JP2007305773A - Light-emitting device, and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light emitting device capable of suppressing the loss of light due to optical guide wave in a wavelength conversion member while not generating leak light whose wavelength is not converted. <P>SOLUTION: The light emitting device is provided with a semiconductor light emitting element in which a semiconductor layer is laminated on the lower surface side of a translucent substrate; a pair of electrodes formed on the lower surface of the semiconductor layer; a mounting substrate having a pair of upper surface wirings arranged so as to be opposed to a pair of electrodes respectively; a pair of conductive materials connecting the pair of electrodes to the pair of upper surface wirings; internal wirings extended from the upper surface wirings to the side surface or the lower surface of the mounting substrate, while passing through the inside of the mounting substrate; and a wavelength converting member attached to the upper surface and the side surface of the semiconductor light emitting element, and comprising fluorescent substance for converting at least one part of wavelength of emitted light projected out of the semiconductor light emitting element. In this case, the semiconductor light emitting element covers the upper surface wirings in the plan view; and the electrode is connected to the upper surface wirings through a conductive material so that the lower surface of semiconductor light emitting element and the upper surface of the mounting substrate are apart from each other, while the wavelength converting member is formed on the lower surface of the semiconductor light emitting element also. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a light emitting device including a semiconductor light emitting element and a method for manufacturing the same, and more particularly to a white light emitting device using a nitride semiconductor light emitting element and a method for manufacturing the same.

  Blue light emitting diodes using nitride semiconductors are used in white light emitting devices in combination with fluorescent materials that emit yellow light. When a fluorescent material is placed on the light emitting surface side of the light emitting diode and part of the emitted blue light is converted into yellow light by the fluorescent material, the yellow light is mixed with the blue light that has passed through without being converted to white, and the white light Light is obtained.

In order to make the chromaticity of the white light uniform, it is necessary to arrange the fluorescent material equally on the optical path of the light emitted from the light emitting diode. As one of the methods, a technique is known in which a fluorescent substance is electrophoresed in a solution in which a charged fluorescent substance is dispersed (see, for example, Patent Document 1). In electrophoresis, a light emitting diode and an electrode are placed in a solution, and a voltage is applied between them. At this time, the voltage is generated so that a potential opposite to that of the fluorescent material band electrode is generated in the light emitting diode. Is applied, the fluorescent material is attracted to the conductive portion of the light emitting diode. If a binder for adhering the fluorescent material to the surface of the light emitting diode is included in the solution, a uniform layer (wavelength converting member) of the fluorescent material can be formed on the surface of the light emitting diode.
JP 2003-69086 A

  When the electrophoresis deposition technique as in Patent Document 1 is used, a fluorescent substance is often attached to the light emitting diode in a state immediately before completion. This is because when a die bonding or wire bonding is performed after electrodeposition, there is a problem if a fluorescent material adheres to the surface of the pad electrode. Therefore, the pad electrode can be masked before electrodeposition or the pad electrode can be formed after electrodeposition. This is because it is necessary to remove the fluorescent material on the surface of the electrode. If die bonding or wire bonding is performed before electrodeposition, the troubles thereof can be saved. In this case, in the light-emitting diode mounted face-up, the fluorescent material is attached in a state where the wire bonding is completed. Therefore, a wavelength conversion member is also formed on the conductive wire for wire bonding. That is, the light emitting diode has a long wavelength conversion member along the conductive wire, which causes an increase in light loss. In addition, the conductive wire to which the wavelength conversion member is attached has a problem that it loses flexibility and is easily cut.

  As means for avoiding these problems, there is a method of flip-chip mounting a light emitting diode. In the example of the flip chip mounting disclosed in Patent Document 1, a reflection layer is formed on the semiconductor layer side in order to extract the light emitted toward the submount from the light generated in the active layer of the light emitting diode. ing. That is, the light can be extracted only from the light-transmitting substrate side and the side surface of the light-emitting diode without going out to the submount side. Since unnecessary wavelength conversion members cause light loss, electrophoretic deposition is performed by masking so that the fluorescent material does not adhere to other than the light exit surface.

However, it is substantially difficult for the reflective layer to completely prevent light that passes through to the submount side of the light emitting diode. In Patent Document 1, an n-side electrode and a p-side electrode have a reflective structure, and a reflective layer is also formed on an n-type semiconductor layer on which the n-side electrode is not formed. However, a notch is formed to expose the n-type semiconductor layer. There is no reflective layer on the side surface of the p-type semiconductor layer formed at the time, and light leaks from the side surface. Since light easily leaks even in a narrow gap, the leaked light from the side face leaks out of the light emitting device through the gap between the light emitting diode and the submount.
This leaked light goes out of the light emitting device through a path that does not pass through the wavelength conversion member, causing a blue ring in the white light source.

  Therefore, an object of the present invention is to provide a light emitting device that can suppress light loss caused by optical waveguide in a wavelength conversion member and that does not generate leaked light that is not wavelength converted, and a method for manufacturing the same.

  A light-emitting device of the present invention includes a semiconductor light-emitting element in which a semiconductor layer is stacked on the lower surface side of a light-transmitting substrate, a pair of electrodes formed on the lower surface of the semiconductor layer, and each of the pair of electrodes. The mounting substrate having a pair of upper surface wirings arranged opposite to each other, at least a pair of conductive materials connecting the pair of electrodes and the pair of upper surface wirings, and the mounting from the upper surface wiring through the inside of the mounting substrate A wavelength conversion member including an internal wiring extending to a side surface or a lower surface of the substrate, a fluorescent material attached to the upper surface and the side surface of the semiconductor light emitting device, and wavelength-converting at least part of light emitted from the semiconductor light emitting device; The semiconductor light emitting element covers the upper surface wiring in a plan view, and the pair of electrodes and the lower surface of the semiconductor light emitting element and the upper surface of the mounting substrate are separated from each other. Above A pair of top wires are connected by a conductive material, wherein the wavelength conversion member to the lower surface of the semiconductor light emitting element is formed.

  In this light-emitting device, since the wavelength conversion member is also formed on the lower surface of the semiconductor light-emitting element, it is possible to wavelength-convert leaked light to the mounting substrate side that has not been considered so far. Thereby, it is possible to completely eliminate the leakage light from causing ring-shaped color unevenness in the irradiation light of the light emitting device.

  Further, in this light emitting device, since the semiconductor light emitting element covers the upper surface wiring in a plan view, masking is not necessary when forming the wavelength conversion member. Here, “plan view” means observation from the light emitting surface side of the semiconductor light emitting element, that is, the light transmitting substrate side. If the upper surface wiring is covered with the semiconductor light emitting element in plan view, the conductive material connecting the upper surface wiring and the electrode of the semiconductor light emitting element is also covered with the semiconductor light emitting element in plan view. Therefore, when the wavelength conversion member is formed by electrophoretic deposition, the fluorescent material does not protrude from the plan view of the semiconductor light emitting element, and therefore masking as in the cited document 1 is not required.

  The fact that masking is not necessary when forming the wavelength converting member has the advantage that not only the number of processes is reduced, but the masking layer does not block or block the semiconductor light emitting element. This is extremely important in forming the wavelength conversion member on the lower surface of the semiconductor light emitting device. That is, in an example of the present invention, the lower surface of the semiconductor light emitting device and the upper surface of the mounting substrate are separated by a conductive material, so that the solution used for electrophoresis deposition contacts the lower surface of the semiconductor light emitting device, and the fluorescent material is a semiconductor. The wavelength conversion member is formed on the lower surface of the semiconductor light emitting device by reaching the lower surface of the light emitting device. However, when the masking as in the cited document 1 is formed, the gap between the lower surface of the semiconductor light emitting element and the upper surface of the mounting substrate becomes narrow, so that the solution cannot enter and the periphery of the gap is completely blocked. There's a problem. If the wavelength conversion member is formed on the lower surface of the semiconductor light emitting device while forming the masking, the lower surface of the semiconductor light emitting device and the upper surface of the mounting substrate are separated from each other by increasing the height of the conductive material. There is a method, but this increases the height of the apparatus and the number of steps.

  Therefore, according to the present invention, since the semiconductor light emitting element covers the upper surface wiring in a plan view, masking is not required for forming the wavelength conversion member by electrophoretic deposition. There is an effect that the conversion member can be reliably formed.

In addition, the method for manufacturing the light emitting device of the present invention is suitable for manufacturing the above light emitting device. That is, the present invention relates to a semiconductor light emitting device in which a semiconductor layer having a light emitting function is stacked on the lower surface side of a translucent substrate, a pair of electrodes formed on the lower surface of the semiconductor layer, and each of the pair of electrodes. A mounting substrate having a pair of upper surface wirings arranged opposite to each other and connected by a conductive material, and at least a pair of conductive materials connecting the pair of electrodes and the pair of upper surface wirings;
Internal wiring extending from the upper surface wiring to the side surface or lower surface of the mounting substrate through the inside of the mounting substrate, and light emitted from the semiconductor light emitting device and attached to the upper surface and side surfaces of the semiconductor light emitting device A wavelength conversion member including a fluorescent material that converts a wavelength of at least a part of the light emitting device, wherein the lower surface of the semiconductor light emitting element and the upper surface of the mounting substrate are spaced apart from each other. A pair of electrodes and the pair of upper surface wirings are connected by a conductive material, and the semiconductor light emitting element is disposed so as to cover the upper surface wiring in a plan view, and the semiconductor light emitting element and the mounting substrate are Immersion in a conductive solution containing a fluorescent material, the solution reaches between the lower surface of the semiconductor light emitting element and the upper surface of the mounting substrate, and the semiconductor in the solution By applying the device voltage to the optical element and the mounting substrate, wherein the depositing the fluorescent substance upper surface, the side surface and the lower surface of the semiconductor element.

  This manufacturing method uses electrophoretic deposition of a fluorescent material in the same manner as Patent Document 1 in forming the wavelength conversion member. At this time, the lower surface of the semiconductor light emitting element and the upper surface of the mounting substrate are in a separated state. A wavelength conversion member having a uniform thickness can be formed on the lower surface and side surfaces as well as the upper surface of the semiconductor light emitting device.

  The light emitting device of the present invention has a high light emission efficiency because there is little loss of light caused by the optical waveguide in the wavelength conversion member, and does not produce leaked light that has not been wavelength converted. Become. In addition, the method for manufacturing a light-emitting device of the present invention can manufacture a light-emitting device with good luminous efficiency and little color unevenness.

As shown in FIG. 1, the light-emitting device 10 according to the first embodiment includes a mounting substrate 14 and a semiconductor light-emitting element 12 that is flip-chip mounted on the mounting substrate 14.
The semiconductor light emitting element 12 is configured by laminating an n-type semiconductor layer 18, an active layer 20, and a p-type semiconductor layer 22 on the lower surface 16 b side of the translucent substrate 16, and further, a lower surface of the p-type semiconductor layer 22. The p-side electrode 24 is formed. Further, the p-type semiconductor layer 22 and the active layer 20 (and a part of the thickness of the n-type semiconductor layer 18 as necessary) so that the n-type semiconductor layer 18 is exposed on the lower surface side of the semiconductor light emitting element 12. However, the recess 26 is formed by partial removal. An n-side electrode 28 is formed on the lower surface of the n-type semiconductor layer 18 exposed from the recess 26.

The mounting substrate 14 is formed of an insulator, and the upper surface wirings 30 and 32 are provided on the upper surface 14 a on which the semiconductor light emitting element 12 is mounted at positions corresponding to the p-side electrode 24 and the n-side electrode 28 of the semiconductor light emitting element 12. Is formed. The upper surface wirings 30 and 32 are connected to the lower surface 14 b of the mounting substrate 14 by internal wirings 34 and 36 routed inside the mounting substrate 14.
The mounting substrate 14 provided with the internal wirings 34 and 36 can have various structures using a known technique. In the example of the mounting substrate 14 of FIG. 1, two members, a first member 141 having a through hole immediately below the upper surface wirings 30 and 32, and a second member 142 having notches 38 and 38 are joined. Has been. The through holes of the first member 141 are filled with first conductive members 341 and 361 such as a conductive paste, and the second conductive member such as a metal film is also formed on the surface of the notches 38 and 38 of the second member 142. 342 and 362 are covered. Then, after forming the third conductive members 343 and 363 connecting the first conductive members 341 and 361 and the second conductive members 342 and 362, respectively, between the first member 141 and the second member 142, the first member By mounting 141 and the second member 142, the mounting substrate 14 including the internal wirings 34 and 36 is obtained.

  The p-side electrode 24 and the n-side electrode 28 of the semiconductor light emitting element 12 are connected to the two upper surface wirings 30 and 32 of the mounting substrate 14 by conductive materials (in this example, metal bumps) 56 and 58, respectively. Since the semiconductor light emitting element 12 is supported on the upper surface 14a of the mounting substrate 14 by the metal bumps 56, 58, the lower surface 12b of the semiconductor light emitting element 12 and the upper surface 14a of the mounting substrate 14 are connected to the metal bumps 56, 58. Is spaced apart by a distance d corresponding to the sum of the thickness of the electrodes 24 and 28 of the semiconductor light emitting element and the thickness of the surface wirings 30 and 32.

  A wavelength conversion member 40 having a substantially uniform thickness is formed on the upper surface 12a, the lower surface 12b, and the side surface 12c of the semiconductor light emitting element 12 of the light emitting device 10. The wavelength conversion member 40 includes a fluorescent material 44 that converts the wavelength of light emitted from the semiconductor light emitting element 12. The light generated in the active layer 20 of the semiconductor light emitting device 12 is emitted in all directions of the upper surface 12a direction, the lower surface 12b direction, and the side surface 12c of the semiconductor light emitting device 12, and is extracted outside. When the light from the semiconductor light emitting element 12 passes through the wavelength conversion member 40, the light is partially absorbed by the fluorescent material 44, converted in wavelength, and mixed with the light that has not been absorbed. In the light emitting device 10 of the present embodiment, light emitted from any surface of the semiconductor light emitting element 12 passes through the wavelength conversion member having substantially the same thickness, so that the light whose wavelength is converted by the fluorescent material 44 The ratio can also be made almost constant, and color unevenness is reduced. In particular, since the wavelength conversion member 40 is also formed on the lower surface 12b of the semiconductor light emitting device 12, the leakage light to the mounting substrate 14 side that has not been considered so far can also be wavelength converted. Thereby, it is possible to completely eliminate the leakage light from causing ring-shaped color unevenness in the irradiation light of the light emitting device 10.

  The wavelength conversion member 40 covers not only the semiconductor light emitting element 12 but also conductive portions exposed to the outside, such as the p-side electrode 24, the n-side electrode 28, the metal bumps 56 and 58, and the upper surface wirings 30 and 32. In the light emitting device of the present invention, the upper surface wirings 30 and 32 are within the range L in the front view of the semiconductor light emitting element 12, and the electrodes 24 and 28 are also formed on the lower surface of the semiconductor light emitting element 12. The metal bumps 56 and 58 that are hidden in the range L and connect the upper surface wirings 30 and 32 and the electrodes 24 and 28 are also arranged in the range L. Therefore, the wavelength conversion member 40 attached to the surfaces of the electrodes 24 and 28, the upper surface wirings 30 and 32, and the metal bumps 56 and 58 does not protrude from the wavelength conversion member 40 on the surface of the conductor light emitting element 12, and the light emission of the light emitting device 10. Does not distort the profile. That is, the wavelength conversion member 40 guides light within the layer, but the wavelength conversion member 40 is formed when the light emitting device 10 is observed from above by forming the conductive member in a narrower range than the semiconductor light emitting element 12. Thus, the light guided in step S does not appear to protrude from the semiconductor light emitting device 12. In addition, since the wavelength conversion member 40 is formed in a relatively narrow range, the attenuation of light caused by the wave guide in the wavelength conversion member 40 can be suppressed, and the extraction efficiency can be improved.

  The wavelength conversion member 40 includes a fluorescent material, but preferably further includes an insulating binder for fixing the fluorescent material. Further, the fluorescent material and the binder may be further covered with a light-transmitting resin. Thereby, the fluorescent substance and the binder can be more firmly fixed to the semiconductor light emitting element and can be protected from the external environment. Note that the light-transmitting resin is preferably formed away from the semiconductor light-emitting element by a binder, thereby suppressing coloring deterioration due to light from the semiconductor light-emitting element. Moreover, it is preferable that the refractive index of a binder is larger than the refractive index of translucent resin. By gradually reducing the refraction in the light extraction direction, the light from the light-emitting element or the light whose wavelength has been converted by the fluorescent material contained in the binder is efficiently reflected in the emission observation direction without being totally reflected. Is done. Therefore, a light emitting device with high light extraction efficiency can be obtained.

  In the present invention, the electrophoretic deposition of the fluorescent substance 44 can be used in the same manner as Patent Document 1 in forming the wavelength conversion member 40. According to the electrophoretic deposition, the wavelength conversion member 40 having a uniform thickness can be formed on the lower surface 12b and the side surface 12c as well as the upper surface 12a of the semiconductor light emitting device 12.

The formation of the wavelength conversion member 40 will be described with reference to FIG.
As shown in FIG. 2, the light emitting device 10 is fixed on the support electrode 50 and immersed in a solution (electrolytic solution) 46 in the electrodeposition bath 42. A charged fluorescent substance 44 is dispersed in the solution 46. A counter electrode 48 is installed to face the support electrode 50, and a voltage is applied between the support electrode 50 and the counter electrode 48 by an external power source 52. At this time, by applying a voltage having a polarity different from that of charging of the fluorescent substance 44 to the support electrode 50, a voltage is also applied to the semiconductor light emitting element 12 through the internal wirings 34 and 36, and the fluorescent substance 44 in the solution 46. Migrates toward the semiconductor light emitting element 12. Since the conductive portion of the surface of the light emitting element 12 is charged with a polarity opposite to that of the fluorescent material 44, the fluorescent material 44 is deposited on the surface with a uniform film thickness. If the excess solvent contained in the deposit is removed by drying the deposit, the wavelength conversion member 40 including the fluorescent material as shown in FIG. 1 can be formed with a substantially uniform film thickness.

  Here, if the translucent substrate 16 of the semiconductor light emitting device 12 is a conductive material, the fluorescent substance 44 adheres to the entire surface of the semiconductor light emitting device 12. However, when the translucent substrate 16 is an insulator material, the fluorescent substance 44 does not adhere to the surface of the translucent substrate, and thus the wavelength conversion member 40 can be formed on the translucent substrate 16. Can not. In such a case, a conductive film covering the surface of the insulator substrate can be formed.

  In the light emitting device 10 of FIG. 3, a conductive film 60 that covers the surface of the insulating substrate 16 is formed. Since the conductive film 60 also remains in the light emitting device 10 as a final product, light transmission is required in addition to conductivity, and for example, a metal thin film or a conductive oxide can be used. In addition, the conductive film 60 needs to be formed so as not to short-circuit the n-type semiconductor layer 18 and the p-type semiconductor layer 22. For example, as shown in FIG. 3, if the conductive coating 60 is formed so as to be in contact with the insulating substrate 16 and the n-type semiconductor layer 18 and not to be in contact with the active layer 20 and the p-type semiconductor layer 24, during electrophoretic deposition. A voltage can be applied via the n-type semiconductor layer 18, and when used as the light emitting device 10, there is no short circuit.

  As another method for forming the wavelength conversion member 40 on the insulating substrate, there is a method in which the conductive film 60 that gradually dissolves during the electrophoresis deposition process and does not remain in the light emitting device 10 of the final product is used. is there. As an example, there is a method in which a conductive coating 60 made of an aluminum thin film is formed on an insulating substrate, and electrophoretic deposition is performed using a conductive sol solution 46 containing aluminum alcoholate as a material and containing nitric acid. The aluminum thin film gradually dissolves during electrophoresis deposition, and almost dissolves when the electrophoresis is completed. In addition, when the aluminum thin film remains slightly undissolved, it can be oxidized by oxidizing the phosphor layer when it is dried and fired to make it insulating. According to this method, even if the conductive coating 60 is formed over the surfaces of the n-type semiconductor layer 18 and the p-type semiconductor layer 22, the conductive film 60 is finally removed or insulated. In this case, there is no possibility that the n-type semiconductor layer 18 and the p-type semiconductor layer 22 are short-circuited.

  In addition, since the conductive film 60 is for causing the charged fluorescent substance 44 in the solution 46 to be electrophoresed on the surface of the insulating substrate, the conductive film 60 is limited to a form in which the conductive film 60 is directly formed on the semiconductor light emitting element 12. However, another member (for example, translucent resin or glass) may be disposed between the conductive coating 60 and the semiconductor light emitting element 12. Therefore, a translucent insulating material can be interposed in a necessary portion between the conductive film 60 and the semiconductor light emitting element 12 so that the n-type semiconductor layer 18 and the p-type semiconductor layer 22 are not short-circuited.

  The solution 46 used for the electrophoretic deposition may contain a binder or a charging material in addition to the fluorescent substance 44. In that case, the formed wavelength conversion member 40 includes a binder and a charging material in addition to the fluorescent material 44. Furthermore, the wavelength conversion member 40 may have a translucent resin that covers the fluorescent material and the binder. In the wavelength conversion member 40, the fluorescent material only needs to be arranged so that the wavelength of light emitted from the semiconductor light emitting element can be converted, and another light-transmitting member is interposed between the semiconductor light emitting element and the fluorescent material. It does not matter.

  As shown in FIG. 1, the semiconductor light emitting device 12 of the present invention is characterized in that the lower surface 12b also includes a wavelength conversion member 40. In particular, the wavelength conversion member 40 has a thickness other than that of the other surface (upper surface 12a). And the wavelength conversion member 40 on the side surface 12c). However, when the wavelength conversion member 40 is formed by electrophoretic deposition, since the semiconductor light emitting element 12 is mounted on the mounting substrate 12, the gap 62 between the lower surface 12b of the semiconductor light emitting element 12 and the upper surface 14a of the mounting substrate 14 is separated. When the distance d is narrow, the electrophoretic deposition solution 46 does not enter the gap 62, so that the wavelength conversion member 40 is not formed on the lower surface 12 b of the semiconductor light emitting device 12. Even if the solution 46 can enter the gap 62, the amount of the fluorescent substance 44 entering the gap 62 is small and formed on the lower surface 12 b unless it is sufficiently separated from the particle size of the fluorescent substance 44. The thickness of the wavelength conversion member 40 is reduced. Therefore, it is preferable to set the lower limit of the separation distance d so that the wavelength conversion member 40 grows to an appropriate thickness. Depending on the viscosity of the solution and the particle size of the fluorescent substance 44 to be used, if the separation distance is 5 μm or more, most of the solution 46 used for electrophoretic deposition can enter, and the grains of the fluorescent substance 44 that are often used Since it is sufficiently wider than the diameter, it is preferable because the wavelength conversion member 40 can be formed on the lower surface 12b of the semiconductor light emitting element 12.

In order to grow the wavelength conversion member 40 on the semiconductor light emitting device 12 and the lower surface 12b, it is also effective to devise the arrangement of the conductive materials (metal bumps) 56 and 58. Since the metal bumps 56 and 58 block the migration of the fluorescent substance 44, the growth of the wavelength conversion member 40 is delayed depending on the arrangement method of the metal bumps 56 and 58. Therefore, a path through which the fluorescent material 44 can enter is preferably formed between the p-side metal bump 56 and the n-side metal bump 58. The shape of this path is determined by the shapes of the upper surface wirings 30 and 32 of the mounting substrate 14 connected by the metal bumps 56 and 58 and the p-side electrode 24 and the n-side electrode 28 of the semiconductor light emitting element 12.
4A and 4B show an example of the shapes of the p-side electrode 24 and the n-side electrode 28 of the semiconductor light emitting device 12 suitable for the present invention and the upper surface wirings 30 and 32 of the mounting substrate 14.

FIG. 4A illustrates the semiconductor light emitting element 12 with the semiconductor layer side facing upward so that the electrode shape can be easily understood. As shown in the figure, the p-side electrode 24 is formed in a T-shape, the n-side electrode 28 is formed in a U-shape, and a part of the p-side electrode 24 is disposed in a rectangular space of the n-side electrode 28. . The p-side electrode 24 and the n-side electrode 28 are spaced apart from each other by facing sides. This interval becomes the entry path R of the fluorescent substance 44.
The n-side electrode 28 partially contacts the n-type semiconductor layer 18 exposed from the recess 26 and extends to the surface of the p-type semiconductor layer 22. At this time, the insulating layer 54 is interposed so that the n-side electrode 28 does not directly contact the side surface of the recess 26 and the surface of the p-type semiconductor layer 22. By so doing, the area where the p-type semiconductor layer 22 and the active layer 20 are removed can be reduced compared to the area of the n-side electrode 28, and the output of the semiconductor light emitting device 12 can be improved.

  The upper surface wirings 30 and 32 of the mounting substrate 14 shown in FIG. 4B are formed in accordance with the electrode shape of the semiconductor light emitting device 12 of FIG. 4A, the p-side upper surface wiring 30 is T-shaped, and the n-side upper surface wiring 32 is Are the same dimensions as those of the electrodes 24 and 28 and are arranged in the same positional relationship.

It is preferable to form metal bumps 56 and 58 on the upper surface wirings 30 and 32 of the mounting substrate 14 before mounting the semiconductor light emitting element 12. In particular, it is preferable to form a plurality of metal bumps 56 and 58 over the entire upper surface wiring 30 and 32 because the semiconductor light emitting element 12 becomes stable when mounted. Further, the heights of the metal bumps 56 and 58 affect the distance d between the lower surface 12b of the semiconductor light emitting element 12 and the mounting substrate 14a, and thus are appropriately adjusted in consideration of the spread during reflow.
At the time of mounting, the semiconductor light emitting element 12 is inverted so that the semiconductor layer faces downward, and the electrodes 24 and 28 of the semiconductor light emitting element 12 are positioned so as to coincide with the upper surface wirings 30 and 32 of the mounting substrate 14, thereby The semiconductor light emitting device 12 is placed on the 56 and 58. The metal bumps 56 and 58 are reflowed to complete the mounting of the semiconductor light emitting element 12.

5A to 5D illustrate the p-side electrode 24 and the n-side electrode 28 of the semiconductor light emitting device 12 that can form the penetration path R of the fluorescent material 44 suitable for the present invention. The upper surface wirings 30 and 32 of the mounting substrate 14 are substantially the same as the electrode shape of the semiconductor light emitting element 12.
5A and 5B, the n-side electrode 28 is made smaller and formed only in the recess 26. Instead, the p-side electrode 24 is formed long to secure the area where the metal bumps are formed, thereby improving the stability of the semiconductor light emitting device 12 during mounting. The fluorescent substance 44 moves along the penetration path R and reaches the lower surface 12 b of the semiconductor light emitting element 12. As shown in the figure, when the sides facing the p-side electrode 24 and the n-side electrode 28 are curved, the fluorescent material 44 traveling through the penetration path R does not stagnate locally. It is effective to spread.

5C and 5D show the p electrode 24 and the n electrode 28 having the same shape. In either case, since the n-side electrode 24 is large, the n-side electrode 24 extends from the recess 26 onto the p-type semiconductor layer 22. As in FIG. 4A, the insulating layer 54 is formed so that the n-side electrode 28 does not directly contact the side surface of the recess 26 and the surface of the p-type semiconductor layer 22.
In FIG. 5C, since the intrusion route R of the fluorescent material 44 is formed so as to spread outward, the fluorescent material 44 easily enters the intrusion route R.
Further, in FIG. 5D, since the intrusion route R is straight, the fluorescent material 44 is difficult to stagnate in the middle of the route, and the fluorescent material 44 can be uniformly attached to the entire lower surface 12b of the semiconductor light emitting element 12.

(Electrophoretic deposition)
Details of the electrophoresis deposition will be described below.
(A) Electrodeposition bath 42
Various electrolyte solutions 46 in the electrodeposition bath 42 can be used. As the solvent, non-aqueous solvents such as isopropyl alcohol and acetone are preferable. As the electrolyte, for example, magnesium nitrate or the like can be added. If a fluorescent substance such as YAG is dispersed therein, the YAG fluorescent substance is positively charged because the zeta potential of the YAG fluorescent substance is positive. Therefore, if the semiconductor light emitting device 1 is charged to a negative polarity, the fluorescent material migrates toward the semiconductor light emitting device 12, and the fluorescent material can be deposited on the surface of the nitride semiconductor 1. A resin layer or the like having an appropriate binding action may be formed on the surface of the fluorescent material particles so that the fluorescent material 44 can be fixed to the surface of the semiconductor light emitting element 12. Is preferably included.

  The binder contained in the electrolytic solution 46 is an organic metal containing at least one element selected from Si, Al, Ga, Ti, Ge, P, B, Zr, Y, Sn, Pb, and an alkaline earth metal. It is preferably formed from a compound (preferably further containing oxygen). When these organometallic compounds are electrophoretic deposited using a non-aqueous sol solution, a uniform wavelength conversion member can be formed without generating bubbles such as hydrogen gas. Further, the organometallic compound finally becomes a binder composed of an oxide by a hydrolysis reaction or the like. Here, the organometallic compound includes a compound containing an alkyl group or an aryl group. Examples of such organometallic compounds include metal alkoxides, metal diketonates, metal diketonate complexes, and carboxylic acid metal salts. Of these, metal alkoxides are preferred. If an organometallic compound that is liquid at room temperature is used, it can be easily dissolved in a solvent such as IPA. If it does so, workability | operativity can be improved since the viscosity adjustment of the electrolyte solution which considered workability | operativity and generation | occurrence | production prevention of coagulation | solidification bodies, such as an organometallic compound, in electrolyte solution can be made easy. In addition, such an organometallic compound tends to be an oxide by a chemical reaction such as hydrolysis. Therefore, if the fluorescent substance is dispersed in a sol solution made of these organometallic materials, electrophoretic deposited, and dried to remove the solvent, the fluorescent substance can be fixed by the oxide containing the element. Further, when a fluorescent substance is dispersed in a sol solution made of these organometallic materials, the fluorescent substance is encapsulated by the sol made of the organometallic material and is charged. Therefore, since the fluorescent material can be charged with the binder material itself without having to previously charge the fluorescent material, the light emitting device can be manufactured with good workability.

Hereinafter, more specific examples of the binder will be described.
(Binder with SiO ₂ )
The binding material in which the fluorescent substance is fixed by SiO ₂ is a uniform dispersion of the fluorescent substance (powder) in a silica sol obtained by mixing an alkyl silicate and a non-aqueous solvent such as alcohol or acetone in a predetermined ratio. The prepared mixed solution can be prepared and electrophoretically deposited in the mixed solution.

The alkyl silicate is a product obtained by hydrolyzing a monomer (monomer) represented by the following general formula such as [Formula 1] and further performing polycondensation. Here, R is an alkyl group, which is methyl silicate in the case of methyl group, ethyl silicate in the case of ethyl group, N-propyl silicate in the case of n-propyl group, and N-butyl silicate in the case of n-butyl group.
[Formula 1]

Ethyl silicate, which is a kind of alkyl silicate, has the following structure, and is a colorless and transparent liquid mainly synthesized from the reaction of silicon tetrachloride with ethanol or the reaction of metal silicon with ethanol. That is, in the above general formula, a monomer (monomer) represented by a structural formula in which R is an ethyl group is hydrolyzed to contain a hydroxyl group (OH group) -containing molecule (an intermediate monomer such as a silanol monomer). Furthermore, water molecules (H ₂ O) are taken from and condensed with molecules containing hydroxyl groups (OH groups), and a siloxane bond in which Si is connected via oxygen is generated. ] Is obtained.
[Formula 2]

When an ethyl silicate solution is reacted with water in the presence of a catalyst, the solution becomes a sol solution in which colloidal particles of SiO ₂ are dispersed by a hydrolysis reaction as shown in [Formula 3] below (solation). . Furthermore, the hydrolysis reaction proceeds, and the solution is dried, so that the solution concentration becomes high and gelation occurs. Although the viscosity increases as the reaction proceeds, the progress of the reaction is adjusted in consideration of workability and the like.

[Formula 3]

The hydrolysis reaction proceeds very slowly under neutral conditions, but proceeds rapidly with heat generation in the presence of an acid or base as a catalyst. When using a basic catalyst, the resulting hydrolysis solution is unstable and easily gelled excessively, so that the workability is lowered. Therefore, it is preferable to use a small amount of an acidic catalyst such as hydrochloric acid and perform the hydrolysis reaction over a long period of time. .

The hydrolysis reaction of ethyl silicate proceeds faster as the temperature increases, and proceeds more readily when the product ethanol is removed. Further, when the gel generated by the hydrolysis of ethyl silicate is heated, SiO ₂ is formed. Therefore, when a phosphor substance is contained in a sol solution of ethyl silicate and electrophoretically deposited on the surface of the light-emitting element, and dried to remove the solvent, a binder formed by fixing the phosphor substance with SiO ₂ is added to the light-emitting element. It is formed.
In particular, in this embodiment, ethyl silicate is used in advance as a sol-state hydrolysis solution, and a fluorescent substance is contained in the hydrolysis solution, and then electrophoretically deposited on the surface of the light-emitting element. If the electrolyte containing a fluorescent material contains a lot of water, hydrogen is generated when electrophoresis is deposited and the surface condition of the wavelength conversion member deteriorates, which may adversely affect the optical characteristics of the light emitting device. is there. The ethyl silicate hydrolysis solution in the sol state contains almost no water. Therefore, the wavelength conversion member can be easily formed without adversely affecting the optical characteristics of the light emitting element.

By appropriately adjusting the reaction conditions, the binder can contain trace amounts of Si (OH) ₄ that is an intermediate for generating SiO ₂ , ethyl silicate and ethanol that are starting materials. Due to the presence of inorganic substances such as Si (OH) ₂ and organic substances such as unreacted ethyl silicate and ethanol in the binder, the surface of the binder has strong polar functions such as hydroxyl groups and ethyl groups. The group will be present. Due to the presence of such a functional group, familiarity with a hydrophobic material having polarity such as a fluororesin or a sealing resin having a hydroxyl group at the end of the molecular structure, or wettability is improved. Therefore, even if a small amount of the sealing resin is used, the sealing resin can be disposed on the binder with good adhesiveness. In addition, the presence of a large amount of inorganic substances such as SiO ₂ and Si (OH) _{2 in the} binder can not only prevent the binder from deteriorating due to high output light from the semiconductor element, but also the semiconductor element or the semiconductor. The familiarity or wettability with the conductive film 60 formed on the surface of the light emitting element is improved. This is considered to be caused by electrostatic coupling between SiO ₂ , Si (OH) ₂ , and the like and metal ions contained in the semiconductor element or the conductive film 60. Therefore, the adhesive force of the binder is increased.

That is, when an organic metal compound such as ethyl silicate is used to form a binding material in which a fluorescent material is fixed by SiO ₂ , the binding material is substantially formed of an inorganic material, but also has an organic property. Because it remains a little, it is well-familiar with the surface of the semiconductor light-emitting element and the conductive coating 60, or the sealing resin provided as necessary, the manufacturing yield is improved, and the reliability is hardly deteriorated by ultraviolet rays. The light emitting device can be made high.

(Binder with Al ₂ O ₃ )
The binder mainly composed of Al ₂ O ₃ is a mixture in which a particulate fluorescent material is uniformly dispersed in an aluminum sol obtained by mixing aluminum alcoholate or aluminum alkoxide and an organic solvent in a predetermined ratio. It can be formed by performing electrophoretic deposition using a solution as a material. For example, acetone, alumina sol and a fluorescent substance are contained as organic solvents in a solution containing isopropyl alcohol as a mother liquor to obtain a mixed solution.

Aluminum alcoholate, or aluminum isopropoxide, aluminum ethoxide, and aluminum butoxide, which are a kind of aluminum alkoxide, are colorless and transparent liquids at room temperature. Produces aluminum oxide. For example, aluminum isopropoxide reacts as shown in the following [Formula 4], and finally aluminum hydroxide changes to alumina.
[Formula 4]

A sol solution containing aluminum isopropoxide can contain a particulate fluorescent material to form a mixed solution, and the particulate fluorescent material can be charged in the mixed solution. Furthermore, after the electrophoretic deposition using the mixed solution as a material, the fluorescent substance can be fixed to the semiconductor light emitting device with the generated Al ₂ O ₃ .

Below, the material suitable for each structure of this form is explained in full detail.
(Semiconductor light emitting element 12)
The semiconductor light emitting element 12 in the present embodiment will be described using an LED chip as an example. The semiconductor light emitting element 12 may be an appropriate semiconductor light emitting element other than an LED chip, such as an EL element. Examples of the light-emitting element that constitutes the LED chip include semiconductor light-emitting elements formed of various semiconductors such as ZnSe and GaN. When a fluorescent substance is used, a short wavelength that can efficiently excite the fluorescent substance. There can emit light nitride semiconductor _{(in X Al Y Ga 1-} X-Y N, 0 ≦ X, 0 ≦ Y, X + Y ≦ 1) is preferably exemplified. Examples of the structure of the semiconductor light emitting device include a homostructure having a MIS junction, a PIN junction, a pn junction, etc., a heterostructure, or a double hetero configuration. Various emission wavelengths can be selected depending on the material of the semiconductor layer and the degree of mixed crystal. In addition, a single quantum well structure or a multiple quantum well structure in which the semiconductor active layer is formed in a thin film in which a quantum effect is generated can be used.

(Translucent substrate 16)
For example, a conductive substrate such as GaN, SiC, Si, or ZnO is suitable as a material for the translucent substrate 16 for forming a semiconductor stacked body by stacking nitride semiconductors. In particular, when the nitride semiconductor layer is made of a gallium nitride compound semiconductor, it is preferable to use GaN having a small difference in thermal expansion coefficient and a difference in refractive index. In addition, GaN is preferable because the absorptivity with respect to visible light is low even in a short wavelength region near 450 nm, and thus the light emission efficiency does not decrease even when the film thickness is increased. That is, the thicker translucent substrate 2 reduces the number of multiple reflections, so that the light extraction efficiency is more efficient. However, since the absorptance in the visible light region such as SiC is high to some extent, when the thickness of the translucent substrate made of SiC or the like is increased, the light extraction efficiency is improved at a certain thickness. If the thickness is increased, absorption by the translucent substrate 2 affects the light extraction efficiency and decreases. On the other hand, in the case of the translucent substrate 2 made of GaN, since the influence of absorption is small, the light extraction efficiency increases monotonically up to about 200 μm, and the light extraction efficiency is increased even if it is thicker than that. There is no decline. Therefore, higher light extraction efficiency can be obtained as compared with SiC or the like. The translucent substrate 2 made of GaN may contain a small amount of Al, In, or the like, and may contain impurities such as Si in order to impart conductivity.

  Further, the translucent substrate 16 may be an insulating substrate such as sapphire or spinel. Among these, a sapphire substrate is preferably used. This is because the sapphire substrate can stack nitride semiconductors with good crystallinity. As the conductive coating 60 in that case, it is preferable to select a metal material having good adhesion to the sapphire substrate, for example, aluminum. As a result, peeling of the conductive film 60 hardly occurs, and a highly reliable light-emitting element can be obtained.

  The conductive film 60 is preferably subjected to a treatment for improving translucency while or after the wavelength conversion member is formed by electrophoretic deposition. That is, depending on the selection of the material of the conductive film 60 that covers the semiconductor light emitting element, the optical characteristics of the formed light emitting device may be adversely affected. For example, when the conductive film 60 is a conductive oxide such as ITO, it may be colored depending on the polarity of the voltage applied during the electrophoretic deposition. When the ITO colored in this way remains on the light emitting element, light from the light emitting element is absorbed and the light extraction efficiency of the light emitting device is lowered. In that case, it is preferable that the conductive film 60 be heated to be an oxide having high translucency with respect to light of the light emitting element.

When a metal material such as aluminum is used for the conductive film 60, the transmittance of light from the light emitting element decreases as the film thickness increases. In addition, when the conductive film 60 such as aluminum adheres directly to the side surface of the semiconductor light emitting element, the conductive film 60 itself may cause an electrical short circuit or leakage of the semiconductor light emitting element. On the other hand, in order to deposit a fluorescent material by electrophoretic deposition, a certain film thickness is required for a certain conductive film 60. Therefore, a conductive film 60 such as aluminum is formed to a certain thickness, and a material that dissolves the metal material constituting the conductive film 60 is contained in the electrophoretic deposition electrolytic solution, thereby conducting the conductive film during the electrophoretic deposition. 60 can be dissolved. By reducing the thickness of the conductive film 60 made of a metal material in this way, it is possible to suppress a decrease in light emission efficiency and electrical leakage of the semiconductor light emitting element.

In the case of using this method, the material of the conductive coating 60 is preferably a metal that is soluble in the electrolyte and has good adhesion to the light-transmitting substrate that forms the light-emitting element. Examples of the material of the conductive coating 60 include a metal material containing at least one selected from Al (aluminum), Ti (titanium), and W (tungsten). On the other hand, the electrolytic solution also has a composition capable of dissolving the conductive film 60 according to the composition of the conductive film 60. For example, when the conductive film 60 is aluminum, the sol of the organometallic compound may be an alumina sol made of aluminum alcoholate, or an acid or alkali that dissolves aluminum in the electrolytic solution, such as hydrochloric acid or nitric acid. For example, aluminum can be dissolved while immersed in the electrodeposition bath. The thickness of the conductive coating 60 is preferably set so as to have conductivity from the start to the end of electrophoretic deposition and to be converted into a member having sufficient translucency after the electrophoretic deposition step. Specifically, it is determined in consideration of the amount of the substance contained in the electrolytic solution that dissolves the conductive film 60, the voltage in the electrophoretic deposition process, the application time of the voltage, and the like.

  In the wavelength conversion member 14 thus formed, a region having a concentration gradient of the material constituting the conductive film 60 is formed in the thickness direction. For example, when the material of the conductive film 60 is aluminum and hydrochloric acid is contained in the electrolytic solution, a region in which a component (for example, aluminum ions) in which aluminum is dissolved by hydrochloric acid has a concentration gradient is formed. This concentration gradient has a concentration distribution in which the concentration is high on the side of the semiconductor light emitting element and gradually decreases as the distance from the semiconductor light emitting element increases. As a method for analyzing the concentration distribution, GDS (glow discharge emission spectroscopic analysis), SIMS (secondary ion mass spectrometry), or the like can be employed.

In addition, the process which improves the translucency of the conductive film 60 may be performed during the electrophoresis deposition, or may be performed after the electrophoresis deposition is completed. For example, after the semiconductor light emitting device 1 is taken out from the electrodeposition bath 32, the conductive film 60 and the deposit thereon are dried while being naturally dried or heated. Also during this time, the conversion of the conductive film 60 remaining after the electrophoretic deposition into the translucent member can be promoted. The conductive film 60 may remain to some extent as long as it transmits at least light from the light emitting element.

(P-side electrode 24, n-side electrode 28)
The material suitable for the p-side upper surface wiring 30 and the n-side upper surface wiring 32 is not limited as long as it is a conductive material. For example, Au or silver-white metal can be used, and in particular, Ag having high reflectivity. Al is preferred. Forming from a silver-white metal having a high reflectance is preferable because the light blocked by the electrodes 24 and 28 can be reflected and extracted from the substrate 16 side, so that the light extraction efficiency of the light emitting device is improved.

(Wavelength conversion member 40)
The wavelength conversion member 40 in this embodiment contains a fluorescent material 44 that emits light having different wavelengths by absorbing at least part of the light from the light emitting element. Such a wavelength conversion member 40 preferably includes a fluorescent material and a binder for fixing the fluorescent material. In particular, the binder is preferably a gelled product of a metal alkoxide sol solution. In addition, in order to strengthen the fixing of the wavelength conversion member to the light emitting element, other binders such as glass, translucent resin such as epoxy resin and silicone resin, and glass are formed on the fluorescent material layer formed by electrophoretic deposition. It is preferable to impregnate.

  The fluorescent substance 44 in the present embodiment converts light from the semiconductor light emitting element 12, and it is more efficient to convert light from the semiconductor light emitting element 12 to a longer wavelength. In particular, it is preferable to use a fluorescent material that converts blue light emitted from the semiconductor light emitting element 12 into yellow light because it is possible to emit white light because a light emitting device can be obtained. In particular, when the light from the semiconductor light-emitting element 12 is high-energy short-wavelength visible light, an aluminum garnet fluorescent material activated with cerium, which is a kind of aluminum oxide fluorescent material, is preferably used. Aluminum / garnet phosphors are excellent in durability, and are particularly preferable when the output of the light-emitting element 1 is high. In particular, yttrium-aluminum-garnet fluorescent material (YAG: Ce) fluorescent material activated by cerium is a yellow light that partially absorbs blue light from the LED chip and becomes a complementary color depending on its content. Therefore, it is possible to relatively easily form a high-power light-emitting diode that emits white color mixed light.

It is preferable that the fluorescent substance 44 in the forming method of the present embodiment has a shape and size that facilitates electrophoresis in the medium. In particular, for electrophoresis in an electrolytic solution, it is preferable that the fluorescent substance has a substantially spherical particle shape. Furthermore, the particle size of the particulate fluorescent material is adjusted to a particle size that is easily electrophoresed. The center particle diameter of the particulate fluorescent material in this embodiment is preferably 7 μm to 8 μm, and the average particle diameter is preferably about 6 μm.
In this specification, the particle size of the fluorescent material is a value obtained by a volume-based particle size distribution curve, and the volume-based particle size distribution curve can be obtained by measuring the particle size distribution of the fluorescent material by a laser diffraction / scattering method. Is. Specifically, in an environment of an air temperature of 25 ° C. and a humidity of 70%, a fluorescent substance is dispersed in an aqueous solution of sodium hexametaphosphate having a concentration of 0.05%, and a laser diffraction particle size distribution analyzer (SALD-2000A) It was obtained by measuring in a particle size range of 0.03 μm to 700 μm.

(Binder)
The binder is preferably an oxide containing at least one element selected from Si, Al, Ga, Ti, Ge, P, B, Zr, Y, Sn, Pb and an alkaline earth metal. Some of them may contain hydroxides of these elements. Such a binder has a strong ability to bind fluorescent substances. Therefore, the fluorescent substance in the wavelength conversion member formed in the semiconductor light emitting element is hardly peeled off, and a highly reliable light emitting device can be obtained. Further, since these binders have good insulation properties, it is possible to effectively prevent a short circuit between the p-side electrode 6 and the translucent substrate 2 due to the conductive bonding layer 16 such as solder. Among oxides containing the above elements, inorganic materials such as SiO ₂ , Al ₂ O ₃ , MSiO ₃ (M is Zn, Ca, Mg, Ba, Sr, Zr, Y, Sn, Pb, etc.) are combined. It is preferable to use a dressing. Since these inorganic materials have good translucency, the light emission efficiency of the light emitting element can be increased, and the light emitting element has high durability against strong light.

  Further, the binder containing an oxide containing at least one element selected from Si, Al, Ga, Ti, Ge, P, B, Zr, Y, Sn, Pb and an alkaline earth metal is the element described above. It can be easily formed by containing it in the electrolyte as a sol of an organometallic compound containing oxygen (preferably further containing oxygen). Examples of such organometallic compounds include metal alkoxides, metal diketonates, metal diketonate complexes, and carboxylic acid metal salts. Such an organometallic compound tends to be an oxide through a chemical reaction such as hydrolysis. Therefore, when the fluorescent substance is dispersed in a sol solution made of these organometallic materials, electrophoretic deposited, and then dried to remove the solvent, the fluorescent substance can be fixed by the oxide containing the element. Further, when a fluorescent substance is dispersed in a sol solution made of these organometallic materials, the fluorescent substance is encapsulated by the sol made of the organometallic material and is charged. Therefore, it is not necessary to use a special charging agent. In addition, if these organometallic compounds are contained in a non-aqueous solvent as a sol, hydrogen gas or the like is less likely to be generated during electrophoretic deposition, and there is no air bubbles remaining in the binder to which the fluorescent substance is fixed. It becomes a shape. Thereby, the chromaticity of the emitted light wavelength-converted by the fluorescent material can be made uniform by the emission observation direction.

  In this embodiment, the example in which the n-type semiconductor layer 18, the active layer 20, and the p-type semiconductor layer 22 are sequentially stacked on the light-transmitting substrate 16 has been described. However, the p-type semiconductor layer 22 and the n-type semiconductor are stacked. The layers 18 may be replaced and stacked. In that case, the translucent substrate 16 may be bonded to a semiconductor stacked body grown on another substrate. Further, it is sufficient that at least the n-type semiconductor layer 18, the active layer 20, and the p-type semiconductor layer 22 are included in the semiconductor stacked body so as to exhibit a light emitting function. For example, an i-type layer is included as a thin film. Also good.

(Mounting board 14)
The mounting substrate 14 is preferably made of an insulating material such as Al ₂ O ₃ , BN, C (diamond), AlN, or SiN. In particular, it is preferable to use a material having a small difference in thermal expansion coefficient from that of the semiconductor light emitting element 12, and the influence of thermal stress generated between the mounting substrate 14 and the semiconductor light emitting element 12 during manufacturing or use can be mitigated. For example, when the nitride semiconductor light emitting device 12 is used, it is preferably formed from aluminum nitride (AlN).

(Top wiring 30, 32)
The material suitable for the p-side upper surface wiring 30 and the n-side upper surface wiring 32 is not limited as long as it is a conductive material. For example, Au or silver-white metal can be used.

1 is a schematic cross-sectional view of a light emitting device according to a first embodiment. FIG. 3 is a schematic diagram illustrating electrophoretic deposition in the method for manufacturing the light emitting device according to the first embodiment. FIG. 2 is a schematic cross-sectional view before performing electrophoretic deposition on the light emitting device according to the first embodiment. 1 is a schematic perspective view of a semiconductor light emitting element for a light emitting device according to a first embodiment. 1 is a schematic perspective view of a mounting substrate for a light emitting device according to a first embodiment. 1 is a schematic bottom view of a semiconductor light emitting element for a light emitting device according to a first embodiment. 1 is a schematic bottom view of a semiconductor light emitting element for a light emitting device according to a first embodiment. 1 is a schematic bottom view of a semiconductor light emitting element for a light emitting device according to a first embodiment. 1 is a schematic bottom view of a semiconductor light emitting element for a light emitting device according to a first embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Light emitting device, 12 Semiconductor light emitting element, 12a Upper surface of semiconductor light emitting element, 12b Lower surface of semiconductor light emitting element, 12c Side surface of semiconductor light emitting element, 14 Mounting substrate, 14a Upper surface of mounting substrate, 14b Lower surface of mounting substrate, 16 substrate, 16a Upper surface of substrate, 16b Lower surface of substrate, 18 n-type semiconductor layer, 20 active layer, 22 p-type semiconductor layer, 24 p-side electrode, 26 recess, 28 n-side electrode, 30 p-side upper surface wiring, 32 n-side upper surface wiring, 34 p-side internal wiring, 36 n-side internal wiring, 40 wavelength conversion member, 42 electrodeposition bath, 44 fluorescent substance, 46 electrolyte, 56 p-side conductive material (metal bump), 58 n-side conductive material (metal bump) 62) Gap between the semiconductor light emitting element and the mounting substrate

Claims (5)

A semiconductor light emitting device in which a semiconductor layer is laminated on the lower surface side of the translucent substrate;
A pair of electrodes formed on the lower surface of the semiconductor layer;
A mounting substrate having a pair of upper surface wirings arranged to face each of the pair of electrodes;
At least a pair of conductive materials connecting the pair of electrodes and the pair of upper surface wirings;
Internal wiring extending from the upper surface wiring to the side surface or lower surface of the mounting substrate through the inside of the mounting substrate;
A wavelength conversion member that includes a fluorescent material that is attached to an upper surface and a side surface of the semiconductor light emitting element and that converts a wavelength of at least a part of light emitted from the semiconductor light emitting element.
The semiconductor light emitting element covers the upper surface wiring in a plan view,
The pair of electrodes and the pair of upper surface wirings are connected by a conductive material so that the lower surface of the semiconductor light emitting element and the upper surface of the mounting substrate are separated from each other,
The light emitting device, wherein the wavelength conversion member is also formed on a lower surface of the semiconductor light emitting element.   The light emitting device according to claim 1, wherein a lower surface of the semiconductor light emitting element is separated from an upper surface of the mounting substrate by 5 μm or more.   The light emitting device according to claim 1, wherein the wavelength conversion member further includes a binder that fixes the fluorescent substance.   The binder is an oxide containing at least one element selected from Si, Al, Ga, Ti, Ge, P, B, Zr, Y, Sn, Pb and an alkaline earth metal. The light-emitting device according to claim 3. A semiconductor light emitting device in which a semiconductor layer having a light emitting function is laminated on the lower surface side of the light transmitting substrate;
A pair of electrodes formed on the lower surface of the semiconductor layer;
A mounting substrate having a pair of upper surface wirings arranged to face each of the pair of electrodes and connected by a conductive material;
At least a pair of conductive materials connecting the pair of electrodes and the pair of upper surface wirings;
Internal wiring extending from the upper surface wiring to the side surface or lower surface of the mounting substrate through the inside of the mounting substrate;
A wavelength conversion member including a fluorescent material that is attached to an upper surface and a side surface of the semiconductor light-emitting element and converts the wavelength of at least a part of light emitted from the semiconductor light-emitting element. ,
The pair of electrodes and the pair of upper surface wirings are connected by a conductive material so that the lower surface of the semiconductor light emitting device and the upper surface of the mounting substrate are separated from each other, and the semiconductor light emitting device is seen in plan view Arranged to cover the top wiring,
The semiconductor light emitting device and the mounting substrate are immersed in a conductive solution containing the fluorescent material, and the solution reaches between the lower surface of the semiconductor light emitting device and the upper surface of the mounting substrate,
A method for manufacturing a light emitting device, comprising: applying a device voltage to the semiconductor light emitting element and the mounting substrate in the solution to attach the fluorescent material to an upper surface, a side surface, and a lower surface of the semiconductor element.

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