Light emitting element and light irradiation device

Abstract

To provide an electron beam excitation type light emitting element which is easy to assemble and can be mounted on a mounting board such as a printed board, and to provide a light irradiation device including the light emitting element.SOLUTION: The light-emitting element 10 includes an electron beam source 11 and a light-emitting portion 21, the light-emitting portion 21 is mounted on a bottom substrate 31, the electron beam source 11 is supported by a sub-substrate 60 fixed to the bottom substrate 31 at a position away from the light-emitting portion 21 in a direction along a surface of the bottom substrate 31 and in a direction along a vertical direction of the bottom substrate 31 in a posture inclined toward the light-emitting portion 21, and the light-emitting element 10 has a contour portion 51 that surrounds the electron beam source 11, the light-emitting portion 21, and the sub-substrate 60 and maintains the inside in a vacuum. An irradiation window 52 is provided in a portion of the outer portion 51 facing the light emitting unit 21.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a light-emitting element and a light irradiation device. [Background technology]

[0002] Development of electron beam excited light emitting devices comprising an electron beam source and a light emitting layer excited by the electron beam of the electron beam source is progressing (e.g., Patent Documents 1 to 3). This type of light emitting device is expected to serve as a light source of deep ultraviolet light suitable for disinfection, sterilization, sterilization, surface modification, etc. Patent Document 1 proposes a configuration for the purpose of combining an electron beam source and a light emitting layer excited by the electron beam of the electron beam source into an element or modularization. The configuration involves placing a glass plate on an electron emitting element, and laminating a gold-evaporated surface and a hexagonal boron nitride thin film on the glass plate, thereby forming a cathode attached to the back surface of the electron emitting element substrate and a Ti / Au surface formed on the underside of the hexagonal boron nitride thin film as an anode. Patent Document 2 proposes a configuration in which a semiconductor light emitting element is placed on the bottom wall and multiple electron beam sources are attached to a pair of side walls. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2006-79873 [Patent Document 2] Japanese Patent Application Laid-Open No. 2015-46415 [Patent Document 3] Japanese Patent Publication No. 2023-55415 Summary of the Invention [Problem to be solved by the invention]

[0004] Meanwhile, it is desirable to develop an electron beam excited light emitting element that can be mounted on a substrate such as a printed circuit board in the same way as general semiconductor components. Furthermore, in the case of an excitation structure in which an electron beam source and a light-emitting layer are arranged three-dimensionally as described in Patent Document 2, the structure becomes complicated, making assembly difficult and disadvantageous to manufacturing. Therefore, an object of the present disclosure is to provide an electron beam excited light emitting element that is easy to assemble and can be mounted on a mounting substrate such as a printed circuit board, and a light irradiation device that includes the light emitting element. [Means for solving the problem]

[0005] In order to achieve the above object, there is provided a light-emitting element including an electron beam source and a light-emitting unit having a light-emitting layer excited by electron beams from the electron beam source, wherein the light-emitting unit is mounted on a substrate, and the electron beam source is supported by a sub-substrate fixed to the substrate in an inclined position toward the light-emitting unit, at a position spaced apart from the light-emitting unit in a direction along the surface of the substrate and in a direction perpendicular to the substrate, the light-emitting element having an outer casing that surrounds the electron beam source, the light-emitting unit, and the sub-substrate to maintain a vacuum inside, and an irradiation window through which light from the light-emitting unit passes, in a portion of the outer casing that faces the light-emitting unit. The present invention also provides a light irradiation device for industrial use that includes a printed circuit board on which the light emitting element is mounted, and that irradiates an object with light from the light emitting element that is arranged in a plane so as to be plane mountable. [Effects of the Invention]

[0006] According to the present invention, it is possible to provide an electron beam excited light emitting element that is easy to assemble and can be mounted on a mounting substrate such as a printed circuit board, and a light irradiation device including the light emitting element. [Brief explanation of the drawings]

[0007] [Figure 1] 1 is a diagram schematically illustrating a cross-sectional structure of a light-emitting device according to an embodiment of the present invention. [Figure 2] 1A and 1B are diagrams illustrating the light emission principle of a light-emitting element. [Figure 3] FIG. 1 is a diagram showing wavelength transmission characteristics of a CNT conductive film. [Figure 4] FIG. [Figure 5] FIG. 2 is a perspective view showing a state in which an outer shell part is removed from the light emitting element. [Figure 6] FIG. 6 is an exploded perspective view of FIG. 5. [Figure 7] FIG. 2 is a perspective view showing the light emitting element from below. [Figure 8] FIG. 2 is a diagram showing the structure of an electron beam source together with its surrounding structure. [Figure 9] FIG. 2 is a diagram showing the structure of a light-emitting portion together with the surrounding structure. [Figure 10] 1A to 1C are diagrams showing a number of modes in which a light emitting element is mounted on a mounting substrate. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Fig. 1 is a diagram schematically showing the cross-sectional structure of a light-emitting element 10 according to this embodiment, and Fig. 2 is a diagram showing the light-emitting principle of the light-emitting element 10. 1, the light-emitting element 10 of this embodiment is configured to include an electron beam source 11, a light-emitting section 21 having a light-emitting layer 21L (FIG. 2) excited by electron beams from the electron beam source 11, an anode electrode 41 (FIG. 2) to which a high voltage is applied, a substrate 31 on which the light-emitting section 21 is mounted, and an outer casing 51 that surrounds these components, and is formed into a device and packaged. The internal space surrounded by the outer casing 51 and the substrate 31 is a vacuum.

[0009] The electron beam source 11 is supported by a sub-substrate 60 provided on the substrate 31. The sub-substrate 60 is fixed to an upper surface 31A, which corresponds to the mounting surface of the substrate 31. The sub-substrate 60 supports the electron beam source 11 in a position inclined toward the light-emitting unit 21, at a distance from the light-emitting unit 21 in a direction along the surface of the substrate 31 (corresponding to the lateral direction) and in a direction along the vertical direction of the substrate 31 (corresponding to the up-down direction).

[0010] In this configuration, the central axis 11C of the electron beam source 11 (corresponding to a vertical line passing through the center of the electron beam irradiation surface) is preferably positioned so as to intersect with the center 21C of the light emitting surface of the light emitting part 21. Furthermore, the range Sa of the electron beam irradiation surface of the electron beam source 11 is larger than or equal to the range Sb of the light-emitting surface of the light-emitting unit 21 extending parallel to the central axis 11C of the electron beam source 11. In other words, the electron beam irradiation surface of the electron beam source 11 is larger than or equal to the projection range Sb of the light-emitting surface projected onto the electron beam source 11. This arrangement is realized by, for example, setting the positional relationship between the electron beam source 11 and the light-emitting unit 21 using the sub-substrate 60. This arrangement allows the electron beams from the electron beam source 11 to be efficiently incident on the light-emitting surface of the light-emitting unit 21.

[0011] 1 shows that, in a side cross-sectional view of the light-emitting element 10, the central axis 11C of the electron beam source 11 intersects with the center 21C of the light-emitting surface of the light-emitting unit 21, and the range Sa of the electron beam irradiation surface of the electron beam source 11 is wider than the projection range Sb of the light-emitting surface projected onto the electron beam source 11. In this embodiment, also in a top view of the light-emitting element 10, the central axis 11C of the electron beam source 11 intersects with the center 21C of the light-emitting surface of the light-emitting unit 21, and the range Sa of the electron beam irradiation surface of the electron beam source 11 is wider than the projection range Sb of the light-emitting surface. Therefore, the electron beams from the electron beam source 11 can be efficiently incident on the entire light-emitting surface of the light-emitting unit 21, enabling uniform and highly efficient light emission.

[0012] A cathode terminal TC, a gate terminal TG, and an anode terminal TA are provided on a lower surface 31B, which corresponds to the back surface of the substrate 31. The light-emitting element 10 configured in this manner can be said to be an electron-beam-excited light-emitting element and an electron-beam-excited light-emitting element package. An opening 51K is formed in outer shell 51 in a region facing the light-emitting surface of light-emitting unit 21, and opening 51K is closed by irradiation window 52. Irradiation window 52 is made of, for example, synthetic quartz, and transmits light from light-emitting unit 21. For irradiation window 52, ​​any light-transmitting material that can transmit light from light-emitting unit 21 (such as MgF2 (magnesium fluoride), Al2O3 (sapphire), CaF2 (calcium fluoride), SiO2 (synthetic quartz / fused silica), or LiF (lithium fluoride)) can be used.

[0013] 2, the electron beam source 11 emits electrons when a predetermined voltage Va is applied to it. The value of the voltage Va is, for example, 10 to 30V. The anode electrode 41 is provided so as to overlap the light-emitting layer 21L. Therefore, in the following description, the anode electrode 41 is assumed to be provided in the light-emitting section 21.

[0014] The light-emitting section 21 has a laminated structure of a first thin film functioning as the light-emitting layer 21L and a second thin film functioning as the anode electrode 41, and is formed in a planar shape on a base (film-forming base) 21B. The anode electrode 41 accelerates the electron beam generated by the electron beam source 11 in a vacuum space (acceleration space) when an acceleration voltage Vb is applied to it. The anode electrode 41 is also called an extraction electrode that accelerates the electron beam. The acceleration voltage Vb is a high voltage, for example, 1 to 15 kV.

[0015] The first thin film is a light-emitting layer that emits deep ultraviolet light when irradiated with an electron beam, and the light from the light-emitting layer is emitted to the outside through the irradiation window 52 shown in Fig. 1. By using a thin film of magnesium zinc oxide (MgZnO) or hexagonal boron nitride (hBN) for the first thin film (light-emitting layer 21L), it is possible to emit deep ultraviolet light having a peak wavelength in the shorter wavelength range of ultraviolet light.

[0016] The second thin film (anode electrode 41) is formed of a CNT (carbon nanotube) conductive film. Figure 3 shows the wavelength transmission characteristics of the CNT conductive film. As shown in Figure 3, the CNT conductive film has a transmittance of 70% or more in the low wavelength band (200 nm wavelength and the surrounding wavelength band) that includes deep ultraviolet light, and can transmit deep ultraviolet light more efficiently than other conductive films such as transparent conductive films (ITO, etc.).

[0017] Furthermore, the high electrical conductivity and electron emission properties of the CNT conductive film allow the electron beam to be efficiently transmitted to the light-emitting layer 21L, facilitating highly efficient light emission. Furthermore, the CNT conductive film has high mechanical strength and chemical stability, which is advantageous for improving the durability and reliability of the electron beam source 11.

[0018] The electron beam source 11 and the light-emitting unit 21 can be easily manufactured using semiconductor microfabrication techniques, and are easily miniaturized. Semiconductor microfabrication techniques include photolithography, etching, and thin film formation. Furthermore, the light-emitting element 10 emits deep ultraviolet light, making it suitable for disinfection, sterilization, sterilization, and surface modification.

[0019] However, the materials and structures of the electron beam source 11 and the light-emitting unit 21 may be changed as appropriate within the scope of feasible manufacturing methods using semiconductor microfabrication techniques. For example, the material of the first thin film may be changed as appropriate to irradiate light other than deep ultraviolet light. Furthermore, the light-emitting layer 21L does not have to be limited to a thin film.

[0020] Next, the specific structure of the light emitting element 10 will be described. FIG. 4 shows a perspective view of the light emitting device 10. As shown in FIG. The light-emitting element 10 has a rectangular parallelepiped outer shell 51 that surrounds the electron beam source 11 from above. The outer shell 51 has an opening 51K that opens in the vertical direction, and the opening 51K is closed by an irradiation window 52. The substrate 31 forms the bottom portion of the light-emitting element 10, so the substrate 31 can also be called a bottom substrate. The substrate 31 can also be called a main substrate. In the following description, the substrate 31 will be referred to as a bottom substrate 31.

[0021] Fig. 5 is a perspective view showing a state in which the outer shell 51 is removed from the light emitting element 10. Fig. 6 is an exploded perspective view of Fig. 5. Fig. 7 is a perspective view showing the light emitting element 10 from below. As shown in Fig. 5, bottom substrate 31 is formed of an insulating substrate such as a flat ceramic substrate, and light-emitting unit 21 is mounted on top surface 31A of bottom substrate 31. A plurality of sub-substrate contacts PC and PG (hereinafter referred to as cathode contact PC and gate contact PG) and an anode contact PA are provided on top surface 31A of bottom substrate 31, as shown in Fig. 6. Sub-substrate 60 is attached at positions corresponding to cathode contact PC and gate contact PG.

[0022] A groove 31M into which the lower part of the outer shell 51 fits is formed around the periphery of the upper surface 31A of the bottom substrate 31, and the groove 31M positions the outer shell 51. The gap between the groove 31M and the outer shell 51 is closed by a predetermined bonding material that bonds the outer shell 51 to the bottom substrate 31. The predetermined bonding material is, for example, glass frit.

[0023] 5 and 6, the sub-substrate 60 includes a columnar insulating member standing on the bottom substrate 31. The sub-substrate 60 has a pattern surface 61 on the side facing the electron beam source 11, to which the electron beam source 11 is attached. Sub-substrate 60 is formed of an insulating substrate such as a ceramic substrate, and pattern surface 61 of sub-substrate 60 is formed by metallizing the substrate surface (e.g., a non-metallic surface such as ceramic) of the substrate. The metal film is, for example, an Au-plated copper conductor commonly used in wiring patterns, but is not limited to this and may be formed of other metal members. In this way, sub-substrate 60 including pattern surface 61 can be formed using semiconductor microfabrication technology.

[0024] A slit 61s extending in the vertical direction is formed on the side surface of the sub-substrate 60. The pattern surface 61 of the sub-substrate 60 has a first pattern surface 61a, to which the electron beam source 11 is attached, on one side across the slit 61s, and a second pattern surface 61b, to which the wire W1 extending from the first pattern surface 61a is connected, on the other side across the slit 61s. The first pattern surface 61a forms a conductive path that electrically connects the electron beam source 11 to the cathode contact PC (FIG. 6). The second pattern surface 61b forms a conductive path that electrically connects the electron beam source 11 to the gate contact PG (FIG. 6) via the wire W1. Note that these pattern surfaces 61a and 61b do not have to be limited to a configuration formed from a thin film.

[0025] The pattern surface 61 has an inclined surface 61k (FIG. 5) that is inclined toward the light-emitting unit 21 mounted on the bottom substrate 31, and the electron beam source 11 is provided in the region of the first pattern surface 61a of the inclined surface 61k. As a result, the electron beam source 11 is supported at a position apart from the light-emitting unit 21 laterally and above the light-emitting unit 21, in a position inclined obliquely toward the light-emitting unit 21.

[0026] As shown in FIG. 1, the cathode contact PC and the gate contact PG are electrically connected to a cathode terminal TC and a gate terminal TG, respectively, provided on the lower surface 31B of the bottom substrate 31 by via structures ST1 and ST2, such as multilayer laminated conductor wiring and through-hole vias, that penetrate the bottom substrate 31. 1, the anode contact PA is electrically connected to an anode terminal TA provided on the lower surface 31B of the bottom substrate 31 by a multilayer laminated conductor wiring and via structure ST3, such as a through-hole via, that penetrates the bottom substrate 31. Note that the multilayer laminated wiring portion is omitted from the drawings as appropriate.

[0027] 7, an anode terminal TA is provided on the lower surface 31B of the bottom substrate 31 at a constant width in an area on one of the two opposing sides of the substrate 31. A cathode terminal TC and a gate terminal TG are provided on the other side at a constant interval. On the lower surface 31B of the substrate 31, the anode terminal TA to which a high voltage is applied can be effectively separated from other conductive patterns (the cathode terminal TC and the gate terminal TG), thereby ensuring an insulation distance (creepage distance and spatial distance) between the anode terminal TA and other conductive patterns.

[0028] FIG. 8 is a diagram showing the structure of the electron beam source 11 together with the surrounding structure. 8, the electron beam source 11 has a MIM (Metal / Insulator / Metal) structure in which an insulator (e.g., an insulating film) is sandwiched between an upper electrode 11A and a lower electrode 11B, or a MIS (Metal / Insulator / Semiconductor) structure in which an oxide (e.g., an oxide film) is sandwiched between the upper electrode 11A and the lower electrode 11B, and is formed as a planar electron beam source. In Fig. 8, the portion (insulating film or oxide film) between the upper electrode 11A and the lower electrode 11B is indicated by the reference numeral 11C.

[0029] The lower electrode 11B corresponds to a cathode electrode, and an electrode layer M1 is formed on the surface by metal vapor deposition of gold or the like, and is joined to the first pattern surface 61a with a metal joining material MB1 made of a solder material or a metal brazing material. The upper electrode 11A corresponds to a gate electrode having a positive potential with respect to the cathode electrode, and is electrically connected to the second pattern surface 61b using a metal wire W1 (conductive member). Electrons are emitted when a predetermined voltage Va (FIG. 2) is applied between the upper electrode 11A and the lower electrode 11B. Note that the upper electrode 11A and the second sub-substrate portion 61b may be connected by a method other than wire bonding.

[0030] A slit 61s is provided between the first pattern surface 61a and the second pattern surface 61b. The slit 61s functions as an insulating groove between the anode terminal TA and the gate terminal TG. The slit 61s also extends to the underside of the sub-substrate 60 and is designed to fit into the grooves of the cathode contact PC and the gate contact PG provided on the surface of the bottom substrate 31A.

[0031] Graphene may be used for the upper electrode 11A to suppress scattering of electrons by the upper electrode 11A. For example, graphene can be formed on an insulating film by chemical vapor deposition (CVD). Employing a layered structure (which can be called a GOS structure) consisting of graphene / oxide film / silicon (Graphene / Oxide / Semiconductor) for the electron beam source 11 can further improve the electron emission efficiency.

[0032] That is, any one of a GOS (Graphene / Oxide / Semiconductor) electron beam source, an MIM electron beam source, and an MIS electron beam source is adopted as the electron beam source 11 of this configuration, which enables highly accurate electron emission, highly efficient operation, and a long life. More specifically, GOS electron beam sources utilize graphene oxide sheets, which have excellent electrical conductivity and carrier mobility, enabling highly efficient electron emission. Furthermore, graphene oxide sheets are chemically stable, resulting in excellent durability. MIM electron beam sources utilize a metal-insulator-metal structure to emit electrons using a quantum mechanical phenomenon known as the tunneling effect, achieving highly efficient electron emission and stability. MIM electron beam sources also have the advantages of being small, lightweight, and low-power. MIS electron beam sources utilize the properties of semiconductors to emit electrons using a metal-insulator-semiconductor structure, achieving highly efficient electron emission and stability. The energy and intensity of the electron beam can be adjusted by controlling the gate voltage.

[0033] Furthermore, MIM electron beam sources, MIS electron beam sources, and GOS electron beam sources tend to have smaller electron beam divergence angles and higher directionality than other electron beam sources. This is because the electrons tunnel through a solid, so they are not affected by the degree of vacuum, and because electrons can be emitted from a flat surface, the electron divergence angle is reduced (see Reference 1, for example). Utilizing this characteristic enables highly efficient excitation.

[0034] Reference 1: Masayoshi Nagao and Katsuhisa Murakami, Development of high-performance electron sources and expanding application technologies, Special feature "New developments in electron beam technology", Surface and Vacuum, 2020, Vol. 63, No. 1, pp. 7-12, https: / / doi.org / 10.1380 / vss.63.7

[0035] FIG. 9 is a diagram showing the structure of the light-emitting section 21 together with the surrounding structure. 9, the light-emitting unit 21 is configured by laminating a first thin film functioning as the light-emitting layer 21L and a second thin film made of a CNT conductive film functioning as the anode electrode 41 on a base 21B provided on the upper surface 31A of the bottom substrate 31 via a die bonding material (adhesive) G1. The anode electrode 41 is electrically connected to an anode contact PA provided on the upper surface 31A of the bottom substrate 31 using a metal wire W2 (conductive member). Note that the anode electrode 41 and the anode contact PA may be connected by a method other than wire bonding. A reflective layer may also be added between the base 21B and the light-emitting layer 21L.

[0036] The anode contact PA, cathode contact PC, and gate contact PG are formed by metallizing the base surface (e.g., a non-metallic surface such as ceramic) of the bottom substrate 31, for example, by plating Au on a copper conductor commonly used in wiring patterns. Note that the contacts PA, PC, and PG may also be formed from other metal materials (conductive members). The contacts PA, PC, and PG and the light-emitting section 21 can be formed using semiconductor microfabrication technology. Therefore, by using semiconductor microfabrication technology, it is possible to manufacture a small and thin bottom substrate 31 and light-emitting section 21.

[0037] As described above, the light-emitting element 10 of this embodiment includes the electron beam source 11 and the light-emitting unit 21, the light-emitting unit 21 is mounted on the bottom substrate 31, and the electron beam source 11 is supported by the sub-substrate 60 fixed to the bottom substrate 31 in a position inclined toward the light-emitting unit 21, at a distance from the light-emitting unit 21 in a direction along the surface of the bottom substrate 31 and in a direction along the vertical direction of the bottom substrate 31. Furthermore, the light-emitting element 10 has an outer shell 51 that surrounds the electron beam source 11, the light-emitting unit 21, and the sub-substrate 60 and maintains the inside at a vacuum, and an emission window 52 through which light from the light-emitting unit 21 passes, in a portion of the outer shell 51 facing the light-emitting unit 21.

[0038] According to this configuration, since the electron beam source 11 and the light-emitting unit 21 are attached to the bottom substrate 31, there is no need to arrange electrical wiring between the electron beam source 11 and the light-emitting unit 21 in three dimensions on different members, such as the bottom substrate 31 and the outer shell 51, resulting in a simple structure and easy assembly. Furthermore, by efficiently directing the electron beam into the light-emitting unit 21, uniform and highly efficient light emission becomes possible. Furthermore, this device can be easily manufactured using semiconductor microfabrication technology, and as shown in FIG. 10(A), it can also be mounted on a mounting substrate 100 such as a printed circuit board. That is, an electron-beam-excited light-emitting element 10 that is easy to assemble and can be mounted on a mounting substrate 100 can be obtained.

[0039] According to this configuration of the light-emitting element 10, it is not limited to the configuration in which a single light-emitting element 10 is mounted on the mounting substrate 100 as shown in Fig. 10(A), but it is also easy to configure a configuration in which a plurality of light-emitting elements 10 are mounted on the mounting substrate 100 as shown in Fig. 10(B). Moreover, it is also easy to configure a so-called multi-drive configuration in which a plurality of electron beam sources 11 and light-emitting units 21 are mounted on the bottom substrate 31 as shown in Fig. 10(C).

[0040] It is also easy to change the positions of the electron beam source 11 and the conductive paths of the terminals TC, TG, TA, etc. with respect to the bottom substrate 31. This makes it easier to ensure the insulation distance (creepage distance and spatial distance) between the anode terminal TA to which a high voltage is applied and other conductive paths.

[0041] The sub-substrate 60 also includes a pattern surface 61 electrically connected to the bottom substrate 31, and the pattern surface 61 has an inclined surface 61k that is inclined toward the light-emitting section 21, and the electron beam source 11 is provided on the inclined surface 61k. With this configuration, the electron beam source 11 can be easily provided at a position where the electron beam can be efficiently incident on the light-emitting section 21.

[0042] The light emitting unit 21 also has an anode electrode 41 to which a high voltage for accelerating the electron beam is applied, and a cathode terminal TC and a gate terminal TG electrically connected to the electron beam source 11, and an anode terminal TA electrically connected to the anode electrode 41 are arranged on a lower surface 31B corresponding to the back surface of the bottom substrate 31 in a planar manner so that the bottom substrate 31 can be planarly mounted. According to this configuration, the terminals TC, TG, and TA are arranged together on the lower surface of the bottom substrate 31, facilitating electrical connection to the mounting substrate 100.

[0043] Furthermore, since the light emitting surface of the light emitting unit 21 is flat and the central axis 11C of the electron beam source 11 intersects with the light emitting surface, the electron beam can be made incident on the light emitting surface more efficiently, which is advantageous for uniform and highly efficient light emission.

[0044] The anode electrode 41 has a CNT conductive film, and can transmit and extract deep ultraviolet light emitted from the surface excited by an electron beam.

[0045] Furthermore, the light emitting layer 21L emits light having a peak wavelength in the wavelength range of deep ultraviolet light when exposed to electron beams, and is therefore suitable for applications such as disinfection, sterilization, sterilization, and surface modification.

[0046] The above embodiment is merely an example of one aspect of the present invention, and any modifications and applications are possible without departing from the spirit of the present invention. For example, although the case where a planar electron beam source consisting of any of a GOS electron beam source, an MIM electron beam source, and an MIS electron beam source is used as the electron beam source 11 has been described, the present invention is not limited to these.

[0047] Furthermore, although the light emitting element 10 of the present invention has been described as being applied to a light emitting element that emits deep ultraviolet light, it may also be applied to a light emitting element that emits light other than deep ultraviolet light. Furthermore, the present invention may also be applied to an industrial light irradiation device that includes a mounting substrate 100 such as a printed circuit board on which the light emitting element 10 is mounted, and that irradiates an object with light from the light emitting element 10 that is arranged in a planar manner so as to be planar mountable. Examples of industrial light irradiation devices include a container sterilizer, an air sterilizer, a running water sterilizer, and a surface modification device.

[0048] The above embodiment supports the following configurations.

[0049] (Configuration 1) A light-emitting element comprising an electron beam source and a light-emitting section having a light-emitting layer excited by electron beams from the electron beam source, wherein the light-emitting section is mounted on a substrate, and the electron beam source is supported by a sub-substrate fixed to the substrate in an inclined position toward the light-emitting section, at a position spaced apart from the light-emitting section in a direction along the surface of the substrate and in a direction perpendicular to the substrate, the light-emitting element having an outer casing that surrounds the electron beam source, the light-emitting section, and the sub-substrate and maintains a vacuum inside, and an irradiation window through which light from the light-emitting section passes, in a portion of the outer casing that faces the light-emitting section. This configuration provides an electron beam excited light emitting element that is easy to assemble and mount on a mounting substrate such as a printed circuit board. Furthermore, by efficiently directing the electron beam into the light emitting portion, uniform and highly efficient light emission is possible.

[0050] (Configuration 2) The light-emitting element according to Configuration 1, wherein the sub-substrate includes a pattern surface electrically connected to the substrate, the pattern surface has an inclined surface inclined toward the light-emitting section, and the electron beam source is provided on the inclined surface. According to this configuration, the electron beam source can be easily provided at a position where the electron beam can be efficiently incident on the light-emitting portion.

[0051] (Configuration 3) The light-emitting unit has an anode electrode to which a high voltage for accelerating the electron beam is applied, and a cathode terminal and a gate terminal that are electrically connected to the electron beam source and an anode terminal that is electrically connected to the anode electrode are arranged on the back surface of the substrate in a planar manner so that the substrate can be surface-mounted. According to this configuration, the terminals are arranged together on the rear surface of the substrate, facilitating electrical connection to the mounting substrate.

[0052] (Configuration 4) The light-emitting element according to any one of configurations 1 to 3, wherein the light-emitting surface of the light-emitting portion is planar, and the central axis of the electron beam source intersects with the light-emitting surface. This configuration allows the electron beam to be incident on the light emitting surface more efficiently, which is advantageous for achieving uniform and highly efficient light emission.

[0053] (Configuration 5) The light-emitting device according to any one of configurations 1 to 4, wherein the anode electrode has a CNT conductive film. According to this configuration, deep ultraviolet light excited on the surface by an electron beam can be transmitted and extracted.

[0054] (Configuration 6) The light-emitting device according to any one of configurations 1 to 5, wherein the light-emitting layer emits deep ultraviolet light when exposed to the electron beam. This configuration is suitable for applications such as disinfection, sterilization, sterilization, and surface modification.

[0055] (Configuration 7) A light irradiation device for industrial use, comprising a printed circuit board on which the light emitting element according to any one of configurations 1 to 6 is mounted, for irradiating an object with light from the light emitting element. According to this configuration, it is possible to obtain a light irradiation device for industrial use that includes an electron beam excited light emitting element that can be easily mounted on a mounting substrate such as a printed circuit board, and that irradiates an object with light from this light emitting element. [Explanation of symbols]

[0056] 10 Light emitting element (light emitting element package) 11 Electron beam source 11A upper electrode 11B Lower electrode 21 Light-emitting part 21L Emitting layer (first thin film) 21B Base (film deposition base) 31 Substrate (bottom substrate) 31A Top surface of the board (mounting surface) 31B Bottom surface of the board (reverse surface) 41 Anode electrode (second thin film) 51 Outer wall 52 Irradiation window 60 Sub-board 61 Sub-board pattern surface 61k Sub-board inclined surface 100 Mounting board (printed circuit board) TC cathode terminal TG Gate terminal TA Anode terminal

Claims

1. A light-emitting device comprising an electron beam source and a light-emitting portion having a light-emitting layer excited by an electron beam from the electron beam source, the light emitting unit is mounted on a substrate, the electron beam source is supported by a sub-substrate fixed to the substrate at a position spaced apart from the light-emitting unit in a direction along the surface of the substrate and in a direction perpendicular to the substrate, in a position inclined toward the light-emitting unit, an outer shell that surrounds the electron beam source, the light-emitting unit, and the sub-substrate and maintains the inside in a vacuum; The outer shell has an irradiation window at a portion facing the light emitting unit, through which light from the light emitting unit passes. Light-emitting element.

2. the sub-substrate includes a pattern surface electrically connected to the substrate; The pattern surface has an inclined surface inclined toward the light-emitting portion, and the electron beam source is provided on the inclined surface. The light-emitting device according to claim 1 .

3. the light-emitting unit has an anode electrode to which a high voltage for accelerating the electron beam is applied, A cathode terminal and a gate terminal that are electrically connected to the electron beam source, and an anode terminal that is electrically connected to the anode electrode are arranged on the back surface of the substrate in a planar manner so that the substrate can be surface-mounted. The light-emitting device according to claim 1 .

4. the light-emitting surface of the light-emitting unit is flat, The central axis of the electron beam source intersects with the light-emitting surface. The light-emitting device according to claim 1 .

5. The anode electrode has a CNT conductive film. The light-emitting device according to claim 1 .

6. The light-emitting layer emits deep ultraviolet light by the electron beam. The light-emitting device according to claim 1 .

7. A printed circuit board on which the light-emitting element according to any one of claims 1 to 5 is mounted, The light irradiation device for industrial use irradiates an object with light from the light emitting element arranged in a plane so as to be surface mountable.

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