JP4501703B2 - Plasma processing equipment - Google Patents

Description

  The present invention relates to an apparatus and method for processing a filamentous object for plasma processing of a filamentous object, and more particularly to a plasma processing apparatus for performing a surface treatment of conductors and terminals of electronic components.

  An example of the thread-like object is a terminal portion of a coil. This is a coated wire in which the surface of a wire mainly composed of copper is coated with a resin typified by an enameled wire.

  By using plasma on the solder joint surface of the printed circuit board in advance, especially by using low-temperature atmospheric pressure plasma, which is advantageous in terms of equipment cost and footprint, it realizes good solder joint without using flux The technique is described in US Pat.

  However, as represented by plasma processing on printed circuit boards, the purpose of surface treatment with low-temperature atmospheric pressure plasma is to clean the bonding surface and to modify the surface, which is relatively thick like organic coating of coated wire There is a problem that enormous processing time is required to apply to the removal method of the film (50 μm).

  As a method for solving this problem, the organic coating film can be removed in a short time by a method for generating a high-density microplasma in a minute region as described in Patent Document 2.

  As a conventional example of the plasma treatment for the filamentous object by the microplasma, the surface treatment of the conductive wire will be described with reference to FIG. 17, taking a rectangular parallelepiped microplasma treatment apparatus as an example.

  In addition, the conducting wire generally means a coated wire in which the surface of a wire mainly composed of copper is coated with a resin represented by an enameled wire, and the resin is a polyurethane-based, imide-based, or polyester-based resin. It is done.

The microplasma source includes a dielectric cylinder 2 and two electrodes 3 and 4 opposed to each other with the dielectric cylinder 2 interposed therebetween, and a gas supply device (not shown) for supplying gas into the dielectric cylinder 2 And a power source (not shown) for supplying power between the two electrodes 3 and 4. From the right to the left of the figure, a high frequency voltage or high frequency of several hundred kHz to several GHz is pulse-modulated between the electrodes 3 and 4 while supplying a mixed gas of a rare gas and a reactive gas into the dielectric cylinder 2. The plasma 9 is generated in the dielectric cylinder 2 by supplying a pulsed DC voltage. By inserting a conducting wire into the dielectric cylinder 2 and generating the plasma 9, the resin coating can be removed from the conducting wire as shown in FIG.
JP 09-235686 A JP 2004-363152 A

  However, in the plasma processing of the conventional example, when the processing object comes into contact with the inner wall in the plasma processing region in the dielectric cylinder 2 during the plasma irradiation, the plasma processing is performed on the contacted portion of the processing object. There has been a problem that it is not applied or the processing speed is reduced.

  In the plasma processing of the conductive wire described with reference to FIG. 17, if the conductive wire 1 is in contact with the inner wall surface of the plasma irradiation portion of the dielectric cylinder 2, the contact surface is not irradiated with plasma, and the resin coating is not performed. Not removed. In particular, when an adhesive component is included in addition to the resin coating, the adhesive melts due to the heat of the plasma, and the conductive wire 1 is bonded to the inner wall surface of the dielectric cylinder 2.

  From such circumstances, it is necessary to install the conductor 1 so as not to contact the inner wall surface of the dielectric cylinder 2 during the plasma treatment. When the conductor 1 contacts the inner wall surface of the dielectric cylinder 2, It was necessary to carry out the plasma treatment again after re-installing the conductors.

  On the other hand, because of the characteristics of microplasma, the greater the distance between the electrodes, the more difficult it is to generate plasma, so the space inside the dielectric cylinder 2 is inevitably narrowed. For this reason, it was very difficult to install the conductor 1 so as not to contact the inner wall surface of the dielectric cylinder 2. At the same time, since the insertion port for the object to be processed is also narrow, it is difficult to insert the conductive wire 1 into the dielectric cylinder 2.

  In view of the above-described conventional problems, the present invention has a structure in which an object to be processed can be easily installed even in a narrow space, so that a plasma can be performed without causing the object to be processed to contact the inner wall. An object is to provide a processing apparatus.

The plasma processing apparatus of the present gun onset Ming, a cylinder having an insertion port of the article to be treated, a guide for supporting an object to be processed, an electrode disposed across the tube, which is connected to the tube A plasma processing apparatus comprising: a gas supply device; and a power supply device that supplies a high-frequency voltage to the electrode, wherein the tube and the guide are disposed with a space, and the guide includes the guide A taper is provided so that the workpiece insertion port is narrowed toward the inside, and the inner diameter of the cross section perpendicular to the insertion direction of the workpiece inside the guide is the inscribed circle having the smallest diameter. A first space is provided, the cylinder has a second space constituted by an inscribed circle larger than the diameter of the first space, and the electrode is not positioned on the outer periphery of the guide. It is characterized by that.

  With such a configuration, it is possible to perform a desired plasma process without bringing the object to be processed into contact with the inner wall.

In the plasma processing apparatus of the present gun onset bright, preferably, the guide inner diameter of the inscribed circle diameter of the smallest space, the cylindrical inner space, of the inscribed circle in a space and between the electrodes forms It is desirable to be smaller than the minimum value of the diameter by 0.02 mm or more and 2 mm or less.

  Preferably, the guide is preferably provided at least on the insertion port side of the workpiece.

  Preferably, the guide is provided apart from the cylinder.

As described above, according to the plasma processing apparatus of the present invention, since the insertion port of the object to be processed has a tapered shape, the object to be processed can be easily installed even in a narrow space. In comparison, since the plasma irradiation portion is wide, a desired plasma treatment can be performed without bringing the workpiece into contact with the inner wall.

  Embodiments of the present invention will be described below with reference to the drawings.

(Embodiment 1)
Hereinafter, a first embodiment of the present invention will be described with reference to FIGS.

  FIG. 1 is a perspective view showing a schematic configuration of a microplasma processing apparatus for removing a resin coating on a conductive wire used for an electronic component. In FIG. 1, the conducting wire 1 is generally a coated wire in which a resin is coated on the surface of a wire material mainly composed of copper. The microplasma source includes a dielectric cylinder 2 and electrodes 3 and 4 facing each other with the dielectric cylinder 2 interposed therebetween, and a gas supply device 5 for supplying gas into the dielectric cylinder 2 and between the two electrodes. And a power source 6 for supplying power to the power source. By supplying power from the power source 6 between the electrodes 3 and 4 while supplying a mixed gas of a rare gas and a reactive gas from the gas supply device 5 into the dielectric cylinder 2, the dielectric cylinder 2 is supplied into the dielectric cylinder 2. Local plasma (not shown) can be generated, and the resin coating of the conductor 1 can be removed by generating plasma while the conductor 1 is inserted into the dielectric cylinder 2.

  In the present embodiment, the electrodes 3 and 4 are provided with only one pair facing each other with the dielectric cylinder 2 in between. However, the positions of the electrodes 3 and 4 are shifted from the facing state, or two or more pairs are provided. It may be done. Alternatively, the electrodes 3 and 4 may be cylindrical and arranged as shown in FIG.

  FIG. 3 is a cross-sectional view of the microplasma source and the lead 1 of the electronic component. The conducting wire 1 is a covered wire, and the surface of a wire 7 containing copper as a main component is covered with a resin 8. By supplying a high frequency voltage of 13.56 MHz between the electrodes 3 and 4 while supplying a mixed gas of a rare gas and a reactive gas into the dielectric cylinder 2 from the right to the left in the figure, Plasma 9 is generated in the cylinder 2. The applied voltage may be a high frequency voltage of several hundred kHz to several GHz, a pulse modulated high frequency, or a pulsed direct current. Such a plasma source can operate from several Pa to several atmospheres, but typically operates at a pressure in the range of about 10,000 Pa to 3 atmospheres. In particular, operation near atmospheric pressure is preferable because a strict sealing structure and a special exhaust device are not required, and diffusion of plasma and active particles is moderately suppressed.

  Further, a taper 10 is provided at the workpiece insertion port of the dielectric cylinder 2, and the taper 10 serves as a guide, so that the conductor 1 can be easily inserted into the dielectric cylinder 2. It is possible.

  FIG. 4 is a cross-sectional view of a state in which plasma is applied to the lead wires of the electronic component. The conducting wire 1 is inserted into the plasma 9 generated in the dielectric cylinder 2 and irradiated with the plasma 9. Then, active particles in the plasma are volatilized by chemical reaction with the coated resin 8, and the wire 7 is exposed at the tip of the inserted conductor 1.

  Note that generation of plasma requires a rare gas, a reactive gas, and electric power, and the plasma 9 may be generated by supplying the gas after inserting the conducting wire 1 in order to reduce running costs.

  5A and 5B are cross-sectional views of the microplasma source taken along dotted lines a-a ′ and b-b ′ in FIG. 4, respectively. From the diameter (R ′) of the region formed between the electrodes 3 and 4 among the diameters of the maximum circle 11 inscribed in the cross section cut by the plane perpendicular to the insertion direction of the conducting wire in the region in the dielectric cylinder 2. A region having a short diameter (R) is provided (R ′> R). By providing this region not only on the insertion port side of the object to be processed but also on the gas inlet side, it is possible to reliably perform processing even when the object to be processed is long and soft. . The minimum value of the diameter is shorter than the minimum value of the diameter of the region formed between the electrodes 3 and 4 by 0.02 mm or more and 2 mm or less. When the difference is smaller than this range, the workpiece and the wall surface are in contact with each other, and when the difference is larger, the discharge start voltage of the plasma is increased. However, in the case of the electrode arrangement as shown in FIG. 2, as shown in FIG. 6, the region formed between the electrodes 3 and 4 indicates a region surrounded by the electrodes 3 and 4 and a region formed by the region. With such a configuration, it is possible to prevent the conductive wire 1 from coming into contact with the inner wall surface of the dielectric cylinder 2 in the plasma irradiation portion, and it is possible to avoid the problem that an untreated portion remains in the conductive wire 1.

  In addition, an inclination 12 is provided on the inner wall of the dielectric cylinder 2 between the plasma irradiation portion in the dielectric cylinder 2 and the insertion port for the object to be processed and the inlet for the mixed gas, so that the flow of the mixed gas can be reduced. Disturbance can be prevented and reaction efficiency can be improved.

  Note that the inclination angle of the taper 10 described with reference to FIG. 3 is provided so that the extended line of the taper 10 hits the wall surface between the taper 10 and the inclination 12. With such a configuration, it is possible to prevent the conducting wire whose insertion direction has been corrected by the taper 10 from directly contacting the wall surface of the region formed between the electrodes 3 and 4.

(Embodiment 2)
Next, a second embodiment of the present invention will be described with reference to FIGS.

  FIG. 7 is a cross-sectional view of the lead 1 for the microplasma source and the electronic component. The conducting wire 1 is generally a coated wire in which a resin 8 is coated on the surface of a wire 7 containing copper as a main component. The microplasma source includes a dielectric cylinder 2, a guide 13 that supports the conducting wire 1, and two electrodes 3 and 4 that are opposed to each other with the dielectric cylinder 2 interposed therebetween, and supplies gas into the dielectric cylinder 2. A gas supply device (not shown), and a power supply (not shown) for supplying power between the two electrodes. By supplying a high frequency voltage of 13.56 MHz between the electrodes 3 and 4 while supplying a mixed gas of a rare gas and a reactive gas into the dielectric cylinder 2 from the right to the left in the figure, Plasma 9 is generated in the cylinder 2. The applied voltage may be a high frequency voltage of several hundred kHz to several GHz, a pulse modulated high frequency, or a pulsed direct current. Such a plasma source can operate from several Pa to several atmospheres, but typically operates at a pressure in the range of about 10,000 Pa to 3 atmospheres. In particular, operation near atmospheric pressure is preferable because a strict sealing structure and a special exhaust device are not required, and diffusion of plasma and active particles is moderately suppressed.

  The conducting wire 1 is inserted into the dielectric cylinder 2 through the guide 13. A taper 14 is provided at the workpiece insertion port of the guide 13 so that the conductor 1 can be easily passed through the guide 13.

  The angle of the taper 14 and the length of the guide 13 are such that the extension line hits the inner wall of the guide 14. With such a configuration, it is possible to more reliably prevent the lead wire 1 from contacting the wall surface in the dielectric cylinder 2.

  In addition, although the cylindrical shape is described in the drawing regarding the shape of the guide 13, it is not necessary to stick to this shape, and any shape that can support the conducting wire may be used. For example, a shape in which a conductive wire is sandwiched between a plurality of claw-like objects may be used.

  In the present embodiment, the electrodes 3 and 4 are provided with only one pair facing each other with the dielectric cylinder 2 in between. However, the positions of the electrodes 3 and 4 are shifted from the facing state, or two or more pairs are provided. It may be done. Moreover, you may make the shape of the electrodes 3 and 4 into a cylinder shape like FIG.

  FIG. 8 is a cross-sectional view of a state in which a lead wire of an electronic component is inserted into a microplasma source and plasma is irradiated. The conducting wire 1 is inserted into the plasma 9 generated in the dielectric cylinder 2 and irradiated with the plasma 9. Then, active particles in the plasma are volatilized by chemical reaction with the coated resin 8, and the wire 7 is exposed at the tip of the inserted conductor 1.

  In order to generate plasma, a rare gas, a reactive gas, and electric power are required, and the plasma 9 may be generated by supplying gas while inserting the conducting wire 1 in order to reduce running cost.

  FIGS. 9A and 9B are cross-sectional views of the microplasma source taken along dotted lines a-a ′ and b-b ′ in FIG. 8, respectively. In the diameter of the maximum circle 11 inscribed in a cross section cut by a plane perpendicular to the insertion direction of the conducting wire, the maximum value (R) of the area in the guide 13 is the area in the dielectric cylinder 2 and the electrode. A region shorter than the minimum value (R ′) of the diameter of the region formed between 3 and 4 is provided (R ′> R). A guide having this region is also provided on the gas inlet side, or on the gas inlet side of the region between the electrodes 3 and 4 in the dielectric cylinder 2 or the region surrounded by the coil. In addition, even when the object to be processed is long and soft, it is possible to reliably perform the processing. The minimum value of this diameter is 0.02 mm or more and 2 mm or less shorter than the minimum value of the diameter of the region formed between the electrodes 3 and 4 or the region surrounded by the coil. When the difference is smaller than this range, the workpiece and the wall surface are in contact with each other, and when the difference is larger, the discharge start voltage of the plasma is increased. However, in the case of the arrangement of the electrodes as shown in FIG. 2, the region formed between the electrodes 3 and 4 indicates a region surrounded by the electrodes 3 and 4 and a region formed by the region. With such a configuration, it is possible to prevent the conductive wire 1 from coming into contact with the inner wall surface of the dielectric cylinder 2 in the plasma irradiation portion, and it is possible to avoid the problem that an untreated portion remains in the conductive wire 1. In addition, there is a gap between the dielectric cylinder 2 and the guide 13, and by letting the gas escape there, it becomes possible to prevent the disturbance of the flow due to the reduction of the diameter of the gas flow path, and increase the reaction efficiency. it can.

(Embodiment 3)
Next, a third embodiment of the present invention will be described with reference to FIGS.

  FIG. 10 is a perspective view showing a schematic configuration of a microplasma processing apparatus for removing a resin coating on a conductive wire used for an electronic component. In FIG. 10, the conducting wire 1 is generally a coated wire in which a resin is coated on the surface of a wire material mainly composed of copper. The microplasma source includes a dielectric cylinder 2 and electrodes 3 and 4 facing each other with the dielectric cylinder 2 interposed therebetween, and a gas supply device 5 for supplying gas into the dielectric cylinder 2 and between the two electrodes. And a power source 6 for supplying power to the power source. The dielectric cylinder 2 forms a generally T-shaped space inside, and the conductor 1 may be inserted from one of them, and gas may be supplied from one of the remaining two, or gas may be supplied from both. You may make it supply. Further, the shape inside the dielectric cylinder 2 may be substantially cross-shaped, and one may be supplied to the insertion opening of the conducting wire, and gas may be supplied from at least one of the remaining three sides, or a shape having a plurality of branches However, from the viewpoint of gas outflow, a large number of branches will lower the reaction efficiency. When electric power is supplied from the power source 6 between the electrodes 3 and 4 while supplying a mixed gas of a rare gas and a reactive gas from the gas supply device 5 into the dielectric cylinder 2, the dielectric cylinder 2 is localized in the dielectric cylinder 2. Plasma (not shown) can be generated, and the resin coating of the conductor 1 can be removed by inserting the conductor 1 into the dielectric cylinder 2 and generating plasma.

  In the present embodiment, the electrodes 3 and 4 are provided with only one pair facing each other with the dielectric cylinder 2 in between. However, the positions of the electrodes 3 and 4 are shifted from the facing state, or two or more pairs are provided. It may be done. Further, the electrodes 3 and 4 may be formed in a cylindrical shape and arranged as shown in FIG.

  12A and 12B are cross-sectional views taken along planes (A) and (B) in FIG. 10, respectively. The conducting wire 1 is generally a coated wire in which a resin 8 is coated on the surface of a wire 7 containing copper as a main component. While supplying a mixed gas of a rare gas and a reactive gas into the dielectric cylinder 2 from the right to the left in FIGS. 12A and 12B and from the bottom to the top in FIG. 12B, the electrodes 3 and 4 are supplied. By supplying a high frequency voltage of 13.56 MHz between them, plasma 9 is generated in the dielectric cylinder 2. The applied voltage may be a high frequency voltage of several hundred kHz to several GHz, a pulse modulated high frequency, or a pulsed direct current. Such a plasma source can operate from several Pa to several atmospheres, but typically operates at a pressure in the range of about 10,000 Pa to 3 atmospheres. In particular, operation near atmospheric pressure is preferable because a strict sealing structure and a special exhaust device are not required, and diffusion of plasma and active particles is moderately suppressed.

  The workpiece insertion port of the dielectric cylinder 2 is provided with a taper 10, and the taper 10 serves as a guide, so that the conducting wire 1 can be easily inserted into the dielectric cylinder 2. ing.

  13 is a cross-sectional view of a state in which plasma is applied to the lead wires of the electronic component, (A) is a cross-sectional view taken along plane (A) in FIG. 10, and (B) is a plane view in FIG. It is sectional drawing cut | disconnected by B). The conducting wire 1 is inserted into the plasma 9 generated in the dielectric cylinder 2 and irradiated with the plasma 9. Then, active particles in the plasma are volatilized by chemical reaction with the coated resin 8, and the wire 7 is exposed at the tip of the inserted conductor 1.

  Note that generation of plasma requires a rare gas, a reactive gas, and electric power, and the plasma 9 may be generated by supplying the gas after inserting the conducting wire 1 in order to reduce running costs.

  Further, in FIG. 13, the conducting wires are arranged on a straight line, but as shown in FIG. 14, they may be arranged so as to be generally L-shaped. However, FIG. 14 is a cross-sectional view cut along a horizontal plane passing between the electrodes 3 and 4.

  FIGS. 15A and 15B are cross-sectional views of the microplasma source taken along dotted lines a-a ′ and b-b ′ in FIG. 13, respectively. In the region in the dielectric cylinder 2, the diameter (R ′) of the region formed between the electrodes 3 and 4 in the diameter (R) of the maximum circle 11 inscribed in the cross section cut by the plane perpendicular to the insertion direction of the conducting wire. ) A region having a shorter diameter is provided (R ′> R). By providing this area not only at the insertion port side of the workpiece, but also at other openings, it is reliable even when the workpiece is long, soft, or bent at a substantially right angle. It becomes possible to perform processing. The minimum value of the diameter is shorter than the minimum value of the diameter of the region formed between the electrodes 3 and 4 by 0.02 mm or more and 2 mm or less. When the difference is smaller than this range, the workpiece and the wall surface are in contact with each other, and when the difference is larger, the plasma discharge start voltage is increased. However, in the case of the arrangement of the electrodes as shown in FIG. 11, as shown in FIGS. 16A and 16B, the region formed between the electrodes 3 and 4 is the region surrounded by the electrodes 3 and 4, An area formed by an area. With such a configuration, it is possible to prevent the conductive wire 1 from coming into contact with the inner wall surface of the dielectric cylinder 2 in the plasma irradiation portion, and it is possible to avoid the problem that an untreated portion remains in the conductive wire 1. In addition, an inclination 12 is provided on the inner wall of the dielectric cylinder 2 between the plasma irradiation portion in the dielectric cylinder 2 and the insertion port for the object to be processed and the inlet for the mixed gas, so that the flow of the mixed gas can be reduced. Disturbance can be prevented and reaction efficiency can be improved.

  The inclination angle of the taper 10 described with reference to FIG. 12 is provided so that the extension line of the taper 10 hits the wall surface between the taper 10 and the inclination 12. With such a configuration, it is possible to prevent the conducting wire whose insertion direction has been corrected by the taper 10 from directly contacting the wall surface of the region formed between the electrodes 3 and 4.

  The apparatus for processing a thread-like object of the present invention is an apparatus that can effectively peel off the resin coating of the terminal part of the electronic component, a processing apparatus that plating lead-free solder on the terminal part of the electronic part, and the electronic part in the lead-free solder mounting process The processing apparatus to which it adapts can be provided, and it can apply to the process of manufacturing electronic parts including a coil and a transformer, and the process of mounting electronic parts.

The perspective view which shows schematic structure of the microplasma processing apparatus in Embodiment 1 of this invention. The perspective view which shows schematic structure of the other microplasma processing apparatus in Embodiment 1 of this invention. Sectional drawing which shows the state which inserts conducting wire in the microplasma source in Embodiment 1 of this invention Sectional drawing which shows the state which is irradiating plasma to conducting wire in Embodiment 1 of this invention 4A is a cross-sectional view of the microplasma processing apparatus cut along a dotted line a-a ′ in FIG. 4, and FIG. 4B is a cross-sectional view of the microplasma processing apparatus cut along a dotted line b-b ′ in FIG. 4. Sectional drawing which shows the state which has irradiated the conducting wire in the other apparatus in Embodiment 1 of this invention Sectional drawing which shows the state which inserts conducting wire in the microplasma source in Embodiment 2 of this invention Sectional drawing which shows the state which is irradiating plasma to conducting wire in Embodiment 2 of this invention (A) Cross-sectional view of the microplasma processing apparatus cut along a dotted line a-a 'in FIG. 8, (B) Cross-sectional view of the microplasma processing apparatus cut along a dotted line b-b' in FIG. The perspective view which shows schematic structure of the microplasma processing apparatus in Embodiment 3 of this invention. The perspective view which shows schematic structure of the other microplasma processing apparatus in Embodiment 3 of this invention. (A) Cross-sectional view in a vertical plane showing a state in which the conducting wire is inserted into the microplasma source in Embodiment 3 of the present invention, (B) State in which the conducting wire is inserted into the microplasma source in Embodiment 3 of the present invention. Cross section at horizontal plane (A) Sectional view at plane (A) in FIG. 10 showing a state in which plasma is applied to the conducting wire in Embodiment 3 of the present invention, (B) Plasma is applied to the conducting wire in Embodiment 3 of the present invention. Sectional drawing in the plane (B) in FIG. 10 which shows the state which is carrying out Sectional drawing in the plane (B) in FIG. 10 which shows the state which is irradiating the plasma to the conducting wire in the other conducting wire insertion method in Embodiment 3 of this invention FIG. 13A is a cross-sectional view of the microplasma processing apparatus cut along a dotted line a-a ′ in FIG. 13A, and FIG. 13B is a cross-sectional view of the microplasma processing apparatus cut along a dotted line b-b ′ in FIG. (A) Cross-sectional view at plane (A) in FIG. 10 showing a state in which plasma is applied to the conducting wire in another apparatus according to the third embodiment of the present invention, (B) in the third embodiment of the present invention. Sectional drawing in the plane (B) in FIG. 10 which shows the state which is irradiating plasma to conducting wire in another apparatus. Sectional drawing which shows the state which irradiates plasma to a conducting wire in a prior art example

DESCRIPTION OF SYMBOLS 1 Conductor 2 Dielectric cylinder 3 Electrode 4 Electrode 5 Gas supply device 6 Power supply 7 Wire material 8 Resin 9 Plasma 10 Taper 11 Inscribed circle 12 Inclination

Claims (4)

A cylinder having an insertion port for the object to be processed, a guide for supporting the object to be processed, an electrode arranged with the cylinder interposed therebetween, a gas supply device connected to the cylinder, and a high-frequency voltage applied to the electrode A plasma processing apparatus comprising: a power supply device for supplying
The cylinder and the guide are arranged with a space, and the guide is tapered so that a workpiece insertion port is narrowed toward the inside of the guide, and the workpiece inside the guide A first space constituted by an inscribed circle having a minimum diameter is provided in a cross section perpendicular to the insertion direction of the first, and the cylinder is provided with an inscribed circle constituted by an inscribed circle larger than the diameter of the first space. A plasma processing apparatus having two spaces and a structure in which the electrode is not positioned on an outer periphery of the guide. The diameter of the inscribed circle in which the diameter of the space inside the guide is the smallest is 0.02 mm or more and 2 mm compared with the minimum value of the diameter of the inscribed circle in the space inside the cylinder and the space formed between the electrodes. hereinafter is smaller, the plasma processing apparatus according to claim 1. The plasma processing apparatus according to claim 1 , wherein the guide is provided at least on an insertion port side of an object to be processed. The plasma processing apparatus according to claim 1 , wherein the guide is provided apart from the tube.

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