JP5112761B2 - COMPOUND SEMICONDUCTOR ELEMENT, LIGHTING DEVICE USING SAME, AND METHOD FOR PRODUCING COMPOUND SEMICONDUCTOR ELEMENT - Google Patents

Description

  The present invention relates to a compound semiconductor element such as a III-V compound semiconductor, a lighting device using the compound semiconductor element, and a method for manufacturing the compound semiconductor element. In particular, the semiconductor element includes a nanoscale nanocrystal or nanorod on a substrate. The present invention relates to a structure in which a columnar crystal structure 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. The structure of this light-emitting element is mainly composed of an n-cladding layer and contact layer made of an n ⁺ -GaN layer doped with silicon (Si) at the lower part of the light-emitting layer, and magnesium (Mg) at the upper part of the light-emitting layer. ) Doped p-Al _x Ga _1-x N, and a p-GaN contact layer is formed on the electron block layer. These planar light emitting devices (LEDs) have a large difference in lattice constant between the sapphire of the substrate and the nitride or oxide semiconductor layer and are formed as a thin film on the substrate. Therefore, 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 blue GaN nanocolumn is composed of an n-type GaN nanocolumn, an InGaN quantum well, and a p-type GaN nanocolumn.

In this GaN nanocolumn LED, unlike the planar LED, the growth nuclei scattered during the growth of the GaN epilayer are bonded in the lateral (plane) direction and then grown in the vertical direction on the plane. Is grown in the vertical direction before bonding in the lateral (plane) direction, so threading dislocations do not exist in principle, and point defects generated around threading dislocations are overwhelmingly less than in the planar type. I can expect. For this reason, it is expected that a GaN single crystal having an extremely good crystal quality as compared with the planar type LED can be obtained, and the internal quantum efficiency can be drastically improved.
JP 2005-228936 A

In the nanocolumn LED configured as described above, the problem of threading dislocation has been solved. However, as a drawback to the planar type LED, in the formation of the p-type electrode, it is difficult to fill the insulator between the nanocolumns. It has the disadvantage that it is difficult to form electrodes. That is, when the p-type electrode is formed on the p-type GaN layer formed at the tip of the nanocolumn, the electrode material enters between the nanocolumns, and the very thin p-type GaN layer is separated from the active layer and the n-type GaN layer. Leaks or shorts will occur. For this reason, after forming the nanocolumn on the substrate, a transparent insulator such as SOG, SiO ₂ , or epoxy resin is embedded by spin coating or the like, and the p-type electrode is formed thereon. However, the surface tension acts on the liquid transparent insulator, and it is difficult to put it into the gap between the nanocolumns even using the spin coating.

  The objective of this invention is providing the compound semiconductor element which can form an upper electrode easily, the illuminating device using the same, and the manufacturing method of a compound semiconductor element.

The compound semiconductor device of the present invention is formed on the substrate or buffer layer connected to the first conductivity type electrode in the compound semiconductor device having a plurality of nanoscale columnar crystal structures on the substrate or buffer layer, An insulating film having an opening for growing the columnar crystal structure, and an organic metal having translucency and having a second conductivity type opposite to the first conductivity type; made, is connected to the second conductivity type electrode, said saw including a sealing member for sealing a columnar crystal structure, said columnar crystal structure comprises a core portion indicating said first conductivity type, the It is formed in a coaxial shape surrounding a core portion and having a shell portion showing the first conductivity type, and the magnitudes of their band gap energies are different from each other .

Also, the method for producing a compound semiconductor element of the present invention is to be connected to an electrode of the first conductivity type in the method for producing a compound semiconductor element having a plurality of nanoscale columnar crystal structures on a substrate or a buffer layer. An insulating film is formed on the substrate or buffer layer, and the insulating film is patterned into a shape corresponding to a column diameter to be grown at a position where the columnar crystal structure is to be grown. A step of forming an opening so that the buffer layer is exposed; a step of growing the columnar crystal structure with the first conductivity type from the substrate or the buffer layer exposed in the opening; The columnar crystal structure is a sealing member made of an organic metal having a second conductivity type opposite to the first conductivity type and connected to an electrode of the second conductivity type. A step of sealing the body seen including, the step of crystal growth of the columnar crystal structures, the first growing a core part showing a conductivity type, the core portion and the mutually different sizes of band Growing a shell portion having the first conductivity type in a coaxial shape having gap energy and surrounding the core portion .

According to the above configuration, a compound in which a large number of nanoscale columnar crystal structures called nanocolumns or nanorods are grown on a substrate or a buffer layer required for the presence or absence of conductivity and crystal growth. In growing a columnar crystal structure in a semiconductor device and its manufacturing method, an insulating film made of SiO ₂ , SiN or the like is formed, and a column diameter to be grown at an arrangement position where the columnar crystal structure is to be grown The insulating film is patterned into a shape corresponding to the above, and an opening is formed so that the substrate or the buffer layer is exposed. Thereafter, the first conductivity type of the substrate or the buffer layer and the columnar crystal structure is made of an organic metal exhibiting a second conductivity type opposite to the first conductivity type, and has a light-transmitting property. The columnar crystal structure is sealed by depositing and baking a sealing member connected to the conductive type electrode.

  Accordingly, a pn junction is formed between the outer peripheral surface of the columnar crystal structure and the sealing member to emit light at the interface, while the substrate or buffer layer that is the first conductivity type and the second conductivity are formed. It is insulated from the sealing member, which is a mold, by the insulating film, and even if there is insufficient filling of the organic metal by the spin coating or the like, it is possible to prevent leakage and short-circuiting and improve reliability. be able to. Further, the upper electrode can be easily formed on the sealing member.

  Further, the opening, and therefore the arrangement of the columnar crystal structures, that is, the arrangement pitch and arrangement pattern, and the column diameter can be arbitrarily set. For example, in the case of a light emitting device, the advantages of the columnar crystal structure with few crystal defects are obtained. In addition to being able to efficiently extract the generated light to the outside, it is possible to realize optical characteristics as intended by the designer, such as extraction with a desired light distribution. Further, by adjusting the column diameter, light having a desired wavelength can be generated, and light of a desired mixed color, for example, white light can be generated.

Further, the columnar crystal structure is formed into a coaxial shape including a core portion and a shell portion having the same first conductivity type, and the magnitudes of the band gap energies thereof are made different from each other to thereby form a quantum well (light emitting layer). Can be formed, and the luminous efficiency can be improved.

  Furthermore, the compound semiconductor device of the present invention dissolves and takes in the compound semiconductor material and additive material between the substrate or the buffer layer and the insulating film, and forms a composite with itself. And a compound seed crystal layer in which the compound semiconductor material and the additive material are adsorbed and bonded to grow into the columnar crystal structure.

  According to the above configuration, when the columnar crystal structure is grown on the substrate or the buffer layer, a compound semiconductor material such as Ga, N, In, or Al, or an additive material such as Mg, Si, or Zn is used. In addition, the columnar crystal structure is formed by adsorbing and binding the catalyst material layer such as Ni, Cu, Fe, Au, etc., and the compound semiconductor material and the additive material which are taken in by dissolving them and do not form a composite with itself. A compound seed crystal layer such as AlN to be grown is formed in advance on the substrate or the buffer layer.

  Therefore, the columnar crystal structure can be grown in a short time.

Also, the illumination device of the present invention is characterized by using the compound semiconductor device.

  According to said structure, while being able to improve the reliability of a light emitting element, the illuminating device which can form easily the upper electrode of the light emitting element is realizable.

  As described above, the compound semiconductor device and the manufacturing method thereof according to the present invention include a compound semiconductor device in which a large number of nanoscale columnar crystal structures called nanocolumns or nanorods are grown on a substrate or a buffer layer, and In the manufacturing method, when growing the columnar crystal structure, an insulating film is formed and patterned to form an opening so that the substrate or buffer layer is exposed, and then the substrate or buffer layer and the columnar structure are formed. It is made of an organic metal having a second conductivity type opposite to the first conductivity type of the crystal structure, has translucency, and is connected to the electrode of the second conductivity type. The columnar crystal structure is sealed by depositing and baking a sealing member.

  Therefore, a pn junction is formed between the outer peripheral surface of the columnar crystal structure and the sealing member to emit light at the interface, while the substrate or buffer layer of the first conductivity type and the second It is insulated from the conductive sealing member by the insulating film, and even if there is insufficient organic metal filling due to the spin coating, etc., it can prevent leaks and shorts, improving reliability can do. Further, the upper electrode can be easily formed on the sealing member.

  Furthermore, the compound semiconductor element of the present invention, as described above, dissolves and takes in the compound semiconductor material and additive material between the substrate or the buffer layer and the insulating film, and Has a catalyst material layer that does not form a composite, or a compound seed crystal layer that grows into the columnar crystal structure by adsorbing and bonding the compound semiconductor material and the additive material.

  Therefore, the columnar crystal structure can be grown in a short time.

Further, the pre-Symbol coaxial shape consisting of a core portion and a clad portion showing the same conductivity type columnar crystal structure, since the different size of their band gap energy from each other, to form a quantum well (light emitting layer) And the luminous efficiency can be improved.

  Furthermore, the illumination device of the present invention uses the compound semiconductor element as described above.

  Therefore, it is possible to improve the reliability of the light emitting element and to realize an illumination device that can easily form the upper electrode of the light emitting element.

[Embodiment 1]
FIG. 1 is a cross-sectional view schematically showing a manufacturing process of a light-emitting diode which is a compound semiconductor element according to the first embodiment of the present invention. In the present embodiment, photolithography is used to form the nanocolumns, but the formation method is not limited to this method, and it goes without saying that a method such as electron beam exposure may be used. In this embodiment, it is assumed that nanocolumn growth is performed by metal organic chemical vapor deposition (MOCVD). However, the nanocolumn growth method is not limited to this, and molecular beam epitaxy (MBE). Nanocolumns can also be fabricated using hydride vapor phase epitaxy (HVPE) or the like. Hereinafter, unless otherwise specified, an MOCVD apparatus is used in this embodiment. Furthermore, although GaN will be described as a nanocolumn crystal, it is not limited thereto, and it goes without saying that oxides, oxynitrides, and other materials are also applicable. Further, although sapphire is used as the insulating substrate and Si is used as the conductive substrate, the invention is not limited thereto, and SiC, SiO ₂ , ZnO, AlN, or the like can also be used.

First, as shown in FIG. 1A, an n-type GaN layer serving as a buffer layer for extracting an n-type electrode is formed on an sapphire substrate 1 which is an insulating substrate by the existing method using the MOCVD apparatus. After 2 μm is grown, the substrate 1 is taken out, and an SiO ₂ thin film 4 as an insulating film is deposited by 50 nm by EB deposition. Thereafter, the opening 5 is formed at a predetermined position with a diameter of, for example, 100 nm using a normal lithography technique and an etching technique.

This is put in an MOCVD apparatus, set to a temperature of 900 ° C., and while maintaining this temperature, TMG (trimethylgallium) and NH ₃ (ammonia), which are growth gases for GaN crystal growth, are supplied and an n-type impurity material When DEZn (diethyl zinc) is supplied in order to dope Zn, the materials of Ga, N, and Zn are shown in FIG. 1B using the n-type GaN layer 2 exposed from the opening 5 as a seed crystal. Thus, the GaN: Zn nanocolumn 6 is grown. Meanwhile, the Ga adsorbed onto SiO ₂ thin film 4, N, Zn is the material, it can not remain long on the surface of the SiO ₂ thin film 4, separated from the surface, on the SiO ₂ film 4 is GaN single Crystals are not formed. Thus, the GaN: Zn nanocolumn 6 grows only in the opening 5. By maintaining this state for about 10 minutes, the GaN: Zn nanocolumn 6 grows to a height of about 100 nm. The concentration of Zn is preferably about 10 ⁻¹⁷ to 10 ⁻¹⁹ .

  Next, an aqueous solution containing organometallic PEDOT: PSS (poly 3,4-ethylenedioxythiophene doped with poly 4-styrenesulfonate) is spin-coated at a rotation speed of 8000 rpm for 60 seconds to deposit about 100 nm in thickness. Thereafter, the p-type layer 7 is formed as shown in FIG. 1C by removing moisture by baking at 120 ° C. for 1 hour on a hot plate.

  Subsequently, as shown in FIG. 1 (d), a Ni 5 nm / ITO 25 nm laminated film, which is a transparent conductive layer, is formed by sputtering deposition to form a p-type transparent electrode 8, and a Ni 30 nm / Au 500 nm laminated film is formed on the p-type transparent electrode 8. The p-type electrode pad 9 is partially formed by ordinary lithography and etching. Thereafter, a portion where an n-type electrode will be formed in the future is etched by ordinary photolithography technology and RIE to expose the n-type GaN layer 2, and Ti 30 nm / Au 500 nm is laminated on this portion by using lift-off technology, and patterned to form an n-type. The electrode 10 is formed.

In the light-emitting diode manufactured as described above, the GaN: Zn nanocolumn 6 grows in close contact with the opening 5 of the SiO ₂ thin film 4, so that the n-type GaN layer 2 connected to the n-type electrode 10. And the p-type layer 7 connected to the p-type transparent electrode 8 are electrically insulated. Here, the energy band gap of the GaN: Zn nanocolumn 6 is 2.6 eV, and the emission wavelength is about 460 nm. On the other hand, the PEDOT: PSS is an organic metal having a property of conducting only holes, and its energy band gap is 3 eV. Therefore, the p-type layer 7 is transparent with respect to the emission wavelength from the GaN: Zn nanocolumn 6, and the GaN: Zn nanocolumn 6 serves as a well layer for carrier recombination emission due to the difference in energy band gap. do.

  With such a configuration, even if there is insufficient filling of the organic metal by spin coating or the like, leakage or short-circuit can be prevented and reliability can be improved. The p-type transparent electrode 8 can be easily formed on the p-type layer 7 which is a sealing member.

  Further, the arrangement of the openings 5, and thus the arrangement of the GaN: Zn nanocolumns 6, that is, the arrangement pitch and arrangement pattern, and the column diameter can be arbitrarily set, and the generated light is efficiently utilized by taking advantage of the nanocolumns with few crystal defects. In addition, the optical characteristics can be realized as intended by the designer, such as extraction with a desired light distribution. Further, by adjusting the column diameter, light having a desired wavelength can be generated, and light of a desired mixed color, for example, white light can be generated. Furthermore, a phosphor that performs wavelength conversion may be mixed into the organic metal. Thus, a light-emitting diode adapted to white light can be realized, and the light-emitting diode is extremely suitable for a lighting device in combination with the excellent light extraction efficiency and light distribution as described above.

  In growing the nanocolumn 6, the compound semiconductor material such as Ga, N, In, and Al and the additive material such as Mg, Si, and Zn are dissolved and taken in, and is a synthetic product. The substrate is formed of a catalyst material layer such as Ni, Cu, Fe, Au, etc. that does not form a crystal, and a compound seed crystal layer, such as AlN, that grows in the columnar crystal structure by adsorbing and bonding the compound semiconductor material and additive material Alternatively, the nanocolumn can be grown in a short time by forming it in advance on the buffer layer.

  Further, since the nanocolumn 6 is sealed with the p-type layer 7, the nanocolumn 6 is separated from the sapphire substrate 1 using the laser lift-off method using the sapphire substrate 1 advantageous for crystal growth, and an n-type electrode is separately attached. Thus, a current may be supplied in the thickness direction of the substrate.

[Embodiment 2]
FIG. 2 is a cross-sectional view schematically showing a manufacturing process of a light-emitting diode that is a compound semiconductor device according to a second embodiment of the present invention. This light-emitting diode is similar to the above-described light-emitting diode, and corresponding portions are denoted by the same reference numerals and description thereof is omitted. It should be noted that in the present embodiment, the Si substrate 11 which is a conductive substrate is used as the substrate. First, as shown in FIG. 2A, a low-temperature GaN amorphous layer 12 is deposited by 2 μm on the Si substrate 11 by MOCVD, and a high-temperature GaN single crystal layer 13 is further deposited thereon by several hundred nm. The GaN amorphous layer 12 and the GaN single crystal layer 13 serve as a buffer layer for growth of a GaN: Si nanocolumn 15 described later.

Next, similarly to FIG. 1, the SiO ₂ thin film 4 which is an insulating film is deposited by 50 μm by EB deposition, and the opening 5 is formed by using a normal lithography technique and an etching technique. Thereafter, the temperature is again set in the MOCVD apparatus and the temperature is set to 900 ° C., and silane (SiH ₄ ) is supplied in order to dope the TMG, NH _3, and Si serving as an n-type impurity material, thereby FIG. ): GaN: Si nanocolumns 15 are grown to 100 nm. Here, the energy band gap of the GaN: Si nanocolumn 15 is 3.4 eV.

It should also be noted that in the present embodiment, trimethyl trimethyl trioxide is used for In doping instead of the silane (SiH ₄ ) using the GaN: Si nanocolumn 15 as a core layer and using the MOCVD apparatus around it. By supplying indium (In (CH ₃ ) ₃ ), as shown in FIG. 2C, the InGaN layer 16 is grown in a shell shape. The thickness of this InGaN layer 16 is about 3 nm. Thereafter, an Si-doped n-type GaN layer 17 is again grown in a shell shape with a thickness of 5 nm on the outside of the InGaN layer 16, and this is used as a cap layer. This cap layer serves as an electron barrier layer and serves to prevent In diffusion from the InGaN layer 16 to the p-type layer 7. Multiple quantum wells can be formed by forming the InGaN layer 16 and the n-type GaN layer 17 in multiple layers.

  Next, as in FIG. 1, the aqueous solution containing the organometallic PEDOT: PSS is spin-coated, deposited to a thickness of about 100 nm, baked to remove moisture, and the p is removed as shown in FIG. A mold layer 7 is formed. Subsequently, similarly to FIG. 1, a Ni 5 nm / ITO 25 nm laminated film, which is a transparent conductive layer, is formed by sputtering deposition to form a p-type transparent electrode 8, and a Ni 30 nm / Au 500 nm laminated film is deposited on the p-type transparent electrode 8. Then, the p-type electrode pad 9 is partially formed by normal lithography and etching. Thereafter, in the present embodiment, Ti 30 nm / Au 500 nm is evaporated on the back surface of the Si substrate 11 to form the n-type electrode 18. Since the Si substrate 11 can be made sufficiently conductive in advance by P doping, the n-type electrode 18 on the back surface is electrically connected to the GaN: Si nanocolumn 15 of the core layer. Can do.

In the light-emitting diode manufactured as described above, the GaN: Si nanocolumn 15 grows in close contact with the opening 5 of the SiO ₂ thin film 4, so that the GaN single crystal layer 13 connected to the n-type electrode 18. And the p-type layer 7 connected to the p-type transparent electrode 8 are electrically insulated. Here, the InGaN layer 16 has an energy band gap of 2.6 eV and an emission wavelength of about 460 nm. As described above, the energy band gap of PEDOT: PSS is 3 eV. Accordingly, the p-type layer 7 is transparent with respect to the emission wavelength from the InGaN layer 16, and the InGaN layer 16 serves as a well layer for carrier recombination emission due to the difference in energy band gap.

  Even in such a configuration, even if the organic metal is insufficiently filled by the spin coating or the like, leakage or short-circuit can be prevented, and reliability can be improved. The p-type transparent electrode 8 can be easily formed on the p-type layer 7 which is a sealing member. Furthermore, by using a conductive substrate, the series resistance can be reduced, and a nanocolumn LED with higher current and higher output can be realized.

  Here, the GaN: Si nanocolumn 15 serving as the n-type core layer has a function of a quantum well for accumulating electrons and holes. By storing the electrons and holes in this quantum well, The probability of coupling is increased, and a high-efficiency light-emitting device can be realized. Further, by changing the band gap width of the n-type core layer, light having a desired wavelength can be extracted. Regarding the magnitude relationship of the band gap between the n-type core layer and the InGaN layer 16 serving as the n-type shell layer, it cannot be said that either one is generally good, and the n-type core layer band gap width Eg (core) <n-type shell layer band. The gap width Eg (shell) has the advantage of excellent carrier confinement and improved light emission recombination efficiency, but also has the disadvantage of becoming a barrier for hole conduction and increasing the series parasitic resistance. In any case, a nanocolumn having higher emission efficiency than a nanocolumn LED having only an n-type core layer is obtained by using different Eg (core) and Eg (shell) sizes and optimizing the trade-off. An LED can be realized.

Preferably, since a light-shielding Si substrate 11 is used, a reflective film that can withstand high temperatures during nanocolumn growth by MOCVD, such as rhodium, is formed on the SiO ₂ thin film 4 so that the InGaN layer 16 It is possible to prevent the light emitted to the side from being absorbed by the Si substrate 11. In the rhodium reflective film, an opening 5 can be formed by dry etching together with the underlying SiO ₂ thin film 4.

  Note that although the tip of the GaN: Si nanocolumn 15 is in direct contact with the p-type layer 7, light emission slightly occurs at this portion at the pn junction, and a large short-circuit current does not flow.

[Embodiment 3]
FIG. 3 is a cross-sectional view schematically showing a manufacturing process of a light-emitting diode which is a compound semiconductor element according to the third embodiment of the present invention. This light-emitting diode is similar to the light-emitting diode shown in FIG. 2 described above, and corresponding portions are denoted by the same reference numerals, and description thereof is omitted. It should be noted that in this embodiment, as shown in FIG. 3A, the GaN amorphous layer 12 and the GaN single crystal layer 13 are formed on the Si substrate 21 which is a conductive substrate, as shown in FIG. After forming the SiO ₂ thin film 4 and the opening 5, in a MOCVD apparatus, the temperature is set to 900 ° C., and in order to dope Mg as a p-type impurity material together with the TMG and NH ₃ , It is to supply enilmagnesium (Cp ₂ Mg). Thereby, as shown in FIG. 3B, a GaN: Mg nanocolumn 25 is grown to 100 nm. Here, the energy band gap of the GaN: Mg nanocolumn 25 is also 3.4 eV.

Then, using the GaN: Mg nanocolumn 25 as a core layer and using the same MOCVD apparatus, trimethylindium (In (CH) is used for In doping instead of the cyclopentadienyl magnesium (Cp ₂ Mg). ₃ ) By supplying ₃ ), the InGaN layer 16 is grown in a shell shape as shown in FIG. The thickness of this InGaN layer 16 is about 3 nm. Thereafter, an Mg-doped p-type GaN layer 26 is grown again in a shell shape with a thickness of 5 nm on the outside of the InGaN layer 16, and this is used as a cap layer. The cap layer serves as an electron barrier layer and serves to prevent diffusion of In from the InGaN layer 16 to the n-type layer 27 described later. It is also possible to form a multiple quantum well by forming the InGaN layer 16 and the p-type GaN layer 26 in multiple layers.

Subsequently, it should be noted that the sample is set in an MBE apparatus corresponding to the p-type core layer, and the organic substance Alq ₃ (Tris (8-hydroxyquinoline) doped with Al) is vacuumed (10 ⁻⁶ ). In Torr), Alq ₃ having a thickness of about 100 nm is deposited on the sample by heating and evaporation at a K cell temperature of 350 ° C. for 100 minutes. This organic substance Alq ₃ is an organic metal having a property of conducting only electrons, and forms the n-type layer 27 of the nanocolumn LED. Alq _{3 has} an energy band gap of 2.5 to 2.7 eV and is transparent to the emission wavelength from the InGaN layer 16. Due to the difference in energy band gap, the InGaN layer 16 serves as a well layer for carrier recombination light emission. The organics to such an electronic only conducted, other has anthracene, the energy band gap is 3.9 e V, which is transparent over a wider wavelength region.

  Thereafter, an ITO film, which is a transparent conductive layer, is formed by sputtering deposition to a thickness of 25 nm to form an n-type transparent electrode 28, and a Ti 30 nm / Au 500 nm laminated film is deposited as a bonding pad on the n-type transparent electrode 28. As a result, an n-type electrode pad 29 is partially formed. Further, Ti 30 nm / Au 500 nm is deposited on the back surface of the Si substrate 21 to form the p-type electrode 30. Since the Si substrate 21 can be made sufficiently conductive in advance by B doping, the p-type electrode 30 on the back surface is electrically connected to the GaN: Mg nanocolumn 25 of the core layer. Can do.

  In this way, a nanocolumn LED using a p-type core layer and a p-type shell layer can be produced. When the p-type core layer and the p-type shell layer are used, the majority carrier of the quantum well becomes a hole, and the problem that the hole is normally limited by supply of light by recombination of light emission can be solved. A nanocolumn LED can be realized.

It is sectional drawing which shows typically the manufacturing process of the light emitting diode which is a compound semiconductor element which concerns on the 1st Embodiment of this invention. It is sectional drawing which shows typically the manufacturing process of the light emitting diode which is a compound semiconductor element which concerns on the 2nd Embodiment of this invention. It is sectional drawing which shows typically the manufacturing process of the light emitting diode which is a compound semiconductor element which concerns on the 3rd Embodiment of this invention.

1 sapphire substrate 2 n-type GaN layer 4 SiO ₂ thin film 5 opening 6 GaN: Zn nanocolumn 7 p-type layer 8 p-type transparent electrode 9 p-type electrode pads 10 and 18 n-type electrodes 11 and 21 Si substrate 12 GaN amorphous layer 13 GaN single crystal layer 15 GaN: Si nanocolumn 16 InGaN layer 17 n-type GaN layer 25 GaN: Mg nanocolumn 26 p-type GaN layer 27 n-type layer 28 n-type transparent electrode 29 n-type electrode pad 30 p-type electrode

Claims (4)

In a compound semiconductor device having a plurality of nanoscale columnar crystal structures on a substrate or a buffer layer,
An insulating film formed on the substrate or buffer layer connected to the electrode of the first conductivity type and having an opening for the growth of the columnar crystal structure;
It is made of an organic metal having translucency and having a second conductivity type opposite to the first conductivity type, and is connected to an electrode of the second conductivity type to seal the columnar crystal structure. look including a sealing member,
The columnar crystal structure is formed in a coaxial shape having a core portion showing the first conductivity type and a shell portion surrounding the core portion and showing the first conductivity type, and the band gap energy A compound semiconductor device having different sizes .   A catalyst material layer which dissolves and takes in compound semiconductor material and additive material and does not form a composite with itself between the substrate or buffer layer and the insulating film, or the compound semiconductor material and 2. The compound semiconductor device according to claim 1, further comprising a compound seed crystal layer that grows into the columnar crystal structure by adsorbing and bonding an additive material.   An illumination device using the compound semiconductor element according to claim 1. In a method for producing a compound semiconductor device having a plurality of nanoscale columnar crystal structures on a substrate or a buffer layer,
An insulating film is formed on the substrate or buffer layer to be connected to the electrode of the first conductivity type, and corresponds to a column diameter to be grown at an arrangement position where the columnar crystal structure is to be grown. Patterning the insulating film into a shape and forming an opening so that the substrate or buffer layer is exposed;
Crystal growth of the columnar crystal structure with the first conductivity type from the substrate or buffer layer exposed in the opening;
The columnar sealing member is made of an organic metal having translucency and having a second conductivity type opposite to the first conductivity type, and is connected to an electrode of the second conductivity type. look including a step of sealing the crystal structure,
The step of crystal-growing the columnar crystal structure has a step of growing a core portion showing the first conductivity type and a band gap energy having a magnitude different from that of the core portion, and surrounds the core portion. And a step of growing a shell portion having the first conductivity type in a coaxial shape .

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