JP5565793B2 - Deep ultraviolet light emitting device and manufacturing method thereof - Google Patents

Description

  The present invention relates to a deep ultraviolet light-emitting device and a method for manufacturing the same, and more particularly to a deep ultraviolet light-emitting device having high luminous efficiency, suitable for increasing the area, and easily manufactured, and a method for manufacturing the same.

  Deep ultraviolet light sources are used in various fields such as lighting, sterilization, medical treatment, water purification, and measurement. The deep ultraviolet light mainly refers to a wavelength of about 200 to about 350 nm, and in some cases includes a wavelength of 100 nm or more and 200 nm or less (hereinafter also referred to as DUV (Deep Ultraviolet) light). As means for generating deep ultraviolet light, mercury lamps, semiconductor light emitting devices (semiconductor LEDs), excimer lamps, and the like are known.

  In a mercury lamp, arc discharge is caused in mercury vapor in a glass tube, and ultraviolet light having a specific wavelength (for example, 254 nm) is generated. In an excimer lamp, a discharge gas (rare gas or rare gas halogen compound) is filled in a double quartz tube, and a high frequency / high voltage is applied between the electrodes through the quartz tube, thereby exciting the discharge gas to ultraviolet light. Generate light.

  On the other hand, nitride-based deep ultraviolet light-emitting elements are known as semiconductor LEDs (see Patent Document 1 below). In the lateral structure element disclosed in Patent Document 1, since the current must flow in the n-type AlGaN layer in the lateral direction, the element resistance is increased, the amount of heat generation is increased, and the carrier injection efficiency is adversely affected. There are disadvantages that arise. Therefore, it is not suitable for high output operation. Further, the chip size cannot be increased.

  As a device for improving this defect, a nitride-based deep ultraviolet light emitting device having a vertical structure is known (see Patent Documents 2 and 3 below). With the vertical structure disclosed in Patent Documents 2 and 3, the element resistance can be reduced, so that driving efficiency can be increased, heat generation can be suppressed, and high output operation is possible.

JP-A-11-307811 JP 2006-278554 A JP-T-2006-104063

  Among conventional deep ultraviolet light generating means, mercury lamps have a problem of using mercury which is bad for the environment. Further, the mercury lamp has a limited wavelength that can be generated, has a short lifetime, requires a high voltage, and is difficult to use.

  Excimer lamps have a problem that they are limited to special applications because they have a short lamp life and become large-sized devices.

  Nitride-based deep ultraviolet light-emitting elements are small in size and are expected to replace mercury lamps, but the nitride-based deep ultraviolet light-emitting elements disclosed in Patent Document 1 have low luminous efficiency and are compatible with high output. There is a problem that cannot be done. The nitride-based deep ultraviolet light emitting elements disclosed in Patent Documents 2 and 3 can be reduced in size, but in the deep ultraviolet region, the light emission efficiency is low and it is difficult to increase the output. That is, a multilayer structure is necessary, doping is necessary, and the level is deep, so that the carrier concentration cannot be increased. In particular, it is difficult to reduce the contact resistance of the electrode when the wavelength is shortened. For these reasons, it is difficult to increase the external quantum efficiency, and the manufacturing process is complicated.

  Accordingly, an object of the present invention is to provide a deep ultraviolet light-emitting device that solves the above-described problems, has high luminous efficiency, and is easy to manufacture, and a method for manufacturing the same.

  The object of the present invention is achieved by the following means.

  That is, the first deep ultraviolet light emitting device of the present invention includes an upper substrate, a lower substrate, a plurality of electrodes formed on one surface of the lower substrate, and a light emission formed on one surface of the upper substrate. A layer and a gas filled in a space formed by arranging the upper substrate and the lower substrate so that the electrode and the light emitting layer are opposed to each other, and a voltage is applied between the electrodes In addition, the light emitting layer emits deep ultraviolet light by plasma generated by the gas.

  The second deep ultraviolet light-emitting element of the present invention further includes a dielectric layer formed on the one surface of the lower substrate so as to cover the electrode in the first deep ultraviolet light-emitting element. The voltage applied between the two is an AC voltage.

  Further, the third deep ultraviolet light emitting device of the present invention is the above second deep ultraviolet light emitting device, wherein at least selected from the group consisting of MgO, AlN, AlGaN and AlGaInN on the dielectric layer. It is characterized by comprising a protective layer made of one material or the doped protective layer.

  The fourth deep ultraviolet light emitting element of the present invention is the above first deep ultraviolet light emitting element, wherein the electrode is exposed to the gas, and the voltage applied between the electrodes is a DC voltage. It is a feature.

  The fifth deep ultraviolet light emitting element of the present invention is generated corresponding to each of the electrodes forming a pair to which the voltage is applied in any one of the first to fourth deep ultraviolet light emitting elements. The plasma display device further includes a partition wall for separating the plasma from each other.

  The sixth deep ultraviolet light emitting device of the present invention is the above first to fifth deep ultraviolet light emitting device, wherein the upper substrate is formed of sapphire, and the light emitting layer is doped with AlGaN. It is characterized by being formed of AlGaN, diamond capable of emitting deep ultraviolet light, SiC, ZnO, ZnMnO, or boron nitride.

  The seventh deep ultraviolet light emitting device of the present invention is characterized in that, in the sixth deep ultraviolet light emitting device, the light emitting layer is formed of a superlattice AlGaN.

  Further, an eighth deep ultraviolet light emitting element of the present invention is the above sixth or seventh deep ultraviolet light emitting element, wherein the light emitting layer is AlGaN, and the ratio of Al in the light emitting layer is the light emitting layer. Or the vertical direction of the plane of the light emitting layer.

  The ninth deep ultraviolet light-emitting element of the present invention is the above-described first to eighth deep ultraviolet light-emitting element, wherein the gap between the light-emitting layer and the electrode is a pair to which the voltage is applied. It is characterized by being narrower than the interval between the electrodes.

The tenth deep ultraviolet light-emitting element of the present invention is the above-described first to ninth deep ultraviolet light-emitting element, wherein the gas is composed of Xe, Ne, He, Ar, N ₂ and H _2. It is at least one kind of gas selected from the group or a mixed gas thereof.

  The eleventh deep ultraviolet light-emitting element of the present invention is the auxiliary electrode according to any one of the first to tenth deep ultraviolet light-emitting elements, comprising a micro auxiliary electrode on the surface of the light emitting layer on the space side. The positive ion component in the plasma generated in the space is moved away from the light emitting layer by applying a positive voltage to and attracting electrons in the plasma generated in the space.

  Further, a twelfth deep ultraviolet light emitting element of the present invention is any one of the first to eleventh deep ultraviolet light emitting elements, wherein the distance between the adjacent electrodes, the distance between the electrodes and the light emitting layer, The width or the height of the electrode is 300 μm or less, or 300 μm to 1 mm.

  In addition, in a thirteenth deep ultraviolet light-emitting element according to the present invention, in the twelfth deep ultraviolet light-emitting element, at least one of an interval between the adjacent electrodes and an interval between the electrode and the light-emitting layer is 1 μm or less. It is characterized by that.

  The fourteenth deep ultraviolet light-emitting device of the present invention is the above-described third deep ultraviolet light-emitting device, wherein at least one of the dielectric layer and the protective layer is formed of a material having the same composition as the light-emitting layer. It is characterized by being.

  The fifteenth deep ultraviolet light emitting element of the present invention is the surface of the upper substrate on which the light emitting layer is formed, and the upper part of any one of the first to fourteenth deep ultraviolet light emitting elements. At least one of the surfaces of the substrate from which light is extracted, one surface of the lower substrate, or both of them are flat, convex, concave, surfaces having columnar portions, surfaces having wall-shaped portions, or It is characterized by a surface with a random height.

  In addition, the sixteenth deep ultraviolet light emitting element of the present invention is any one of the first to fifteenth deep ultraviolet light emitting elements, wherein the gas is sealed in the sealed space, or the space. It is characterized by having means for allowing the gas to flow in.

  In addition, the seventeenth deep ultraviolet light emitting device of the present invention is the metal or thermal conductivity for preventing temperature rise on the upper substrate or the lower substrate in any of the first to sixteenth deep ultraviolet light emitting devices. It is characterized by the fact that the materials are in close contact.

  The 18th deep ultraviolet light emitting element of the present invention is characterized in that, in the first deep ultraviolet light emitting element, the voltage is a voltage obtained by adding a direct current voltage and an alternating current voltage.

  In addition, the nineteenth deep ultraviolet light emitting device of the present invention is the light emitting layer of any one of the first to fifth deep ultraviolet light emitting devices, wherein the light emitting layer is formed of AlGaInN, and the deep ultraviolet light is 350 nm or less and 100 nm or more. It is characterized by being light having a wavelength within the range.

  Further, the twentieth deep ultraviolet light emitting element of the present invention is the electrode according to any one of the first to nineteenth deep ultraviolet light emitting elements, wherein means for generating a magnetic field in the space filled with the gas is provided. In the vicinity, the plasma is increased by the generated magnetic field.

  On the other hand, in the first method for manufacturing a deep ultraviolet light emitting device of the present invention, a first step of forming a light emitting layer on one surface of the upper substrate and a second step of forming a plurality of electrodes on one surface of the lower substrate. And a third step in which the electrode and the light emitting layer face each other, the upper substrate and the lower substrate are joined at a predetermined interval to form a space, and a fourth step in which a gas is sealed in the space. In addition, the light emitting layer is AlGaN, and the gas is a gas that generates plasma when a voltage is applied between the electrodes.

  The second deep ultraviolet light emitting device manufacturing method of the present invention is the above first deep ultraviolet light emitting device manufacturing method, wherein the first step is such that the proportion of Al in the light emitting layer is that of the light emitting layer. It is a step of forming the light emitting layer so as to change in a plane direction or a direction perpendicular to the plane of the light emitting layer.

According to the present invention, deep ultraviolet light can be generated with high efficiency. Conventionally, the external quantum efficiency of deep ultraviolet light with a wavelength of 200 nm is about 10 ⁻⁴ %. However, according to the present invention, an external quantum efficiency of 1% or more can be realized. Can be expected to improve to about 10%. The external quantum efficiency is a ratio (%) of light emission energy to input power energy. In addition, with a conventional nitride-based deep ultraviolet light-emitting device, only an output of several nW (nanowatts) can be realized at an emission wavelength of 210 nm. However, according to the present invention, an output of 1 W or more can also be realized.

  The deep ultraviolet light emitting device of the present invention has a very simple structure and is easy to manufacture. That is, the conventional nitride-based deep ultraviolet light-emitting device takes 1 week or more to manufacture, whereas the deep ultraviolet light-emitting device of the present invention can be manufactured in about 1 to 2 days. Also, the area can be easily increased.

  Further, when AlGaN is used as the light emitting layer, deep ultraviolet light can be generated over a predetermined wide wavelength band by spatially changing the proportion of Al in the light emitting layer.

  In addition, if a direct current voltage is applied to the electrode, deep ultraviolet light having a temporally stable intensity can be generated, so that it can be used for measurement applications.

It is sectional drawing which shows schematic structure of the deep ultraviolet light emitting element which concerns on embodiment of this invention. It is a graph which shows the relationship between discharge start voltage V, electrode space | interval d, and gas pressure p. It is a graph which shows the ratio of the ratio of Al in GaAlN, and the light emission wavelength. It is sectional drawing which shows schematic structure of the deep ultraviolet light emitting element which concerns on another embodiment of this invention.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, embodiments of the invention will be described with reference to the accompanying drawings.

  FIG. 1 is a cross-sectional view showing a schematic configuration of a deep ultraviolet light emitting element (hereinafter also simply referred to as a light emitting element) 1 according to an embodiment of the present invention. The light-emitting element 1 includes a lower substrate 2, an electrode 3 formed on the lower substrate 2, a dielectric layer 4 that covers the electrode 3 and is formed on the lower substrate 2, and an upper surface of the dielectric layer 4. The protective layer 5, the upper substrate 6, and the light emitting layer 7 formed on the upper substrate 6 so as to face the protective layer 5 are configured to form a sealed space 8.

  The distance d between the adjacent electrodes 3 is, for example, about 300 μm, and the distance between the protective layer 5 and the light emitting layer 7 is, for example, about 300 μm. The electrode 3 is made of, for example, gold.

  The sealed space 8 is filled with a gas for generating microplasma, for example, a mixed gas of Xe and Ne (volume ratio of Xe is about 5%). The operation of plasma generation will be described later, but the voltage (discharge start voltage) V at which discharge starts when a voltage is applied to the electrode 3 is determined by the distance d between the electrodes 3 and in the sealed space 8 as shown in FIG. Depends on gas pressure p. The horizontal axis represents the product of the gas pressure p and the electrode interval d, and the vertical axis represents the discharge start voltage V. Therefore, it is desirable to design the electrode interval d, the gas pressure p, and the voltage applied to the electrodes so that the discharge start voltage V can be used under the minimum conditions.

  The lower substrate 2 is, for example, a glass substrate. The upper substrate 6 is a substrate that is transparent to deep ultraviolet light, and is, for example, a single crystal sapphire substrate.

  The dielectric layer 4 is made of, for example, glass.

  The protective layer 5 is, for example, magnesium oxide (MgO).

  The light emitting layer 7 is, for example, a single crystal AlGaN layer having a thickness of about 1 μm. Note that in this specification, the expression AlGaN includes a composition that does not contain either Al or Ga. That is, AlGaN includes AlN and GaN.

Next, the operation of generating DUV light by the light emitting element 1 will be described.
A high frequency voltage is applied to the adjacent electrode 3 from an external power source (not shown). For example, a voltage having a frequency of about 15 to 20 kHz is applied. As a result, an electromagnetic field that fluctuates between adjacent electrodes 3 is formed, and the enclosed gas generates microplasma P by the electromagnetic field. DUV light L is generated from the light emitting layer 7 by the generated microplasma P, and the DUV light L is radiated to the outside through the upper substrate 6.

  FIG. 3 is a graph showing the result of simulating the wavelength of light generated by changing the proportion of Al in AlGaN. Here, the ratio of Al is the number of Al atoms / (the number of Ga atoms + the number of Al atoms). In FIG. 3, the point where the Al ratio is 0 corresponds to GaN, and the point where the Al ratio is 1 corresponds to AlN. As can be seen from FIG. 3, since the wavelength of the generated light depends on the proportion of Al in AlGaN, for example, to generate about 254 nm DUV light emitted from a mercury lamp, the proportion of Al is about 0.6. You can do it. Thus, when AlGaN is employed as the light emitting layer 7 in the light emitting element 1, DUV light having an arbitrary wavelength of about 200 to about 360 nm can be generated by adjusting the ratio of Al.

  Further, if AlGaN is adopted as the light emitting layer 7 in the light emitting element 1 and the light emitting layer 7 is formed so that the Al ratio spatially changes including the vertical direction or the horizontal direction, DUV light having a plurality of wavelengths, predetermined It is possible to generate DUV light having a continuous wavelength over a band. For example, AlGaN may be formed so that the Al concentration changes in the surface direction of the light emitting layer 7 (or in the direction perpendicular to the surface).

  Next, a manufacturing method of the deep ultraviolet light emitting element 1 according to the embodiment of the present invention will be described. In this manufacturing method, after the upper structure and the lower structure are separately manufactured, they are joined.

  In the production of the upper structure, the upper substrate 6 (for example, a sapphire substrate) is placed in a vacuum chamber, and the light emitting layer 7 is formed thereon. For example, a single crystal of AlGaN is formed as the light emitting layer 7 by metal organic chemical vapor deposition (MOCVD).

  In manufacturing the lower structure, first, the lower substrate 2 is placed in a vacuum chamber, and the electrode 3 is formed by a lift-off method or a direct pattern deposition method. For example, in the lift-off method, a predetermined mask pattern is formed on the lower substrate 2, a metal is deposited, the mask pattern is removed, and the remaining deposited layer is formed as the electrode 3.

  Next, the dielectric layer 4 is formed on the surface of the lower substrate 2 on the side where the electrode 3 is formed so as to cover the electrode 3 by, for example, sputtering. Depending on the material of the dielectric layer 4, it may be formed by coating or the like instead of sputtering.

  Next, the protective layer 5 (for example, MgO) is formed on the dielectric layer 4 by, for example, electron beam evaporation. Instead of electron beam evaporation, it may be formed by sputtering evaporation or the like.

Next, the semi-enclosed space is formed by joining the upper structure and the lower structure with a predetermined interval so that the electrode 3 and the light emitting layer 7 face each other. Thereafter, a predetermined gas is injected into the semi-sealed space in a vacuum state and completely sealed to form the sealed space 8.
The deep ultraviolet light emitting element 1 can be manufactured by the above.

  As described above, the present invention has been described using the embodiment, but the present invention is not limited to the above embodiment, and can be implemented with various modifications.

  FIG. 2 shows an example. A deep ultraviolet light emitting element 1 ′ according to another embodiment of the present invention shown in FIG. 2 includes a partition wall 9 for partitioning a microplasma generation region in the deep ultraviolet light emitting element 1 shown in FIG. . The partition wall 9 can suppress the diffusion of the generated microplasma in the lateral direction, and more microplasma can be diffused upward, that is, toward the light emitting layer 7, so that the luminous efficiency is further increased. be able to.

  Moreover, the space | interval of the light emitting layer 7 and the protective layer 5 is not limited to an above-described value. In the above description, the case where the distance between the light emitting layer 7 and the protective layer 5 is set relatively large (about 300 μm, which is the same as the electrode distance d) has been described in order to suppress damage to the light emitting layer 7 due to plasma. However, if the distance between the light emitting layer 7 and the protective layer 5 is made narrower than the electrode distance d so that the light emitting layer 7 is more exposed to the plasma, the light emission efficiency can be increased and the light emission of 10% or more. It is also possible to achieve efficiency. Since AlGaN is a high-strength material, it is considered that there is little damage even when exposed to plasma. In consideration of damage caused by plasma, the light emitting layer 7 may be formed relatively thick. For example, the distance between the light emitting layer 7 and the protective layer 5 (or the electrode 3) can be about 0.1 μm to 10 μm.

  Further, in order to suppress damage of the light emitting layer 7 due to plasma, a plurality of auxiliary electrodes may be provided on the surface of the light emitting layer 7 on the side of the sealed space 8. If a positive voltage is applied to the auxiliary electrode, electrons in the plasma are attracted to the light emitting layer 7 side (auxiliary electrode), and positive ions in the plasma can be moved away from the light emitting layer 7 to damage the light emitting layer 7. Can be suppressed. The arrangement pattern of the plurality of auxiliary electrodes is not particularly limited, but it is desirable to arrange them in a uniform distribution on the surface of the light emitting layer 7. Note that since the light emission efficiency (external quantum efficiency) decreases as the size of the auxiliary electrode increases, it is desirable to form a small auxiliary electrode. That is, it is desirable to design the size of the auxiliary electrode so that the luminous efficiency when the auxiliary electrode is provided is a value within an allowable range that does not greatly decrease from the luminous efficiency when the auxiliary electrode is not provided.

  The light emitting layer 7 may be a superlattice. If it is a superlattice, the luminous efficiency can be further increased. In this case, a protective film may be formed on the light emitting layer 7 of the superlattice.

  The light emitting layer 7 may be AlGaInN containing In. The proportion of In in AlGaInN can be more than 0% and not more than 100%. Here, the ratio of In is the number of In atoms / (number of Ga atoms + number of Al atoms + number of In atoms). The light emitting layer 7 may be InN, AlInN, or GaInN. In the case of AlInN and GaInN, the elements of Al and Ga can take values of 0% or more and less than 100%. When AlGaInN is used as the light emitting layer 7, light having a wavelength longer than that of deep ultraviolet light (about 200 to about 350 nm) can be generated by adjusting the proportions of Al, Ga, and In. For example, light having a wavelength of 350 nm or more, such as 420 nm, can be generated.

  The material that emits deep ultraviolet light is not limited to AlGaN, and may be any material that can emit deep ultraviolet light.

  Further, the electrode interval d is not limited to the above value. For example, the electrode spacing d may be about 10 nm to 1 μm, alternatively 1 μm to 300 μm, alternatively 300 μm to 1 mm, or more. The same applies to the width and height of the electrodes.

  Moreover, the shape and arrangement | positioning of the electrode 3 should just be a shape and arrangement | positioning which can generate a plasma as uniformly as possible on the substantially whole surface of the light emitting layer 7. FIG. For example, point electrodes may be arranged in a grid pattern, linear electrodes may be arranged in a stripe pattern, or comb-shaped electrodes may be arranged with comb teeth facing each other.

  Further, the applied voltage for generating plasma is not limited to the above-described RF wave, and may be a microwave. According to the frequency to be used, an appropriate applied voltage can be set according to the electrode interval d, the type of gas, and the pressure. For example, a DC voltage may be applied. In that case, the dielectric layer 4 and the protective layer 5 are not provided, and the electrode 3 may be in direct contact with the gas in the sealed space. Also in the case of a DC voltage, an appropriate applied voltage may be used depending on the electrode interval d, the type of gas, and the pressure. For example, a DC voltage of 100 to 150 V or more or less depending on the electrode interval or the sealing gas pressure. Voltage can be used. If a DC voltage is used, temporal variation of light emission due to an AC voltage such as an RF wave can be suppressed, and it can be used for measurement applications that require a certain output. The applied voltage for generating plasma may be a voltage obtained by adding a DC voltage and an AC voltage (a voltage obtained by biasing an AC voltage with a DC voltage).

  Further, the lower substrate, the electrode, the dielectric layer, the protective layer, the light emitting layer, the upper substrate, and the sealed gas are not limited to the materials described above, and can be variously changed.

  The upper substrate is not limited to sapphire, but may be any material that is highly permeable to deep ultraviolet light and can easily form a light emitting layer. For example, AlN or quartz may be used.

  Moreover, AlGaN used as the light emitting layer 7 is not limited to a single crystal, but may be polycrystalline, amorphous, or a deposited film. The light emitting layer 7 may be diamond capable of emitting deep ultraviolet light, rare earth doped AlGaN, rare earth doped SiC, ZnO, ZnMnO, or boron nitride.

  Further, the protective layer 5 or the dielectric film 4 may be made of AlN or the same composition as the light emitting layer, for example, AlGaN or each of the above materials. If AlN is used for the protective layer 5, DUV light having a wavelength of about 200 nm can also be generated from the protective layer 5.

  The protective layer 5 is a layer formed of a material selected from the group consisting of MgO, AlN, AlGaN and AlGaInN, or a layer formed by mixing these materials, and further, these layers are laminated. It may be a layer formed as a result. Moreover, a certain kind of material may be doped in these layers in the range of several ppm to several%.

  Since the lower substrate 2, the electrode 3, the dielectric layer 4, and the protective layer 5 are not positioned in the DUV light extraction direction, it is not necessary to be formed of a translucent material. The electrode 3 only needs to be formed of a conductive material, and all metals such as Al, Cr, NiCu can be used. The dielectric layer 4 and the protective layer 5 should just be formed with the electrically insulating material. If the dielectric layer 4 has sufficient strength against plasma, the protective layer 5 may not be provided.

  Moreover, the ultraviolet light emitting device of the present invention may be formed in an arbitrary size or may be formed in a curved surface shape. For example, the surfaces of the upper substrate 6 and the lower substrate 2 may be formed in a curved surface shape. Further, the surface of the upper substrate 6 on the side where the light emitting layer 7 is formed and the surface from which light exposed to the atmosphere is extracted are a surface having a special shape such as a flat surface, a convex surface, a concave surface, a columnar shape or a wall shape, or a random surface. An arbitrary shape such as a surface on which a simple structure is formed may be used. Further, when the lower substrate is formed so as to be aligned with the upper substrate, one surface or both surfaces of the lower substrate 2 are formed in the same manner.

  Further, the space formed by arranging the upper substrate 6 and the lower substrate 2 so that the electrode 3 and the light emitting layer 7 face each other (corresponding to the sealed space 8) may not be sealed, and gas flows in. You may have a means to make.

  Moreover, the deep ultraviolet light emitting device of the present invention can be used in a temperature environment of −50 ° C. to 100 ° C. When used in a high temperature environment, it is desirable to form a metal or other thermally conductive material in a structure in close contact with the upper substrate 6 or the lower substrate 5 in order to prevent temperature rise of the deep ultraviolet light emitting element. .

  In addition, in order to make the plasma stronger, magnetic field generating means such as ferrite can be brought into close contact with the electrode side to increase luminous efficiency. For example, a magnetic field is generated by passing an electric current through a coil, and the probability that the magnetic and magnetic movement of the electrons and ions will bend and collide with non-plasma gas will increase, and the plasma concentration will increase. Instead of passing a current through the coil, a permanent magnetic field such as ferrite may be used. More specifically, it is possible to use a magnetic field generated by applying a current to a coil pattern formed by attaching a ferrite plate to the back side of the lower electrode or depositing a metal, and applying a current from a ferrite or a coil. .

DESCRIPTION OF SYMBOLS 1, 1 'Deep ultraviolet light emitting element 2 Lower substrate 3 Electrode 4 Dielectric layer 5 Protective layer 6 Upper substrate 7 Light emitting layer 8 Sealed space 9 Partition P Microplasma L Deep ultraviolet light (DUV light)
d Electrode spacing

Claims (30)

An upper substrate;
A lower substrate,
A plurality of electrodes formed on one surface of the lower substrate;
A light emitting layer formed on one surface of the upper substrate;
A dielectric layer formed on the one surface of the lower substrate so as to cover the electrode;
A protective layer made of at least one material selected from the group consisting of MgO, AlN, AlGaN, and AlGaInN on the dielectric layer, or the doped protective layer;
The upper substrate and the lower substrate include a gas filled in a space formed by arranging the electrode and the light emitting layer to face each other.
The deep ultraviolet light emitting element, wherein the light emitting layer emits deep ultraviolet light by plasma generated by the gas when an alternating voltage is applied between the electrodes. An upper substrate;
A lower substrate,
A plurality of electrodes formed on one surface of the lower substrate;
A light emitting layer formed on one surface of the upper substrate;
The upper substrate and the lower substrate include a gas filled in a space formed by arranging the electrode and the light emitting layer to face each other.
The electrode is exposed to the gas;
The deep ultraviolet light emitting element characterized in that the light emitting layer emits deep ultraviolet light by plasma generated by the gas when a DC voltage is applied between the electrodes. An upper substrate;
A lower substrate,
A plurality of electrodes formed on one surface of the lower substrate;
A light emitting layer formed on one surface of the upper substrate;
The upper substrate and the lower substrate include a gas filled in a space formed by arranging the electrode and the light emitting layer to face each other.
The plasma generated by the gas when a voltage is applied between the electrodes, and emitting the light emitting layer is deep ultraviolet light,
The upper substrate is formed of sapphire;
A deep ultraviolet light emitting device , wherein the light emitting layer is formed of AlGaN, doped AlGaN, diamond capable of emitting deep ultraviolet, doped SiC, ZnO, ZnMnO, or boron nitride . An upper substrate;
A lower substrate,
A plurality of electrodes formed on one surface of the lower substrate;
A light emitting layer formed on one surface of the upper substrate;
A gas filled in a space formed by disposing the upper substrate and the lower substrate so that the electrode and the light emitting layer are opposed to each other ;
A small auxiliary electrode formed on the space side surface of the light emitting layer ,
The light emitting layer emits deep ultraviolet light by the plasma generated by the gas when a voltage is applied between the electrodes,
Deep ultraviolet light emission characterized in that, by applying a positive voltage to the auxiliary electrode and attracting electrons in the plasma generated in the space, positive ion components in the plasma generated in the space are moved away from the light emitting layer. element. An upper substrate;
A lower substrate,
A plurality of electrodes formed on one surface of the lower substrate;
A light emitting layer formed on one surface of the upper substrate;
The upper substrate and the lower substrate include a gas filled in a space formed by arranging the electrode and the light emitting layer to face each other.
The plasma generated by the gas when a voltage is applied between the electrodes, and emitting the light emitting layer is deep ultraviolet light,
The surface of the upper substrate on which the light emitting layer is formed, and at least one surface of the surface of the upper substrate from which light is extracted, one surface of the lower substrate, or both surfaces are planar, A deep ultraviolet light emitting element characterized by being a convex surface, a concave surface, a surface having a columnar portion, a surface having a wall-like portion, or a surface having a random height . An upper substrate;
A lower substrate,
A plurality of electrodes formed on one surface of the lower substrate;
A light emitting layer formed on one surface of the upper substrate;
The upper substrate and the lower substrate include a gas filled in a space formed by arranging the electrode and the light emitting layer to face each other.
The plasma generated by the gas when a voltage is applied between the electrodes, and emitting the light emitting layer is deep ultraviolet light,
A deep ultraviolet light emitting element, wherein a metal or a heat conductive material for preventing a temperature rise is adhered to the upper substrate or the lower substrate . An upper substrate;
A lower substrate,
A plurality of electrodes formed on one surface of the lower substrate;
A light emitting layer formed on one surface of the upper substrate;
The upper substrate and the lower substrate include a gas filled in a space formed by arranging the electrode and the light emitting layer to face each other.
The deep ultraviolet light emitting element, wherein the light emitting layer emits deep ultraviolet light by plasma generated by the gas when a voltage obtained by adding a direct current voltage and an alternating current voltage is applied between the electrodes. An upper substrate;
A lower substrate,
A plurality of electrodes formed on one surface of the lower substrate;
A light emitting layer formed on one surface of the upper substrate;
The upper substrate and the lower substrate include a gas filled in a space formed by arranging the electrode and the light emitting layer to face each other.
The plasma generated by the gas when a voltage is applied between the electrodes, and emitting the light emitting layer is deep ultraviolet light,
The light emitting layer is formed of AlGaInN;
The deep ultraviolet light emitting element, wherein the deep ultraviolet light is light having a wavelength within a range of 350 nm or less and 100 nm or more . An upper substrate;
A lower substrate,
A plurality of electrodes formed on one surface of the lower substrate;
A light emitting layer formed on one surface of the upper substrate;
A gas filled in a space formed by disposing the upper substrate and the lower substrate so that the electrode and the light emitting layer are opposed to each other ;
Means for generating a magnetic field in the space filled with the gas, formed in the vicinity of the electrode ,
The light emitting layer emits deep ultraviolet light by the plasma generated by the gas when a voltage is applied between the electrodes,
The deep ultraviolet light emitting element , wherein the plasma is increased by the magnetic field generated by the means . A dielectric layer formed on the one surface of the lower substrate so as to cover the electrode;
10. The deep ultraviolet light-emitting element according to claim 3, wherein the voltage applied between the electrodes is an alternating voltage. The protective layer made of at least one material selected from the group consisting of MgO, AlN, AlGaN, and AlGaInN or the doped protective layer is provided on the dielectric layer. 10. A deep ultraviolet light-emitting device according to 10. The electrode is exposed to the gas;
The deep ultraviolet light-emitting element according to any one of claims 3 to 6, 8, and 9, wherein a voltage applied between the electrodes is a DC voltage. Wherein the plasma generated in response to each of the electrode pairs to be applied to the voltage, to any one of claim 1 to 12, further comprising a partition wall for spaced from each other Deep ultraviolet light emitting device. The upper substrate is formed of sapphire;
Claim 1, wherein the light emitting layer, AlGaN, characterized in that it is formed by doped AlGaN, diamond can emit deep ultraviolet, doped SiC, ZnO, ZnMnO, or boron nitride, 2,4～9 The deep ultraviolet light emitting element of any one of these. 15. The deep ultraviolet light-emitting element according to claim 14 , wherein the light-emitting layer is made of superlattice AlGaN. The light emitting layer is AlGaN,
The deep ultraviolet light-emitting element according to claim 14 or 15 , wherein a ratio of Al in the light-emitting layer changes along a plane of the light-emitting layer or in a direction perpendicular to the plane of the light-emitting layer. The distance between the light emitting layer and the electrode, a deep ultraviolet light-emitting device according to any one of claim 1 to 16, characterized in that narrower than the distance between the electrode pairs to be applied to said voltage. It said gas, Xe, Ne, He, Ar , claim 1-17, characterized in that at least one gas or a mixture gas selected from the group consisting of _{N 2} and _{H 2} 2. A deep ultraviolet light emitting device according to item 1. A micro auxiliary electrode is provided on the space side surface of the light emitting layer,
The positive ion component in the plasma generated in the space is moved away from the light emitting layer by applying a positive voltage to the auxiliary electrode and attracting electrons in the plasma generated in the space. The deep ultraviolet light-emitting device according to any one of to 3 and 5 to 9 . Distance between the adjacent electrodes, spacing of the electrodes and the light emitting layer, the width of the electrode, or the height of the electrodes, 300 [mu] m or less, or claims 1-19, characterized in that the 300μm~1mm The deep ultraviolet light-emitting device according to any one of the above. 21. The deep ultraviolet light emitting element according to claim 20 , wherein at least one of an interval between the adjacent electrodes and an interval between the electrode and the light emitting layer is 1 μm or less. Wherein at least one of the dielectric layer and the protective layer, a deep ultraviolet light emitting device according to claim 1 or 11, characterized in that it is formed of a material having the same composition as the light emitting layer. The surface of the upper substrate on which the light emitting layer is formed, and at least one surface of the surface of the upper substrate from which light is extracted, one surface of the lower substrate, or both surfaces are planar, The deep ultraviolet according to any one of claims 1 to 22 , which is a convex surface, a concave surface, a surface having a columnar portion, a surface having a wall-like portion, or a surface having a random height. Light emitting element. The gas is enclosed in the sealed space, or
The deep ultraviolet light emitting element according to any one of claims 1 to 23 , further comprising means for causing the gas to flow into the space. The deep ultraviolet light emission according to any one of claims 1 to 5 , and 7 to 9 , wherein a metal or a heat conductive material for preventing a temperature rise is adhered to the upper substrate or the lower substrate. element. The deep ultraviolet light-emitting element according to any one of claims 3 to 6, 8, and 9, wherein the voltage is a voltage obtained by adding a DC voltage and an AC voltage. The light emitting layer is formed of AlGaInN;
The deep ultraviolet light, deep ultraviolet light emitting device according to any one of claims 1 to 7 and 9, characterized in that the light having a wavelength in the range of more or less 100 nm 350 nm. Means for generating a magnetic field in the space filled with the gas in the vicinity of the electrode;
The deep ultraviolet light emitting element according to any one of claims 1 to 8 , wherein the plasma is increased by the generated magnetic field. A first step of forming a light emitting layer on one surface of the upper substrate;
A second step of forming a plurality of electrodes on one surface of the lower substrate;
A third step in which the electrode and the light emitting layer are opposed to each other and the upper substrate and the lower substrate are joined at a predetermined interval to form a space;
And a fourth step of enclosing gas in the space,
The light emitting layer is AlGaN;
The method of manufacturing a deep ultraviolet light emitting element, wherein the gas is a gas that generates plasma when a voltage is applied between the electrodes. The first step is a step of forming the light emitting layer so that a ratio of Al in the light emitting layer changes in a plane direction of the light emitting layer or in a direction perpendicular to a plane of the light emitting layer. Item 30. A method for producing a deep ultraviolet light emitting device according to Item 29 .

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