JP2008066058A - Plasma generation nozzle, plasma generating device, and work treatment device using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent an arc discharge (abnormal discharge) in a plasma generation nozzle which is used in a plasma generating device used for the treatment of a work or the like such as the reforming of a substrate, has an inner conductor and an outer conductor of concentric shapes, generates plasma by generating a glow discharge by impressing a high frequency pulse field between both electrodes, and by supplying treatment gas between the electrodes from a gas supply source, irradiates plasmolyzed gas on the work to be treated from a blowing port at normal pressure. <P>SOLUTION: A protection tube 36 composed of a dielectric such as cylindrical glass is installed in a cylindrical space 322 being a blowing port formed of a center conductor 32 being an inner conductor and a nozzle body 33 being an outer conductor of concentric shapes, and its tip face 361 is formed protruded in an axial direction so that the arc discharge ARC in an arc shape may not be generated between tip faces 3221, 331 of the center conductor 32 and the nozzle body 33. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a plasma generating nozzle, a plasma generating apparatus, and a work using the same, which are capable of purifying or modifying the surface of the work by irradiating the work to be processed such as a substrate with plasma. The present invention relates to a processing apparatus.

For example, there is known a workpiece processing apparatus that irradiates a workpiece to be processed such as a semiconductor substrate with plasma and removes organic contaminants on the surface, surface modification, etching, thin film formation, or thin film removal. For example, Patent Document 1 uses a plasma generation nozzle having concentric inner conductors and outer conductors, and applies a high-frequency pulse electric field between the two conductors, thereby generating glow discharge instead of arc discharge. The plasma is generated, and a high-density plasma is generated by turning the processing gas from the gas supply source from the base end side to the free end side while swirling between both conductors, and is attached to the free end. A plasma processing apparatus is disclosed in which high-density plasma can be obtained under normal pressure by radiating a workpiece to be processed from a nozzle.
JP 2003-197397 A

  In the above-described prior art, first, the inner conductor protrudes from the outer conductor to prevent arc discharge. Further, the inner periphery of the tip portion of the outer conductor is formed in a tapered shape, and arc discharge is prevented by increasing the distance from the tip portion of the inner conductor. Therefore, there is a problem that the distance between the tips where the electric field should be concentrated becomes wider than that in the case where they are flush with each other and it is difficult to turn on the plasma.

  An object of the present invention is to provide a plasma generating nozzle, a plasma generating apparatus, and a plasma generating nozzle capable of preventing arc discharge in a state in which the inner conductor capable of obtaining good ignitability is set back or flush with the outer conductor. It is to provide a work processing apparatus to be used.

  The plasma generating nozzle of the present invention has a concentric inner conductor and outer conductor, and generates a plasma by generating a glow discharge by applying a high-frequency pulse electric field between both electrodes. In a plasma generating nozzle that radiates plasma gas from a blow-out port under normal pressure to a workpiece to be processed by supplying a processing gas from a gas supply source therebetween, a cylinder is provided between the inner conductor and the outer conductor. And a tip surface of the inner conductor and the outer conductor is disposed in a state where the tip surface of the inner conductor is disposed in a state of being flush with or inward of the tip surface of the outer conductor. The front end surface of the dielectric is disposed so as to protrude in the axial direction from the front end surface of at least one of the inner conductor and the outer conductor so that no arc discharge occurs between them.

  According to the above configuration, in the plasma generation apparatus that can be used for workpiece processing such as substrate modification, the plasma generation nozzle has concentric inner conductors and outer conductors, and a space between them. By applying a high-frequency pulsed electric field to the arc, not an arc discharge (abnormal discharge), but a glow discharge is generated to generate plasma, and a processing gas from a gas supply source is supplied between them to blow out When configured to radiate plasma gas from the mouth under normal pressure to the workpiece, a cylindrical dielectric is provided in the outlet, and the tip surface of the inner conductor is first the tip surface of the inner conductor. The inner conductor is disposed so as to be flush with or inward of the front end surface of the outer conductor, and further, the inner conductor is prevented from generating arc discharge between the front end surfaces of the inner conductor and the outer conductor. Conductive And disposing projects axially from at least one of the front end surface of the outer conductor. For example, the tip surfaces of the inner conductor and the outer conductor are flush with each other, the tip surface of the dielectric protrudes from them, or the tip surface of the outer conductor and the tip surface of the dielectric are flush with each other, For example, the front end surface of the inner conductor is retracted from the front surface.

  Therefore, it is possible to obtain good ignitability, suppress occurrence of inadvertent arc discharge, and stably continue glow discharge, that is, plasma generation.

  In the plasma generating nozzle of the present invention, the amount of the protrusion is 1 mm or more.

  According to said structure, the effect of suppressing the said arc discharge (abnormal discharge) is high and it is suitable for the amount of the said protrusion to be 1 mm or more.

  Furthermore, in the plasma generating nozzle of the present invention, the dielectric is made of a quartz glass pipe.

  According to said structure, a quartz glass pipe has high corrosion resistance with respect to a plasma, and is suitable as said dielectric material.

  In the plasma generator of the present invention, the microwave generated by the microwave generating means is propagated through the waveguide, and a plurality of the plasma generating nozzles are arranged in the waveguide in the plasma generator. The microwave is received by the inner conductor of the plasma generating nozzle and generates a plasma gas with the outer conductor that is grounded through the waveguide. And release.

  According to the above configuration, when a plurality of plasma generating nozzles are used, a plasma generating nozzle that can prevent arcing (abnormal discharge) and generate stable plasma with each plasma generating nozzle as described above is suitable. It is possible to perform batch processing of a large-area workpiece or a plurality of workpieces. In addition, when a waveguide is used for microwave propagation, the plasma generating nozzle that does not cause undesired reflection due to the arcing (abnormal discharge) is preferable.

  Furthermore, the workpiece processing apparatus of the present invention comprises a moving means for moving the workpiece and the plasma generating nozzle relative to each other on a plane intersecting the plasma irradiation direction. A predetermined process is performed by irradiating the workpiece with plasma while moving.

  According to said structure, the workpiece | work of a big area can be continuously processed.

  As described above, the plasma generating nozzle of the present invention is a plasma generating apparatus that can be used for workpiece processing, such as substrate modification, and the plasma generating nozzle includes a concentric inner conductor and outer conductor. By applying a high-frequency pulse electric field between them, instead of arc discharge (abnormal discharge), a glow discharge is generated to generate plasma, and a processing gas from a gas supply source is generated between them. When it is configured to radiate plasma gas from the blowout port under normal pressure to the workpiece to be processed, a cylindrical dielectric is provided in the blowout port. Arranged so that the front end surface of the conductor is flush with or inward of the front end surface of the outer conductor, and an arc discharge is generated in which an arc is drawn between the front end surfaces of the inner conductor and the outer conductor. Oddly, it arranged to project axially from at least one of the front end surface of the inner conductor and the outer conductor.

  Therefore, it is possible to obtain good ignitability, suppress occurrence of inadvertent arc discharge, and stably continue glow discharge, that is, plasma generation.

  In addition, as described above, when using a plurality of plasma generating nozzles, the plasma generating apparatus of the present invention propagates the microwave generated by the microwave generating means through the waveguide, and the plasma generating unit The plurality of plasma generating nozzles are arranged and attached to the waveguide.

  Therefore, when using a plurality of plasma generating nozzles, the plasma generating nozzles that can prevent arcing (abnormal discharge) and generate stable plasma with each plasma generating nozzle as described above can be suitably used. , Large-area workpieces and batch processing of multiple workpieces can be performed. In addition, when a waveguide is used for propagation of microwaves, the plasma generating nozzle that does not cause undesired reflection due to the arcing (abnormal discharge) is preferable.

  Furthermore, the work processing apparatus of the present invention, as described above, has moving means for moving the work and the plasma generating nozzle relative to each other on a plane intersecting the plasma irradiation direction. The workpiece is irradiated with plasma and subjected to a predetermined treatment while performing relative movement.

  Therefore, a workpiece having a large area can be continuously processed.

  FIG. 1 is a perspective view showing an overall configuration of a work processing apparatus S according to an embodiment of the present invention. The workpiece processing apparatus S includes a plasma generating unit PU (plasma generating apparatus) that generates plasma and irradiates the workpiece W as a workpiece with the plasma, and a predetermined route that passes the workpiece W through the plasma irradiation region. It is comprised from the conveyance means C conveyed by. 2 is a perspective view of the plasma generation unit PU in which the line-of-sight direction is different from that in FIG. 1, and FIG. 3 is a partially transparent side view. 1 to 3, the XX direction is the front-rear direction, the Y-Y direction is the left-right direction, the ZZ direction is the up-down direction, the -X direction is the front direction, the + X direction is the rear direction,- Y will be described as a left direction, + Y direction as a right direction, -Z direction as a downward direction, and + Z direction as an upward direction.

  The plasma generation unit PU is a unit capable of generating plasma at normal temperature and pressure using microwaves. In general, the waveguide 10 propagates microwaves, and one end side of the waveguide 10 ( Microwave generator 20 arranged on the left side to generate microwaves of a predetermined wavelength, plasma generator 30 provided on waveguide 10, and arranged on the other end side (right side) of waveguide 10 to reflect microwaves The sliding short 40 to be performed, the circulator 50 for separating the reflected microwaves from the microwaves emitted to the waveguide 10 so as not to return to the microwave generator 20, and the dummy load 60 for absorbing the reflected microwaves separated by the circulator 50. In addition, a stub tuner 70 for matching impedance between the waveguide 10 and the plasma generation nozzle 31 is provided. The conveying means C includes a conveying roller 80 that is rotationally driven by a driving means (not shown). In the present embodiment, an example in which a flat workpiece W is conveyed by the conveying means C is shown.

  The waveguide 10 is made of a nonmagnetic metal such as aluminum, has a long tubular shape with a rectangular cross section, and propagates the microwave generated by the microwave generator 20 toward the plasma generator 30 in the longitudinal direction thereof. Is. The waveguide 10 is composed of a connected body in which a plurality of divided waveguide pieces are connected to each other by flange portions, and the first conductor on which the microwave generator 20 is mounted in order from one end side. The wave tube piece 11, the second waveguide piece 12 to which the stub tuner 70 is assembled, and the third waveguide piece 13 provided with the plasma generator 30 are connected. A circulator 50 is interposed between the first waveguide piece 11 and the second waveguide piece 12, and a sliding short 40 is connected to the other end side of the third waveguide piece 13.

  The first waveguide piece 11, the second waveguide piece 12, and the third waveguide piece 13 are each formed into a rectangular tube shape using an upper plate, a lower plate, and two side plates made of a metal flat plate. It is assembled and flange plates are attached to both ends thereof. In addition, you may make it use the rectangular waveguide piece formed by extrusion molding, the bending process of a plate-shaped member, etc., or a non-dividing type | mold waveguide irrespective of the assembly of such a flat plate. In addition, the waveguide is not limited to a rectangular cross section, and for example, a waveguide having an elliptical cross section can be used. Furthermore, not only a nonmagnetic metal but a waveguide can be comprised with the various members which have a waveguide effect | action.

  The microwave generator 20 includes, for example, an apparatus main body portion 21 including a microwave generation source such as a magnetron that generates a microwave of 2.45 GHz, and the microwave generated by the apparatus main body portion 21 inside the waveguide 10. And a microwave transmission antenna 22 that emits light to the outside. In the plasma generation unit PU according to the present embodiment, for example, a continuously variable microwave generator 20 that can output microwave energy of 1 W to 3 kW is preferably used.

  As shown in FIG. 3, the microwave generation device 20 has a configuration in which a microwave transmission antenna 22 protrudes from the device main body 21, and is fixed in a mode of being placed on the first waveguide piece 11. Has been. Specifically, the apparatus main body 21 is placed on the upper surface plate 11U of the first waveguide piece 11, and the microwave transmitting antenna 22 is inside the first waveguide piece 11 through the through hole 111 formed in the upper surface plate 11U. The waveguide space 110 is fixed so as to protrude. With this configuration, the microwave of 2.45 GHz, for example, emitted from the microwave transmission antenna 22 is directed from one end side (left side) to the other end side (right side) by the waveguide 10. Propagated.

The plasma generation unit 30 includes eight plasma generation nozzles 31 that are arranged in a row in the left-right direction on the lower surface plate 13B of the third waveguide piece 13 (the surface facing the workpiece to be processed). Configured. The width of the plasma generation unit 30, that is, the arrangement width in the left-right direction of the eight plasma generation nozzles 31 is a width that substantially matches the size t in the width direction orthogonal to the conveying direction of the flat workpiece W. Thereby, the plasma processing can be performed on the entire surface of the workpiece W (the surface facing the lower surface plate 13B) while the workpiece W is being conveyed by the conveying roller 80. The arrangement interval of the eight plasma generating nozzles 31 is preferably determined according to the wavelength lambda _G of the microwave propagating through the waveguide 10. For example, it is desirable to arrange the plasma generating nozzles 31 at a ½ pitch and a ¼ pitch of the wavelength λ _{G. When} a microwave of 2.45 GHz is used, since λ _G = 230 mm, 115 mm (λ _G / 2) The plasma generating nozzles 31 may be arranged at a pitch or 57.5 mm (λ _G / 4) pitch.

  4 is an enlarged side view showing two plasma generation nozzles 31 (one plasma generation nozzle 31 is drawn as an exploded view), and FIG. 5 is a cross-sectional view taken along line AA in FIG. The plasma generating nozzle 31 includes a central conductor 32 (inner conductor), a nozzle body 33 (outer conductor), a nozzle holder 34, a seal member 35, and a protective tube 36.

  The central conductor 32 is made of a highly conductive metal such as copper, aluminum, or brass, and is made of a rod-like member having a diameter of about 1 to 5 mm. While penetrating and projecting into the waveguide space 130 by a predetermined length (this projecting portion is referred to as a receiving antenna portion 320), the lower end portion 322 extends in the vertical direction within the nozzle body 33, and the tip surface 3221 thereof is the nozzle body 33. It is arrange | positioned so that it may become substantially flush with the front end surface 331 of this. Microwave energy (microwave power) is applied to the central conductor 32 when the receiving antenna unit 320 receives the microwave propagating through the waveguide 10. The central conductor 32 is held by a seal member 35 at a substantially intermediate portion in the length direction.

  The nozzle body 33 is a cylindrical body made of a highly conductive metal and having a cylindrical space 332 that houses the central conductor 32. The nozzle holder 34 is also made of a highly conductive metal, and has a relatively large-diameter lower holding space 341 that holds the nozzle body 33 and a relatively small-diameter upper holding space 342 that holds the seal member 35. It is a state. On the other hand, the seal member 35 is made of a heat-resistant resin material such as Teflon (registered trademark) or an insulating member such as ceramic, and has a holding hole 351 for holding the central conductor 32 fixedly on its central axis. It consists of a body.

  The nozzle body 33 is provided in an annularly projecting manner from the upper side, an upper body part 33U fitted in the lower holding space 341 of the nozzle holder 34, an annular recess 33S for holding a gas seal ring 37 described later. A flange portion 33F and a lower body portion 33B protruding from the nozzle holder 34 are provided. In addition, a communication hole 333 for supplying a predetermined processing gas to the cylindrical space 332 is formed in the upper body portion 33U.

  The nozzle body 33 functions as an outer conductor disposed around the central conductor 32, and the central conductor 32 is a cylindrical space with a predetermined annular space H (insulation interval) secured around it. It is inserted on the central axis of 332. The nozzle body 33 has a nozzle holder such that the outer peripheral portion of the upper body portion 33U is in contact with the inner peripheral wall of the lower holding space 341 of the nozzle holder 34 and the upper end surface of the flange portion 33F is in contact with the lower end edge 343 of the nozzle holder 34. 34 is fitted. The nozzle body 33 is preferably attached to the nozzle holder 34 with a detachable fixing structure using, for example, a plunger or a set screw.

  The nozzle holder 34 includes an upper body portion 34U (corresponding approximately to the position of the upper holding space 342) and a lower surface plate 13B that are closely fitted in a through hole 131 formed in the lower surface plate 13B of the third waveguide piece 13. And a lower body portion 34B (substantially corresponding to the position of the lower holding space 341). A gas supply hole 344 for supplying a processing gas to the annular space H is formed in the outer periphery of the lower body portion 34B. Although not shown, a pipe joint or the like for connecting a terminal portion of a gas supply pipe for supplying a predetermined processing gas is attached to the gas supply hole 344. The gas supply hole 344 and the communication hole 333 of the nozzle body 33 are set so that they are in communication with each other when the nozzle body 33 is fitted into the nozzle holder 34 at a fixed position. A gas seal ring 37 is interposed between the nozzle body 33 and the nozzle holder 34 in order to suppress gas leakage from the abutting portion between the gas supply hole 344 and the communication hole 333.

  A plurality of the gas supply holes 344 and the communication holes 333 may be perforated at equal intervals in the circumferential direction, and are not perforated in the radial direction toward the center. The gas may be perforated in the tangential direction of the outer peripheral surface of the cylindrical space 332 so as to swirl the gas. Further, the gas supply hole 344 and the communication hole 333 are not perpendicular to the central conductor 32, and may be formed obliquely from the upper end 321 side to the lower end 322 side in order to improve the flow of the processing gas. Good.

  The seal member 35 has a lower end edge 352 in contact with an upper end edge 334 of the nozzle body 33 and an upper end edge 353 in contact with an upper end locking portion 345 of the nozzle holder 34 in the upper holding space 342 of the nozzle holder 34. Is retained. That is, the upper holding space 342 is assembled so that the seal member 35 supporting the central conductor 32 is fitted and the lower end edge 352 of the nozzle body 33 is pressed by the upper end edge 334. is there.

  As a result of the plasma generation nozzle 31 being configured as described above, the nozzle body 33, the nozzle holder 34, and the third waveguide piece 13 (waveguide 10) are in a conductive state (the same potential), Since the central conductor 32 is supported by the insulating seal member 35, it is electrically insulated from these members. Therefore, as shown in FIG. 6, when the microwave is received by the receiving antenna unit 320 of the central conductor 32 and the microwave power is supplied to the central conductor 32 in a state where the waveguide 10 is at the ground potential. The electric field concentration portion is formed in the vicinity of the tip surface 3221 and the tip surface 331 of the nozzle body 33.

  In this state, when an oxygen-based processing gas such as oxygen gas or air is supplied from the gas supply hole 344 to the annular space H, the processing gas is excited by the microwave power and the tip of the central conductor 32 is excited. Plasma (ionized gas) is generated in the vicinity of the surface 3221. Although this plasma has an electron temperature of tens of thousands of degrees, the gas temperature is a reactive plasma that is close to the outside temperature (a plasma in which the electron temperature indicated by electrons is extremely high compared to the gas temperature indicated by neutral molecules). It is a plasma generated under normal pressure.

  The processing gas thus converted into plasma is radiated as a plume P from the cylindrical space 332 that is a blow-out port by the gas flow supplied from the gas supply hole 344. This plume P contains radicals. For example, when an oxygen-based gas is used as the processing gas, oxygen radicals are generated, and the plume P having an organic substance decomposition / removal action, a resist removal action, and the like can be obtained. In the plasma generation unit PU according to the present embodiment, since a plurality of plasma generation nozzles 31 are arranged, it is possible to generate a line-shaped plume P extending in the left-right direction.

  Incidentally, when an inert gas such as argon gas or nitrogen gas is used as the processing gas, the surface cleaning and surface modification of various substrates can be performed. Further, if a compound gas containing fluorine is used, the substrate surface can be modified to a water-repellent surface, and using a compound gas containing a hydrophilic group can modify the substrate surface to a hydrophilic surface. Furthermore, if a compound gas containing a metal element is used, a metal thin film layer can be formed on the substrate.

  The sliding short 40 has a third waveguide for optimizing the coupling state between the central conductor 32 provided in each plasma generation nozzle 31 and the microwave propagating through the waveguide 10. It is connected to the right end portion of the piece 13, and the standing wave pattern can be adjusted by changing the reflection position of the microwave by displacing the reflection block 42. Therefore, when a standing wave is not used, a dummy load having a radio wave absorption function is attached instead of the sliding short 40.

  The circulator 50 is composed of, for example, a waveguide-type three-port circulator with a built-in ferrite column. Of the microwaves once propagated toward the plasma generator 30, the plasma generator 30 returns without being consumed. The incoming reflected microwave is directed to the dummy load 60 without returning to the microwave generator 20. By arranging such a circulator 50, the microwave generator 20 is prevented from being overheated by the reflected microwave.

  The dummy load 60 is a water-cooled (or air-cooled) radio wave absorber that absorbs the reflected microwave and converts it into heat. The dummy load 60 is provided with a cooling water circulation port 61 for circulating cooling water therein so that heat generated by heat conversion of the reflected microwaves is exchanged with the cooling water. It has become.

  The stub tuner 70 is for impedance matching between the waveguide 10 and the plasma generation nozzle 31, and has three stub tuners arranged in series on the upper surface plate 12 U of the second waveguide piece 12 at a predetermined interval. Units 70A to 70C are provided. The three stub tuner units 70 </ b> A to 70 </ b> C have the same structure, and as shown in FIG. 3, the stub 71 projecting into the waveguide space 120 of the second waveguide piece 12 is moved up and down in the vertical direction. The power consumption by the conductor 32 is maximized, that is, the reflected microwave is minimized, so that plasma ignition is easily generated.

  The conveyance means C includes a plurality of conveyance rollers 80 arranged along a predetermined conveyance path, and the conveyance roller 80 is driven by a driving means (not shown), so that the workpiece W to be processed is generated by the plasma generation. It is conveyed via the section 30. Here, examples of the workpiece W to be processed include a flat substrate such as a plasma display panel and a semiconductor substrate, a circuit substrate on which electronic components are mounted, and the like. In addition, parts and assembled parts that are not flat-shaped can be processed. In this case, a belt conveyor or the like may be employed instead of the conveying roller 80.

  In the workpiece processing apparatus S configured as described above, it should be noted that in the present embodiment, the plasma generating nozzle that can generate plasma at room temperature and normal pressure by being configured as described above. In FIG. 31, the cylindrical space 332 that is the outlet is provided with a protective tube 36 that is a cylindrical dielectric. The protective tube 36 is made of a quartz glass pipe having a predetermined length, has an outer diameter substantially equal to the inner diameter of the cylindrical space 332, and is inserted into the cylindrical space 332.

  First, the front end surface 3221 of the central conductor 32 is disposed in a state where it is flush with or inward of the front end surface 331 of the nozzle main body 33 so as to obtain good ignitability, and the protective tube 36 is provided. In order to prevent arc discharge (abnormal discharge) depicting an arc as indicated by reference symbol ARC in FIG. 5 between the concentric central conductor 32 and the tip surfaces 3221 and 331 of the nozzle body 33, the tip It is arranged so as to protrude in the axial direction from at least one of the surfaces 3221 and 331. In the example of FIG. 5, the distal end surfaces 3221 and 331 are flush with each other, and the distal end surface 361 of the protective tube 36 is disposed so as to protrude by a height D therefrom.

  On the other hand, in FIG. 7, the front end surface 331 of the nozzle body 33 and the front end surface 361 of the protective tube 36 are flush with each other, and the front end surface 3221 of the central conductor 32 recedes by a height D, that is, In this example, the front end surface 361 of the protective tube 36 is disposed so as to protrude from the front end surface 3221 of the central conductor 32. In the present invention, not limited to the examples of FIGS. 5 and 7, the distal end surface 3221 of the central conductor 32 is in a state where the distal end surface 331 of the nozzle body 33 is set back or flush with the distal end surface 331 of the nozzle body 33, and The tip surface 361 is disposed so as to protrude in the axial direction from at least one of the concentric central conductor 32 and the tip surfaces 3221 and 331 of the nozzle body 33 so that arc discharge (abnormal discharge) is suppressed. It only has to be.

  With such a configuration, it is possible to obtain good ignitability, to suppress the occurrence of inadvertent arc discharge, and to stably continue glow discharge, that is, plasma generation. Moreover, the effect which suppresses the said arc discharge (abnormal discharge) is high and it is suitable for the said protrusion height D to be 1 mm or more. Furthermore, it is preferable to use the protective tube 36 made of the quartz glass pipe as a dielectric because the corrosion resistance against plasma is increased. In addition, as the dielectric, ceramic, Teflon (registered trademark), or the like can be used.

  Next, an electrical configuration of the work processing apparatus S according to the present embodiment will be described. FIG. 8 is a block diagram showing a control system of the work processing apparatus S. This control system includes a CPU (central processing unit) 901 and its peripheral circuits, and the like. The overall control unit 90 as a control means, a microwave output control unit 91 including an output interface, a drive circuit, and the like, a gas flow rate control. Unit 92, a conveyance control unit 93, a display unit, an operation panel, and the like, an operation unit 95 for supplying a predetermined operation signal to the overall control unit 90, and a sensor including an input interface, an analog / digital converter, and the like. The input unit 97 includes a sensor 971, a drive motor 931, and a flow rate control valve 923.

  The microwave output control unit 91 performs ON / OFF control and output intensity control of the microwave output from the microwave generator 20. The microwave output controller 91 generates the 2.45 GHz pulse signal and The operation control of the microwave generation by the apparatus main body 21 is performed.

  The gas flow rate control unit 92 controls the flow rate of the processing gas supplied to each plasma generation nozzle 31 of the plasma generation unit 30. Specifically, the opening degree of the flow rate control valve 923 provided in the gas supply pipe 922 connecting the processing gas supply source 921 such as a gas cylinder and each plasma generating nozzle 31 is adjusted.

  The conveyance control unit 93 controls the operation of the drive motor 931 that rotationally drives the conveyance roller 80, and controls the start / stop of conveyance of the workpiece W, the conveyance speed, and the like.

  The overall control unit 90 is responsible for overall operation control of the workpiece processing apparatus S, and transports the workpiece W by the speed sensor 971 input from the sensor input unit 97 in response to an operation signal given from the operation unit 95. The speed measurement result and the like are monitored, and the operation of the microwave output control unit 91, the gas flow rate control unit 92, and the transfer control unit 93 is controlled based on a predetermined sequence.

  Specifically, the CPU 901 starts the conveyance of the workpiece W based on a control program stored in advance in the memory 902, guides the workpiece W to the plasma generation unit 30, and generates a processing gas having a predetermined flow rate for each plasma. Plasma (plume P) is generated by supplying microwave power while being supplied to the nozzle 31, and the plume P is radiated on the surface of the workpiece W while it is being conveyed. Thereby, the some workpiece | work W can be processed continuously.

  According to the workpiece processing apparatus S described above, the workpiece W is transported by the workpiece transport means C, and the plasmaized gas from the plasma generating nozzles 31 arranged and attached to the waveguide 10 is supplied to the workpiece W. Since it can radiate | emit with respect to a workpiece | work, a plasma processing can be continuously performed with respect to several to-be-processed workpiece | work, and a plasma processing can be efficiently performed also with respect to a large-area workpiece. Therefore, it is possible to provide the work processing apparatus S or the plasma generation apparatus PU that is superior in plasma processing workability to various types of workpieces as compared with batch processing type work processing apparatuses. Moreover, since plasma can be generated at an external temperature and pressure, a vacuum chamber or the like is not required, and the equipment configuration can be simplified.

  Further, the microwave generated from the microwave generator 20 is propagated to each of the plurality of plasma generation nozzles 31 via the waveguide 10 and received by the central conductor 32 provided for each of them to be used for plasma generation. The transmission system of the energy held by the microwaves to each plasma generating nozzle 31 can be simplified, and the apparatus configuration can be simplified and the cost can be reduced. Further, when a plurality of plasma generating nozzles 31 are used, as described above, arcing (abnormal discharge) can be prevented and each plasma generating nozzle 31 can generate stable plasma, and the waveguide 10 is used. In this case, the plasma generating nozzle 31 that does not cause undesired reflection due to the arcing (abnormal discharge) can be used particularly preferably.

  Further, since the plasma generation unit 30 in which the plurality of plasma generation nozzles 31 are arranged in a line has a width that substantially matches the size t in the width direction orthogonal to the conveyance direction of the flat workpiece W, By simply passing the workpiece W through the plasma generating unit 30 only once by the conveying means C, the processing of the entire surface can be completed, and the plasma processing efficiency for the plate-shaped workpiece can be remarkably improved. In addition, plasmaized gas can be radiated to the workpiece W being conveyed at the same timing, and uniform surface treatment or the like can be performed.

The work processing apparatus S according to the embodiment of the present invention has been described above, but the present invention is not limited to this, and for example, the following embodiment can be taken.
(1) In the above embodiment, an example in which a plurality of plasma generating nozzles 31 are arranged in a line is shown. However, the nozzle arrangement may be appropriately determined according to the shape of the workpiece W, the power of microwave power, and the like. The plurality of rows of plasma generating nozzles 31 may be arranged in a matrix or in a staggered arrangement in the conveyance direction of the workpiece W.
(2) In the above-described embodiment, the transport unit C that transports the workpiece W is used as the moving unit. As the transport unit C, a mode in which the workpiece W is mounted on the upper surface of the transport roller 80 and transported is exemplified. In addition to this, for example, a form in which the work W is nipped between the upper and lower transport rollers and transported, a form in which the work is stored in a predetermined basket or the like without using the transport roller, and the basket or the like is transported by a line conveyor or the like, or a robot hand For example, the workpiece W may be gripped and conveyed to the plasma generation unit 30 by using a method such as that described above. Alternatively, the moving means may be configured to move the plasma generating nozzle 31 side. That is, the workpiece W and the plasma generation nozzle 31 may be relatively moved on a plane (X, Y plane) intersecting with the plasma irradiation direction (Z direction).
(3) In the above embodiment, a magnetron that generates a microwave of 2.45 GHz is illustrated as a microwave generation source. However, various high-frequency power sources other than the magnetron can be used, and a microwave having a wavelength different from 2.45 GHz. A wave may be used.
(4) In order to measure the microwave power in the waveguide 10, it is desirable to install a power meter at an appropriate position of the waveguide 10. For example, in order to know the ratio of the reflected microwave power to the microwave power emitted from the microwave transmission antenna 22 of the microwave generator 20, a power meter is provided between the circulator 50 and the second waveguide piece 12. It is possible to interpose a waveguide containing the.

  A workpiece processing apparatus and a plasma generation apparatus according to the present invention include an etching processing apparatus and a film forming apparatus for a semiconductor substrate such as a semiconductor wafer, a glass substrate such as a plasma display panel and a cleaning processing apparatus for a printed board, and a sterilization process for medical equipment. The present invention can be suitably applied to an apparatus, a protein decomposition apparatus, and the like.

It is a perspective view which shows the whole structure of the workpiece processing apparatus which concerns on this invention. FIG. 2 is a perspective view of a plasma generation unit with a different line-of-sight direction from FIG. 1. It is a partial see-through | perspective side view of a workpiece | work processing apparatus. It is a side view which expands and shows two plasma generation nozzles (one plasma generation nozzle is drawn as an exploded view). It is the sectional view on the AA line side of FIG. It is the sectional view on the AA line side of FIG. 4 for demonstrating the other arrangement | positioning shape of the protective tube in a plasma generation nozzle. It is a see-through | perspective perspective view which shows the internal structure of a sliding short. It is a block diagram which shows the control system of a workpiece | work processing apparatus.

Explanation of symbols

10 Waveguide 20 Microwave generator (microwave generator)
30 Plasma generating section 31 Plasma generating nozzle 32 Central conductors 3221, 331, 361 Tip surface 33 Nozzle body 34 Nozzle holder 344 Gas supply hole 36 Protective tube 40 Sliding short 50 Circulator 60 Dummy load 70 Stub tuner 80 Transport roller 90 Overall control section 901 CPU
902 Memory 91 Microwave output control unit 92 Gas flow control unit 921 Processing gas supply source 922 Gas supply pipe 923 Flow control valve 93 Transfer control unit 931 Drive motor 95 Operation unit 97 Sensor input unit S Work processing unit PU Plasma generation unit (plasma Generator)
C Conveying means W Workpiece

Claims (5)

Concentric inner and outer conductors, applying a high-frequency pulsed electric field between both electrodes to generate glow discharge and generate plasma between them, processing from the gas supply source In the plasma generation nozzle that radiates the gas to be processed into gas to be processed by supplying gas to the workpiece under normal pressure from the outlet,
A cylindrical dielectric is interposed between the inner conductor and the outer conductor,
The front end surface of the inner conductor is disposed so as to be flush with or inward of the front end surface of the outer conductor, and no arc discharge occurs between the front end surfaces of the inner conductor and the outer conductor. Further, the plasma generating nozzle is characterized in that a tip end surface of the dielectric is arranged to protrude in an axial direction from at least one end surface of the inner conductor and the outer conductor.   The plasma generating nozzle according to claim 1, wherein an amount of the protrusion is 1 mm or more.   3. The plasma generating nozzle according to claim 1, wherein the dielectric is a quartz glass pipe. The microwave generated by the microwave generation means is propagated through the waveguide, and a plurality of plasma generation nozzles according to any one of claims 1 to 3 are provided in the waveguide in the plasma generation unit. Arranged and mounted
The microwave is received by the inner conductor of the plasma generation nozzle, and generates and emits plasma gas from the outer conductor that is grounded through the waveguide. A plasma generator.   5. The plasma generating apparatus according to claim 4, further comprising a moving unit that relatively moves the workpiece and the plasma generating nozzle on a surface intersecting with the plasma irradiation direction, and performing the relative movement while moving the workpiece. A workpiece processing apparatus characterized in that a predetermined process is performed by irradiating a plasma on the workpiece.

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