JP2008244302A - Compound semiconductor light-emitting element, lighting device using the same, and production method of the compound semiconductor light-emitting element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve reliability of a compound semiconductor light-emitting element wherein a nanocolumn is formed on a conductive substrate, insulation between nanololumns and between a p-type layer and an n-type layer is ensured therebetween and an insulator which protects a light-emitting layer is buried. <P>SOLUTION: In a compound semiconductor element, a fine particle 41 consisting of a material which is chargeable, such as, silicon and becomes insulating by thermal oxidation is used as a material of an insulator 4, a positive voltage is applied from a power supply 13 to a substrate 2 wherein a nanocolumn is planted and the fine particle 41 is provided with negative charge on colliding with electron and is subjected to electrostatic attraction to the substrate 2 (a) to (c). Thereafter, the fine particle 41 changes to insulating properties through heat treatment under an oxygen atmosphere, and is dissolved and solidified, and is immobilized as an oxide layer between nanocolumns 3 (d). Accordingly, it is possible to embed the insulator 4 readily and uniformly, without having to break down the nanocolumn 3 such as spin coat, thus improving the reliability of the element. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a compound semiconductor light emitting element such as a III-V group compound semiconductor, a lighting device using the same, and a method for manufacturing the compound semiconductor light emitting element. In particular, the semiconductor element includes a column called a nanocolumn or a nanorod on a substrate. The present invention relates to a structure in which a columnar crystal structure having a nanometer size is formed.

In recent years, compound semiconductor light emitting devices having a light emitting layer composed of a nitride semiconductor or an oxide semiconductor have attracted attention. As an example of the structure of this light emitting element, an n-cladding layer and a contact layer composed of an n ⁺ -GaN layer in which a sapphire substrate is used as a growth substrate and silicon (Si) is doped below the light emitting layer, an upper portion of the light emitting layer An electron block layer made of p-Al _x Ga _1-x N doped with magnesium (Mg) and a p-GaN contact layer on the electron block layer are formed. In these light-emitting elements using so-called bulk crystals, the lattice constants of the sapphire substrate and the nitride or oxide semiconductor layer are greatly different and are formed as a thin film on the substrate. Since threading dislocations are included, it is difficult to increase the efficiency of the light emitting element.

Therefore, Patent Document 1 is known as a conventional example of a technique for solving such a problem. In this conventional example, an n-type GaN buffer layer serving as an n-type electrode is formed on a sapphire substrate, and then a large number of the columnar crystal structures (nanocolumns) arranged in an array are formed. A light-emitting element is configured by embedding a transparent insulating layer such as SOG (Spin-on-Glass), SiO _2, or epoxy resin and forming a transparent electrode and an electrode pad to be a p-type electrode. In particular, the GaN nanocolumn includes an n-type GaN nanocolumn, an InGaN quantum well serving as a light emitting layer, and a p-type GaN nanocolumn. If this nanocolumn is used, it is possible to reduce the threading dislocations of the bulk crystal to be almost eliminated, and non-radiative recombination due to the threading dislocations can be reduced, so that the light emission efficiency can be improved.

On the other hand, Patent Document 2 is a light-emitting element using a nanocolumn, but it emits light with an unusual structure in which a doping substance is adsorbed on the outer periphery of the nanocolumn and electrons and holes are sucked out to have respective polarities of p and n. Devices have been proposed. Specifically, first, a metal layer to be an electrode is formed on a substrate, and then a nanocolumn such as ZnO is formed. Subsequently, the lower doping substance is adsorbed by doping, and an insulating polymer is filled between the columns by spin coating, then the upper half is peeled off by wet etching, and a thin photoresist is spin-coated to remove the nanocolumns in that portion. Authentic (light emitting) layer. Further, the upper doping substance is adsorbed by doping, and after filling the insulating polymer by spin coating, another electrode is formed.
JP 2005-228936 A JP 2005-303300 A

  In the prior art as described above, in order to protect adjacent nanocolumns or to ensure insulation between adjacent nanocolumns, when the transparent insulator is embedded between the columns, application of SOG or the like is performed on the wafer. In general, spin coating is performed by rotating the wafer, the force applied during spin coating cannot be withstood, the nanocolumns may fall down and break down, or the gap between the nanocolumns, especially deep inside the substrate side. There is a problem that it is difficult to fill with transparent insulator. If the transparent insulator is not reliably and uniformly filled, other impurity elements are mixed in the gap to cause a short circuit, the light emitting layer is not protected, and causes leakage current on the nanocolumn surface, etc. There is a problem in reliability.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a compound semiconductor light-emitting element capable of improving the reliability of the element by reliably and uniformly filling an insulator into a very fine gap formed by a columnar crystal structure, an illumination device using the same, and a semiconductor light-emitting element It is to provide a manufacturing method.

  The compound semiconductor light-emitting device of the present invention is a compound semiconductor light-emitting device having a nanoscale columnar crystal structure on a conductive substrate, and an insulator is embedded between the columnar crystal structures. Is characterized in that it consists of an oxide layer that becomes insulating by thermal oxidation of the fine particles embedded by electrostatic adsorption.

  The method for producing a compound semiconductor light emitting device of the present invention includes a compound semiconductor light emitting device having a nanoscale columnar crystal structure on a conductive substrate, and an insulator embedded between the columnar crystal structures. In this manufacturing method, a voltage of one polarity is applied to the substrate on which the columnar crystal structure is grown, and the other polarity is charged to fine particles made of a material that can be charged and becomes insulating by thermal oxidation. And a step of attaching the fine particles as an insulating oxide layer between the columnar crystal structures by performing a heat treatment in an oxygen atmosphere.

  According to the above configuration, a nanoscale columnar crystal structure called a nanocolumn or a nanorod is formed on a substrate having conductivity and preferably translucency with respect to the emission wavelength, for example, SiC or ZnO, In addition, an insulator is embedded between the columnar crystal structures to ensure insulation between the columnar crystal structures and between the p-type layer and the n-type layer of the columnar crystal structure, and to protect the light emitting layer. In the compound semiconductor light emitting device and the manufacturing method thereof, the insulator is made of fine particles made of a material that can be charged and becomes insulating by thermal oxidation, such as aluminum, titanium, nickel, particularly preferably silicon powder, Applying a voltage of one polarity to the substrate on which the columnar crystal structure is grown, charging the other polarity to the fine particles, and electrostatically adsorbing the fine particles to the substrate, Deep depths of the substrate side between Jo crystal structure so as put embedding an insulator. Then, the embedded insulator is subjected to heat treatment in an oxygen atmosphere to change into insulation as described above, and is melted and solidified to be fixed as an oxide layer between the columnar crystal structures.

  Therefore, when the insulator is embedded in the very fine gap formed by the columnar crystal structure, the insulator is easily and uniformly embedded deeply into the depth without damaging the columnar crystal structure like spin coating. And the reliability of the element can be improved.

  Furthermore, in the compound semiconductor light emitting device of the present invention, the oxide layer is formed on the first insulator layer formed on the substrate side with respect to the light emitting layer in the columnar crystal structure, and on the first insulator layer. And a reflective layer formed on the substrate side of the light emitting layer, and a second insulator layer formed on the reflective layer and having translucency with respect to the light emission wavelength of the light emitting layer. It is characterized by being.

  In the method for producing a compound semiconductor light emitting device of the present invention, the step of adhering the fine particles to the substrate and the heat treatment step are repeated at least three times. In the first repetition step, the light emitting layer in the columnar crystal structure is obtained. The first insulator layer is formed on the substrate side, and in the second repeating step, the reflective layer is formed on the first insulator layer and on the substrate side with respect to the light emitting layer, and the third time In the repeating step, a second insulator layer having translucency with respect to the emission wavelength of the light emitting layer is formed on the reflective layer.

  According to the above configuration, the oxide layer has a three-layer structure of the first insulator layer, the reflective layer, and the second insulator layer in order from the substrate side, and includes a p-type layer, a light emitting layer, and n The first insulator layer and the reflective layer are formed on the substrate side of the light emitting layer in the columnar crystal structure that is laminated in the order of the mold layer or vice versa, and the second insulator layer Has a light-transmitting property with respect to the emission wavelength of the light-emitting layer, so that the reflective layer does not short-circuit the p-type layer and the n-type layer, and is generated in the light-emitting layer and has a columnar crystal structure. The light radiated from the outer peripheral surface of the body can be efficiently extracted by reflecting the light on the side opposite to the substrate by the reflective layer.

  Furthermore, the compound semiconductor light emitting device of the present invention is further characterized by further comprising a phosphor layer in the second insulator layer.

  According to said structure, the light emission wavelength by the said light emitting layer, such as whitening, can be easily converted into arbitrary wavelengths by the said fluorescent substance layer.

  In the compound semiconductor light emitting device of the present invention, the substrate is made of a light-transmitting material, and a reflective film is formed on the side of the substrate opposite to the side on which the columnar crystal structure is formed. It is characterized by being.

  According to said structure, the light radiated | emitted from the said light emitting layer to the substrate side in the columnar crystal structure is reflected toward the columnar crystal structure side surface which is a light extraction direction with the reflecting film provided in the back surface of the substrate. Therefore, the light extraction efficiency can be improved.

  Furthermore, the lighting device of the present invention is characterized by using the compound semiconductor light emitting element.

  According to said structure, the illuminating device which can improve the reliability of a light emitting element is realizable.

  In the method for producing a compound semiconductor light emitting device of the present invention, the substrate is vibrated in the step of attaching the fine particles to the substrate.

  According to said structure, by making it vibrate, the said microparticles | fine-particles can be uniformly embedded to the said deep bottom between columnar crystal structures.

  Furthermore, in the method for producing a compound semiconductor light emitting device of the present invention, in the step of attaching the fine particles to the substrate, the voltage of the other polarity applied to the fine particles is equal to or less than the band gap energy of the columnar crystal structure. It is characterized by that.

  According to said structure, it can prevent that microparticles | fine-particles adhere to the front end side of the said columnar crystal structure, and it can embed uniformly to the said deep bottom.

  As described above, the compound semiconductor light emitting device of the present invention and the manufacturing method thereof are formed on a substrate having conductivity and preferably translucency with respect to the emission wavelength, and nanoscale columnar crystals called nanocolumns and nanorods. Structures are formed, and insulation between the columnar crystal structures is ensured between the columnar crystal structures and between the p-type layer and the n-type layer of the columnar crystal structure, and to protect the light emitting layer. In the compound semiconductor light-emitting device in which an object is embedded and a method for manufacturing the compound semiconductor light-emitting element, the columnar crystal structure is grown by using fine particles made of a material that can be charged and becomes insulating by thermal oxidation as the insulator. A voltage of one polarity is applied to the substrate, the other particle is charged with the other polarity, and the fine particles are electrostatically adsorbed on the substrate, and then heat treatment is performed in an oxygen atmosphere, thereby insulating the fine particles. Varied, and immobilized as oxide layer between the melted and solidified columnar crystal structure.

  Therefore, when the insulator is embedded in the ultrafine gap formed by the columnar crystal structure, the insulator is embedded deeply and deeply easily and uniformly without destroying the columnar crystal structure as in spin coating. Therefore, the reliability of the element can be improved.

  Furthermore, in the compound semiconductor light-emitting device and the method for manufacturing the same according to the present invention, as described above, the oxide layer is arranged in order from the substrate side, the first insulator layer, the reflective layer, and the second insulator layer. The first insulator layer and the light emitting layer in the columnar crystal structure formed by stacking the p-type layer, the light emitting layer, and the n type layer in this order, or vice versa. In addition to forming a reflective layer, the second insulator layer is translucent to the emission wavelength of the light emitting layer.

  Therefore, the light that is generated in the light emitting layer and emitted from the outer peripheral surface of the columnar crystal structure is not reflected in the reflective layer without short-circuiting the p-type layer and the n-type layer by the reflective layer. It can be efficiently taken out by being reflected on the opposite side of the substrate.

  Furthermore, the compound semiconductor light emitting device of the present invention further includes a phosphor layer in the second insulator layer as described above.

  Therefore, the emission wavelength of the light emitting layer, such as whitening, can be easily converted to an arbitrary wavelength.

  In the compound semiconductor light emitting device of the present invention, as described above, the substrate is translucent and a reflective film is formed on the side of the substrate opposite to the side on which the columnar crystal structure is formed.

  Therefore, the light radiated from the light emitting layer to the substrate side in the columnar crystal structure is reflected toward the surface of the columnar crystal structure side which is the light extraction direction by the reflective film, so that the light extraction efficiency can be improved. it can.

  Furthermore, the lighting device of the present invention uses the compound semiconductor light emitting element as described above.

  Therefore, an illuminating device that can improve the reliability of the light-emitting element can be realized.

  Moreover, the manufacturing method of the compound semiconductor light-emitting device of the present invention vibrates the substrate in the step of attaching the fine particles to the substrate as described above.

  Therefore, the fine particles can be uniformly embedded to the deep depth between the columnar crystal structures.

  Furthermore, in the method for producing a compound semiconductor light emitting device of the present invention, as described above, in the step of attaching the fine particles to the substrate, the voltage of the other polarity applied to the fine particles is set to a band of the columnar crystal structure. Below the gap energy.

  Therefore, the fine particles can be prevented from adhering to the tip side of the columnar crystal structure, and can be uniformly embedded deeply into the depth.

[Embodiment 1]
FIG. 1 is a cross-sectional view schematically showing the structure of a light-emitting diode 1 which is a compound semiconductor light-emitting element according to the first embodiment of the present invention. The light-emitting diode 1 has a structure in which a plurality of nanocolumns 3 are planted on a substrate 2 made of SiC or ZnO having translucency and conductivity, and an insulator 4 is embedded between them. 3, a bonding electrode 6 is laminated from a transparent electrode 5, and a reflective electrode 7 is laminated on the surface of the substrate 2 on the side opposite to the nanocolumn 3.

  The nanocolumn 3 includes an n-type nitride semiconductor layer 3a, a light emitting layer 3b, and a p-type nitride semiconductor layer 3c, which are sequentially stacked from the substrate 2 side. When the light emitting layer 3b is formed of n-type InGaN, AlInGaN, or AlGaN, the composition ratio of In and Al is appropriately adjusted, or n-type impurities such as Si, Ge, and S, and p-type impurities such as Zn and Mg. The light emission color can be adjusted to a desired color in the range of ultraviolet to blue by appropriately doping. As a method for creating such a nanocolumn 3, for example, the above-mentioned Patent Document 1 and Japanese Patent Application Laid-Open No. 2007-49062 filed by the present applicant can be used as examples. For the growth of the nanocolumn 3, molecular metal epitaxy (MBE), hydride vapor phase epitaxy (HVPE), etc. can be used, including metal organic chemical vapor deposition (MOCVD).

  It should be noted that in the light-emitting diode 1, the insulator 4 is made of an oxide layer that becomes insulating by thermally oxidizing fine particles embedded by electrostatic adsorption. Specifically, FIG. 2 is a cross-sectional view schematically showing a method for producing the insulator 4 in the light emitting diode 1, and FIG. 3 schematically shows the structure of the device 11 used for embedding the insulator 4. FIG. The substrate 2 on which the nanocolumn 3 has been grown is placed on the stage 12 of the apparatus 11, and a predetermined positive voltage is applied from the power supply 13. On the other hand, the fine particles 41 to be the insulator 4 are materials that can be charged, become insulating by thermal oxidation, and are transparent to the emission wavelength of the light emitting layer 3b, such as aluminum, titanium, nickel, Preferably, silicon is made of fine powder having a particle size of several nanometers to several micrometers, and is preliminarily stored in a storage container 14 disposed on the stage 12, and is sprayed therefrom. At this time, the fine particles 41 are charged so as to have a predetermined negative charge by collision with the electrons 16 generated by the electron generator 15.

  As a result, as shown in FIG. 2A, the fine particles 41 dispersed on the substrate 2 are electrostatically attracted to the substrate 2. Here, if the voltage applied from the power source 13 is the band gap energy of the nanocolumn 3, for example, 3.4 eV or less for GaN, the region to be mainly charged is the n-type nitride semiconductor layer 3a. Oxidizing metal fine particles 41 charged to the opposite polarity do not prevent fine particles that arrive after the nanocolumns 3 from adhering to the tip side of the nanocolumns 3 and enter the bottom side between the nanocolumns 3. As shown by 2 (b), the n-type nitride semiconductor layer 3a is deposited on the surface of the substrate 2 from the side surface, that is, from the bottom side on the substrate 2 side between the nanocolumns 3. Further, at this time, by allowing the stage 12 to vibrate, the fine particles 41 can be deposited more uniformly to the deep depth.

  Thus, as shown in FIG. 2C, when the fine particles 41 are deposited up to the height of the nanocolumn 3 so as to cover at least the light emitting layer 3b and cover the p-type nitride semiconductor layer 3c, the fine particles 41 are deposited. 2 is finished, and then heat treatment is performed in an oxygen atmosphere, whereby the fine particles 41 change to insulating properties and melt and solidify, and as shown in FIG. To be fixed as an oxide layer.

  Thereafter, the transparent electrode 5 and the bonding electrode 6 are laminated on the p-type nitride semiconductor layer 3c of the nanocolumn 3 exposed from the insulator 4, and a reflective electrode is formed on the surface of the substrate 2 opposite to the nanocolumn 3 By laminating 7, the light emitting diode 1 as shown in FIG. 1 is completed. When a positive voltage is applied to the bonding electrode 6 and a negative voltage is applied to the reflective electrode 7, electrons and holes are combined in the light emitting layer 3b to generate blue or ultraviolet light. Directly from the light emitting layer 3b as indicated by F1, or as indicated by an arrow F2, the light passes through the transparent substrate 2 and is appropriately reflected by the reflective electrode 7, and then passes through the transparent substrate 2 again. The light is emitted from the transparent electrode 5 on the light extraction side to the outside.

  With this configuration, an insulator 4 is provided between the nanocolumns 3 to secure insulation between the nanocolumns 3 and between the n-type nitride semiconductor layer 3a and the p-type nitride semiconductor layer 3c, and to protect the light emitting layer 3b. In order to improve the reliability of the device, the insulator 4 can be embedded deeply between the nanocolumns 3 easily and uniformly without damaging the nanocolumns 3 such as spin coating. Can do. In addition, the insulator 4 can be uniformly embedded between the nanocolumns 3, the transparent electrode 5 can be easily formed, and the yield can be improved. Furthermore, the light-emitting diode 1 that can improve the reliability of the light-emitting element as described above is extremely suitable for a lighting device.

[Embodiment 2]
FIG. 4 is a cross-sectional view schematically showing the structure of a light-emitting diode 21 which is a compound semiconductor light-emitting element according to the second embodiment of the present invention. The light-emitting diode 21 is similar to the light-emitting diode 1 described above, and corresponding portions are denoted by the same reference numerals and description thereof is omitted. It should be noted that in the light emitting diode 21, the insulator 4 ′ is formed on the first insulator layer 4a formed on the substrate 2 side with respect to the light emitting layer 3b, and on the first insulator layer 4a. In addition, the reflective layer 4b formed on the substrate 2 side of the light emitting layer 3b, and the second insulator layer 4c formed on the reflective layer 4b and having translucency with respect to the emission wavelength of the light emitting layer 3b. It is comprised with.

  FIG. 5 is a cross-sectional view schematically showing a part of a method for producing the insulator 4 ′ in the light emitting diode 1. First, as shown in FIG. 2A to FIG. 2B, it is the same that the fine particles 41 are deposited on the surface of the substrate 2 from the side surface of the n-type nitride semiconductor layer 3a. In this step, after the fine particles 41 are deposited to a predetermined height lower than that of the light emitting layer 3b, the heat treatment is performed once, and as shown in FIG. 5A, the first insulator layer 4a. Are stacked.

  Subsequently, as shown in FIG. 5B, the voltage applied to the substrate 2 from the power source 13 is equal to or higher than the band gap energy, while the reflective metal fine particles are charged to the same positive polarity as the substrate 2. When 42 is attached to a predetermined height lower than that of the light emitting layer 3b, it does not adhere to the side surfaces of the light emitting layer 3b and the p-type nitride semiconductor layer 3c, and the transparent first insulator layer 4a that has already been formed. Only deposited on top. Thereafter, by performing heat treatment again, as shown in FIG. 5C, the first insulator is not short-circuited between the n-type nitride semiconductor layer 3a and the p-type nitride semiconductor layer 3c. The reflective layer 4b is formed only on the layer 4a.

  Further, as in FIG. 2A, the oxide metal fine particles 41 charged in the opposite polarity to the substrate 2 are stacked, and heat treatment is performed in an oxygen atmosphere. As described above, the insulator 4 ′ composed of the three layers of the first insulator layer 4a, the reflective layer 4b, and the second insulator layer 4c can be embedded uniformly between the nanocolumns 3.

  Thus, by repeating the process of attaching the fine particles 41 and 42 to the substrate 2 and the process of heat treatment three times, and forming the insulator 4 ′ from the three layers, as shown by the arrow F3 in FIG. The light emitted from the outer peripheral surface of the nanocolumn 3 generated in the light emitting layer 3b is reflected to the opposite side of the substrate 2 by the reflective layer 4b, and the proportion absorbed by the adjacent nanocolumn 3 is reduced efficiently. Can be taken out.

[Embodiment 3]
FIG. 6 is a cross-sectional view schematically showing the structure of a light-emitting diode 31 which is a compound semiconductor light-emitting element according to the third embodiment of the present invention. The light-emitting diode 31 is similar to the light-emitting diode 21 described above, and corresponding portions are denoted by the same reference numerals and description thereof is omitted. It should be noted that in this light emitting diode 31, the insulator 4 ″ further includes a phosphor layer 4d in the second insulator layer 4c in addition to the insulator 4 ′.

  By comprising in this way, the light emission wavelength by the said light emitting layer 3b, such as whitening, can be easily converted into arbitrary wavelengths by the said fluorescent substance layer 4d.

It is sectional drawing which shows typically the structure of the light emitting diode which is a compound semiconductor light emitting element concerning the 1st Embodiment of this invention. It is sectional drawing which shows typically the production method of the insulator in the light emitting diode shown in FIG. It is a figure which shows typically the structure of the apparatus used for embedding the insulator shown in FIG. It is sectional drawing which shows typically the structure of the light emitting diode which is a compound semiconductor light emitting element concerning the 2nd Embodiment of this invention. FIG. 5 is a cross-sectional view schematically showing a part of a method for producing an insulator in the light emitting diode shown in FIG. 4. It is sectional drawing which shows typically the structure of the light emitting diode which is a compound semiconductor light emitting element concerning the 3rd Embodiment of this invention.

Explanation of symbols

1, 21 and 31 Light-emitting diode 2 Substrate 3 Nanocolumn 3a n-type nitride semiconductor layer 3b light-emitting layer 3c p-type nitride semiconductor layer 4, 4 ′, 4 ″ insulator 4a first insulator layer 4b reflective layer 4c second Insulator layer 4d Phosphor layer 5 Transparent electrode 6 Bonding electrode 7 Reflective electrode 11 Device 12 Stage 13 Power supply 14 Containment vessel 15 Electron generator 16 Electron 41, 42 Fine particles

Claims (9)

In a compound semiconductor light emitting device having a nanoscale columnar crystal structure on a conductive substrate, and an insulator embedded between the columnar crystal structures,
The compound semiconductor light emitting device, wherein the insulator is formed of an oxide layer that becomes insulating by thermally oxidizing fine particles embedded by electrostatic adsorption. The oxide layer is
A first insulator layer formed on the substrate side of the light emitting layer in the columnar crystal structure;
A reflective layer formed on the first insulator layer and closer to the substrate than the light emitting layer;
The compound semiconductor light-emitting element according to claim 1, further comprising: a second insulator layer formed on the reflective layer and having translucency with respect to an emission wavelength of the light-emitting layer.   The compound semiconductor light-emitting element according to claim 2, further comprising a phosphor layer in the second insulator layer.   The said board | substrate consists of the material which has translucency, and the reflecting film is formed in the opposite side to the side in which the said columnar crystal structure is formed in this board | substrate. The compound semiconductor light-emitting device according to any one of the above.   An illumination device using the compound semiconductor light-emitting element according to claim 1. In a method for manufacturing a compound semiconductor light emitting device having a nanoscale columnar crystal structure on a conductive substrate, and an insulator embedded between the columnar crystal structures,
A voltage of one polarity is applied to the substrate on which the columnar crystal structure has been grown, and the other polarity is charged to a fine particle made of a material that can be charged and becomes insulative by thermal oxidation to adhere to the substrate. Process,
And a step of embedding the fine particles as an insulating oxide layer between the columnar crystal structures by performing a heat treatment in an oxygen atmosphere. Repeating the step of attaching the fine particles to the substrate and the step of the heat treatment at least three times;
In the first repeating step, a first insulator layer is formed on the substrate side of the light emitting layer in the columnar crystal structure,
In the second repeating step, a reflective layer is formed on the first insulator layer and on the substrate side of the light emitting layer,
7. The compound semiconductor light emitting element according to claim 6, wherein in the third repeating step, a second insulator layer having translucency with respect to the emission wavelength of the light emitting layer is formed on the reflective layer. Manufacturing method.   8. The method of manufacturing a compound semiconductor light-emitting element according to claim 6, wherein in the step of attaching the fine particles to the substrate, the substrate is vibrated.   9. The method according to claim 6, wherein in the step of attaching the fine particles to the substrate, the voltage of the other polarity applied to the fine particles is equal to or lower than the band gap energy of the columnar crystal structure. The manufacturing method of the compound semiconductor light-emitting device of description.

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