Manufacturing method of light-emitting device

Abstract

To provide a manufacturing method of a light-emitting device capable of improving the bondability of a light emitting element and a wiring board.SOLUTION: A manufacturing method of a light-emitting device comprises the steps of: preparing a plurality of light-emitting elements including a semiconductor structure, an electrode to be arranged on a lower surface of the semiconductor structure, and a conductive member provided on the lower surface of the electrode; arranging the plurality of light-emitting elements above a wiring board having a base material and a plurality of wiring parts to be provided on an upper surface side of the base material, via a holding member, and arranging the plurality of light-emitting elements so that the conductive member provided in each of the plurality of light-emitting elements faces each wiring part across a gap; removing the holding member by an ozon gas in a temperature environment that is lower than a fusion point of the conductive member, and bringing the conductive member into contact with the wiring part; and heating the conductive member to the temperature that is higher than the fusion point of the conductive member to bond the electrode and each wiring part.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] The present disclosure relates to a method for manufacturing a light-emitting device.

Background Art

[0002] Patent Document 1 discloses a method for manufacturing an electronic device, which includes a step of exposing the upper surface of a first electrode of a first electronic component to an organic acid, a step of irradiating ultraviolet rays onto the upper surface of the first electrode exposed to the organic acid, and a step of pressing and bonding the first electrode and a second electrode of a second electronic component to each other while heating.

Prior Art Document

Patent Document

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In a light-emitting device, it is required to improve the bonding property between a light-emitting element and a wiring substrate.

[0005] An object of the present disclosure is to provide a method for manufacturing a light-emitting device that improves the bonding property between a light-emitting element and a wiring substrate.

Means for Solving the Problems

[0006] A method for manufacturing a light-emitting device according to an embodiment of the present disclosure includes a step of preparing a plurality of light-emitting elements including a semiconductor structure, an electrode disposed on a lower surface of the semiconductor structure, and a conductive member provided on a lower surface of the electrode; a step of disposing the plurality of light-emitting elements via a holding member above a wiring substrate including a base material and a plurality of wiring portions provided on an upper surface side of the base material, the disposing step including disposing the plurality of light-emitting elements such that the conductive member included in each of the plurality of light-emitting elements faces each of the wiring portions with a gap therebetween; a step of removing the holding member with ozone gas in a temperature environment lower than the melting point of the conductive member and bringing the conductive member into contact with the wiring portion; and a step of heating the conductive member to a temperature equal to or higher than the melting point of the conductive member to bond the electrode and the wiring portion.

[0007] A method for manufacturing a light-emitting device according to an embodiment of the present disclosure includes a step of preparing a plurality of light-emitting elements including a semiconductor structure and an electrode disposed on a lower surface of the semiconductor structure; a step of disposing the plurality of light-emitting elements via a holding member above a wiring substrate including a base material, a plurality of wiring portions provided on an upper surface side of the base material, and a conductive member provided on an upper surface of the wiring portion, the disposing step including disposing the plurality of light-emitting elements such that the conductive member included in the wiring substrate faces the electrode of each of the light-emitting elements with a gap therebetween; a step of removing the holding member with ozone gas in a temperature environment lower than the melting point of the conductive member and bringing the conductive member into contact with the electrode; and a step of heating the conductive member to a temperature equal to or higher than the melting point of the conductive member to bond the electrode and the wiring portion.

Advantages of the Invention

[0008] According to an embodiment of the present disclosure, it is possible to provide a method for manufacturing a light-emitting device that improves the bonding property between a light-emitting element and a wiring substrate.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Embodiments for Carrying Out the Invention

[0010] Hereinafter, with reference to the drawings, a method for manufacturing a light-emitting device according to an embodiment of the present disclosure will be described in detail. However, the following embodiments illustrate a method for manufacturing a light-emitting device for embodying the technical idea of the embodiments, and are not limited thereto. In addition, the dimensions, materials, shapes, relative arrangements, etc. of the constituent members described in the embodiments are not intended to limit the scope of the present disclosure only thereto without specific description, but are merely illustrative examples. Note that the sizes, positional relationships, etc. of the members shown in each drawing may be exaggerated for clarity of explanation. In the following description, the same names and reference numerals indicate the same or similar members, and detailed descriptions thereof will be omitted as appropriate. In some cases, an end view showing only the cut surface is used as a cross-sectional view.

[0011] In the figures shown below, the directions may be indicated by the X-axis, Y-axis, and Z-axis. The X-axis, Y-axis, and Z-axis are directions perpendicular to each other. The direction in which the arrow points in the X-axis direction is denoted as the +X direction, and the opposite direction of the +X direction is denoted as the -X direction. The direction in which the arrow points in the Y-axis direction is denoted as the +Y direction, and the opposite direction of the +Y direction is denoted as the -Y direction. The direction in which the arrow points in the Z-axis direction is denoted as the +Z direction, and the opposite direction of the +Z direction is denoted as the -Z direction. In addition, in the terms of the embodiments, the top view means viewing the object from the +Z direction. However, these do not limit the orientation of the light-emitting device during use, and the orientation of the light-emitting device is arbitrary. In the embodiments, the surface of the object when viewed from the +Z direction is defined as the "upper surface", and the surface of the object when viewed from the -Z direction is defined as the "lower surface". In the following embodiments, along the X-axis, Y-axis, and Z-axis means that the object has an inclination within a range of ±10° with respect to these axes. In the embodiments, perpendicularity may include an error within ±10° with respect to 90°.

[0012] In the present disclosure, unless otherwise specified, polygons such as rectangles include those with rounded corners, chamfers, bevels, or rounds at the corners of the polygon, and are also referred to as polygons. In addition, not limited to the corners (ends of the sides), shapes with processing on the middle part of the sides are also referred to as polygons. That is, shapes with partial processing while leaving the polygon as a base are included in the interpretation of "polygon" described in the present disclosure.

[0013] In addition, not limited to polygons, the same applies to terms representing specific shapes such as trapezoids, circles, and unevenness. The same also applies to terms related to each side forming the shape. That is, even if a side has processing at the corner or the middle part, the processed part is included in the interpretation of "side".

[0014] [Embodiment] <Overall Configuration of Light-Emitting Device 1> As a premise for explaining the manufacturing method of the light-emitting device 1 according to the embodiment, an example of the overall configuration of the light-emitting device 1 will be described with reference to FIGS. 1 and 2. FIG. 1 is a schematic perspective view of the light-emitting device 1 according to the embodiment. FIG. 2 is a schematic cross-sectional view of the light-emitting device 1 according to the embodiment, cut along the line II-II shown in FIG. 1.

[0015] As shown in FIG. 2, the light-emitting device 1 includes a plurality of light-emitting elements 10 and a wiring substrate 20. The light-emitting device 1 may further include other components such as a wavelength conversion member 40, a light-shielding member 50, a wire-shaped conductor thin wire 60, a package substrate 70, and a coating member 80. The wavelength conversion member 40 is disposed above the light-emitting element 10 and converts the wavelength of the light emitted by the light-emitting element 10. The light-shielding member 50 covers the side surface of the light-emitting element 10.

[0016] In the example shown in FIG. 2, two light-emitting elements 10 arranged in the X-axis direction are shown as the plurality of light-emitting elements 10. However, the number of light-emitting elements 10 included in the light-emitting device 1 is not limited to two. The number of light-emitting elements 10 may be three or more.

[0017] The lower surface of the wiring substrate 20 may be joined to the upper surface of the package substrate 70 via, for example, a joining member 90 made of a metallic material. Also, the first terminal 25 provided on the upper surface of the wiring substrate 20 is electrically connected to the second terminal 75 provided on the upper surface of the package substrate 70 via the conductive fine wire 60. The second terminal 75 of the package substrate 70 is electrically connected to an external power source. That is, the first terminal 25 provided on the upper surface of the wiring substrate 20 is electrically connected to the external power source via the second terminal 75 of the package substrate 70 and the conductive fine wire 60. The conductive fine wire 60 is covered by a covering member 80.

[0018] <Light-emitting element 10> Each of the plurality of light-emitting elements 10 is, for example, a semiconductor light-emitting element such as an LED (Light Emitting Diode) or an LD (Laser Diode). As shown in FIG. 2, each of the plurality of light-emitting elements 10 has a semiconductor structure 11 and an electrode 12. Specifically, a pair of electrodes 12 are respectively provided on the lower surface of each semiconductor structure 11. Here, one of the pair of electrodes 12 is an example of the "first electrode". The other of the pair of electrodes 12 is an example of the "second electrode". The number of electrodes 12 is not limited to a pair in which there is one positive electrode and one negative electrode, and there may be a plurality of each electrode, such as two positive electrodes and two negative electrodes.

[0019] Each of the plurality of light-emitting elements 10 preferably further has a plurality of conductive members 13. The plurality of conductive members 13 are respectively provided on the lower surfaces of the pair of electrodes 12 included in each light-emitting element 10. However, as in the modified example described separately with reference to FIGS. 8 and 9, in a state before the light-emitting element 10 and the wiring substrate 20 are joined, the conductive member 13 may be provided on the upper surface of the wiring portion 22 of the wiring substrate 20 instead of the lower surface of the electrode 12.

[0020] The semiconductor structure 11 emits, for example, blue light. The semiconductor structure 11 includes an n-type semiconductor layer, an active layer, and a p-type semiconductor layer that are sequentially stacked in the Z-axis direction. Each of the n-type semiconductor layer, the active layer, and the p-type semiconductor layer in the semiconductor structure 11 is, for example, In X AlY Ga 1-X-Y It is composed of a nitride semiconductor such as N(0≦X, 0≦Y, X + Y≦1). The upper surface of the semiconductor structure 11 corresponds to the light extraction surface.

[0021] The semiconductor structure 11 has an upper surface, a lower surface, and one or more side surfaces connecting the outer edges of the upper and lower surfaces. Also, the semiconductor structure 11 has a substantially rectangular outer shape in a top view. However, the semiconductor structure 11 may have other outer shapes such as substantially circular, substantially elliptical, or substantially polygonal in a top view.

[0022] The electrode 12 includes, for example, metal materials such as gold (Au), silver (Ag), tin (Sn), aluminum (Al), platinum (Pt), copper (Cu), ruthenium (Ru), and rhodium (Rh). However, the material constituting the electrode 12 is not limited to these. Also, the electrode 12 may have a single-layer structure composed of a single metal layer, or may have a laminated structure in which a plurality of metal layers are stacked. When using, for example, metal materials such as Au, Ag, Sn, Al, Pt, Cu, Ru, and Rh as the conductive member 13, eutectic materials such as gold-tin (AuSn), lead-bismuth (PbBi), and indium-tin (InSn) may be used as the electrode 12.

[0023] The conductive member 13 may be composed of a single metal material, or may be composed of a eutectic material containing a plurality of metal materials such as an alloy. Examples of the material constituting the conductive member 13 include AuSn, PbBi, and InSn. However, the material constituting the conductive member 13 is not limited to these. When using, for example, eutectic materials such as AuSn, PbBi, and InSn as the electrode 12, metal materials such as Au, Ag, Sn, Al, Pt, Cu, Ru, and Rh may be used as the conductive member 13.

[0024] <Wiring substrate 20> The wiring board 20 has a substantially rectangular outer shape in a top view. However, the wiring board 20 may have other outer shapes such as a substantially circular shape, a substantially elliptical shape, or a substantially polygonal shape in a top view. The wiring board 20 may include an integrated circuit for controlling the light emission operations of the plurality of light emitting elements 10. Examples of the integrated circuit include electronic circuits such as an ASIC (Application Specific Integrated Circuit).

[0025] As shown in FIG. 2, the wiring board 20 has a base material 21 and a plurality of wiring portions 22 provided on the upper surface side of the base material 21. In a state before the light emitting element 10 and the wiring board 20 are joined, a conductive member 13 may be provided on the upper surface of each of the plurality of wiring portions 22.

[0026] At least the upper surface of each wiring portion 22 is exposed outside the base material 21 and is joined to the electrode 12 via the conductive member 13. Further, the wiring board 20 may further include other wiring portions other than the wiring portions 22, such as lower surface wirings provided on the lower surface side of the base material 21 and inner layer wirings penetrating the base material 21 in the Z-axis direction.

[0027] The base material 21 is the base material of the wiring board 20. As shown in FIG. 2, the base material 21 has an upper surface, a lower surface, and side surfaces connecting the outer edges of the upper surface and the lower surface. Examples of the material constituting the base material 21 include semiconductor substrates such as silicon, ceramic substrates such as aluminum nitride, and resin substrates such as glass epoxy. However, the material constituting the base material 21 is not limited to these.

[0028] Other examples of the material constituting the wiring portion 22 include Au, Ag, Al, nickel (Ni), Rh, titanium (Ti), Pt, palladium (Pd), molybdenum (Mo), chromium (Cr), and tungsten (W). However, the material constituting the wiring portion 22 is not limited to these.

[0029] The wiring portion 22 is electrically connected to the first terminal 25, for example, via the inner layer wiring of the base material 21. Thereby, the wiring portion 22 is connected to an external power supply via the first terminal 25. Further, the semiconductor structure 11 is connected to an external power supply via the first terminal 25, the wiring portion 22, the conductive member 13, and the electrode 12.

[0030] <Method for manufacturing the light-emitting device 1> Next, with reference to FIGS. 3 to 7, a method for manufacturing the light-emitting device 1 according to the embodiment will be described. The method for manufacturing the light-emitting device 1 according to the embodiment includes a step of preparing a plurality of light-emitting elements 10, a step of arranging the plurality of light-emitting elements 10 above the wiring substrate 20, a step of bringing the conductive member 13 into contact with the wiring portion 22, and a step of joining the electrode 12 and the wiring portion 22. Note that the step of bringing the conductive member 13 into contact with the wiring portion 22 may be referred to as "the step of bringing the conductive member 13 into contact". Hereinafter, each step will be described in detail.

[0031] <Step of preparing a plurality of light-emitting elements 10> First, the step of preparing a plurality of light-emitting elements 10 is performed. With reference to FIG. 3, the step of preparing a plurality of light-emitting elements 10 will be described. FIG. 3 is a schematic cross-sectional view of a plurality of light-emitting elements 10 cut along the XZ plane. As shown in FIG. 3, a plurality of light-emitting elements 10 each including a semiconductor structure 11, an electrode 12, and a conductive member 13 are prepared. In the example shown in FIG. 3, two light-emitting elements 10a and 10b are prepared. However, the number of light-emitting elements 10 to be prepared may be three or more.

[0032] The manufacturing method of the prepared light-emitting elements 10a and 10b is, for example, as follows. First, an electrode 12 is formed on the lower surface of the semiconductor structure 11. Specifically, electrodes 12a1 and 12a2 are formed on the lower surface of the semiconductor structure 11a. Also, electrodes 12b1 and 12b2 are formed on the lower surface of the semiconductor structure 11b. Examples of the method for forming the electrode 12 include a sputtering method, a vacuum evaporation method, and a plating method. However, the method for forming the electrode 12 is not limited thereto.

[0033] Subsequently, conductive members 13 are respectively formed on the lower surfaces of the electrodes 12. Specifically, a conductive member 13a1 is formed on the lower surface of the electrode 12a1, a conductive member 13a2 is formed on the lower surface of the electrode 12a2, a conductive member 13b1 is formed on the lower surface of the electrode 12b1, and a conductive member 13b2 is formed on the lower surface of the electrode 12b2. Examples of the method for forming the conductive member 13 include a sputtering method, a vacuum evaporation method, and a plating method. However, the method for forming the conductive member 13 is not limited to these. Through these steps, the light-emitting elements 10a and 10b are respectively fabricated.

[0034] Here, even if the thicknesses of the pair of electrodes 12 disposed on the lower surface of the semiconductor structure 11 are the same, depending on the difference between the height position (position in the Z-axis direction) of the p-type semiconductor layer and the height position of the n-type semiconductor layer in the semiconductor structure 11, the height position of the lower surface of one electrode 12 and the height position of the lower surface of the other electrode 12 may be different. Accordingly, even if the thicknesses of the conductive member 13 formed on the lower surface of one electrode 12 and the conductive member 13 formed on the lower surface of the other electrode 12 are the same, the height positions of the lower surfaces of the respective conductive members 13 may be different.

[0035] Therefore, it is preferable to grind the lower surfaces of the conductive members 13 respectively formed on the lower surfaces of the electrodes 12. By grinding the lower surfaces of the respective conductive members 13, the lower surfaces of the different conductive members 13 can be flattened. Also, the height positions of the lower surfaces of the different conductive members 13 can be aligned. As a result, when finally joining the light-emitting element 10 and the wiring substrate 20, the joinability between the conductive member 13 and the wiring portion 22 can be improved. Examples of the method for grinding the lower surface of the conductive member 13 include a polishing method and a grinding method. However, the method for grinding the lower surface of the conductive member 13 is not limited to these.

[0036] <Step of disposing a plurality of light-emitting elements 10 above the wiring substrate 20> Subsequently, a step of arranging a plurality of light-emitting elements 10 above the wiring substrate 20 is performed. With reference to FIG. 4, the step of arranging a plurality of light-emitting elements 10 above the wiring substrate 20 will be described. FIG. 4 is a schematic cross-sectional view taken along the XZ plane of the wiring substrate 20 and a plurality of light-emitting elements 10 arranged above the wiring substrate 20.

[0037] First, the prepared light-emitting elements 10a and 10b are fixed to the lower surface of the carrier glass 200. As shown in FIG. 4, the carrier glass 200 includes a plate-shaped glass base 210 and, for example, a resin layer 220 provided on the lower surface of the glass base 210. The lower surface of the resin layer 220 corresponds to the lower surface of the carrier glass 200. The resin layer 220 has adhesiveness. Thereby, each of the light-emitting elements 10a and 10b is fixed to the lower surface of the carrier glass 200 via the resin layer 220.

[0038] In the example shown in FIG. 4, the light-emitting elements 10a and 10b are arranged along the X-axis direction on the lower surface of the carrier glass 200. In addition to the light-emitting elements 10a and 10b, when other light-emitting elements 10 are fixed to the carrier glass 200, each of the plurality of light-emitting elements 10 including the light-emitting elements 10a and 10b may be arranged, for example, in a matrix along the X-axis direction and the Y-axis direction. However, the direction in which the plurality of light-emitting elements 10 are arranged is not limited to these.

[0039] Subsequently, the carrier glass 200 and the light-emitting elements 10a and 10b fixed to the lower surface of the carrier glass 200 are transported above the wiring substrate 20 by any transport means. As shown in FIG. 4, the wiring substrate 20 includes a base material 21 and a plurality of wiring portions 22 provided on the upper surface side of the base material 21. In addition, a plurality of holding members 28 extending in the Z-axis direction from the upper surface of the base material 21 are provided. The plurality of holding members 28 respectively hold the light-emitting elements 10a and 10b. Each of the light-emitting elements 10a and 10b is arranged above the wiring substrate 20 via the holding member 28.

[0040] As an example of the holding member 28, an organic substance such as resin can be mentioned. Further, as a method for forming the holding member 28, a photolithography method can be mentioned. However, the method for forming the holding member 28 is not limited to this.

[0041] When the light-emitting elements 10a and 10b are arranged above the wiring substrate 20, the conductive members 13 provided in each of the light-emitting elements 10a and 10b face the respective wiring portions 22 with a gap therebetween. Specifically, as shown in FIG. 4, the conductive member 13a1 faces the wiring portion 22a1 with a gap therebetween. The conductive member 13a2 faces the wiring portion 22a2 with a gap therebetween. The conductive member 13b1 faces the wiring portion 22b1 with a gap therebetween. The conductive member 13b2 faces the wiring portion 22b2 with a gap therebetween.

[0042] <Step of bringing the conductive member 13 into contact with the wiring portion 22> Next, a step of bringing the conductive member 13 into contact with the wiring portion 22 is performed. With reference to FIGS. 5 and 6, the step of bringing the conductive member 13 into contact with the wiring portion 22 will be described. FIG. 5 is a schematic cross-sectional view of a plurality of light-emitting elements 10 and a wiring substrate 20 cut along the XZ plane before the conductive member 13 and the wiring portion 22 come into contact with each other. FIG. 6 is a schematic cross-sectional view of a plurality of light-emitting elements 10 and a wiring substrate 20 cut along the XZ plane after the conductive member 13 and the wiring portion 22 come into contact with each other.

[0043] Here, prior to the step of bringing the conductive member 13 into contact with the wiring portion 22, the carrier glass 200 may be separated from the light-emitting elements 10a and 10b. In this case, after separating the carrier glass 200 from the light-emitting elements 10a and 10b, a weight member may be placed on the upper surfaces of the semiconductor structures 11a and 11b. On the other hand, without separating the carrier glass 200 from the light-emitting elements 10a and 10b, the step of bringing the conductive member 13 into contact with the wiring portion 22 may be performed in a state where the light-emitting elements 10a and 10b are fixed to the lower surface of the carrier glass 200. Hereinafter, the step of bringing the conductive member 13 into contact with the wiring portion 22 will be described in detail.

[0044] First, the light-emitting elements 10a and 10b held by the holding member 28 and the wiring board 20 are each conveyed into the chamber 710 of the heating device 700. As shown in FIG. 5, the heating device 700 includes a chamber 710 and a pipe 720 through which ozone gas flows. The chamber 710 includes a head 711 that supplies ozone gas into the space within the chamber 710, a first heater 712, a second heater 713, and an exhaust port 715. The head 711 is connected to one end of the pipe 720. The first heater 712 also functions as a stage on which the wiring board 20 is placed. The second heater 713 is provided at a position such as the side wall or the upper wall of the chamber 710 and warms the space within the chamber 710. The other end of the pipe 720 is connected to a cylinder or the like that stores ozone gas. Further, the pipe 720 preferably further includes a flow path switching means such as a valve that switches the supply and stop of ozone gas.

[0045] The heating device 700 preferably further includes a control unit that controls operations such as those of the first heater 712, the second heater 713, and the flow path switching means. As an example of the control unit, a computer that executes a predetermined control program can be mentioned. Further, the ozone gas within the chamber 710 is exhausted to the outside of the chamber 710 through the exhaust port 715. The heating device 700 preferably further includes a recovery mechanism that recovers the ozone gas exhausted from the chamber 710 through the exhaust port 715.

[0046] Subsequently, the inside of the chamber 710 that houses the light-emitting elements 10a and 10b, the wiring substrate 20, and the holding member 28 is depressurized using a pressure-reducing means such as a vacuum pump. The depressurization is preferably performed until the inside of the chamber 710 becomes a vacuum. After the inside of the chamber 710 is depressurized, the first heater 712 and the second heater 713 are driven to raise the temperature inside the chamber 710 to, for example, about 200°C. The temperature inside the chamber 710 is the temperature measured by a thermometer or the like provided inside the chamber 710. However, the temperature inside the chamber 710 after being heated by the first heater 712 and / or the second heater 713 is not limited to this. Note that the temperature inside the chamber 710 after being heated by the first heater 712 and / or the second heater 713 is below the melting point of the conductive member 13 so that the conductive member 13 does not melt.

[0047] Subsequently, ozone gas is supplied into the chamber 710 through the pipe 720. The ozone gas may be supplied continuously or intermittently. Also, as an example of the concentration of the ozone gas supplied into the chamber 710, a concentration in the range of 10 vol% to 15 vol% can be mentioned. However, the concentration of the ozone gas supplied into the chamber 710 is not limited to this. Note that "vol%" regarding the concentration of the ozone gas is the percentage of the volume of the ozone gas with respect to the total volume of the gas supplied into the chamber 710.

[0048] The ozone gas passes through the region inside the chamber 710 including the gap between the conductive member 13 and the wiring portion 22 facing each other. The ozone gas is decomposed into, for example, oxygen gas and atomic oxygen by the heat inside the chamber 710. Also, the atomic oxygen decomposed from the ozone gas decomposes the organic substances adhering to the lower surface of the conductive member 13 and the upper surface of the wiring portion 22. Thereby, each of the lower surface of the conductive member 13 and the upper surface of the wiring portion 22 can be cleaned. Hereinafter, including the atomic oxygen after decomposition, it is referred to as "ozone gas".

[0049] Ozone gas decomposes the holding member 28 containing resin. As a result, the holding member 28 is gradually decomposed, for example, from the upper surface side of the holding member 28. Also, as the holding member 28 is gradually decomposed, each of the light-emitting elements 10a and 10b moves in the -Z direction while maintaining a substantially horizontal posture due to its own weight. That is, the conductive member 13 and the wiring portion 22, which were separated from each other with a gap therebetween, approach each other.

[0050] Finally, the holding member 28 is removed by ozone gas. As a result, as shown in FIG. 6, the conductive member 13 and the wiring portion 22 facing each other come into contact. Specifically, the conductive member 13a1 contacts the wiring portion 22a1. The conductive member 13a2 contacts the wiring portion 22a2. The conductive member 13b1 contacts the wiring portion 22b1. The conductive member 13b2 contacts the wiring portion 22b2.

[0051] By the way, unlike the method described with reference to FIGS. 5 and 6, for example, when connecting the electrodes 12 of the light-emitting elements 10a and 10b held by the holding member 28 and the wiring portion 22 of the wiring substrate 20 using a plating method, the electrode 12 and the wiring portion 22 are separated by a distance corresponding to the thickness of the holding member 28. On the other hand, in the case of this embodiment, before removing the holding member 28, the conductive member 13 and the wiring portion 22, which were separated by the thickness of the holding member 28, are brought into contact with each other by removing the holding member 28 with ozone gas. As a result, both can be joined in a state where the distance between the electrode 12 and the wiring portion 22 is short. As a result, the joinability between the light-emitting element 10 and the wiring substrate 20 can be improved. Also, the yield of the light-emitting device 1 can be improved. Furthermore, since the distance between the electrode 12 and the wiring portion 22 is short, the electrical resistance of the conductor portion including the conductive member 13, the electrode 12, and the wiring portion 22 can be reduced. Also, the holding member 28 can be removed at the same timing as the step of cleaning the lower surface of the conductive member 13 and the upper surface of the wiring portion 22 with ozone gas. Therefore, it is not necessary to separately provide a step for removing the holding member 28, and the number of steps for manufacturing the light-emitting device 1 can be reduced.

[0052] Here, when a weight member is placed on the upper surface of the semiconductor structure 11, the conductive member 13 and the wiring portion 22 that are in contact with each other can be pressed by the weight member. That is, the conductive member 13 and the wiring portion 22 can be brought into contact with each other while applying a pressure in the -Z direction, for example, to each of them. It is preferable to use a mesh plate as the weight member. By using a mesh plate, while applying a load to the conductive member 13 and the wiring portion 22 facing each other, ozone gas can be uniformly circulated in the chamber 710 without being blocked by the mesh plate, and it becomes easy to remove the holding member 28.

[0053] Also, when performing the step of bringing the conductive member 13 into contact with the wiring portion 22 in a state where the light-emitting elements 10a and 10b are fixed to the lower surface of the carrier glass 200, the resin layer 220 of the carrier glass 200 can be removed by ozone gas. Thereby, even if a separate step of separating the carrier glass 200 from the light-emitting elements 10a and 10b is not performed, the carrier glass 200 can be separated from the light-emitting elements 10a and 10b in conjunction with the step of bringing the conductive member 13 into contact with the wiring portion 22. As a result, the number of steps in the manufacturing method of the light-emitting device 1 can be reduced, and the production efficiency of the light-emitting device 1 can be improved.

[0054] Also, even if not all of the resin layer 220 is removed by ozone gas, by removing a part of the resin layer 220, the contact area between the light-emitting elements 10a and 10b and the carrier glass 200 can be reduced. Thereby, when separating the carrier glass 200 from the light-emitting elements 10a and 10b in another step, the two can be easily separated without applying a strong force to pull the light-emitting elements 10a and 10b away from the carrier glass 200. As a result, it is possible to suppress some of the plurality of light-emitting elements 10 including the light-emitting elements 10a and 10b from not being removed from the lower surface of the carrier glass 200 and being separated from the wiring substrate 20 together with the transfer of the carrier glass 200. Further, when separating the carrier glass 200 from the light-emitting elements 10a and 10b, it is possible to suppress damage to the carrier glass 200 and the light-emitting elements 10a and 10b.

[0055] In the example shown in FIG. 6, the temperature in the chamber 710 is set to about 200° C., but for example, the temperature in the chamber 710 may be set to 150° C. or lower. At this time, it is preferable to supply ozone gas of 80 vol % or more into the chamber 710. More preferably, ozone gas of 90 vol % or more is supplied into the chamber 710, and even more preferably, ozone gas of 100 vol % is supplied.

[0056] By relatively lowering the temperature in the chamber 710, oxidation of the conductive member 13 can be suppressed. Thereby, the step of joining the electrode 12 and the wiring portion 22 can be performed without using flux. Further, as the temperature in the chamber 710 is relatively lowered, by relatively increasing the concentration of ozone gas supplied into the chamber 710, it is possible to suppress an excessive decrease in the cleaning function of the lower surface of the conductive member 13 and the upper surface of the wiring portion 22 by the ozone gas.

[0057] When the temperature in the chamber 710 is relatively lowered, instead of relatively increasing the concentration of ozone gas, oxidation of the conductive member 13 can be suppressed by adding an unsaturated hydrocarbon gas containing an alkene. Among the unsaturated hydrocarbon gases containing an alkene, it is preferable to add ethylene gas. By adding ethylene gas, the safety can be enhanced while reducing the manufacturing cost.

[0058] <Step of joining the electrode 12 and the wiring portion 22> Next, the step of joining the electrode 12 and the wiring portion 22 is performed. Referring to FIG. 7, the step of joining the electrode 12 and the wiring portion 22 will be described. FIG. 7 is a schematic cross-sectional view of a light-emitting element 10 and a wiring substrate 20 joined to each other through the electrode 12, the conductive member 13, and the wiring portion 22, cut along the XZ plane.

[0059] The step of joining the electrode 12 and the wiring portion 22 is preferably performed in the chamber 710 of the heating device 700 following the step of bringing the conductive member 13 into contact with the wiring portion 22. That is, after performing the step of bringing the conductive member 13 into contact with the wiring portion 22, it is preferable to perform the step of joining the electrode 12 and the wiring portion 22 with the plurality of light-emitting elements 10 and the wiring substrate 20 left in the chamber 710.

[0060] Thereby, the step of bringing the conductive member 13 into contact with the wiring portion 22 and the step of joining the electrode 12 and the wiring portion 22 can be performed successively using the same chamber 710. As a result, the production efficiency of the light-emitting device 1 can be increased. Also, between the step of bringing the conductive member 13 into contact with the wiring portion 22 and the step of joining the electrode 12 and the wiring portion 22, the light-emitting elements 10a, 10b and the wiring substrate 20 do not come into contact with the atmosphere. Thereby, it is possible to suppress the oxidation of the conductive member 13 and the adhesion of impurities. Hereinafter, the step of joining the electrode 12 and the wiring portion 22 will be described in detail.

[0061] First, the supply of ozone gas into the chamber 710 is stopped, and for example, the first heater 712 and / or the second heater 713 is driven to heat the conductive member 13 to a temperature equal to or higher than the melting point of the conductive member 13. For example, the temperature in the chamber 710 is raised from about 275°C to 300°C. Thereby, the conductive member 13 sandwiched between the electrode 12 and the wiring portion 22 melts. Thereafter, the first heater 712 and the second heater 713 are stopped, and the temperature in the chamber 710 is lowered to a temperature below the melting point of the conductive member 13. Thereby, the melted conductive member 13 solidifies and joins the electrode 12 and the wiring portion 22.

[0062] When the conductive member 13 is a eutectic material, the electrode 12 and the wiring portion 22 are eutectically joined via the conductive member 13. Thereby, the joinability between the electrode 12 and the wiring portion 22 can be further improved. The electrode 12 and the wiring portion 22 may be joined by liquid crystal diffusion bonding.

[0063] Further, when raising the temperature in the chamber 710 to melt the conductive member 13, a reducing gas containing formic acid may be supplied into the chamber 710. That is, in the step of joining the electrode 12 and the wiring portion 22, formic acid reflow may be performed. Thereby, oxidation of the conductive member 13 can be suppressed, and the electrode 12 and the wiring portion 22 can be joined without flux. Note that the reducing gas may be a gas containing only formic acid, or may be a gas other than formic acid.

[0064] Through these steps, the light-emitting device 1 according to the embodiment is obtained. However, the manufacturing method of the light-emitting device 1 may appropriately include other steps. The manufacturing method of the light-emitting device 1 may appropriately perform other steps such as, for example, a step of forming the wavelength conversion member 40 above the light-emitting element 10, a step of forming the light-shielding member 50 that covers the side surface of the light-emitting element 10, a step of arranging the conductor fine wire 60 that electrically connects the wiring substrate 20 and the package substrate 70, and a step of forming the covering member 80 that covers the conductor fine wire 60.

[0065] <Modification Example> Next, a method for manufacturing a light-emitting device according to a modification example of the embodiment will be described. The method for manufacturing a light-emitting device according to the modification example includes a step of preparing a plurality of light-emitting elements 10, a step of arranging the plurality of light-emitting elements 10 above the wiring substrate 20, a step of bringing the conductive member 13 into contact with the electrode 12, and a step of joining the electrode 12 and the wiring portion 22. Note that the step of bringing the conductive member 13 into contact with the electrode 12 may be referred to as "the step of bringing the conductive member 13 into contact".

[0066] Regarding the method for manufacturing a light-emitting device according to the modification example, differences from the method for manufacturing the light-emitting device 1 described above will be described with reference to FIGS. 8 to 11. FIG. 8 is a schematic cross-sectional view of a plurality of light-emitting elements 10 cut along the XZ plane. FIG. 9 is a schematic cross-sectional view of the wiring substrate 20 cut along the XZ plane. FIG. 10 is a schematic cross-sectional view of the wiring substrate 20 and a plurality of light-emitting elements 10 arranged above the wiring substrate 20 cut along the XZ plane. FIG. 11 is a schematic cross-sectional view of a plurality of light-emitting elements 10 and the wiring substrate 20 before the conductive member 13 and the wiring portion 22 come into contact with each other, cut along the XZ plane.

[0067] As shown in FIG. 8, in the step of preparing a plurality of light-emitting elements 10, for example, two light-emitting elements 10c and 10d are prepared. Here, each of the prepared light-emitting elements 10c and 10d includes an electrode 12 disposed on the lower surface of the semiconductor structure 11. On the other hand, in each of the light-emitting elements 10c and 10d, a conductive member 13 is not provided on the lower surface of the electrode 12. As shown in FIG. 9, the plurality of conductive members 13 are respectively formed on the upper surfaces of the plurality of wiring portions 22 provided in the wiring substrate 20. The step of forming the conductive member 13 on the upper surface of the wiring portion 22 may be performed before or after the step of preparing the plurality of light-emitting elements 10.

[0068] Next, in the step of disposing a plurality of light-emitting elements 10 above the wiring substrate 20, first, the light-emitting elements 10c and 10d are fixed to the lower surface of the carrier glass 200. Subsequently, the carrier glass 200 and the light-emitting elements 10c and 10d fixed to the lower surface of the carrier glass 200 are transported above the wiring substrate 20 by any transport means. As shown in FIG. 10, each of the light-emitting elements 10c and 10d is disposed above the wiring substrate 20 via a holding member 28. At this time, the electrode 12 included in each of the light-emitting elements 10c and 10d and the conductive member 13 provided on the upper surface of the wiring portion 22 face each other with a gap therebetween.

[0069] Next, in the step of bringing the conductive member 13 into contact with the electrode 12, the light-emitting elements 10c and 10d held by the holding member 28 and the wiring substrate 20 are each transported into the chamber 710 of the heating device 700. Subsequently, ozone gas is supplied into the chamber 710 heated to a temperature below the melting point of the conductive member 13. The lower surface of the electrode 12 and the upper surface of the conductive member 13 are cleaned by the ozone gas supplied into the chamber 710. Also, the holding member 28 is removed by the ozone gas supplied into the chamber 710. As a result, the electrode 12 and the conductive member 13 facing each other come into contact.

[0070] Subsequently, in the step of joining the electrode 12 and the wiring portion 22, for example, the temperature in the chamber 710 is further increased, the conductive member 13 is heated to a temperature equal to or higher than the melting point of the conductive member 13, and the electrode 12 and the wiring portion 22 are joined. Through these steps, a light-emitting device according to a modified example is obtained.

[0071] Also, with the manufacturing method of the light-emitting device according to the modified example, both the electrode 12 and the wiring portion 22 can be joined in a state where the distance therebetween is short. As a result, the joinability between the light-emitting element 10 and the wiring substrate 20 can be improved. In addition, the yield of the light-emitting device can be improved. Further, since the distance between the electrode 12 and the wiring portion 22 is short, the electrical resistance of the conductor portion including the conductive member 13, the electrode 12, and the wiring portion 22 can be reduced. Also, the holding member 28 can be removed at the same timing as the step of cleaning the lower surface of the electrode 12 and the upper surface of the conductive member 13 with ozone gas. Therefore, it is not necessary to separately provide a step of removing the holding member 28, and the number of steps for manufacturing the light-emitting device can be reduced.

[0072] As described above, the preferred embodiments and the like have been described in detail, but the present invention is not limited to the above-described embodiments and the like, and various modifications and substitutions can be made to the above-described embodiments without departing from the scope described in the claims.

[0073] Aspects of the present disclosure are, for example, as follows. <Item 1> A step of preparing a plurality of light-emitting elements including a semiconductor structure, an electrode disposed on a lower surface of the semiconductor structure, and a conductive member provided on a lower surface of the electrode. A step of disposing a plurality of the light-emitting elements via a holding member above a wiring substrate including a base material and a plurality of wiring portions provided on an upper surface side of the base material, the step of disposing the plurality of light-emitting elements such that the conductive member included in each of the plurality of light-emitting elements faces each of the wiring portions with a gap therebetween. A step of removing the holding member with ozone gas in a temperature environment lower than the melting point of the conductive member and bringing the conductive member into contact with the wiring portion. A step of heating the conductive member to a temperature equal to or higher than the melting point of the conductive member and joining the electrode and the wiring portion; A method for manufacturing a light-emitting device, including the above. <Item 2> A step of preparing a plurality of light-emitting elements including a semiconductor structure and an electrode disposed on the lower surface of the semiconductor structure; A step of disposing a plurality of the light-emitting elements via a holding member above a wiring substrate including a base material, a plurality of wiring portions provided on the upper surface side of the base material, and a conductive member provided on the upper surface of the wiring portion, wherein the conductive member included in the wiring substrate is disposed so as to face the electrode of each light-emitting element with a gap therebetween; A step of removing the holding member with ozone gas in a temperature environment lower than the melting point of the conductive member and bringing the conductive member into contact with the electrode; A step of heating the conductive member to a temperature equal to or higher than the melting point of the conductive member and joining the electrode and the wiring portion; A method for manufacturing a light-emitting device, including the above. <Item 3> The conductive member is a eutectic material. The method for manufacturing a light-emitting device according to <Item 1> or <Item 2> above. <Item 4> In the step of bringing the conductive member into contact, ozone gas is supplied into a chamber that houses a plurality of the light-emitting elements and the wiring substrate. In the step of joining the electrode and the wiring portion, while leaving a plurality of the light-emitting elements and the wiring substrate in the chamber, the temperature in the chamber is raised to a temperature equal to or higher than the melting point of the conductive member. The method for manufacturing a light-emitting device according to any one of <Item 1> to <Item 3> above. <Item 5> The electrodes of each light-emitting element include a first electrode and a second electrode respectively disposed on the lower surface of the semiconductor structure. In the step of preparing a plurality of the light-emitting elements, after forming the conductive member on each of the lower surfaces of the first electrode and the second electrode, the lower surface side of each conductive member is shaved. The method for manufacturing a light-emitting device according to <Item 1> above. <Item 6> In the step of arranging the plurality of light-emitting elements, the plurality of light-emitting elements fixed to the lower surface of the carrier glass via a resin layer are transferred above the wiring substrate. <Item 7> In the step of bringing the conductive member into contact, without separating the carrier glass from the plurality of light-emitting elements, the plurality of light-emitting elements, the wiring substrate, and the carrier glass are transferred into the chamber, and at least a part of the resin layer is removed by the ozone gas supplied into the chamber. The method for manufacturing a light-emitting device according to any one of <Item 1> to <Item 5>. <Item 7> In the step of arranging the plurality of light-emitting elements, after transferring the plurality of light-emitting elements fixed to the carrier glass above the wiring substrate, the carrier glass is separated from the plurality of light-emitting elements, and a weight member is placed on the upper surface of the semiconductor structure. The method for manufacturing a light-emitting device according to any one of <Item 1> to <Item 5>. <Item 8> In the step of bringing the conductive member into contact, the temperature in the chamber is set to 150°C or lower, and ozone gas of 80 vol% or more is supplied into the chamber. The method for manufacturing a light-emitting device according to <Item 4>. <Item 9> In the step of bringing the conductive member into contact, ethylene gas is further added into the chamber. The method for manufacturing a light-emitting device according to <Item 4>. <Item 10> In the step of joining the electrode and the wiring portion, a reducing gas containing formic acid is further supplied into the chamber. The method for manufacturing a light-emitting device according to any one of <Item 1> to <Item 9>.

Explanation of Reference Numerals

[0074] 1 Light-emitting device 10(10a, 10b, 10c, 10d) Light-emitting element 11(11a, 11b) Semiconductor structure 12(12a1, 12a2, 12b1, 12b2) Electrode 13(13a1, 13a2, 13b1, 13b2) Conductive member 20 Wiring Substrate 21 Base Material 22(22a1, 22a2, 22b1, 22b2) Wiring Portion 40 Wavelength Conversion Member 50 Light Shielding Member 60 Conductor Fine Wire 70 Package Substrate 80 Coating Member 200 Carrier Glass 700 Heating Device 710 Chamber

Claims

1. A step of preparing a plurality of light-emitting elements, comprising a semiconductor structure, an electrode disposed on the lower surface of the semiconductor structure, and a conductive member provided on the lower surface of the electrode; A step of disposing a plurality of the light-emitting elements via a holding member above a wiring substrate including a base material and a plurality of wiring portions provided on the upper surface side of the base material, wherein the conductive members included in the plurality of light-emitting elements are disposed such that each of the conductive members faces each of the wiring portions with a gap therebetween; A step of removing the holding member with ozone gas in a temperature environment below the melting point of the conductive member and bringing the conductive member into contact with the wiring portion; A step of heating the conductive member to a temperature equal to or higher than the melting point of the conductive member to join the electrode and the wiring portion; A method for manufacturing a light-emitting device, including the above steps.

2. A step of preparing a plurality of light-emitting elements, comprising a semiconductor structure and an electrode disposed on the lower surface of the semiconductor structure; A step of disposing a plurality of the light-emitting elements via a holding member above a wiring substrate including a base material, a plurality of wiring portions provided on the upper surface side of the base material, and a conductive member provided on the upper surface of the wiring portion, wherein the conductive member included in the wiring substrate faces the electrode of each of the light-emitting elements with a gap therebetween; A step of removing the holding member with ozone gas in a temperature environment below the melting point of the conductive member and bringing the conductive member into contact with the electrode; A step of heating the conductive member to a temperature equal to or higher than the melting point of the conductive member to join the electrode and the wiring portion; A method for manufacturing a light-emitting device, including the above steps.

3. The conductive member is a eutectic material. The method for manufacturing a light-emitting device according to claim 1 or claim 2.

4. In the step of bringing the conductive member into contact, ozone gas is supplied into a chamber that houses the plurality of light-emitting elements and the wiring substrate. In the step of joining the electrode and the wiring portion, with the plurality of light-emitting elements and the wiring substrate remaining in the chamber, the temperature in the chamber is raised to a temperature equal to or higher than the melting point of the conductive member. The method for manufacturing a light-emitting device according to claim 1 or claim 2.

5. The electrodes of the respective light-emitting elements include a first electrode and a second electrode that are respectively disposed on the lower surface of the semiconductor structure. In the step of preparing a plurality of the light-emitting elements, after forming the conductive member on each of the lower surfaces of the first electrode and the second electrode, the lower surface side of each conductive member is shaved. The method for manufacturing a light-emitting device according to claim 1.

6. In the step of arranging a plurality of the light-emitting elements, a plurality of the light-emitting elements fixed to the lower surface of a carrier glass via a resin layer are transferred above the wiring substrate. In the step of bringing the conductive member into contact, without separating the carrier glass from the plurality of light-emitting elements, the plurality of light-emitting elements, the wiring substrate, and the carrier glass are transferred into a chamber, and at least a part of the resin layer is removed by the ozone gas supplied into the chamber. The method for manufacturing a light-emitting device according to claim 1 or claim 2.

7. In the step of arranging a plurality of the light-emitting elements, after transferring a plurality of the light-emitting elements fixed to a carrier glass above the wiring substrate, the carrier glass is separated from the plurality of light-emitting elements, and a weight member is placed on the upper surface of the semiconductor structure. The method for manufacturing a light-emitting device according to claim 1 or claim 2.

8. In the step of bringing the conductive member into contact, the temperature in the chamber is set to 150°C or lower, and ozone gas of 80 vol% or more is supplied into the chamber. The manufacturing method of the light-emitting device according to claim 4.

9. In the step of bringing the conductive member into contact, ethylene gas is further added into the chamber. The manufacturing method of the light-emitting device according to claim 4.

10. In the step of joining the electrode and the wiring portion, a reducing gas containing formic acid is further supplied into the chamber. The manufacturing method of the light-emitting device according to claim 1 or claim 2.

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