JP4965293B2 - Semiconductor light emitting device, illumination device using the same, and method for manufacturing semiconductor light emitting device - Google Patents

Description

  The present invention relates to a semiconductor light emitting device configured using a compound semiconductor light emitting element such as a III-V compound semiconductor, and further to an illumination device configured using the semiconductor light emitting device and a method for manufacturing the semiconductor light emitting device. The element relates to a device composed of a nanoscale columnar crystal structure called nanocolumn or nanorod.

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 sapphire substrate is used, and an n-cladding layer and a contact layer composed of an n ⁺ -GaN layer doped with silicon (Si) at the lower portion of the light emitting layer, and magnesium ( An electron block layer made of p-Al _x Ga _1-x N doped with Mg) and a p-GaN contact layer are formed on the electron block layer. 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, after forming an n-type GaN buffer layer on a sapphire substrate, a large number of the columnar crystal structures (nanocolumns) arranged in an array are formed, and columnar crystals are formed between the GaN nanocolumns. A transparent electrode and an electrode pad are formed after embedding a transparent insulating layer for structural protection or the like. In particular, the GaN nanocolumn includes an n-type GaN nanocolumn, an InGaN quantum well, 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.

In addition to the prior art described above, there is also a technique using a columnar crystal structure as an alternative to a conventional phosphor as disclosed in Patent Document 2.
JP 2005-228936 A JP 2006-104411 A

First, in the prior art of Patent Document 1, after forming a nanocolumn on a substrate and then depositing a material to form an electrode on the p-type GaN nanocolumn, the p-type GaN nanocolumn and the n-type are sandwiched between InGaN quantum wells. There is a possibility that the GaN nanocolumn is short-circuited. For this reason, before the electrode formation, the transparent insulator made of SOG, SiO ₂ , epoxy resin or the like is buried between the nanocolumns. However, it is extremely difficult to embed these insulators in a very small gap between nanocolumn arrays of about 100 nm to a desired depth. Specifically, in Patent Document 1, a nanocolumn having a diameter of about 70 nm and a height of about 1 μm is manufactured, but the gap aspect ratio (depth / diameter) exceeds 10. It is extremely difficult to completely fill this with CVD or the like, and in Patent Document 1, a liquid insulating material is formed by spin-coating a liquid, but the surface tension works and the gap is well formed. It is difficult to insert.

  On the other hand, the prior art of Patent Document 2 has a configuration in which the diameter of the columnar crystal is 3 nm or less and the length of the light emitting region is 3 nm or less, and the shape uses a columnar crystal structure. It should be called. In other words, this conventional technology originally meant that only quantum dots having a quantum size effect with a diameter of 3 nm and a length of 3 nm were produced as light-emitting elements, but because they could not be produced alone, columnar crystal structures were used. In this, quantum dots are realized. However, it is still very difficult to produce a columnar crystal structure with a diameter of 3 nm, the manufacturing cost must be high, and even if mass-produced, it is very expensive and cannot be used for general lighting.

  As for the light emission mechanism, in this prior art, carriers excited in light absorption regions adjacent to each other are recombined in the light emission region to emit light, that is, light is emitted by photoexcitation.

  An object of the present invention is to provide a semiconductor light-emitting device that can be manufactured inexpensively and stably while avoiding the difficulty of the electrode forming process of the nanocolumn LED and without using a difficult and expensive technology such as a quantum dot. An illumination device using the same and a method for manufacturing a semiconductor light emitting device are provided.

The semiconductor light-emitting device of the present invention is a semiconductor light-emitting device using a columnar crystal structure, wherein the columnar crystal structure is formed of a compound semiconductor having a columnar core portion made of a compound semiconductor having a larger band gap energy than the core portion. It is formed in a coaxial shape surrounded by a cylindrical shell portion and mounted in a state parallel to the support substrate, and the support substrate is made of a conductive substrate, which is behind the columnar crystal structure in the surface layer portion. portion becomes the first electrode through the deep layer, and the other portion becomes the insulating, transparent organic to the cover over the support board having columnar crystal structure, the light generated in the previous SL columnar crystal structure characterized in that it comprises a second electric pole made of metal.

According to another aspect of the present invention, there is provided a method for manufacturing a semiconductor light-emitting device, wherein a columnar core portion made of a compound semiconductor is grown on a growth substrate in the method for manufacturing a semiconductor light-emitting device using a columnar crystal structure. Forming the columnar crystal structure in a coaxial shape surrounded by a cylindrical shell portion made of a compound semiconductor having a larger band gap energy than the portion, and then removing the growth substrate and taking out the columnar crystal structure; A step of dispersing the columnar crystal structures on a conductive support substrate so as to be parallel to the support substrate; and a support substrate on which the columnar crystal structures are mounted are self-aligned to form the surface layer portion Yin become part of the columnar crystal structures in the first electrode through the deep layer, treating the other portion serving as the negative to the insulation, the supporting board having the columnar crystal structure, before Symbol columnar Covered with a transparent organic metal to light generated in the crystal structure, characterized in that it comprises a step of the second electrode.

  According to the above configuration, in the semiconductor light emitting device and the manufacturing method thereof using a nanoscale columnar crystal structure called a nanocolumn or a nanorod, the columnar crystal structure is a hexagonal column made of a compound semiconductor, A rectangular columnar core part is formed as a coaxial heterostructure surrounded by a cylindrical shell part made of a compound semiconductor having a larger band gap energy than the core part. The shell part is a quantum well wall, and the core part is a quantum well. As the bottom of the well, a quantum well is formed with the full length of the columnar crystal structure, separated from the growth substrate after growth, mounted in a rollover state in parallel with a new support substrate, and an electrode is formed on the outer peripheral surface thereof. Then, electrons and holes are injected, stored in the core, and recombined with light emission.

And it is practically impossible to form electrodes on each of the columnar crystal structures to be mounted in a rollover state at any position as described above when sprayed on the support substrate. Therefore, first, the support substrate itself is made conductive so that it becomes the first electrode. Further, it is possible to the second electrode by the previous SL transparent organometallic against the light generated in the columnar crystal structure is coated with spin coating to cover the columnar crystal structure.

  However, if the columnar crystal structures are spread on the support substrate and then covered with an organic metal as it is, the first electrode and the second electrode will be short-circuited. Using the self-alignment by the columnar crystal structure, the surface layer portion of the support substrate is processed to be divided into a region that becomes the first electrode and a region that does not have the insulating property. For example, when the support substrate is made of aluminum, by nitriding, the shadowed part of the columnar crystal structure remains aluminum, and the outer peripheral edge and the back surface are used as terminals to the power supply through the deep layer. Can do. On the other hand, except for the shaded portion, it becomes aluminum nitride and becomes insulating, so that the short circuit does not occur even if the organic metal is covered.

  Therefore, since the difficulty of electrode formation is eliminated, it is possible to realize a semiconductor light emitting device that can be manufactured at a very low cost and stably and a manufacturing method thereof. Further, even when viewed as a single columnar crystal structure, although there is no pn junction and the injection efficiency of electrons and holes is poor, almost the entire length can be used as a quantum well, so that the emission area can be overwhelmingly widened.

  Furthermore, in the semiconductor light emitting device of the present invention, the support substrate is made of aluminum.

  According to the above configuration, when the support substrate is made of aluminum, the columnar crystal structure made of gallium nitride or the like can be formed by simply forming the good ohmic contact with the n-type layer and oxidizing or nitriding the substrate. The surface layer portion can be made insulative very easily without causing damage, and is suitable as a material for the support substrate.

  In the semiconductor light-emitting device of the present invention, the columnar crystal structure has a plurality of types in which at least the core portion has different compositions.

  According to said structure, the light of a different wavelength can be radiated | emitted by having a different composition of a core part, and the light of desired colors, such as white, can be generated by combining multiple types of them. .

  Furthermore, the illumination device of the present invention is characterized by using the semiconductor light emitting device.

  According to said structure, the illuminating device which can be manufactured stably cheaply is realizable, avoiding the difficulty of the electrode formation process to nanocolumn.

  In the method of manufacturing a semiconductor light emitting device of the present invention, the step of forming the core portion on the growth substrate includes the step of forming a catalyst material layer on the compound semiconductor material on the growth substrate, and the catalyst material. Patterning a layer into a shape corresponding to a column diameter on which the core portion is to be grown, and taking in the compound semiconductor material from the catalyst material layer left by the patterning, and bonding in the catalyst material layer And a step of crystal-growing the core portion on the growth substrate.

  According to the above configuration, for example, when the core portion of the columnar crystal structure is grown on a growth substrate such as sapphire, a compound semiconductor material such as Ga, N, In, or Al, or addition of Mg, Si, or the like A catalyst material layer such as Ni, Cu, Fe, Au or the like that dissolves and takes in a material and does not form a composite with itself is formed on the growth substrate. Thereafter, the catalyst material layer is patterned into a shape corresponding to the column diameter on which the core portion is to be grown to grow the core portion.

  Therefore, a large amount of core portions having a desired shape can be produced. After the core portion has grown to a desired length, growth is started around the core portion by changing the material composition and growth temperature, and the cylindrical shell portion is obtained.

As described above, the semiconductor light-emitting device and the manufacturing method thereof according to the present invention are the above-described columnar crystal structure in the semiconductor light-emitting device and the manufacturing method thereof using a nanoscale columnar crystal structure called a nanocolumn or a nanorod. The shell portion is formed as a coaxial heterostructure in which a body is surrounded by a cylindrical shell portion made of a compound semiconductor having a band gap energy larger than that of the core portion. The quantum well is formed with the full length of the columnar crystal structure with the quantum well wall and the core as the bottom of the quantum well, separated from the growth substrate after growth, and mounted in a rollover state parallel to a new support substrate Then, an electrode is formed on the outer peripheral surface to inject electrons and holes, and the electrons are stored in the core portion to recombine light emission. Further , after such a columnar crystal structure is dispersed on a conductive support substrate, the surface layer portion of the support substrate is made to be a region serving as the first electrode by using self-alignment by the columnar crystal structure. not subjected to processing for division into an insulating and a region, first by pre-SL transparent organometallic to light generated in the columnar crystal structure is coated with spin coating to cover the columnar crystal structure 2 electrode.

  Therefore, it is possible to realize a semiconductor light emitting device and a method for manufacturing the semiconductor light emitting device that can be manufactured stably at an extremely low cost because the difficulty of electrode formation is eliminated. Further, even when viewed as a single columnar crystal structure, although there is no pn junction and the injection efficiency of electrons and holes is poor, almost the entire length can be used as a quantum well, so that the emission area can be overwhelmingly widened.

  Furthermore, in the semiconductor light emitting device of the present invention, the support substrate is made of aluminum as described above.

  Therefore, it is excellent in heat dissipation, forms a good ohmic contact with the n-type layer, and is very easy to oxidize or nitride without causing damage to the columnar crystal structure made of gallium nitride or the like. Can be made insulative, and is suitable as a material for the support substrate.

  In addition, as described above, the semiconductor light-emitting device of the present invention uses a plurality of types of the columnar crystal structure having at least the core portion different in composition.

  Therefore, light of different wavelengths can be emitted, and light of a desired color such as white can be generated by combining a plurality of types of light.

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

  Therefore, it is possible to realize an illumination device that can be manufactured stably at low cost while avoiding the difficulty of the electrode forming process on the nanocolumn.

  In addition, as described above, in the method for manufacturing a semiconductor light emitting device of the present invention, when the core portion of the columnar crystal structure is grown on a growth substrate such as sapphire or Si, Ga, N, In, Al Growth of catalyst material layers such as Ni, Cu, Fe, Au, etc. that dissolve and take in compound semiconductor materials such as Mg, Si, etc. It is formed on a substrate, and then the catalyst material layer is patterned into a shape corresponding to the column diameter on which the core portion is to be grown, thereby growing the core portion.

  Therefore, a large amount of core portions having a desired shape can be formed.

FIG. 1 is a perspective view showing a part for explaining the structure of a semiconductor light emitting device 1 according to an embodiment of the present invention. It should be noted that in this semiconductor light emitting device 1, the nanocolumns 2a, 2b, 2c, 2d, 2e, 2f, and 2g (generally referred to as reference numeral 2 hereinafter) are formed from a growth substrate (not shown). after being separated, numerous sprayed on a supporting substrate 3 having an electrically conductive, it is that the sealing member 4 made of a transparent organic metal to light generated in the burner Nokoramu 2 is constructed is covered. It should also be noted that the nanocolumn 2 includes a cylindrical core portion 21 made of a compound semiconductor having a band gap energy larger than that of the core portion 21, as shown in FIG. It is formed in an enclosed coaxial heterostructure, and the core portion 21 itself becomes an active layer.

  That is, for example, the core portion 21 is made of n-type GaN, the shell portion 22 is made of n-type AlGaN, the shell portion 22 is a quantum well wall, and the core portion 21 is a bottom of the quantum well. A quantum well is formed over the entire length of the nanocolumn 2. Therefore, as will be described later, electrons and holes injected from the outer peripheral surface of the nanocolumn 2 are stored in the core portion 21 and recombine by light emission. The light generated thereby cannot activate the shell portion 22 having a large band gap energy, passes through the shell portion 22, and further passes through the sealing member 4 made of the transparent organic metal. Released to the outside.

  FIG. 3 is a cross-sectional view schematically showing a manufacturing process of the nanocolumn 2. In the present embodiment, photolithography is used to form the nanocolumns 2. However, the formation method is not limited to this method, and it is needless to say that a method such as electron beam exposure may be used. . In this embodiment, it is assumed that the growth of the nanocolumn 2 is performed by metal organic chemical vapor deposition (MOCVD). However, the growth method of the nanocolumn 2 is not limited to this, and molecular beam epitaxy ( The nanocolumn 2 can also be fabricated using MBE) or hydride vapor phase epitaxy (HVPE) method. Hereinafter, an MOCVD apparatus is used unless otherwise specified.

  First, on a growth substrate 31 made of sapphire, a Ni thin film 32 serving as a catalyst material layer is deposited to a thickness of about 10 nm by electron beam evaporation, and then the Ni thin film 32 is formed by using a normal lithography technique and a dry etching technique. Then, patterning is performed at appropriate intervals in an island shape having a diameter of 10 to 100 nm, as shown in FIG.

Subsequently, this is put in an MOCVD apparatus, the temperature is set to 950 ° C., and n-type impurities are supplied to TMG (trimethylgallium) and NH ₃ (ammonia) as growth gases for GaN crystal growth while maintaining this temperature. When SiH ₄ (silane) and hydrogen as a carrier gas are further supplied, the core portion 21 made of the n-type GaN nanocolumn is 1 μm by GaN nanocolumn growth using a conventionally known catalyst, and FIG. ) Grow as shown.

Thereafter, in a nitrogen atmosphere where the carrier gas is changed from hydrogen to nitrogen, the formation temperature is set to 940 ° C., and TMA (trimethyl) is further added as a growth gas to the TMG (trimethylgallium), NH ₃ (ammonia) and SiH ₄ (silane). By adding (aluminum), the shell portion 22 made of an n-type AlGaN layer grows with a thickness of 10 nm or less as shown in FIG. In this way, a large number of nanocolumns 2 having a desired diameter and length can be produced.

  As shown in FIG. 3 (d), the nanocolumn 2 created in this way is detached from the growth substrate 31 by immersing the entire growth substrate 31 in an alcohol 34 filled in a container 33 and applying ultrasonic waves (root). From the alcohol 34. Thereafter, the sapphire substrate 31 is removed from the container 33, and the support substrate 3, which is a device support substrate in which an Al substrate 5 serving as an n-type electrode and a Cu substrate 6 serving as an n-type electrode terminal are stacked, is placed in the container 33. By evaporating the alcohol 34, a large number of nanocolumns 2 can be mounted on the support substrate 3 as shown in FIG. Alternatively, the support substrate 3 is first put in the container 33, and the growth substrate 31 is turned upside down and the ultrasonic wave is applied, so that the nanocolumn 2 peeled off from the sapphire substrate 31 falls on the support substrate 3. Thereafter, the growth substrate 31 may be removed, and the alcohol 34 may be evaporated. In this state, the nanocolumn 2 can be alloyed and fixed on the support substrate 3 by annealing in a furnace at around 400 ° C.

  Thereafter, as shown in FIG. 4, when the nitrogen radicals 35 are irradiated from above the support substrate 3, the nanocolumns 2 scattered at an arbitrary position are self-aligned with the nanocolumns 2 in the surface layer portion of the Al substrate 5. The non-shadowed portion 5a is nitrided to form an aluminum nitride layer. This is an insulator layer, and it plays a role of separating the Al substrate 5 from the sealing member 4 which will be formed in the upper part in the future and will be a p-type electrode. On the other hand, the shaded portion 5 b of the nanocolumn 2 is not nitrided and has conductivity, and connects the shell portion 22 and the Cu substrate 6 from the deep layer portion of the Al substrate 5. By using the Al substrate 5 in this manner, heat dissipation is excellent, and a good ohmic contact with the n-type layer of the shell portion 22 is formed, and the nanocolumn 2 made of GaN is damaged only by oxidation or nitridation. Therefore, the surface layer portion can be made insulative very easily and is suitable as a material for the support substrate 3.

  Subsequently, as shown in FIG. 5, the sealing member 4 made of the transparent organic metal is spin-coated, for example, by 300 nm on the entire surface of the support substrate 3, and then ITO 7 is deposited, and Au is partially deposited on the upper part. When the p-type electrode terminal 8 made of is formed, the semiconductor light emitting device 1 is completed.

The growth substrate 1 is not limited to sapphire, but silicon (Si), silicon carbide (SiC), aluminum nitride (AlN), aluminum oxide (Al ₂ O ₃ ), silicon oxide (SiO ₂ ), zinc oxide (ZnO), etc. May be used. Needless to say, the crystal of the nanocolumn 2 is not limited to GaN but may be an oxide such as ZnO or an oxynitride material. Furthermore, the nanocolumn 2 is not limited to the n-type, but is a coaxial nanocolumn composed of a p-type core part and a p-type shell part surrounding the p-type core part, and the band gap energy width of the p-type core part is the band gap of the p-type shell part. If it is smaller than the energy width, light can be emitted by the same mechanism.

  However, the compound semiconductor material and additive material and the catalyst material layer need to be selected as materials in which the catalyst material layer dissolves and takes in the compound semiconductor material and additive material and does not form a composite. For example, the catalyst material layer is Ni, Cu, Fe, Au, etc., the compound semiconductor material is Ga, N, In, Al, etc., and the additive material is Mg, Si, etc. Further, the thin film of the catalyst material layer has a thickness capable of exhibiting a function as a catalyst material layer for taking in the material, for example, from several atomic layers to a thickness at which the taken-in material can diffuse, for example, 20 nm. Preferably, the thickness is 10 nm.

  Further, in the above example, the catalyst material layer is used in forming the nanocolumn 2. However, the compound semiconductor material such as Ga, N, In, Al or the like on the growth substrate 31 such as silicon (Si), Mg A seed crystal layer of AlN or the like that grows on the core portion 21 by adsorbing and bonding these elements to additive materials such as Si and Si may be used.

  In this way, a large amount of nanocolumns 2 having a desired shape can be produced. Then, by patterning the Ni thin film 32 serving as the catalyst material layer into a shape corresponding to the column diameter to be grown, the respective emission wavelengths and the like can be adjusted. Further, by mixing a plurality of types of nanocolumns 2 having different compositions (band gap widths of the core portion 21) in the container 33, for example, red (R), green (G), blue (B ) Can be combined to generate white light, and by changing their content, light of a desired color can be generated. Color is one of the important specifications in the lighting field, and it is possible to design it freely in this way.

  In the semiconductor light emitting device 1 configured as described above, for example, the core portion 21 has a diameter of 10 to 100 nm and the shell portion 22 has a thickness of about 10 nm or less. Therefore, the current that has passed through the p-type electrode terminal 8, the ITO 7, and the sealing member 4 from the external power supply immediately passes through the shell portion 22 in the thickness direction, passes through the core portion 21, and then passes through the shell portion 22 on the support substrate 31 side again. It flows in the thickness direction and flows to the support substrate 3. As a result, holes are injected from the sealing member 4 where electrons are originally accumulated in the core portion 21, and luminescence recombination occurs. The generated light is efficiently extracted into the atmosphere through the sealing member 4 and the ITO 7.

  With this configuration, in the semiconductor light emitting device 1 according to the present embodiment, since it is not difficult to form electrodes on the nanocolumns 2, it can be manufactured at a very low cost and stably. In addition, even when the nanocolumn 2 is viewed as a single unit, there is no pn junction and the injection efficiency of electrons and holes is poor, but either the + or − electrode is formed over the entire circumference, and the total length of the nanocolumn 2 is Can be used as a quantum well, so that the emission area can be overwhelmingly widened.

  In FIG. 1, the nanocolumns 2a, 2b, 2c, 2d, and 2e that are in close contact with the support substrate 3 emit light, but the nanocolumns 2f and 2g that ride on the other nanocolumns 2b and 2e have shell portions 22. Depending on the contact condition, there is a case where no light is emitted particularly on the leading end side. However, light generated in the lower nanocolumns 2b and 2e may be absorbed by the core portion 21 of these nanocolumns 2f and 2g and re-emitted, and the underlying nanocolumns 2b and 2e are covered. , 2g is not necessarily shaded (light is emitted through the covering nanocolumns 2f, 2g).

  Here, in non-patent literature (Fang Qian; Silvija Gradcak; Yat Li; Cheng-Yen; Charles M. Lieber; Nano lett. 2005 vol.5 No.11 2287-2291), the nanocolumn is axially oriented on the growth substrate. After growing, the quantum well is formed in the radial direction, separated from the growth substrate after the growth, mounted in a rollover state parallel to a new support substrate, and an electrode is attached. It is shown to emit light.

  FIG. 6 is a perspective view showing the structure of the nanocolumn 41 in the prior art. In this nanocolumn 41, first, an n-type GaN core layer 42 is grown on a non-polar a-plane on a growth substrate (not shown) in a triangular prism shape, and then the growth gas and temperature are changed to change the non-doped InGaN shell layer 43, This is a heterostructure-type nanocolumn grown in a coaxial shape in the order of a non-doped GaN layer 44, a p-type AlGaN layer 45, and a p-type GaN layer 46.

  The nanocolumn 41 is also separated from the growth substrate and dispersed on a new support substrate 47 as shown in FIG. 7, and then folded as indicated by reference numerals 41a and 41b, or reference numerals 41c and 41d. As shown by the reference numeral 41e, except for those at the periphery, those that are not folded and have a space for forming the p-type electrode 48 and the n-type electrode 49 are selected. The electrodes 48 and 49, the pattern 50, and the pad 51 are formed on the top by electron beam drawing or the like. A portion indicated by hatching where the p-type electrode 48 and the nanocolumn 41e are overlapped is a light emitting region. Note that the surface p-type GaN layer 46 has a high resistance, and most of the current flowing between the electrodes 48 and 49 immediately passes through the p-type GaN layer 46 in the thickness direction, as indicated by reference numeral 52, and the low resistance. The current that flows through the n-type GaN core layer 42 and shorts the p-type GaN layer 46 seems to be small.

  This configuration has the advantage that the internal quantum efficiency is increased by eliminating the internal piezoelectric field by having the a-axis in the longitudinal direction. In addition, since the light emitting layer (the hatched portion) serving as a heat source is located near the support substrate 47 serving as a heat sink, it has an advantage of excellent heat dissipation and a reduction in external quantum efficiency even at high output.

  On the other hand, in the present embodiment, the core portion 21 is grown in the c-axis direction, which is easy to grow. However, since the direction of current flow is a coaxial radial direction orthogonal to the core portion 21, the non-patent As in the literature, it is possible to cancel out the piezo electric field, realize high internal quantum efficiency (can increase luminescence recombination efficiency), and realize high injection efficiency. Similarly, since the nanocolumn 2 is parallel to the support substrate 3, the heat dissipation is the same.

However, in the non-patent literature, a very expensive SiC substrate or LiAlO ₂ substrate is required for the growth of the a-plane, whereas in this embodiment, inexpensive sapphire can be used. .

  In addition, in the non-patent literature, when forming the electrodes 48 and 49, a tremendous work of searching for a nanocolumn 41e in a good state with an SEM and drawing using an electron beam as described above is required. In addition, since the electrodes 48 and 49, the pattern 50, and the pad 51 are pasted around the nanocolumn 41e, a large space is required and wiring is complicated on the support substrate. Of the nanocolumns 41 dispersed on the support substrate 47, only a small amount of light is actually emitted. Further, as described above, light is actually emitted from the p-type electrode 48 and the nanocolumn 41e that are overlapped with each other. For this reason, there exists a problem that an output is too small and cannot be used for the use which requires high output, such as a lighting application. On the other hand, in the present embodiment, as described above, the electrodes can be formed extremely easily and collectively for all the nanocolumns 2 on the support substrate 3, and around the nanocolumns 2. A large space is not required, and a large number of nanocolumns 2 can be accommodated on the support substrate 3, and the light emission area is wide, so that the amount of light can be increased. Thereby, the possibility of lighting application is very high.

  Therefore, the prior art of non-patent literature is an epoch-making technique in which a heterostructure is formed in a coaxial radial direction and the nanocolumn 41 is used in a parallel rollover state on a support substrate 47. It is a level technology and cannot be mass-produced industrially.

1 is a perspective view showing a part for explaining the structure of a semiconductor light emitting device according to an embodiment of the present invention. It is a perspective view of the nanocolumn used for the said semiconductor light-emitting device. It is sectional drawing which shows the manufacturing process of the said nanocolumn typically. It is sectional drawing which shows the manufacturing process of the said semiconductor light-emitting device typically. It is sectional drawing which shows the completion state of the said semiconductor light-emitting device typically. It is a perspective view of the prior art nanocolumn which formed the heterostructure in the radial direction of the coaxial shape. It is a perspective view which shows the structure of the semiconductor light-emitting device of the prior art which used the nanocolumn in the parallel state on the support substrate.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Semiconductor light-emitting device 2, 2a, 2b, 2c, 2d, 2e, 2f, 2g Nanocolumn 3 Support substrate 4 Sealing member 5 Al substrate 6 Cu substrate 7 ITO
8 p-type electrode terminal 21 core part 22 shell part 31 growth substrate 32 Ni thin film 33 container 34 alcohol 35 nitrogen radical

Claims (6)

In a semiconductor light emitting device using a columnar crystal structure,
The columnar crystal structure is formed in a coaxial shape in which a columnar core portion made of a compound semiconductor is surrounded by a cylindrical shell portion made of a compound semiconductor having a band gap energy larger than that of the core portion, and is parallel to a support substrate. It is installed in the state,
The support substrate is made of a conductive substrate, and the portion of the surface layer that is the shadow of the columnar crystal structure becomes the first electrode through the deep layer portion, and the other portion is insulative,
The semiconductor light emitting device which comprises a second conductive electrode formed of a transparent organic metal to the cover supporting the upper board having columnar crystal structure, the light generated in the previous SL columnar crystal structure.   2. The semiconductor light emitting device according to claim 1, wherein the support substrate is made of aluminum.   3. The semiconductor light emitting device according to claim 1, wherein the columnar crystal structure has a plurality of types in which at least the core portion is composed of different compositions.   An illumination device using the semiconductor light emitting device according to claim 1. In a method for manufacturing a semiconductor light emitting device using a columnar crystal structure,
A columnar core portion made of a compound semiconductor is grown on a growth substrate, and the core portion is surrounded by a cylindrical shell portion made of a compound semiconductor made of a compound semiconductor having a larger band gap energy than the core portion. After forming the body, peeling the growth substrate and removing the columnar crystal structure;
Conductive the columnar crystal structure on a supporting substrate, a step of spraying so as to be parallel to the support substrate,
The supporting substrate on which the columnar crystal structure is mounted is made self-aligned so that the shadowed portion of the columnar crystal structure on the surface layer portion is made into the first electrode through the deep layer portion, and the portions other than the shadowed portion are made insulative. Processing step;
A support board having the columnar crystal structure, before Symbol covered with a transparent organic metal to light generated in the columnar crystal structure, the semiconductor light-emitting device which comprises a step of the second electrode Manufacturing method. Forming the core on the growth substrate,
Forming a catalyst material layer for the compound semiconductor material on the growth substrate;
Patterning the catalyst material layer into a shape corresponding to the column diameter on which the core portion is to be grown;
A step of incorporating the compound semiconductor material from the catalyst material layer left by the patterning and bonding the compound semiconductor material in the catalyst material layer to crystal-grow the core portion on the growth substrate. A method for manufacturing a semiconductor light emitting device according to claim 5.

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