JP2005308654A - Electron source application device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electron source application device to generate an electron or ion stably without being affected by humidity in air. <P>SOLUTION: This electron source application device is provided with an electron source 10 for emitting an electron beam by a ballistic type electron emission phenomenon, and a case 20 for storing the electron source 10. The case 20 is provided with a rectangular-shaped window hole 21 in a portion opposed to the electron source, and two gas introducing ports 22 for introducing dry gas (for example, dry air, dry oxygen, inert gas or the like) supplied to a space between the window hole 21 and the electron source 10. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an electron source application apparatus including an electron source that emits an electron beam by field emission.

  Conventionally, for example, an electron source 10 ′ having a configuration shown in FIG. 13 is known as an electron source capable of emitting electrons by electric field radiation not only in a vacuum but also in an atmospheric pressure (for example, Patent Document 1, 2 and 3), an ion generator having the configuration shown in FIG. 14 has been proposed as an electron source application apparatus using the electron source 10 ′.

  In the electron source 10 ′ having the configuration shown in FIG. 13, a strong electric field drift layer 6 made of oxidized porous polycrystalline silicon is formed on the main surface (one surface) side of an n-type silicon substrate 1 as a conductive substrate. A surface electrode 7 made of a metal thin film (for example, a gold thin film) is formed on the electric field drift layer 6. An ohmic electrode 2 is formed on the back surface of the n-type silicon substrate 1, and the n-type silicon substrate 1 and the ohmic electrode 2 constitute a lower electrode 12. In addition, the thickness dimension of the surface electrode 7 is set to about 10 nm, for example. Further, in the electron source 10 ′ having the configuration shown in FIG. 13, the non-doped polycrystalline silicon layer 3 is interposed between the lower electrode 12 and the strong electric field drift layer 6, and the polycrystalline silicon layer 3 and the strong electric field drift layer are interposed. 6 constitutes an electron passage layer which is interposed between the lower electrode 12 and the surface electrode 7 and allows electrons to pass therethrough, but only the strong electric field drift layer 6 does not pass through the polycrystalline silicon layer 3. Layers have also been proposed. In the electron source 10 'described above, the lower electrode 12, the electron passage layer, and the surface electrode 7 constitute an electron source element. However, the lower electrode and the electron passage layer made of a conductive layer on the insulating substrate An electron source in which an electron source element including a surface electrode is formed has also been proposed.

In order to emit electrons from the above-described electron source 10 ′, for example, the surface electrode 7 is provided in a state where an anode electrode 9 disposed opposite to the surface electrode 7 is provided and the space between the surface electrode 7 and the anode electrode 9 is evacuated. The DC voltage Vps is applied between the surface electrode 7 and the lower electrode 12 so that is on the high potential side with respect to the lower electrode 12, and the anode electrode 9 is on the high potential side with respect to the surface electrode 7. A DC voltage Vc is applied between the anode electrode 9 and the surface electrode 7. Here, if the DC voltage Vps is set appropriately, electrons injected from the lower electrode 12 drift through the strong electric field drift layer 6 and are emitted through the surface electrode 7 (the dashed line in FIGS. 13 and 14 indicates the surface electrode). 7 shows the flow of electrons e ⁻ emitted through 7). The electrons reaching the surface of the strong electric field drift layer 6 are considered to be hot electrons, and are easily tunneled through the surface electrode 7 and emitted into the vacuum.

  In each electron source 10 'described above, the current flowing between the surface electrode 7 and the lower electrode 12 is called a diode current Ips, and the current flowing between the anode electrode 9 and the surface electrode 7 is an emission current (emitted electron current). If referred to as Ie (see FIG. 13), the electron emission efficiency (= (Ie / Ips) × 100 [%]) increases as the ratio of the emission current Ie to the diode current Ips (= Ie / Ips) increases. . In the electron source 10 'described above, electrons can be emitted even when the DC voltage Vps applied between the surface electrode 7 and the lower electrode 12 is set to a low voltage of about 10 to 20V, and the higher the DC voltage Vps is, the higher the DC voltage Vps is. The emission current Ie increases. Here, when the DC voltage Vps applied between the surface electrode 7 and the lower electrode 12 is about 10 to 20 V, the energy of electrons emitted from the electron source 10 ′ is about 4 to 8 eV.

  The ion generator having the configuration shown in FIG. 14 has a rectangular parallelepiped case 120 ′ in which an electron source 10 ′ is accommodated, and the surface electrode 7 of the electron source 10 ′ provided above the case 120 ′ in FIG. Electrons emitted from the electron source 10 ′ are taken out of the case 120 ′ through the lattice-shaped window 121 ′ provided on the upper wall of the case 120 ′, and the window 121 ′ of the case 120 ′ is provided. The air supplied to the ion generation space B ′ between the anode electrode 9 and the anode electrode 9 is ionized. 14 indicates the flow of air supplied to the ion generation space B ′, and the arrow F12 in FIG. 14 indicates the flow of ions generated in the ion generation space B ′.

As an electron source application apparatus, an electron beam generating apparatus in which the electron beam emitted from the electron source 10 ′ is taken out through the window 121 ′ of the case 120 ′ without providing the anode electrode 9 is also conceivable.
JP 11-329213 A Japanese Patent Laid-Open No. 2000-100360 JP 2001-155622 A

  By the way, in the ion generator configured as shown in FIG. 14, the atmosphere in the case 120 ′ is air, and the electron emission characteristics (emission current Ie, electron emission efficiency, etc.) of the electron source 10 ′ are in the air. There is a problem that the amount of ions generated becomes unstable due to the influence of humidity. Also in the electron beam generator described above, the electron emission characteristics (emission current Ie, electron emission efficiency, etc.) of the electron source 10 ′ are affected by the humidity in the air, so that the amount of emitted electrons becomes unstable. There was a bug that it would end up. FIG. 15 is a graph showing an example of the measurement result of the emission current when the humidity is changed over time (the horizontal axis is the elapsed time, “I” in FIG. 15 is the humidity, and “B” is the emission current Ie). ) When the humidity exceeds 10% (10% RH), the emission current Ie starts to decrease, and when the humidity exceeds 30% (30% RH), the emission current Ie rapidly decreases.

  The present invention has been made in view of the above reasons, and an object of the present invention is to provide an electron source application apparatus that can stably generate electrons or ions without being affected by humidity in the air. is there.

  According to the first aspect of the present invention, a plurality of nanometer-order semiconductor microcrystals and an electron-passing layer formed on the surface of each semiconductor microcrystal and having a plurality of insulating films having a thickness smaller than the crystal grain size of the semiconductor microcrystal are provided at the bottom. An electron source that is provided between the electrode and the surface electrode and emits electrons through the surface electrode when a driving voltage is applied between the surface electrode and the lower electrode, with the surface electrode being a high potential side. The case is provided with a window hole at a portion facing the electron source and a gas introduction port for introducing a dry gas to be supplied to the space between the window hole and the electron source. It is characterized by becoming.

  According to the present invention, since the dry gas is supplied to the space between the window hole of the case and the electron source, the electron emission characteristics of the electron source are stabilized without being affected by the humidity in the air, Electrons or ions can be generated stably without being affected by humidity. Here, when a gas that is not ionized by an electron beam emitted from an electron source (for example, an inert gas) is adopted as a dry gas, electrons are generated as an electron source application device, and the electron source is used as a dry gas. When a gas that is ionized by an electron beam emitted from (for example, air, oxygen gas, oxygen-containing gas) is employed, the electron source application device generates ions in addition to electrons.

  According to a second aspect of the present invention, in the first aspect of the present invention, a lead electrode is provided on the inner side of the case and arranged around the window hole.

  According to the present invention, by appropriately controlling the potential of the extraction electrode, it is possible to control the amount of electrons emitted from the electron source and to control the energy of the generated electrons or ions. When the dry gas is a gas that is ionized by an electron beam, the amount of ions generated can be controlled.

  According to a third aspect of the present invention, in the first or second aspect of the present invention, a grid electrode is provided on the opposite side of the window hole from the electron source outside the case.

  According to the present invention, it is possible to control the amount of electrons emitted from the electron source and to control the energy of the generated electrons or ions by appropriately controlling the potential of the grid electrode. When the dry gas is a gas that is ionized by an electron beam, the amount of ions generated can be controlled.

  According to a fourth aspect of the present invention, in the first to third aspects of the present invention, the case has a window portion that is spaced outside the case on the opposite side of the window hole from the electron source. And a surrounding portion between the window hole projecting, and the surrounding portion is provided with another gas introduction port for introducing gas to be supplied to the space between the window portion and the window hole. It is characterized by becoming.

  According to the present invention, electrons or ions can be generated more stably.

  According to a fifth aspect of the present invention, in the first to fourth aspects of the present invention, an anode electrode is provided which is disposed outside the case and to which an acceleration voltage is applied with the surface electrode as a low potential side.

  According to the present invention, by appropriately controlling the potential of the anode electrode, the amount of electrons emitted from the electron source can be controlled, and the energy of the generated electrons or ions can be controlled. When the dry gas is a gas that is ionized by an electron beam, the amount of ions generated can be controlled.

  According to a sixth aspect of the present invention, in any of the first to fifth aspects of the present invention, the apparatus further comprises gas supply means for supplying a desired ionization target gas to a front region of the window hole outside the case.

  According to the present invention, it is possible to generate desired ions outside the case.

  A seventh aspect of the invention is characterized in that, in the fifth aspect of the invention, a workpiece is disposed on the surface of the anode electrode on the electron source side.

  According to the present invention, it is possible to cause a desired chemical action, physical action, biological action, and the like to be processed.

  The invention of claim 8 is characterized in that, in the invention of claim 3, an object to be processed is arranged on the surface of the grid electrode on the electron source side.

  According to the present invention, it is possible to cause a desired chemical action, physical action, biological action, and the like to be processed.

  A ninth aspect of the invention is characterized in that in the first to eighth aspects of the invention, the dry gas is a gas containing oxygen.

  According to the present invention, the dry gas easily becomes negative ions by the electron beam from the electron source, so that negative ions can be easily generated, and the negative gas blown out of the case through the window hole. Various ions can be generated by combining ions with gas molecules (including water molecules) in the air or transferring electrons to the other party.

  According to the first aspect of the invention, the electron emission characteristics of the electron source are stable without being affected by the humidity in the air, and electrons or ions can be stably generated without being affected by the humidity in the air. effective.

(Embodiment 1)
As shown in FIG. 1, the electron source application apparatus of the present embodiment includes an electron source 10 that emits an electron beam by field emission and a case 20 in which the electron source 10 is housed. A rectangular window hole 21 is provided at a portion opposite to the window, and a dry gas (for example, dry air, dry oxygen, inert gas, etc.) supplied to the space between the window hole 21 and the electron source 10 is introduced. A plurality (two in this embodiment) of gas inlets 22 are provided. Here, the dry gas is a low-humidity gas, preferably a gas having a humidity of 30% RH or less, and more preferably 10% RH or less. 1 indicates the flow of the dry gas introduced into the case 20 through the gas inlet 22, and the one-dot chain line arrow in FIG. 1 indicates the flow of the electrons e ⁻ emitted from the electron source 10. ing.

  As shown in FIG. 2, the electron source 10 has a metal film (for example, a tungsten film) on one surface of a rectangular plate-shaped insulating substrate (for example, an insulating glass substrate, an insulating ceramic substrate). Etc.), a strong electric field drift layer 6 is formed on the lower electrode 12, and a surface electrode 7 made of a metal thin film (for example, a gold thin film) is formed on the strong electric field drift layer 6. .

  In the electron source 10 of the present embodiment, the strong electric field drift layer 6 constitutes an electron passage layer, and the lower electrode 12, the electron passage layer, and the surface electrode 7 emit electrons into the atmosphere through the surface electrode 7. The element 10a is configured. Further, the electron source application apparatus of the present embodiment has a driving power source for applying a DC voltage (driving voltage) Vps with the surface electrode 7 as a high potential side between the surface electrode 7 and the lower electrode 12 of the electron source element 10a. I have.

  The strong electric field drift layer 6 of the electron source element 10a is formed by performing a nanocrystallization process and an oxidation process, which will be described later, and is arranged at least on the surface side of the lower electrode 12 as shown in FIG. Columnar polycrystalline silicon grains (semiconductor crystals) 51, a thin silicon oxide film 52 formed on the surface of the grains 51, and a number of nanometer-order silicon microcrystals (semiconductor microcrystals) 63 interposed between the grains 51 The silicon microcrystals 63 are considered to be composed of a large number of silicon oxide films (insulating films) 64 that are formed on the surface of each silicon microcrystal 63 and have an oxide film thickness smaller than the crystal grain size of the silicon microcrystal 63. Here, each grain 51 extends in the thickness direction of the lower electrode 12 (that is, extends in the thickness direction of the insulating substrate 11).

In order to emit electrons from the above-described electron source element 10a, driving is performed between the surface electrode 7 and the lower electrode 12 so that the surface electrode 7 is on the high potential side with respect to the lower electrode 12, as shown in FIG. When the voltage Vps is applied by the driving power source, electrons injected from the lower electrode 12 into the strong electric field drift layer 6 drift through the strong electric field drift layer 6 and are emitted through the surface electrode 7 (the one-dot chain line in FIG. The flow of electrons e ⁻ emitted through the electrode 7 is shown). Here, electrons reaching the surface of the strong electric field drift layer 6 are considered to be hot electrons, and easily tunnel through the surface electrode 7 and are emitted into the atmosphere. In the electron source 10 in the present embodiment, electrons are emitted even when the driving voltage Vps applied with the surface electrode 7 between the surface electrode 7 and the lower electrode 12 on the high potential side is set to a low voltage of about 10 to 20V. As the drive voltage Vps increases, the emission current increases and the energy of the emitted electrons increases. Here, the drive voltage Vps applied to the electron source 10 may be a constant DC voltage or a pulsed voltage. When the drive voltage Vps is a pulse voltage, a reverse bias voltage may be applied when the drive voltage Vps is not applied. Further, the acceleration voltage Vc applied between the anode electrode 9 and the surface electrode 7 may be a DC voltage or a pulse voltage together with the drive voltage Vps.

The basic configuration of the electron source element 10a in this embodiment is well known, and it is considered that electron emission occurs in the following model. That is, by applying a voltage between the surface electrode 7 and the lower electrode 12 with the surface electrode 7 set to the high potential side, electrons e ⁻ are injected from the lower electrode 12 into the strong electric field drift layer 6. On the other hand, since most of the electric field applied to the strong electric field drift layer 6 is applied to the silicon oxide film 64, the injected electrons e ⁻ are accelerated by the strong electric field applied to the silicon oxide film 64, and the strong electric field drift layer 6. 3 drifts toward the surface in the direction of the arrow in FIG. 3 (upward in FIG. 3), and the surface electrode 7 is tunneled and emitted. Thus, in the strong electric field drift layer 6, electrons injected from the lower electrode 12 are almost scattered by the silicon microcrystal 63, are accelerated by the electric field applied to the silicon oxide film 64, and drift through the surface electrode 7. Since the heat generated in the strong electric field drift layer 6 is dissipated through the grains 51, no popping phenomenon occurs during electron emission, and electrons can be stably emitted.

  An example of a method for forming the above-described strong electric field drift layer 6 will be described.

In forming the strong electric field drift layer 6, first, a non-doped polycrystalline silicon layer is formed on the lower electrode 12 formed on the insulating substrate 11 by, for example, the LPCVD method, and then the above-described nanocrystallization process is performed. Thus, a composite nanocrystal layer (hereinafter referred to as a first composite nanocrystal layer) in which a large number of grains 51 of polycrystalline silicon (see FIG. 3) and a large number of silicon microcrystals 63 (see FIG. 3) are mixed is formed. To do. Here, in the nanocrystallization process, for example, an electrolytic solution made of a mixed solution in which a 55 wt% aqueous solution of hydrogen fluoride and ethanol are mixed at approximately 1: 1 is used, and the lower electrode 12 is used as an anode, and a large amount in the electrolytic solution. A constant current (for example, between the anode and the cathode from the power source) while a cathode made of a platinum electrode is disposed opposite to the crystalline silicon layer and light is irradiated to the main surface of the polycrystalline silicon layer by a light source made of a 500 W tungsten lamp. Then, a first composite nanocrystal layer including polycrystalline silicon grains 51 and silicon microcrystals 63 is formed by flowing a current density of 12 mA / cm ² for a predetermined time (for example, 10 seconds).

After the nanocrystallization process is completed, the above-described oxidation process is performed to electrochemically oxidize the first composite nanocrystal layer, thereby forming a composite nanocrystal layer (hereinafter referred to as a second nanocrystal layer) having a configuration shown in FIG. The strong electric field drift layer 6 is formed. In the oxidation process, for example, an electrolytic solution made of a solution obtained by dissolving 0.04 mol / l potassium nitrate in an organic solvent made of ethylene glycol is used, the lower electrode 12 is used as an anode, and the first composite in the electrolytic solution is used. A cathode made of a platinum electrode is placed opposite to the nanocrystal layer, the lower electrode 12 is used as an anode, and a constant current (for example, a current density of 0.1 mA / cm ² ) is passed between the anode and the cathode from the power source. By electrochemically oxidizing the first composite nanocrystal layer until the voltage between the anode and the cathode is increased by 20V, the above-described grain 51, silicon microcrystal 63, and silicon oxide films 52 and 64 are included. A strong electric field drift layer 6 made of the second composite nanocrystal layer is formed. In the present embodiment, in the first composite nanocrystal layer formed by performing the above-described nanocrystallization process, the regions other than the grains 51 and the silicon microcrystals 63 are amorphous regions made of amorphous silicon. In the strong electric field drift layer 6, regions other than the grains 51, silicon microcrystals 63, and the silicon oxide films 52 and 64 are amorphous regions 65 made of amorphous silicon or partially oxidized amorphous silicon. Depending on the conditions, the amorphous region 65 becomes a hole, and the first composite nanocrystal layer in such a case can be regarded as a porous polycrystalline silicon layer.

  In the above-described strong electric field drift layer 6, the silicon oxide film 64 constitutes an insulating film and an oxidation process is employed for forming the insulating film, but a nitriding process or an oxynitriding process is employed instead of the oxidation process. Alternatively, when the nitriding process is adopted, each of the silicon oxide films 52 and 64 becomes a silicon nitride film, and when the oxynitriding process is adopted, each of the silicon oxide films 52 and 64 is silicon oxynitride. Become a film.

  The case 20 is formed in a rectangular parallelepiped shape. If the vertical direction and the left-right direction are defined using FIG. 1A, the electron source 10 is disposed on the surface facing the upper wall of the lower wall, and the case 20 A window hole 21 is provided at a portion facing the electron source 10. In addition, the case 20 is provided with a gas introduction port 22 at the distal end surface of a cylindrical introduction portion 20a that protrudes laterally from the left and right side walls, and the cross-sectional area of each flow passage of each introduction portion 20a is the case 20. Is smaller than the cross-sectional area of the flow path of the portion (case body) between the two introduction portions 20a. In addition, the cross-sectional area of the flow path of each introducing | transducing part 20a may be the same as the cross-sectional area of the flow path of the said case main body, and may be larger than the cross-sectional area of the flow path of the said case main body.

  Therefore, in the electron source application apparatus according to the present embodiment, the dry gas is supplied to the space between the window hole 21 of the case 20 and the electron source 10, so that the electron emission characteristic of the electron source 10 is the humidity in the air. It is possible to generate electrons or ions stably without being affected by humidity in the air. Here, when a gas that is not ionized by an electron beam emitted from the electron source 10 (for example, an inert gas) is employed as the dry gas supplied into the case 20, the electron source application device generates electrons. When a gas generator ionized by the action of the electron beam emitted from the electron source 10 as a dry gas (for example, air, oxygen gas, gas containing oxygen, etc.) is adopted as the dry gas. The application apparatus constitutes an ion generator that generates ions. For example, when it is desired to generate negative ions, a gas containing an element having a positive electron affinity or a gas containing an element having a high electron affinity (for example, oxygen gas) is used as a dry gas from the outside of the case 20. What is necessary is just to introduce | transduce into case 20 through the gas inlet 22, and when oxygen gas is employ | adopted as dry gas, a negative ion can be produced | generated easily and the negative ion which blows out of the case 20 through the window hole 21 is generated. Various ions are generated by being associated with gas molecules (including water molecules) in the air or by transferring electrons to the other party. As the flow rate of the dry gas introduced into the case 20 through the gas inlet 22 increases, the amount of ions generated increases and the amount of ions generated stabilizes.

  In the present embodiment, each introduction portion 20a is formed in a cylindrical shape, but is not limited to a cylindrical shape, and may be a rectangular tube shape, for example. Further, the number of the gas inlets 22 is not limited to two, but may be one or three or more, and the gas inlets 22 are formed over the entire circumference of the outer peripheral surface of the case 20. May be. For example, when four gas introduction ports 22 are provided, the introduction part 20 a may be provided on each of the four side surfaces of the case 20. The shape of the gas inlet 22 is not limited to a circular shape, and may be a rectangular shape, for example.

(Embodiment 2)
The basic configuration of the electron source application apparatus according to the present embodiment is substantially the same as that of the first embodiment. As shown in FIG. 4, as shown in FIG. 4, an extraction electrode 31 disposed on the periphery of the window hole 21 inside the case 20, and the case 20 is different from the first embodiment in that a flat plate-like anode electrode 9 to which an acceleration voltage is applied with the surface electrode 7 as a low potential side is provided between the surface electrode 7 and the surface electrode 7. The description is omitted because it is the same as. Here, the shape of the extraction electrode 31 is a rectangular frame shape that surrounds the rectangular window hole 21 over the entire circumference inside the case 20. In short, the extraction electrode 31 has a rectangular frame shape in a plane parallel to the surface of the surface electrode 7 (see FIG. 2) of the electron source 10.

  Therefore, in the electron source application apparatus of the present embodiment, the amount of electrons emitted from the electron source 10 is controlled or generated in the case 20 by appropriately controlling the potentials of the extraction electrode 31 and the anode electrode 9, respectively. It becomes possible to control the energy of electrons or ions. Further, when the dry gas supplied into the case 20 is a gas that is ionized by an electron beam, the amount of ions generated can be controlled. Here, the potential of the extraction electrode 31 is preferably set so as to be higher than the surface electrode 7 of the electron source 10. Further, the potential of the anode electrode 9 is preferably set to be higher than the potential of the extraction electrode 31. Further, shortening the distance between the extraction electrode 31 and the electron source 10 has an advantage that the potential of the extraction electrode 31 can be reduced and the power consumption can be reduced. It is possible to generate not only negative ions but also positive ions. When positive ions are generated, the ionization energy (ionization energy, usually several tens of hours) of the dry gas is formed between the anode electrode 9 and the surface electrode 9. What is necessary is just to make it apply the voltage (usually dozens of volt-several MV) which gives more energy than eV.

  By the way, in this embodiment, the shape of the extraction electrode 31 is a rectangular frame shape that surrounds the rectangular window hole 21 around the entire circumference inside the case 20, but the shape of the extraction electrode 31 is not particularly limited. Instead, for example, as shown in FIG. 5, strip-shaped extraction electrodes 31 may be provided on both sides of the rectangular window hole 21. The relative positional relationship between the extraction electrode 31 and the electron source 10 may be set as appropriate. For example, the planar size of the electron source 10 is made larger than the size of the window hole 21 as shown in FIG. Thus, the extraction electrode 31 may be disposed at a portion facing the peripheral portion of the electron source 10 in the thickness direction of the electron source 10, or the planar size of the electron source 10 may be set to the size of the window hole 21 as shown in FIG. The extraction electrode 31 may be arranged in an oblique direction with respect to the electron source 10 so as to be smaller than the size, or the electron source 10 is placed at a position overlapping in the thickness direction of the extraction electrode 31 as shown in FIG. It may be arranged.

  Further, in the electron source application apparatus of the present embodiment, the extraction electrode 31 and the anode electrode 9 are added as compared with the configuration of the first embodiment, but only one of the extraction electrode 31 and the anode electrode 9 is added. The configuration described above may be adopted. The shape of the anode electrode 9 is not limited to a plate shape, and may be changed as appropriate, such as a mesh shape or a line shape.

(Embodiment 3)
The basic configuration of the electron source application apparatus of the present embodiment is substantially the same as that of the first embodiment, and as shown in FIG. 7, the mesh disposed on the opposite side of the window hole 21 from the electron source 10 as shown in FIG. The other points are the same as those of the first embodiment, and the illustration and description are omitted. The grid electrode 32 may be formed of a metal or a conductor other than metal.

  Therefore, in the electron source application apparatus of this embodiment, the amount of electrons emitted from the electron source 10 is controlled by appropriately controlling the potential of the grid electrode 32, or the energy of electrons or ions generated in the case 20 is controlled. In addition, when the dry gas supplied in the case 20 is a gas that is easily ionized by the electron beam emitted from the electron source 10, the amount of ions generated can be controlled. In addition, since the grid electrode 32 described above is provided, the influence on the electron source 10 from an external environment such as dust or dirt can be suppressed. The potential of the grid electrode 32 may be set to be a high potential or a low potential with respect to the surface electrode 7 (see FIG. 2) of the electron source 10, or may be a ground potential. Further, the grid electrode 32 may be in an electrically floating state. Further, the distance d between the grid electrode 32 and the upper surface of the case 20 may be set as appropriate, and the distance d may be zero. Moreover, the mesh roughness of the mesh-like grid electrode 32 is not particularly limited, but from the viewpoint of increasing the amount of generated electrons and ions, it is preferable that the roughness is coarse. Further, the shape of the grid electrode 32 is not limited to a mesh shape, and may be any shape as long as it has a portion through which ions pass. May be a concentrically arranged shape, or a plurality of linear wires arranged in parallel.

(Embodiment 4)
The basic configuration of the electron source application apparatus of the present embodiment is substantially the same as that of the third embodiment. As shown in FIG. 8, an enclosure 24 that surrounds the space between the grid electrode 32 and the window hole 21 is formed from the case 20. Two gas inlets 25 for introducing a gas (for example, a gas containing dry gas or water vapor) to be supplied to the space between the grid electrode 32 and the window hole 21 are provided in the surrounding portion 24. The other points are the same as in the third embodiment, and the illustration and description are omitted. Here, the surrounding part 24 has a window part that is spaced apart from the electron source 10 in the window hole 21 outside the case 20, and a grid electrode 32 is provided in the window part. Further, the gas introduction ports 25 are formed on the front end surface of the cylindrical introduction portion 24a projecting sideways from the left and right side walls of the surrounding portion 24 in FIG. 8, but the number of the gas introduction ports 25 is the same as that of the first embodiment. Similarly to the number of gas inlets 22 described above, there is no particular limitation. Note that an arrow F2 in FIG. 8 indicates the flow of gas introduced into the enclosure 24 through the gas inlet 25.

  Thus, the electron source application apparatus of the present embodiment can generate electrons or ions more stably than the electron source application apparatus of the third embodiment. The gas introduced through the gas inlet 25 may be the same gas as the dry gas introduced through the gas inlet 22 or may be a different gas. In the case of different gases, it is possible to generate ions of the gas introduced through the gas introduction port 25, so that there is an advantage that a plurality of or different types of ions can be generated. In the configuration of this embodiment, the grid electrode 32 is not necessarily provided, and the extraction electrode 31 described in the second embodiment may be provided.

(Embodiment 5)
The basic configuration of the electron source application apparatus of the present embodiment is substantially the same as that of the first embodiment. As shown in FIG. 9, the electron source application apparatus is opposed to the surface electrode 7 of the electron source 10 (see FIG. 2). A mesh-like anode electrode 9 to which an acceleration voltage is applied with the surface electrode 7 positioned between the anode electrode 9 and the surface electrode 7 is disposed between the anode electrode 9 and the surface electrode 7. A difference is that an acceleration power source (not shown) that applies a DC voltage (acceleration voltage) Vc is provided on the high potential side (that is, the surface electrode 7 is on the low potential side), and the other configuration is the same as that of the first embodiment. Therefore, illustration and description are omitted.

  Thus, in the electron source application apparatus of the present embodiment, the amount of electrons emitted from the electron source 10 is controlled by appropriately controlling the potential of the anode electrode 9, and the energy of electrons or ions generated in the case 20 is controlled. Can be controlled. In addition, when the dry gas supplied into the case 20 is a gas ionized by an electron beam emitted from the electron source 10 (for example, oxygen gas), the amount of generated ions can be controlled ( The arrow F3 in FIG. 9 shows the flow of generated ions). Note that the mesh roughness of the mesh-like anode electrode 9 is not particularly limited, but from the viewpoint of increasing the amount of generated electrons and ions, it is preferable that the roughness is coarse. Further, the shape of the anode electrode 9 is not limited to the mesh shape, and may be any shape as long as it has a portion through which ions pass. For example, the anode electrode 9 may have a plate shape having a large number of holes or a plurality of annular wires having different inner diameters. May be a concentrically arranged shape, or a plurality of linear wires arranged in parallel. Further, the acceleration voltage Vc applied between the anode electrode 9 and the surface electrode 7 may be a DC voltage or a pulse voltage together with the drive voltage Vps.

(Embodiment 6)
The basic configuration of the electron source application apparatus of the present embodiment is substantially the same as that of the first embodiment. As shown in FIG. 10, the electron source application apparatus is disposed on the outside of the case 20 so as to face the surface electrode 7 and between the surface electrode 7. The difference is that the rectangular frame-shaped anode electrode 9 to which the acceleration voltage Vc is applied with the surface electrode 7 as the low potential side is disposed, and the mesh-shaped extraction electrode 31 is disposed inside the case 20. Since other configurations are the same as those of the first embodiment, illustration and description thereof are omitted.

  Therefore, in the electron source application apparatus of the present embodiment, the amount of electrons emitted from the electron source 10 is controlled or generated in the case 20 by appropriately controlling the potentials of the extraction electrode 31 and the anode electrode 9, respectively. It becomes possible to control the energy of electrons or ions. In addition, when the dry gas supplied into the case 20 is a gas that is ionized by an electron beam, the amount of ions generated can be controlled. Here, the potential of the extraction electrode 31 is preferably set so as to be higher than the surface electrode 7 of the electron source 10. Further, from the viewpoint of increasing the amount of electrons and the amount of ions when the potential of the anode electrode 9 is set to be higher than the potential of the extraction electrode 31, when electrons and negative ions are generated. preferable. Further, shortening the distance between the extraction electrode 31 and the electron source 10 has an advantage that the potential of the extraction electrode 31 can be reduced and the power consumption can be reduced. The shape of the anode electrode 9 is not limited to a rectangular frame shape, and may be an annular shape, for example.

(Embodiment 7)
The basic configuration of the electron source application apparatus of the present embodiment is substantially the same as that of the second embodiment. As shown in FIG. 11, the space between the window hole 21 of the case 20 and the anode electrode 9 (that is, the case 20 It is different in that it includes a water supply means 40 for supplying, for example, water vapor, water vapor containing medicinal effects as a desired ionization target gas from the side to the front region of the window hole 21 on the outside), Since other configurations are the same as those of the second embodiment, illustration and description thereof are omitted. The two-dot chain line in FIG. 11 schematically shows the flow of gas supplied from the gas supply means 40. In the present embodiment, the moisture supply means 40 constitutes a gas supply means.

  Therefore, in the electron source application apparatus of the present embodiment, desired ions can be generated outside the case 20. In short, in the electron source application apparatus of the present embodiment, it is possible to generate desired ions outside the case 20, which are different from the ions generated when the electron beam acts on the dry gas in the case 20. In addition, of course, you may provide the gas supply means 40 in this embodiment in other Embodiment 1-6.

(Embodiment 8)
The basic configuration of the electron source application apparatus of the present embodiment is substantially the same as that of the second embodiment. As shown in FIG. 12, the surface of the anode electrode 9 on the side of the electron source 10 (the surface facing the electron source 10) The difference is that a workpiece 33 made of a catalyst activated by irradiation of electrons generated in the case 20 is arranged, and the other configurations are the same as those of the second embodiment, and therefore illustration and description thereof are omitted. In addition, the to-be-processed object 33 is not limited to a catalyst, What is necessary is just a substance (for example, water etc.) which a chemical effect | action, a physical effect | action, a biological effect | action etc. produce by irradiation of an electron or ion.

  Therefore, in the electron source application apparatus according to the present embodiment, a chemical action, a physical action, a biological action, or the like is generated outside the case 20 by irradiating the workpiece 33 with electrons or ions. It becomes possible. In addition, you may provide the to-be-processed object 33 in the anode electrode 9 and the grid electrode 31 in other embodiment.

  By the way, in each of the above embodiments, if a structure in which a plurality of cases 20 containing at least the electron source 10 are stacked is adopted, the amount of electrons or ions generated is increased when the plurality of electron sources 10 are driven simultaneously. Can do. In addition, since the plurality of electron sources 10 can be appropriately driven by sequentially driving the plurality of electron sources 10, the generated electrons or ions can be stably generated over a long period of time.

  In the electron source 10 of each of the embodiments described above, the lower electrode 12 is formed on the one surface side of the insulating substrate 11, but a semiconductor substrate such as a silicon substrate is used instead of the insulating substrate 11. A lower electrode may be configured by a conductive layer (for example, an ohmic electrode) laminated on the back side of the semiconductor substrate. The electron source 10 in each of the above embodiments is an electron source that emits electrons by a ballistic electron emission phenomenon, and is called a ballistic electron surface-emitting device (BSD). The electron source 10 is not limited to BSD, and may be any electron source that can emit electrons at atmospheric pressure.

The electron source application apparatus of Embodiment 1 is shown, (a) is a schematic sectional drawing, (b) is a schematic plan view. It is operation | movement explanatory drawing of the electron source element in the same as the above. It is principal part explanatory drawing of the electron source element same as the above. The electron source application apparatus of Embodiment 2 is shown, (a) is a schematic sectional drawing, (b) is a principal part schematic plan view. It is a bottom view of the other structural example of the principal part same as the above. It is explanatory drawing of another structural example of the principal part same as the above. It is a schematic sectional drawing of the electron source application apparatus of Embodiment 3. It is a schematic sectional drawing of the electron source application apparatus of Embodiment 4. The electron source application apparatus of Embodiment 5 is shown, (a) is a schematic sectional drawing, (b) is a schematic plan view. The electron source application apparatus of Embodiment 6 is shown, (a) is a schematic sectional drawing, (b) is a schematic plan view. It is a schematic block diagram of the electron source application apparatus of Embodiment 7. It is a schematic sectional drawing of the electron source application apparatus of Embodiment 8. It is operation | movement explanatory drawing of the electron source in a prior art example. It is a schematic block diagram of the ion generator which shows a prior art example. It is a graph which shows the humidity dependence of the emission current in the electron source of a prior art example.

Explanation of symbols

10 electron source 20 case 21 window hole 22 gas inlet

Claims (9)

  An electron source capable of emitting electrons at atmospheric pressure and a case in which the electron source is stored are provided. The case is provided with a window hole at a portion facing the electron source and between the window hole and the electron source. An electron source application apparatus comprising a gas inlet for introducing a dry gas to be supplied to the space.   The electron source application apparatus according to claim 1, further comprising an extraction electrode disposed on a peripheral portion of the window hole inside the case.   The electron source application apparatus according to claim 1, further comprising a grid electrode disposed on an opposite side of the window hole from the electron source outside the case.   The case has a window portion projecting from the outside of the case and surrounding the space between the window portion and the window hole having a window portion that is spaced apart from the electron source in the window hole. The other gas introduction port which introduces the gas supplied to the space between a window part and the said window hole is provided in the enclosure part, The Claim 1 thru | or 3 characterized by the above-mentioned. Electron source application equipment.   5. The electron source application apparatus according to claim 1, further comprising an anode electrode that is disposed outside the case and to which an acceleration voltage is applied with the electron source at a low potential side.   6. The electron source application apparatus according to claim 1, further comprising gas supply means for supplying a desired ionization target gas to an area in front of the window hole outside the case.   6. The electron source application apparatus according to claim 5, wherein a workpiece is disposed on a surface of the anode electrode on the electron source side.   4. The electron source application apparatus according to claim 3, wherein an object to be processed is arranged on a surface of the grid electrode on the electron source side.   9. The electron source application apparatus according to claim 1, wherein the dry gas is a gas containing oxygen.

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