JP2009054864A - Nitride gallium-based semiconductor surface light emitting element and method of fabricating same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of fabricating a nitride gallium-based semiconductor surface light emitting element having excellent electric characteristics. <P>SOLUTION: A substrate product W2 including a semiconductor structure 45 of a principal surface 45a formed of a Ga surface is prepared, and a substrate product W1 including a semiconductor structure 19 of a principal surface 19a formed of a N surface is prepared. The semiconductor structure 19 is fabricated by growing a gallium nitride-based semiconductor on a nitrified surface of a sapphire substrate by an MBE method. The principal surface (Ga surface) 45a of the substrate product W2 and the principal surface 19a (N surface) of the substrate product W2 are opposed to each other. The principal surface (Ga surface) 45a and principal surface (N surface) 19a are brought into contact with each other and heat-treated to fusion bond the semiconductor structure 19 and semiconductor structure 45 together. Consequently, the semiconductor products 19 and 45 are united to form a junction J. At the junction J, a junction surface (N surface) of the semiconductor structure 19 and a junction surface (Ga surface) of the semiconductor structure 45 are joined together. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a gallium nitride based semiconductor surface light emitting device and a method for manufacturing a gallium nitride based semiconductor surface light emitting device.

Patent Document 1 describes a light-emitting element made of a nitride semiconductor. This light emitting element can improve single mode stability. In the interface region formed by joining the first nitride semiconductor layer and the second nitride semiconductor layer, a plurality of voids made of cylindrical cavities are periodically provided so as to form a diffraction grating. . A diffraction grating having this structure provides a DFB laser element having high single mode stability.
JP 2000-340882 A

  In developing a photonic crystal surface emitting laser, a technique for creating a photonic layer having a two-dimensional periodic structure is important. In Patent Document 1, a first wafer is manufactured by a crystal growth method, and after a second wafer is similarly manufactured by a crystal growth method, periodic grooves are formed in the first wafer. Thereafter, the first wafer and the second wafer are bonded by pressure heating.

  Conventional gallium nitride-based semiconductors for semiconductor devices have utilized semiconductors that have been crystal-grown on the underlying Ga surface. For this reason, the outermost surface of the grown crystal is also a Ga surface, and the first wafer and the second wafer having the same Ga surface are bonded together by pressure heating. However, according to the inventor's experiment, unlike a crystal having no polarity with respect to the epitaxial growth direction such as GaAs, a desired junction is not formed between hexagonal crystals such as gallium nitride, which causes a problem in electrical characteristics. Etc. That is, even if a physical bond is formed, there is a problem caused by the fact that the polarities of the crystal planes appearing on the bonded surface are the same.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a gallium nitride based semiconductor surface light emitting device having good electrical characteristics, and this gallium nitride based semiconductor surface light emitting device. It is an object of the present invention to provide a method for manufacturing the above.

  A gallium nitride based semiconductor surface light emitting device according to an aspect of the present invention includes: (a) a first semiconductor structure including one or a plurality of gallium nitride based semiconductor layers and having a bonding surface; and (b) one or a plurality of nitridings. A second semiconductor structure made of a gallium-based semiconductor layer and having a bonding surface, wherein one of the bonding surfaces of the first and second semiconductor structures is made of a Ga surface, and the first and second semiconductors The other of the bonding surfaces of the structure is an N-plane, and the bonding surface of the second semiconductor structure is provided with a periodic structure for a photonic crystal. The bonding surface and the bonding surface of the second semiconductor structure are fused to each other, and the second semiconductor structure includes an active layer.

  According to the present invention, when the first and second semiconductor structures are fused, the bonding surfaces having different polarities are fused, so that the photonic crystal structure provided by the fusion is provided. There is provided a surface light emitting device that is not related to a problem related to polarity inherent in a hexagonal gallium nitride semiconductor.

  In the gallium nitride based semiconductor surface light emitting device of the present invention, the periodic structure for the photonic crystal may be composed of a plurality of voids periodically arranged on the bonding surface of the second semiconductor structure.

  According to the gallium nitride based semiconductor surface light emitting device, a plurality of openings periodically arranged on the joint surface of the second semiconductor structure are formed by the fusion of the joint surface capable of providing suitable electrical characteristics. A photonic crystal structure is provided that is enclosed by a semiconductor structure.

  In the gallium nitride based semiconductor surface light emitting device of the present invention, the periodic structure for the photonic crystal is composed of a plurality of insulating members periodically arranged in the gallium nitride based semiconductor of the second semiconductor structure. Can do.

  This gallium nitride based semiconductor surface light emitting device. The fusion of the bonding surfaces that can provide suitable electrical characteristics provides a photonic crystal structure comprising a plurality of insulating members periodically arranged in a gallium nitride based semiconductor.

  In the gallium nitride based semiconductor surface light emitting device of the present invention, the main surface of the first semiconductor structure is formed of any one of GaN, AlGaN, InGaN, and a mixed crystal thereof, and the second semiconductor The main surface of the structure may be formed of any one of GaN, AlGaN, InGaN, and mixed crystals thereof.

  Another aspect of the present invention is a method of fabricating a gallium nitride based semiconductor surface light emitting device including a photonic crystal. This method comprises (a) a step of epitaxially growing a first semiconductor structure comprising one or more gallium nitride based semiconductor layers on a first substrate, and (b) comprising one or more gallium nitride based semiconductor layers. Epitaxially growing a second semiconductor structure on a second substrate; (c) forming a periodic structure for a photonic crystal in one of the first and second semiconductor structures; (D) after forming the periodic structure, and fusing the main surface of the first semiconductor structure and the main surface of the second semiconductor structure facing each other; (e) after the fusing Removing either one of the first and second substrates, wherein the main surface of the first semiconductor structure has a Ga surface or an N surface, and the second semiconductor structure The main surface of the object has a Ga surface or an N surface. , The second semiconductor structure including an active layer.

  According to this method, since the main surface of the N surface of the first semiconductor structure and the main surface of the Ga surface of the second semiconductor structure face each other and are fused, these joint surfaces have opposite polarities. It has a crystal face. Therefore, there is no problem in electrical characteristics due to the bonding of crystal faces with the same polarity.

  In the method according to the present invention, it is preferable that the gallium nitride based semiconductor layer of the first semiconductor structure is formed using a molecular beam epitaxy method. By molecular beam epitaxy, it becomes easy to grow a gallium nitride based semiconductor having an N plane. In the method according to the present invention, it is preferable that the gallium nitride based semiconductor layer of the second semiconductor structure is formed using a metal organic chemical vapor deposition method. The metal organic chemical vapor deposition method is suitable for forming a multilayer film including a gallium nitride based semiconductor layer.

  In the method according to the present invention, the periodic structure for the photonic crystal may include a plurality of openings periodically arranged on the main surface of the second semiconductor structure. The plurality of openings are formed by patterning the gallium nitride based semiconductor layer by lithography and etching, for example. Alternatively, in the method according to the present invention, the periodic structure for the photonic crystal may be composed of a plurality of insulating members periodically arranged in a gallium nitride based semiconductor of the second semiconductor structure. The plurality of insulating members are formed by forming a plurality of insulating members periodically arranged from the insulating film by depositing an insulator, photolithography and etching, and embedding these insulating members with a gallium nitride based semiconductor.

  In the method according to the present invention, the main surface of the first semiconductor structure is formed of any one of GaN, AlGaN, InGaN, and a mixed crystal thereof. In the method according to the present invention, the main surface of the second semiconductor structure is formed of any one of GaN, AlGaN, InGaN, and a mixed crystal thereof.

  In the method according to the present invention, the first substrate is preferably a sapphire substrate. The main surface of the first semiconductor deposit has an N-plane, and the method nitrides the surface of the sapphire substrate before growing the first semiconductor structure on the first substrate. A process can be further provided. A gallium nitride based semiconductor having an N surface is formed on a sapphire substrate having a nitrided surface.

  The above and other objects, features, and advantages of the present invention will become more readily apparent from the following detailed description of preferred embodiments of the present invention, which proceeds with reference to the accompanying drawings.

  As described above, according to the present invention, a gallium nitride based semiconductor surface light emitting device having good electrical characteristics is provided, and a method for producing the gallium nitride based semiconductor surface light emitting device is provided.

  The knowledge of the present invention can be easily understood by considering the following detailed description with reference to the accompanying drawings shown as examples. Next, embodiments of the gallium nitride based semiconductor surface light emitting device and the method for producing the gallium nitride based semiconductor surface light emitting device of the present invention will be described with reference to the accompanying drawings. Where possible, the same parts are denoted by the same reference numerals.

  FIG. 1 is a schematic view showing main steps in a method for producing a first semiconductor structure for a gallium nitride based semiconductor surface light emitting device according to an embodiment of the present invention. In the following description, first, the fabrication of the first semiconductor structure on the substrate will be described, and then the fabrication of the second semiconductor structure on another substrate will be described. After the first and second semiconductor structures are fused to form an integral structure, one substrate is removed from the structure.

  A method for manufacturing the first semiconductor structure will be described with reference to FIGS. After the substrate 13 is placed in the molecular beam epitaxy (MBE) apparatus 11, the substrate 13 is heat-treated as shown in FIG. By this heat treatment, for example, thermal cleaning of the substrate surface is performed.

  The substrate 13 is preferably a sapphire substrate, for example. The surface of this sapphire substrate is nitrided. A gallium nitride based semiconductor having an N surface is formed on a sapphire substrate having a nitrided surface. In the following description, a sapphire substrate is used as the substrate 13.

As shown in FIG. 1B, the gallium nitride based semiconductor layer 15 is epitaxially grown on the main surface 13a of the substrate 13 by the MBE apparatus 11 while supplying a dopant of a predetermined conductivity type. The gallium nitride based semiconductor layer 15 can be made of, for example, p ⁺ -type GaN, and is used as a contact layer of a surface light emitting device. For the growth of p ⁺ -type GaN, a high Mg flux is supplied from an Mg K cell, a Ga flux from a Ga K cell, and an N flux from an N radical gun. The main surface 15a of the gallium nitride based semiconductor layer 15 has an N plane.

  Next, as shown in FIG. 1C, the gallium nitride based semiconductor layer 17 is epitaxially grown on the main surface 15a of the gallium nitride based semiconductor layer 15 by the MBE apparatus 11 while supplying a dopant having the same conductivity type as the above dopant. To do. The gallium nitride based semiconductor layer 17 can be made of, for example, p-type GaN, and is used as a p-type cladding layer of a surface light emitting device. For the growth of p-type GaN, Mg flux is supplied from the Mg K cell, Ga flux from the Ga K cell, and N flux from the N radical gun. The main surface 17a of the gallium nitride based semiconductor layer 17 has an N plane.

  Through these steps, the first semiconductor structure 19 was formed on the substrate 13. The first semiconductor structure 19 includes the gallium nitride based semiconductor layers 14, 15, and 17 in the above embodiment. The main surface 19a (main surface 17a) of the first semiconductor structure 19 has an N surface and is used as a bonding surface as will be described later. This bonding surface is not limited to the above specific example, but can be made of GaN, AlGaN, InGaN, or a mixed crystal thereof. In this embodiment, the second semiconductor deposit includes a p-type contact layer and a p-type cladding layer, but n-type can be used instead of p-type.

  FIG. 2 is a schematic view showing main steps in a method for producing a second semiconductor structure for a gallium nitride based semiconductor surface light emitting device according to an embodiment of the present invention. After the substrate 23 is placed in the metal organic vapor phase epitaxy (OMVPE) apparatus 21, the substrate 23 is heat-treated as shown in FIG. By this heat treatment, for example, thermal cleaning of the substrate surface is performed. As the substrate 23, for example, a GaN substrate, a sapphire substrate, or the like can be used. For example, since a c-plane GaN substrate having a Ga surface with a low dislocation density is available, it is preferable to use a GaN substrate as the substrate 13. A semiconductor stack such as an active layer having good crystal quality can be formed on the GaN substrate. In the following description, a GaN substrate is used as the substrate 13.

As shown in FIG. 2A, the gallium nitride based semiconductor layer 25 is epitaxially grown on the main surface 23a of the substrate 23 by the OMVPE apparatus 21 while supplying a dopant having a conductivity type opposite to that of the first semiconductor deposit. To do. The gallium nitride based semiconductor layer 25 can be made of, for example, n-type AlGaN, and is used as a cladding layer of a surface light emitting device. For the growth of n-type AlGaN, for example, raw materials of trimethylgallium (TMG), trimethylaluminum (TMA), and ammonia (NH ₃ ) are supplied. The main surface 25a of the gallium nitride based semiconductor layer 25 has a Ga surface. If necessary, a buffer layer can be deposited prior to formation of the cladding layer and can include multiple AlGaN layers as well as a single AlGaN semiconductor layer of the cladding layer.

Next, as illustrated in FIG. 2C, the gallium nitride based semiconductor layers 27, 29, and 31 are epitaxially grown on the main surface 25 a of the gallium nitride based semiconductor layer 25 by the OMVPE apparatus 21 without supplying a dopant. The gallium nitride based semiconductor layer 27 can be made of, for example, undoped GaN, and is used as a light guide layer of a surface light emitting device. The gallium nitride based semiconductor layer 29 can be composed of, for example, an undoped gallium nitride based semiconductor stack, and is used as an active layer of a quantum well structure of a surface light emitting device. The active layer includes well layers and barrier layers arranged alternately, and the well layer is made of, for example, InGaN, and the barrier layer is made of, for example, InGaN or GaN. The gallium nitride based semiconductor layer 31 can be made of, for example, undoped GaN, and is used as a light guide layer of a surface light emitting device. In the epitaxial growth of the gallium nitride based semiconductor layers 27, 29 and 31, the c-axis direction, that is, the Ga plane is maintained. For example, the main surface 31a of the gallium nitride based semiconductor layer 31 has a Ga surface. For the growth of InGaN, for example, trimethylgallium (TMG), trimethylindium (TMI), and ammonia (NH ₃ ) are supplied.

  Next, the gallium nitride based semiconductor layer 33 is epitaxially grown on the main surface 31 a of the gallium nitride based semiconductor layer 31 by the OMVPE apparatus 21 while supplying a dopant having the same conductivity type as that of the first semiconductor structure. The gallium nitride based semiconductor layer 33 can be made of, for example, p-type AlGaN, and is used as an electron block layer of a surface light emitting device. The main surface 33a of the gallium nitride based semiconductor layer 33 has a Ga surface.

  Through these steps, the semiconductor stack 35 was formed on the substrate 23. The semiconductor stack 35 includes the gallium nitride based semiconductor layers 25, 27, 29, 31, and 33 in the above embodiment. The main surface 35a (main surface 33a) of the semiconductor stack 35 has a Ga surface. In this embodiment, the gallium nitride based semiconductor layer 25 is n-type and the gallium nitride based semiconductor layer 33 is p-type, but the gallium nitride based semiconductor layer 25 is p-type and the gallium nitride based semiconductor layer 33 is n-type. There may be.

FIG. 3 is a schematic view showing main steps for producing a photonic crystal structure. As shown in FIG. 3A, an insulating film 37 is formed on the semiconductor stack 35. The insulating film 37 can be made of, for example, silicon oxide such as SiO ₂ . The silicon oxide is formed using a film forming apparatus 41 such as a CVD apparatus.

  Next, as shown in FIG. 3B, a mask 39 for forming a two-dimensional diffraction grating for the photonic crystal structure is formed on the insulating film 37. This mask is formed by, for example, electron beam lithography. The mask 39 has, for example, a pattern for a two-dimensional lattice. As the two-dimensional lattice, for example, a triangular lattice, a square lattice, or the like is known. The insulating film 37 is etched using the mask 39 to form a plurality of insulators 37a. The plurality of insulators 37 a are periodically arranged in a two-dimensional manner on the main surface 33 a of the gallium nitride based semiconductor layer 33. After the etching, the mask 39 is removed. The period of the two-dimensional grating is related to the lasing wavelength.

  Thereafter, as shown in FIG. 3C, for example, an array of columnar insulating members is embedded with a gallium nitride based semiconductor. This buried growth is performed using, for example, the OMVPE apparatus 21. A gallium nitride based semiconductor layer 43 is grown for filling. The gallium nitride based semiconductor layer 43 is selectively epitaxially grown on the main surface 33a of the gallium nitride based semiconductor layer 33. As a result, the array of insulator columns is buried. The main surface 43a of the gallium nitride based semiconductor layer 43 has a Ga surface. The gallium nitride based semiconductor layer 43 is, for example, p-type. The gallium nitride based semiconductor layer 43 can be made of GaN, AlGaN, InGaN, or a mixed crystal thereof. A periodic array of insulating members embedded in a gallium nitride based semiconductor provides a two-dimensional periodic refractive index change.

  Through these steps, the second semiconductor structure 45 was formed on the substrate 23. In the above embodiment, the second semiconductor structure 45 includes the gallium nitride based semiconductor layers 25, 27, 29, 31, 33, 43, and the array 47 of insulator pillars. The main surface 45a (main surface 43a) of the second semiconductor structure 45 has a Ga surface and is used as a bonding surface as will be described later.

  FIG. 4 is a schematic view showing main steps for fusing the first semiconductor structure and the second semiconductor structure. As shown in FIG. 4A, a substrate product W2 including a second semiconductor structure 45 having a main surface 45a made of a Ga surface is prepared for fusion, and a main surface made of an N surface. A substrate product W1 is prepared which includes a first semiconductor structure 19 having 19a. The main surface (Ga surface) 45a of the substrate product W2 and the main surface 19a (N surface) of the substrate product W2 face each other.

  As shown in FIG. 4B, the first semiconductor structure 19 and the second semiconductor structure 45 are arranged so that the main surface (Ga surface) 45a and the main surface 19a (N surface) are in contact with each other. Are arranged in the processing device 49. As heat treatment conditions, for example, the heat treatment temperature is 500 degrees Celsius, the heat treatment atmosphere is in nitrogen, and the heat treatment time is 1 hour. When fusing, pressurization F is performed. By this process, the junction J is formed, and the first and second semiconductor structures 19 and 45 are integrated to form the substrate product W3. In the junction J, the junction surface made of the N surface of the first semiconductor structure 19 and the junction surface made of Ga of the second semiconductor structure 45 are joined to form a fusion part.

  FIG. 5 is a schematic diagram showing main steps for removing a substrate from a substrate product and forming electrodes. As shown in FIG. 5A, the substrate (for example, the substrate 13) is removed from the substrate product W3. This removal is performed by, for example, laser lift-off. The sacrificial layer 14 is irradiated with a laser through the sapphire substrate 13 to melt the sacrificial layer 14, and the substrate 13 is separated from the substrate product W3. The removal of the substrate is not limited to the illustrated laser lift-off, and etching, polishing, or the like can be used. After removing the substrate 13 from the substrate product W3, the molten product is processed, for example, polished to form an electrode to form a substrate product W4.

  Next, as shown in FIG. 5B, the electrode 53a is formed on the anode surface 51a of the substrate product W4, and the electrode 53b is formed on the cathode surface 51b of the substrate product W4. Through these steps, the gallium nitride based semiconductor surface light emitting device 55 was formed. The gallium nitride based semiconductor surface light emitting device 55 receives the laser light L that is laser-resonated by the two-dimensional diffraction grating layer 54 including a structure in which the refractive index changes periodically through the light emitting surface 55a (in this embodiment, the anode surface). Exit.

(Example)
A gallium nitride photonic crystal laser was fabricated. First, a Ga-polar epitaxial substrate including an active layer having a multiple quantum well structure was produced using an n-type GaN substrate by OMVPE. An SiO ₂ thin film for the photonic crystal layer was deposited on the epitaxial substrate. Thereafter, etching was performed using reactive ion etching (RIE) using a mask for the photonic crystal layer. This formed regularly aligned SiO ₂ fine columns. A substrate product was produced by embedding SiO ₂ fine columns with GaN by OMVPE method.

  Next, an N-polar epitaxial substrate was fabricated using a c-plane sapphire substrate by MBE. The sapphire substrate is attached to a molybdenum holder of the MBE apparatus, and the holder is held by a substrate heating apparatus called a manipulator. For epitaxial growth, the manipulator is heated to about 700 degrees Celsius to heat the substrate. In the MBE apparatus, a K cell for supplying Ga, Mg and the like is introduced. The K cell was resistively heated to raise the temperature of the raw material to a high temperature, and each raw material vapor was supplied onto the sapphire substrate. The nitrogen source supplies activated (plasmaized) nitrogen using an RF radical gun that applies a high-frequency magnetic field. The growing epitaxial surface is provided with RHEED for observation.

The Ga cell was heated to the target temperature to generate a Ga flux of about 1.0 × 10 ⁻⁶ Torr. The Mg cell was heated to a target temperature (for example, 315 degrees Celsius). After introducing the sapphire substrate into the MBE growth chamber, the temperature of the sapphire substrate was started to rise. Surface nitriding of the sapphire substrate was performed under a substrate temperature of 800 degrees Celsius and a nitrogen atmosphere. This nitridation was performed for N-polar growth.

  An Mg-doped GaN contact layer and an Mg-doped GaN cladding layer were grown in order. During the growth of these p-type GaN, a diffraction pattern was performed by RHEED, and the growth state was observed. After taking about 2 hours to grow a GaN layer of about 1 μm to produce an epitaxial substrate, all cell shutters were closed to complete the growth. While lowering the substrate temperature, the plasma of nitrogen was also stopped, and the supply of nitrogen gas to the growth chamber was stopped. When the substrate temperature was sufficiently lowered, the holder on which the substrate was placed was taken out of the growth chamber.

  The Ga surface of the substrate product produced by the OMVPE method and the N surface of the epitaxial substrate produced by the placement method in the MBE chamber were fused under load. As the fusing conditions, for example, the temperature is 500 degrees Celsius, the processing atmosphere is in nitrogen, and the processing time is 1 hour.

After fusion, the sapphire substrate was separated using a KrF excimer laser. The laser light applied to the back surface of the sapphire substrate reaches a gallium nitride semiconductor such as GaN through the sapphire substrate. When the laser light is absorbed by GaN, GaN decomposes at the interface and metal gallium remains at the interface. After the laser irradiation, the epitaxial substrate is heated to a temperature higher than the melting point of metal gallium to peel off the sapphire substrate.
To do.

  While the principles of the invention have been illustrated and described in the preferred embodiments, it will be appreciated by those skilled in the art that the invention can be modified in arrangement and detail without departing from such principles. In the present embodiment, the present invention is not limited to the specific configuration disclosed in the present embodiment. We therefore claim all modifications and changes that come within the scope and spirit of the following claims.

FIG. 1 is a schematic diagram showing main steps in a method for producing a first semiconductor structure for a gallium nitride based semiconductor surface light emitting device according to the present embodiment. FIG. 2 is a schematic diagram showing the main steps in the method of manufacturing the second semiconductor structure for the gallium nitride based semiconductor surface light emitting device according to the present embodiment. FIG. 3 is a schematic view showing main steps for producing a photonic crystal structure. FIG. 4 is a schematic view showing main steps for fusing the first semiconductor structure and the second semiconductor structure. FIG. 5 is a schematic diagram showing main steps for removing a substrate from a substrate product and forming electrodes.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 ... Molecular beam epitaxy (MBE) apparatus, 13 ... Substrate, 15, 17, 25, 27, 29, 31, 33, 43 ... Gallium nitride system semiconductor layer, 19 ... First semiconductor structure, 21 ... Organometallic gas Phase growth (OMVPE) apparatus, 23 ... substrate, 35 ... semiconductor stack, 37 ... insulating film, 39 ... mask, 41 ... film forming apparatus, 37a ... multiple insulators, 45 ... second semiconductor structure, 49 ... processing Device, anode surface 51a ..., 51b ... cathode surface, 53a ... electrode, 53b ... electrode, 54 ... two-dimensional diffraction grating layer, 55 ... gallium nitride based semiconductor surface light emitting element, 55a ... light emitting surface, W1, W2, W3, W4 ... Board products

Claims (11)

A first semiconductor structure made of one or a plurality of gallium nitride based semiconductor layers and having a bonding surface;
A second semiconductor structure comprising one or a plurality of gallium nitride based semiconductor layers and having a bonding surface,
One of the bonding surfaces of the first and second semiconductor structures is a Ga surface,
The other of the joint surfaces of the first and second semiconductor structures is an N plane,
A periodic structure for a photonic crystal is provided on the joint surface of the second semiconductor structure,
The bonding surface of the first semiconductor structure and the bonding surface of the second semiconductor structure are fused to each other;
The gallium nitride based semiconductor surface light emitting device, wherein the second semiconductor structure includes an active layer.   2. The gallium nitride system according to claim 1, wherein the periodic structure for the photonic crystal includes a plurality of voids periodically arranged on the bonding surface of the second semiconductor structure. 3. Semiconductor surface light emitting device.   The periodic structure for the photonic crystal comprises a plurality of insulating members periodically arranged in a gallium nitride based semiconductor of the second semiconductor structure. Gallium nitride semiconductor surface emitting device. The bonding surface of the first semiconductor structure is formed of any one of GaN, AlGaN, InGaN, and mixed crystals thereof,
4. The junction surface of the second semiconductor structure is formed of any one of GaN, AlGaN, InGaN, and a mixed crystal thereof. 2. A gallium nitride based semiconductor surface light emitting device described in 1). A method of fabricating a gallium nitride based semiconductor surface light emitting device including a photonic crystal,
Epitaxially growing a first semiconductor structure comprising one or more gallium nitride based semiconductor layers on a first substrate;
Epitaxially growing a second semiconductor structure comprising one or more gallium nitride based semiconductor layers on a second substrate;
Forming a periodic structure for a photonic crystal in one of the first and second semiconductor structures;
After forming the periodic structure, the main surface of the first semiconductor structure and the main surface of the second semiconductor structure face each other, and are fused.
After the fusion, removing any one of the first and second substrates,
The main surface of the first semiconductor structure has either a Ga surface or an N surface;
The main surface of the second semiconductor structure has either the Ga surface or the N surface;
The method of claim 2, wherein the second semiconductor structure includes an active layer. A main surface of the first semiconductor structure is an N surface;
6. The method according to claim 5, wherein the gallium nitride based semiconductor layer of the first semiconductor structure is formed using a molecular beam epitaxy method. The second semiconductor structure includes an active layer;
7. The method according to claim 5, wherein the gallium nitride based semiconductor layer of the second semiconductor structure is formed using metal organic vapor phase epitaxy.   8. The periodic structure for the photonic crystal comprises a plurality of openings periodically arranged on the main surface of the second semiconductor structure. The method according to one item.   5. The periodic structure for the photonic crystal is composed of a plurality of insulating members periodically arranged in a gallium nitride semiconductor on the main surface of the second semiconductor structure. A method as claimed in any one of the preceding claims. The main surface of the first semiconductor structure is formed of any one of GaN, AlGaN, InGaN and mixed crystals thereof,
The main surface of the second semiconductor structure is formed of any one of GaN, AlGaN, InGaN, and a mixed crystal thereof. The method described in. The first substrate is a sapphire substrate;
A main surface of the first semiconductor structure is an N surface;
The method of claim 5, further comprising nitriding a surface of the sapphire substrate before growing the first semiconductor structure on the first substrate. The method as described in any one.

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