhibit the refining effect. On the other hand, if the content of these components is too high, the fining gas may remain in the glass as bubbles.

The glass that constitutes the frame member 6 is prepared, for example, by preparing various glass raw materials to obtain a glass batch, melting this glass batch, refining and homogenizing the resulting molten glass, and molding it into a predetermined shape. It can be made by

It is preferable to use a reducing agent as a part of the glass raw material in the manufacturing process of the glass forming the frame member 6 . By doing so, the Fe ³⁺ contained in the glass is reduced, and the transmittance of deep ultraviolet rays is improved. Materials such as wood powder, carbon powder, metal aluminum, metal silicon, and aluminum fluoride can be used as the reducing agent, and among these, metal silicon and aluminum fluoride are preferred.

Metallic silicon is preferably used as a part of the raw material for glass in the manufacturing process of the glass constituting the frame member 6, and the amount thereof added is 0.001 to 3% by mass, 0.001 to 3% by mass, and 0.001 to 3% by mass, based on the total mass of the glass batch. 005 to 2% by weight, 0.01 to 1% by weight, particularly 0.03 to 0.1% by weight. If the amount of metal silicon added is too small, the Fe ³⁺ contained in the glass will not be reduced, and the transmittance in deep ultraviolet rays will tend to decrease. On the other hand, if the amount of metal silicon added is too large, the glass tends to be colored brown.

It is also preferable to use aluminum fluoride (AlF ₃ ) as a part of the glass raw material _. 4% by mass, 0.1 to 3% by mass, 0.2 to 2% by mass, and 0.3 to 1% by mass are preferred. On the other hand, if the added amount of aluminum fluoride is too large, F ₂ gas may remain in the glass as bubbles. If the amount of aluminum fluoride added is too small, the Fe ³⁺ contained in the glass will not be reduced, and the transmittance in deep ultraviolet rays will tend to decrease.

In the manufacturing process of the glass that constitutes the frame member 6, it is preferable to form the glass plate from which the frame member 6 is based by a down-draw method, particularly an overflow down-draw method. In the overflow down-draw method, molten glass is overflowed from both sides of a heat-resistant gutter-shaped structure, and while the overflowed molten glass is joined at the lower end of the gutter-shaped structure, it is stretched downward to form a glass sheet. It is a way to In the overflow down-draw method, the surface to be the surface of the glass sheet does not come into contact with the gutter-like structure and is formed in a free surface state. Therefore, it becomes easy to produce a thin glass plate, and variations in plate thickness can be reduced without polishing the surface. As a result, the manufacturing cost of the glass plate can be reduced. The structure and material of the gutter-like structure are not particularly limited as long as desired dimensions and surface accuracy can be achieved. In addition, the method of applying a force during the downward stretching is not particularly limited. For example, a method of stretching by rotating a heat-resistant roll having a sufficiently large width in contact with the glass may be adopted, or a plurality of pairs of heat-resistant rolls are brought into contact only near the end face of the glass. You may employ|adopt the method of letting and extending|stretching.

In addition to the overflow downdraw method, for example, a slot downdraw method, a redraw method, a float method, etc., can also be adopted as a method of forming the glass that constitutes the frame member 6 .

As the glass constituting the frame member 6, for example, BU-41 manufactured by Nippon Electric Glass Co., Ltd. can be used. The coefficient of thermal expansion of BU-41 in the temperature range of 30 to 380°C is, for example, 42×10 ^-7 /°C. As the glass forming the frame member 6, quartz glass may be used in addition to the BU-41.

The thickness (vertical dimension) of the frame member 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, Most preferably 0.1-0.2 mm larger.

The lid member 7 is made of quartz glass. "Quartz glass" in this embodiment includes fused silica and synthetic silica. The coefficient of thermal expansion of fused silica glass in the temperature range of 30 to 380° C. is, for example, 6.3×10 ⁻⁷ /° C., and the coefficient of thermal expansion of synthetic silica glass in the temperature range of 30 to 380° C. is, for example, 4.0×. 10 ^-7 /°C. Further, in the present embodiment, the lid member 7 is a plate-like body in which both the upper surface 7a and the lower surface 7b are flat.

The thickness (vertical dimension) of the lid member 7 is preferably 0.1 to 1.0 mm, more preferably 0.2 to 0.8 mm, and more preferably 0.3 to 0.6 mm. Most preferred.

The welded part 9 is formed by laser welding. Specifically, the welded portion 9 is formed by melting at least one of the frame member 6 and the lid member 7 in the laser irradiation region and then solidifying the melted portion. In other words, it is preferable that the welded portion 9 is made of at least one material of the frame member 6 and the lid member 7 and does not substantially contain materials other than the frame member 6 and the lid member 7 .

A plurality of welded portions 9 (two in the illustrated example) are formed concentrically around the through hole H, but only one may be formed. Although the plurality of welded portions 9 are separated from each other in the radial direction of the through hole H, they may overlap in the radial direction. Each welded portion 9 is configured in a quadrangular ring shape in a plan view, but is not limited to this, and may be configured in an annular shape or other ring shape.

The welded portion 9 is formed continuously across the frame member 6 and the lid member 7 in the thickness direction. In this embodiment, there is no interface between the frame member 6 and the lid member 7 inside the welded portion 9 . Of course, an interface may remain between the frame member 6 and the lid member 7 inside the welded portion 9 .

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

The maximum residual stress in the planar direction of the welded portion 9 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 is the birefringence (unit: nm) near the joint on a glass plate having a size of 10 mm × 10 mm or more, using a birefringence measuring device: ABR-10A manufactured by Uniopt. and the maximum value when converted to the residual stress in the plane direction. Further, by optically measuring birefringence, that is, by 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 deviatoric stress F (MPa) generated by the residual stress is , F=D/CW. "D" is the optical path difference (nm), "W" is the distance (cm) passed by the polarized wave, and "C" is the photoelastic constant (proportionality constant), usually 20 to 40 (nm/ cm)/(MPa). The residual stress in the planar direction includes tensile stress and compressive stress, and the absolute values of both are evaluated here.

The sealing material layer 5 joins the base material 3 and the frame member 6 while being interposed between the upper surface 3 a of the base material 3 and the lower end opening (lower end surface 6 b ) of the frame member 6 . By joining the base material 3 and the frame material 6 with the sealing material layer 5 , an airtight structure surrounding the electronic component 2 is formed by both the base material 3 and the protective cap 4 . The sealing material layer 5 is made of a sealing material containing a glass material. The sealing material layer 5 in this embodiment is produced by applying a sealing material paste produced by kneading a sealing material and a vehicle onto the substrate 3, drying, removing the binder, and sintering. The details of the sealing material layer 5 and the sealing material will be described in the electronic device manufacturing method below.

3 to 8 illustrate the manufacturing method of the electronic device 1 described above.

The manufacturing method of the electronic device 1 includes a first bonding step of bonding the frame material 6 and the lid material 7 to obtain the protective cap 4, and bonding the base material 3 on which the electronic component 2 is mounted and the protective cap 4. and a second bonding step.

In the first joining step, first, as shown in FIG. 3, the frame member 6 and the lid member 7 are prepared. Next, as indicated by a chain double-dashed line in the figure, the upper end surface 6a of the frame member 6 and the lower surface 7b of the lid member 7 are brought into direct contact. After that, as shown in FIG. 4, the laser irradiation device 10 irradiates the contact portion between the frame member 6 and the cover member 7 with a focused laser L. As shown in FIG. The laser L is irradiated from at least one side of the frame member 6 and the lid member 7 . In this embodiment, the laser L is irradiated from the lid member 7 side. As a result, the contact portion is welded to form the welded portion 9 , and the frame member 6 and the lid member 7 are joined by the welded portion 9 .

The arithmetic average roughness Ra of the upper end surface 6a of the frame member 6 and the lower surface 7b of the lid member 7 is preferably 2.0 nm or less, more preferably 1.0 nm or less, and 0.5 nm or less. It is more preferably 0.2 nm or less, and most preferably 0.2 nm or less. Arithmetic mean roughness Ra means a value measured by a method conforming to JIS B0601:2001. In this way, the frame member 6 and the lid member 7 are brought into close contact with each other due to the intermolecular force (optical contact) between the bonding surfaces, so that the handleability before laser bonding is improved.

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

The wavelength of the laser L is not particularly limited as long as it can pass through the glass member, but for example, it is preferably 400 to 1600 nm, more preferably 500 to 1300 nm. 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 focused diameter of the laser L is preferably 50 μm or less, more preferably 30 μm or less, and even more preferably 20 μm or less.

The repetition frequency of the laser L is required to cause continuous heat accumulation, specifically preferably 100 kHz or more, more preferably 200 kHz or more, and 500 kHz or more. is more preferred.

In addition, it is preferable to use a technique (burst mode) in which one pulse is divided into multiple parts and the pulse intervals are further shortened. As a result, heat accumulation is likely to occur, and the welded portion 9 can be stably formed.

As shown in FIG. 5, the laser L scans around the through-hole H so as to draw a circular trajectory T along the through-hole H. In this case, the laser L is scanned so that the irradiation area R overlaps the circular orbit T and makes one round of the circular orbit T. As shown in FIG. Alternatively, the laser L is scanned so as to go around the circular orbit T multiple times. When forming a plurality of welded portions 9 concentrically, a plurality of circular orbits T for scanning the laser L are also set concentrically.

In addition, the joint may be formed in a frame shape by intersecting four straight lines so as to surround the through hole H. By using such a form, it is possible to manufacture a plurality of protective caps 4 at once, so that the manufacturing efficiency of the electronic device 1 can be improved.

In the second bonding step, as preparation for bonding the base material 3 and the frame material 6, the sealing material layer 5 is interposed between the base material 3 and the lower end opening (lower end surface 6b) of the frame material 6. A joining preparation step (FIGS. 6 and 7), and a joining book for joining the base material 3 and the lower end opening of the frame member 6 by irradiating the sealing material layer 5 with a laser L to soften and deform it after the joining preparation step. and a step (FIG. 8).

In the bonding preparation process, the base material 3 is first coated with a sealing material paste. The sealing material paste is applied to a portion of the upper surface 3a of the base material 3 that will be overlaid on the lower end surface 6b of the frame member 6 later. In this embodiment, the sealing material paste is applied along the edge of the upper surface 3a of the base material 3. As shown in FIG. Application of the sealing material paste to the substrate 3 can be performed by a well-known method. For example, screen printing, dispenser application, or the like can be used.

The sealing material that is kneaded with the vehicle when producing the sealing material paste is generally a composite powder containing glass powder and refractory filler powder, and if necessary, a laser absorbing material such as a coloring pigment. It may be added. If the thermal expansion coefficient of the glass powder is low (for example, the thermal expansion coefficient is 90×10 ⁻⁷ /° C. or less in the temperature range of 30° C. to 300° C.), the glass powder alone may be used as the sealing material. be. The sealing material is a material that softens and flows (softens and deforms) by laser irradiation in the subsequent main joining process, thereby integrating the base material 3 and the frame material 6 . A vehicle generally refers to a mixture of an organic resin and a solvent, that is, a viscous liquid in which the organic resin is dissolved, and a sealing material paste is obtained by dispersing the sealing material in the vehicle. A surfactant, a thickening agent, etc. may be added to the vehicle, if necessary.

As the sealing material, the glass powder alone may be used as described above, but it is preferable to use a composite powder containing the glass powder and the refractory filler powder. As the composite powder, it is preferable to use a composite powder containing 60 to 100 vol% glass powder and 0 to 40 vol% refractory filler powder, and 65 to 95 vol% glass powder and 5 to 35 vol% It is more preferable to use a composite powder containing a refractory filler powder. The refractory filler powder is added to facilitate matching of the coefficient of thermal expansion of the sealing material with that of the substrate 3 and the frame member 6 . As a result, it is possible to prevent damage to the electronic device 1 due to excessive stress remaining around the sealing material layer 5 after the main bonding step. On the other hand, if the content of the refractory filler powder is too large, the content of the glass powder is relatively small, so that the surface smoothness of the sealing material layer 5 is reduced, and the sealing material layer 5 is sealed to the upper surface 3a of the substrate 3. The adhesion with the material layer 5 is lowered, and the sealing strength tends to be lowered.

The softening point of the sealing material is preferably 550°C or lower, more preferably 520°C or lower, and particularly preferably 480°C or lower. If the softening point of the sealing material is too high, it becomes difficult to improve the surface smoothness of the sealing material layer 5 . In addition, since it is necessary to excessively raise the temperature of the sealing material (sealing material layer 5) when irradiating the laser L in the main joining process, the base material 3 and the frame material 6 are likely to be damaged due to this. . Although the lower limit of the softening point of the sealing material is not particularly set, considering the thermal stability of the glass powder, the softening point of the sealing material is preferably 350° C. or higher. Here, the "softening point" corresponds to the fourth inflection point when measured with a macro-type DTA device.

The glass powder is preferably bismuth-based glass from the viewpoint of increasing the sealing strength of the sealing material layer 5 (bonding strength between the base material 3 and the frame member 6). Further, the bismuth-based glass has a glass composition of 28 to 60% Bi ₂ O ₃ , 15 to 37% B ₂ O ₃ , 0 to 30% ZnO, CuO+MnO (total amount of CuO and MnO) 1 to 1%. It preferably contains 40%. The reason why the content range of each component is limited as described above will be explained below. In addition, in description of content of each component about glass powder, % display represents mol% unless otherwise specified.

Bi ₂ O ₃ is the main ingredient for lowering the softening point. The content of Bi ₂ O ₃ is preferably 28-60%, more preferably 33-55%, particularly preferably 35-45%. If the content of Bi ₂ O ₃ is too small, the softening point becomes too high, and softening fluidity tends to decrease. On the other hand, if the content of Bi ₂ O ₃ is too large, the glass tends to devitrify when irradiated with the laser L in the main joining step, and this devitrification tends to reduce softening fluidity. .

B ₂ O ₃ is an essential component as a glass-forming component. The content of B ₂ O ₃ is preferably 15-37%, more preferably 19-33%, particularly preferably 22-30%. If the B ₂ O ₃ content is too low, the formation of a glass network becomes difficult, and the glass tends to devitrify when irradiated with the laser L. On the other hand, if the content of B ₂ O ₃ is too high, the viscosity of the glass increases and softening fluidity tends to decrease.

ZnO is a component that enhances devitrification resistance. The content of ZnO is preferably 0-30%, more preferably 3-25%, still more preferably 5-22%, and particularly preferably 5-20%. If the ZnO content is too high, the balance of components in the glass composition is lost, and the devitrification resistance tends to decrease.

CuO and MnO are components that greatly enhance the laser absorption ability. The total amount of CuO and MnO is preferably 1-40%, more preferably 3-35%, even more preferably 10-30%, and particularly preferably 15-30%. If the total amount of CuO and MnO is too small, the laser absorbing power tends to decrease. On the other hand, if the total amount of CuO and MnO is too large, the softening point becomes too high, and even if the laser L is irradiated, the glass becomes difficult to soften and flow. Moreover, the glass becomes thermally unstable, and the glass tends to devitrify when the laser L is irradiated. The CuO content is preferably 1 to 30%, particularly preferably 10 to 25%. The content of MnO is preferably 0-25%, more preferably 1-25%, and particularly preferably 3-15%.

In addition to the above components, other components listed below, for example, may be added as the glass composition.

SiO ₂ is a component that enhances water resistance. The content of SiO ₂ is preferably 0-5%, more preferably 0-3%, even more preferably 0-2%, and particularly preferably 0-1%. If the SiO ₂ content is too high, the softening point may unduly increase. In addition, the glass tends to devitrify during the laser irradiation in the main joining step.

Al ₂ O ₃ is a component that enhances water resistance. The content of Al ₂ O ₃ is preferably 0-10%, 0.1-5%, particularly 0.5-3%. If the Al ₂ O ₃ content is too high, the softening point may unduly increase.

Li ₂ O, Na ₂ O and K ₂ O are components that reduce devitrification resistance. Therefore, the contents of Li ₂ O, Na ₂ O and K ₂ O are preferably 0 to 5%, 0 to 3%, and particularly preferably 0 to less than 1%.

MgO, CaO, SrO and BaO are components that increase devitrification resistance, but also components that increase the softening point. Therefore, the contents of MgO, CaO, SrO and BaO are preferably 0 to 20%, 0 to 10%, and particularly 0 to 5%, respectively.

Fe ₂ O ₃ is a component that enhances devitrification resistance and laser absorption ability. The content of Fe ₂ O ₃ is preferably 0-10%, more preferably 0.1-5%, particularly preferably 0.4-2%. If the content of Fe ₂ O ₃ is too high, the composition of the glass will be out of balance, and the resistance to devitrification will tend to decrease.

Sb ₂ O ₃ is a component that enhances devitrification resistance. The content of Sb ₂ O ₃ is preferably 0-5%, particularly preferably 0-2%. If the content of Sb ₂ O ₃ is too large, the component balance of the glass composition is lost, and the devitrification resistance tends to decrease.

As the glass powder contained in the sealing material, not only the bismuth-based glass but also zinc-based borate-based glass, silver-phosphate-based glass, or tellurium-based glass can be used. Zinc borate glass is characterized by a lower coefficient of thermal expansion than bismuth glass. Compared to bismuth-based glass, silver phosphate-based glass and tellurium-based glass are more likely to soften and flow at low temperatures, and can reduce thermal strain that occurs after irradiation with the laser L. Therefore, they have high thermal reliability and mechanical reliability. It has the characteristic that it can be enhanced. Furthermore, silver phosphate glass and tellurium glass can increase the mechanical strength of the sealing material layer 5 by mixing refractory filler powder, as with bismuth glass. The coefficient of thermal expansion can be lowered.

The zinc borate glass should contain 40 to 80% SiO ₂ +ZnO, 5 to 25% B ₂ O ₃ , 0 to 20% Al ₂ O ₃ and 0 to 20% MgO as the glass composition. is preferred.

The content of SiO ₂ +ZnO (total amount of SiO ₂ and ZnO) is preferably 40-80%, more preferably 45-70%, and particularly preferably 50-65%. If the content of SiO ₂ +ZnO is too small, the weather resistance tends to be lowered and vitrification becomes difficult. On the other hand, if the content of SiO ₂ +ZnO is too high, the softening point may unduly increase.

The content of SiO ₂ is preferably 15-45%, more preferably 20-40%, particularly preferably 22-36%. If the content of SiO ₂ is too low, the weather resistance tends to decrease and vitrification becomes difficult. On the other hand, if the SiO ₂ content is too high, the softening point may unduly increase.

The content of ZnO is preferably 20-55%, more preferably 25-50%, and particularly preferably 30-45%. If the ZnO content is too low, the devitrification property during melting becomes strong, making it difficult to obtain a homogeneous glass. On the other hand, if the ZnO content is too high, the weather resistance tends to decrease.

The molar ratio SiO ₂ /ZnO (value obtained by dividing the content of SiO ₂ by the content of ZnO) is preferably 0.6 to 2.0, more preferably 0.7 to 1.8, particularly preferably 0.7 to 1.8. 8 to 1.7. If the molar ratio SiO ₂ /ZnO is too small, the glass tends to undergo phase separation and the weather resistance tends to decrease. On the other hand, if the molar ratio SiO ₂ /ZnO is too large, the softening point may unduly increase.

B ₂ O ₃ is a network-forming component of glass and a component that enhances softening fluidity. The content of B ₂ O ₃ is preferably 5-25%, more preferably 7-23%, particularly preferably 8-20%. If the content of B ₂ O ₃ is too small, the crystallinity will be strong, which will impair the softening fluidity and make it difficult to secure the sealing strength. On the other hand, when the content of B ₂ O ₃ is too high, the weather resistance tends to decrease.

Al ₂ O ₃ is a component that stabilizes the glass. The content of Al ₂ O ₃ is preferably 0-20%, more preferably 2-18%, particularly preferably 5-15%. If the content of Al ₂ O ₃ is too small, vitrification becomes difficult. On the other hand, if the Al ₂ O ₃ content is too high, the softening point may unduly increase.

MgO is a component that lowers the viscosity of glass. By containing a predetermined amount of MgO, low-temperature sintering becomes possible even when a large amount of SiO ₂ is contained. The content of MgO is preferably 0-20%, more preferably 3-18%, particularly preferably 5-15%. If the MgO content is too low, the softening point may unduly increase. On the other hand, if the MgO content is too high, the coefficient of thermal expansion tends to be too high.

In addition to _the above components, _glass compositions may include other components (e.g., _Li2O , _Na2O , _K2O , CaO, SrO, BaO, _MnO2 , _Ta2O5 , _Nb2O5 , _CeO2 , Sb ₂ O ₃ etc.) may be contained up to 7% (preferably up to 3%).

On the other hand, from an environmental point of view, it is preferable that the glass composition does not substantially contain lead components (for example, PbO, etc.) and that it does not substantially contain F and Cl.

The silver phosphate glass should contain 10 to 50% Ag ₂ O, 10 to 35% P ₂ O ₅ , 3 to 25% ZnO, and 0 to 30% transition metal oxide in terms of mol % of the glass composition. is preferred.

Ag ₂ O is a component that lowers the melting point of glass and increases water resistance because it is difficult to dissolve in water. The content of Ag ₂ O is preferably 10-50%, more preferably 20-40%. If the content of Ag ₂ O is too small, the viscosity of the glass increases, and the fluidity and water resistance of the glass tend to decrease. On the other hand, when the Ag ₂ O content is too high, vitrification becomes difficult.

P ₂ O ₅ is a component that lowers the melting point of glass. Its content is preferably 10 to 35%, more preferably 15 to 25%. If the P ₂ O ₅ content is too low, vitrification becomes difficult. On the other hand, if the content of P ₂ O ₅ is too large, the weather resistance and water resistance tend to deteriorate.

ZnO is a component that enhances resistance to devitrification, and its content is preferably 3-25%, 5-22%, and particularly preferably 9-20%. If the ZnO content is outside the above range, the component balance of the glass composition is impaired, and devitrification resistance tends to decrease.

A transition metal oxide is a component having laser absorption properties, and its content is preferably 0-30%, 1-30%, and particularly preferably 3-15%. If the transition metal oxide content is too high, the devitrification resistance tends to decrease.

By adding CuO as a component, the laser absorption characteristics can be enhanced. The CuO content is preferably 0 to 30%, 1 to 30%, particularly 3 to 15%. If the CuO content is too high, the component balance of the glass composition is impaired, and the devitrification resistance tends to decrease.

TeO ₂ is a glass-forming component and a component that lowers the melting point of glass. The content of TeO ₂ is preferably 0-40%, more preferably 10-30%.

Nb ₂ O ₅ is a component that enhances water resistance. The content of Nb ₂ O ₅ is preferably 0-25%, more preferably 1-12%. If the content of Nb ₂ O ₅ is too high, the viscosity of the glass increases and the fluidity tends to decrease.

Li ₂ O, Na ₂ O and K ₂ O are components that reduce devitrification resistance. The content of Li ₂ O, Na ₂ O and K ₂ O is thus respectively 0-5%, 0-3% and in particular 0-1%.

MgO, CaO, SrO and BaO are components that increase devitrification resistance, but also components that increase the softening point. The contents of MgO, CaO, SrO and BaO are thus respectively 0-20%, 0-10% and especially 0-5%.

The tellurium-based glass preferably contains 20 to 80% TeO ₂ , 0 to 25% Nb ₂ O ₅ and 0 to 40% transition metal oxide in terms of mol % of glass composition.

TeO ₂ is a glass-forming component and a component that lowers the melting point of glass. The content of TeO ₂ is preferably 20-80%, more preferably 40-75%.

Nb ₂ O ₅ is a component that enhances water resistance. The content of Nb ₂ O ₅ is preferably 0-25%, 1-20%, particularly 5-15%. If the content of Nb ₂ O ₅ is too high, the viscosity of the glass increases and the fluidity tends to decrease.

A transition metal oxide is a component having laser absorption properties, and its content is preferably 0 to 40%, 5 to 30%, and particularly preferably 15 to 25%. If the transition metal oxide content is too high, the devitrification resistance tends to decrease.

Among transition metal oxides, CuO is highly effective in enhancing laser absorption characteristics and is also highly effective in enhancing thermal stability. The CuO content is preferably 0 to 40%, 5 to 30%, particularly 15 to 25%. If the CuO content is too high, the component balance of the glass composition is impaired, and the devitrification resistance tends to decrease.

The average particle size D ₅₀ of the glass powder is preferably less than 15 μm, more preferably 0.5-10 μm, particularly preferably 1-5 μm. The softening point of the glass powder decreases as the average particle size _D50 of the glass powder decreases. Here, "average particle diameter _D50 " refers to a value measured on a volume basis by a laser diffraction method.

The refractory filler powder preferably contains one or more selected from cordierite, zircon, tin oxide, niobium oxide, zirconium phosphate ceramic, willemite, β-eucryptite, and β-quartz solid solution. , especially β-eucryptite or cordierite. These refractory filler powders have a low coefficient of thermal expansion, high mechanical strength, and good compatibility with glass powder.

The average particle size D ₅₀ of the refractory filler powder is preferably less than 2 μm, in particular greater than or equal to 0.1 μm and less than 1.5 μm. If the average particle diameter _D50 of the refractory filler powder is too large, the surface smoothness of the sealing material layer 5 tends to decrease, and the average thickness of the sealing material layer 5 tends to increase. The irradiation accuracy of the laser L at .

The 99% particle size D ₉₉ of the refractory filler powder is preferably less than 5 μm and less than or equal to 4 μm, in particular greater than or equal to 0.3 μm and less than or equal to 3 μm. If the 99% particle diameter D ₉₉ of the refractory filler powder is too large, the surface smoothness of the sealing material layer 5 tends to decrease, and the average thickness of the sealing material layer 5 tends to increase. The irradiation accuracy of is likely to decrease. Here, "99% particle size D ₉₉ " refers to a value measured on a volume basis by a laser diffraction method.

The sealing material may further contain a laser absorbing material in order to enhance the laser absorption properties, but the laser absorbing material has the effect of promoting devitrification of the glass. Furthermore, if a laser absorbing material is introduced, the laser absorption characteristics of the sealing material become too high, and the difference in laser absorption characteristics between the base material 3 and the sealing material layer 5 tends to increase. Therefore, the content of the laser absorbing material in the sealing material layer 5 is preferably 10% by volume or less, 5% by volume or less, 1% by volume or less, and 0.5% by volume or less, and particularly preferably not substantially contained. . Cu-based oxides, Fe-based oxides, Cr-based oxides, Mn-based oxides, spinel-type composite oxides thereof, and the like can be used as the laser absorber.

The coefficient of thermal expansion of the sealing material is preferably 35×10 ^-7 to 90×10 ^-7 /°C, 40×10 ^-7 to 70×10 ^-7 /°C, particularly 45×10 ^-7 to 65×10 -7 ^{. 7} /°C. In this way, the thermal expansion coefficient of the sealing material matches that of the base material 3 and the frame member 6, and the stress remaining in the sealing region (around the sealing material layer 5) is reduced. The "thermal expansion coefficient" is a value measured in a temperature range of 30 to 200°C with a TMA (push rod type thermal expansion coefficient measurement) device.

Specific examples of sealing materials are given here. A first example is a composite powder material of bismuth-based glass powder and β-eucryptite (BF-0901 manufactured by Nippon Electric Glass Co., Ltd., thermal expansion coefficient 4.9 ppm/°C at 30 to 380°C). A second example is a zinc borate glass powder (GP-014 manufactured by Nippon Electric Glass Co., Ltd., thermal expansion coefficient at 30 to 380° C. of 4.3 ppm/° C.).

The sealing material paste is usually prepared by kneading and dispersing the sealing material and vehicle with a three-roller or the like. The vehicle contains an organic resin and a solvent as described above. The organic resin is added for the purpose of adjusting the viscosity of the paste.

As the organic resin added to the vehicle, acrylic acid ester (acrylic organic resin), ethyl cellulose, polyethylene glycol derivatives, nitrocellulose, polymethylstyrene, polyethylene carbonate, polypropylene carbonate, methacrylic acid ester, etc. can be used. Solvents used in vehicles include N,N'-dimethylformamide (DMF), α-terpineol, higher alcohols, γ-butyl lactone (γ-BL), tetralin, terpene, butyl carbitol 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, dimethylsulfoxide (DMSO), N-methyl-2-pyrrolidone and the like can be used.

After the application of the sealing material paste to the base material 3 is completed, the applied film of the sealing material paste is dried. The coating film may be dried naturally, but from the viewpoint of drying efficiency, it is preferably dried in an electric oven or a drying oven.

Next, the dried film obtained by drying the coating film is subjected to binder removal treatment by heating the entire substrate 3 using an electric furnace or the like, and is heated at a temperature equal to or higher than the softening point of the glass powder to soften and flow. Then, a sealing material layer 5 having high surface smoothness is obtained. The dry film can also be sintered by irradiating it with a laser beam.

The average thickness of the sealing material layer 5 is preferably less than 10.0 µm, particularly preferably 1.0 µm or more and less than 7.0 µm. Even if the thermal expansion coefficients of the sealing material layer 5, the base material 3, and the frame material 6 are inconsistent, the smaller the average thickness of the sealing material layer 5, the more after irradiation with the laser L (after the main bonding step) Residual stress in the sealing area can be reduced. Also, the irradiation accuracy of the laser L in the main joining process can be improved. As a method for regulating the average thickness of the sealing material layer 5 as described above, a method of applying a thin layer of sealing material paste and a method of polishing the surface of the sealing material layer 5 can be mentioned.

The average width of the sealing material layer 5 (the average dimension in the horizontal direction of the sealing material layer 5 shown in FIG. 6) is preferably less than 3500 μm, less than 1200 μm, particularly 150 μm or more and less than 800 μm. By narrowing the average width of the sealing material layer 5, the stress remaining in the sealing region after the laser L irradiation can be reduced. Furthermore, the width of the edge of the base material 3 (where it overlaps with the frame member 6) can be narrowed, and the effective area functioning as a device with an airtight structure can be increased.

After the sealing material layer 5 shown in FIG. 6 is formed on the base material 3 as described above, the upper surface 3a of the base material 3 and the frame material are then formed as shown by the two-dot chain line in FIG. 6 and the lower end surface 6a of 6 are overlapped with the sealing material layer 5 interposed therebetween. This completes the bonding preparation process.

When the bonding preparation process is completed, next, the main bonding process is executed. In this bonding step, the substrate 3 is first preheated prior to the laser L irradiation. In preheating, the substrate 3 is heated to a temperature of, for example, 250.degree. C. to 450.degree. As a result, heat conduction to the base material 3 side can be inhibited when the laser L is irradiated, so that the sealing material layer 5 can be softened and deformed efficiently. However, the preheating of the base material 3 is not essential and may be omitted.

When the preheating of the base material 3 is completed, next, as shown in FIG. The laser L is irradiated from the frame member 6 side through which the laser L is transmitted between the base material 3 and the frame member 6 . As a result, the sealing material layer 5 is softened and deformed to join the base material 3 and the frame member 6 . When irradiating the laser L, the sealing material layer 5 sandwiched between the base material 3 and the lower end opening of the frame member 6 is pressed from above and below. This makes it possible to promote the softening deformation of the sealing material layer 5 . However, the pressing of the sealing material layer 5 is not essential and may be omitted.

The arithmetic average roughness Ra of each of the upper surface 3a of the base material 3 and the lower end surface 6b of the frame member 6 is preferably 2.0 nm or less, more preferably 1.0 nm or less, and 0.5 nm or less. It is more preferably 0.2 nm or less, and most preferably 0.2 nm or less.

Various lasers can be used as the laser L with which the sealing material layer 5 is irradiated. In particular, semiconductor lasers, YAG lasers, CO ₂ lasers, excimer lasers, and infrared lasers are preferred because they are easy to handle.

The beam shape of the laser light when the laser L is irradiated is not particularly limited. The beam shape is generally circular, elliptical, or rectangular, but other shapes may be used. Moreover, the beam diameter of the laser light during irradiation with the laser L is preferably 0.3 to 3.5 mm.

The atmosphere in which the laser L is irradiated is not particularly limited, and may be an air atmosphere or an inert atmosphere such as a nitrogen atmosphere. When the main joining process is completed as described above, the electronic device 1 is manufactured. The sealing material layer 5 provided in the electronic device 1 contains, as a glass material, the glass powder originally contained in the sealing material.

Here, it is also possible to apply the following modifications to the above embodiment. In the above-described embodiment, in manufacturing the electronic device 1, after the frame member 6 and the lid member 7 are joined, the base material 3 and the frame member 6 are joined by executing the joining preparation step and the main joining step. However, the order of bonding may be reversed. That is, the frame member 6 and the lid member 7 may be joined after the base member 3 and the frame member 6 are joined by performing the joining preparation step and the joining main step.

1 electronic device 2 electronic component 3 base material 5 sealing material layer 6 frame material 7 lid material L laser

Claims

an electronic component, a base material on which the electronic component is mounted, a frame member made of glass that surrounds the electronic component with one end opening being joined to the base material, and a frame member that closes the other end opening of the frame member and a lid member directly bonded to the frame member in a method for manufacturing an electronic device comprising:
A bonding preparation step of interposing a sealing material containing a glass material between the base material and the opening at one end of the frame material;
After the bonding preparation step, a main bonding step of bonding the base material and the one end opening of the frame member by irradiating the sealing material with a laser to soften and deform it;
A method of manufacturing an electronic device, comprising:
The method of manufacturing an electronic device according to claim 1, wherein the softening point of the sealing material is 550°C or lower.
3. The sealing material according to claim 1, wherein the sealing material has a thermal expansion coefficient of 35×10 -7 /°C to 90×10 -7 /°C in a temperature range of 30°C to 200°C. A method of manufacturing an electronic device.
The glass material contains 28 to 60% Bi 2 O 3 , 15 to 37% B 2 O 3 , 0 to 30% ZnO, and 1 to 40% CuO+MnO in terms of mol % of the glass composition. The method for manufacturing an electronic device according to any one of claims 1 to 3.
The sealing material further contains at least one refractory filler powder selected from cordierite, zircon, tin oxide, niobium oxide, zirconium phosphate ceramic, willemite, β-eucryptite, and β-quartz solid solution. 5. The method for manufacturing an electronic device according to claim 1, comprising:
The method for manufacturing an electronic device according to any one of claims 1 to 5, wherein the base material is heated before the main bonding step.
7. The electronic device according to any one of claims 1 to 6, wherein in the main joining step, the laser is irradiated while the sealing material is pressed by the base material and one end opening of the frame member. Production method.
The method of manufacturing an electronic device according to any one of claims 1 to 7, wherein the bonding preparation step and the bonding main step are performed after bonding the frame member and the lid member.
The method of manufacturing an electronic device according to any one of claims 1 to 7, wherein the frame member and the lid member are joined after the main joining step is performed.
When joining the frame member and the lid member, the contact portion between the other end opening of the frame member and the lid member is in contact with each other, and the contact portion between the two is irradiated with a laser beam. 10. The method of manufacturing an electronic device according to claim 1, wherein the cover material is directly welded to the cover material.
an electronic component, a base material on which the electronic component is mounted, a frame member made of glass that surrounds the electronic component with one end opening being joined to the base material, and a frame member that closes the other end opening of the frame member and a lid member directly joined to the frame member,
An electronic device, wherein the base material and the frame material are joined via a sealing material containing a glass material.