JP6920630B2 - Ultraviolet light emitting material and its manufacturing method - Google Patents

Description

The present invention relates to a novel and useful ultraviolet light emitting material and a method for producing the same.

In recent years, ultraviolet-emitting phosphors that emit ultraviolet rays have been developed. Ultraviolet rays are classified into near ultraviolet rays (wavelength 200-380 nm), far ultraviolet rays (wavelength 10-200 nm), and extreme ultraviolet rays (wavelength 10 nm or less) according to the wavelength. Near ultraviolet rays are further divided into UV-A (wavelength 315-380 nm), UV-B (wavelength 280-315 nm), and UV-C (wavelength 200-280 nm). These ultraviolet rays are selected and used according to the application such as insect repellent, sterilization, deodorization, stain prevention, exposure and skin treatment.

Patent Document 1 describes a method for producing a thin film of an ultraviolet light emitting material by heat-treating zinc oxide and gallium oxide and / or phosphorus oxide in a non-oxidizing atmosphere. However, such an ultraviolet light emitting material requires a plurality of heat treatments, and the process is complicated, so that there is a problem that it takes time and cost to manufacture. In addition, it is difficult to control the uniformity in the film, cracks and the like are likely to occur, and there is a problem that the quality of the film should be solved.

Further, in relation to the present invention, Non-Patent Document 1 discloses the CL spectrum of _{β-Ga 2} O _3.

Japanese Unexamined Patent Publication No. 2013-095838

T. Onuma et al., “Correlation between blue luminescence intensity and resistivity in β-Ga2O3 single crystals”, APPLIED PHYSICS LETTERS 103, 041910 (2013)

An object of the present invention is to provide an ultraviolet light emitting material capable of emitting ultraviolet rays having a shorter wavelength and having excellent ultraviolet light extraction properties, and a method for producing the same.

As a result of diligent studies to achieve the above object, the present inventors surprisingly, the ultraviolet light emitting material having a corundum structure is shorter than the ultraviolet light emitting material having a β-gallia structure. We have found that ultraviolet rays of a wavelength can emit light and that the ultraviolet light can be taken out easily, and that such an ultraviolet light emitting material can solve the above-mentioned conventional problems at once.
In addition, after obtaining the above findings, the present inventors have further studied and completed the present invention.

That is, the present invention relates to the following invention.
[1] An ultraviolet light emitting material containing a crystalline oxide semiconductor containing at least one or more selected from aluminum, gallium and indium as a main component, and the crystalline oxide semiconductor having a corundum structure. ..
[2] The ultraviolet light emitting material according to the above [1], wherein the crystalline oxide semiconductor contains at least gallium.
[3] The mist or droplet generated by atomizing or dropletizing the raw material solution of the crystalline oxide semiconductor is conveyed to the substrate by a carrier gas, and then the mist or droplet is transferred onto the substrate. The ultraviolet light emitting material according to the above [1] or [2], which is obtained by thermally reacting the above-mentioned [1] or [2].
[4] The substrate is a crystal substrate, and a concavo-convex portion composed of concave or convex portions is formed on the crystal growth surface of the crystal substrate, directly or via another layer, and the mist or the mist or the above is formed on the concavo-convex portion. The ultraviolet light emitting material according to the above [3], wherein the droplets are thermally reacted by heating.
[5] The ultraviolet light emitting material according to the above [4], wherein a plurality of the uneven portions are formed periodically.
[6] The ultraviolet light emitting material according to the above [4] or [5], wherein the uneven portion is formed by forming a concave portion or a convex portion in a stripe shape or a dot shape.
[7] The ultraviolet light emitting material according to any one of the above [3] to [6], wherein the substrate is a sapphire substrate.
[8] An ultraviolet light emitting element containing an ultraviolet light emitting material that emits ultraviolet rays, wherein the ultraviolet light emitting material includes the ultraviolet light emitting material according to any one of the above [1] to [7].
[9] In the method for producing an ultraviolet light emitting material from a raw material solution, mist or droplets produced by atomizing or dropletizing a raw material solution containing at least one or more selected from aluminum, gallium and indium. A method for producing an ultraviolet light emitting material, which comprises transporting the mist or the droplets to a substrate with a carrier gas, and then causing the mist or the droplets to be thermally reacted by heating on the substrate.
[10] The production method according to the above [9], wherein the raw material solution contains at least gallium.
[11] The substrate is a crystal substrate, and a concavo-convex portion composed of concave or convex portions is formed on the crystal growth surface of the crystal substrate, directly or via another layer, and the mist or the mist or the above is formed on the concavo-convex portion. The production method according to the above [9] or [10], wherein the droplets are thermally reacted by heating.
[12] The manufacturing method according to the above [11], wherein a plurality of the uneven portions are formed periodically.
[13] The manufacturing method according to the above [11] or [12], wherein the uneven portion is formed by forming a concave portion or a convex portion in a stripe shape or a dot shape.
[14] The production method according to any one of the above [9] to [13], wherein the substrate is a sapphire substrate.

According to the production method of the present invention, it is possible to provide an ultraviolet light emitting material capable of emitting ultraviolet rays having a shorter wavelength and further having excellent ultraviolet light extraction properties, and a method for producing the same.

It is a schematic diagram which shows one aspect of the concavo-convex portion formed on the crystal growth surface of the crystal substrate used in this invention. It is a schematic diagram which shows one aspect of the concavo-convex portion formed on the crystal growth surface of the crystal substrate used in this invention. It is a schematic diagram which shows one aspect of the concavo-convex portion formed on the crystal growth surface of the crystal substrate used in this invention. It is a schematic diagram which shows one aspect of the concavo-convex portion formed on the crystal growth surface of the crystal substrate used in this invention. It is a schematic diagram which shows one aspect of the concavo-convex portion formed on the crystal growth surface of the crystal substrate used in this invention. It is a schematic diagram which shows one aspect of the concavo-convex portion formed on the crystal growth surface of the crystal substrate used in this invention. It is a figure which shows typically the cross section of the crystalline laminated structure of this invention. It is a figure which shows typically the cross section of the crystalline laminated structure (with a buffer layer) of this invention. It is a figure explaining the mist CVD apparatus used in an Example. It is a figure which shows the cathode luminescence spectroscopic measurement result in an Example. The result (half width distribution) of Raman spectroscopic analysis in the example is shown.

The ultraviolet light emitting material of the present invention is characterized by containing, as a main component, a crystalline oxide semiconductor containing at least one or more selected from aluminum, gallium and indium, and the crystalline oxide semiconductor has a corundum structure. And.

The oxide semiconductor is not particularly limited as long as it has a corundum structure and contains at least one or more of aluminum, gallium and indium. Examples of the oxide semiconductor include α-Ga ₂ O ₃ , α- (Al _x Ga _1-x ) ₂ O ₃ (however, 1>X> 0), α- (In _Y Ga _1-Y ) _2. Examples thereof include O ₃ (however, 1>Y> 0), α- (Al _Z1 Ga _Z2 In _Z3 ) ₂ O ₃ (however, 1> Z1, Z2, Z3> 0 and Z1 + Z2 + Z3 = 1). In the present invention, it is more preferable that the oxide semiconductor contains at least gallium.

The "main component" includes, for example, when the oxide semiconductor is α-Ga ₂ O _{3 , α-Ga 2} O ₃ is contained at a ratio of gallium in the metal element of the film of 0.5 or more. If so, that's fine. In the present invention, the atomic ratio of gallium in the metal element in the thin film is preferably 0.7 or more, more preferably 0.8 or more. The shape of the oxide semiconductor is not particularly limited, but it is preferably film-like or plate-like, and more preferably film-like. The film thickness in the form of a film is not particularly limited and may be 1 μm or less or 1 μm or more, but in the present invention, it is preferably 1 μm or more, and is 3 μm or more. Is more preferable. The oxide semiconductor is usually a single crystal, but may be a polycrystal.

The method for producing the ultraviolet light emitting material is not particularly limited, but the mist or droplets produced by atomizing or dropletizing the raw material solution is conveyed to the substrate with a carrier gas, and then the mist or droplets are carried on the substrate. A method in which the droplets are thermally reacted by heating is preferable.

(Raw material solution)
The raw material solution is not particularly limited and is usually appropriately selected depending on the ultraviolet light emitting material. For example, an aqueous solution or a solution of a gallium compound and, if desired, a metal compound such as an indium compound or an aluminum compound and the like. Can be mentioned. As the gallium compound, a gallium metal may be used as a starting material and changed to a gallium compound immediately before film formation. Examples of the gallium compound include an organic metal complex of gallium (eg, an acetylacetonate complex) and a halide (fluoride, chloride, bromide, or iodide). In the present invention, the halide (fluoride) is used. , Chloride, bromide, or iodide).

In addition, the raw material solution may contain a dopant. The dopant is not particularly limited and may be a known one. Examples of the dopant include n-type dopants such as tin, germanium, silicon, titanium, zirconium, vanadium and niobium, and p-type dopants. In the present invention, the dopant is preferably Ge or Si. The content of Ge or Si is preferably 0.00001 atomic% or more, more preferably 0.00001 atomic% to 20 atomic%, and 0.00001 atomic% in the composition of the ultraviolet light emitting material. Most preferably, it is 10 atomic%.

<Hpokeimenon>
The substrate is not particularly limited as long as it can support the film. The material of the substrate is not particularly limited as long as it does not impair the object of the present invention, and may be a known substrate, an organic compound, or an inorganic compound. The shape of the substrate may be any shape and is effective for any shape, for example, plate-like, fibrous, rod-like, columnar, prismatic, such as a flat plate or a disk. Cylindrical, spiral, spherical, ring-shaped and the like can be mentioned, but in the present invention, a substrate is preferable. The thickness of the substrate is not particularly limited in the present invention.

The crystal substrate is not particularly limited as long as it is a substrate containing a crystal as a main component, and may be a known substrate. It may be an insulator substrate, a conductive substrate, or a semiconductor substrate. It may be a single crystal substrate or a polycrystalline substrate. Examples of the crystal substrate include a substrate containing a crystal having a corundum structure as a main component, a substrate containing a crystal having a β-gaul structure as a main component, and a substrate having a hexagonal structure. The "main component" refers to a composition ratio in the substrate containing 50% or more of the crystals, preferably 70% or more, and more preferably 90% or more.

Examples of the substrate containing the crystal having a corundum structure as a main component include a sapphire substrate and an α-type gallium oxide substrate. Examples of the substrate containing the crystal having a β-gaul structure as a main component include a β-Ga ₂ O ₃ substrate or a mixed crystal substrate containing β-Ga ₂ O ₃ and Al ₂ O _3. .. As the mixed crystal substrate containing β-Ga ₂ O ₃ and Al ₂ O ₃ , for example, a mixed crystal substrate in which Al ₂ O ₃ is more than 0 wt% and 60 wt% or less can be mentioned as a preferable example. .. Examples of the substrate having the hexagonal structure include a SiC substrate, a ZnO substrate, and a GaN substrate. Examples of other crystal substrates include Si substrates.

In the present invention, the crystal substrate is preferably a sapphire substrate. Examples of the sapphire substrate include a c-plane sapphire substrate, an m-plane sapphire substrate, and an a-plane sapphire substrate. Further, the sapphire substrate may have an off angle. The off angle is not particularly limited, but is preferably 0 ° to 15 °.
The thickness of the crystal substrate is not particularly limited, but is preferably 50 to 2000 μm, and more preferably 200 to 800 μm.

Further, in the present invention, the substrate is preferably a crystal substrate, and a concavo-convex portion composed of a concave portion or a convex portion is formed on the crystal growth surface of the crystal substrate directly or via another layer, and the concavo-convex portion is formed. It is more preferable that the mist or the droplets are thermally reacted by heating on the part.

<Uneven part>
The concavo-convex portion is not particularly limited as long as it is composed of a convex portion or a concave portion, and may be a concavo-convex portion composed of a convex portion, a concavo-convex portion composed of a concave portion, or from the convex portion and the concave portion. It may be an uneven portion. Further, the uneven portion may be formed from a regular convex portion or a concave portion, or may be formed from an irregular convex portion or a concave portion. In the present invention, it is preferable that the uneven portion is formed periodically, and it is more preferable that the uneven portion is periodically and regularly patterned. The shape of the uneven portion is not particularly limited, and examples thereof include a striped shape, a dot shape, a mesh shape, and a random shape. In the present invention, the striped shape or the dot shape is preferable. When forming the uneven portion in a dot shape, for example, a triangle, a quadrangle (for example, a square, a rectangle, or a trapezoid) is periodically and regularly arranged at a grid position such as a square grid, an oblique grid, a triangular grid, or a hexagonal grid. Etc.), polygonal shapes such as pentagons and hexagons, and concavo-convex portions such as circular and elliptical shapes can be arranged. The cross-sectional shape of the concave or convex portion of the uneven portion is not particularly limited, and is, for example, U-shaped, U-shaped, inverted U-shaped, corrugated, or triangular, quadrangular (for example, square, rectangular, trapezoidal, etc.). ), Polygons such as pentagons and hexagons, etc.

The constituent material of the convex portion is not particularly limited and may be a known material. It may be an insulator material, a conductor material, or a semiconductor material, but a material capable of inhibiting crystal growth in the longitudinal direction is preferable. Further, the constituent material may be amorphous, single crystal, or polycrystalline. Examples of the constituent material of the convex portion include oxides such as Si, Ge, Ti, Zr, Hf, Ta, Sn, nitrides or carbides, carbines, diamonds, metals, and mixtures thereof. More specifically, _{a Si-containing compound containing SiO 2} , SiN or polycrystalline silicon as a main component, and a metal having a melting point higher than the crystal growth temperature of the crystalline semiconductor (for example, platinum, gold, silver, palladium, rhodium). , Iridium, precious metals such as ruthenium, etc.). The content of the constituent material is preferably 50% or more, more preferably 70% or more, and most preferably 90% or more in the convex portion in terms of composition ratio.

The means for forming the convex portion may be a known means, for example, a known patterning processing means such as photolithography, electron beam lithography, laser patterning, and subsequent etching (for example, dry etching or wet etching). Can be mentioned. In the present invention, the convex portion is preferably striped or dot-shaped, and more preferably striped.

The concave portion is not particularly limited, but may be the same as the constituent material of the convex portion, or may be a crystal substrate. In the present invention, the recesses are preferably dot-shaped, and it is more preferable that the mask layer made of the silicon-containing compound is provided with dot-shaped recesses. As the means for forming the concave portion, the same means as the means for forming the convex portion can be used. It is also preferable that the recess is a void layer provided on the crystal growth surface of the crystal substrate. The void layer can be formed on the crystal growth surface of the crystal substrate by providing a groove in the crystal substrate by a known groove processing means. The groove width, groove depth, terrace width, etc. of the void layer are not particularly limited and can be appropriately set as long as the object of the present invention is not impaired. Further, the void layer may contain air, or may contain an inert gas or the like.

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows one aspect of the uneven portion provided on the crystal growth surface of the crystal substrate in the present invention. The uneven portion of FIG. 1 is formed of a crystal substrate 1 and a convex portion 2a on the crystal growth surface 1a. The convex portion 2a has a striped shape, and the striped convex portion 2a is periodically arranged on the crystal growth surface 1a of the crystal substrate 1. The convex portion 2a is made _{of a silicon-containing compound such as SiO 2} , and can be formed by using a known means such as photolithography.

FIG. 2 shows one aspect of the uneven portion provided on the crystal growth surface of the crystal substrate in the present invention, and shows another aspect from FIG. Similar to FIG. 1, the uneven portion of FIG. 2 is formed of a crystal substrate 1 and a convex portion 2a provided on the crystal growth surface 1a. The convex portions 2a are dot-shaped, and the dot-shaped convex portions 2a are periodically and regularly arranged on the crystal growth surface 1a of the crystal substrate 1. The convex portion 2a is made _{of a silicon-containing compound such as SiO 2} , and can be formed by using a known means such as photolithography.

FIG. 3 shows one aspect of the uneven portion provided on the crystal growth surface of the crystal substrate in the present invention. FIG. 3 has a concave portion 2b instead of a convex portion. The recess in FIG. 3 is formed of the crystal substrate 1 and the mask layer 4. The mask layer is formed on the crystal growth surface 1 and has holes in a dot shape. The crystal substrate 1 is exposed from the dot holes of the mask layer 4, and dot-shaped recesses 2b are formed on the crystal growth surface 1a. The recess 2b can be obtained by forming the mask layer 4 by using a known means such as photolithography. Further, the mask layer 4 is not particularly limited as long as it is a layer capable of inhibiting crystal growth in the vertical direction. Examples of the constituent material of the mask layer 4 include known materials such as silicon-containing compounds such as _{SiO 2.}

FIG. 4 shows an aspect of the uneven portion provided on the crystal growth surface of the crystal substrate in the present invention. The uneven portion of FIG. 4 is formed of the crystal substrate 1 and the void layer. The void layer has a striped shape, and striped recesses 2b are periodically arranged on the crystal growth surface 1a of the crystal substrate 1. The recess 2b can be formed by a known groove processing means.

Further, FIG. 5 also shows one aspect of the uneven portion provided on the crystal growth surface 1a of the crystal substrate 1 in the present invention. In the uneven portion of FIG. 5, the distance between the concave portions 2b is different from that of FIG. 4, and the width of the gap is small. That is, the terrace width of the recess 2b is wide in FIG. 4 and narrow in FIG. The recess 2b of FIG. 5 can also be formed by using a known grooving means, similarly to the recess of FIG.

FIG. 6 shows one aspect of the concavo-convex portion provided on the crystal growth surface of the crystal substrate in the present invention, as in FIGS. 4 and 5, and the concavo-convex portion of FIG. 6 is formed from the crystal substrate 1 and the void layer. Has been done. Unlike FIGS. 4 and 5, the void layer has a dot shape, and the dot-shaped recesses 2b are periodically and regularly arranged on the crystal growth surface 1a of the crystal substrate 1. The recess 2b can be formed by a known groove processing means.

The width and height of the convex portion of the uneven portion, the width and depth of the concave portion, the interval, and the like are not particularly limited, but in the present invention, each is in the range of, for example, about 10 nm to about 1 mm, preferably about 10 nm to about 10 nm. It is about 300 μm, more preferably about 10 nm to about 1 μm, and most preferably about 100 nm to about 1 μm.

Further, in the present invention, another layer such as a buffer layer or a stress relaxation layer may be provided on the crystal substrate, and when the other layer is provided, the uneven portion is provided on or under the other layer. However, usually, the uneven portion is formed on another layer.

(Production method)
In the present invention, preferably, the raw material solution is atomized or dropleted (atomization / droplet atomization step), and the generated mist or droplet is supplied to the substrate by a carrier gas (mist / droplet supply). Step), the supplied mist or droplets are thermally reacted by heating to form a film (deposition step).

In the atomization / droplet atomization step, the raw material solution is prepared, and the mixing ratio of the metal compound in the raw material solution that atomizes or dropletizes the raw material solution to generate mist is not particularly limited, but the entire raw material solution is used. On the other hand, 0.0001 mol / L to 20 mol / L is preferable. The atomizing or droplet forming means is not particularly limited as long as the raw material solution can be atomized or dropletized, and may be a known atomizing means or droplet forming means, but in the present invention, it is super It is preferably an atomizing means or a droplet forming means using sound waves. The mist or the droplet is preferably one that has an initial velocity of zero and floats in the air, and is more preferably a mist that floats in space and can be conveyed as a gas rather than being sprayed like a spray. preferable. The droplet size is not particularly limited and may be a droplet of about several mm, but is preferably 50 μm or less, and more preferably 1 to 10 μm.

In the mist / droplet supply step, the mist or droplets are supplied to the substrate by the carrier gas. The type of carrier gas is not particularly limited as long as the object of the present invention is not impaired, and for example, an inert gas such as oxygen, ozone, nitrogen or argon, or a reducing gas such as hydrogen gas or forming gas is a preferable example. Is listed as. Further, the type of the carrier gas may be one type, but may be two or more types, and a diluted gas having a changed carrier gas concentration (for example, a 10-fold diluted gas) or the like is used as the second carrier gas. It may be used further. Further, the carrier gas may be supplied not only at one location but also at two or more locations. The flow rate of the carrier gas is not particularly limited, but the linear velocity in the reactor (more specifically, the reactor is hot and changes depending on the environment, so room temperature is assumed. The converted linear velocity) is preferably 0.1 m / s to 100 m / s, more preferably 1 m / s to 10 m / s.

In the film forming step, the mist or the droplets are thermally reacted to form a film on a part or all of the surface of the substrate. The thermal reaction may be such that the mist or the droplets react with heat, the heating means may be a known means, and the reaction conditions and the like are not particularly limited as long as the object of the present invention is not impaired. In this step, the thermal reaction is usually carried out at a temperature equal to or higher than the evaporation temperature of the solvent, but is preferably not too high or lower. Further, the thermal reaction may be carried out in any of a vacuum, a non-oxygen atmosphere, a reducing gas atmosphere and an oxygen atmosphere as long as the object of the present invention is not impaired, and the thermal reaction may be carried out under atmospheric pressure or pressure. It may be carried out under either reduced pressure or reduced pressure, but in the present invention, it is preferable to carry out under atmospheric pressure because the calculation of the evaporation temperature becomes easy. In the case of vacuum, the evaporation temperature can be lowered. Further, the film thickness can be set by adjusting the film formation time.

The ultraviolet light emitting material is useful as an ultraviolet light source, and can be preferably used by using known means or the like.

Hereinafter, examples of the present invention will be described, but the present invention is not limited thereto.

1. 1. Mist CVD device First, the mist CVD device 19 used in this embodiment will be described with reference to FIG. The mist CVD apparatus 19 is for adjusting the flow rate of the sample table 21 on which the film-forming sample 20 such as the base substrate is placed, the carrier gas source 22 for supplying the carrier gas, and the carrier gas sent out from the carrier gas source 22. From the flow rate control valve 23, the mist generation source 24 in which the raw material solution 24a is housed, the container 25 in which the water 25a is placed, the ultrasonic transducer 26 attached to the bottom surface of the container 25, and a quartz tube having an inner diameter of 40 mm. The film forming chamber 27 and the heater 28 installed in the peripheral portion of the film forming chamber 27 are provided. The sample table 21 is made of quartz, and the surface on which the sample to be filmed 20 is placed is inclined from the horizontal plane. By making both the film forming chamber 27 and the sample table 21 out of quartz, it is possible to prevent impurities derived from the apparatus from being mixed into the thin film formed on the sample to be filmed 20.

2. Formation of uneven portion A c-plane sapphire substrate was used as the crystal substrate. _{SOG was applied with a spin coater and a stripe of SiO 2} (parallel to the m-axis) was formed on the c-plane sapphire substrate by a photolithography method.

3. 3. Preparation of Raw Material Solution An aqueous solution of gallium bromide 0.1 mol / L was prepared, and at this time, a 48% hydrobromic acid solution was further contained so as to have a volume ratio of 10%, and this was used as a raw material solution.

4. Preparation for film formation 3. The raw material solution 24a obtained in 1) was housed in the mist generation source 24. Next, as the sample 20 to be filmed, a square crystal growth substrate having a side of 10 mm is placed on the sample table 21, and the heater 28 is operated to raise the temperature in the film forming chamber 27 to 580 ° C. I let you. Next, the flow rate control valve 23 is opened to supply the carrier gas from the carrier gas source 22 into the film forming chamber 27, and after sufficiently replacing the atmosphere of the film forming chamber 27 with the carrier gas, the flow rate of the carrier gas is 5 L / L. It was adjusted to min. Oxygen was used as the carrier gas.

5. Single-layer film formation Next, the ultrasonic transducer 26 was vibrated at 2.4 MHz, and the vibration was propagated to the raw material solution 24a through water 25a to atomize the raw material solution 24a to generate raw material fine particles. The raw material fine particles were introduced into the film forming chamber 27 by the carrier gas and reacted in the film forming chamber 27 at 580 ° C. to form a thin film on the sample to be formed. The film formation time was 4 hours.

6. Evaluation Above 5. The phase of _{the α-Ga 2} O ₃ thin film obtained in the above was identified. Identification was performed by performing a 2θ / ω scan at an angle of 15 to 95 degrees using an XRD diffractometer for thin films. The measurement was performed using CuKα ray. As a result, it was _{α-Ga 2} O _3.

The obtained film was subjected to cross-sectional CL intensity mapping using a cathodoluminescence spectroscope. The results are shown in FIG. From FIG. 10, it can be seen that good luminescence is exhibited in the vicinity of 330 nm, the spectrum half width is also good, and the ultraviolet light extraction property is also excellent. In addition, Raman mapping measurement was performed using a laser Raman spectroscopic measuring device. The results are shown in FIG. From FIG. 11, it can be seen that the obtained film has good crystallinity.

The ultraviolet light emitting material of the present invention can be used in all fields such as electronic parts / electrical equipment parts, optical / electrophotographic related devices, and industrial parts, but is particularly useful for an ultraviolet light source.

1 Crystal substrate 1a Crystal growth surface 2a Convex part 2b Concave part 3 Epitaxial layer 4 Mask layer 5 Buffer layer 19 Mist CVD device 20 Film-deposited sample 21 Sample stand 22 Carrier gas source 23 Flow control valve 24 Mist generation source 24a Raw material solution 25 Container 25a Water 26 Ultrasonic transducer 27 Deposition chamber 28 Heater

Claims (5)

In a method for producing an ultraviolet emitting element by forming an ultraviolet emitting material, the formation of the ultraviolet emitting material includes at least one or more selected from aluminum, gallium and indium, and includes a raw material of the ultraviolet emitting material. The mist or droplet generated by atomizing or dropletizing the raw material solution is conveyed by a carrier gas to a substrate containing a crystal having a corundum structure as a main component , and then the mist or droplet is transferred onto the substrate. Is thermally reacted by heating to form a thin film containing an oxide semiconductor having a corundum structure having at least one or more selected from aluminum, gallium and indium as a main component. A method for manufacturing a light emitting element. The production method according to claim 1, wherein the raw material solution contains at least gallium. The substrate is a crystal substrate,
A claim in which a concavo-convex portion composed of a concave portion or a convex portion is formed on the crystal growth surface of the crystal substrate directly or via another layer, and the mist or the droplet is thermally reacted by heating on the concavo-convex portion. Item 2. The manufacturing method according to Item 1 or 2. The manufacturing method according to claim 3, wherein a plurality of the uneven portions are formed periodically. The manufacturing method according to claim 3 or 4 , wherein the uneven portion is formed by forming a concave portion or a convex portion in a striped shape or a dot shape.

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