JP5336691B2 - Plasma generator, surface treatment apparatus, light source, plasma generation method, surface treatment method, and light irradiation method - Google Patents

Description

  The present invention relates to a plasma generation apparatus, a surface treatment apparatus, a light source, a plasma generation method, a surface treatment method, and a light irradiation method using an electrode including a conductive member covered with an insulator or a dielectric.

  2. Description of the Related Art Conventionally, a method using plasma to perform cleaning, etching, film formation, and the like is known.

  In Patent Document 1, in order to perform stable discharge in the atmosphere without using helium gas, a reaction tube that supplies a reaction gas, and first and second elements that are disposed opposite to each other across the reaction tube and act on the reaction gas. There is disclosed a plasma processing apparatus that supplies a high frequency power to first and second electrodes to excite a reactive gas and processes a substrate to be processed with generated plasma.

  In Patent Document 2, in order to generate a uniform discharge plasma under a pressure in the vicinity of atmospheric pressure regardless of the gas atmosphere at the time of processing, a solid dielectric is disposed on at least one facing surface of the counter electrode, A technique for applying a pulsed electric field in between is disclosed.

The technique disclosed in Patent Document 1 is a technique in which a reaction gas flowing in a reaction tube is converted into plasma, and the plasma is injected from the reaction tube to an object to be processed. Surface treatment is performed on an object to be treated placed on a two-electrode plate, and both are surface treatment techniques based on a relatively large apparatus.
JP 2002-184759 A JP-A-10-154598

  However, the above-described conventional technique has a large apparatus, and plasma is generated only in a limited space in the apparatus. In these apparatuses, the space in which plasma is generated is wide, and it is difficult to generate minute plasma. Therefore, with these techniques, a minute part of a certain member cannot be processed with plasma or sterilized.

  Regarding microscopic plasmas, the Stoffel group at the Eindhoven University of Technology in the Netherlands has reported plasma needles. This is a method that uses RF plasma, concentrically arranges ground electrodes around the center needle electrode, and generates plasma with a diameter of about 0.5 mm at the tip of the needle electrode, but matching is difficult. There are problems that it is very difficult to generate plasma, it is difficult to generate plasma with a gas other than helium, and plasma generation of less than 0.5 mm has not been confirmed.

  At present, there is a demand for smaller, more precise, cleaner, etc. in various fields, and various treatments using minute plasma have been demanded. The apparatus and method to be generated were not excluded from the Stoffel group described above. The Stoffel group also has the above problems.

  This invention is made | formed in view of this point, The place made into the objective is to provide the plasma generator and plasma generation method which generate | occur | produce a minute plasma by a simple method.

  In order to solve the above problems, a first plasma generator of the present invention includes a first electrode provided with a conductive member covered with an insulator or a dielectric, and an AC voltage or a voltage applied to the first electrode. And a part of the insulator or dielectric coating of the first electrode is configured to have a dielectric constant higher than a part other than the part, Plasma is generated around a part. Here, a part of the insulator or dielectric coating of the first electrode is configured to have a dielectric constant higher than that of the part other than the part. For example, a material having a dielectric constant higher than that of the other part is used only for the part. In the first electrode, since a part of the coating has a higher dielectric constant than the other part, the electric field concentrates on this part, and plasma is generated in this part. An insulator or a dielectric may be interposed between the second electrode and the first electrode.

  A second plasma generation apparatus of the present invention includes a first electrode including a conductive member covered with an insulator or a dielectric, and a power source that applies an AC voltage or a pulse voltage to the first electrode. The first electrode has a portion where the conductive member is exposed from the insulating or dielectric coating, and generates plasma around the exposed portion. In the first electrode, since the conductive member is partially exposed from the coating, the electric field is concentrated on this portion, and plasma is generated in this portion.

  A third plasma generating apparatus of the present invention includes a first electrode including a conductive member covered with an insulator or a dielectric, and a power source that applies an AC voltage or a pulse voltage to the first electrode. The conductive member has protrusions or corners, and generates plasma around the protrusions or corners. In the first electrode, since the conductive member has a protrusion or a corner, the electric field concentrates on this portion, and plasma is generated in this portion.

  A surface treatment apparatus according to the present invention includes the above-described plasma generation apparatus according to the present invention, which performs surface treatment of a workpiece with the plasma. Surface treatment refers to any physical or chemical treatment performed on the surface of the object to be treated, such as etching, treatment for bonding a molecule having a functional group to the object to be treated, heat treatment, treatment for colliding electrons, or film formation. is there.

  The light source of the present invention includes the above-described plasma generator of the present invention using ultraviolet light or visible light generated from the plasma.

  A first plasma generation method of the present invention includes a conductive member covered with an insulator or a dielectric, and a dielectric constant of a part of the insulator or the dielectric is higher than that of a part other than the part. A step of installing a first electrode configured to be high at a predetermined position, and plasma generation for generating plasma around the part by applying an AC voltage or a pulse voltage to the first electrode Process. In the first electrode, since a part of the coating has a higher dielectric constant than the other part, the electric field concentrates on this part, and plasma is generated in this part.

  The second plasma generation method of the present invention includes a conductive member covered with an insulator or a dielectric, and the conductive member has a portion exposed from the coating of the insulator or dielectric. A step of placing the first electrode at a predetermined position, and a plasma generation step of applying an alternating voltage or a pulse voltage to the first electrode to generate plasma around the exposed portion. In the first electrode, since there is a portion where the conductive member is exposed from the coating, the electric field concentrates on this portion, and plasma is generated in this portion.

  The third plasma generation method of the present invention includes a step of installing a first electrode, which is covered with an insulator or a dielectric, and includes a conductive member having a protrusion or a corner, at a predetermined position; A plasma generation step of applying an alternating voltage or a pulse voltage to the first electrode to generate plasma around the protrusions or corners. In the first electrode, since the conductive member has a protrusion or a corner, the electric field concentrates on this portion, and plasma is generated in this portion.

  According to a fourth plasma generation method of the present invention, a step of installing a first electrode including a linear conductive member covered with an insulator or a dielectric at a predetermined position; A plasma generation step of generating plasma around the tip of the first electrode by applying an alternating voltage or a pulse voltage. In the first electrode, even if the coating is uniform, the electric field is concentrated on the tip portion, and plasma is generated in this portion.

  In a preferred embodiment, the apparatus further includes a second electrode connected to the power source and applied with the AC voltage or the pulse voltage between the first electrode and the first electrode.

  In a preferred embodiment, the apparatus further includes a ground electrode connected to the power source and applied with the AC voltage or pulse voltage between the first electrode and the first electrode.

  In a preferred embodiment, the apparatus further includes a gas introduction part that introduces a predetermined gas around at least the part. The part of the periphery includes a region where the part is on the outer surface side and plasma is generated.

  In a preferred embodiment, the apparatus further includes a gas introduction part for introducing a predetermined gas around at least the exposed portion. The periphery of the exposed portion includes a region where plasma is generated on the outer surface side of the exposed portion.

  In a preferred embodiment, the apparatus further includes a gas introduction part that introduces a predetermined gas at least around the protrusions or corners. The periphery of the protrusion or corner includes a region where plasma is generated on the outer surface side of the protrusion or corner.

  In the surface treatment method of the present invention, the surface treatment of the workpiece is performed by the plasma generated by the above plasma generation method.

  The light irradiation method of the present invention uses ultraviolet light or visible light generated from the plasma generated by the above plasma generation method.

  A fourth plasma generator of the present invention includes a first electrode including a conductive member covered with an insulator or a dielectric, a second electrode having a protrusion or a corner, and the first electrode. And a power source for applying an AC voltage or a pulse voltage between the first electrode and the second electrode, and a discharge is generated in a portion of the first electrode closest to a tip or a corner of the protrusion, and the periphery of the portion To generate plasma.

  According to a fifth plasma generation method of the present invention, a step of installing a first electrode including a conductive member covered with an insulator or a dielectric, and a second electrode having a protrusion or a corner are predetermined. And applying an alternating voltage or a pulse voltage between the first electrode and the second electrode, and being closest to the tip or the corner of the protrusion of the first electrode. A step of increasing the electric field strength between the portion and the second electrode to be larger than other regions, and generating plasma in the vicinity of a portion of the first electrode closest to a tip or a corner of the protrusion, Plasma generating step. The second electrode having the protrusion includes an acicular electrode.

  Since the dielectric constant of a part of the coating of the first electrode is increased or the conductive member is partially exposed so that the electric field concentrates on the part, the size of the part By adjusting the above, it is possible to easily generate a microplasma having an arbitrary size at an arbitrary location.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following drawings, components having substantially the same function are denoted by the same reference numerals for the sake of brevity.

(Embodiment 1)
The plasma generator of Embodiment 1 is shown in FIG. This plasma generator is an apparatus that generates plasma around a part of the generation point 10 of the first electrode 30. This apparatus includes a first electrode 30, a second electrode 20, and a power supply 40 that applies an AC voltage or a pulse voltage between the first electrode 30 and the second electrode 20.

  As shown in FIG. 2, the first electrode 30 has a structure in which a coating 32 made of an insulator or a dielectric is applied to the surface of the conductive member 31. The conductive member 31 may be any material as long as it has conductivity such as metal, carbon, and organic conductive material. In this embodiment, a copper wire is used.

  Examples of the insulator constituting the coating 32 include a fluorine resin such as PFA, PTFE, and FEP, an electrically insulating polymer such as polyimide resin, or an electrically insulating inorganic material such as diamond-like carbon (DLC). . Moreover, as a dielectric material which comprises the coating | cover 32, substances with high dielectric constant, such as barium titanate, can be mentioned. In this embodiment, the coating 32 is formed of Teflon (registered trademark) which is a fluororesin.

  In the present embodiment, the generation point 10 is a portion where the thickness of the coating 32 is thinner than other portions as shown in FIG. This portion can be formed by mechanically removing the coating 32 or processing with a laser or the like. In this embodiment, a circular recess having a diameter of 50 μm formed by laser processing is used.

  Here, assuming that the conductive member 31 is not exposed at all in the entire first electrode 30 without any coating 32, the discharge concentrates on a specific portion of the conductive member 31, and the dielectric breakdown is caused by the spark discharge. There is a very high possibility that it will be.

  In addition, when an alternating voltage or a pulse voltage is applied between the first electrode 30 and the second electrode 20 to generate plasma around the first electrode 30, the temperature of the first electrode 30 increases. It is preferable that the conductive member 31 and the coating 32 have high heat resistance, specifically, those that do not deteriorate when held at 50 ° C. for 1 hour. From the viewpoint of heat resistance, the conductive member 31 is preferably made of metal, carbon or the like, and the coating 32 is preferably made of fluorine resin, polyimide resin, DLC, barium titanate or the like.

  The second electrode 20 is connected to the power supply 40 by a connection line 60. The shape and material of the second electrode 20 are not particularly limited. For example, the shape of the second electrode 20 may be any shape such as a flat plate shape, a cylindrical shape, a mesh shape, or a wire shape. The material of the second electrode 20 may be any material as long as it is conductive, such as metal, carbon, or an organic conductive material. Furthermore, the surface of the second electrode 20 may be covered with an insulator. In the present embodiment, a metal plate covered with an insulating resin is used as the second electrode 20.

  The power source 40 applies an AC voltage or a pulse voltage. The shape, material, and length of the first electrode 30, such as the distance between the generation point 10 and the second electrode 20, the temperature of the atmosphere, and the generation point 10 Whether the plasma is generated or not, and the intensity of the plasma are greatly influenced by the size of the coating, the thickness of the coating 32 of the portion, and the like. Also, what is important for the generation of the plasma is not the applied voltage but the surrounding of the generation point 10. Since it is electric field strength, the frequency and magnitude of the AC voltage or pulse voltage are not particularly limited. As shown in FIG. 4, the pulse voltage is preferably a pulse of changing polarity (from + to-, or from-to +), or a pulse that rises from 0 V. When the pulse voltage is supplied continuously in time, the plasma continues. This is preferable. The pulse voltage continuously supplied in this way can be said to be a square wave AC voltage.

Although the frequency and voltage of the power supply 40 are not particularly limited, the frequency is preferably 0.1 Hz to 100 MHz for practical use as a power supply device, and 50 Hz to 1 MHz is preferable in consideration of the ease of plasma generation. The voltage is preferably 1 V to 500 kV because plasma is easily generated, and 1 V to 100 kV is preferable from the viewpoint of easy handling of the apparatus. Alternatively, the electric field strength in the vicinity of the first electrode 30 when an AC voltage or a pulse voltage is applied to the first electrode 30 by the power source 40 is preferably 10 ⁴ V / m or more and 10 ¹⁰ V / m or less.

  Next, a method for generating plasma using the plasma generator of this embodiment will be described.

  First, the first electrode 30 is installed at a predetermined position. The predetermined position is a position where the generation point 10 is arranged in the vicinity of a minute place where plasma processing is to be performed, for example. The first electrode 30 is connected to the power source 40.

  Then, the second electrode 20 is disposed in the vicinity of the first electrode 30. The second electrode 20 is preferably arranged in the vicinity of the generation point 10. The second electrode 20 is connected to the power source 40.

  Next, an alternating voltage or a pulse voltage is applied between the first electrode 30 and the second electrode 20. Then, the electric field concentrates at the generation point 10 and plasma is generated.

  The generated plasma is applied to the surface of the workpiece to perform surface treatment, sterilization, or light generated from the plasma is used as a light source. Examples of the surface treatment with plasma include etching and hydrophilic treatment. In the case of using plasma as a light source, an example in which only a specific spot of an ultraviolet curable resin is cured using ultraviolet light generated from the plasma can be given as an example.

  As described so far, in this embodiment, a part of the coating 32 of the first electrode 30 provided with the conductive member 31 covered with an insulator or a dielectric is made thinner than the other parts to provide insulation. Since the plasma is generated around the generation point 10 by applying an AC voltage or a pulse voltage between the first electrode 30 and the second electrode 20 at a low level, a very small plasma that could not be achieved by the conventional apparatus Can be easily generated. The plasma generated in this way can be used for surface treatment or sterilization of a minute region, or as a light source or the like. Since the generated plasma is minute, it generates less heat and can perform plasma processing at a low temperature. In addition, the plasma generator of this embodiment has a very simple structure, and can reduce the manufacturing cost. Further, plasma generation can be easily performed even by an unskilled person. The size of the plasma can also be set to an arbitrary size by changing the size of the generation point 10. Note that the degree of plasma generation can be determined by the intensity of light emission.

  In this embodiment, the generation point 10 is formed by thinning the coating 32. However, the coating material of this portion is made to have a higher dielectric constant than the surrounding coating material, or the coating 32 is cut. Thus, the generation point 10 may be formed. Further, when the first electrode 30 is linear as in the present embodiment, the electric field tends to concentrate on the tip portion, and even if the second electrode 20 is far away from the tip portion, plasma is generated at the tip portion. Therefore, when the generation point 10 is formed in addition to the tip portion, it is preferable to increase the coating thickness of the tip portion or cover only the tip portion with a material having a low dielectric constant.

(Embodiment 2)
As shown in FIG. 5, the plasma generator according to the second embodiment is the same as the plasma generator according to the first embodiment, the power source 40 and the second electrode 20, but is otherwise different. This is mainly explained.

  The first electrode 130 of this embodiment is a coated wire in which a 0.08 mm diameter copper wire is coated with Teflon (trademark), and the tip is a plasma generation point 11. As shown in FIG. 6, the tip end of the first electrode 130 is in a state where the covered wire is cut, and the conductive member 31 that is a copper wire is exposed to form the generation point 11. The first electrode 130 is covered with a coating 32 except for the generation point 11.

  The second electrode 20 is connected to the power source 40 by a connection line 60 and grounded by a connection line 50. Thus, when an AC voltage or a pulse voltage is applied between the first electrode 130 and the second electrode 20 from the power source 40, the electric field is concentrated at the generation point 11 where the conductive member 31 is exposed. Plasma is generated only in the vicinity of the point 11.

  Furthermore, the plasma generator of this embodiment is provided with a gas introduction unit 80. A nozzle 85 is attached to the gas introduction unit 80, and an injection port of the nozzle 85 is placed in the vicinity of the generation point 11. A predetermined gas flows from the gas introduction unit 80 around the generation point 11 through the nozzle 85. The predetermined gas is a gas selected from various gases according to the purpose of plasma generation. For example, when Ar or He is introduced in the vicinity of the generation point 11, plasma is more easily generated than in the atmosphere. The gas type may be selected according to the wavelength of light to be used. When oxygen is introduced, ozone and oxygen radicals are generated. For example, when a specific organic molecule is to be bonded to the surface of the workpiece, a gas containing the organic molecule may be introduced. Further, when a resin coating is desired on the surface of the workpiece, a gas containing a monomer may be introduced.

  This embodiment has the same effects as those of the first embodiment, and various surface treatments, light irradiation, sterilization, and the like can be easily performed in a minute region by introducing a predetermined gas. In this case, various gases can be used.

(Embodiment 3)
As shown in FIG. 7, the plasma generator according to the third embodiment is the same as the plasma generator according to the first embodiment, the power source 40 and the second electrode 20, but is different because the other portions are different. This is mainly explained.

  In the first electrode 34 of the present embodiment, a Teflon (registered trademark) coating 32 is applied to the conductive member 33 as shown in FIG. The conductive member 33 is a cylinder having hemispheres at both ends, and is smoothly connected from the hemisphere to the cylinder. Further, the conductive member 33 has a protrusion 35 on a part of a cylinder, and the protrusion 35 is also provided with a coating 32 having the same thickness as other parts. A portion corresponding to the protrusion 35 of the first electrode 34 becomes the generation point 12.

  On the other hand, the second electrode 20 is placed in the vicinity of the generation point 12 and is grounded via the connection line 50 without being connected to the power source 40.

  When an AC voltage or a pulse voltage is applied from the power supply 40 to the first electrode 34, the electric field concentrates around the generation point 12 and plasma is generated only in this portion.

  This embodiment has the same effect as the first embodiment.

(Embodiment 4)
As shown in FIG. 9, the plasma generator according to the fourth embodiment is different from the plasma generator according to the third embodiment in the first electrode 36, but the other points are the same and are different. Is mainly explained.

  In the first electrode 36 of the present embodiment, a Teflon (registered trademark) coating 32 is applied to a conductive member 37 as shown in FIG. The conductive member 37 is an elliptical cylinder having an elliptical cross section, and both ends are smoothly rounded and terminated. A corner portion 38 having a substantially right angle is present at a part of the terminal end of the conductive member 37, and the corner portion 38 is covered with a coating 32 having the same thickness as the other portions. A portion corresponding to the corner portion 38 of the first electrode 36 becomes the generation point 13.

  On the other hand, the second electrode 20 is placed in the vicinity of the generation point 13 and is not connected to the power supply 40 but is grounded via the connection line 50.

  When an AC voltage or a pulse voltage is applied from the power source 40 to the first electrode 36, the electric field concentrates around the generation point 13 and plasma is generated only in this portion.

  This embodiment has the same effect as the first embodiment.

(Embodiment 5)
As shown in FIG. 11, the plasma generator according to the fifth embodiment is the same as the plasma generator according to the first embodiment, the power source 40 and the second electrode 20, but is different because the other portions are different. This is mainly explained.

  As shown in FIG. 12, the first electrode 230 of this embodiment is obtained by providing a linear conductive member 31 with an insulating coating 32, and the tip 32 has a coating 32 similar to other portions. Is provided. This tip portion is the generation point 14.

  The second electrode 20 is placed in the vicinity of the generation point 14 and is connected to the covered ground line 22 through the connection line 51. The covered ground wire 22 is a conductive wire covered with an insulating coating, and is inserted into the ground 1. On the other hand, the power source 40 is connected to the first electrode 230 and grounded by the ground line 70.

  When an AC voltage or a pulse voltage is applied from the power supply 40 to the first electrode 230, the electric field concentrates around the generation point 14 and plasma is generated only in this portion.

  The second electrode 20 is grounded through the coating, but an alternating voltage or a pulse voltage is applied between the second electrode 20 and the first electrode 230 due to dielectric polarization.

  This embodiment has the same effect as the first embodiment. Even if the second electrode 20 is not placed in the vicinity of the generation point 14, plasma is generated at the generation point 14 even if it is separated by, for example, 10 cm or more. This is because when the first electrode is linear, the electric field is very concentrated at the tip.

(Embodiment 6)
As shown in FIG. 13, the plasma generator according to the sixth embodiment is the same as the plasma generator according to the fifth embodiment, the power supply 40 and the first electrode 230, but is different in other respects. This is mainly explained. In the present embodiment, plasma is not generated at the tip of the first electrode 230.

  The second electrode 25 of the present embodiment is installed in the vicinity of the first electrode 230 but away from the tip of the first electrode 230. The second electrode 25 is made of a metal plate and has a teardrop shape, or in other words, an egg-shaped apex portion that is a corner portion 81. Then, it is not connected to the power supply 40 but is grounded via the connection line 50.

  In the present embodiment, when an AC voltage or a pulse voltage is applied from the power source 40 to the first electrode 230, the electric field concentrates on the portion 16 of the first electrode 230 closest to the corner 81 of the second electrode 25. Plasma is generated only in the vicinity. In order to reliably generate plasma in the portion 16, the tip of the first electrode 230 is separated from the second electrode 25 as much as possible, or the coating 32 at the tip of the first electrode 230 is more than the other portions. It is preferable that the thickness is increased or the insulating property is increased, or the corner of the outer peripheral edge of the second electrode 25 is dropped and rounded.

  This embodiment has the same effect as the first embodiment.

(Embodiment 7)
As shown in FIG. 14, the plasma generator according to the seventh embodiment is the same as the plasma generator according to the fifth embodiment, the power source 40 and the first electrode 230, but is different because the other portions are different. This is mainly explained. In the present embodiment, plasma is not generated at the tip of the first electrode 230.

  The second electrode 27 of the present embodiment is disposed in the vicinity of the first electrode 230 but away from the tip of the first electrode 230. The second electrode 27 is made of a metal plate, and has a protrusion 82 protruding toward the first electrode 230 on a part of the surface facing the first electrode 230. It is connected to the power source 40 and grounded via the connection line 50.

  In the present embodiment, when an AC voltage or a pulse voltage is applied from the power source 40 to the first electrode 230, the electric field concentrates on the portion 18 of the first electrode 230 closest to the protrusion 82 of the second electrode 27, and its surroundings. Plasma is generated only in In order to reliably generate plasma in the portion 18, the tip of the first electrode 230 is separated from the second electrode 27 as much as possible, or the coating 32 at the tip of the first electrode 230 is made more than other portions. It is preferable to increase the thickness, improve the insulation, or round the corners of the outer peripheral edge of the second electrode 27.

  This embodiment has the same effect as the first embodiment.

(Embodiment 8)
As shown in FIG. 15, the plasma generator according to the eighth embodiment is the same as the plasma generator according to the second embodiment in the power source 40, the first electrode 130, and the second electrode 20, but is otherwise different. Therefore, the differences are mainly explained.

  In the plasma generator of this embodiment, the first electrode 130 is inserted into the narrow tube 100. The thin tube 100 is made of PVC and is opaque, and its tip 101 is fitted with quartz glass so that visible light to ultraviolet light can be transmitted. Further, the gas introduction part 80 is attached to the end part on the opposite side of the tip 101 of the thin tube 100 via the adapter 87. The gas to be introduced is preferably Ar, He or the like that easily generates plasma and a gas that generates light having a desired wavelength.

  The present embodiment has the same effect as the first embodiment and can easily perform light irradiation in a minute region by introducing a predetermined gas. In particular, since it is configured to transmit light only from the tip 101 of the thin tube 100, it can be used as a micro light source with high directivity. In this case, various gases can be used.

(Other embodiments)
The above embodiments are examples of the present invention, and the present invention is not limited to these examples. For example, the shape of the conductive member of the first electrode may be any shape such as a plate shape, a foil shape, a rod shape, in addition to a linear shape.

  The discharge generated in the first electrode is not particularly limited, such as dielectric barrier discharge, glow discharge, corona discharge. Any discharge form may be used as long as plasma is generated.

  In Embodiment 6, the shape of the 2nd electrode 25 is not limited to said shape, What kind of thing may be sufficient if it is a shape which has the corner | angular part enclosed by the curve.

  You may attach the gas introduction part of Embodiment 2 to the plasma generator of other embodiment.

  The method for grounding the second electrode and the method for connecting to the power supply may be any of the above-described embodiments. For example, in Embodiment 1, the grounding method of Embodiment 3 (including grounding of the power supply 40) is used. It may be adopted.

  The place where plasma is generated in the first electrode is not limited to one place, and may be a plurality of places. That is, one first electrode may have a plurality of covering portions having a higher dielectric constant than other portions, or may have a plurality of protruding portions and corner portions, and these may be one first electrode. They may be combined in the electrode. In the sixth and seventh embodiments, a plurality of corners or protrusions of the second electrode may exist.

  As described above, the plasma generation apparatus and the plasma generation method according to the present invention can easily generate minute plasma, and are useful as a sterilization apparatus / method, a light source, a surface treatment apparatus / method, and the like.

1 is a schematic diagram of a plasma generator according to Embodiment 1. FIG. It is sectional drawing of a 1st electrode. It is an enlarged view of the 1st electrode. It is a figure which shows a pulse voltage. 6 is a schematic diagram of a plasma generator according to Embodiment 2. FIG. It is a figure which shows the generation | occurrence | production point which concerns on Embodiment 2. FIG. FIG. 6 is a schematic diagram of a plasma generator according to a third embodiment. It is a figure which shows the generation | occurrence | production point which concerns on Embodiment 3. FIG. FIG. 6 is a schematic diagram of a plasma generator according to a fourth embodiment. It is a figure which shows the generation | occurrence | production point which concerns on Embodiment 4. FIG. FIG. 9 is a schematic diagram of a plasma generator according to a fifth embodiment. It is a figure which shows the generation | occurrence | production point which concerns on Embodiment 5. FIG. FIG. 10 is a schematic diagram of a plasma generator according to a sixth embodiment. FIG. 10 is a schematic diagram of a plasma generator according to a seventh embodiment. FIG. 10 is a schematic diagram of a plasma generator according to an eighth embodiment.

Explanation of symbols

10, 11, 12 Generation point 13, 14 Generation point 20, 25, 27 Second electrode 30, 34, 36 First electrode 31, 33, 37 Conductive member 32 Cover 35 Projection 38 Corner 40 Power supply 80 Gas introduction (Gas inflow member)
81 corner 82 protrusion 130 first electrode 230 first electrode

Claims (12)

A first electrode comprising a conductive member coated with an insulator or dielectric;
A power source for applying an alternating voltage or a pulse voltage to the first electrode,
The first electrode is a coated metal wire;
A portion of the insulator or dielectric coating of the first electrode is made thinner than a portion other than the portion,
Generating a spot-like plasma by dielectric barrier discharge in the part, the plasma generating apparatus.   The plasma generator according to claim 1, further comprising a second electrode connected to the power source and applied with the AC voltage or pulse voltage between the first electrode and the first electrode.   The plasma generator according to claim 1, further comprising a ground electrode connected to the power source and applied with the AC voltage or pulse voltage between the first electrode and the first electrode.   The plasma generating apparatus according to claim 1, further comprising a gas introduction unit that introduces a predetermined gas around at least the part.   The surface treatment apparatus provided with the plasma generator as described in any one of Claim 1 to 4 which performs the surface treatment of a workpiece by the said plasma.   The light source provided with the plasma generator according to claim 1, wherein ultraviolet light or visible light generated from the plasma is used. A first electrode having a conductive member covered with an insulator or a dielectric, wherein a part of the insulator or the dielectric is made thinner than a portion other than the part is disposed at a predetermined position. The process of installing in
By applying an AC voltage or pulse voltage to the first electrode, and a plasma generating step of generating a spot-like plasma by dielectric barrier discharge in the part,
The plasma generation method, wherein the first electrode is a coated metal wire.   In the plasma generation step, plasma is generated by applying the AC voltage or pulse voltage between the first electrode and a second electrode placed in the vicinity of the first electrode. The plasma generation method described.   The plasma generation method according to claim 7, wherein in the plasma generation step, plasma is generated by applying the AC voltage or pulse voltage between the first electrode and a ground electrode.   The plasma generation method according to claim 7, wherein in the plasma generation step, a predetermined gas is introduced at least around the part.   A surface treatment method for performing a surface treatment of a workpiece with plasma generated by the plasma generation method according to claim 7.   A light irradiation method using ultraviolet light or visible light generated from the plasma generated by the plasma generation method according to claim 7.

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