JP2010251481A - Light-emitting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light-emitting device which has an excellent heat dissipation property and enhances an optical output. <P>SOLUTION: This light-emitting device 20 has: a semiconductor light-emitting element 1 which is formed on the one surface side of a zinc oxide substrate 1a, and is provided with an LED thin film part 1b having a p-type nitride semiconductor layer 11 and an n-type nitride semiconductor layer 13; and a packaging substrate 2 for packaging the semiconductor light-emitting element 1 through metal bumps 3 and 4 so that the other surface side in the zinc oxide substrate 1a of the semiconductor light-emitting element 1 becomes a light fetching face. The semiconductor light-emitting element 1 is provided with the LED thin film part 1b smaller than the zinc oxide substrate 1a so as to expose an outer peripheral part 1d on the one surface side of the zinc oxide substrate 1a in plan view, and the metal bumps 3 and 4 include: a plurality of first metal bumps 3 provided in the outer peripheral part 1d of the zinc oxide substrate 1a so as to surround the LED thin film part 1b; and a plurality of second metal bumps 4 provided on the surface side opposite to the zinc oxide substrate 1a in the LED thin film part 1b. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a light emitting device in which a semiconductor light emitting element using a nitride semiconductor is mounted on a mounting substrate.

  Conventionally, research on semiconductor light emitting devices using nitride semiconductor materials (GaN, AlGaN, InGaN, AlInGaN, etc.) has been conducted in various places. A light-emitting device in which this type of semiconductor light-emitting element is mounted on a mounting substrate has, for example, a semiconductor light-emitting element and a longer wavelength than blue light emitted from the semiconductor light-emitting element, excited by blue light emitted from the semiconductor light-emitting element. A wavelength conversion member containing a phosphor that emits yellow light can be used in combination to emit mixed color light (for example, white light) having a hue different from the emission color of the semiconductor light emitting element. A light-emitting device that can emit white light using such a semiconductor light-emitting element can emit light with lower power consumption, higher brightness, and longer life than a light bulb or the like. It is attracting attention as one of alternatives, and research and development are being carried out for higher efficiency and higher output.

  As a basic configuration of this type of light emitting device, a semiconductor including an LED thin film portion in which an n-type nitride semiconductor layer and a p-type nitride semiconductor layer on the n-type nitride semiconductor layer are stacked on one surface side of a substrate There is known a light emitting device having a light emitting element and a mounting substrate on which the semiconductor light emitting element is mounted via a metal bump so that the other surface side of the substrate of the semiconductor light emitting element is a light extraction surface. In this light emitting device, light emitted from the LED thin film portion of the semiconductor light emitting element is extracted without being blocked by the metal bumps or the like from the other surface side of the substrate, which is the light extraction surface side of the semiconductor light emitting element. Can increase the light output.

  As a semiconductor light emitting element that can be used in such a light emitting device, a semiconductor light emitting element in which the outer shape of the LED thin film portion is formed in the same rectangular shape as the outer shape on the one surface side of the substrate is illustrated in FIG. The semiconductor light emitting device 1 ′ is etched from the p-type nitride semiconductor layer 11 ′ of the LED thin film portion 1 b ′ to the center portion in plan view until the surface of the n-type nitride semiconductor layer 13 ′ of the LED thin film portion 1 b ′ is exposed by etching. A part of the p-type nitride semiconductor layer 11 ′ is removed. Metal bumps 4 ′ are formed on the surface side of the n-type nitride semiconductor layer 13 ′ exposed in a circular shape. Further, a semiconductor in which four metal bumps 3 ′ are provided on the surface of the p-type nitride semiconductor layer 11 ′ so as to surround one metal bump 4 ′ formed at the center of the LED thin film portion 1 b ′. A light emitting element 1 'has been proposed (for example, Patent Document 1).

  In addition, the semiconductor light emitting element 1 ′ is etched in the diagonal direction of the rectangular LED thin film portion 1b ′ from the central portion of the LED thin film portion 1b ′, whereby a part of the p-type nitride semiconductor layer 11 ′ is centered. It is removed diagonally from the part. Further, the n-type electrode 23 serving as the base of the metal bump 4 ′ is radially extended from the central portion on the surface of the n-type nitride semiconductor layer 13 ′ exposed by etching in the diagonal direction of the semiconductor light emitting device 1 ′. By providing the stretched portion 26, the current diffusibility to the p-type nitride semiconductor layer 11 ′ is enhanced.

Japanese Patent Laid-Open No. 2006-66868

  By the way, when it is going to use the light-emitting device which mounted the above-mentioned semiconductor light-emitting device 1 'on the mounting substrate as general lighting as an illumination light source, a large current of 1 A or more is applied to the semiconductor light-emitting device 1', for example, It is required to extract a large light output from the light emitting device. Therefore, in the semiconductor light emitting device 1 ′, the amount of heat generated in the LED thin film portion 1 b ′ of the semiconductor light emitting device 1 ′ increases when a large current flows. In this case, if the heat generated in the LED thin film portion 1b ′ of the semiconductor light emitting element 1 ′ cannot be efficiently radiated to the mounting substrate side through the metal bump 3 ′ and the metal bump 4 ′, the semiconductor light emitting element 1 ′. The light emission efficiency is reduced, and the light output is reduced. Furthermore, if the heat generated in the LED thin film portion 1b ′ of the semiconductor light emitting device 1 ′ cannot be efficiently radiated to the mounting substrate side through the metal bumps 3 ′ and 4 ′, the LED thin film portion 1b of the semiconductor light emitting device 1 ′. It is also conceivable that the heat distribution at 'is uneven and uneven brightness occurs in the surface of the LED thin film portion 1b'.

  Here, in the semiconductor light emitting device 1 ′, when the metal bump 4 ′ provided in the LED thin film portion 1 b ′, the n-type electrode 23, and the extending portion 26 of the n-type electrode 23 are to be enlarged in order to improve heat dissipation. Thus, the region where the p-type nitride semiconductor layer 11 ′ is etched increases, and the light emitting region of the LED thin film portion 1b ′ decreases. In addition, the shape of the LED thin film portion 1b ′ in the semiconductor light emitting element 1 ′ becomes distorted by the region etched in the central portion of the p-type nitride semiconductor layer 11 ′ in the plan view of the LED thin film portion 1b ′, and the semiconductor light emission It tends to be difficult to obtain a uniform output from the LED thin film portion 1b ′ of the element 1. Further, if the region to be etched on the p-type nitride semiconductor layer 11 ′ side in the LED thin film portion 1b ′ of the semiconductor light emitting device 1 ′ is reduced to increase the light emitting region, the metal bumps 3 ′, The cross-sectional area of the heat dissipation path that radiates heat to the mounting substrate via 4 'is reduced. For this reason, it is difficult to efficiently dissipate heat from the semiconductor light emitting element 1 ′ to the mounting substrate side through the metal bumps 3 ′ and 4 ′.

  Therefore, at the present time when a light emitting device having a higher light output as used in lighting applications is required, the above configuration is not sufficient, and further improvement in characteristics is required.

  This invention is made | formed in view of the said reason, The objective is to provide the light-emitting device which is excellent in heat dissipation and can aim at the improvement of a light output more.

  According to a first aspect of the present invention, there is provided a semiconductor light emitting device comprising a conductive substrate and an LED thin film portion formed on one surface side of the conductive substrate and having a p-type nitride semiconductor layer and an n-type nitride semiconductor layer, A mounting substrate on which the semiconductor light emitting element is mounted via a metal bump so that the other surface side of the conductive substrate of the semiconductor light emitting element is a light extraction surface. The LED thin film portion smaller than the conductive substrate is exposed so that the outer peripheral portion on the one surface side of the conductive substrate is exposed, and the metal bumps are formed on the outer peripheral portion of the conductive substrate. A plurality of first metal bumps provided so as to surround the LED thin film portion, and a plurality of second metal bumps provided on the surface side of the LED thin film portion facing the conductive substrate. I am characterized in.

  According to the present invention, the semiconductor light emitting device includes the LED thin film portion smaller than the conductive substrate so that the outer peripheral portion on the one surface side of the conductive substrate is exposed in a plan view, and the outer periphery of the conductive substrate. A plurality of first metal bumps provided so as to surround the LED thin film portion, and a plurality of second metal bumps provided on the surface side of the LED thin film portion facing the conductive substrate. It is possible to provide a light-emitting device that has a relatively simple configuration in which the semiconductor light-emitting element is mounted on a mounting substrate, has excellent heat dissipation, and can further improve light output.

  According to a second aspect of the invention, in the first aspect of the invention, the conductive substrate of the semiconductor light emitting device is a zinc oxide substrate, and the p-type nitride semiconductor layer in the LED thin film portion is replaced with the n-type nitride semiconductor. It is provided on the one surface side of the conductive substrate from the layer.

  According to the present invention, the zinc oxide substrate is provided with a p-type nitride semiconductor layer generally having a higher resistance than the n-type nitride semiconductor layer on the one surface side of the zinc oxide substrate. The substrate is configured such that current from a plurality of first metal pads provided on the outer peripheral portion of the zinc oxide substrate on the one surface side so as to surround the LED thin film portion is planarized in the p-type nitride semiconductor layer. Can be diffused. The heat generated in the LED thin film portion is transferred from the p-type nitride semiconductor layer of the LED thin film portion to the zinc oxide substrate in a planar shape, and the outer peripheral portion on the one surface side of the zinc oxide substrate. And diffused from a plurality of first metal pads provided so as to surround the LED thin film portion, and efficiently released to the mounting substrate side. Therefore, it is possible to obtain a light emitting device capable of improving the light output by making uniform the heat distribution in the LED thin film portion of the semiconductor light emitting element and suppressing the luminance unevenness.

  According to a third aspect of the present invention, in the first aspect of the invention, the conductive substrate of the semiconductor light emitting device is a nitride semiconductor substrate, and the n-type nitride semiconductor layer in the LED thin film portion is replaced with the p-type nitride. It is provided on the one surface side of the conductive substrate with respect to the semiconductor layer.

  According to the present invention, the p-type nitride semiconductor layer transfers the heat generated in the LED thin film portion to the mounting substrate side via the plurality of second metal pads provided on the p-type nitride semiconductor layer side. Heat can be dissipated. The heat generated in the LED thin film portion diffuses in a planar manner from the n-type nitride semiconductor layer to the nitride semiconductor substrate, and the LED thin film portion is formed on the outer peripheral portion on the one surface side of the nitride semiconductor substrate. Can be discharged through a plurality of first metal pads provided to surround the first metal pad. Therefore, a light emitting device capable of flowing a larger current and further improving the light output can be obtained.

  According to a first aspect of the present invention, a semiconductor light emitting device includes the LED thin film portion smaller than the conductive substrate so that an outer peripheral portion on one surface side of the conductive substrate is exposed in a plan view, Mounted by a plurality of first metal bumps provided on the outer periphery so as to surround the LED thin film part and a plurality of second metal bumps provided on the surface side of the LED thin film part facing the conductive substrate. By mounting on the substrate, there is an effect that the light emitting device is excellent in heat dissipation and can further improve the light output.

The light-emitting device of Embodiment 1 is shown, (a) is a schematic sectional drawing, (b) is a schematic plan view. It is a schematic plan view in a semiconductor light emitting element same as the above. It is a schematic plan view in a mounting board same as the above. The light-emitting device of Embodiment 2 is shown, (a) is a schematic sectional drawing, (b) is a schematic plan view. The schematic plan view in a semiconductor light emitting element same as the above is shown. The schematic plan view in the mounting board same as the above is shown. It is a schematic plan view in the conventional semiconductor light-emitting device.

(Embodiment 1)
Hereinafter, the light-emitting device of this embodiment will be described with reference to FIGS. 1 to 3.

  As shown in FIG. 1, the light emitting device 20 of this embodiment includes a zinc oxide substrate 1a as a conductive substrate and a p-type nitride semiconductor layer 11 and an n-type nitride semiconductor formed on one surface side of the zinc oxide substrate 1a. Semiconductor light emitting device 1 having LED thin film portion 1b having layer 13 and semiconductor light emission via metal bumps 3 and 4 so that the other surface side of zinc oxide substrate 1a of semiconductor light emitting device 1 is a light extraction surface. And a mounting substrate 2 on which the element 1 is mounted.

  In particular, the semiconductor light emitting element 1 used in the light emitting device 20 has an LED thin film portion 1b smaller than the zinc oxide substrate 1a so that the outer peripheral portion 1d on the one surface side of the zinc oxide substrate 1a is exposed in a plan view shown in FIG. It has. The metal bumps 3 and 4 used in the light emitting device 20 include a plurality of p-type electrode pads 5 provided on the outer peripheral portion 1d of the zinc oxide substrate 1a so as to surround the LED thin film portion 1b, and the LED thin film portion 1b. Are connected to a plurality of n-type electrode pads 6 provided on the surface side facing the zinc oxide substrate 1a. More specifically, the plurality of p-type electrode pads 5 are connected to the mounting substrate 2 side via a plurality of first metal bumps 3 that are bonded one-on-one. Further, the plurality of n-type electrode pads 6 are connected to the mounting substrate 2 side via a plurality of second metal bumps 4 that are bonded one-on-one.

  Thereby, the heat generated in the LED thin film portion 1b of the semiconductor light emitting element 1 is transferred from the p-type nitride semiconductor layer 11 of the LED thin film portion 1b to the zinc oxide substrate 1a in a planar shape. The heat transferred to the zinc oxide substrate 1a is connected to the p-type electrode pad 5 and the p-type electrode pad 5 provided on the outer peripheral portion 1d on the one surface of the zinc oxide substrate 1a so as to surround the LED thin film portion 1b. The heat can be radiated to the mounting substrate 2 via the first metal bump 3. Similarly, the heat generated in the LED thin film portion 1b of the semiconductor light emitting element 1 is also supplied from the n-type nitride semiconductor layer 13 in the LED thin film portion 1b to the n-type electrode pad 6 and the n-type electrode pad 6. Heat can be radiated to the mounting substrate 2 side through the metal bumps 4.

  Hereinafter, each structure used for the light-emitting device 20 of this embodiment is demonstrated. First, the semiconductor light emitting device 1 will be described in detail.

  The semiconductor light emitting device 1 includes an LED thin film portion 1b having a p-type nitride semiconductor layer 11 and an n-type nitride semiconductor layer 13 on one surface of a zinc oxide substrate 1a that is a conductive substrate, and the one surface of the zinc oxide substrate 1a. The other surface side opposite to is used as a light extraction surface.

  Therefore, the conductive substrate of the semiconductor light emitting element 1 is translucent to the wavelength of light emitted from the LED thin film portion 1b of the semiconductor light emitting element 1, and supplies power to the LED thin film portion 1b. It has possible conductivity. Examples of the material of the conductive substrate include a zinc oxide substrate 1a made of an n-type ZnO material.

  In this embodiment, the zinc oxide substrate 1a is used as the conductive substrate of the semiconductor light emitting element 1, and the outer shape of the zinc oxide substrate 1a is a hexagonal pyramid shape having the LED thin film portion 1b on the bottom surface. Such a hexagonal pyramid outer shape of the zinc oxide substrate 1a uses, for example, crystal anisotropic etching utilizing the crystal orientation dependence of the etching rate by immersing the other surface side of the zinc oxide substrate 1a in hydrochloric acid. Can be formed. The outer shape of the zinc oxide substrate 1a can be formed in a hexagonal truncated pyramid shape by adjusting the etching time. Thus, the light extraction efficiency from the semiconductor light-emitting element 1 can be further improved by forming the other surface side of the zinc oxide substrate 1a serving as the light extraction surface of the semiconductor light-emitting element 1 into a hexagonal pyramid shape or a hexagonal truncated cone shape. Can do. The outer shape of the zinc oxide substrate 1a is not limited to the hexagonal pyramid shape or the hexagonal truncated pyramid shape, and may be a cubic shape or a rectangular parallelepiped shape.

  The LED thin film portion 1 b of the semiconductor light emitting device 1 includes a p-type nitride semiconductor layer 11 formed on the one surface of the zinc oxide substrate 1 a and an n-type nitride semiconductor layer 13 on the p-type nitride semiconductor layer 11. The laminated structure can radiate blue light. Further, the LED thin film portion 1b of the semiconductor light emitting element 1 has a hexagonal shape on the one surface of the zinc oxide substrate 1a so that the outer peripheral portion 1d on the one surface side of the zinc oxide substrate 1a is exposed in a plan view shown in FIG. Is formed in a smaller hexagonal shape, similar to the zinc oxide substrate 1a.

  Further, in the semiconductor light emitting device 1 of the present embodiment, the p-type electrode pad 5 is formed in ohmic contact with the zinc oxide substrate 1a at the outer peripheral portion 1d on the one surface of the zinc oxide substrate 1a. . Thereby, the p-type nitride semiconductor layer 11 in the LED thin film portion 1b of the semiconductor light emitting element 1 can be electrically connected from the p-type electrode pad 5 through the zinc oxide substrate 1a. Further, in the semiconductor light emitting device 1, an n-type electrode pad 6 is formed on the surface of the n-type nitride semiconductor layer 13 so as to be in ohmic contact with the n-type nitride semiconductor layer 13 of the LED thin film portion 1b. As a result, the n-type nitride semiconductor layer 13 in the LED thin film portion 1 b of the semiconductor light emitting device 1 is electrically connected to the n-type electrode pad 6. Here, 19 n-type electrode pads 1 c are arranged on the surface of the n-type nitride semiconductor layer 13 so as to be radially spaced from the center of the n-type nitride semiconductor layer 13. Further, on the outer peripheral portion 1d of the zinc oxide substrate 1a, eleven p-type electrode pads 5 are arranged so as to surround the LED thin film portion 1b at substantially equal intervals except for one side of the hexagon.

  Here, the p-type electrode pad 5 and the n-type electrode pad 6 are preferably provided in order to improve the adhesion with the first metal bump 3 and the second metal bump 4, respectively. The p-type electrode pad 5 and the zinc oxide substrate 1a may be directly joined or may be connected via a p-type electrode. Similarly, the n-type electrode pad 6 and the n-type nitride semiconductor layer 13 may be directly joined or may be connected via an n-type electrode. By making the size of the p-type electrode and the n-type electrode larger than those of the p-type electrode pad 5 and the n-type electrode pad 6, respectively, current diffusibility and heat dissipation can be further improved. For example, the p-type electrode may be formed in a ring shape along the outer peripheral portion 1d of the zinc oxide substrate 1a. The n-type electrode may be formed on the entire surface of the n-type nitride semiconductor layer 13 (not shown).

  As a more detailed configuration of the LED thin film portion 1b used in the semiconductor light emitting device 1 of the present embodiment, the light emitting layer 12 is sandwiched between the n-type nitride semiconductor layer 13 and the p-type nitride semiconductor layer 11 and formed in a laminated structure. is doing.

  The n-type nitride semiconductor layer 13 of the LED thin film portion 1b is composed of an n-type GaN layer that functions as a cladding layer for the light emitting layer 12 and also functions as a contact layer. The n-type nitride semiconductor layer 13 is not limited to a single layer structure, and may be a multilayer structure in which an n-type GaN layer functioning as a contact layer and an n-type InGaN layer functioning as a cladding layer are functionally separated. .

  Further, in order to function as a clad layer or a contact layer, each layer is not limited to a single layer structure, but may be formed in a multilayer structure. For example, in order to reduce the internal stress generated in the LED thin film portion 1b and improve the crystallinity, the cladding layer and the contact layer are not only formed with a single-layer structure having a thick film, but also nitrides having different compositions. The semiconductor layer can also be formed of a superlattice multilayer film having a quantum effect in which thin layers having a thickness of several to hundreds of layers are alternately stacked. Examples of such a superlattice multilayer film include a laminated film in which InGaN layers and GaN layers are alternately laminated in a thin film, and a laminated film in which AlGaN layers and GaN layers are alternately laminated in a thin film. The superlattice multilayer film has electric and optical characteristics different from those of the single-layer structure while reducing the internal stress generated in the LED thin film portion 1b by adjusting the composition, film thickness, and number of layers. Can be made.

  The light emitting layer 12 in the LED thin film portion 1b of the present embodiment has a multiple quantum well structure in which a well layer made of an InGaN layer is sandwiched between barrier layers made of a GaN layer. In the light emitting layer 12, the In composition ratio of the InGaN layer is set so that the emission peak of emitted light is 460 nm, but the emission peak is not particularly limited. The light emitting layer 12 of the semiconductor light emitting device 1 is not limited to a multiple quantum well structure, and may be a single quantum well structure. The light emitting layer 12 may be formed with a homo structure, a hetero structure, or a double hetero structure. The material of the light emitting layer 12 may be a nitride semiconductor material. For example, in addition to AlGaInN, AlInN, and AlGaN, GaN containing Si and Zn may be used.

  The p-type nitride semiconductor layer 11 of the LED thin film portion 1b includes a first p-type nitride semiconductor layer composed of a p-type AlGaN layer that functions as a cladding layer with respect to the light emitting layer 12, and p-type GaN that functions as a contact layer. The second p-type nitride semiconductor layer made of layers is functionally separated. The p-type nitride semiconductor layer 11 may have a multilayer structure or a single-layer structure consisting of only a p-type GaN layer or a p-type AlGaN layer, depending on mass productivity and required electrical characteristics and optical characteristics. Further, as in the case of the n-type nitride semiconductor layer 13, the cladding layer and the contact layer of the p-type nitride semiconductor layer 11 are not only formed with a thick single-layer structure, but also have different compositions. You may form with the superlattice multilayer film said to show the quantum effect which laminated | stacked the nitride semiconductor layer by the film thickness of several to several hundreds of turns alternately.

  The LED thin film portion 1b is formed on the main surface side of the sapphire wafer whose main surface is the (0001) plane before the LED thin film portion 1b is bonded to the n-type ZnO wafer serving as the basis of the zinc oxide substrate 1a. In addition, an n-type nitride semiconductor layer 13, a light emitting layer 12, and a p-type nitride semiconductor layer 11 are sequentially formed through a low temperature growth buffer layer (for example, a GaN layer, an AlN layer, an AlGaN layer, etc.). The film can be formed using an epitaxial growth technique such as Here, the epitaxial growth method of the LED thin film portion 1b is not limited to the MOVPE method. Also good.

  By the way, both the nitride semiconductor material and the zinc oxide material are polar semiconductors having a wurtzite crystal structure and polarity in the c-axis direction. Therefore, the LED thin film portion 1b is configured by a (000-1) plane in which the surface of the n-type nitride semiconductor layer 13 opposite to the light emitting layer 12 side of the n-type GaN layer is an N-polar plane, and is p-type. The surface of the nitride semiconductor layer 11 opposite to the light emitting layer 12 side of the p-type GaN layer is constituted by a (0001) plane that is a Ga polar plane. In addition, the zinc oxide substrate 1a includes the LED thin film portion 1b, and the one surface side is constituted by a (0001) plane that is a Zn polar plane, and the other surface side of the zinc oxide substrate 1a is an O polar plane (000-1). It is composed of surfaces.

  That is, the LED thin film portion 1b and the zinc oxide substrate 1a are joined to the Zn polar surface of the zinc oxide substrate 1a and the Ga polar surface of the p-type nitride semiconductor layer 11.

  The zinc oxide substrate 1a may be a non-doped ZnO substrate that exhibits n-type conductivity due to oxygen vacancies or zinc interstitial defects without doping impurities, but the conductivity type and conductivity can be increased by doping impurities. It may be controlled. Examples of the zinc oxide substrate 1a whose conductivity type and conductivity are controlled by doping impurities include a Ga-doped ZnO substrate (GZO substrate) and an Al-doped ZnO substrate (AZO substrate). The zinc oxide substrate 1a, whose conductivity type and conductivity are controlled by doping impurities, is in ohmic contact with the p-type electrode pad 5 etc. that is in contact with the zinc oxide substrate 1a, as compared with the zinc oxide substrate 1a not doped with impurities. It is more preferable because the contact resistance can be reduced.

  Next, the p-type electrode pad 5 provided around the LED thin film portion 1b on the outer peripheral portion 1d of the zinc oxide substrate 1a of the semiconductor light emitting element 1 and the n-type provided on the surface of the n-type nitride semiconductor layer 13 in the LED thin film portion 1b. The electrode pad 6 is composed of a laminated film of a Ti film, an Al film, and an Au film, respectively. Each of the p-type electrode pad 5 and the n-type electrode pad 6 is composed of an Au film on the outermost surface side. Here, the p-type electrode pad 5 and the n-type electrode pad 6 can have, for example, a Ti film thickness of 10 nm, an Al film thickness of 50 nm, and an Au film thickness of 500 nm. The numerical value is an example and is not particularly limited. Further, if necessary, between the p-type electrode pad 5 and the zinc oxide substrate 1 a and between the n-type electrode pad 6 and the n-type nitride semiconductor layer 13, separately for current diffusion, thermal diffusion, and the like. An electrode may be formed.

  In any case, in the semiconductor light emitting device 1 of this embodiment, the p-type electrode pad 5 and the n-type electrode pad 6 are formed of the same metal material and have the same electrode structure. The p-type electrode pad 5 and the n-type electrode pad 6 can enhance the adhesion between the films that overlap each other in the thickness direction in the laminated film constituting each of the p-type electrode pad 5 and the n-type electrode pad 6. The adhesion to the semiconductor layer 13 can also be improved. Further, the p-type electrode pad 5 and the n-type electrode pad 6 can be simultaneously formed with high productivity by the structure of the laminated film. Here, the p-type electrode pad 5 and the n-type electrode pad 6 are simultaneously formed by an electron beam vapor deposition method (EB vapor deposition method). However, the present invention is not limited to this, and sputtering or other vapor deposition methods ( For example, it may be formed using resistance heating vapor deposition or induction heating vapor deposition).

  In the semiconductor light emitting device 1 of this embodiment, the outer peripheral portion 1d of the zinc oxide substrate 1a is formed by adopting a laminated film of a Ti film, an Al film, and an Au film as the p-type electrode pad 5 and the n-type electrode pad 6. Good ohmic contact (low ohmic resistance ohmic contact) can be obtained with respect to the surface of the n-type nitride semiconductor layer 13, respectively. The p-type electrode pad 5 and the n-type electrode pad 6 are not limited to the laminated film, but are a laminated film of a Ti film and an Au film, a laminated film of an Al film and an Au film, a Ti film, an Al film, and a Ni film. And a single laminated film selected from the group of laminated films of Au and Au films. In any configuration, the outermost surfaces of the p-type electrode pad 5 and the n-type electrode pad 6 are made of an Au film, so that oxidation of the surfaces of the p-type electrode pad 5 and the n-type electrode pad 6 can be prevented. The p-type electrode pad 5 and the n-type electrode pad 6 provided on the semiconductor light emitting device 1 are respectively a first metal bump (for example, Au bump) 3 and a second metal bump (for example, Au bump). 4 can be mounted on the wiring pads 21 and 22 provided on the wiring patterns 8 and 9 of the mounting substrate 2.

  In addition, the semiconductor light emitting device 1 of the present embodiment may have a fine concavo-convex structure on the surface of the n-type nitride semiconductor layer 13 opposite to the zinc oxide substrate 1a side in the LED thin film portion 1b. The fine concavo-convex structure can improve the light extraction efficiency of the semiconductor light emitting device 1 by scattering light emitted from the LED thin film portion 1b. Further, when a fine concavo-convex structure is formed at the formation site of the n-type electrode pad 6 on the surface of the n-type nitride semiconductor layer 13, the adhesion between the surface of the n-type nitride semiconductor layer 13 and the n-type electrode pad 6 is improved. Can be made. In addition, the period and height difference of the fine concavo-convex structure may be appropriately set to several μm or less.

  In the present embodiment, the light emitted from the p-type nitride semiconductor layer 11 to the zinc oxide substrate 1a side in the LED thin film portion 1b of the semiconductor light emitting element 1 is the refractive index of the nitride semiconductor material and the zinc oxide material. Since the difference is smaller than the refractive index difference between the nitride semiconductor material and sapphire used for general blue LED elements, light is efficiently emitted from the LED thin film portion 1b of the semiconductor light emitting element 1 to the zinc oxide substrate 1a side. It can be taken out.

  In addition, the outer peripheral portion 1d on the one surface side of the zinc oxide substrate 1a may have a concavo-convex structure in order to improve the adhesion with the p-type electrode pad 5. Such a concavo-convex structure of the outer peripheral portion 1d can be appropriately designed such as a desired period and a height difference.

  Hereinafter, a method for manufacturing the semiconductor light emitting element 1 used in the light emitting device 20 of the present embodiment will be described.

  The semiconductor light-emitting device 1 includes an n-type nitride semiconductor layer 13, a light-emitting layer 12, and a p-type nitride that become the LED thin film portion 1 b through an AlGaN layer that becomes a low-temperature growth buffer layer on the main surface side that is the C-plane of the sapphire wafer A stacked structure film with the semiconductor layer 11 is sequentially formed by a crystal growth method such as the MOVPE method. On the other hand, an n-type ZnO wafer formed by a hydrothermal synthesis method or the like is used as the basis of the zinc oxide substrate 1 a of the semiconductor light emitting device 1. Next, in order to form the LED thin film portion 1b on the zinc oxide substrate 1a, after cleaning the bonding surface between the main structure side of the sapphire wafer and the n-type ZnO wafer, in a nitrogen atmosphere And heated to 600 ° C. and thermally bonded by applying a pressure of 2 MPa. Thereafter, the sapphire wafer is peeled off from the wafer in which the sapphire wafer and the n-type ZnO wafer are thermally bonded to form a wafer in which the laminated structure film to be the LED thin film portion 1b is thermally bonded on the n-type ZnO wafer. Can be made.

  Here, the sapphire wafer is peeled off by, for example, irradiating a laser beam near the interface between the sapphire wafer and the laminated structure film and forming the low-temperature growth buffer layer by a laser processing step together with the laminated structure film. There is a method to peel off. As another method for peeling off the sapphire wafer, the laminated structure film is crystal-grown on the sapphire wafer by selective growth, and after thermal bonding with the n-type ZnO wafer, the laminated structure film, the sapphire wafer, And a method of peeling the sapphire wafer side by thermal stress using a void formed during selective growth in the vicinity of the interface.

  Next, patterning is performed on the n-type ZnO wafer so that the outer peripheral portion 1d of the one surface of the zinc oxide substrate 1a is exposed by using a photolithography technique and an etching technique, and a hexagonal prism-shaped LED is formed. The thin film portion 1b is formed.

  Thereafter, a Ti film is formed on the n-type ZnO wafer corresponding to the outer peripheral portion 1d of the zinc oxide substrate 1a by using a film formation by electron beam evaporation, photolithography technique and etching technique on the one surface side of the zinc oxide substrate 1a. Then, an Al film and a p-type electrode pad 5 whose outermost surface is an Au film are formed. At the same time, the Ti film, the Al film, and the n-type electrode pad 6 whose outermost surface is an Au film are formed on the n-type GaN layer functioning as the contact layer of the n-type nitride semiconductor layer 13 in the LED thin film portion 1b.

  Subsequently, a mask layer is formed in which a mask layer patterned corresponding to each LED thin film portion 1b is formed on the other surface opposite to the one surface where the plurality of LED thin film portions 1b are formed in the n-type ZnO wafer. Perform the process. Then, after performing crystal anisotropic etching using the crystal orientation dependency of the etching rate using a hydrochloric acid-based etching solution (for example, hydrochloric acid aqueous solution), the mask layer is removed. Thereby, the semiconductor light-emitting device 1 having a hexagonal pyramid-shaped zinc oxide substrate 1a having a smooth etching surface and a height from the bottom surface having the LED thin film portion 1b to the apex of about 500 μm can be formed. .

  Next, the mounting substrate 2 used in the light emitting device 20 of the present embodiment will be described. As shown in FIG. 1, the mounting substrate 2 has a base portion 7 made of an AlN material having a substantially rectangular parallelepiped shape, and an electric current is supplied to the semiconductor light emitting element 1 disposed on the surface of the base portion 7. A pair of wiring patterns 8 and 9 made of a possible Au film are formed.

  One wiring pattern 9 includes a hexagonal portion 15 at the center of the rectangular surface of the base portion 7 in plan view as shown in FIG. Further, the wiring pattern 9 has a wiring extending from one central end on one side of the hexagonal shape portion 15 toward one corner of the rectangular shape on the surface of the base portion 7, and a substantially circular land on the other end of the wiring. Is forming. A pad electrode 17 made of an Au film serving as a cathode electrode is formed on the land so as to be electrically connected to the outside of the light emitting device 20. The other wiring pattern 8 includes a ring-shaped portion 14 that surrounds the hexagonal portion 15 of the one wiring pattern 9 so as to be separated from the outer periphery. A part of the ring-shaped portion 14 is cut out so as not to be short-circuited with the wiring of one wiring pattern 9.

  The other wiring pattern 8 is wired from one end of the ring-shaped portion 14 on the other side facing the one side of the hexagonal portion 15 toward the corner on the surface of the base portion 7 facing the one corner. And a substantially circular land is formed at the other end of the wiring. A pad electrode 16 made of an Au film serving as an anode electrode is formed on the land so as to be electrically connected to the outside of the light emitting device 20. Further, a light reflecting film 18 that covers the one surface of the base portion 7 and reflects light from the semiconductor light emitting element 1 is formed so as to be electrically separated from the wiring patterns 8 and 9.

  Furthermore, eleven first wiring pads 21 connected to the first metal bumps 3 for mounting the semiconductor light emitting element 1 on a one-to-one basis on the ring-shaped portion 14 in the wiring pattern 8 of the mounting substrate 2. Forming. Similarly, 19 second wiring pads 22 connected to the second metal bump 4 for mounting the semiconductor light emitting element 1 on the hexagonal portion 15 in the wiring pattern 9 of the mounting substrate 2 in a one-to-one manner. Is forming. Here, the semiconductor light emitting element 1 is formed on the wiring patterns 8 and 9 of the mounting substrate 2 with the other surface side facing the one surface side provided with the LED thin film portion 1b of the zinc oxide substrate 1a as the light extraction surface side. Mounting is performed via one metal bump 3 and second metal bump 4.

  The base portion 7 of the mounting substrate 2 is preferably made of a material having high thermal conductivity so that heat from the LED thin film portion 1b of the semiconductor light emitting element 1 can be efficiently radiated to the mounting substrate 2 side through the metal bumps 3 and 4. . Specific examples of the material for the base portion 7 include alumina, aluminum nitride, and metal Cu. In the case where the base portion 7 has conductivity such as metal Cu, an insulating film (for example, a crystal) is used so as not to disturb the thermal conductivity to the base portion 7 between the surface of the base portion 7 and the wiring patterns 8 and 9. (Such as glass or metal oxide) may be formed separately. The wiring patterns 8 and 9 can be formed of, for example, an Au film.

  In the present embodiment, on the wiring patterns 8 and 9 of the mounting substrate 2, a first wiring pad 21 that can be connected to the first metal bump 3 and a second wiring that can be connected to the second metal bump 4. Pad 22 is formed. Here, the first wiring pad 21 of the wiring pattern 8 is electrically connected via the p-type electrode pad 5 and the first metal bump 3 provided on the one surface of the zinc oxide substrate 1 a in the semiconductor light emitting device 1. Connected. Further, the second wiring pad 22 of the wiring pattern 9 is connected to the n-type electrode pad 6 provided on the n-type nitride semiconductor layer 13 of the LED thin film portion 1 b in the semiconductor light emitting device 1 and the second metal bump 4. It is electrically connected.

  The light reflecting film 18 of the mounting substrate 2 of the present embodiment reflects light emitted from the LED thin film portion 1b of the semiconductor light emitting element 1 to the light extraction surface side, and reflects light emitted from the semiconductor light emitting element 1. In contrast, a metal film having a high reflectance may be used. Therefore, although depending on the wavelength of light emitted from the semiconductor light emitting device 1, a metal material such as Ag or Al can be used as the material of the light reflecting film 18, for example. Thereby, it can suppress that the light radiated | emitted from the LED thin film part 1b of the semiconductor light-emitting element 1 to the mounting substrate 2 side is absorbed by the mounting substrate 2, and the light output fall of the light-emitting device 20 can be prevented.

  Here, the light reflection film 18 is not limited to a single-layer film of an Ag film, and may be a multilayer film of an Ag film and an Au film, for example. The light reflecting film 18 may be formed by, for example, electrolytic plating, sputtering, or electron beam evaporation.

  Next, each metal bump 3, 4 used in the light emitting device 20 of the present embodiment is for mounting and fixing the semiconductor light emitting element 1 on the mounting substrate 2, and is formed of an Au film. The material of the metal bumps 3 and 4 is not limited to Au, and AuSn or SnAgCu may be used. Moreover, each metal bump 3 and 4 can be formed in multiple numbers, respectively, and the number is not limited. However, at least three first metal bumps 3 are provided so as to surround the LED thin film portion 1b.

  The metal bumps 3 and 4 may be formed in advance on the p-type electrode pad 5 and the n-type electrode pad 6 of the semiconductor light-emitting element 1 before the semiconductor light-emitting element 1 is mounted on the mounting substrate 2. It may be formed in advance on the first wiring pad 21 or the second wiring pad 22 of the substrate 2. Further, each metal bump 3, 4 is formed by forming a p-type electrode pad 5 or an n-type electrode pad 6 with a thick film, and each metal bump 3, 4, p-type electrode pad 5, n-type electrode pad 6, May also be used. Similarly, the metal bumps 3 and 4 are formed by forming the first wiring pads 21 and the second wiring pads 22 in a thick film, and the metal bumps 3 and 4 and the first wiring pads 21 and the second wiring pads 22 are formed. The wiring pad 22 can also be used.

  In order to form each of the metal bumps 3 and 4, an electrolytic plating method, a stud bump method, a printing method, a vapor deposition method, or the like may be used. The metal bumps 3 and 4 are made of the same material for the first metal bump 3 connected to the p-type electrode pad 5 and the second metal bump 4 connected to the n-type electrode pad 6 in order to improve mass productivity. May be used simultaneously. Each metal bump 3, 4 is a second metal that connects the first metal bump 3 connected to the outer peripheral portion 1 d of the zinc oxide substrate 1 a by the thickness of the LED thin film portion 1 b to the n-type nitride semiconductor layer 13. You may form with another structure made thicker than the bump 4, and another material.

  Specifically, a resist film having an opening portion that opens on the first wiring pad 21 and the second wiring pad 22 is formed in advance on the surface side of the mounting substrate 2 by using a photolithography technique. Next, after an Au film is grown on the opening by an electrolytic plating method, the resist film is removed to form an Au film as a material for the metal bumps. Subsequently, a protective mask is formed on the surface side of the mounting substrate 2 except for the Au film by using a photolithography technique, and the mounting substrate 2 is reflowed to melt the Au film so that each spherical metal bump is formed. 3 and 4 can be formed on the wiring pads 21 and 22, respectively. Finally, the mounting mask 2 provided with the metal bumps 3 and 4 can be formed by removing the protective mask.

  Each metal bump 3, 4 is formed larger by one each for the first metal bump 3 and the second metal bump 4 even if they are bonded to the semiconductor light emitting element 1 and the mounting substrate 2 with the same bonding area. Rather than making the first metal bumps 3 and the second metal bumps 4 smaller in size, the current distribution to the semiconductor light emitting element 1 and the heat distribution from the semiconductor light emitting element 1 are adjusted. Cheap. Further, when the semiconductor light emitting element 1 is mounted on the mounting substrate 2 through the metal bumps 3 and 4, a plurality of first metal bumps 3 and a plurality of second metal bumps 4 formed separately are used. The mounting is easier to achieve with higher mounting accuracy and stronger mounting than mounting with the first metal bumps 3 and the second metal bumps 4 one by one.

  Next, the semiconductor light emitting element 1 is mounted on the mounting substrate 2 via the first metal bump 3 and the second metal bump 4 to manufacture the light emitting device 20 of the present embodiment.

  The semiconductor light emitting device 1 is mounted on the mounting substrate 2 with the other surface side facing the one surface side where the LED thin film portion 1b of the zinc oxide substrate 1a is provided as the light extraction surface side.

  Here, the p-type electrode pad 5 and the n-type electrode pad 6 of the semiconductor light emitting device 1 and the first metal bump 3 and the wiring pattern 9 formed on the wiring pattern 8 on the mounting substrate 2 are formed. The second metal bumps 4 are aligned and mounted by thermocompression bonding. When current is supplied from the outside between the pad electrode 16 provided on the wiring pattern 8 and the pad electrode 17 provided on the wiring pattern 9 on the mounting substrate 2 of the light-emitting device 20 formed in this way, the light-emitting device 20 causes the blue light to emit light. Can emit light.

Here, the thermal conductivity of the zinc oxide material used for the zinc oxide substrate 1a of the semiconductor light emitting device 1 is about 0.6 W / cmK, and a blue LED device using a generally known nitride semiconductor or the like. Compared with about 0.3 W / cmK of the thermal conductivity of sapphire (Al ₂ O ₃ ), which is a substrate material, the thermal conductivity is about twice as excellent. Therefore, in the light emitting device 20 of the present embodiment, the heat of the LED thin film portion 1b of the semiconductor light emitting device 1 is heated from the p-type nitride semiconductor layer 11 in the LED thin film portion 1b to the zinc oxide substrate 1a of the semiconductor light emitting device 1 in a planar shape. Can conduct. The heat of the thermally conductive zinc oxide substrate 1a can be radiated from the outer peripheral portion 1d on the one surface of the zinc oxide substrate 1a to the mounting substrate 2 side through the first metal bump 3 surrounding the LED thin film portion 1b. . Similarly, the heat of the LED thin film portion 1 b of the semiconductor light emitting element 1 can be radiated from the n-type nitride semiconductor layer 21 of the LED thin film portion 1 b to the mounting substrate 2 through the second metal bump 4. Thereby, it can be set as the light-emitting device 20 which is excellent in heat dissipation and can aim at the improvement of a light output more.

  In the present embodiment, the light emitting layer 12 is designed so that the light emitted from the semiconductor light emitting element 1 becomes blue light. However, the light emitted from the semiconductor light emitting element 1 is limited to blue light. For example, it may be ultraviolet light, green light, yellow light, or the like.

  In addition, the light emitting device 20 emits mixed color light such as white by providing a cover of a wavelength conversion member containing a phosphor that absorbs light from the semiconductor light emitting element 1 and converts the wavelength on the mounting substrate 2. It can also be made. Furthermore, the light emitting device 20 can mount a plurality of semiconductor light emitting elements 1 on the mounting substrate 2 as desired, and uses the wiring patterns 8 and 9 provided with the semiconductor light emitting elements 1 on the mounting substrate 2. It may be electrically connected in series, in parallel, or in series-parallel.

(Embodiment 2)
The basic configuration of the light emitting device 20 of the present embodiment is substantially the same as that of the first embodiment, and the p-type nitride semiconductor layer 11 in the LED thin film portion 1b of the semiconductor light emitting element 1 is provided on one surface side of the zinc oxide substrate 1a. Instead, as shown in FIG. 4, the difference is that the n-type nitride semiconductor layer 13 in the LED thin film portion 1b of the semiconductor light emitting device 1 is provided on one surface side of the nitride semiconductor substrate 1c made of n-type GaN material. In addition, the same code | symbol is attached | subjected to the component similar to Embodiment 1, and description is abbreviate | omitted suitably.

  In the light emitting device 20 of the present embodiment, the semiconductor light emitting element 1 is a first light extraction surface on the other surface side facing the one surface side where the LED thin film portion 1b of the nitride semiconductor substrate 1c of the semiconductor light emitting element 1 is provided. It is mounted on the mounting substrate 2 side through one metal bump 3 and second metal bump 4.

  In the semiconductor light emitting device 1 of this embodiment, an LED thin film portion 1b is formed in contact with one surface of a nitride semiconductor substrate 1c that is a conductive substrate. The LED thin film portion 1b in the semiconductor light emitting device 1 of the present embodiment is substantially the same as the stacked structure of the LED thin film portion 1b in Embodiment 1, but the n-type nitride semiconductor layer 13 in the LED thin film portion 1b is replaced with a p-type nitride. It is provided on the one surface side of the nitride semiconductor substrate 1c, which is a conductive substrate, with respect to the semiconductor layer 11. Here, the LED thin film portion 1b of the semiconductor light emitting device 1 has the one surface of the nitride semiconductor substrate 1c so that the outer peripheral portion 1d on the one surface side of the nitride semiconductor substrate 1c is exposed in a plan view shown in FIG. Is formed in a substantially rectangular shape that is substantially similar to and smaller than the nitride semiconductor substrate 1c at the center of the rectangular shape. The substantially rectangular shape of the LED thin film portion 1b is formed by cutting out four corners. In addition, a p-type electrode 19 having a substantially rectangular shape smaller than that of the p-type nitride semiconductor layer 11 is formed on the entire surface of the p-type nitride semiconductor layer 11 in the LED thin film portion 1b. Here, the p-type electrode 19 is a laminated structure of a Pt film, an Ag film, a Ni film, and an Au film. The p-type electrode 19 has an Au film on the outermost surface side.

  In the semiconductor light emitting device 1, four n-type electrode pads 6 are formed so as to surround the LED thin film portion 1b at the four corners of the outer peripheral portion 1d on the one surface side of the nitride semiconductor substrate 1c. The n-type electrode pad 6 is a laminated structure of a Ti film, an Al film, and an Au film. The n-type electrode pad 6 has an Au film on the outermost surface side.

  Further, the mounting substrate 2 of the present embodiment has a pair of wiring patterns 8 and 9 in consideration of the arrangement shape of the n-type electrode pad 6 and the p-type electrode 19 on the one surface side of the semiconductor light emitting element 1 on the base portion 7. Is forming. One wiring pattern 8 includes a rectangular portion 24 that is inclined at approximately 45 degrees with respect to the rectangle of the base portion 7 at the center of the rectangular surface of the base portion 7 in a plan view shown in FIG. Further, the wiring pattern 8 has a wiring extending from one central end of one side of the rectangular portion 24 toward one corner of the rectangular shape on the surface of the base portion 7, and a substantially circular land at the other end of the wiring. Is forming. A pad electrode 16 made of an Au film serving as an anode electrode is formed on the land so as to be electrically connected to the outside of the light emitting device 20. In addition, the other wiring pattern 9 includes a ring-shaped portion 25 that surrounds and is separated along the outer periphery of the rectangular-shaped portion 24 in the one wiring pattern 8.

  The other wiring pattern 9 is directed from one end of the ring-shaped portion 25 on the other side facing the one side of the rectangular portion 24 toward the corner on the one surface of the base portion 7 facing the one corner. The wiring extends, and a substantially circular land is formed at the other end of the wiring. A pad electrode 17 made of an Au film serving as a cathode electrode is formed on the land so as to be electrically connected to the outside of the light emitting device 20.

  In this embodiment, the n-type electrode pads 6 formed at the four corners so as to surround the substantially rectangular LED thin film portion 1b on the outer peripheral portion 1d of the one surface of the nitride semiconductor substrate 1c of the semiconductor light emitting device 1 are mounted substrates. The second wiring pattern 9 and the first metal bump 3 are electrically connected. Similarly, the plurality of p-type electrode pads 5 formed on the p-type electrode 19 formed on the surface of the LED thin film portion 1 b are electrically connected via the wiring pattern 8 and the second metal bump 4 of the mounting substrate 2. Will be connected to. Note that a plurality of p-type electrode pads 5 having the same configuration and the same material as the n-type electrode pad 6 are formed on the p-type electrode 19 in order to be connected to the second metal bump 4 on a one-to-one basis.

  Therefore, the semiconductor light emitting device 1 is formed on the wiring patterns 8 and 9 of the mounting substrate 2 with the other surface side facing the one surface side provided with the LED thin film portion 1b of the nitride semiconductor substrate 1c as the light extraction surface side. The first metal bump 3 and the second metal bump 4 are mounted.

  Here, the thermal conductivity of GaN used for the nitride semiconductor substrate 1c of the semiconductor light emitting device 1 is about 1.3 W / cmK, which is about 4 compared with about 0.3 W / cmK of sapphire. Twice as large. Therefore, in the light emitting device 20 of this embodiment, the heat of the LED thin film portion 1b of the semiconductor light emitting element 1 is transferred from the n-type nitride semiconductor layer 13 in the LED thin film portion 1b to the nitride semiconductor substrate 1c of the semiconductor light emitting element 1 in a planar shape. It can conduct heat. The heat conducted to the nitride semiconductor substrate 1c is transmitted from the n-type electrode pads 6 formed at the four corners so as to surround the substantially rectangular LED thin film portion 1b on the outer peripheral portion 1d on one surface of the nitride semiconductor substrate 1c. Heat can be radiated to the mounting substrate 2 side through one metal bump 3. Similarly, the heat of the LED thin film portion 1b of the semiconductor light emitting element 1 is transmitted from the p-type nitride semiconductor layer 11 in the LED thin film portion 1b through the p-type electrode 19 and the p-type electrode pad 5 through the second metal bump 4. Heat can be radiated to the mounting substrate 2 side. Thereby, it can be set as the light-emitting device 20 which is excellent in heat dissipation and can aim at the improvement of a light output more.

  In the semiconductor light emitting device 1 of the present embodiment, a laminated structure film of a nitride semiconductor layer that becomes the LED thin film portion 1b is sequentially formed on a wafer made of a nitride semiconductor material by a crystal growth method such as the MOVPE method. Thereafter, the nitride semiconductor layer of the nitride semiconductor layer to be the LED thin film portion 1b is nitrided so that the n-type electrode pad 6 and the like can be provided on the outer peripheral portion 1d on the one surface side of the nitride semiconductor substrate 1c. Etching is performed by RIE (Reactive Ion Etching) method until the surface to be the physical semiconductor substrate 1c is exposed. Subsequently, after the n-type electrode pad 6, the p-type electrode 19 and the p-type electrode pad 5 are formed by film formation by electron beam evaporation, photolithography technique and etching technique, respectively, a wafer made of a nitride semiconductor material is formed. The semiconductor light emitting element 1 can be formed by dicing.

  Note that the semiconductor light emitting device 1 of this embodiment is compared with the one in which the n-type electrode pad 6 or the like is bonded to the crystal growth surface of the stacked structure film exposed by etching the stacked structure film of the nitride semiconductor layer. When the n-type electrode pad 6 or the like is bonded to the outer peripheral portion 1d of the nitride semiconductor substrate 1c by etching the multi-layer structure film of the nitride semiconductor layer, the internal stress of the multi-layer structure film accompanying the etching is increased. Can be reduced. Therefore, even when the amount of heat conducted from the semiconductor light emitting element 1 to the mounting substrate 2 via the metal bumps 3 and 4 is large, the life of the semiconductor light emitting element 1 can be extended.

  Further, as another method for forming the semiconductor light emitting device 1 of the present embodiment, after the LED thin film portion 1b is formed on the sapphire wafer via the low temperature growth buffer layer, the wafer is made of a nitride semiconductor material formed separately. The LED thin film portion 1b is joined by thermocompression bonding or the like. Thereafter, the sapphire wafer is peeled to obtain a wafer in which a nitride semiconductor layer laminated structure film to be the LED thin film portion 1b is formed on the nitride semiconductor material wafer. The semiconductor light emitting device 1 can also be formed using a wafer on which the laminated structure film of the nitride semiconductor layer is formed. In this case, the LED thin film portion 1b in contact with one surface of the nitride semiconductor substrate 1c becomes the p-type nitride semiconductor layer 11 as in the first embodiment.

1 Semiconductor Light Emitting Element 1a Zinc oxide substrate (conductive substrate)
1b LED thin film part 1c Nitride semiconductor substrate (conductive substrate)
DESCRIPTION OF SYMBOLS 1d Outer peripheral part 2 Mounting substrate 3 1st metal bump 4 2nd metal bump 11 p-type nitride semiconductor layer 13 n-type nitride semiconductor layer 20 Light-emitting device

Claims (3)

A semiconductor light emitting device comprising a conductive substrate and an LED thin film portion formed on one surface side of the conductive substrate and having a p-type nitride semiconductor layer and an n-type nitride semiconductor layer, and the conductivity of the semiconductor light emitting device A mounting substrate on which the semiconductor light emitting element is mounted via a metal bump so that the other surface side of the substrate is a light extraction surface,
The semiconductor light emitting device includes the LED thin film portion smaller than the conductive substrate so that an outer peripheral portion on the one surface side of the conductive substrate is exposed in a plan view, and the metal bumps are formed of the conductive conductive material. A plurality of first metal bumps provided on the outer periphery of the substrate so as to surround the LED thin film portion, and a plurality of second metals provided on the surface side of the LED thin film portion facing the conductive substrate. A light emitting device characterized by being a bump.   The conductive substrate of the semiconductor light emitting device is a zinc oxide substrate, and the p-type nitride semiconductor layer in the LED thin film portion is provided on the one surface side of the conductive substrate with respect to the n-type nitride semiconductor layer. The light-emitting device according to claim 1. The conductive substrate of the semiconductor light-emitting element is a nitride semiconductor substrate, and the n-type nitride semiconductor layer in the LED thin film portion is closer to the one surface side of the conductive substrate than the p-type nitride semiconductor layer The light-emitting device according to claim 1, further comprising:

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