JP2015073060A - Light emitting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light emitting device which can reduce heat resistance between an LED chip and a mounting substrate.SOLUTION: A light emitting device B comprises a mounting substrate 2a including a first conductor part 21 and a second conductor part 22, and an LED chip 1a including a first electrode 14 formed on a surface 11a of a first conductivity type semiconductor layer 11 and a second electrode 15 formed on a surface 12a of a second conductivity type semiconductor layer 12. The light emitting device B1 includes a projection structure 16 which projects one of a surface 12a side of the second conductivity type semiconductor layer 12 and a surface 22a side of the second conductor part 22 to the other side to contact the other side, and which lies along an outer periphery of the second electrode 15. The light emitting device B1 is formed in a manner such that the first electrode 14 and the first conductor part 21 are bonded by a first bond part 31 formed by a solder, and the second electrode 15 and the second conductor part 22 are bonded by a second bond part 32 formed by a solder, and the second bond part 32 fills a space 3 surrounded by the second electrode 12, the projection structure 16 and the second conductor part 22.

Description

  The present invention relates to a light emitting device including an LED chip (light emitting diode chip).

  As a light emitting device, for example, a light emitting device 100 having a configuration shown in FIG. 29 is known (Patent Document 1).

  The light emitting device 100 includes an LED chip 101 and a mounting substrate 102 on which the LED chip 101 is mounted.

  The LED chip 101 has a stacked structure of an n-type nitride semiconductor layer 112, a nitride light-emitting layer 113, and a p-type nitride semiconductor layer 114 on one surface side of the translucent substrate 111. In the LED chip 101, an anode electrode 107 is formed on the side of the p-type nitride semiconductor layer 114 opposite to the nitride light emitting layer 113 side. In the LED chip 101, a cathode electrode 108 is formed on the n-type nitride semiconductor layer 112 on the laminated light emitting layer 113 side.

  The mounting substrate 102 has conductor patterns 127 and 128 formed on one surface side of the insulating substrate 121. In the LED chip 101, the anode electrode 107 is bonded to the conductor pattern 127 through a plurality of bumps 137. In the LED chip 101, the cathode electrode 108 is bonded to the conductor pattern 128 via one bump 138.

  Further, as a light emitting device, for example, an LED device (semiconductor light emitting device) 210 having a configuration shown in FIG. 30 is known (Patent Document 2).

  The LED device 210 includes a circuit board 212 and LED elements 213 flip-chip mounted on the circuit board 212.

  In the circuit board 212, a negative electrode 214 (first electrode) and a positive electrode 215 (second electrode) are formed on a plate material 216.

  The LED element 213 includes a sapphire substrate 225, an n-type semiconductor layer 221 (first semiconductor layer), a light emitting layer (not shown), and a p-type semiconductor layer 222 (second semiconductor layer). The LED element 213 includes an n-side bump 223 (first bump) connected to the n-type semiconductor layer 221 and a p-side bump 224 (second bump) connected to the p-type semiconductor layer 222. Yes. The n-side bump 223 has a smaller plane area than the p-side bump 224. The n-side bump 223 and the p-side bump 224 are composed of an Au bump portion and a gold-tin eutectic layer. The n-side bump 223 and the p-side bump 224 have a thickness of 10 to 15 μm. The thickness of the gold tin eutectic layer is 2 to 3 μm. There is a step of about 1 μm corresponding to the thickness of the p-type semiconductor layer 222 between the lower surfaces of the n-side bump 223 and the p-side bump 224.

  The n-side bump 223 and the p-side bump 224 of the LED element 213 are connected to the negative electrode 214 and the positive electrode 215 of the circuit board 212, respectively. In the circuit board 212, a correction film 217 is formed in the connection region of the n-side bump 223 in the negative electrode 214. The correction film 217 is formed to have a thickness (approximately 1 μm) substantially equal to the above-described step.

  Since the LED device 210 includes the correction film 217, the gold-tin alloy protruding from the connection region of the p-side bump 224 can be reduced. In addition, since the LED device 210 does not need to forcefully crush the p-side bumps 224 in the bonding process of mounting the LED elements 213 on the circuit board 212, the LED device 210 can be added in the bonding process compared to the case where the correction film 217 is not provided. There is an advantage that the pressure can be reduced.

JP 2010-199247 A JP 2011-204838 A

  In the field of light emitting devices, it is desired to improve reliability by improving heat dissipation.

  On the other hand, in the light emitting device 100, it is difficult to further reduce the thermal resistance between the LED chip 101 and the mounting substrate 102.

  In addition, the LED device 210, in the bonding process, aligns the circuit board 212 and the LED element 213 at the time of manufacturing, and then pressurizes from the LED element 213 side, and heats from the circuit board 212 side, thereby causing an n-side bump. It is necessary to melt the gold-tin eutectic layer of each of 223 and p-side bump 224. For this reason, in the LED device 210, the thickness of each of the n-side bump 223 and the p-side bump 224 is likely to vary, and the thermal resistance is likely to vary.

  This invention is made | formed in view of the said reason, The objective is to provide the light-emitting device which can aim at reduction of the thermal resistance between a LED chip and a mounting substrate.

The light emitting device of the present invention includes a mounting substrate, and an LED chip mounted on the mounting substrate,
The mounting substrate includes a support, and a first conductor portion and a second conductor portion that are supported by the support and to which the LED chip is electrically connected. The LED chip includes a substrate and the substrate. A first conductivity type semiconductor layer formed on the first surface side; a second conductivity type semiconductor layer formed on the opposite side of the first conductivity type semiconductor layer from the substrate side; and the first conductivity type semiconductor layer. And a second electrode formed on the surface of the second conductivity type semiconductor layer, the second conductivity type semiconductor comprising: a first electrode formed on an exposed surface opposite to the substrate side of the second conductivity type semiconductor layer; A protruding structure portion that protrudes from at least one of the surface side of the layer and the surface side of the second conductor portion to the other side, contacts the other side, and is positioned along the outer periphery of the second electrode; The first electrode and the first conductor portion are formed with solder. The second electrode and the second conductor portion are joined by a second joint portion formed by solder, and the second joint portion includes the second electrode, the protruding structure portion, and the It is formed so that the space enclosed with the 2nd conductor part may be satisfy | filled.

  In the light emitting device, the protrusion structure portion is formed along an outer periphery of the second electrode in the LED chip, and on the surface side of the second conductivity type semiconductor layer, the protrusion structure portion of the LED chip. It is preferable to protrude from the periphery.

  In this light emitting device, it is preferable that the LED chip has the second electrode larger than the first electrode, and the protruding structure portion is formed over the entire outer periphery of the second electrode.

  In this light emitting device, it is preferable that the mounting substrate has a thickness of the first conductor portion and the second conductor portion that is larger than an interval between the second electrode and the second conductor portion.

  In this light emitting device, the LED chip includes an insulating film formed on the surface of the second conductive type semiconductor layer so as to surround a contact region of the second electrode with the second conductive type semiconductor layer, The second electrode is formed across the surface of the second conductive type semiconductor layer and the surface of the insulating film, and protrudes in a direction away from the second conductive type semiconductor layer from the center of the second electrode. It is preferable that the outer peripheral portion that has been used also serves as the protruding structure portion.

  In this light emitting device, the LED chip includes an insulating film formed on the surface of the second conductive type semiconductor layer so as to surround a contact region of the second electrode with the second conductive type semiconductor layer, It is preferable that the insulating film also serves as the protruding structure portion.

  In the light emitting device, the protrusion structure portion is formed in a shape along the outer periphery of the second electrode in the second conductor portion, and the protrusion structure portion in the mounting substrate on the surface side of the second conductor portion. It is preferable that it protrudes from the periphery.

  In the light emitting device, the LED chip has a shape in which the second electrode is larger than the first electrode, and the protruding structure portion extends along the entire outer periphery of the second electrode in the second conductor portion. Preferably it is formed.

  In this light emitting device, it is preferable that the protruding structure portion is formed of the same material as a portion of the second conductor portion to be joined to the second joint portion, and is joined to the second joint portion.

  In this light emitting device, it is preferable that the protruding structure portion has lower solder wettability than the second conductor portion and is not joined to the second joint portion.

  In this light emitting device, it is preferable that the solder forming the first joint and the solder forming the second joint are AuSn.

  In the light emitting device, the first conductor portion in the second conductor portion is configured such that a gap between the first conductor portion and the second conductor portion is wider than a gap between the first electrode and the second electrode. It is preferable that a side end of the second electrode is set back relative to the end of the second electrode on the first electrode side.

  The light emitting device of the present invention protrudes from at least one of the surface side of the second conductivity type semiconductor layer and the surface side of the second conductor portion to the other side, contacts the other side, and A projecting structure portion positioned along an outer periphery, wherein the first electrode and the first conductor portion are joined by a first joint portion formed of solder, and the second electrode and the second conductor portion are joined together; The second joint portion is formed by soldering, and the second joint portion is formed to fill a space surrounded by the second electrode, the protruding structure portion, and the second conductor portion. Therefore, it becomes possible to reduce the thermal resistance between the LED chip and the mounting substrate.

FIG. 1 is a schematic cross-sectional view of a main part of the light emitting device according to the first embodiment. FIG. 2 is a schematic plan view of a main part of the light emitting device according to the first embodiment. FIG. 3 is a schematic plan view of an LED chip in the light emitting device of the first embodiment. FIG. 4 is an explanatory diagram of a method for manufacturing the light emitting device of the first embodiment. FIG. 5 is an explanatory diagram of the method for manufacturing the light emitting device of the first embodiment. FIG. 6 is an explanatory diagram of the method for manufacturing the light emitting device of the first embodiment. FIG. 7 is an explanatory diagram of the method for manufacturing the light emitting device of the first embodiment. FIG. 8 is a main part schematic plan view of a second modification of the light emitting device of the first embodiment. FIG. 9 is a schematic plan view of an LED chip in a second modification of the light emitting device of the first embodiment. FIG. 10 is an explanatory diagram of a manufacturing method of the second modification of the light emitting device of the first embodiment. FIG. 11 is a schematic plan view of an LED chip in a third modification of the light emitting device of the first embodiment. FIG. 12 is a schematic cross-sectional view of a main part of the light emitting device according to the second embodiment. FIG. 13 is a schematic plan view of a main part of the light emitting device according to the second embodiment. FIG. 14 is a schematic plan view of an LED chip in the light emitting device of the second embodiment. FIG. 15 is an explanatory diagram of a method for manufacturing the light emitting device of the second embodiment. FIG. 16 is an explanatory diagram of a method for manufacturing the light emitting device of the second embodiment. FIG. 17 is an explanatory diagram of a method for manufacturing the light emitting device of the second embodiment. FIG. 18 is an explanatory diagram of a method for manufacturing the light emitting device of the second embodiment. FIG. 19 is a schematic plan view of a main part of a first modification of the light emitting device of the second embodiment. FIG. 20 is a schematic plan view of an LED chip in a first modification of the light emitting device of the second embodiment. FIG. 21 is an explanatory diagram of the manufacturing method of the first modification of the light emitting device of the second embodiment. FIG. 22 is an explanatory diagram of a manufacturing method of the second modification of the light emitting device of the second embodiment. FIG. 23 is a schematic plan view of an LED chip in a second modification of the light emitting device of the second embodiment. FIG. 24 is a main part schematic cross-sectional view of a third modification of the light emitting device of the second embodiment. FIG. 25 is a main part schematic cross-sectional view of a fourth modification of the light emitting device of the second embodiment. FIG. 26 is a main part schematic cross-sectional view of a fifth modification of the light emitting device of the second embodiment. FIG. 27 is a main part schematic cross-sectional view of a sixth modification of the light emitting device of the second embodiment. FIG. 28 is an explanatory diagram of a manufacturing method of the sixth modification of the light emitting device of the second embodiment. FIG. 29 is a schematic cross-sectional view of a conventional light emitting device. FIG. 30 is a schematic cross-sectional view of a conventional LED device.

(Embodiment 1)
Below, light-emitting device B1 of this embodiment is demonstrated based on FIGS. 1 is a schematic schematic cross-sectional view corresponding to the XX cross section of FIG.

  The light emitting device B1 includes a mounting substrate 2a and an LED chip 1a mounted on the mounting substrate 2a. The mounting substrate 2a includes a support 20, and a first conductor portion 21 and a second conductor portion 22 that are supported by the support 20 and electrically connected to the LED chip 1a. The LED chip 1a includes a substrate 10, a first conductive semiconductor layer 11 formed on the first surface 10a side of the substrate 10, and a first conductive semiconductor layer 11 formed on the opposite side of the first conductive semiconductor layer 11 from the substrate 10 side. Two-conductivity-type semiconductor layer 12, first electrode 14 formed on exposed surface 11a opposite to substrate 10 side in first-conductivity-type semiconductor layer 11, and on surface 12a of second-conductivity-type semiconductor layer 12 And a second electrode 15 formed on the substrate. The light emitting device B1 protrudes from one of the surface 12a side of the second conductivity type semiconductor layer 12 and the surface 22a side of the second conductor portion 22 to the other side, contacts the other side, and extends along the outer periphery of the second electrode 15. The protrusion structure portion 16 is provided. In the light emitting device B1, the first electrode 14 and the first conductor portion 21 are joined by the first joint portion 31 formed by solder, and the second electrode 15 and the second conductor portion 22 are formed by solder. It is joined by the second joining part 32 made. The second joint portion 32 is formed so as to fill the space 3 surrounded by the second electrode 15, the protruding structure portion 16, and the second conductor portion 22. Therefore, the light emitting device B1 can make each of the first joint portion 31 and the second joint portion 32 thinner, and each of the first joint portion 31 and the second joint portion 32 includes the first conductor portion 21 and the first conductor portion 21. It becomes possible to join each of the two conductor portions 22 on the surface. As a result, the light emitting device B1 can reduce the thermal resistance between the LED chip 1a and the mounting substrate 2a. Furthermore, since the light emitting device B1 can manage the thickness of the second joint portion 32 by the protruding structure portion 16, it is possible to reduce variation in thermal resistance. In short, the light emitting device B1 can reduce variations in thermal resistance among products. As a result, the light emitting device B1 can improve heat dissipation and reliability.

  The protruding structure 16 is formed along the outer periphery of the second electrode 15 in the LED chip 1a, and protrudes from the surface 12a side of the second conductive semiconductor layer 12 more than the periphery of the protruding structure 16 in the LED chip 1a. Preferably it is. As a result, in the light emitting device B1, the protruding structure portion 16 is in contact with the surface 22a of the second conductor portion 22, and the second joint portion 32 is surrounded by the second electrode 15, the protruding structure portion 16, and the second conductor portion 22. It is possible to adopt a configuration formed to fill the space 3.

  The solder that forms the first joint 31 and the solder that forms the second joint 32 are preferably AuSn. Accordingly, the light emitting device B1 employs, for example, SnCuAg, which is a kind of lead-free solder other than AuSn, as the solder that forms the first joint 31 and the solder that forms the second joint 32. The heat resistance can be improved as compared with the case of doing so. Therefore, for example, when the light-emitting device B1 is secondarily mounted on a printed wiring board or the like, it is possible to prevent the first bonding portion 31 and the second bonding portion 32 from being remelted during the second mounting. .

  The solder that forms the first joint portion 31 and the solder that forms the second joint portion 32 are not limited to AuSn, and may be, for example, AuSn, SnAgCu, AuGe, AuSi, PbSn, or the like.

  In this specification, for convenience of explanation, after describing a method for manufacturing the light emitting device B1, each component of the light emitting device B1 will be described in detail.

  In the method for manufacturing the light emitting device B1 of the present embodiment, first, after preparing the LED chip 1a and the mounting substrate 2a, the first step and the second step are sequentially performed.

  In the first step, as shown in FIGS. 4 and 5, the first joint portion 31 and the second joint portion 32 are provided on the surface 21 a side of the first conductor portion 21 and the surface 22 a side of the second conductor portion 22 of the mounting substrate 2 a. A first solder layer 41 and a second solder layer 42 are formed as a basis for each. As the solder that is the material of the first solder layer 41 and the second solder layer 42, for example, AuSn can be adopted. The first solder layer 41 and the second solder layer 42 can be formed by, for example, vapor deposition or plating. In the first step, the thicknesses of the first solder layer 41 and the second solder layer 42 are set to the same value. The area of the surface 41a of the first solder layer 41 is set smaller than the area of the surface 14a of the first electrode 14 (see FIG. 3). The area of the surface 42a of the second solder layer 42 is set smaller than the area of the surface 15a of the second electrode 15 (see FIG. 3). The thickness of the 1st solder layer 41 and the 2nd solder layer 42 is the protrusion amount H1 (refer FIG. 6) of the protrusion structure part 16 of LED chip 1a, and the 2nd electrode 15 and 1st electrode in the thickness direction of LED chip 1a. 14 is set to be larger by a predetermined thickness (α) than the sum (H1 + H2) of the step H2 with respect to 14 (see FIG. 6). That is, the thicknesses of the first solder layer 41 and the second solder layer 42 are set to H1 + H2 + α. For example, when H1 = 1 μm and H2 = 1 μm, the thicknesses of the first solder layer 41 and the second solder layer 42 may be set to about 3 μm. In this case, α is 1 μm. These numerical values are merely examples, and may be set as appropriate based on the structure of the LED chip 1a and the like, and are not particularly limited. The first solder layer 41 and the second solder layer 42 are preferably formed at the center of the region of the mounting substrate 2a that faces the first electrode 14 and the second electrode 15, respectively. The second solder layer 42 is disposed on the surface 22 a of the second conductor portion 22 so as to be located inside the vertical projection region of the protruding structure portion 16 and away from the vertical projection region. The vertical projection region of the projection structure 16 means a projection region in the thickness direction of the projection structure 16.

  In the case of AuSn, the first solder layer 41 and the second solder layer 42 have a composition ratio that is smaller than the eutectic composition (70 at% Au, 30 at% Sn) and melts at a temperature of, for example, 300 ° C. or more and less than 400 ° C. AuSn (for example, 60 at% Au, 40 at% Sn) is preferable. The first solder layer 41 and the second solder layer 42 are not limited to AuSn, and are formed of solder lower than the melting point of the mounting substrate 2a and the LED chip 1a.

  In the first step, the first barrier layer 51 and the second barrier layer 52 are formed between the first conductor portion 21 and the second conductor portion 22 and the first solder layer 41 and the second solder layer 42, respectively. preferable. The first barrier layer 51 and the second barrier layer 52 are diffusion of metal (for example, Sn) between the first solder layer 41 and the second solder layer 42 and the first conductor portion 21 and the second conductor portion 22. It is a layer having a function of a diffusion barrier that suppresses variation in the composition of AuSn due to the above. As a material of the first barrier layer 51 and the second barrier layer 52, for example, Pt can be adopted, but not limited thereto, Pd or the like can also be adopted. In the first step, the thicknesses of the first barrier layer 51 and the second barrier layer 52 are set to the same value. The thicknesses of the first barrier layer 51 and the second barrier layer 52 are preferably set to about 0.2 μm, for example. The first barrier layer 51 and the second barrier layer 52 can be formed by, for example, a vapor deposition method or a plating method.

  In the first step, it is preferable to form the first Au layer 61 and the second Au layer 62 on the first solder layer 41 and the second solder layer 42, respectively. In FIG. 5, the first Au layer 61 and the second Au layer 62 are not shown. The first Au layer 61 and the second Au layer 62 are layers provided to suppress Sn oxidation of the first solder layer 41 and the second solder layer 42. The thicknesses of the first Au layer 61 and the second Au layer 62 are preferably sufficiently thinner than the thicknesses of the first solder layer 41 and the second solder layer 42, for example, 0.1 μm or less. The thicknesses of the first Au layer 61 and the second Au layer 62 are such that when the first solder layer 41 and the second solder layer 42 are melted, Au is thermally diffused into the first solder layer 41 and the second solder layer 42. It is necessary to set so that the first conductor portion 21 and the second conductor portion 22 are joined to the first electrode 14 and the second electrode 15. The thicknesses of the first Au layer 61 and the second Au layer 62 are preferably set in the range of about 0.05 μm to 0.1 μm, for example. The first Au layer 61 and the second Au layer 62 can be formed by, for example, vapor deposition or plating. Hereinafter, the laminated film of the first barrier layer 51, the first solder layer 41, and the first Au layer 61 will be referred to as a first bonding layer 71, and the second barrier layer 52, the second solder layer 42, and the second Au layer 62 will be described. The laminated film is referred to as a second bonding layer 72. The first bonding layer 71 only needs to include at least the first solder layer 41 and is not limited to a laminated film but may be a single layer film. The second bonding layer 72 only needs to include at least the second solder layer 42 and is not limited to a laminated film but may be a single layer film.

  In the second step, the first step and the second step are sequentially performed. In the second step, a die bonding apparatus (not shown) is used. The die bonding apparatus includes, for example, a suction holder that can hold the LED chip 1a by suction, a stage on which the mounting substrate 2a is placed, a first heater that is provided on the stage and can heat the mounting substrate 2a, and a suction holder. Or the thing of the structure provided with the 2nd heater with which either of the holder holding an adsorption | suction holder was equipped is preferable. Examples of the suction holding tool include a collet.

  In the first step, as shown in FIG. 6, the LED chip 1a and the mounting substrate 2a are opposed to each other. The LED chip 1a and the mounting substrate 2a are opposed to each other so that the first electrode 14 and the second electrode 15 of the LED chip 1a and the first conductor portion 21 and the second conductor portion 22 of the mounting substrate 2a are opposed to each other. This means that the LED chip 1a and the mounting substrate 2a are opposed to each other.

  In the first step, the first electrode 14 and the second electrode 15 of the LED chip 1a sucked and held by the suction holder are made to face the first conductor portion 21 and the second conductor portion 22 of the mounting substrate 2a.

  In the second step, the first electrode 14 and the second electrode 15 of the LED chip 1a and the first conductor portion 21 and the second conductor portion 22 of the mounting substrate 2a are joined by the first joint portion 31 and the solder formed by solder. Joining is performed by the formed second joining portion 32. The 1st junction part 31 may contain the 1st barrier layer 51 in addition to the case where it forms only with solder, in addition to the part formed with solder. Moreover, the 2nd junction part 32 may contain the 2nd barrier layer 52 in addition to the case where it forms only with solder, in addition to the part formed with solder.

  In the second step described above, the first electrode 14 and the second electrode 15 of the LED chip 1a are superposed so that the first bonding layer 71 and the second bonding layer 72 on the mounting substrate 2a are in contact with each other. The first solder layer 41 and the second solder layer 42 are melted while performing appropriate heating and pressing. When the first solder layer 41 is melted, Au diffuses from the first Au layer 61 into the melted solder, and the composition ratio of Au in the melted solder increases. Further, when the second solder layer 42 is melted, Au diffuses from the second Au layer 62 into the melted solder, and the composition ratio of Au in the melted solder increases.

  In the second step, after the first solder layer 41 and the second solder layer 42 are melted as described above, pressure is applied from the LED chip 1 a side so that the protruding structure portion 16 contacts the second conductor portion 22. Then, the molten solder is pushed down and spread laterally to fill the space 3 with the solder, and then cooled and solidified.

In the second step, only the mounting substrate 2a may be heated by the first heater, or the LED chip 1a may be heated by the second heater mounted on the collet or the holder holding the collet. In the second step, it is preferable to perform heating from both the first heater and the second heater in consideration of the bonding property between the mounting substrate 2a and the LED chip 1a. In the second step, pressurization is performed by applying an appropriate load. For example, the load is preferably set in a range of about 0.1 to 1 kg / cm ² for one LED chip 1a. Moreover, it is preferable to set the time which applies a load in the range of about 0.1 to 1 second, for example. The second step is preferably performed in an N ₂ gas atmosphere or a vacuum atmosphere.

  The melting temperature of the first solder layer 41 and the second solder layer 42 is preferably lower than the heat resistant temperature of the LED chip 1a. In order to lower the melting temperature of the first solder layer 41 and the second solder layer 42, it is better that the composition ratio of Au is a composition ratio near the eutectic composition. For example, the composition ratio of Au is 68 at% to 69 at%. If present, the melting temperature becomes 300 ° C. or lower. In order to melt the first solder layer 41 and the second solder layer 42 at 400 ° C. or lower, when the solder forming the first solder layer 41 and the solder forming the second solder layer 42 are AuSn, for example, the composition of Au The ratio may be 56 at% or more and less than 70 at%.

  By the way, the volume of the second bonding layer 72 formed in the first step is preferably set to be equal to the volume of the space 3 so that the solder forming the second bonding portion 32 does not come out of the space 3. .

  In the method for manufacturing the light-emitting device B1, the molten solder so that the protruding structure portion 16 of the LED chip 1a contacts the surface 22a of the second conductor portion 22 in a state where the first solder layer 41 and the second solder layer 42 are melted. Is pressed down to join the LED chip 1a and the mounting substrate 2a. Therefore, in the manufacturing method of light-emitting device B1, it becomes possible to suppress that the 1st electrode 14 and the 1st conductor part 21 become unjoined.

  Further, in the method for manufacturing the light emitting device B1, the protruding structure portion 16 is in contact with the second conductor portion 22, and the first electrode 14 and the first conductor portion 21 are joined by the first joining portion 31 formed of solder, The 2nd electrode 15 and the 2nd conductor part 22 are joined by the 2nd junction part 32 formed of solder. Thereby, in the manufacturing method of the light emitting device B1, the second joint portion 32 is formed so as to fill the space 3 surrounded by the second electrode 15, the protruding structure portion 16, and the second conductor portion 22, and It becomes possible to do. In the manufacturing method of the light emitting device B1, when the molten solder of the second bonding layer 72 is pushed down and spread in the lateral direction, the protruding structure 16 causes the molten solder to flow along the surface of the LED chip 1a. Therefore, it is possible to suppress the occurrence of a short circuit due to the solder between the first electrode 14 and the second electrode 15. Moreover, in the method of manufacturing the light emitting device B1, the light emitting device B1 that can reduce the thermal resistance between the LED chip 1a and the mounting substrate 2a and can reduce the variation in the thermal resistance is manufactured. Is possible.

  In the manufacturing method of the light emitting device B1, when the area of the second electrode 15 is larger than the area of the first electrode 14, there is a concern that an unstable spread is more likely to occur in the second joint portion 32 than in the first joint portion 31. There is. For this reason, in the manufacturing method of light-emitting device B1, it is preferable to form the 2nd joining layer 72 in a predetermined pattern. The pattern of the second bonding layer 72 may be appropriately changed depending on the planar shape of the second electrode 15, but for example, as shown in FIGS. 5 and 7, a radial shape that makes it difficult to capture bubbles is preferable. . Thereby, in the manufacturing method of the light emitting device B1, it becomes possible to stabilize the spread when the solder melted in the second step is pushed down and spread, and the generation of voids in the second joint portion 32 can be suppressed. It becomes possible.

  By the way, in the manufacturing method of the light emitting device B1, it is preferable to apply a load so that the entire front end surface of the protruding structure portion 16 is in contact with the surface 22a of the second conductor portion 22. However, in the manufacturing method of the light emitting device B1, due to the difference between the flatness of the front end surface of the protrusion structure portion 16 and the flatness of the surface 22a of the second conductor portion 22, the entire front end surface of the protrusion structure portion 16 is obtained. It may be difficult to make the contact with the surface 22 a of the second conductor portion 22. In this case, a part of the front end surface of the protrusion structure portion 16 is in contact with the surface 22a of the second conductor portion 22, and the remaining portion of the front end surface of the protrusion structure portion 16 and the surface 22a of the second conductor portion 22 are between. In some cases, a thin solder layer made of solder that has been soaked and hardened during manufacturing may remain. In short, the light emitting device B1 may be configured such that the protruding structure portion 16 partially contacts the surface 22a of the second conductor portion 22 as long as the parallelism of the LED chip 1a with respect to the mounting substrate 2a is in a desired range. In the method of manufacturing the light emitting device B1, if the load applied in the second step is increased, the difference between the flatness of the tip surface of the protruding structure 16 and the flatness of the surface 22a of the second conductor portion 22 can be reduced. Thus, the contact area between the protruding structure portion 16 and the second conductor portion 22 can be increased. Further, in the method for manufacturing the light emitting device B1, when the protruding structure 16 is formed of, for example, metal, the protruding structure 16 may be deformed so as to be compressed by increasing the load applied in the second step. Thus, the contact area between the protruding structure portion 16 and the second conductor portion 22 can be increased.

  In the method for manufacturing the light emitting device B1, as described above, it is preferable to form the first Au layer 61 and the second Au layer 62 on the first solder layer 41 and the second solder layer 42, respectively, in the first step. Thereby, in the manufacturing method of light-emitting device B1, it becomes possible to suppress that the Sn of the 1st solder layer 41 and the 2nd solder layer 42 oxidizes before the 2nd process, and LED chip 1a, mounting board 2a, and It becomes possible to improve the bondability. The bondability can be evaluated by, for example, die shear strength. The die shear strength is a force necessary to push and peel the LED chip 1a, which is a die bonded to the mounting substrate 2a, in parallel to the bonding surface. The die shear strength can be measured by, for example, a die shear tester.

  In the method for manufacturing the light emitting device B1, in the first step, as described above, the first bonding layer 71 and the second bonding layer 72 are preferably formed on the mounting substrate 2a side. Thereby, in the manufacturing method of light-emitting device B1, manufacture becomes easy compared with the case where the 1st joining layer 71 and the 2nd joining layer 72 are formed in the LED chip 1a side.

  Each component of the light emitting device B1 will be described in detail below.

  The mounting substrate 2a is a substrate on which the LED chip 1a is mounted. “Mounting” is a concept including arranging and mechanically connecting the LED chips 1a and electrically connecting them. For this reason, the mounting substrate 2a has a function of mechanically holding the LED chip 1a and a function of forming a wiring for supplying power to the LED chip 1a. The mounting substrate 2a includes a first conductor portion 21 and a second conductor portion 22 as wiring. The mounting substrate 2a is configured so that one LED chip 1a can be mounted. The mounting substrate 2a does not particularly limit the number of LED chips 1a that can be mounted, and may be configured to be capable of mounting a plurality of LED chips 1a, for example. The light emitting device B1 may have a configuration in which a plurality of LED chips 1a are connected in series, may have a configuration connected in parallel, or may have a configuration connected in series and parallel. .

  The mounting substrate 2a is configured such that the surface 21a of the first conductor portion 21 and the surface 22a of the second conductor portion 22 are aligned on one plane.

The support body 20 has a function of supporting the first conductor portion 21 and the second conductor portion 22 and a function of electrically insulating the first conductor portion 21 and the second conductor portion 22. The support 20 preferably has a function as a heat sink for efficiently transferring the heat generated in the LED chip 1a to the outside. For this reason, it is preferable that the support body 20 is formed of a material having high thermal conductivity. The support 20 can be composed of, for example, an aluminum nitride substrate. The support 20 is not limited to an aluminum nitride substrate, and may be formed of, for example, a sapphire substrate or a silicon carbide substrate. The support 20 may have a configuration in which an electrical insulating layer is formed on the surface of a silicon substrate, or a configuration in which an electrical insulating layer made of an appropriate material is formed on the surface of a metal plate. The material of the metal plate is preferably a metal having high thermal conductivity. As the material of the metal plate, for example, copper, aluminum, silver, iron, aluminum alloy, phosphor bronze, copper alloy, nickel alloy, Kovar, or the like can be adopted. For example, SiO ₂ or Si ₃ N ₄ can be used as the material of the electrical insulating layer formed on the surface of the silicon substrate.

  In the mounting substrate 2 a, the support 20 is formed in a flat plate shape, and the first conductor portion 21 and the second conductor portion 22 are formed on the first surface 20 a orthogonal to the thickness direction of the support 20. In the mounting substrate 2a, the thickness of the first conductor portion 21 and the thickness of the second conductor portion 22 are set to the same value. The mounting substrate 2a is not limited to a flat plate shape, and for example, the mounting substrate 2a may have a concave portion for housing the LED chip 1a on one side. In this case, the first conductor is formed on the inner bottom surface of the concave portion. The part 21 and the second conductor part 22 may be formed.

  The outer peripheral shape of the support 20 is rectangular. The outer peripheral shape of the support 20 is not limited to a rectangular shape, and may be, for example, a polygonal shape other than a rectangular shape, a circular shape, or the like.

  The first conductor portion 21 is a conductive layer to which the first electrode 14 of the LED chip 1a is electrically connected. The second conductor portion 22 is a conductive layer to which the second electrode 15 of the LED chip 1a is electrically connected.

The first conductor section 21 and the second conductor part 22, for example, can be constituted by a laminated film of a Ti film 21 _1, 22 ₁ and the Pt film 21 _2, 22 ₂ and the Au film 21 _3, 22 _3. The first conductor portion 21 and the second conductor portion 22 are not limited to this, for example, a laminated film of an Al film, a Ni film, a Pd film, and an Au film, a laminated film of a Ni film and an Au film, a Cu film, and a Ni film A laminated film of a film and an Au film or the like can be employed. When the first conductor portion 21 and the second conductor portion 22 are formed of a laminated film, the uppermost layer farthest from the support 20 is formed of Au, and the lowermost layer closest to the support 20 is in close contact with the support 20. It is preferable that it is made of a material having high properties. The 1st conductor part 21 and the 2nd conductor part 22 may be comprised not only with a laminated film but with a single layer film.

  The mounting substrate 2 a is formed with the first conductor portion 21 and the second conductor portion 22 so that the first conductor portion 21 and the second conductor portion 22 are spatially separated. Thereby, the mounting substrate 2 a has a groove 23 formed between the first conductor portion 21 and the second conductor portion 22. The inner surface of the groove 23 is constituted by a part of the first surface 20 a of the support 20 and the opposing surfaces of the first conductor portion 21 and the second conductor portion 22. In the mounting substrate 2 a, the first conductor portion 21 and the second conductor portion 22 are formed on the first surface 20 a of the support body 20 with the same thickness. Thereby, the mounting substrate 2a is configured such that the surface 21a of the first conductor portion 21 and the surface 22a of the second conductor portion 22 are aligned on one plane. The planar size of the mounting substrate 2a is preferably larger than the chip size of the LED chip 1a.

  The chip size of the LED chip 1a is not particularly limited. As the LED chip 1a, for example, the chip size is 0.4 mm □ (0.4 mm × 0.4 mm), 0.6 mm □ (0.6 mm × 0.6 mm), or 0.8 mm □ (0.8 mm × 0. 8 mm) or 1 mm □ (1 mm × 1 mm) can be used. The planar shape of the LED chip 1a is not limited to a square shape, and may be a rectangular shape, for example. When the planar shape of the LED chip 1a is rectangular, the LED chip 1a having a chip size of 0.5 mm × 0.24 mm, for example, can be used.

  The LED chip 1a is provided with a first electrode 14 and a second electrode 15 on one side in the thickness direction of the LED chip 1a. Thereby, the LED chip 1a can be flip-chip mounted on the mounting substrate 2a.

  In the LED chip 1a, on the first surface 10a side of the substrate 10, a first conductive semiconductor layer 11 and a second conductive semiconductor layer 12 are formed in order from the side close to the first surface 10a. In short, the LED chip 1 a includes the semiconductor multilayer film 19 having the first conductive semiconductor layer 11 and the second conductive semiconductor layer 12. In the LED chip 1a, the first conductivity type semiconductor layer 11 is composed of an n-type semiconductor layer, and the second conductivity type semiconductor layer 12 is composed of a p-type semiconductor layer. In the LED chip 1a, the first conductivity type semiconductor layer 11 may be constituted by a p-type semiconductor layer, and the second conductivity type semiconductor layer 12 may be constituted by an n-type semiconductor layer.

  The substrate 10 has a function of supporting the semiconductor multilayer film 19. The semiconductor multilayer film 19 can be formed by an epitaxial growth method. Examples of the epitaxial growth method include crystals such as a metal organic vapor phase epitaxy (MOVPE) method, a hydride vapor phase epitaxy (HVPE) method, and a molecular beam epitaxy (MBE) method. The growth method can be adopted. The semiconductor multilayer film 19 may contain impurities such as hydrogen, carbon, oxygen, silicon, and iron inevitably mixed when the semiconductor multilayer film 19 is formed. The substrate 10 can be composed of a substrate for crystal growth when the semiconductor multilayer film 19 is formed.

  The LED chip 1a is composed of a blue LED chip that emits blue light. When the LED chip 1a is composed of a GaN blue LED chip, for example, a GaN substrate can be adopted as the substrate 10. The substrate 10 may be a substrate formed of a material that can efficiently transmit light emitted from the semiconductor multilayer film 19, and is not limited to a GaN substrate, and may be a sapphire substrate, for example. In short, the substrate 10 is preferably a substrate that is transparent to the light emitted from the semiconductor multilayer film 19. As described above, the LED chip 1a has the first conductive semiconductor layer 11 and the second conductive semiconductor layer 12 formed on the first surface 10a side of the substrate 10. Therefore, in the LED chip 1a, it is preferable that the second surface 10b of the substrate 10 constitutes a light extraction surface. The LED chip 1a may have a configuration in which the semiconductor multilayer film 19 includes a buffer layer (not shown) between the substrate 10 and the first conductivity type semiconductor layer 11. The LED chip 1a does not particularly limit the material and emission color of the semiconductor multilayer film 19. That is, the LED chip 1a is not limited to a blue LED chip, but may be a purple LED chip, an ultraviolet LED chip, a red LED chip, a green LED chip, or the like.

  In the LED chip 1 a, the semiconductor multilayer film 19 preferably includes a light emitting layer 13 between the first conductive type semiconductor layer 11 and the second conductive type semiconductor layer 12. In this case, the light emitted from the semiconductor multilayer film 19 is light emitted from the light emitting layer 13, and the emission wavelength is defined by the material of the light emitting layer 13. The light emitting layer 13 preferably has a single quantum well structure or a multiple quantum well structure, but is not limited thereto. For example, in the LED chip 1a, the first conductive semiconductor layer 11, the light emitting layer 13, and the second conductive semiconductor layer 12 may form a double heterostructure.

  The first conductivity type semiconductor layer 11 is not limited to a single layer structure, and may have a multilayer structure. Further, the second conductivity type semiconductor layer 12 is not limited to a single layer structure, and may have a multilayer structure. The second conductivity type semiconductor layer 12 may have a multilayer structure including, for example, a p-type electron block layer, a p-type semiconductor layer, and a p-type contact layer. In this case, the p-type semiconductor layer is a layer for transporting holes to the light emitting layer 13. The p-type electron blocking layer is a layer for suppressing electrons that have not been recombined with holes in the light emitting layer 13 from leaking (overflowing) to the p-type semiconductor layer side. The composition of the p-type electron blocking layer is preferably set so that the band gap energy is higher than that of the p-type semiconductor layer and the light emitting layer. The p-type contact layer is a layer provided in order to reduce contact resistance with the second electrode 15 and obtain good ohmic contact with the second electrode 15. The p-type electron block layer and the p-type semiconductor layer can be composed of, for example, AlGaN layers having different compositions. Further, the p-type contact layer can be constituted by, for example, a p-type GaN layer.

  The LED chip 1 a is removed by etching a part of the semiconductor multilayer film 19 from the surface 19 a side of the semiconductor multilayer film 19 to the middle of the first conductivity type semiconductor layer 11. In short, the LED chip 1 a has a mesa structure formed by etching a part of the semiconductor multilayer film 19. Thus, in the LED chip 1a, a step is formed between the surface 12a of the second conductivity type semiconductor layer 12 and the surface 11a of the first conductivity type semiconductor layer 11. In the LED chip 1a, the first electrode 14 is formed on the exposed surface 11a of the first conductive semiconductor layer 11, and the second electrode 15 is formed on the surface 12a of the second conductive semiconductor layer 12. . In the LED chip 1a, when the conductivity type (first conductivity type) of the first conductivity type semiconductor layer 11 is n type and the conductivity type (second conductivity type) of the second conductivity type semiconductor layer 12 is p type, The first electrode 14 and the second electrode 15 constitute a negative electrode and a positive electrode, respectively. In the LED chip 1a, when the first conductivity type is p-type and the second conductivity type is n-type, the first electrode 14 and the second electrode 15 constitute a positive electrode and a negative electrode, respectively.

  In the LED chip 1a, the area of the surface 12a of the second conductivity type semiconductor layer 12 is preferably larger than the area of the surface 11a of the first conductivity type semiconductor layer 11. Thereby, the LED chip 1a can widen the region where the second conductive semiconductor layer 12 and the first conductive semiconductor layer 11 overlap each other in the thickness direction, and can improve the light emission efficiency. Become.

  In the LED chip 1 a, the protruding structure portion 16 is formed along the outer periphery of the second electrode 15, and protrudes on the surface 12 a side of the second conductivity type semiconductor layer 12.

  In the LED chip 1 a, the second electrode 15 is preferably larger than the first electrode 14, and the protruding structure 16 is preferably formed over the entire outer periphery of the second electrode 15. Thereby, the light emitting device B1 can further suppress the occurrence of a short circuit between the second electrode 15 and the first electrode 14 due to the solder forming the second joint portion 32 during manufacture. Moreover, when the LED chip 1a is mounted on the mounting substrate 2a, the light emitting device B1 can improve the reproducibility of the shape of the second joint portion 32, and can reduce variations in thermal resistance. The protrusion structure portion 16 is preferably formed along the outer periphery of the second electrode 15 and has a constant width W1 (see FIG. 6). Thereby, the light emitting device B1 suppresses the occurrence of a short circuit due to the solder between the second electrode 15 and the first electrode 14 while increasing the contact area between the second electrode 15 and the second conductivity type semiconductor layer 12. It becomes possible. The width W1 of the protruding structure 16 is preferably set in a range of about 5 μm to 10 μm, for example.

  The LED chip 1 a is preferably formed so that the second electrode 15 covers substantially the entire surface 12 a of the second conductivity type semiconductor layer 12. The substantially entire surface 12a of the second conductivity type semiconductor layer 12 is not limited to the entire surface 12a. For example, when the LED chip 1a includes an insulating film 18 described later and the outer peripheral portion of the surface 12a of the second conductive semiconductor layer 12 is covered with the insulating film 18, the surface 12a of the second conductive semiconductor layer 12 is substantially omitted. The entire surface means a portion of the surface 12a of the second conductivity type semiconductor layer 12 that is not covered with the insulating film 18. In short, the LED chip 1a is preferably formed so that the second electrode 15 covers the surface 12a of the second conductivity type semiconductor layer 12 in a planar shape. Thereby, the light emitting device B1 can improve heat dissipation.

  In the mounting substrate 2a, it is preferable that the thickness of the first conductor portion 21 and the second conductor portion 22 is larger than the distance between the second electrode 15 and the second conductor portion 22. The interval between the second electrode 15 and the second conductor portion 22 means the interval between the center portion of the surface 15a (see FIG. 6) of the second electrode 15 and the surface 22a of the second conductor portion 22. The distance between the second electrode 15 and the second conductor portion 22 can be determined by the protruding amount H1 of the protruding structure portion 16. In other words, the distance between the second electrode 15 and the second conductor portion 22 is substantially the same as the protruding amount H1 of the protruding structure portion 16.

  Therefore, even when the light emitting device B1 is manufactured, even if the solder protrudes from the space 3, the flow rate of the protruding solder can be reduced by the groove 23, and the light emitting device B1 has the second conductor portion at the time of manufacturing. The side surface 22 can function as a solder guiding portion that guides the protruding solder toward the first surface 20 a side of the support 20. Accordingly, the light emitting device B1 can suppress the occurrence of a short circuit between the second electrode 15 and the first electrode 14 due to the solder protruding from the space 3. Note that the first surface 20 a of the support 20 preferably has lower solder wettability than the side surfaces of the first conductor portion 21 and the second conductor portion 22.

  The LED chip 1a preferably includes an insulating film 18 formed on the surface 12a of the second conductivity type semiconductor layer 12 so as to surround a contact region of the second electrode 15 with the second conductivity type semiconductor layer 12. . In the LED chip 1 a, the second electrode 15 is formed across the surface 12 a of the second conductivity type semiconductor layer 12 and the surface of the insulating film 18, and the second conductivity type semiconductor is more than the center portion of the second electrode 15. An outer peripheral portion protruding in a direction away from the layer 12 also serves as the protruding structure portion 16. As a result, the light emitting device B1 can increase the bonding area between the second electrode 15 and the second conductor portion 22, improve heat dissipation, and reduce the contact resistance. It becomes possible.

As a material of the insulating film 18, SiO ₂ is adopted. The material of the insulating film 18 may be any material having electrical insulating properties, and is not limited to SiO _2. For example, Si ₃ N ₄ , Al ₂ O ₃ , TiO ₂ , Ta ₂ O ₅ , ZrO ₂ , Y ₂ O ₃ , CeO ₂ , Nb ₂ O _{5 and the} like can be used. The thickness of the insulating film 18 is set to 1 μm, for example, but is not particularly limited. The insulating film 18 can be formed by, for example, a chemical vapor deposition (CVD) method, a vapor deposition method, a sputtering method, or the like. The insulating film 18 is not limited to a single layer film, and may be a multilayer film. The multilayer film provided as the insulating film 18 may be composed of a dielectric multilayer film for reflecting light generated in the semiconductor multilayer film 19.

  In the LED chip 1a, the insulating film 18 is formed across the surface 19a of the mesa structure (the surface 12a of the second conductivity type semiconductor layer 12), the side surface 19c, and the surface 11a of the first conductivity type semiconductor layer 11. Is preferred. The portion of the insulating film 18 formed on the surface 11a of the first conductive type semiconductor layer 11 is formed in a pattern surrounding the contact region of the first electrode 14 with the first conductive type semiconductor layer 11. Is preferred.

The insulating film 18 preferably has a function as a passivation film for protecting the function of the semiconductor multilayer film 19, and the material thereof is preferably SiO ₂ or Si ₃ N ₄ . Thereby, the light emitting device B1 can improve the reliability.

  In the LED chip 1a, it is preferable that the contact between the first electrode 14 and the second electrode 15, and the first conductive semiconductor layer 11 and the second conductive semiconductor layer 12 is ohmic contact. The ohmic contact means that there is no rectification of current caused by the direction of applied voltage in the contact between the first electrode 14 and the second electrode 15 and the first conductive semiconductor layer 11 and the second conductive semiconductor layer 12. Means contact. The ohmic contact is preferably substantially linear in current-voltage characteristics, and more preferably linear. Moreover, it is preferable that ohmic contact has a smaller contact resistance. In contact between the first electrode 14 and the second electrode 15 and the first conductive semiconductor layer 11 and the second conductive semiconductor layer 12, the first electrode 14, the second electrode 15, the first conductive semiconductor layer 11, The current passing through the interface with the second conductivity type semiconductor layer 12 is considered to be the sum of the thermoelectron emission current over the Schottky barrier and the tunnel current passing through the Schottky barrier. For this reason, when the tunnel current is dominant in the contact between the first electrode 14 and the second electrode 15 and the first conductive semiconductor layer 11 and the second conductive semiconductor layer 12, an ohmic contact is realized approximately. It is thought that.

The first electrode 14 includes an electrode layer (first connection electrode layer) 14 ₁ and an electrode layer (first pad electrode layer) 14 ₂ . Electrode layer 14 ₁ in order to obtain an ohmic contact with the first conductive semiconductor layer 11 is formed on the surface 11a of the first conductivity type semiconductor layer 11. The electrode layer 14 ₂ is formed so as to cover the electrode layer 14 ₁ in order to be bonded to the mounting substrate 2 a via the first bonding portion 31. Electrode layers 14 _1, for example, can be formed by forming a film by vapor deposition or the like Al film on the surface 11a of the first conductivity type semiconductor layer 11. The electrode layer 14 ₂ can be composed of a laminated film of a Ti film and an Au film, for example. The electrode layer 14 ₂ can be formed by, for example, a vapor deposition method or the like. The first electrode 14 is not particularly limited to the layer structure, for example, the first electrode 14 may be composed of whole shape only by the electrode layer 14 _1, and the electrode layer 14 ₁ and the electrode layer 14 ₂ Another electrode layer may be provided between the two.

The second electrode 15 includes an electrode layer (second connection electrode layer) 15 ₁ and an electrode layer (second pad electrode layer) 15 ₂ . Electrode layer 15 ₁ in order to obtain the second conductivity type semiconductor layer 12 and the ohmic contact is formed on the surface 12a of the second conductivity type semiconductor layer 12. Electrode layer 15 _2, for bonding the mounting substrate 2a via the second joint portion 32 is formed so as to cover the electrode layer 15 _1. Electrode layers 15 _1, for example, can be formed by forming a film by vapor deposition or the like laminated film of Ni film and Ag film on the surface 12a of the second conductivity type semiconductor layer 12. Electrode layer 15 _2, for example, can be constituted by a laminated film of a Ti film and an Au film. Electrode layer 15 _2, for example, can be formed by vapor deposition or the like. The second electrode 15 is not particularly limited to the layer structure, for example, the second electrode 15 may be composed of whole shape only by the electrode layer 15 _1, and the electrode layer 15 ₁ and the electrode layer 15 ₂ Another electrode layer may be provided between the two.

Electrode layer 15 ₂ that are formed across the electrode layer 15 ₁ of the surface insulating film 18 surface of the preferred. In the light emitting device B <b> 1, it is preferable that the outer peripheral portion of the second electrode 15 that protrudes away from the second conductive semiconductor layer 12 from the center portion also serves as the protruding structure portion 16. As a result, the light emitting device B1 can increase the bonding area between the LED chip 1a and the mounting substrate 2a to reduce the thermal resistance, and the heat generated in the semiconductor multilayer film 19 of the LED chip 1a can be reduced. It becomes easy to be transmitted to the mounting substrate 2 a side through the protruding structure 16. Therefore, the light emitting device B1 can improve heat dissipation.

  By the way, in the manufacturing method of the light-emitting device B1, the second bonding layer 72 (see FIGS. 4 and 6) has a larger amount of solder than the first bonding layer 71 (see FIGS. 4 and 6), and The thickness change in the second step is large. For this reason, in the manufacturing method of the light emitting device B1, the second bonding layer 72 has a larger amount of pressed down solder than the first bonding layer 71, and the thickness of the second bonding layer 72 varies. Due to this, the solder may protrude from the space 3.

  In the light emitting device B1, the first conductor in the second conductor portion 22 is set so that the interval L2 between the first conductor portion 21 and the second conductor portion 22 is larger than the interval L1 between the first electrode 14 and the second electrode 15. It is preferable that the end on the side of the portion 21 is made to recede from the end on the first electrode 14 side in the second electrode 15. As a result, the light emitting device B1 does not change the shapes of the first electrode 14 and the second electrode 15 of the LED chip 1a and prevents the first electrode 14 and the second electrode 15 from being short-circuited. The protruding solder can be absorbed by the groove 23. Here, in the light emitting device B1, as described above, it is preferable that the thickness of the first conductor portion 21 and the second conductor portion 22 is larger than the distance between the second electrode 15 and the second conductor portion 22. Accordingly, the light emitting device B1 can further suppress the occurrence of a short circuit between the second electrode 15 and the first electrode 14 due to the solder protruding from the space 3.

As described above, the LED chip 1a includes the insulating film 18 formed on the surface 12a of the second conductive type semiconductor layer 12 so as to surround the contact region of the second electrode 15 with the second conductive type semiconductor layer 12. It is preferable. As a first modification, the light emitting device B <b> 1 may be configured such that the insulating film 18 also serves as the protruding structure 16. In this case, provided with an electrode layer 15 _second electrode layer 15 ₁ on the surface only in the second electrode 15, the thickness of the insulating film 18 may be set larger than the thickness of the second electrode 15. Thereby, the 1st modification of light-emitting device B1 can improve the electrical insulation between the 2nd electrode 15 and the 1st electrode 14 more. It becomes possible to simplify the structure of the LED chip 1a and the manufacturing process, and to reduce the cost. In the first modification of the light emitting device B1, the protrusion amount of the protrusion structure portion 16 can be set to a difference between the film thickness of the insulating film 18 and the thickness of the second electrode 15. It is possible to improve the accuracy of the protrusion amount.

  FIG. 8 is a schematic plan view of a light emitting device B2 of a second modification of the light emitting device B1 of the present embodiment. The basic configuration of the light emitting device B2 is substantially the same as that of the light emitting device B1. In the light emitting device B2, the shape of the first electrode 14 and the second electrode 15 in the LED chip 1b (see FIG. 9), the shape of the first conductor portion 21 and the second conductor portion 22 in the mounting substrate 2b (see FIG. 10), and the like. Only the light-emitting device B1 is different. For this reason, detailed description of the light emitting device B2 is omitted. In the light emitting device B2, the same components as those of the light emitting device B1 are denoted by the same reference numerals.

  The LED chip 1b has a smaller chip size than the LED chip 1a (see FIGS. 1 and 3). In the LED chip 1a, the surface 11a of the first conductivity type semiconductor layer 11 is exposed at each of the four corners of the semiconductor multilayer film 19, and the first electrode 14 is formed on each surface 11a. For this reason, the LED chip 1 a includes four first electrodes 14. On the other hand, the LED chip 1b exposes the surface 11a of the first conductive semiconductor layer 11 at one of the four corners of the semiconductor multilayer film 19, and forms the first electrode 14 on the surface 11a. is there. For this reason, in the LED chip 1b, the shape of the second electrode 15 is different from that of the LED chip 1a.

  FIG. 11 is a schematic bottom view of the LED chip 1c in the third modification of the light emitting device B1 of the present embodiment. In the third modification of the light emitting device B1, the shapes of the first electrode 14 and the second electrode 15 in the LED chip 1c are different, and instead of the mounting substrate 2a of the light emitting device B1, the first conductor portion 21 in the mounting substrate 2a and The difference is that a mounting board (not shown) in which the shape or the like of the second conductor portion 22 is changed is provided. For this reason, detailed description of the third modification of the light emitting device B1 is omitted.

  The LED chip 1c has a smaller chip size than the LED chip 1a (see FIGS. 1 and 3) and a larger chip size than the LED chip 1b (see FIGS. 8 and 9). In the LED chip 1 c, the surface 11 a of the first conductor type semiconductor layer 11 is exposed at two of the four corners of the semiconductor multilayer film 19, and the first electrode 14 is formed on each surface 11. Therefore, the LED chip 1c includes two first electrodes 14, and the shape of the second electrode 15 is different from that of the LED chips 1a and 1b.

(Embodiment 2)
Below, light-emitting device B3 of this embodiment is demonstrated based on FIGS. 12 is a schematic schematic cross-sectional view corresponding to the XX cross section of FIG. Note that in the light emitting device B3 of the present embodiment, the same components as those of the light emitting device B1 of the first embodiment are denoted by the same reference numerals, and description thereof will be omitted as appropriate.

  The light emitting device B3 includes a mounting substrate 2d and an LED chip 1d mounted on the mounting substrate 2d. The mounting substrate 2d includes a support 20, and a first conductor portion 21 and a second conductor portion 22 that are supported by the support 20 and to which the LED chip 1d is electrically connected. The LED chip 1d includes a substrate 10, a first conductive semiconductor layer 11 formed on the first surface 10a side of the substrate 10, and a first conductive semiconductor layer 11 formed on the opposite side of the first conductive semiconductor layer 11 from the substrate 10 side. Two-conductivity-type semiconductor layer 12, first electrode 14 formed on exposed surface 11a opposite to substrate 10 side in first-conductivity-type semiconductor layer 11, and on surface 12a of second-conductivity-type semiconductor layer 12 And a second electrode 15 formed on the substrate. The light emitting device B3 protrudes from one of the surface 12a side of the second conductive type semiconductor layer 12 and the surface 22a side of the second conductor portion 22 to the other side and contacts the other side, along the outer periphery of the second electrode 15. The protrusion structure portion 16 is provided. In the light emitting device B3, the first electrode 14 and the first conductor portion 21 are joined by the first joining portion 31 formed by solder, and the second electrode 15 and the second conductor portion 22 are formed by solder. It is joined by the second joining part 32 made. The second joint portion 32 is formed so as to fill the space 3 surrounded by the second electrode 15, the protruding structure portion 16, and the second conductor portion 22. Therefore, in the light emitting device B3, it is possible to make each of the first joint portion 31 and the second joint portion 32 thinner, and each of the first joint portion 31 and the second joint portion 32 includes the first conductor portion 21 and the first conductor portion 21. It becomes possible to join each of the two conductor portions 22 on the surface. As a result, the light emitting device B3 can reduce the thermal resistance between the LED chip 1d and the mounting substrate 2d. Furthermore, since the light emitting device B3 can manage the thickness of the second joint portion 32 by the protruding structure portion 16, it is possible to reduce variation in thermal resistance. In short, the light emitting device B3 can reduce variations in thermal resistance among products. As a result, the light emitting device B3 can improve heat dissipation and reliability.

  The protruding structure portion 16 is formed in a shape along the outer periphery of the second electrode 15 in the second conductor portion 22, and protrudes from the surface 22a side of the second conductor portion 22 more than the periphery of the protruding structure portion 16 in the mounting substrate 2d. It is preferable. As a result, in the light emitting device B3, the protruding structure portion 16 is in contact with the surface 15a of the second electrode 15, and the second joint portion 32 is surrounded by the second electrode 15, the protruding structure portion 16, and the second conductor portion 22. It can be set as the structure formed so that the space 3 might be satisfy | filled.

  In this specification, for convenience of explanation, after describing a method for manufacturing the light emitting device B3, each component of the light emitting device B3 will be described in detail.

  In the method for manufacturing the light emitting device B3 of the present embodiment, first, after preparing the LED chip 1d and the mounting substrate 2d, the first step and the second step are sequentially performed.

  In the first step, as shown in FIGS. 15 and 16, on the surface 21a side of the first conductor portion 21 and the surface 22a side of the second conductor portion 22 of the mounting substrate 2d, the first joint portion 31 and the second joint portion 32 are provided. A first solder layer 41 and a second solder layer 42 are formed as a basis for each. As the solder that is the material of the first solder layer 41 and the second solder layer 42, for example, AuSn can be adopted. The first solder layer 41 and the second solder layer 42 can be formed by, for example, vapor deposition or plating. In the first step, the thicknesses of the first solder layer 41 and the second solder layer 42 are set to the same value. The area of the surface 41a of the first solder layer 41 is set smaller than the area of the surface 14a of the first electrode 14 (see FIG. 14). The area of the surface 42a of the second solder layer 42 is set to be smaller than the area of the surface 15a (see FIG. 14) of the second electrode 15. The thicknesses of the first solder layer 41 and the second solder layer 42 are the protrusion amount H11 (see FIG. 17) of the protrusion structure portion 16 from the surface 22a of the first conductor portion 22, and the second thickness in the thickness direction of the LED chip 1d. It is set to be larger by a predetermined thickness (α) than the sum (H11 + H2) of the step H2 (see FIG. 17) between the electrode 15 and the first electrode 14. That is, the thickness of the first solder layer 41 and the second solder layer 42 is set to H11 + H2 + α. For example, when H11 = 1 μm and H2 = 1 μm, the thicknesses of the first solder layer 41 and the second solder layer 42 may be set to about 3 μm. In this case, α is 1 μm. These numerical values are merely examples, and may be appropriately set based on the structure of the LED chip 1d and the like, and are not particularly limited. The first solder layer 41 and the second solder layer 42 are preferably formed in the center of the region of the mounting substrate 2d that faces the first electrode 14 and the second electrode 15, respectively. The second solder layer 42 is disposed on the surface 22 a of the second conductor portion 22 so as to be positioned away from the protruding structure portion 16 inside the protruding structure portion 16 in plan view.

  In the first step, the first barrier layer 51 and the second barrier layer 52 are formed between the first conductor portion 21 and the second conductor portion 22 and the first solder layer 41 and the second solder layer 42, respectively. preferable.

  In the first step, it is preferable to form the first Au layer 61 and the second Au layer 62 on the first solder layer 41 and the second solder layer 42, respectively. In FIG. 16, the first Au layer 61 and the second Au layer 62 are not shown. Hereinafter, the laminated film of the first barrier layer 51, the first solder layer 41, and the first Au layer 61 will be referred to as a first bonding layer 71, and the second barrier layer 52, the second solder layer 42, and the second Au layer 62 will be described. The laminated film is referred to as a second bonding layer 72. The first bonding layer 71 only needs to include at least the first solder layer 41 and is not limited to a laminated film but may be a single layer film. The second bonding layer 72 only needs to include at least the second solder layer 42 and is not limited to a laminated film but may be a single layer film.

  In the second step, the first step and the second step are sequentially performed. In the second step, a die bonding apparatus (not shown) is used. The die bonding apparatus includes, for example, a suction holder that can hold the LED chip 1d by suction, a stage on which the mounting board 2d is placed, a first heater that is provided on the stage and can heat the mounting board 2d, and a suction holder. Or the thing of the structure provided with the 2nd heater with which either of the holder holding an adsorption | suction holder was equipped is preferable. Examples of the suction holding tool include a collet.

  In the first step, as shown in FIG. 17, the LED chip 1d and the mounting substrate 2d are opposed to each other.

  In the first step, the first electrode 14 and the second electrode 15 of the LED chip 1d sucked and held by the suction holder are opposed to the first conductor portion 21 and the second conductor portion 22 of the mounting substrate 2d.

  In the second step, the first electrode 14 and the second electrode 15 of the LED chip 1d and the first conductor portion 21 and the second conductor portion 22 of the mounting substrate 2d are joined by the first joint portion 31 formed by solder and the solder. Joining is performed by the formed second joining portion 32.

  In the second step described above, the first electrode 14 and the second electrode 15 of the LED chip 1d are superposed so that the first bonding layer 71 and the second bonding layer 72 on the mounting substrate 2d are in contact with each other. The first solder layer 41 and the second solder layer 42 are melted while performing appropriate heating and pressing. In the second step, after the first solder layer 41 and the second solder layer 42 are melted as described above, the protrusion structure 16 is pressed from the LED chip 1d side so as to be in contact with the second electrode 15, The molten solder is pushed down and spread laterally to fill the space 3 with solder, and then cooled and solidified.

  By the way, the volume of the second bonding layer 72 formed in the first step is preferably set to be equal to the volume of the space 3 so that the solder forming the second bonding portion 32 does not come out of the space 3. .

  In the method of manufacturing the light emitting device B3, the molten solder is used so that the protruding structure portion 16 of the mounting substrate 2d is in contact with the surface 15a of the second electrode 15 in a state where each of the first solder layer 41 and the second solder layer 42 is melted. The LED chip 1d and the mounting substrate 2d are joined by pressing down. Therefore, in the method for manufacturing the light emitting device B3, it is possible to suppress the first electrode 14 and the first conductor portion 21 from being unjoined.

  In the manufacturing method of the light emitting device B3, the protruding structure portion 16 is in contact with the second electrode 15, the first electrode 14 and the first conductor portion 21 are joined by the first joining portion 31 formed of solder, and the second electrode 15 and the 2nd conductor part 22 are joined by the 2nd junction part 32 formed of the solder. Thereby, in the method for manufacturing the light emitting device B3, the second bonding portion 32 is formed so as to fill the space 3 surrounded by the second electrode 15, the protruding structure portion 16, and the second conductor portion 22, and It becomes possible to do. In the manufacturing method of the light emitting device B3, when the molten solder of the second bonding layer 72 is pressed down and spread in the lateral direction, the protruding structure 16 causes the molten solder to flow along the surface of the LED chip 1d. Therefore, it is possible to suppress the occurrence of a short circuit due to the solder between the first electrode 14 and the second electrode 15. Moreover, in the manufacturing method of the light emitting device B3, the light emitting device B3 that can reduce the thermal resistance between the LED chip 1d and the mounting substrate 2d and can reduce the variation in the thermal resistance is manufactured. Is possible.

  In the manufacturing method of the light emitting device B3, when the area of the second electrode 15 is larger than the area of the first electrode 14, there is a concern that an unstable spread is more likely to occur in the second joint portion 32 than in the first joint portion 31. There is. For this reason, in the manufacturing method of light-emitting device B3, it is preferable to form the 2nd joining layer 72 in a predetermined pattern. The pattern of the second bonding layer 72 may be appropriately changed depending on the planar shape of the second electrode 15, but for example, as shown in FIGS. 16 and 18, it is preferable to have a radial shape that makes it difficult for air bubbles to be taken in. . Thereby, in the manufacturing method of the light emitting device B3, it is possible to stabilize the spread when the solder melted in the second step is pushed down and spread, and the generation of voids in the second joint portion 32 can be suppressed. It becomes possible.

  By the way, in the manufacturing method of the light emitting device B3, it is preferable to apply a load so that the entire front end surface of the protruding structure 16 is in contact with the LED chip 1d. However, in the manufacturing method of the light emitting device B3, due to the difference between the flatness of the tip surface of the protrusion structure 16 and the flatness of the LED chip 1d, the entire tip surface of the protrusion structure 16 is covered with the LED chip 1d. It can be difficult to make contact with the side. In the example of FIG. 17, there is a part of the second electrode 15 and a part of the insulating film 18 in the vertical projection region of the protrusion structure 16 on the LED chip 1 d side. The difference in flatness on the LED chip 1d side is likely to occur. In this case, a part of the front end surface of the protrusion structure portion 16 is in contact with the surface 15a of the second electrode 15, and the remaining portion of the front end surface of the protrusion structure portion 16 and the LED chip 1d are immersed during manufacture. In some cases, a thin solder layer may be left that is made of hardened solder. In short, the light emitting device B3 may have a configuration in which the protruding structure 16 partially contacts the surface 15a of the second electrode 15 as long as the parallelism of the LED chip 1d with respect to the mounting substrate 2d is in a desired range. In the manufacturing method of the light emitting device B3, if the load applied in the second step is increased, the difference between the flatness of the tip surface of the protrusion structure 16 and the flatness on the LED chip 1d side can be reduced. The contact area between the portion 16 and the second electrode 15 can be increased. In the manufacturing method of the light emitting device B3, when the protruding structure 16 is made of, for example, metal, the protruding structure 16 can be deformed so as to be compressed by increasing the load applied in the second step. Become. Thereby, in the manufacturing method of light-emitting device B3, it becomes possible to enlarge the contact area of the protrusion structure part 16 and the 2nd electrode 15. FIG.

  In the method for manufacturing the light emitting device B3, as described above, it is preferable to form the first Au layer 61 and the second Au layer 62 on the first solder layer 41 and the second solder layer 42, respectively, in the first step. Thereby, in the manufacturing method of light-emitting device B3, it becomes possible to suppress that the Sn of the 1st solder layer 41 and the 2nd solder layer 42 oxidizes before the 2nd process, and LED chip 1d, mounting board 2d, and It becomes possible to improve the bondability.

  Each component of the light emitting device B3 will be described below.

  In the light emitting device B1 according to Embodiment 1 shown in FIG. 1, the protruding structure 16 is formed on the LED chip 1a. On the other hand, the light emitting device B3 of the present embodiment is different in that the protruding structure portion 16 is formed on the mounting substrate 2d.

  The mounting board 2d is substantially the same as the mounting board 2a in the light-emitting device B1 of Embodiment 1, and is different in that the mounting board 2d is provided. In short, the mounting substrate 2 d includes the support 20, the first conductor portion 21, the second conductor portion 22, and the protruding structure portion 16.

  In the mounting substrate 2d, the first conductor portion 21 and the second conductor portion 22 are formed so that the first conductor portion 21 and the second conductor portion 22 are spatially separated. As a result, the mounting substrate 2 d has a groove 23 formed between the first conductor portion 21 and the second conductor portion 22. The inner surface of the groove 23 is constituted by a part of the first surface 20 a of the support 20 and the opposing surfaces of the first conductor portion 21 and the second conductor portion 22. In the mounting substrate 2 d, the first conductor portion 21 and the second conductor portion 22 are formed on the first surface 20 a of the support body 20 with the same thickness. Thereby, the mounting substrate 2d is configured such that the surface 21a of the first conductor portion 21 and the surface 22a of the second conductor portion 22 are aligned on one plane.

  In the mounting substrate 2 d, the protruding structure portion 16 is formed in a shape along the outer periphery of the second electrode 15 in the second conductor portion 22, and protrudes on the surface 22 a side of the second conductor portion 22. In addition, the mounting substrate 2 d includes a protruding structure portion 17 that surrounds the first joint portion 31. The protruding structure portion 17 protrudes from the surface 21 a of the first conductor portion 21.

  The LED chip 1d has substantially the same configuration as the LED chip 1a (see FIGS. 1 and 3), and is different from the LED chip 1a in that the protruding structures 16 and 17 are not provided. The LED chip 1d has the same chip size as the LED chip 1a, but is not limited to this.

  In the LED chip 1 d, the second electrode 15 is preferably larger than the first electrode 14. And it is preferable that the protrusion structure part 16 is formed in the shape along the perimeter of the outer periphery of the 2nd electrode 15 in the 2nd conductor part 22. As shown in FIG. As a result, the light emitting device B3 can further suppress the occurrence of a short circuit between the second electrode 15 and the first electrode 14 due to the solder forming the second joint portion 32 during manufacturing. In addition, when the LED chip 1a is mounted on the mounting substrate 2a, the light emitting device B3 can improve the reproducibility of the shape of the second joint portion 32 and can reduce variations in thermal resistance.

  The protrusion structure portion 16 is preferably formed of the same material as that of the second conductor portion 22 that is joined to the second joint portion 32 and joined to the second joint portion 32. Thereby, the light emitting device B3 can improve heat dissipation.

Projecting structure 16, for example, it is made of the same material as the Au film 22 ₃ in the second conductor portion 22. In short, the protruding structure 16 is made of Au. The protruding structure 16 can be formed using a vapor deposition method, a sputtering method, a plating method, or the like. In the light emitting device B3, when the material of the protruding structure portion 16 is the same material as the Au film 22 ₃ in the second conductor portion 22, the structure in which the Au film 22 ₃ of the second conductor portion 22 and the protruding structure portion 16 are combined. For example, if it is formed by a vapor deposition method, the vapor deposition may be performed in two steps.

  The distance between the second electrode 15 and the second conductor portion 22 can be determined by the protruding amount H11 of the protruding structure portion 16. In other words, the distance between the second electrode 15 and the second conductor portion 22 is substantially the same as the protruding amount H11 of the protruding structure portion 16.

  The light emitting device B3 can reduce the flow velocity of the protruding solder at the groove 23 even when the solder protrudes from the space 3 at the time of manufacture. In the light emitting device B3, the side surface of the protruding structure 16 and the side surface of the second conductor portion 22 function as a solder guiding portion that guides the protruding solder toward the first surface 20a side of the support 20 at the time of manufacture. It becomes possible. Accordingly, the light emitting device B3 can suppress the occurrence of a short circuit between the second electrode 15 and the first electrode 14 due to the solder protruding from the space 3.

  Similar to the LED chip 1a (see FIG. 1), the LED chip 1d is formed on the surface 12a of the second conductive type semiconductor layer 12 so as to surround the contact region of the second electrode 15 with the second conductive type semiconductor layer 12. The insulating film 18 is preferably provided.

  In the LED chip 1 d, the insulating film 18 is formed across the mesa structure surface 19 a (the surface 12 a of the second conductive semiconductor layer 12), the side surface 19 c, and the surface 11 a of the first conductive semiconductor layer 11. Is preferred. The portion of the insulating film 18 formed on the surface 11a of the first conductive type semiconductor layer 11 is formed in a pattern surrounding the contact region of the first electrode 14 with the first conductive type semiconductor layer 11. Is preferred.

  By the way, in the manufacturing method of the light emitting device B3 described above, the second bonding layer 72 (see FIGS. 15 and 17) has a larger amount of solder than the first bonding layer 71 (see FIGS. 15 and 17), and The thickness change in the second step is large. For this reason, in the manufacturing method of the light emitting device B3, the second bonding layer 72 has a larger amount of pressed down solder than the first bonding layer 71, and the thickness of the second bonding layer 72 varies. Due to this, the solder may protrude from the space 3.

  Here, in the light emitting device B <b> 3, it is preferable that the thickness of the first conductor portion 21 and the second conductor portion 22 is larger than the distance between the second electrode 15 and the second conductor portion 22. Thereby, the light emitting device B3 can absorb the solder protruding from the space 3 by the groove 23, and further suppress the occurrence of a short circuit between the second electrode 15 and the first electrode 14 due to the solder protruding from the space 3. It becomes possible to do.

  FIG. 19 is a main part schematic plan view showing a light emitting device B4 of a first modification of the light emitting device B3 of the present embodiment. The basic configuration of the light emitting device B4 is substantially the same as that of the light emitting device B3. In the light emitting device B4, the shape of the first electrode 14 and the second electrode 15 in the LED chip 1e (see FIG. 20), the shape of the first conductor portion 21 and the second conductor portion 22 in the mounting substrate 2e (see FIG. 21), and the like. Only the light emitting device B3 is different. For this reason, detailed description of the light emitting device B4 is omitted. In addition, in the light-emitting device B4, the same code | symbol is attached | subjected to the component similar to light-emitting device B3.

  The LED chip 1e has a smaller chip size than the LED chip 1d (see FIGS. 12 and 14). In the LED chip 1d, the surface 11a of the first conductive type semiconductor layer 11 is exposed at each of the four corners of the semiconductor multilayer film 19, and the first electrode 14 is formed on each surface 11a. For this reason, the LED chip 1 d includes four first electrodes 14. On the other hand, the LED chip 1e has the surface 11a of the first conductive semiconductor layer 11 exposed at one of the four corners of the semiconductor multilayer film 19, and the first electrode 14 is formed on the surface 11a. is there. For this reason, in the LED chip 1e, the shape of the second electrode 15 is different from that of the LED chip 1d.

  FIG. 22 is a main part schematic plan view showing a light emitting device B5 of a second modification of the light emitting device B3 of the present embodiment. The basic configuration of the light emitting device B5 is substantially the same as that of the light emitting device B3. In the light emitting device B5, the shape of the first electrode 14 and the second electrode 15 in the LED chip 1f (see FIG. 23) is the same as the shape of the first conductor portion 21 and the second conductor portion 22 in the mounting substrate 2f (see FIG. 22). However, this is only different from the light emitting device B3. For this reason, detailed description of the light emitting device B5 is omitted. In addition, in the light-emitting device B5, the same code | symbol is attached | subjected to the component similar to light-emitting device B3.

  The LED chip 1f has a smaller chip size than the LED chip 1d (see FIGS. 12 and 14) and a larger chip size than the LED chip 1e (see FIGS. 22 and 23). In the LED chip 1 f, the surface 11 a of the first conductor type semiconductor layer 11 is exposed at two of the four corners of the semiconductor multilayer film 19, and the first electrode 14 is formed on each surface 11. Therefore, the LED chip 1f includes two first electrodes 14, and the shape of the second electrode 15 is different from that of the LED chips 1d and 1e.

  FIG. 24 is a main part schematic cross-sectional view showing a light emitting device B6 of a third modification of the light emitting device B3 of the present embodiment. The basic configuration of the light emitting device B6 is substantially the same as that of the light emitting device B3. The light emitting device B6 is different from the light emitting device B3 only in the shape of the protruding structure 17 on the mounting substrate 2g. For this reason, detailed description of the light emitting device B6 is omitted. In addition, in the light-emitting device B6, the same code | symbol is attached | subjected to the component similar to light-emitting device B3.

  In the light emitting device B6, the protruding amount of the protruding structure 17 is set so that the tip surface of the protruding structure 17 is in contact with the LED chip 1d side. As a result, the light emitting device B6 can limit the range in which the first bonding portion 31 spreads, and can further suppress the occurrence of a short circuit between the first electrode 14 and the second electrode 15. .

  FIG. 25 is a main part schematic cross-sectional view showing a light emitting device B7 of a fourth modification of the light emitting device B3 of the present embodiment. The basic configuration of the light emitting device B7 is substantially the same as that of the light emitting device B3. The light emitting device B7 is different from the light emitting device B3 only in that the mounting substrate 2h does not include the protruding structure portion 17 (see FIG. 12). For this reason, detailed description of the light emitting device B7 is omitted. In addition, in the light-emitting device B7, the same code | symbol is attached | subjected to the component similar to light-emitting device B3.

  Since the light emitting device B7 does not include the protruding structure 17 of the light emitting device B3, the manufacturing process can be simplified as compared with the light emitting device B.

  FIG. 26 is a main part schematic cross-sectional view showing a light emitting device B8 of a fifth modification of the light emitting device B3 of the present embodiment. The basic configuration of the light emitting device B8 is substantially the same as that of the light emitting device B3. The light emitting device B8 is different from the light emitting device B3 only in the material of the protruding structures 16 and 17 on the mounting substrate 2i. Therefore, detailed description of the light emitting device B8 is omitted. In addition, in the light-emitting device B8, the same code | symbol is attached | subjected to the component similar to light-emitting device B3.

  The protruding structure portion 16 in the light emitting device B8 has lower solder wettability than the second conductor portion 22, and is not joined to the second joint portion 32. Thereby, the light emitting device B8 can further suppress the solder forming the second joint portion 32 from protruding from the space 3, and the occurrence of a short circuit between the first electrode 14 and the second electrode 15 can be prevented. It becomes possible to suppress more.

The solder wettability of the second conductor part 22 means the solder wettability of the part of the second conductor part 22 that is joined to the second joint part 32. Therefore, the solderability of the second conductor portion 22, a solder wettability of the Au film 22 ₃ in the second conductor portion 22.

  The solder wettability of the protruding structure 16 means the solder wettability of the protruding structure 16 on the front end side and the side surface side.

The protruding structure 16 can be constituted by, for example, an Al film and an aluminum oxide film formed on the surface of the Al film. Aluminum oxide film, as compared with the Au film 22 _3, low solder wettability, and has a property of repelling the solder. Moreover, the protrusion structure part 16 can be comprised with Ni film | membrane and the nickel oxide film | membrane formed in the surface of this Ni film | membrane, for example. Nickel oxide film, as compared with the Au film 22 _3, low solder wettability, and has a property of repelling the solder. Moreover, the protrusion structure part 16 can also be comprised by the aluminum oxide film, the nickel oxide film, the silicon oxide film, etc., for example. Silicon oxide film, as compared with the Au film 22 _3, low solder wettability, and has a property of repelling the solder.

  FIG. 27 is a main part schematic cross-sectional view showing a light emitting device B9 of a sixth modification of the light emitting device B3 of the present embodiment. The basic configuration of the light emitting device B9 is substantially the same as that of the light emitting device B3. The light emitting device B9 is different only in that the LED chip 1g includes the protruding structure 16. For this reason, detailed description of the light emitting device B9 is omitted. In the light emitting device B9, the same components as those of the light emitting device B3 are denoted by the same reference numerals.

  The light emitting device B9 protrudes from both the surface 12a side of the second conductive type semiconductor layer 12 and the surface 22a side of the second conductor portion 22 to the other side, contacts the other side, and extends along the outer periphery of the second electrode 15. The protrusion structure parts 16 and 16 located are provided. In the light emitting device B, the front end surfaces of the protruding structure portion 16 (16b) formed on the mounting substrate 2d and the protruding structure portion 16 (16a) formed on the LED chip 1g are in contact with each other. The protrusion structure portion 16a in the LED chip 1g has the same structure as the LED chip 1a (see FIG. 1).

  In the light emitting device B9, the first electrode 14 and the first conductor portion 21 are joined by the first joint portion 31 formed of solder, and the second electrode 15 and the second conductor portion 22 are formed of solder. Joined by the second joining portion 32. The second joint portion 32 is formed so as to fill the space 3 surrounded by the second electrode 15, the protruding structure portions 16 a and 16 b, and the second conductor portion 22. As with the light emitting device B3, the light emitting device B9 can reduce the thermal resistance between the LED chip 1g and the mounting substrate 2d.

  When manufacturing the light emitting device B9, as shown in FIG. 28, the LED chip 1g and the mounting substrate 2d are opposed to each other, and then the first electrode 14 and the second electrode 15 of the LED chip 1g and the first conductor portion of the mounting substrate 2d. 21 and the second conductor portion 22 are joined by the first joint portion 31 and the second joint portion 32.

  The thicknesses of the first solder layer 41 and the second solder layer 42 are such that the protrusion amount H1 of the protrusion structure portion 16a from the surface 15a of the first electrode 15 and the protrusion structure portion 16b from the surface 22a of the first conductor portion 22 are. It is set to be larger by a predetermined thickness (α) than the sum (H1 + H11 + H2) of the protrusion amount H11 and the step H2 between the second electrode 15 and the first electrode 14 in the thickness direction of the LED chip 1d. That is, the thickness of the first solder layer 41 and the second solder layer 42 is set to H1 + H11 + H2 + α. For example, when H1 = 1 μm, H11 = 1 μm, and H2 = 1 μm, the thicknesses of the first solder layer 41 and the second solder layer 42 may be set to about 4 μm. In this case, α is 1 μm. These numerical values are examples and are not particularly limited.

  Each figure described in the above-described first and second embodiments is schematic, and the ratio of the size and thickness of each component does not necessarily reflect the actual dimensional ratio. . In addition, the materials, numerical values, and the like described in the first and second embodiments are merely preferable examples and are not limited thereto. Furthermore, the present invention can be appropriately modified in configuration without departing from the scope of its technical idea.

  In this specification, the following invention is described as is clear from the description of the first and second embodiments.

(1) A mounting board and an LED chip mounted on the mounting board,
The mounting substrate includes a support, and a first conductor part and a second conductor part that are supported by the support and to which the LED chip is electrically connected,
The LED chip includes a substrate, a first conductivity type semiconductor layer formed on the first surface side of the substrate, and a second conductivity type formed on the opposite side of the first conductivity type semiconductor layer from the substrate side. A semiconductor layer; a first electrode formed on an exposed surface of the first conductive semiconductor layer opposite to the substrate; and a second electrode formed on the surface of the second conductive semiconductor layer. And comprising
A protrusion that protrudes from at least one of the surface side of the second conductivity type semiconductor layer and the surface side of the second conductor portion to the other side and is in contact with the other side and is positioned along the outer periphery of the second electrode With a structure,
The first electrode and the first conductor portion are joined by a first joint portion formed of solder,
The second electrode and the second conductor portion are joined by a second joint portion formed of solder,
The light emitting device, wherein the second joint portion is formed to fill a space surrounded by the second electrode, the protruding structure portion, and the second conductor portion.

  (2) The protrusion structure portion is formed along an outer periphery of the second electrode in the LED chip, and on the surface side of the second conductivity type semiconductor layer, from the periphery of the protrusion structure portion in the LED chip. The light emitting device according to (1), wherein the light emitting device also protrudes.

  (3) The LED chip is characterized in that the second electrode is larger than the first electrode, and the protruding structure is formed over the entire outer periphery of the second electrode (2). ) The light emitting device described.

  (4) In the mounting board, the thickness of the first conductor part and the second conductor part is larger than the distance between the second electrode and the second conductor part (2) or ( 3) The light emitting device according to the above.

  (5) The LED chip includes an insulating film formed on the surface of the second conductivity type semiconductor layer so as to surround a contact region of the second electrode with the second conductivity type semiconductor layer. Two electrodes are formed across the surface of the second conductive type semiconductor layer and the surface of the insulating film, and the outer periphery protrudes in a direction away from the second conductive type semiconductor layer from the center of the second electrode The light emitting device according to any one of (2) to (4), wherein the portion also serves as the protruding structure portion.

  (6) The LED chip includes an insulating film formed on the surface of the second conductive type semiconductor layer so as to surround a contact region of the second electrode with the second conductive type semiconductor layer, and The light emitting device according to any one of (2) to (4), wherein the film also serves as the protruding structure portion.

  (7) The protrusion structure portion is formed in a shape along the outer periphery of the second electrode in the second conductor portion, and around the protrusion structure portion in the mounting substrate on the surface side of the second conductor portion. The light emitting device according to (1), wherein the light emitting device protrudes further.

  (8) In the LED chip, the second electrode is larger than the first electrode, and the protruding structure portion is formed in a shape along the entire outer periphery of the second electrode in the second conductor portion. (7) The light-emitting device according to (7).

  (9) The protruding structure portion is formed of the same material as the portion to be joined to the second joint portion in the second conductor portion, and is joined to the second joint portion (7) Or the light-emitting device of (8) description.

  (10) The light emitting device according to (7) or (8), wherein the protrusion structure portion has lower solder wettability than the second conductor portion and is not joined to the second joint portion.

  (11) The light emitting device according to any one of (1) to (10), wherein the solder forming the first joint and the solder forming the second joint are AuSn.

  (12) The first conductor portion side of the second conductor portion is arranged so that a gap between the first conductor portion and the second conductor portion is wider than a gap between the first electrode and the second electrode. The light emitting device according to any one of (1) to (11), wherein an end of the second electrode is set back relative to an end of the second electrode on the first electrode side.

1a, 1b, 1c, 1d, 1e, 1f, 1g LED chip 2a, 2b, 2d, 2e, 2f, 2g, 2h, 2i Mounting substrate 3 Space 10 Substrate 10a First surface 11 First conductivity type semiconductor layer 11a Surface 12 Second Conductive Semiconductor Layer 12a Surface 14 First Electrode 15 Second Electrode 16 Protrusion Structure 18 Insulating Film 20 Support 21 First Conductor 21a Surface 22 Second Conductor 22a Surface 31 First Junction 32 Second Junction B1, B2, B3, B4, B5, B6, B7, B8, B9 Light emitting device

The light emitting device of the present invention, a mounting substrate, and a LED chip mounted on the mounting substrate, before Symbol mounting substrate, a support, wherein the LED chip is supported by the support member is electrically connected A first conductor portion and a second conductor portion, wherein the LED chip includes a substrate, a first conductivity type semiconductor layer formed on a first surface side of the substrate, and a first conductivity type semiconductor layer. A second conductive semiconductor layer formed on a side opposite to the substrate side; a first electrode formed on an exposed surface of the first conductive type semiconductor layer opposite to the substrate side; A second electrode formed on the surface of the two-conductivity-type semiconductor layer, from at least one of the surface side of the second-conductivity-type semiconductor layer and the surface side of the second conductor portion to the other side Protrudes and touches the other side and is located along the outer periphery of the second electrode. Providing a projecting structure portion, the first electrode and the first conductor portion are joined by a first joint portion formed of solder, and the second electrode and the second conductor portion are formed of solder Bonded by a second bonding portion, the second bonding portion is formed so as to fill a space surrounded by the second electrode, the protruding structure portion, and the second conductor portion, and the protruding structure portion is The LED chip is formed along the outer periphery of the second electrode of the LED chip, and protrudes from the surface of the second conductive semiconductor layer from the periphery of the protruding structure portion of the LED chip, and the LED chip , the greater than the second electrode and the first electrode, the protruding structure is characterized that you have been formed over the entire circumference of the outer periphery of the second electrode.

In this light emitting device, the pre-Symbol second joint includes a barrier layer formed on the surface of the second conductor portion in addition to the portion formed by the solder, the barrier layer, the diffusion barrier The second bonding portion has the barrier layer formed away from the protruding structure portion inside the protruding structure portion, and a portion formed by solder is formed of the second conductor portion. The surface is preferably formed so as to cover a portion of the surface where the barrier layer is not formed and the surface and side surfaces of the barrier layer .

In this light emitting device, before Symbol said surface of said second conductor portion surrounded by protruding structure section, the area in contact with the portion formed by soldering, and Okiiko than the area in contact with the barrier layer Is preferred.

Another light-emitting device of the present invention includes a mounting board and an LED chip mounted on the mounting board. The mounting board is supported by the support and the LED chip is electrically connected to the support. The LED chip includes a substrate, a first conductive semiconductor layer formed on a first surface side of the substrate, and the first conductive semiconductor layer. A second conductive type semiconductor layer formed on the opposite side of the substrate side of the first conductive type semiconductor layer, a first electrode formed on an exposed surface of the first conductive type semiconductor layer opposite to the substrate side, A second electrode formed on the surface of the second conductivity type semiconductor layer, and the other side from at least one of the surface side of the second conductivity type semiconductor layer and the surface side of the second conductor portion Protrudes toward the other side and extends along the outer periphery of the second electrode. The first electrode and the first conductor portion are joined by a first joint portion formed of solder, and the second electrode and the second conductor portion are formed of solder. joined by the second joining portion, the second junction, the second electrode and are formed so as to satisfy the enclosed space between the protruding structure portion and the second conductor part, prior SL projection structure The part is formed in a shape along the outer periphery of the second electrode in the second conductor part, and protrudes from the surface side of the second conductor part beyond the periphery of the protruding structure part in the mounting substrate. And features.

The chip size of the LED chip 1a is not particularly limited. As the LED chip 1a, for example, the chip size is 0.4 mm □ (0.4 mm × 0.4 mm), 0.6 mm □ (0.6 mm × 0.6 mm), or 0.8 mm □ (0.8 mm × 0. 8 mm) or 1 mm □ (1 mm × 1 mm) can be used. Further, the planar shape of the LED chip 1a is not limited to a square shape, and may be a rectangular shape, for example. When the planar shape of the LED chip 1a is rectangular, the LED chip 1a having a chip size of 0.5 mm × 0.24 mm, for example, can be used.

The LED chip 1b has a smaller chip size than the LED chip 1a (see FIGS. 1 and 3). In the LED chip 1a, the surface 11a of the first conductivity type semiconductor layer 11 is exposed at each of the four corners of the semiconductor multilayer film 19, and the first electrode 14 is formed on each surface 11a. For this reason, the LED chip 1 a includes four first electrodes 14. In contrast, LED chips 1b exposes the surface 11a of the first conductive semiconductor layer 11 at one place of the four corners of the semiconductor multilayer film 19, the first electrode 14 is formed on the surface 11a It is. For this reason, in the LED chip 1b, the shape of the second electrode 15 is different from that of the LED chip 1a.

The LED chip 1c has a smaller chip size than the LED chip 1a (see FIGS. 1 and 3) and a larger chip size than the LED chip 1b (see FIGS. 8 and 9). LED chip 1c exposes the surface 11a of the first conductive semiconductor layer 11 in two places of the four corners of the semiconductor multilayer film 19, is formed a first electrode 14 on the surface 11 a. Therefore, the LED chip 1c includes two first electrodes 14, and the shape of the second electrode 15 is different from that of the LED chips 1a and 1b.

In the first step, as shown in FIGS. 15 and 16, on the surface 21a side of the first conductor portion 21 and the surface 22a side of the second conductor portion 22 of the mounting substrate 2d, the first joint portion 31 and the second joint portion 32 are provided. A first solder layer 41 and a second solder layer 42 are formed as a basis for each. As the solder that is the material of the first solder layer 41 and the second solder layer 42, for example, AuSn can be adopted. The first solder layer 41 and the second solder layer 42 can be formed by, for example, vapor deposition or plating. In the first step, the thicknesses of the first solder layer 41 and the second solder layer 42 are set to the same value. The area of the surface 41a of the first solder layer 41 is set smaller than the area of the surface 14a of the first electrode 14 (see FIG. 14). The area of the surface 42a of the second solder layer 42 is set to be smaller than the area of the surface 15a (see FIG. 14) of the second electrode 15. The thicknesses of the first solder layer 41 and the second solder layer 42 are the protrusion amount H11 (see FIG. 17) of the protrusion structure portion 16 from the surface 22a of the second conductor portion 22, and the second thickness in the thickness direction of the LED chip 1d. It is set to be larger by a predetermined thickness (α) than the sum (H11 + H2) of the step H2 (see FIG. 17) between the electrode 15 and the first electrode 14. That is, the thickness of the first solder layer 41 and the second solder layer 42 is set to H11 + H2 + α. For example, when H11 = 1 μm and H2 = 1 μm, the thicknesses of the first solder layer 41 and the second solder layer 42 may be set to about 3 μm. In this case, α is 1 μm. These numerical values are merely examples, and may be appropriately set based on the structure of the LED chip 1d and the like, and are not particularly limited. The first solder layer 41 and the second solder layer 42 are preferably formed in the center of the region of the mounting substrate 2d that faces the first electrode 14 and the second electrode 15, respectively. The second solder layer 42 is disposed on the surface 22 a of the second conductor portion 22 so as to be positioned away from the protruding structure portion 16 inside the protruding structure portion 16 in plan view.

The LED chip 1e has a smaller chip size than the LED chip 1d (see FIGS. 12 and 14). In the LED chip 1d, the surface 11a of the first conductive type semiconductor layer 11 is exposed at each of the four corners of the semiconductor multilayer film 19, and the first electrode 14 is formed on each surface 11a. For this reason, the LED chip 1 d includes four first electrodes 14. In contrast, LED chips 1e exposes the surface 11a of the first conductive semiconductor layer 11 at one place of the four corners of the semiconductor multilayer film 19, the first electrode 14 is formed on the surface 11a It is. For this reason, in the LED chip 1e, the shape of the second electrode 15 is different from that of the LED chip 1d.

The LED chip 1f has a smaller chip size than the LED chip 1d (see FIGS. 12 and 14) and a larger chip size than the LED chip 1e (see FIGS. 22 and 23). LED chip 1f exposes the surface 11a of the first conductive semiconductor layer 11 in two places of the four corners of the semiconductor multilayer film 19, is formed a first electrode 14 on the surface 11 a. Therefore, the LED chip 1f includes two first electrodes 14, and the shape of the second electrode 15 is different from that of the LED chips 1d and 1e.

The thicknesses of the first solder layer 41 and the second solder layer 42 are such that the protrusion amount H1 of the protrusion structure portion 16a from the surface 15a of the second electrode 15 and the protrusion structure portion 16b from the surface 22a of the second conductor portion 22 are. It is set to be larger by a predetermined thickness (α) than the sum (H1 + H11 + H2) of the protrusion amount H11 and the step H2 between the second electrode 15 and the first electrode 14 in the thickness direction of the LED chip 1d. That is, the thickness of the first solder layer 41 and the second solder layer 42 is set to H1 + H11 + H2 + α. For example, when H1 = 1 μm, H11 = 1 μm, and H2 = 1 μm, the thicknesses of the first solder layer 41 and the second solder layer 42 may be set to about 4 μm. In this case, α is 1 μm. These numerical values are examples and are not particularly limited.

Claims (12)

A mounting board, and an LED chip mounted on the mounting board,
The mounting substrate includes a support, and a first conductor part and a second conductor part that are supported by the support and to which the LED chip is electrically connected,
The LED chip includes a substrate, a first conductivity type semiconductor layer formed on the first surface side of the substrate, and a second conductivity type formed on the opposite side of the first conductivity type semiconductor layer from the substrate side. A semiconductor layer; a first electrode formed on an exposed surface of the first conductive semiconductor layer opposite to the substrate; and a second electrode formed on the surface of the second conductive semiconductor layer. And comprising
A protrusion that protrudes from at least one of the surface side of the second conductivity type semiconductor layer and the surface side of the second conductor portion to the other side and is in contact with the other side and is positioned along the outer periphery of the second electrode With a structure,
The first electrode and the first conductor portion are joined by a first joint portion formed of solder,
The second electrode and the second conductor portion are joined by a second joint portion formed of solder,
The light emitting device, wherein the second joint portion is formed to fill a space surrounded by the second electrode, the protruding structure portion, and the second conductor portion.   The protrusion structure portion is formed along an outer periphery of the second electrode in the LED chip, and protrudes from the surface side of the second conductivity type semiconductor layer beyond the periphery of the protrusion structure portion in the LED chip. The light-emitting device according to claim 1.   3. The LED chip according to claim 2, wherein the second electrode is larger than the first electrode, and the protruding structure is formed over the entire circumference of the second electrode. Light emitting device.   4. The light emitting device according to claim 2, wherein the mounting board has a thickness of the first conductor portion and the second conductor portion larger than a distance between the second electrode and the second conductor portion. apparatus.   The LED chip includes an insulating film formed on the surface of the second conductive type semiconductor layer so as to surround a contact region of the second electrode with the second conductive type semiconductor layer, and the second electrode includes An outer peripheral portion that is formed across the surface of the second conductive type semiconductor layer and the surface of the insulating film and protrudes in a direction away from the second conductive type semiconductor layer from the central portion of the second electrode, The light-emitting device according to claim 2, wherein the light-emitting device also serves as the protruding structure portion.   The LED chip includes an insulating film formed on the surface of the second conductive semiconductor layer so as to surround a contact region of the second electrode with the second conductive semiconductor layer, and the insulating film includes: The light-emitting device according to claim 2, wherein the light-emitting device also serves as the protruding structure portion.   The protrusion structure portion is formed in a shape along the outer periphery of the second electrode in the second conductor portion, and protrudes from the surface side of the second conductor portion from the periphery of the protrusion structure portion in the mounting substrate. The light-emitting device according to claim 1.   In the LED chip, the second electrode is larger than the first electrode, and the protruding structure portion is formed in a shape along the entire outer periphery of the second electrode in the second conductor portion. The light-emitting device according to claim 7.   9. The projecting structure portion is formed of the same material as a portion to be joined to the second joint portion in the second conductor portion, and is joined to the second joint portion. Light-emitting device.   9. The light emitting device according to claim 7, wherein the protruding structure part has lower solder wettability than the second conductor part and is not joined to the second joint part.   11. The light emitting device according to claim 1, wherein the solder forming the first joint and the solder forming the second joint are AuSn.   The end of the second conductor portion on the first conductor portion side is set so that the interval between the first conductor portion and the second conductor portion is wider than the interval between the first electrode and the second electrode. The light emitting device according to any one of claims 1 to 11, wherein the light emitting device is retracted from an end of the second electrode on the first electrode side.

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