Lid member, package, and glass substrate

Abstract

To achieve both improved transmittance and ensured strength of a glass lid member used in a package including a light-emitting element.SOLUTION: A lid member 4 includes a plate-like frame part 7 and a projecting part 8 protruding from the frame part 7. The projecting part 8 includes a base portion 10 and a top portion 12. The thickness of the top portion 12 is smaller than the thickness of the base portion 10.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a lid for a package, a package having a lid, and a glass substrate for forming the lid. [Background technology]

[0002] For example, Patent Document 1 discloses a package that includes a base (substrate) on which a light-emitting element (LED element) is mounted, a dome-shaped lid member (light-transmitting cover) fixed to the base so as to cover the light-emitting element, and an adhesive that joins the base and the lid member. In this package, the lid member is configured in a dome shape, thereby ensuring a space between the lid member and the base to accommodate the light-emitting element. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-66169 Summary of the Invention [Problem to be solved by the invention]

[0004] In conventional packages, it is preferable to make the thickness of the lid member as thin as possible to increase the transmittance of the lid member. However, if the lid member is too thin, its strength decreases and it may break.

[0005] Therefore, the present invention has as its technical object to simultaneously improve the transmittance of the cover member and ensure its strength. [Means for solving the problem]

[0006] The present invention is intended to solve the above-mentioned problems, and is characterized in that it provides a glass lid member used in a package including a light-emitting element, the lid member having a plate-shaped frame portion and a protrusion protruding from the frame portion, the protrusion portion having a base portion and a top portion, and the thickness of the top portion being thinner than the thickness of the base portion.

[0007] According to this configuration, by making the thickness of the top of the protrusion of the lid member thinner than the thickness of the base, it is possible to increase the transmittance of the protrusion. In addition, since the thickness of the base of the protrusion is thicker than the thickness of the top, it is possible to increase the strength of the base compared to the top. Therefore, it is possible to achieve both improved transmittance and ensure strength of the lid member.

[0008] In the above-described lid member, the ratio (Tmin / Tmax) of the thickness (Tmin) of the top portion to the thickness (Tmax) of the base portion is preferably 0.08 or more and 0.9 or less. If the ratio (Tmin / Tmax) is greater than 0.9, the transmittance at the top portion decreases, and if it is less than 0.08, the strength of the glass at the top portion cannot be ensured. Therefore, it becomes impossible to improve the transmittance of the lid member while ensuring the strength of the top portion at the same time.

[0009] In the lid member according to the present invention, the protrusion has an inner surface and an outer surface, and the surface roughness Ra of the inner surface is preferably 1 nm or less. By specifying the upper limit of the surface roughness Ra of the inner surface to 1 nm or less, it is possible to suppress diffuse reflection of light emitted by the light-emitting element inside the package on the inner glass surface, thereby suppressing a decrease in transmittance. Furthermore, the surface roughness Ra of the outer surface is preferably 1 nm or less. By specifying the upper limit of the surface roughness Ra of the outer surface as described above, it is possible to suppress diffuse reflection of light emitted by the light-emitting element inside the package on the outer glass surface, thereby suppressing a decrease in transmittance. Note that as long as the surface roughness Ra of the inner and outer surfaces is 0.01 nm or more, diffuse reflection of light emitted by the light-emitting element inside the package on the inner and outer glass surfaces will not affect the transmittance. Therefore, a surface roughness below this range is not necessarily required due to the increased cost of processing the glass surface.

[0010] The lid member according to the present invention may include a curved connecting portion that connects the base portion and the frame portion, thereby increasing the strength of the portion of the lid member between the base portion of the protrusion and the frame portion as much as possible.

[0011] The connecting portion has a first curved surface and a second curved surface that connect the base portion and the frame portion, and it is preferable that the radius of curvature of the first curved surface is 0.5 mm or more and 5 mm or less, and the radius of curvature of the second curved surface is 0.5 mm or more and 5 mm or less.

[0012] The frame preferably has a first main surface and a second main surface, and a metal layer is preferably formed on the first main surface. By using this metal layer when forming a bonding material on the lid member, the bonding material can be well fitted to the metal layer, resulting in bonding the lid member and the base member together.

[0013] A buffer film may be formed between the first main surface of the frame and the metal layer. By using this buffer film, residual stress generated inside the lid member due to the difference in thermal expansion coefficient between the lid member and the bonding material when the lid member and the base are bonded can be alleviated, and damage to the lid member caused by the residual stress can be suppressed.

[0014] A bonding portion may be formed on the metal layer at a portion opposite to the portion in contact with the buffer film. By providing the bonding portion, the lid member and the base body can be bonded airtightly.

[0015] The package according to the present invention comprises a base that supports a light emitting element and the above-described lid member, and thus it is possible to improve the transmittance of the lid member while ensuring its strength.

[0016] The present invention is intended to solve the above-mentioned problems, and is a glass substrate for use in a package including a light-emitting element to manufacture a lid member, the glass substrate comprising a plate-shaped frame portion and a plurality of protrusions protruding from the frame portion, the protrusions comprising a base portion and a top portion, and the thickness of the top portion being thinner than the thickness of the base portion.

[0017] According to this configuration, the thickness of the top of the protrusion is made thinner than the thickness of the base, thereby increasing the transmittance of the protrusion. In addition, the thickness of the base of the protrusion is made thicker than the thickness of the top, so the strength of the base can be made higher than that of the top. Therefore, it is possible to achieve both improved transmittance and ensure strength of the lid member manufactured from this glass substrate. [Effects of the Invention]

[0018] According to the present invention, it is possible to improve the transmittance of the cover member while ensuring its strength. [Brief explanation of the drawings]

[0019] [Figure 1] FIG. [Figure 2] FIG. [Figure 3] FIG. [Figure 4] FIG. [Figure 5] FIG. 1 is a cross-sectional view of a cover member; [Figure 6] FIG. [Figure 7] 10A and 10B are cross-sectional views showing a preparation step in the package manufacturing method. [Figure 8] 10A and 10B are cross-sectional views showing a preparation step in the package manufacturing method. [Figure 9] 10A to 10C are cross-sectional views showing a bonding step in the package manufacturing method. [Figure 10] 10A to 10C are cross-sectional views showing a bonding step in the package manufacturing method. [Figure 11] 1 is a cross-sectional view showing a glass substrate for manufacturing a lid member for a package. [Figure 12] FIG. 10 is a cross-sectional view showing another example of the cover member. [Figure 13] FIG. 10 is a plan view showing another example of the cover member. [Figure 14] FIG. 10 is a plan view showing another example of the cover member. [Figure 15]10A and 10B are cross-sectional views showing another example of a preparation step in the manufacturing method of a package. [Figure 16] FIG. 10 is a cross-sectional view showing another example of a package. [Figure 17] FIG. 10 is a cross-sectional view showing another example of a package. [Figure 18] FIG. 1 is a side view showing a package breaking strength tester. DETAILED DESCRIPTION OF THE INVENTION

[0020] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the drawings. Figures 1 to 17 show an embodiment of a lid member, a package, and a glass substrate according to the present invention.

[0021] As shown in Figures 1 and 2, the package 1 includes a base 2, a light-emitting element 3 supported by the base 2, a lid member 4 that covers the base 2 and the light-emitting element 3, and a sealing portion 5 that hermetically joins the base 2 and the lid member 4.

[0022] 3 and 4 show the base 2 before the lid member 4 is bonded to it. The base 2 has a first main surface 2a that supports the light-emitting element 3, a second main surface 2b located opposite to the first main surface 2a, and a metal layer 6 formed on the first main surface 2a.

[0023] Examples of materials for the substrate 2 include ceramics such as aluminum nitride, aluminum oxide, silicon carbide, and silicon nitride, glass ceramics obtained by mixing and sintering these ceramics with glass powder, and alloys such as Fe-Ni-Co alloys, Cu-W alloys, and Kovar (registered trademark).

[0024] 4, the metal layer 6 has a frame shape that surrounds the light-emitting element 3. The metal layer 6 has a rectangular shape, but is not limited to this shape. The metal layer 6 may also be configured in a circular shape so as to surround the light-emitting element 3, for example.

[0025] The metal layer 6 includes three layers, namely, an underlayer, an intermediate layer, and a surface layer, in that order from the first main surface 2a side. Examples of metals used for the underlayer include Cr, Ta, W, Ti, Mo, Ni, and Pt. Examples of metals used for the intermediate layer include Ni, Pt, and Pd. Examples of metals used for the surface layer include Au, Sn, Ag, Ni, and Pt. The metal used for the metal layer 6 may be a single metal or an alloy.

[0026] Examples of methods for forming the metal layer 6 on the first main surface 2a of the substrate 2 include film formation methods such as sputtering, vacuum deposition, ion-assisted or ion-plating vacuum deposition, and CVD.

[0027] The light-emitting element 3 is fixed to the first main surface 2a of the base 2. In this embodiment, the package 1 uses an ultraviolet irradiating LED as the light-emitting element 3, but the light-emitting element 3 according to the present invention is not limited to this embodiment, and an infrared LED or a visible light LED can also be used.

[0028] 5 and 6 show the lid member 4 before being bonded to the base 2. The lid member 4 is manufactured by molding a portion of a glass plate. The glass used for the lid member 4 is preferably alkali-free glass, borosilicate glass, aluminosilicate glass, quartz glass, or crystallized glass. Alkali-free glass, borosilicate glass, or aluminosilicate glass can achieve both high transmittance and high processability during molding. Quartz glass can have significantly high transmittance in the ultraviolet range while maintaining processability during molding. Crystallized glass can achieve both high transmittance and high breaking strength.

[0029] When the glass is borosilicate glass, aluminosilicate glass, or alkali-free glass, the glass composition preferably contains, in mass %, SiO2: 50-75%, Al2O3: 1-25%, B2O3: 0-30%, Li2O + Na2O + K2O: 0-20%, and MgO + CaO + SrO + BaO: 0-20%. Glass compositions within the above composition ranges fall under these glass types.

[0030] In the case of glass-ceramics, the glass composition preferably contains, by mass %, SiO2: 60-80%, Al2O3: 3-30%, Li2O+Na2O+K2O: 1-20%, MgO+CaO+SrO+BaO: 5-20%, and is a low-thermal-expansion glass-ceramics in which β-quartz solid solution or β-spodumene precipitates as crystals from the inside of the glass. Here, low thermal expansion means that the value of the thermal expansion coefficient is -10 × 10 in the temperature range of 30 to 300°C. -7 ~20×10 -7 / ℃.

[0031] As shown in FIGS. 2 and 5, the cover member 4 includes a plate-shaped frame portion 7, a dome-shaped protruding portion 8 protruding from the frame portion 7, and a connecting portion 9 connecting the frame portion 7 and the protruding portion 8 together.

[0032] The frame 7 has, for example, a constant thickness, but is not limited to this embodiment. The thickness of the frame 7 is, for example, 0.2 mm or more and 2 mm or less. The frame 7 has a first main surface 7a and a second main surface 7b located opposite the first main surface 7a. The surface roughness (arithmetic mean roughness) Ra of the first main surface 7a is preferably 1 nm or less, more preferably 0.5 nm or less, and even more preferably 0.3 nm or less. The surface roughness Ra of the second main surface 7b is preferably 1 nm or less, more preferably 0.5 nm or less, and even more preferably 0.3 nm or less.

[0033] The protrusion 8, together with the first main surface 2a of the base 2, forms a space for accommodating the light-emitting element 3. The protrusion 8 is formed at the center of the frame 7, but is not limited to this. The protrusion 8 has an inner surface 8a configured as a concave curved surface and an outer surface 8b configured as a convex curved surface. The protrusion 8 also includes a base 10, a midpoint 11, and a top 12. The base 10 is configured integrally with the connecting portion 9. The midpoint 11 is located between the base 10 and the top 12. The base 10 is the portion where a line (hereinafter referred to as the "first line") L1 normal to the top 12 is drawn, and a line (hereinafter referred to as the "second line") L2 drawn along the second main surface 7b of the frame portion 7 is drawn from the intersection P between this first line L1 and the line (hereinafter referred to as the "second line") L2, and a line (hereinafter referred to as the "third line") L3 that forms an angle of 5° with the second line L2 intersects with the protrusion 8.

[0034] The outer diameter D of the protrusion 8 (base 10) is, for example, 2 mm or more and 150 mm or less. The height H of the protrusion 8 (the distance from the second main surface 7b of the frame 7 to the apex 12) is, for example, 0.5 mm or more and 80 mm or less. As shown in FIG. 5, the thickness of the protrusion 8 gradually decreases from the base 10 to the apex 12. Therefore, the thickness Tmin of the apex 12 is thinner than the thickness Tmax of the base 10.

[0035] The thickness Tmax of the base 10 is, for example, 0.19 mm or more and 1.9 mm or less. The thickness Tmin of the top 12 is, for example, 0.15 mm or more and 1.0 mm or less. The ratio Tmin / Tmax of the thickness Tmax of the base 10 to the thickness Tmin of the top 12 is preferably 0.08 or more and 0.9 or less, more preferably 0.1 or more and 0.8 or less, and even more preferably 0.2 or more and 0.5 or less.

[0036] The inner surface 8a and the outer surface 8b are configured as continuously curved surfaces from the base 10 to the top 12. The surface roughness Ra of the inner surface 8a is preferably 1 nm or less, more preferably 0.5 nm or less, and even more preferably 0.3 nm or less. The surface roughness Ra of the outer surface 8b is preferably 1 nm or less, more preferably 0.5 nm or less, and even more preferably 0.3 nm or less.

[0037] 2 and 5, the connecting portion 9 has a curved shape to connect the base portion 10 and the frame portion 7. The connecting portion 9 has a first curved surface 9a that connects the first main surface 7a of the frame portion 7 and the inner surface 8a of the protruding portion 8, and a second curved surface 9b that connects the outer surface 8b of the protruding portion 8 and the second main surface 7b of the frame portion 7.

[0038] The radius of curvature of the first curved surface 9a is larger than the radius of curvature of the second curved surface 9b. The radius of curvature of the first curved surface 9a is preferably 0.5 mm or more and 5 mm or less, more preferably 1 mm or more and 4 mm or less. The radius of curvature of the second curved surface 9b is preferably 0.5 mm or more and 5 mm or less, more preferably 1 mm or more and 4 mm or less. The surface roughness Ra of the first curved surface 9a is preferably 1 nm or less, more preferably 0.5 nm or less, and even more preferably 0.3 nm or less. The surface roughness Ra of the second curved surface 9b is preferably 1 nm or less, more preferably 0.5 nm or less, and even more preferably 0.3 nm or less.

[0039] As shown in FIGS. 2, 5, and 6, a buffer film 13, a metal layer 14, and a bonding portion 15 are formed on the first main surface 7a of the frame portion 7. The lid member 4 has a flat frame portion 7, which allows a large region (area) to be secured on the first main surface 7a for forming the buffer film 13, the metal layer 14, and the bonding portion 15. Furthermore, because the lid member 4 has a flat frame portion 7, the frame portion 7 can be gripped with a gripping tool or the like during the process of manufacturing the package 1 without touching the protrusions 8 or the base 10, which affect the optical properties of the package 1. This improves the handleability during the manufacturing process of the package 1, and increases the manufacturing efficiency of the package 1.

[0040] The buffer film 13 serves to relieve stress that occurs in the frame portion 7 of the lid member 4 when the base body 2 and the lid member 4 are joined at the joint portion 15. The buffer film 13 is made of an oxide film.

[0041] The Young's modulus of the oxide constituting the buffer film 13 is preferably 250 GPa or less, more preferably 200 GPa or less, even more preferably 150 GPa or less, and particularly preferably 100 GPa or less. By specifying the upper limit in this way, the buffering properties of the buffer film 13 can be improved, and the effect of alleviating stress caused by the difference in thermal expansion coefficient between the joint 15 and the lid member 4 (frame 7) can be obtained. The thermal expansion coefficient of the frame 7 is smaller than that of the joint 15. The thermal expansion coefficient of the frame 7 is also smaller than that of the base 2.

[0042] As shown in FIGS. 5 and 6, the buffer film 13 is formed on the first main surface 7a of the frame portion 7 of the cover member 4. As shown in FIG. 6, the buffer film 13 has a frame shape. The buffer film 13 is configured in a quadrangular shape, but is not limited to this shape and may be circular or another shape. The buffer film 13 has a multilayer film structure that alternates between, for example, a silicon oxide film (SiO2) as a first film and a hafnium oxide film (HfO2) as a second film. The material of the buffer film 13 is not limited to that of this embodiment.

[0043] The thickness of the buffer film 13 is preferably 0.1 μm or more and 1 μm or less, and more preferably 0.2 μm or more and 0.8 μm or less. By specifying the lower limit in this way, the buffering properties of the buffer film 13 can be further improved, and the effect of alleviating stress caused by the difference in thermal expansion coefficient between the joint portion 15 and the cover member 4 (frame portion 7) can be obtained. Furthermore, by specifying the upper limit in this way, the manufacturing cost of the buffer film 13 can be reduced.

[0044] When the light-emitting element 3 is an LED for ultraviolet irradiation, the buffer film 13 also functions as an anti-reflection film that prevents reflection of ultraviolet light. That is, the buffer film 13 has a multilayer structure in which low-refractive index layers (silicon oxide films in this embodiment) and high-refractive index layers (hafnium oxide films in this embodiment) are alternately stacked. The transmittance of the buffer film 13 to ultraviolet light (wavelength 280 nm) is preferably 90% or more.

[0045] As shown in Figures 5 and 6, the metal layer 14 is formed so as to overlap the buffer film 13. As shown in Figure 6, the metal layer 14 has a rectangular frame shape corresponding to the shape of the metal layer 6 of the base 2. The shape of the metal layer 14 is not limited to this embodiment. The metal layer 14 may have various frame shapes, including a circular shape. The metal layer 14 includes three layers, namely, an underlayer, an intermediate layer, and a surface layer, in that order from the buffer film 13 side. Note that by making the width of the metal layer 14 narrower than the width of the buffer film 13, the influence of stress due to the difference in thermal expansion coefficient between the joint 15 and the lid member 4 can be reduced.

[0046] Examples of metals used for the underlayer include Cr, Ta, W, Ti, Mo, Ni, and Pt. When Cr is used for the underlayer, the Young's modulus of the underlayer is 279 GPa. Examples of metals used for the intermediate layer include Ni, Pt, and Pd. Examples of metals used for the surface layer include Au, Sn, Ag, Ni, and Pt. The metal used for the metal layer 14 may be a single metal or an alloy.

[0047] 5 and 6, the bonding portion 15 is configured in a layered form so as to overlap the metal layer 14. As shown in FIG. 5, the bonding portion 15 is in contact with a portion of the metal layer 14 opposite to the portion in contact with the buffer film 13. As shown in FIG. 6, the bonding portion 15 has a rectangular frame shape so as to correspond to the shapes of the buffer film 13 and the metal layer 14. The shape of the bonding portion 15 is not limited to this embodiment, and may be a circle or any other frame shape.

[0048] The bonding portion 15 is made of a metallic bonding material. Commercially available solder materials or brazing filler metals can be used as the metallic bonding material. Examples of metallic bonding materials include Au-Sn alloys, Pb-Sn alloys, Au-Ge alloys, and Sn-Ni alloys. By making the width of the bonding portion 15 narrower than the width of the buffer film 13, the influence of stress due to the difference in thermal expansion coefficient between the bonding portion 15 and the lid member 4 can be reduced. In this embodiment, a case where an Au-Sn alloy is used as the metallic bonding material will be described.

[0049] For example, when forming the joint 15 on the first main surface 7a of the frame portion 7 using a screen printing method, the first main surface 7a is configured as a flat surface, which increases the degree of freedom in the width and position of the joint 15 formed on this first main surface 7a.

[0050] The sealing portion 5 is formed by integrally joining the metal layer 6 of the base 2 and the metal layer 14 of the lid member 4 at a joint 15 .

[0051] Next, a description will be given of a method for manufacturing the package 1. This method includes a preparation step of preparing the base body 2 and the lid member 4, and a joining step of joining the base body 2 and the lid member 4 together.

[0052] In the preparation step, after the metal layer 6 is formed on the first main surface 2a of the base 2, the light emitting element 3 is mounted on this first main surface 2a.

[0053] In the preparation process, after the cover member 4 is manufactured by forming the protrusion 8 on the glass plate, the buffer film 13, the metal layer 14, and the bonding portion 15 are formed on the first main surface 7a side of the frame portion 7.

[0054] A method for forming the protrusions 8 on the lid member 4 (a method for manufacturing the lid member 4) will be described below with reference to FIGS.

[0055] 7 shows a manufacturing device for the lid member 4. The manufacturing device 16 includes a support table 17 that supports a glass sheet GS, a mask member 18 that is placed over the glass sheet GS supported on the support table 17, and a heat source 19 that thermally deforms a portion of the glass sheet GS to form the protrusion 8 of the lid member 4. The manufacturing device 16 further includes a pressing member 20 that presses the support table 17 and the mask member 18 in a direction that brings them closer to each other, and an external force generator 21 that applies an external force to a portion of the glass sheet GS.

[0056] The support base 17 has a support portion 17a that supports the glass sheet GS and a space portion 17b that has an opening surrounded by the support portion 17a and allows for thermal deformation of part of the glass sheet GS. The support portion 17a of the support base 17 has a support surface that supports the main surface of the glass sheet GS. The opening in this embodiment has a circular opening edge E1, but may have an opening edge of a polygonal shape such as a triangular or rectangular shape, or an elliptical shape, for example.

[0057] Space 17b of support base 17 may be formed by a through-hole or a recess having an inner bottom. Space 17b of support base 17 is configured so that the entire protrusion 8 of cover member 4 can be molded in a non-contact state. Examples of materials that form support base 17 include metals and ceramics.

[0058] In addition to the above configuration, a support jig for supporting the glass sheet GS may be provided in the space 17b in order to form the shape of the lid member 4 with high precision. The support jig is made of metal or ceramics. As mentioned above, it is preferable to form the entire protrusion 8 of the lid member 4 in a non-contact state, but by improving the quality of the surface of the support jig that comes into contact with the glass sheet GS (reducing surface roughness and surface waviness), the lid member 4 can be formed with high precision even when a support jig is used.

[0059] 7, the mask member 18 has a through hole 18a. The through hole 18a of the mask member 18 in this embodiment has a circular inner peripheral edge E2, but may have an inner peripheral edge that is polygonal, such as triangular or rectangular, or elliptical.

[0060] The support base 17 and the mask member 18 are configured so that at least a part of the inner periphery E2 of the through hole 18a in the mask member 18 is located inside the opening edge E1 of the support base 17. Specifically, the support base 17 and the mask member 18 are configured so that the entire inner periphery E2 of the through hole 18a in the mask member 18 is located inside the opening edge E1 of the support base 17.

[0061] When the opening area of ​​the opening of the support base 17 is taken as 100%, the cross-sectional area of ​​the through hole 18a of the mask member 18 is preferably 95% or less, and more preferably 80%. At least a part of the inner peripheral edge E2 of the through hole 18a in the mask member 18 is preferably positioned 1 mm or more inward from the opening edge E1 of the support base 17, and more preferably 3 mm or more inward.

[0062] The mask member 18 is preferably made of a material having a thermal conductivity of 1 [W / (m·K)] or less at 600°C. Ceramics, for example, are suitable as materials for the mask member 18. The thickness of the mask member 18 is preferably 1 mm or more. The mask member 18 of this embodiment has an outer shape that covers the entire outer periphery of the glass plate GS.

[0063] The heat source 19 is arranged to heat the glass sheet GS from the mask member 18 side. The heat source 19 in this embodiment is a burner that sprays a flame FL toward the glass sheet GS. By using a burner, the glass sheet GS can be softened relatively quickly. The heating method of the heat source 19 may be, for example, resistance heating or laser heating. The heat source 19 may also be configured by combining heat sources of different heating methods.

[0064] The pressing member 20, for example, presses the mask member 18 toward the support base 17. Examples of a pressing mechanism that presses the pressing member 20 include a fluid cylinder and a linear actuator. Note that the pressing member 20 can also be configured to press the support base 17 against the fixed mask member 18.

[0065] An exhaust device, for example, can be used as the external force generator 21. The exhaust device creates a negative pressure in the space 17b of the support base 17 by discharging gas present in the space 17b of the support base 17. This causes a portion of the glass sheet GS to be sucked into the space 17b of the support base 17, thereby promoting thermal deformation of the portion of the glass sheet GS. A pump using a Venturi mechanism, for example, is suitable as the exhaust device.

[0066] The external force generator 21 is not limited to an exhaust device, and may be a high-pressure gas generator that sprays high-pressure gas toward a portion of the glass sheet GS from the mask member 18 side. This pressurizes the portion of the glass sheet GS toward the space 17b of the support base 17, thereby promoting thermal deformation of the portion of the glass sheet GS. Alternatively, a pump and a high-pressure gas generator may be used in combination to promote thermal deformation of the portion of the glass sheet GS.

[0067] The method for manufacturing the lid member 4 using the manufacturing apparatus 16 configured as described above includes a forming step for thermally deforming a part of the glass sheet GS.

[0068] 7 and 8, in the forming process, first, a mask member 18 is placed on top of a glass sheet GS supported by a support stand 17. In this case, the support stand 17 and the mask member 18 are placed such that at least a part of the inner peripheral edge E2 of the through hole 18a of the mask member 18 is located inside the opening edge E1 of the support stand 17. Thereafter, the pressing member 20 presses the support stand 17 and the mask member 18 in a direction to bring them closer to each other. This makes it possible to prevent the glass sheet GS sandwiched between the support stand 17 and the mask member 18 from shifting in position.

[0069] Next, in the forming step, the glass sheet GS is heated from the mask member 18 side by the heat source 19. As a result, a part of the glass sheet GS is thermally deformed, and the protrusion 8 is formed.

[0070] In the above-described forming process, the opening edge E1 of the support base 17 can be covered with the mask member 18. This allows the connecting portion 9 of the lid member 4 to be formed by thermal deformation of the glass sheet GS along the inner peripheral edge E2 of the through hole 18a of the mask member 18. In other words, the connecting portion 9 of the lid member 4 is formed without contacting the support base 17. Through this forming process, the lid member 4 having the frame portion 7, the protruding portion 8, and the connecting portion 9 is formed.

[0071] In addition to the above, the method of forming the protrusions 8 on the lid member 4 (the method of manufacturing the lid member 4) can also be a method in which the glass sheet GS is placed on a metal or ceramic mold having recesses, and the glass sheet GS is hot-pressed using a metal or ceramic mold having protrusions that fit into the recesses. The heating temperature in this hot-pressing is preferably equal to or higher than the yield point of the glass sheet GS, and more preferably equal to or higher than the softening point of the glass sheet GS.

[0072] When the molding process is completed, the buffer film 13, the metal layer 14, and the bonding portion 15 are formed on the first main surface 7a of the frame portion 7 in this order.

[0073] First, silicon oxide films and hafnium oxide films are alternately stacked on the first main surface 7a of the frame 7 to form the buffer film 13. Examples of methods for forming the buffer film 13 include sputtering, vacuum deposition, ion-assisted or ion-plating vacuum deposition, and CVD.

[0074] Next, a metal layer 14 is formed so as to overlap the buffer film 13. Examples of methods for forming the metal layer 14 include film formation methods such as sputtering, vacuum deposition, ion-assisted or ion-plating vacuum deposition, and CVD.

[0075] Thereafter, the bonding portion 15 is formed so as to overlap the metal layer 14. The bonding portion 15 includes a step (coating step) of applying, for example, a paste-like metal-based bonding material to the metal layer 14 so as to overlap the metal layer 14. Specific examples of the coating step include a printing method using a mask (screen printing method), a coating method using a dispenser, and the like.

[0076] The bonding portion 15 is not limited to the above method, and for example, a molded body of a metal-based bonding material formed in advance into a predetermined frame shape may be placed so as to overlap the metal layer 14 on the first main surface 7a of the frame portion 7.

[0077] Once the metallic bonding material for the bonding portion 15 has been applied to the first main surface 7a of the frame portion 7, a heat treatment process is carried out to fix the metallic bonding material to the metal layer 14 on the first main surface 7a. The heat treatment process includes a heating process and a cooling process.

[0078] In the heating step, the lid member 4 is heated using a heating device such as a reflow furnace, thereby melting the metal bonding material. The heating step may be performed, for example, in a furnace filled with nitrogen. In the heating step, the lid member 4 is heated to a temperature of 300°C or higher.

[0079] In the cooling step, the metal-based bonding material melted on the first main surface 7a of the frame 7 is solidified by cooling. The cooling step preferably includes slow cooling, in which the temperature is maintained within a range of 150°C to 300°C for a period of 2 minutes to 30 minutes. In the cooling step, stress is generated in the cover member 4 due to the difference in thermal expansion coefficient between the frame 7 and the bonding portion 15, but the buffer film 13 can relieve this stress.

[0080] 9, in the bonding step, the lid member 4 is placed on the base body 2. Specifically, the first main surface 7a of the frame portion 7 of the lid member 4 is placed opposite to the base body 2, and the bonding portion 15 is brought into contact with the metal layer 6 formed on the first main surface 2a of the base body 2.

[0081] 10, the pressing member 22 is placed on the frame portion 7 of the cover member 4. The pressing member 22 has a weight 23 and a support member 24 that supports the weight 23. The weight 23 and the support member 24 are made of, for example, metal or ceramic.

[0082] The support member 24 has a first support portion 24a that supports the weight 23 and a second support portion 24b that supports the first support portion 24a.

[0083] The first support portion 24a has a support surface (upper surface) on which the weight 23 is placed. The second support portion 24b includes a plurality of rod-shaped members. The second support portion 24b protrudes downward from the lower surface of the first support portion 24a.

[0084] The second support portion 24b has a contact portion 25 that comes into contact with the frame portion 7 of the cover member 4. The contact portion 25 is configured in a pointed shape. The contact portion 25 comes into contact with the second main surface 7b of the frame portion 7 so as to correspond to the position of the buffer film 13 of the frame portion 7.

[0085] Pressing member 22 presses lid member 4 while standing on its own on lid member 4, as each contact portion 25 of multiple second support portions 24b comes into contact with frame portion 7. Pressing lid member 4 with pressing member 22 allows joint portion 15 formed on frame portion 7 of lid member 4 and metal layer 6 formed on first main surface 2a of base 2 to be tightly attached to each other.

[0086] Thereafter, the metal layer 6 and the bonding portion 15 are heated while being pressed together (heating step). As a result, the metallic bonding material of the bonding portion 15 is melted. In this heating step, the pointed contact portion 25 of the second support portion 24b comes into contact with the frame portion 7 of the cover member 4, so that the contact area between the contact portion 25 and the frame portion 7 can be made as small as possible. This makes it possible to minimize heat transfer from the frame portion 7 to the second support portion 24b of the pressing member 22.

[0087] Thereafter, the molten metal-based bonding material is cooled and solidified (cooling process). During the cooling process, stress is generated in the frame 7 due to the difference in thermal expansion coefficient between the base 2 and the frame 7 of the lid member 4. In this case, the buffer film 13 deforms to relieve this stress. This makes it possible to reduce damage to the frame 7.

[0088] When the cooling step is completed, the sealing portion 5 is formed by integrally joining the metal layer 6 of the base 2 and the metal layer 14 of the lid member 4 at the joint 15. In this way, the package 1 that is airtight is completed.

[0089] 11 shows an example of a glass substrate for manufacturing the lid member 4. The glass substrate G includes a frame 7 and a plurality of protrusions 8 protruding from the frame 7. Each of the protrusions 8 has the same configuration as the protrusions 8 of the lid member 4 in the above embodiment. Each of the protrusions 8 is formed by thermally deforming a large glass plate GS at multiple locations using the above manufacturing apparatus 16. By cutting this glass substrate G along the cutting lines CL, multiple lid members each having the protrusions 8 and the frame 7 can be efficiently manufactured.

[0090] 12 shows another example of a lid member. In this example, the lid member 4 includes a frame 7, a plurality of protrusions 8 protruding from the frame 7, and a buffer film 13, a metal layer 14, and a bonding portion 15 formed on the first main surface 7a of the frame 7. Each component of the lid member 4 has the same configuration as the lid member 4 in the above embodiment. When a plurality of light-emitting elements 3 are mounted on the base 2, this lid member 4 can individually seal each light-emitting element 3 with the plurality of protrusions 8 and each buffer film 13, etc.

[0091] 13 and 14 are plan views showing other examples of the lid member. In this example, the lid member 4 has a plurality of protrusions 8 arranged in multiple rows and columns. The lid member 4 shown in FIG. 13 has a plurality of protrusions 8 configured in a circular shape in plan view. On the other hand, the lid member 4 shown in FIG. 14 has a plurality of protrusions 8 configured in a rectangular shape in plan view. For the lid member 4 having a plurality of protrusions 8 arranged in multiple rows and columns, scribe lines are made on the smooth surface between adjacent protrusions 8, and the lid member 4 is fractured along the scribe lines, or diced by a blade dicing method or laser ablation method, thereby obtaining a plurality of lid members and lid members of any shape.

[0092] 15 shows another example of a method for manufacturing a lid member (a preparation step in a package manufacturing method). This example shows a step of forming a bonding portion 15 on a glass substrate G on which a buffer film 13 and a metal layer 14 have been formed. Specifically, a case will be described in which the glass substrate G is fixed to a support device 26 when forming the bonding portion 15 by screen printing.

[0093] The supporting device 26 includes a supporting plate 27 that supports the glass substrate G, and a suction table 29 that supports the supporting plate 27 .

[0094] The support plate 27 is configured to be detachable from the suction stand 29. The support plate 27 has openings 28 into which the protruding portions 8 and connecting portions 9 of the glass substrate G can be inserted. By inserting the protruding portions 8 and connecting portions 9 into the openings 28 with the protruding portions 8 of the glass substrate G facing downward, the support plate 27 can support only the frame portion 7 of the glass substrate G without coming into contact with the protruding portions 8 and connecting portions 9.

[0095] The suction table 29 includes a support portion 30 that supports the support plate 27 and a suction port 31 for fixing the glass substrate G to the support plate 27. The support portion 30 has a support surface 30a that supports the peripheral edge of the support plate 27.

[0096] The suction stand 29 has a space 29a between the support plate 27 supported by the support portion 30 and the suction port 31. The suction port 31 is connected to a suction device (exhaust device) such as a pump (not shown).

[0097] The suction table 29, with the support plate 27 on which the glass substrate G is placed supported by the support portions 30, exhausts gas present in the space 29a through the suction ports 31, thereby creating a negative pressure in the space 29a. As a result, the glass substrate G is sucked into the space 29a through the openings 28 of the support plate 27, and is fixed to the support plate 27. Thereafter, a paste-like metallic bonding material for the bonding portion 15 is applied by screen printing so as to overlap the metal layer 14 of the glass substrate G.

[0098] By supporting the glass substrate G by the supporting device 26 as described above, it becomes possible to form the bonding portion 15 with high precision.

[0099] Fig. 16 shows another example of a package. The package 1 in this example includes a base 2 on which a plurality of light-emitting elements 3 are mounted, and the lid member 4 shown in Fig. 12. The lid member 4 individually seals each of the light-emitting elements 3 mounted on the base 2 with a plurality of protrusions 8 and a sealing portion 5.

[0100] Figure 17 shows another example of a package. The package 1 in this example differs from the example shown in Figures 1 and 2 in the configuration of the lid member 4. The lid member 4 has antireflection films 32a, 32b that cover the entire inner surface (first main surface 7a of the frame 7, inner surface 8a of the protrusion 8, and first curved surface 9a of the connecting portion 9) and outer surface (second main surface 7b of the frame 7, outer surface 8b of the protrusion 8, and second curved surface 9b of the connecting portion 9). The antireflection films 32a, 32b include a first antireflection film 32a that covers the inner surface of the lid member 4 and a second antireflection film 32b that covers the outer surface of the lid member 4.

[0101] Each of the anti-reflection films 32a and 32b is formed by various methods such as a film forming method such as sputtering or vacuum deposition, or a spray coating method.

[0102] Each of the anti-reflection films 32a, 32b has a multilayer structure that alternates between a first silicon dioxide (SiO2) film and a second hafnium dioxide (HfO2) film. The thickness of each of the anti-reflection films 32a, 32b is preferably 0.1 μm to 1 μm, more preferably 0.2 μm to 0.8 μm.

[0103] A part of the first antireflection film 32a functions as a buffer film 13 for alleviating stress caused by the difference in thermal expansion coefficient between the frame portion 7 and the bonding portion 15. In other words, the first antireflection film 32a is a film that is integral with the buffer film 13 in the package 1 illustrated in FIGS.

[0104] In the package 1 of this example, the anti-reflection films 32a and 32b formed on the inner and outer surfaces of the lid member 4 can improve the light extraction efficiency of the light emitting element 3 as much as possible.

[0105] With the package 1 (lid member 4) and glass substrate G according to the present embodiment described above, it is possible to increase the transmittance by making the thickness Tmin of the top 12 of the protruding portion 8 of the lid member 4 thinner than the thickness Tmax of the base 10. Furthermore, it is possible to increase the strength of the lid member 4 at this protruding portion 8 by making the thickness Tmax of the base 10 at the protruding portion 8 thicker than the thickness Tmin of the top 12. Therefore, according to the present invention, it is possible to improve the transmittance of the lid member 4 while ensuring its strength.

[0106] In addition to the above, in the lid member 4 according to this embodiment, the frame portion 7 and the protruding portion 8 are connected by the connecting portion 9 having a curved shape, which makes it possible to increase the strength of the lid member 4 at this connecting portion 9. Furthermore, since the protruding portion 8 of the lid member 4 is formed without contacting either the support base 17 of the manufacturing apparatus 16 or the mask member 18, it is possible to minimize the surface roughness Ra of the inner surface 8a and the outer surface 8b. Similarly, the connecting portion 9 of the lid member 4 is also formed without contact, which makes it possible to minimize the surface roughness Ra of the first curved surface 9a and the second curved surface 9b. This allows the lid member 4 to have high transmittance and be resistant to damage.

[0107] The present invention is not limited to the configuration of the above-described embodiment, nor is it limited to the above-described effects. The present invention can be modified in various ways without departing from the spirit of the present invention. [Example]

[0108] Examples of the present invention will be described below, but the present invention is not limited to these examples.

[0109] In order to confirm the effects of the lid member according to the present invention, the inventors prepared lid members according to Example 1 and Comparative Examples 1 and 2, each having a protrusion with an outer diameter of 50 mm and a height of 25 mm, and lid members according to Example 2 and Comparative Examples 3 and 4, each having a protrusion with an outer diameter of 10 mm and a height of 5 mm, and conducted tests for each example. The glass used in the tests was borosilicate glass containing, in mass %, 70% SiO, 20% BO, 5% AlO, 1% CaO, 1% BaO, 2% NaO, and 1% KO.

[0110] The lid members according to Examples 1 to 3 were manufactured by the manufacturing method of the above embodiment, and were configured so that the thickness of the top of the protrusion was thinner than the thickness of the base. On the other hand, the lid members according to Comparative Examples 1 to 4 had protrusions with a constant thickness from the base to the top, which were formed by heating and press-molding a glass substrate. Specifically, the thickness of the protrusion of the lid member according to Comparative Example 1 was the same as the thickness of the base of the protrusion of the lid member according to Example 1. Furthermore, the thickness of the protrusion of the lid member according to Comparative Example 2 was the same as the thickness of the top of the protrusion of the lid member according to Example 1. The thickness of the protrusion of the lid member according to Comparative Example 3 was the same as the thickness of the base of the protrusion of the lid member according to Example 2. Furthermore, the thickness of the protrusion of the lid member according to Comparative Example 4 was the same as the thickness of the top of the protrusion of the lid member according to Example 2.

[0111] A spectrophotometer was used to measure the transmittance of light with a wavelength of 250 nm at the top of the lid member for Examples 1 to 3 and Comparative Examples 1 to 4. Furthermore, a breaking strength tester was used to measure the breaking strength of the base of the lid member for Examples 1 and 2 and Comparative Examples 1 to 4.

[0112] An overview of the breaking strength tester is shown in Figure 18. The breaking strength tester 33 has a support base 35 that supports the lid member 4, and a pressing member 34 that presses the base 10 of the lid member 4. In the breaking strength test, with the lid member 4 supported by the support base 35, the pressing member 34 presses the base 10 of the protrusion 8 of the lid member 4, and the breaking strength (the pressing force of the pressing member 34) is measured. In each example, the breaking strength test was performed using 20 lid members, and values ​​whose average value was equal to or greater than the reference value (50 MPa for Example 1 and Comparative Examples 1 and 2, and 3 MPa for Example 2 and Comparative Examples 3 and 4) were rated as "good," and values ​​below the reference value were rated as "poor."

[0113] The dimensions of the main parts of the lid members in Examples 1 to 3 and Comparative Examples 1 to 4 and the test results are shown in Table 1. In Table 1, the evaluation results of the breaking strength are indicated by "◯" for good and "×" for poor. [Table 1]

[0114] As shown in Table 1, the lid member of the package according to Example 1 had higher transmittance than the lid member of the package according to Comparative Example 1 and was stronger than the lid member of the package according to Comparative Example 2. Furthermore, the lid member of the package according to Example 2 had higher transmittance than the lid member of the package according to Comparative Example 3 and was stronger than the lid member of the package according to Comparative Example 4. Furthermore, the lid member of the package according to Example 3 exhibited high transmittance. The above results demonstrate that the present invention makes it possible to realize a package that achieves both improved transmittance and ensured strength. [Explanation of symbols]

[0115] 1 package 3 Light-emitting element 4 Cover member 7 Frame 7a First principal surface 7b Second principal surface 8 Protrusion 8a Inner surface 8b External surface 9 Connecting part 9a First surface 9b Second surface 10 base 12 Top 13 Buffer membrane 14 Metal layer 15 Joint G Glass substrate Tmax Thickness of the base of the protrusion Tmin Thickness of the top of the protrusion

Claims

1. A glass lid member used in a package including a light emitting element, The device includes a plate-shaped frame portion and a protrusion portion protruding from the frame portion, The protrusion has a base and a top, A cover member characterized in that the thickness of the top portion is thinner than the thickness of the base portion.

2. 2. The lid member according to claim 1, wherein a ratio (Tmin / Tmax) of a thickness (Tmin) of the top portion to a thickness (Tmax) of the base portion is 0.08 or more and 0.9 or less.

3. the protrusion has an inner surface and an outer surface; 3. The cover member according to claim 1, wherein the inner surface has a surface roughness Ra of 1 nm or less.

4. the protrusion has an inner surface and an outer surface; The cover member according to claim 1 , wherein the outer surface has a surface roughness Ra of 1 nm or less.

5. The cover member according to claim 1 , further comprising a curved connecting portion that connects the base portion and the frame portion.

6. the connecting portion has a first curved surface and a second curved surface that connect the base portion and the frame portion, The radius of curvature of the first curved surface is 0.5 mm or more and 5 mm or less, The cover member according to claim 5, wherein the radius of curvature of the second curved surface is 0.5 mm or more and 5 mm or less.

7. the frame portion has a first main surface and a second main surface, The cover member according to claim 1 , wherein a metal layer is formed on the first main surface.

8. The lid member according to claim 7 , wherein a buffer film is formed between the first main surface of the frame and the metal layer.

9. The cover member according to claim 8 , wherein a bonding portion is formed on a portion of the metal layer opposite to a portion in contact with the buffer film.

10. A package comprising: a base supporting a light emitting element; and the lid member according to claim 1 .

11. A glass substrate used for manufacturing a lid member for a package including a light-emitting element, The device includes a plate-shaped frame and a plurality of protrusions protruding from the frame, The protrusion has a base and a top, A glass substrate, wherein the thickness of the top portion is thinner than the thickness of the base portion.

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