Method for manufacturing light-emitting device
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- STANLEY ELECTRIC CO LTD
- Filing Date
- 2025-10-22
- Publication Date
- 2026-06-04
Smart Images
Figure JP2025037116_04062026_PF_FP_ABST
Abstract
Description
Method for manufacturing a light-emitting device
[0001] The present invention relates to a method for manufacturing a light-emitting device equipped with a semiconductor light-emitting element.
[0002] A method for manufacturing a light-emitting device equipped with an ultraviolet light-emitting element is disclosed. For example, Patent Document 1 discloses a method for manufacturing a light-emitting device that includes the steps of mounting an ultraviolet light-emitting element on a flat submount, forming a coating resin made of amorphous fluororesin on the surface of the ultraviolet light-emitting element, and forming a lens made of amorphous fluororesin that covers the ultraviolet light-emitting element and the coating resin.
[0003] WO2019 / 087348 publication
[0004] In the ultraviolet light-emitting device disclosed in Patent Document 1, for example, if an amorphous fluororesin having non-reactive terminal functional groups is used as the coating resin for covering the ultraviolet light-emitting element or as the material for the lens, when the resin material that will become the lens is brought into contact with the surface of the coating resin during manufacturing, the resin material may move significantly, which may result in poor molding or poor adhesion of the lens to the coating resin.
[0005] If such a problem occurs, for example, a defect in the lens molding could reduce the output of the light emitted from the light-emitting device 100, or poor adhesion of the lens to the coating resin could cause a sealing defect in the ultraviolet light-emitting element. In other words, the reliability of the light-emitting device could be reduced.
[0006] This invention has been made in view of the above-mentioned problems, and aims to provide a method for manufacturing a light-emitting device that can improve the reliability of the device.
[0007] The present invention relates to a method for manufacturing a light-emitting device, comprising: a light-emitting element bonding step to form an element-bonded mounting substrate by bonding a light-emitting element that emits ultraviolet light to a pair of mounting electrodes of a device substrate having a flat substrate and a pair of mounting electrodes formed on the upper surface of the substrate; and a sealing body forming step to form a translucent sealing body made of amorphous fluororesin that seals the light-emitting element on the device substrate, wherein the sealing body forming step comprises: a first step of forming a resin layer made of amorphous fluororesin over the upper surface of the device substrate and the surface of the light-emitting element; and a second step, after the first step, of holding the element-bonded mounting substrate in a holding mold so that its bottom surface is in contact with the holding mold, arranging amorphous fluororesin pellets on the periphery of the recess of a molding die having a recess, softening the resin layer and amorphous fluororesin pellets by heating, and closing the holding mold and the molding die to press the element-bonded mounting substrate against the amorphous fluororesin pellets, deforming the amorphous fluororesin pellets to cover the resin layer and form a sealing body.
[0008] This is a perspective view of the light-emitting device according to Example 1. This is a top view of the light-emitting device according to Example 1. This is a cross-sectional view of the light-emitting device according to Example 1. This is a cross-sectional view showing an example of the manufacturing process of the light-emitting device according to Example 1. This is a cross-sectional view showing an example of the manufacturing process of the light-emitting device according to Example 1. This is a cross-sectional view showing an example of the manufacturing process of the light-emitting device according to Example 1. This is a cross-sectional view showing an example of the manufacturing process of the light-emitting device according to Example 1. This is a cross-sectional view showing an example of the manufacturing process of the light-emitting device according to Example 1. This is a cross-sectional view showing an example of the manufacturing process of the light-emitting device according to Example 1. This is a cross-sectional view showing another example of the manufacturing process of the light-emitting device according to Example 1.
[0009] Hereinafter, embodiments of the present invention will be specifically described with reference to the drawings. In the drawings, identical components are denoted by the same reference numerals, and descriptions of redundant components are omitted.
[0010] The configuration of the light-emitting device 100 according to Embodiment 1 will be described using Figures 1 to 3. Figure 1 is a perspective view of the light-emitting device 100. Figure 2 is a top view of the light-emitting device 100. Figure 3 is a cross-sectional view of the light-emitting device 100 shown in Figure 2, along line 3-3. In Figure 3, the vertical direction is the height direction of the light-emitting device 100, and the horizontal direction is the width direction of the light-emitting device 100.
[0011] [Overview of the Light-Emitting Device 100] The light-emitting device 100 is composed of a device substrate 11, a light-emitting element 13 provided on the device substrate 11, and a sealing body 15 that covers and seals the light-emitting element 13 on the device substrate 11.
[0012] Note that in Figure 2, the sealing body 15 is omitted to avoid complicating the illustration. Also, in Figure 2, the center line CL is shown as a line segment that passes through the center of the upper surface of the device substrate 11 and bisects the width of the device substrate 11 in the left-right direction in the figure.
[0013] [Device Substrate 11] First, the configuration of the device substrate 11 will be described. The device substrate 11 is a double-sided wiring board composed of a flat base plate 17 and wiring patterns provided on both main surfaces of the base plate 17.
[0014] The base material 17 is a plate-like body having a rectangular top surface shape. In the light-emitting device 100 of this embodiment, the base material 17 is made of an insulating ceramic made of aluminum nitride (AlN) with excellent heat dissipation properties and a thermal conductivity of 150 to 220 (W / mK). The base material 17 also contains alumina (Al ２ O ３ ), silicon nitride (Si ３ N ４ Ceramics with UV resistance properties such as those mentioned above may also be used.
[0015] Here, the wiring pattern provided on the base material 17 will be described. An element mounting electrode 18 and an annular member 21 are formed on the upper surface of the base material 17. In addition, a mounting electrode 23 is formed on the lower surface of the base material 17.
[0016] The element mounting electrodes 18 are a pair of electrodes provided on the upper surface of the base material 17, approximately in the center, separated from each other by a center line CL. The element mounting electrodes 18 consist of a first element mounting electrode 18A and a second element mounting electrode 18B, each having a rectangular upper surface shape and being the same size. The first element mounting electrode 18A and the second element mounting electrode 18B are provided on the upper surface of the base material 17 so that their long sides face each other.
[0017] The region connecting the outer edges of the first element mounting electrode 18A and the second element mounting electrode 18B is an element mounting region for mounting and bonding the light-emitting element 13. The element mounting electrode 18 is formed by laminating nickel (Ni) and gold (Au) in that order on its upper surface (surface) as protective layers, with copper (Cu) as the base material.
[0018] The annular member 21 is an annular member having an annular upper surface shape. The annular member 21 is provided on the upper surface of the base material 17 such that, in a plan view of the device substrate 11 from above, its inner circle and outer circle are concentric. In other words, the annular member 21 has a uniform band width.
[0019] The annular member 21 surrounds the element mounting electrode 18 while maintaining a distance from it. In other words, the element mounting electrode 18 is positioned in the region of the upper surface of the base material 17 that is surrounded by the annular member 21.
[0020] The annular member 21 is formed by laminating Ni and Au as protective layers on the upper surface of Cu, with Cu as the base material. Alternatively, the annular member 21 may consist only of Cu as the base material without the protective layers. Furthermore, the annular member 21 is not limited to a circular shape; it can also have an ellipse with a center of rotational symmetry, a petal shape with arcs radiating outwards, or a polygon with four or more sides.
[0021] The mounted electrodes 23 are formed on the lower surface of the substrate 17 at a distance from each other, and each electrode is a pair having a rectangular upper surface shape. The mounted electrodes 23 are electrically connected to the element mounting electrode 18 via conductive vias 24 made of conductive metal that penetrate the substrate 17 in the vertical direction in Figure 2.
[0022] Specifically, the mounting electrode 23 consists of a first mounting electrode 23A that is electrically connected to the first element mounting electrode 18A via a conductive via 24, and a second mounting electrode 23B that is electrically connected to the second element mounting electrode 18B via a conductive via 24.
[0023] In the light-emitting device 100 of this embodiment, the mounted electrode 23 has a base material of Cu, with Ni and Au laminated in that order on its lower surface (front surface) as protective layers. The conductive via 24 is made of Cu only as the base material.
[0024] Furthermore, in addition to Cu, other metals such as aluminum (Al) and tungsten (W) can be selected as the base material for each of the element mounting electrodes 18, annular member 21, mounting electrode 23, and conductive via 24 described above. In addition, a combination of titanium (Ti) and Au, or a combination of chromium (Cr) and Au can be selected as the protective layer.
[0025] [Light-emitting element 13] Next, the configuration of the light-emitting element 13 will be described. The light-emitting element 13 is an element that is bonded to the element mounting electrode 18 of the device substrate 11. Here, as described above, the element mounting electrode 18 is provided approximately in the center of the base material 17 in a plan view. Therefore, the light-emitting element 13 is located approximately in the center of the device substrate 11 in a plan view.
[0026] As shown in Figure 3, the light-emitting element 13 is a light-emitting diode (LED) comprising an element substrate 26, a semiconductor structural layer 27 including a light-emitting layer, and p electrodes 28 and n electrodes 29 electrically connected to the semiconductor structural layer 27.
[0027] The element substrate 26 is a flat, translucent substrate with a rectangular top surface. In the light-emitting device 100 of this embodiment, the element substrate 26 is made of an AlN single crystal with a wurzite structure. The element substrate 26 contains sapphire (Al ２ O ３ ) Single crystals can also be used.
[0028] The semiconductor structure layer 27 is a semiconductor crystal layer of an aluminum gallium nitride (AlGaN) crystal system formed across the lower surface of the element substrate 26. The semiconductor structure layer 27 is composed of an n-type semiconductor layer, a light-emitting layer, and a p-type semiconductor layer (all not shown) laminated in this order on the lower surface of the element substrate 26. Note that the exposed surface of the semiconductor structure layer 27 is protected by a protective film such as silicon oxide (SiO ２ ), Al ２ O ３ and the like.
[0029] When the light-emitting element 13 is energized, ultraviolet light with a peak wavelength of 265 nm is emitted from the light-emitting layer of the semiconductor structure layer 27. Each of the p-type semiconductor layer, the light-emitting layer, and the n-type semiconductor layer of the semiconductor structure layer 27 may include a superlattice layer, a quantum well layer, a barrier layer, and the like.
[0030] The p electrode 28 and the n electrode 29 are electrodes electrically connected to the p-type semiconductor layer and the n-type semiconductor layer of the semiconductor structure layer 27, respectively. Each of the p electrode 28 and the n electrode 29 is joined to each of the first element mounting electrode 18A and the second element mounting electrode 18B via a gold-tin (Au—Sn) based joining member 31. That is, the light-emitting element 13 is flip-chip joined to the device substrate 11.
[0031] In the light-emitting device 100, the above-described first element mounting electrode 18A and the first mounting electrode 23A act as anode electrodes, and the second element mounting electrode 18B and the second mounting electrode 23B act as cathode electrodes.
[0032] The ultraviolet light emitted from the light-emitting layer of the semiconductor structure layer 27 due to the energization of the p electrode 28 and the n electrode 29 of the light-emitting element 13 is emitted to the outside of the light-emitting element 13 from the upper surface and the side surface of the element substrate 26. That is, the upper surface of the element substrate 26 is the light-emitting surface of the light-emitting element 13.
[0033] Note that the upper surface of the element substrate 26 of the light-emitting element 13 is a -c plane (non-metal surface) on which N atoms are arranged on the surface. Also, the lower surface of the element substrate 26 is a +c plane (metal surface) on which Al atoms are arranged on the surface. Here, the Al atoms in the +c axis direction are polarized to δ+, and the N atoms in the -c axis direction are polarized to δ-.
[0034] That is, the upper surface of the element substrate 26, which is the light-emitting surface of the light-emitting element 13, is a -c plane (non-metal surface) on which N atoms polarized to δ- are arranged, and is a crystal plane (N atom plane) on which dangling bonds (unbonded hands) of N atoms are exposed. Further, the side surface of the element substrate 26 of the light-emitting element 13 is an a plane and an m plane or a higher-order crystal plane having dangling bonds of Al atoms and N atoms.
[0035] [Sealing body 15] Next, the sealing body 15 will be described. The sealing body 15 is a transparent member that covers the upper surface of the device substrate 11. The sealing body 15 seals and protects the light-emitting element 13 and transmits the emitted light of the light-emitting element 13 to guide the emitted light to the outside of the light-emitting device 100.
[0036] The sealing body 15 is composed of a first sealing member 15A and a second sealing member 15B that covers the first sealing member 15A. The first sealing member 15A is a thin-film transparent resin layer that covers the upper surface of the base material 17, the wiring pattern provided on the base material 17, and the surface of the light-emitting element 13.
[0037] Specifically, as shown in FIG. 3, the first sealing member 15A closely adheres (adheres) to and covers the upper surface of the base material 17, the surfaces of the element mounting electrodes 18, the surface of the light-emitting element 13 (upper surface, side surface, and a part of the lower surface), and the surface of the annular member 21 along their respective shapes. The first sealing member 15A buries the region between the upper surface of the device substrate 11 and the lower surface of the light-emitting element 13.
[0038] The second sealing member 15B is a transparent member having a bullet shape convex upward, formed to cover the entire first sealing member 15A. In other words, the second sealing member 15B has a semi-ellipsoidal shape obtained by rotating a semi-ellipse having the vertical direction in FIG. 3 as the major axis.
[0039] The second sealing member 15B seals the light-emitting element 13 while closely adhering (adhering) to the first sealing member 15A on the device substrate 11. Here, the first sealing member 15A functions as an auxiliary adhesive layer for providing the second sealing member 15B on the device substrate 11.
[0040] Further, here, since the entire surface of the annular member 21 is covered by the first sealing member 15A, for example, when an external force is applied from the left - right direction in the drawing after the manufacturing of the light - emitting device 100, an anchor effect can act to physically fix the sealing body 15 to the device substrate 11. That is, it can resist an external force from the left - right direction in the drawing through the first sealing member 15A adhered (bonded) to the annular member 21. Such a configuration is particularly effective when using an amorphous fluororesin with weak adhesion (adhesive property).
[0041] The second sealing member 15B functions as a convex lens having the major axis of the above - mentioned semi - ellipsoid as the optical axis. In a plan view of the light - emitting device 100 seen from above, the center of the light - emitting element 13, the center of the annular member 21, and the center of the second sealing member 15B are arranged so as to overlap each other.
[0042] Therefore, the light emitted from the light - emitting element 13 has a directivity characteristic of being condensed along the optical axis of the second sealing member 15B and emitted to the outside. When the second sealing member 15B is hemispherical or has a shape of a semi - ellipsoid obtained by rotating a semi - ellipse having the up - down direction in FIG. 3 as the minor axis, the half - value angle of the emitted light of the light - emitting device 100 can be widened.
[0043] The sealing body 15 is made of a thermoplastic amorphous (amorphous) fluororesin (thermoplastic resin) that transmits the light emitted from the light - emitting element 13. The sealing body 15 is, for example, of the S type of Cytop (registered trademark) manufactured by AGC Inc.
[0044] Specifically, the amorphous fluororesin used as the constituent material of the sealing body 15 is, as shown in the following chemical formula 1, a product of the cyclopolymerization of perfluoro(4 - vinyloxy - 1 - butene) (hereinafter also referred to as BVE), which is the main chain, and the terminal functional group is a trifluoromethyl group ( - CF ３ ) having high light resistance to ultraviolet light with a wavelength of 265 nm, which is the emission wavelength of the light - emitting element 13. Such an amorphous fluororesin modified at the terminal or in the middle of the main chain with a perfluorocarbon - based functional group has high light resistance to ultraviolet light with a wavelength of 220 nm to 300 nm. On the other hand, its adhesion (adhesive property) to other substances is weak.
[0045]
[0046] Furthermore, this amorphous fluororesin has a refractive index of 1.34 and a transmittance of 90% or more for ultraviolet light. The light output of the light-emitting device 100 using this amorphous fluororesin as the sealant 15 is improved by more than 1.5 times compared to the light output of a light-emitting device sealed using, for example, a glass cap with a convex space in which the light-emitting element 13 is housed in that space.
[0047] In this embodiment, the light-emitting device 100 uses a wurtzite-structured single-crystal AlN substrate as the element substrate 26 of the light-emitting element 13, and therefore the terminal functional groups are -CF ３ It improves adhesion (chemical bonding) with amorphous fluororesins.
[0048] In detail, the light-emitting element 13 was configured such that its upper surface, i.e., the light-emitting surface (upper surface) of the element substrate 26, is a -c plane (non-metallic surface) where dangling bonds (unbonded bonds) of δ- polarized N atoms are arranged, thereby making the upper surface of the light-emitting element 13 and the terminal functional groups -CF ３ The BVE has good adhesion (chemical bonding) or affinity to amorphous fluororesin obtained by cyclization polymerization.
[0049] Furthermore, since dangling bonds of N atoms exist on the side surfaces of the element substrate 26 (for example, the a-face and m-face), the side surfaces of the element substrate 26 and the terminal functional groups are -CF ３ It exhibits good adhesion (chemical bonding) or affinity to amorphous fluororesins obtained by cyclization polymerization of BVE.
[0050] Furthermore, in the light-emitting device 100 of this embodiment, since dangling bonds of N atoms also exist on the surface of the AlN polycrystalline ceramic material of the substrate 17 of the device substrate 11, the surface of the device substrate 11 and the terminal functional groups are -CF ３ It exhibits good adhesion (chemical bonding) or affinity with amorphous fluororesins obtained by cyclization polymerization of BVE.
[0051] In this embodiment, the light-emitting device 100 does not necessarily have an annular member 21 formed on the upper surface of the substrate 17, and the first sealing member 15A may cover the upper surface of the substrate 17 and the surface of the light-emitting element 13.
[0052] [Manufacturing Method for Light-Emitting Device 100] The manufacturing method for the light-emitting device 100 will be described below with reference to Figures 4 to 11. Each of Figures 4 to 11 is a cross-sectional view showing an example of the manufacturing process for the light-emitting device 100.
[0053] The light-emitting device 100 is manufactured by a procedure that includes a device substrate preparation step of preparing a device substrate 11, an element bonding step of bonding a light-emitting element 13 to the device substrate 11, a first sealing member formation step of forming a first sealing member 15A on the device substrate 11, and a second sealing member formation step of forming a second sealing member 15B on the first sealing member 15A.
[0054] [Device Substrate Preparation Process] First, as shown in Figure 4, a device substrate 11 is prepared, on which element mounting electrodes 18, annular members 21, mounting electrodes 23, and conductive vias 24 are formed on a base material 17. Note that there are as many device substrates 11 as there are light-emitting devices 100 to be manufactured at one time, but only one of them is shown in Figure 4.
[0055] In the manufacturing of the device substrate 11, each of the element mounting electrode 18, annular member 21, mounting electrode 23, and conductive via 24 is formed by sequentially patterning various metals on the upper and lower surfaces of the substrate 17 using a film deposition method such as sputtering, electroless plating, or electrolytic plating.
[0056] In the light-emitting device 100 of this embodiment, the size and thickness of the base material 17 of the device substrate 11 are set to 3.6 mm square on each side and 0.5 mm thick. In addition, in the light-emitting device 100 of this embodiment, the inner diameter of the annular member 21 is set to 2.7 mm.
[0057] [Element Bonding Process] Next, as shown in Figure 5, the light-emitting element 13 is bonded to the upper surface of the device substrate 11. In the light-emitting device 100 of this embodiment, the size and thickness of the light-emitting element 13 are set to 0.95 mm on the long side, 0.75 mm on the short side, and 0.11 mm in thickness.
[0058] Specifically, first, a solder paste containing 22 wt% fine particles of Au-Sn, which will become a bonding member 31 after heating, is applied to the surface of the element mounting electrode 18 of the device substrate 11 by screen printing or potting. Next, the light-emitting element 13 is placed on the element mounting electrode 18 to which the solder paste has been applied, such that the p electrode 28 and n electrode 29 overlap.
[0059] Subsequently, the solder paste is heated to 300°C in a reflow oven to melt and solidify the 20 wt% Au-Sn fine particles contained in the solder paste, causing the paste components other than Au-Sn to volatilize, and the light-emitting element 13 is bonded to the device substrate 11 via the bonding member 31. This process forms a mounting substrate with the light-emitting element bonded. For bonding the light-emitting element 13, bump bonding, thermocompression bonding, etc., can be selected.
[0060] [First sealing member formation process] Next, a first sealing member 15A is formed within the sealing body 15, covering the upper surface of the base material 17, the element mounting electrode 18, the annular member 21, and the light-emitting element 13.
[0061] First, as shown in Figure 6, an amorphous fluororesin solution AC (hereinafter referred to as resin solution AC), which is an amorphous fluororesin that will become the first sealing member 15A, is applied to the entire upper surface of the device substrate 11 using, for example, a spray nozzle SN.
[0062] Subsequently, the apparatus substrate 11, onto which the resin solution AC has been dropped, is placed on a hot plate, and the underside of the apparatus substrate 11 is heated at 230°C for 60 minutes to evaporate the solvent in the resin solution AC and dry it (volatilization step).
[0063] After the solvent in the resin solution AC is evaporated, heating is continued at 230°C for 60 minutes (additional heat treatment step). This causes the dried fluororesin to soften and spread continuously, wetting and coating the surface of the light-emitting element 13 to the edge of the upper surface of the substrate 17. In this way, the adhesion of the first sealing member 15A to the device substrate 11 and the light-emitting element 13 is improved.
[0064] As a result of these operations, a first sealing member 15A, which is a thin film of amorphous fluororesin, is formed on the upper surface of the device substrate 11, extending over the surface of the light-emitting element 13 and the upper surface of the substrate 17, as shown in Figure 7.
[0065] [Second sealing member formation process] Next, a second sealing member 15B is formed to cover the first sealing member 15A of the sealing body 15. As described above, the second sealing member 15B is formed by compression molding using a pair of molds consisting of a first mold M1 and a second mold M2.
[0066] The first mold M1 has a flat plate shape and functions as a holding mold that holds the object to be formed as a resin body in compression molding and applies pressure to the second mold M2 while holding the object.
[0067] The second mold M2 has a bullet-shaped recess CA that is convex downwards, and functions as a mold that molds a resin body into a desired shape while receiving pressure from the first mold M1 during compression molding.
[0068] First, as shown in Figure 8, the device substrate 100A with the first sealing member 15A formed on it is fixed to the first mold M1 in such a manner that the upper surface of the device substrate 11, i.e., the surface on which the light-emitting element 13 is formed, faces downward in the figure.
[0069] Furthermore, as shown in Figure 8, one amorphous fluororesin pellet RP (hereinafter referred to as resin pellet RP), which will serve as the second sealing member 15B, is placed on the peripheral edge of the recess CA of the second mold M2. In other words, the resin pellet RP is placed so as to cover the recess CA of the second mold M2. The resin pellet RP used in the manufacture of this light-emitting device 100 is a rectangular prism shape with a top and bottom surface that has sides of 1.8 mm and a height of 1.7 mm.
[0070] Furthermore, the shape of the resin pellet RP that becomes the second sealing member 15B is not limited to a rectangular prism, but can also be a polygonal prism such as a hexagonal prism or octagonal prism, a cylinder, or a concentric polygonal prism or cylinder. In short, the resin pellet RP has a shape on its surface that contacts the upper surface of the light-emitting element 13, and it is sufficient that it can be held by the second mold M2 to the extent that it does not wobble when it contacts the upper surface of the light-emitting element 13.
[0071] For example, the resin pellet RP may be in the form of a pyramidal or conical shape with a bottom surface that contacts the upper surface of the light-emitting element 13, or the resin pellet RP may be held in the second mold M2 in such a manner that its side surface and the edge of the recess CA are in contact. In short, the resin pellet RP only needs to have a shape such that its bottom surface (upper side in Figure 8) can enclose the upper and side surfaces of the light-emitting element 13.
[0072] Next, the first mold M1 and the second mold M2 are heated to 180°C each under atmospheric conditions. As a result, heat is transferred from the first mold M1 and the second mold M2 to the first sealing member 15A and the resin pellet RP, respectively, causing the first sealing member 15A and the resin pellet RP to soften. The method of heating and softening the resin is not limited to changing the ambient temperature or directly heating the first sealing member 15A and the resin pellet RP with a radiant heater.
[0073] Next, as shown in Figure 9, while continuing to heat at 180°C, the first mold M1 is lowered as indicated by the arrow in the figure, and the light-emitting element bonded device substrate 100A on which the first sealing member 15A is formed is pressed against the softened resin pellet RP. In this embodiment, the load applied during pressing is 40 kgf.
[0074] This operation causes the softened resin pellet RP to deform within the recess CA due to pressure from the device substrate 100A with the light-emitting element bonded to it, embedding the resin pellet RP so as to enclose the light-emitting element 13. At this time, the softened resin pellet RP is molded to a shape that conforms to the recess CA of the second mold M2. In other words, the resin pellet RP is molded into a bullet-shaped resin body that covers the light-emitting element 13.
[0075] In this way, by placing the resin pellets RP in each of the recesses of the second mold M2, in the initial stages of the descent of the first mold M1, the bottom surface of the resin pellets RP encloses the top surface, sides, and substrate surface of the bonding base of the light-emitting element 13, while first adhering to them. Then, as the descent of the first mold M1 progresses, the resin pellets RP deform, and the adhesion progresses from the areas that have been enclosed to the periphery of the device substrate 11. In other words, a sealant 15 with excellent adhesion to the light-emitting element 13 and the device substrate 11 can be formed.
[0076] Furthermore, during the process in which the resin pellets RP soften and flow to cover the first sealing member 15A, a weldable adhesive surface is formed with the first sealing member 15A. In other words, the softened resin pellets RP adhere well (bond) to the first sealing member 15A.
[0077] Furthermore, because the softened resin pellets RP adhere well to the first sealing member 15A, air bubbles are less likely to remain at the interface between the first sealing member 15A and the second sealing member 15B after the sealing body 15 is formed. As a result, the light-emitting element 13 and the entire sealing body 15 can be firmly adhered together while suppressing air bubbles within the sealing body 15, and especially in the region close to the interface between the sealing body 15 and the light-emitting element 13.
[0078] Furthermore, by providing the annular member 21 on the upper surface of the base material 17, the outflow of softened resin pellets RP can be suppressed (the internal pressure of the annular member 21 can be increased), thereby improving the adhesion (bonding) between the resin pellets RP and the inside of the annular member 21.
[0079] When the gap including the recess CA between the first mold M1 and the second mold M2 is filled with resin pellets RP, the descent of the first mold M1 stops, resulting in the configuration shown in Figure 10. Holding it in this state for 5 to 10 minutes improves the adhesion between the first sealing member 15A and the second sealing member 15B.
[0080] Finally, as shown in Figure 11, the temperatures of the first mold M1 and the second mold M2 are cooled to a temperature below the softening point of the amorphous fluororesin, for example, to about 50-80°C, and the temperature of the first mold M1 is raised as indicated by the arrow in the figure.
[0081] This operation causes the second sealing member 15B to be removed from the second mold M2 while remaining in close contact with the first sealing member 15A. As a result, a device substrate 100A with the first sealing member 15A and the second sealing member 15B bonded to it is obtained.
[0082] Furthermore, if, for example, multiple resin pellets RP are placed in the recess CA of the second mold M2, air is more likely to be trapped between the first sealing member 15A and the second sealing member 15B, which may result in the formation of air bubbles at the interface between the first sealing member 15A and the second sealing member 15B after the light-emitting device 100 is manufactured. Therefore, in order to prevent the formation of such air bubbles, it is preferable that only one resin pellet RP is placed in the second mold M2.
[0083] [Individualization Process] As the final step, the device substrate 11, which consists of the same number of light-emitting devices 100 to be manufactured at one time, is divided into individual pieces using a dicer so that each piece becomes a light-emitting device 100 having a single light-emitting element 13. This allows the light-emitting device 100 to be manufactured. The annular member 21 prevents the cutting stress of the dicer from propagating to the inside of the annular member 21 during individualization. Therefore, a highly reliable light-emitting device can be manufactured in which the sealant 15 does not peel off.
[0084] In this embodiment, the amorphous fluororesin, which is the material of the sealant 15 constituting the light-emitting device 100, has excellent light resistance (e.g., resistance to yellowing) and light transmittance to ultraviolet light in the wavelength range of 220 nm to 300 nm, but on the other hand, it has the characteristic of having low adhesion (chemical bonding) or affinity to other substances.
[0085] Therefore, even if one attempts to form a second sealing member 15B to cover the first sealing member 15A after it has been formed, because there is almost no tackiness between the surfaces of the first sealing member 15A and the resin pellets RP, the resin pellets RP may move significantly when brought into contact with the surface of the first sealing member 15A during the formation of the second sealing member 15B. This can result in the second sealing member 15B not being properly molded or poor adhesion between the second sealing member 15B and the first sealing member 15A.
[0086] When this occurs, the center of the second sealing member 15B and the light-emitting center of the light-emitting element 13 become misaligned in a plan view of the light-emitting device 100 from above, which may reduce the output of light emitted from the light-emitting device 100. Furthermore, in addition to the molding defect of the second sealing member 15B, the aforementioned poor adhesion may cause a sealing defect of the light-emitting element 13. In other words, the reliability of the light-emitting device may decrease.
[0087] Therefore, in the manufacturing of the light-emitting device 100 of this embodiment, as described above, after the formation of the first sealing member 15A, the second sealing member 15B is formed by compression molding using a mold with preheating and press-fitting.
[0088] In this invention, by forming the second sealing member 15B using a method that involves preheating before molding, molding defects of the second sealing member 15B are prevented, and the adhesion of the second sealing member 15B to the first sealing member 15A is improved. This improves the reliability of the light-emitting device.
[0089] Furthermore, according to the manufacturing method of the light-emitting device 100 of this embodiment, since multiple second sealing members 15B can be formed at once, the manufacturing time can be shortened compared to, for example, the case in which precursor resins that will become second sealing members 15B are placed one by one on the first sealing member 15A to form the second sealing members 15B.
[0090] In the manufacturing method of the light-emitting device 100 of this embodiment, for example, as shown in Figure 12, an air injection hole H may be provided in the second mold M2 at the periphery of the recess CA. This allows gas to be released from the recess CA through the air injection hole H. By adjusting the pressure of this gas release, the pressure inside the recess CA when the first sealing member 15A and the second sealing member 15B are in close contact can be controlled.
[0091] Furthermore, by introducing air through the air injection holes H after the formation of the second sealing member 15B, the second sealing member 15B can be easily removed from the second mold M2. The configuration of the air injection holes H is not limited to this, and for example, multiple air injection holes H may be provided in the second mold M2.
[0092] The light-emitting device 100 described in the above-mentioned embodiment can be used as a light source for various devices. For example, the light-emitting device 100 can be used as a light source for a resin curing device, a light source for a sterilization / disinfection / sterilization device, or a sensor light source for a distance measuring device.
[0093] 100 Light-emitting device 11 Device substrate 13 Light-emitting element 15 Sealing member 15A First sealing member 15B Second sealing member 18 Element mounting electrode 21 Annular member 23 Mounting electrode
Claims
1. An element bonding step to form an element-bonded mounting substrate by bonding a light-emitting element that emits ultraviolet light to a pair of mounting electrodes of a device substrate having a flat substrate and a pair of mounting electrodes formed on the upper surface of the substrate; and a sealing body forming step to form a translucent sealing body made of amorphous fluororesin that seals the light-emitting element on the device substrate, wherein the sealing body forming step comprises: a first step of forming a resin layer made of amorphous fluororesin over the upper surface of the device substrate and the surface of the light-emitting element; and a second step after the first step of holding the element-bonded mounting substrate in a holding mold so that its bottom surface is in contact with the holding mold, arranging amorphous fluororesin pellets on the periphery of the recess of a molding die having a recess, softening the resin layer and the amorphous fluororesin pellets by heating, and closing the holding mold and the molding die to press the element-bonded mounting substrate against the amorphous fluororesin pellets, deforming the amorphous fluororesin pellets to cover the resin layer and form the sealing body. A method for manufacturing a light-emitting device, characterized by including the following:
2. The method for manufacturing a light-emitting device according to claim 1, characterized in that the first step includes a volatilization step of applying a solution obtained by dissolving amorphous fluororesin in a solvent over the upper surface of the device substrate and the surface of the light-emitting element, and volatilizing the solvent of the applied solution by heat treatment.
3. The method for manufacturing a light-emitting device according to claim 2, characterized in that the first step includes an additional heat treatment step of subsequently performing heat treatment after the volatilization step.
4. The method for manufacturing a light-emitting device according to any one of claims 1 to 3, characterized in that the recess of the mold has a bullet shape.
5. The terminal functional group of the amorphous fluororesin constituting the sealant is -CF ３ A method for manufacturing a light-emitting device according to any one of claims 1 to 3, characterized in that it is such.
6. The method for manufacturing a light-emitting device according to any one of claims 1 to 3, characterized in that the light-emitting element emits ultraviolet light with a wavelength of 200 nm to 300 nm.