JP2007207477A - Portable plasma generation system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a plasma generation system which improves supply paths from a plasma generation power supply unit and a gas supply unit, resulting in improvement of workability. <P>SOLUTION: This portable plasma generation system comprises a portable atmospheric pressure plasma generation unit; a plasma generation unit-spectral analysis system consisting of a gas supply unit, a programmable high-frequency power supply unit, a pulse bias power supply unit, and a spectral analysis unit; and a multi-flexible feeder system B for connecting the plasma generation unit-spectral analysis system to the portable atmospheric pressure plasma generation unit. The feeder system B comprises a gas supply line B-2 composed of a PTFE gas introduction pipe B-2a; a fiber optical transmission line B-3 composed of an optical fiber conduit B-3a embedded in an external groove of the external surface of the gas introduction pipe B-2a; a power supply line B-1 composed of a power sleeve B-1b to be externally connected to the gas introduction pipe B-2a, and a ground sleeve B-1a to be externally connected to the power sleeve B-1b via an insulating sleeve B-1c; and a pulse bias voltage application line B-4 composed of a single-wire conductor embedded in the groove of the external surface of the periphery of the gas introduction pipe B-2a. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a portable plasma generation system including a capacitively coupled portable atmospheric pressure plasma generator as a main component, and in particular, from the plasma generation power supply unit and the gas supply unit in order to improve workability. The present invention relates to a portable plasma generation system with an improved supply line section.

  Currently, in the portable plasma generation system, the supply line section between the plasma generator and the plasma generation power supply section and gas supply section is a power supply line section using a cable or the like and a gas supply using a hose or the like, respectively. The line portion is configured in a separate system, and the operability of the plasma generator is deteriorated. In the case where a light receiving means for observing plasma is arranged in the plasma generator, the optical transmission line connecting this and the spectroscopic analyzer is separately configured, which makes it more difficult to handle.

In this regard, there are currently no documents that suggest special improvements.
For example, in any part of Patent Documents 1 to 3 described later, there is a description that any improvement is made to improve workability in the power generation and gas supply lines for generating plasma, or a description that describes the necessity thereof. I can't find it.

Japanese Patent No. 2589599 Japanese Patent No. 3207469 JP 2002-008894 A

  The present invention relates to a portable plasma generation system having a capacitively coupled portable atmospheric pressure plasma generator as a main component, and an improvement of a supply line section from a power supply section or a gas supply section for plasma generation. The problem to be solved is to improve workability.

A first aspect of the present invention includes a capacitively coupled portable atmospheric pressure plasma generator, a plasma generating gas supply unit and a plasma generating power supply unit outside the device, and the portable atmospheric pressure plasma generator. In a portable plasma generation system configured with a gas supply line section and a power supply line section connecting each supply section outside the apparatus,
It is a portable plasma generation system in which the gas supply line unit and the power supply line unit are integrated into a single flexible feeder.

  According to a second aspect of the present invention, in the portable plasma generating system according to the first aspect of the present invention, the portable atmospheric pressure plasma generator is provided with a light receiving means, and a spectroscopic analyzer is provided outside the apparatus, and the feeder is provided with the above-mentioned An optical transmission line portion connecting the light receiving means and the spectroscopic analyzer is integrated and configured.

  According to a third aspect of the present invention, in the portable plasma generation system according to the first aspect of the present invention, the gas supply line section is formed of a flexible pipe material, and the power supply line section is configured to supply high-frequency power. A power sleeve of a mesh-shaped conductor that is sheathed on the outer surface of the mesh sleeve and a grounding sleeve of the mesh-shaped conductor that is sheathed on the power sleeve with an insulating material interposed between them, and an outer periphery of the grounding sleeve that is coated with an insulating material This is a flexible feeder.

  According to a fourth aspect of the present invention, in the portable plasma generation system according to the second aspect of the present invention, the gas supply line section is formed of a flexible pipe material, and the optical transmission line section is provided along the outer circumference of the pipe material along the axial direction. A plurality of optical fiber conduits embedded in the grooves formed in this way, and further, the power supply line section is provided with a mesh-shaped power sleeve sheathed on the tube material for supplying high-frequency power, and an insulating material on the power sleeve. And a single flexible feeder in which the outer periphery of the ground sleeve is integrally covered with an insulating material.

  5 of the present invention is the portable plasma generation system according to 3 or 4 of the present invention, wherein the power supply line section includes an insulating material disposed between and outside the power sleeve and the ground sleeve or the gas supply. A single line conductor for applying a pulse bias voltage embedded in any part of the line portion is added.

  6 of the present invention is the portable plasma generation system according to 3 or 4 of the present invention, wherein the pulse is embedded in the power supply line section in a groove formed along the axial direction on the outer periphery of the tube material. A single-wire conductor for applying a bias voltage is added.

  According to the seventh aspect of the present invention, in the portable plasma generation system according to the third or fourth aspect of the present invention, the power sleeve of the power supply line section is interlocked to switch between supply of high-frequency power for plasma generation and application of a pulse bias voltage. The relay is also used as a conductor for applying a pulse bias voltage, on the premise that the insertion position of the relay is a position close to the high frequency power supply side of the plasma generation power supply unit.

  A seventh aspect of the present invention is the portable plasma generation system according to the third, fourth, fifth, sixth or seventh aspect of the present invention, wherein the tube material is constituted by a PTFE (polytetrafluoroethylene) tube.

  According to one portable plasma generation system of the present invention, a gas supply line unit and a power supply line unit that connect the portable atmospheric pressure plasma generator and each supply unit outside the device are integrated into a single unit. Since it is configured as a flexible feeder, it is easier to arrange them so as not to get in the way compared to the case where they are in separate systems, and workability is improved when the portable atmospheric pressure plasma generator is operated.

  According to the portable plasma generating system of the second aspect of the present invention, the optical transmission line portion connecting the light receiving means arranged in the portable atmospheric pressure plasma generating device and the spectroscopic analyzer outside the device is also integrated with the feeder. Therefore, compared with the case where they are in separate systems, they are easier to organize and workability is improved when operating the portable atmospheric pressure plasma generator.

  According to the portable plasma generating system 3 of the present invention, the gas supply line section and the power supply line section can be reasonably integrated, and a flexible feeder that can be handled easily can be obtained.

  According to the portable plasma generating system 4 of the present invention, the gas supply line unit, the power supply line unit, and the optical transmission line unit can be reasonably integrated, and the flexible feeder is easy to handle. be able to.

  According to the portable plasma generating system of the fifth aspect of the present invention, a single-wire conductor for further applying a pulse bias voltage to any part of a feeder in which the gas supply line section and the power supply line section are integrated. As a result, the workability can be improved when the portable atmospheric pressure plasma generator is operated.

  According to the portable plasma generation system of 6 of the present invention, a single wire conductor for further applying a pulse bias voltage to the feeder in which the gas supply line section and the power supply line section are integrated is also rational. A flexible feeder that is integrated and easy to handle can be obtained.

  According to the portable plasma generating system 7 of the present invention, the power sleeve for supplying high-frequency power can be used also as a conductor for applying a pulse bias voltage, so that a single-wire conductor can be incorporated into the feeder. There is an advantage that the manufacturing process is simplified and the cost can be reduced. This is effective when the line-to-line capacity of the power supply line section for supplying high-frequency power is small, or when the length of the feeder does not exceed several meters, and when these conditions are not met, the pulse waveform is Therefore, it is appropriate to employ 5 of the present invention in which a single-line conductor for applying a pulse bias voltage is embedded in a groove formed along the axial direction on the outer circumference of the tube material. .

  According to the portable plasma generation system of the present invention, the intended feeder can be easily configured by configuring the tube material with a PTFE tube.

  FIG. 1 is an explanatory view showing a portable plasma generation system of the present invention. This system can be broadly divided into equipment for generating plasma, spectroscopic analysis system A, multi-flexible feeder system B, and plasma generation-light detection system (portable atmospheric pressure plasma generator) C as viewed from the upstream side of the gas flow. it can.

  As shown in FIG. 1, the plasma generating device / spectral analysis system A includes a programmable high frequency power supply unit A-1, a pulse bias power supply unit A-2, and a spectroscopic analysis unit A. -3, a gas supply part A-4 which is a supply part of plasma generating gases, and a personal computer (hereinafter abbreviated as PC) part A-5.

  As the programmable high-frequency power supply unit A-1, one capable of generating a bursty voltage waveform in which a carrier wave is intermittent as shown in FIG. This is a power source for discharge and controls the plasma density, space potential and electron temperature. As described above, the waveform has a burst shape in which the carrier wave is intermittent. From the above viewpoint, the amplitude, the carrier frequency, the repetition frequency, and the duty ratio can be appropriately controlled. For example, those capable of controlling these in a range of 0 to 2 kV, 1 to 20 MHz, 1 kHz to 100 kHz, and 5 to 95% are suitable. The repetition frequency is the reciprocal of the total time of the on time and off time of the carrier wave, and the duty ratio is a percentage of the on time with respect to the total time.

  The pulse bias power supply unit A-2 controls the bias voltage and thereby controls the ion bombardment energy, and the power electrode 3 and the conductor of the discharge unit C-1 described later in the portable atmospheric pressure plasma generator C A pulse voltage is applied between the object to be processed and the former having a high voltage and the latter having a low voltage. The output waveform is suitably configured so that it can be controlled in the range of amplitude 0 to 6 kV, pulse width 0 to 100 μs, and repetition frequency 1 kHz to 100 kHz for the above purpose.

  As the spectroscopic analysis unit A-3, for example, a unit having 1024 diffraction gratings and a CCD array 1024ch and having an exposure time in the range of 40 ms to 20 s can be adopted.

  The gas supply unit A-4 can be composed of, for example, a gas cylinder, a valve disposed in the opening thereof, and a controller that controls the valve. The gas cylinder should be determined in relation to the portable atmospheric pressure plasma generator C. In relation to the planned gas cylinder, for example, the gas cylinder has a size within 350, 80, and 80 mm and has a gas pressure resistance of 20 MPa. The thing used by specification can be adopted. The pressure reducing valve attached to the gas cylinder is provided with pressure sensors on the primary side and the secondary side, and it is appropriate that each pressure value can be monitored successively by the PC section A-5. Also, as the valve, for example, a piezo-type valve is adopted, a mass flow controller is incorporated as a controller, and the valve opening and closing and the gas flow range of 0.05 to 5 l / min (1 atm, 0 ° C) are controlled by the PC section A-5. It can be so. Of course, these are determined in relation to the planned portable atmospheric pressure plasma generator C.

  The gas filled in the gas cylinder is helium or the like as the inert gas, and oxygen or methane or the like as the reactive gas.

  As the PC unit A-5, for example, a general one having a performance of CPU: PENTIUM (registered trademark) 4-3 GHz and memory: 512 MB or more can be adopted. It is appropriate that each part in the plasma generation apparatus / spectral analysis system A is incorporated into a single box. For example, as shown in FIG. Of each component, only the PC part A-5 is taken out of the box, and the internal component is mutually connected with a communication standard such as USB, RS-232C, GP-IB, etc. It is also possible to control each internal component including 10b.

  The multi-flexible feeder system B includes a power supply line part B-1, a gas supply line part B-2, a fiber light transmission line part B-3, and a pulse bias voltage application line part B-4 for generating plasma. It consists of. As shown in FIG. 2, for example, they are arranged concentrically to form a single flexible line, and considering the convenience of use, the total length is usually within 3 m and the allowable curvature is about 10 cm. Is appropriate.

  The power supply line section B-1 is arranged concentrically with the mesh conductor power sleeve B-1b, like the mesh conductor ground sleeve B-1a, with the former on the outside and the latter on the inside. In addition, the outer periphery thereof is configured to be held by a flexible insulating material, for example, a PTFE tube (insulating sleeve). Each dimension is not limited to a specific one, but the thickness of the insulating material is assumed to be about 0.5 mm, and power to be supplied and a gas introduction pipe B-2a constituting a gas supply line section B-2 to be described later and In consideration of the above relationship, it is appropriate that the inner diameter of the ground sleeve B-1a is 6 mm, the thickness is 0.2 mm, the inner diameter of the power sleeve B-1b is 3.8 mm, and the thickness is 0.2 mm. It is.

  Needless to say, the power sleeve B-1b and the ground sleeve B-1a of the power supply line section B-1 include a power electrode 3 and a ground electrode 4 which will be described later, respectively. Are electrically connected to the programmable high frequency power supply unit A-1 for generating plasma. The auxiliary electrode 4a described later is connected in parallel with the ground electrode 4. The power electrode 3 and the programmable high-frequency power source A-1 are connected via one interlocking relay 10a, as shown in FIG. 3 (b).

  As the gas introduction pipe B-2a constituting the gas supply line section B-2, various pipe materials can be used. For example, a PTFE pipe is adopted, and these are provided inside the power supply line section B-1. And can be arranged closely in a concentric manner. When the power supply line section B-1 is composed of the ground sleeve B-1a, the power sleeve B-1b, and the insulating material between and around the outer periphery as described above, the gas introduction pipe B-2a It is appropriate to arrange in such a manner that it is in close contact with the inner side of the innermost power sleeve B-1b.

  In the multi-flexible feeder system B, the fiber optical transmission line part B-3 is between the power supply line part B-1 and the gas introduction pipe B-2a constituting the gas supply line part B-2 or It can distribute | arrange in any site | part of those outermost peripheral parts. Of the above, the groove disposed between the above-mentioned two uses a groove formed along the length direction on the peripheral side surface of a pipe material such as a PTFE pipe constituting the gas introduction pipe B-2a. This is advantageous because the optical fiber conduits can be arranged and held therein.

  In this case, grooves are arranged on the peripheral side surface of the gas introduction pipe B-2a constituting the gas supply line portion B-2 in the circumferential direction at a constant angular interval and along the length direction. An optical fiber conduit is embedded to form a fiber optical transmission line section B-3. When a PTFE pipe is used as the gas introduction pipe B-2a, as described above, the optical fiber conduit has a room to be arranged as described above, and therefore has a corresponding peripheral wall thickness. Needless to say, it should be. The optical fiber conduit described above is formed as described above after forming a pipe material such as a PTFE pipe in the grooves.

  The pulse bias voltage application line portion B-4 can also be used as the power sleeve B-1b of the power supply line portion B-1. As a result, the manufacturing process can be simplified and the cost can be reduced. However, if the length of the multi-flexible feeder system B is several meters, the line capacity of the power supply line section B-1 will increase, and if this is also used, the pulse waveform will be lost. It should be done. In this case, a single conductor is insulated and coated between the power supply line section B-1 of the multi-flexible feeder system B and the gas introduction pipe B-2a constituting the gas supply line section B-2, or at the end thereof. It can be routed to any part of the outer periphery.

  The single wire conductor is arranged together with the optical fiber conduit in the groove separately formed along the length direction on the peripheral side surface of the gas introduction pipe B-2a, like the fiber optical transmission line section B-3. It is also possible to do. In this case, the conductor is arranged in parallel between these two optical fiber conduits adjacent in the circumferential direction as appropriate. Naturally, this conductor is also embedded in a groove formed on the circumferential side of the tube material forming the gas introduction tube B-2a.

  Needless to say, the pulse bias voltage application line section B-4 is connected to the power electrode 3 and the high voltage side of the pulse bias power supply section A-2 on the other interlocking relay. 10b is connected. The low voltage side of the pulse bias power supply unit A-2 is connected to the object to be processed by a conductive wire separately extended from here. When pulse bias is used in combination, the interlocking relay 10a and the interlocking relay 10b are complementary to the zero voltage interval indicated by the voltage waveforms of the programmable high frequency power supply A-1 and the pulse bias power supply unit A-2. Therefore, the relay drive should be set appropriately so that power can be supplied. In this case, the plasma state is maintained for several μs immediately after the plasma generating carrier wave is stopped. In addition, these interlocking relays 10a and 10b can be comprised with a semiconductor element. The operation of the interlocking relays 10a and 10b can be controlled by the PC unit A-5 as described above.

  Furthermore, the fiber light transmission line part B-3 is connected to the spectroscopic analysis part A-3 so as to transmit light detected by the light detection part C-2 described later for detecting plasma emission.

  The portable atmospheric pressure plasma generator C, which is the plasma generation-light detection system, includes a discharge unit C-1 for generating plasma and a light detection unit C-2 for detecting plasma emission. As shown in FIG. 3 (b), these are arranged in a cylindrical outer insulating tube 8 and a small-diameter inner insulating tube 9 arranged along the axis.

  The discharge section C-1 for generating plasma is composed of a power electrode 3, a movable ground electrode 4, an auxiliary electrode 4a, and a high-speed nozzle for introducing gas. It is attached to the insulating tube 8 and the internal insulating tube 9.

  The power electrode 3 is configured, for example, as an L-shaped central conductor, and as shown in FIG. 3 (b), the axial direction portion 3a is inserted into the internal insulating tube 9, and from the rear end of the central conductor. The vicinity of the outer end of the vertical portion 3b extending in the perpendicular direction is set on the outer insulating tube 8. A locking groove is formed in the outer insulating tube 8 in the axial direction from the rear end, and the vicinity of the outer end of the vertical portion 3b is inserted into the locking groove so as to contact the downstream end thereof. It is appropriate to arrange. In this case, as described above, the inner insulating tube 9 is coaxially fixed and held on the outer insulating tube 8 through the longitudinal portion 3b of the central conductor constituting the power electrode 3 disposed thereon. It will be.

  The outer insulating tube 8 and the inner insulating tube 9 can be made of, for example, quartz glass.

  The movable ground electrode 4 is formed as an annular conductor, and as shown in FIGS. 3 (a) and 3 (b), is externally slidably provided on the outer periphery of the outer insulating tube 8 along its axial direction. . The sliding range of the ground electrode 4 is set so that the power electrode 3 can be moved to the distal end side of the outer insulating tube 8 as much as necessary to avoid a high temperature. For example, the power electrode 3 is configured so as to be reciprocally movable by approximately 10 mm from the vicinity corresponding to the inside and outside of the power electrode 3 to the distal end side of the external insulating tube 8. The configuration for reciprocal movement is free.

  The auxiliary electrode 4a is arranged in parallel with the ground electrode 4 as described above. The auxiliary electrode 4a is formed as an annular conductor, like the ground electrode 4, and is externally fixed to the outer periphery of the distal end of the external insulating tube 8 as shown in FIG. The auxiliary electrode 4a is covered with an insulating jacket 14 fixed to the outer insulating tube 8 on the tip side. The insulating jacket 14 is also preferably made of quartz glass. It is also possible to make the tip of the outer insulating tube 8 thin at the tip of the plasma outlet, and accordingly, make the ring outer diameter of the auxiliary electrode 4a smaller than that of the ground electrode 4.

  The light detection part C-2 for detecting the plasma emission can be composed of a plurality of optical fiber conduits 5, 5... Extending from the rear end to the front end of the outer insulating tube 8. Although it can be arranged over the outer peripheral portion of the outer insulating tube 8, as shown in FIGS. 3 (a) and 3 (b), the outer insulating tube 8 has a configuration in which it is arranged at constant angular intervals in the peripheral thick portion. Is more preferable. At this time, the end portions of the optical fiber conduits 5, 5... The arrangement of the optical fiber conduits 5, 5,... In the peripheral thick portion of the outer insulating tube 8 is performed by embedding the optical fiber conduits 5, 5,. It can be carried out.

  The high-speed nozzle is configured at the rear end of the outer insulating tube 8, that is, at the center of the upstream end. As this high speed nozzle, various supersonic nozzles can be adopted. For example, as shown in FIG. 3 (b), a cylindrical Laval nozzle 1 can be fitted into the rear end of the outer insulating tube 8.

  As shown in FIG. 3B, the distal end of the external insulating tube 8 is in an open state as it is and serves as a plasma gas outlet.

  Therefore, according to the portable plasma generation system of the present invention, as described above, the portable atmospheric pressure plasma generator C, the programmable high-frequency power supply unit A-1 of the plasma generation device / spectral analysis system A, the pulse bias The power supply unit A-2, the spectroscopic analysis unit A-3, and the gas supply unit A-4, which is a supply unit of plasma generating gases, are introduced into the power supply line unit B-1 and the gas supply line unit B-2. Since the tube B-2a, fiber optical transmission line section B-3, and pulse bias voltage application line section B-4 are connected to each other by a single multi-flexible feeder system B, they are separate systems. Compared to the case where the portable atmospheric pressure plasma generator is operated, it is easy to arrange so as not to get in the way, and workability becomes extremely good when the portable atmospheric pressure plasma generator is operated.

  In addition, the portable atmospheric pressure plasma generator in this system uses a programmable high-frequency power supply unit A-1, which has the same specifications as the conventional atmospheric pressure plasma excitation power supply, to apply higher-energy positive ions to the surface of the workpiece. It can also be irradiated.

  By the way, the gas supplied to the portable atmospheric pressure plasma generator C through the multi-flexible feeder system B from the gas supply unit A-4 of the plasma generation apparatus / spectroscopy system A passes through the high-speed nozzle to the discharge unit C-1. It introduce | transduces in the external insulation pipe | tube 8 to comprise at high speed. Thus, even if the gas introduced into the external insulating tube 8 is at a low flow rate, it can be converted into plasma well at the dielectric barrier discharge portion, and the generated plasma is generated at the tip of the external insulating tube 8. It can be drawn out from the outlet longer. In other words, in addition to the ground electrode 4 movably arranged in the middle of the outer periphery of the outer insulating tube 8, an auxiliary electrode 4a is disposed on the outer periphery of the tip, and is output from the programmable high frequency power supply unit A-1 between these and the power electrode. Therefore, the electric field line density near the tip of the outer insulating tube 8 is increased, and the seed plasma from the dielectric barrier discharge portion located upstream is spatially increased. Atmospheric pressure plasma can be drawn out of the outlet.

  In addition, since the optical fiber conduits 5, 5... Are extended to the tip of the outer insulating tube 8, the plasma emission state in the vicinity of the outlet at the tip is detected well, and this is used for generating plasma through the multi-flexible feeder system B. It is transmitted to the spectroscopic analysis unit A-3 of the instrument / spectrometric analysis system A, and the gas excited state in the plasma and the excited state of the surface of the object to be processed are observed, and this observation result data is input to the PC unit A-5. In the PC unit A-5, the observation result data is compared with the reference state data which is the data of the desired gas excitation state, and based on the comparison result, the amplitude, frequency, etc. of the programmable high frequency power supply unit A-1 The output waveform, the mixing ratio of the gas species supplied from the gas supply unit A-4, the flow rate of each gas species, and the like are appropriately controlled to ensure a desired gas excitation state.

  Further, as described above, the ground electrode 4 arranged on the outer periphery of the outer insulating tube 8 is configured to be movable in the axial direction of the outer insulating tube 8 so that the ground electrode 4 can be brought close to the power electrode 3 when the plasma is ignited. It is possible to move and thereby obtain a relatively low discharge start voltage, and by cooling the power electrode 3 by narrowing the nozzle diameter of the high-speed nozzle, the plasma can be stably maintained at a low gas flow rate.

  Thus, according to this portable plasma generation system, as described above, a single multi-flexible unit in which the portable atmospheric pressure plasma generation device C and each part of the plasma generation apparatus / spectrographic analysis system A are integrated. Because they are connected to each other by the feeder system B, workability is extremely good when operating the portable atmospheric pressure plasma generator compared to the case where they are separate systems, and programmable high frequency for plasma generation The power supply A-1 and the gas cylinder of the gas supply unit A-4 can be reduced in size, and a small system including a small portable atmospheric pressure plasma generator can be obtained.

  This embodiment relates to a portable plasma generation system of the present invention, and the outline of the overall configuration is as shown in FIG.

  As shown in FIG. 1, this system is composed of a plasma generating device / spectral analysis system A, a multi-flexible feeder system B, and a portable atmospheric pressure plasma generator C as viewed from the upstream side of the gas flow. Is.

  As shown in FIG. 1, the plasma generating device / spectral analysis system A includes a plasma generating programmable high-frequency power supply unit A-1, a pulse bias power supply unit A-2, a spectral analysis unit A-3, and a gas. It comprises a supply unit A-4 and a PC unit (personal computer unit) A-5.

  The programmable high frequency power supply A-1 generates a burst-like voltage / current waveform as shown in FIG. 4 (a), and its amplitude, carrier frequency, repetition frequency, and duty ratio are 0 to 2 kV, 1 to It is configured to be controllable in the range of 20 MHz, 1 kHz to 100 kHz, and 5 to 95%.

Explaining this in detail, the programmable high-frequency power supply unit A-1 refers to the effective value output as the amplitude, which can be controlled in the range of 0 to 2 kV as described above. The carrier frequency is the reciprocal of the period t shown in FIG. 4A (1), and can be controlled in the range of 1 to 20 MHz as described above. The repetition frequency is the reciprocal of the total time (t _on + t _off ) of the _on time and off time of the carrier shown in (1) of FIG. 4 (a), which is 1 kHz to 100 kHz as described above. It can be controlled in a range. Further, the duty ratio is a 100 fraction [100 t _on / (t _on + t _off )] of the _on time (t _on ) with respect to the total time (t _on + t _off ), which is 5 as described above. Control is possible in the range of ~ 95%.

  In the pulse bias power supply unit A-2, the former has a high voltage between the power electrode 3 of the discharge unit C-1 of the portable atmospheric pressure plasma generator C and the object 7 to be processed, and the latter is Connection is made so as to apply a pulse voltage that is a low voltage. The output waveform is a rectangular wave configured such that it can be controlled in the range of amplitude 0 to 6 kV, pulse width 0 to 100 μs, and repetition frequency 1 kHz to 100 kHz.

  The spectroscopic analysis unit A-3 has a number of diffraction gratings of 1024, a CCD array of 1024ch, and an exposure time ranging from 40 ms to 20 s.

  The gas supply unit A-4 is composed of a gas cylinder, a valve disposed in the opening thereof, and a controller for controlling the valve. The gas cylinder used had an outer shape of 350, 80, and 80 mm and a gas pressure resistance of 20 MPa. The pressure reducing valve attached to the gas cylinder is provided with pressure sensors on the primary side and the secondary side so that each pressure value can be successively monitored by the PC section A-5. In addition, a piezo-type valve is adopted as the valve, and a mass flow controller is incorporated as a controller so that the valve opening and closing and the gas flow range of 0.05 to 5 l / min (1 atm, 0 ° C) can be controlled by the PC section A-5. It is a thing.

  The PC part A-5 adopts a general notebook type CPU having a performance of CPU: PENTIUM (registered trademark) 4-3 GHz, memory: 512 MB or more, and each part of the plasma generating apparatus / spectral analysis system A And connected to the USB communication standard to control other components in the plasma generation apparatus / spectroscopy system A including the interlocking relays 10a and 10b. .

  The multi-flexible feeder system B includes a plasma generation power supply line section B-1, a gas supply line section B-2, a fiber light transmission line section B-3, and a pulse bias voltage application line section B-4. Consists of. As shown in FIG. 2, they were concentrically arranged to form a single flexible line, with a total length of 3 m and an allowable curvature of 10 cm.

  As shown in FIG. 2, the power supply line section B-1 is concentric with a mesh-like power sleeve B-1b as well as a mesh-like ground sleeve B-1a, with the former on the outside and the latter on the inside. The outer periphery and the outer periphery thereof were respectively held by insulating sleeves B-1c and B-1c made of PTFE (polytetrafluoroethylene). The insulation sleeve B-1c has a thickness of 0.5 mm, the ground sleeve B-1a has an inner diameter of 6 mm, its thickness is 0.2 mm, the power sleeve B-1b has an inner diameter of 3.8 mm, and its thickness is 0.2 mm. 2 mm. In any case, the length is 3 m as described above.

  As the gas supply line section B-2, a PTFE gas introduction pipe B-2a is adopted. As shown in FIG. 2, the inside of the power supply line section B-1, that is, a power sleeve having an inner diameter of 3.8 mm. They were placed concentrically with B-1b in such a manner that they were inserted inside. This PTFE gas introduction tube B-2a has an inner diameter of 2 mm and a peripheral side thickness of 0.7 mm.

  The fiber optical transmission line part B-3 is configured with a plurality of grooves along the length direction on the peripheral side surface of the gas introduction pipe B-2a constituting the gas supply line part B-2. The optical fiber conduits B-3a, B-3a,. As shown in FIG. 2, these optical fiber conduits B-3a, B-3a,... Are arranged at a constant angular interval of 45 degrees in the circumferential direction on the peripheral side surface of the gas introduction pipe B-2a by PTFE. It was embedded in the grooves arranged in the direction along the length direction. These optical fiber conduits B-3a, B-3a,... Are molded into the grooves of the array as described above after the PTFE gas introduction pipe B-2a is formed.

  The optical fiber conduit B-3a described above has a diameter of 200 μm and a transmission wavelength of 200-950 nm.

  The pulse bias voltage application line section B-4 is a single conductor, like the fiber light transmission line section B-3, and is on the peripheral side of the gas introduction pipe B-2a constituting the gas supply line section B-2. A pulse bias voltage application line B-4a was formed by embedding it in a groove on the outer surface. In this case, the single-line conductor constituting the pulse bias voltage application line B-4a is arranged in parallel between the two optical fiber conduits B-3a and B-3a adjacent in the circumferential direction. The gas introduction pipe B-2a is molded and then embedded in the groove on the outer peripheral surface thereof.

  The portable atmospheric pressure plasma generator C is composed of a discharge part C-1 for generating plasma and a light detection part C-2 for detecting plasma emission. As shown in FIG. 3 (b), these are arranged in a cylindrical outer insulating tube 8 and a small-diameter inner insulating tube 9 positioned along the axial center thereof.

  The discharge part C-1 is composed of a power electrode 3, a movable ground electrode 4, a fixed auxiliary electrode 4a, and a Laval nozzle 1 for gas introduction, and as described above, these are external insulating tubes. 8 and the inner insulating tube 9.

  In this embodiment, the power electrode 3 is configured as an L-shaped central conductor, and its axial portion 3a is inserted into the internal insulating tube 9 from the rear end as shown in FIG. The vicinity of the outer end of the vertical portion 3b extending in the direction perpendicular to the rear end of the center conductor is set in the outer insulating tube 8. A locking groove is formed in the outer insulating tube 8 from its rear end in the axial direction, and the vicinity of the outer end of the vertical portion 3b is inserted into the locking groove so as to contact the downstream end thereof. It is arranged in. In this embodiment, the inner insulating tube 9 is fixedly held coaxially to the outer insulating tube 8 through the longitudinal portion 3b of the central conductor constituting the power electrode 3 disposed thereon as described above. It is supposed to be done.

  The outer insulating tube 8 and the inner insulating tube 9 are both made of quartz glass, and the outer insulating tube 8 has a straight cylindrical shape, as shown in FIG. Both the upstream end and the downstream end) are open, and the inner insulating tube 9 is closed at the front end (downstream end) and opened at the rear end (upstream end) as shown in FIG. It has a test tube configuration. In this embodiment, the outer diameter of the outer insulating tube 8 is 5.3 mm, the thickness of its peripheral side is 0.65 mm, the outer diameter of the inner insulating tube 9 is 2 mm, and its thickness is 0.2 mm. It is configured to 5 mm.

  The diameter of the L-shaped central conductor constituting the power electrode 3 is 0.5 mm, the length of the axial direction portion 3 a is 10 mm, and the length of the vertical direction portion 3 b is 3 mm.

  As shown in FIGS. 3 (a) and 3 (b), the movable ground electrode 4 is formed as an annular conductor, and is slidably provided on the outer periphery of the outer insulating tube 8 along its axial direction. . The sliding range of the ground electrode 4 is between the vicinity of the portion that substantially matches the inside and outside of the power electrode 3 and the portion on the tip (downstream end) side of the external insulating tube 8 by about 10 mm from the portion. This range is freely movable. The ground electrode 4 was 5 mm wide and 0.2 mm thick.

  The auxiliary electrode 4a is formed as an annular conductor, like the ground electrode 4, and is externally fixed to the outer periphery of the distal end of the external insulating tube 8 as shown in FIG. 8 is covered with an insulating jacket 14 made of quartz glass fixed to the front end side. The auxiliary electrode 4a has a downstream end positioned at a position retracted upstream by 1 mm from the downstream end of the external insulating tube 8. The auxiliary electrode 4a is electrically connected in parallel with the ground electrode 4. The auxiliary electrode 4a has a width of 5 mm and a wall thickness of 0.2 mm, similar to the ground electrode 4.

  As shown in FIGS. 3A and 3B, the light detection unit C-2 for detecting the plasma emission has eight optical fiber conduits 5 extending from the rear end to the front end of the outer insulating tube 8 as shown in FIGS. In addition, the outer insulating tube 8 has a configuration in which the outer insulating tube 8 is arranged at a constant angular interval of 45 degrees in the circumferential direction in the thick portion on the peripheral side. At this time, the distal end portions of the optical fiber conduits 5, 5... Are close to the distal end (downstream end) of the outer insulating tube 8 up to 0.3 mm. The arrangement of the optical fiber conduits 5, 5,... In the peripheral thick portion of the outer insulating tube 8 is performed by embedding the optical fiber conduits 5, 5,. It is what I did.

  Since the optical fiber conduits 5, 5... Are used by extending the optical fiber conduit B-3a constituting the fiber optical transmission line part B-3 as a matter of course, the diameter is 200 μm and the transmission wavelength is 200-950 nm. is there.

  As shown in FIG. 3 (b), the Laval nozzle 1 has a cylindrical outer shape and has a concave lens shape with a vertical cross section, and has a diameter of 0.2 mmφ at the center viewed from the end face direction and a depth (length). ) Is a product having a 0.5 mm nozzle hole. As described above, the outer insulating pipe 8 is concentrically fitted and fixed to the rear end, that is, the upstream end.

  As shown in FIG. 1, an outer shell C-3 having a larger diameter is coupled to the rear end (upstream side end) of the outer insulating pipe 8, and a gas flow switch C is connected to the outer shell C-3. -3a and gas excitation switch C-3b are arranged. The gas flow switch C-3a is a switch that opens and closes an opening / closing valve (not shown) arranged immediately before the Laval nozzle 1, and the gas excitation switch C-3b includes the programmable high-frequency power supply unit A-1 and the pulse bias. This is a switch for turning on / off the power supply unit A-2.

  The configuration of each part of this portable plasma generation system is as described above, but the flexible feeder system B is divided into an upstream plasma generation device / spectroscopy system A and a downstream portable atmospheric pressure plasma as shown below. Connecting to generator C completes the system.

  Thus, the power sleeve B-1b and the ground sleeve B-1a of the power supply line section B-1 respectively connect the power electrode 3, the ground electrode 4 and the auxiliary electrode 4a of the plasma generating discharge section C-1 to the programmable high frequency power supply section. Electrical connection to A-1. The power electrode 3 and the programmable high-frequency power supply unit A-1 are connected via an interlocking relay 10a as shown in FIG. 3 (b). This interlocking relay 10a includes a semiconductor element including the interlocking relay 10b described later.

  The pulse bias voltage application line section B-4 connects the power electrode 3 of the plasma generating discharge section C-1 and the high voltage side of the pulse bias power supply section A-2 via the interlocking relay 10a. The low voltage side of the pulse bias power supply unit A-2 is individually connected to the object to be processed 7 side with a lead wire separately extended from here. When the pulse bias is used together, the one interlocking relay 10a is opened at the time when the carrier wave of the programmable high frequency power supply A-1 is cut off, and at the same time, the other interlocking relay 10b is closed, so that only the pulse voltage is applied to the power electrode 3. Is supplied. In this case, the pulse width is smaller than the pause time of the carrier wave, and the repetition period is made to coincide with that of the burst voltage waveform. Such a pulse bias is applied when ions need to be accelerated and strongly bombarded to the object 7 when it is desired to roughen without excessively heating the surface of the object 7 to be processed. When the programmable high-frequency power source A-1 is configured to include the pulse having a large slew rate that is superimposed on the burst voltage waveform at the timing, the pulse bias power source unit A-2, the pulse bias voltage application line The part B-4 and the interlocking relays 10a and 10b are unnecessary.

  The fiber light transmission line part B-3 is connected at one end to the spectroscopic analysis part A-3, and the other end is extended as it is as a light detection part C-2 for detecting plasma emission.

  The gas supply line section B-2 is connected to the gas supply section A-4 at one end and connected to the upstream side of the Laval nozzle 1 at the other end.

  Next, the mechanism by which a desired gas excitation state is obtained by the above portable plasma generation system will be described with reference to FIGS.

  The gas flow switch C-3a is operated to open the on-off valve immediately before the Laval nozzle 1, and the gas excitation switch C-3b is turned on.

  Thus, helium gas is supplied from the gas cylinder of the gas supply unit A-4, and as shown by an arrow 6 in FIG. 3B, this is introduced up to the Laval nozzle 1 and through the Laval nozzle 1, 0.5 liters per minute. The helium gas is introduced into the central portion of the upstream end of the outer insulating tube 8 at a high speed at (0.5 l / min). At this time, the movable ground electrode 4 is moved to the upstream side so as to approach the axial portion 3a of the L-shaped central conductor as the power electrode 3. Thus, a relatively low discharge start voltage is obtained, and plasma ignition is facilitated with a small power source capacity. The ignited plasma can be maintained in a stable state even at a low gas flow rate by cooling the power electrode 3 by narrowing the nozzle diameter with the Laval nozzle 1.

  At this time, the programmable high frequency power supply unit A-1 has a waveform as shown in (2) of FIG. 4A, that is, a voltage of 2 MHz, a carrier frequency of 2 MHz, an amplitude of 100 V, a repetition frequency of 100 kHz and a duty ratio of 30%. A current waveform is generated and supplied between the power electrode 3, the movable ground electrode 4 and the auxiliary electrode 4a. When this amplitude is increased, the dielectric is between about 800 V and the ground electrode 4 located on the outer periphery of the outer insulating tube 8 and the power electrode 3 in the inner insulating tube 9 as shown in FIG. A body barrier discharge is generated, during which dielectric barrier discharge plasma 13 is generated.

  Next, by further increasing the amplitude of the high-frequency voltage / current output from the programmable high-frequency power supply unit A-1, as shown in FIG. 8 can be pulled out of the tip. Thus, a torch-like plasma 12 is generated as shown in FIG.

  Thereafter, the movable ground electrode 4 is moved away from the axial portion 3a of the L-shaped central conductor, which is the power electrode 3, and is brought closer to the auxiliary electrode 4a. In this way, it is possible to prevent the power electrode 3 from becoming high temperature and generating impurities.

  When plasma is generated by a waveform having a carrier frequency of 2 MHz, an amplitude of 900 V, a repetition frequency of 100 kHz, and a duty ratio of 30%, that is, the waveforms of FIGS. 4 (a)-(2), it is shown in FIGS. 4 (a)-(1). Compared to the case where the waveform is generated with a larger duty ratio, a plasma state having a lower electron temperature is realized.

  In this case, as shown in FIG. 4 (c), the energy necessary for chemical reaction such as ionization of nitrogen gas and dissociation of oxygen gas is specific to atoms and molecules, so oxygen molecules that are components of the atmospheric atmosphere. And nitrogen molecules are less likely to ionize.

  The gas excitation state in the above plasma is detected by the optical fiber conduits 5, 5... Embedded in the extended state up to the tip (downstream end) of the outer insulating tube 8, and this is detected as the fiber of the multi-flexible feeder system B. The light can be guided to the spectroscopic analysis part A-3 via the optical transmission line part B-3 and monitored by this.

  When monitored in this way, as shown in FIG. 4 (d) -2, it can be seen that the excitation spectrum of oxygen molecules having a wavelength of around 800 nm appears more intensely as a light emission phenomenon in the plasma gas.

  When the excited state of the nitrogen molecular gas is required, the programmable high frequency power supply unit A-1 controls the PC unit A-5 to generate a waveform output with a large duty ratio shown in FIGS. 4 (a)-(1). You just have to operate it. As a result, as shown in FIG. 4D, it can be seen that the excitation spectrum of nitrogen molecules having a wavelength of about 200 to 400 nm appears more intensely.

  Thus, the portable atmospheric pressure plasma generator C can control the excitation state of the plasma generation gas within a certain range by controlling the output waveform of the programmable high-frequency power supply unit A-1 according to the purpose.

  According to the above portable plasma generation system, as described above, the portable atmospheric pressure plasma generation device C, the programmable high-frequency power supply unit A-1 of the plasma generation device / spectroscopy analysis system A, pulse bias The power supply unit A-2, the spectroscopic analysis unit A-3, and the gas supply unit A-4, which is a supply unit for plasma generating gases, are each integrated into a single multi-flexible feeder system B with the above-described configuration. Since the power supply line section B-1, the gas supply line section B-2, the fiber optical transmission line section B-3, and the bias voltage application line section B-4 are connected to each other, they become separate systems. Compared with the case where the device is not disturbed, it is flexible and easy to handle, and the workability is extremely good when the portable atmospheric pressure plasma generator is operated.

BRIEF DESCRIPTION OF THE DRAWINGS Explanatory drawing which shows the whole portable plasma generation system of this invention. Cross-sectional explanatory drawing which shows the outline | summary of the multi-flexible feeder of an Example. (a) is a cross-sectional explanatory view showing the plasma discharge structure and fiber light detection function in the main part of the portable atmospheric pressure plasma generator of the embodiment, (b) is the portable atmospheric pressure plasma generator of the embodiment. Side surface explanatory drawing explaining the plasma discharge structure and fiber light detection function which start. (a) is a diagram showing the output waveform of the programmable high-frequency power supply unit when generating plasma using the portable atmospheric pressure plasma generator of the embodiment, (b) is a diagram showing the energy distribution of plasma electrons corresponding to the waveform (C) is a figure which shows an example of the chemical reaction which arises in a plasma, (d) -1 and (d) -2 are figures which show an example of the emission spectrum of the plasma to produce | generate.

Explanation of symbols

A Plasma generator / spectroscopy system
A-1 Programmable high frequency power supply
A-2 Pulse bias power supply
A-3 Spectroscopic analysis unit
A-4 Gas supply unit
A-5 PC section (personal computer) section
B Multi-flexible feeder system
B-1 Power supply line
B-1a Grounding sleeve
B-1b Power sleeve
B-1c Insulation sleeve
B-2 Gas supply line
B-2a Gas introduction pipe
B-3 Fiber optical transmission line
B-3a optical fiber conduit
B-4 Pulse bias voltage application line
B-4a Pulse bias voltage application line
C Portable atmospheric pressure plasma generator
C-1 Discharge part
C-2 Photodetector
C-3 outer shell
C-3a Gas flow switch
C-3b Gas excitation switch 1 Laval nozzle 3 Power electrode 3a Axial direction part 3b Longitudinal part 4 Ground electrode 4a Auxiliary electrode 5 Optical fiber conduit 6 Gas flow arrow 7 Processed object 8 External insulation pipe 9 Internal insulation pipe 10a Programmable high-frequency voltage Interlocking relay for intermittent operation 10b Interlocking relay for intermittent pulse bias voltage 14 Insulation jacket

Claims (8)

Capacitively coupled portable atmospheric pressure plasma generator, plasma generation gas supply unit and plasma generation power supply unit outside the device, the portable atmospheric plasma generator and each supply outside the device In a portable plasma generation system composed of a gas supply line section and a power supply line section connecting the sections,
A portable plasma generation system in which the gas supply line unit and the power supply line unit are integrated into a single flexible feeder.   The portable atmospheric pressure plasma generator is provided with a light receiving means, and a spectroscopic analysis device is provided outside the apparatus, and an optical transmission line unit for connecting the light receiving means and the spectroscopic analysis device is integrated with the feeder. The portable plasma generation system according to claim 1 configured.   The gas supply line section is formed of a flexible pipe, and the power supply line section is provided with a mesh-shaped power sleeve that is sheathed on the pipe for supplying high-frequency power, and the power sleeve is covered with an insulating material. The portable plasma generating system according to claim 1, further comprising a single flexible feeder comprising a grounding sleeve made of a mesh conductor that is coated with an insulating material on an outer periphery of the grounding sleeve.   The gas supply line section is composed of a flexible pipe material, the optical transmission line section is composed of a plurality of optical fiber conduits embedded in grooves formed along the axial direction on the outer periphery of the pipe material, and the power supply line And a mesh-shaped conductor power sleeve sheathed on the pipe material and a mesh-shaped conductor ground sleeve sheathed on the power sleeve with an insulating material for supplying high-frequency power. The portable plasma generation system according to claim 2, wherein the flexible plasma generator is configured as a single flexible feeder that is integrally covered with an insulating material.   A single wire for applying a pulse bias voltage, embedded in the power supply line section, in an insulating material disposed between and outside the power sleeve and the ground sleeve or in any part of the gas supply line section. The portable plasma generation system according to claim 3 or 4, wherein a conductor is added.   The portable plasma according to claim 3 or 4, wherein a single-line conductor for applying a pulse bias voltage, which is embedded in a groove formed along the axial direction on the outer circumference of the tube material, is added to the power supply line portion. Generating system.   Position where the power sleeve of the power supply line section is moved to the high frequency power supply side of the plasma generation power supply section where the interlocking relay that switches between supply of high frequency power for plasma generation and application of pulse bias voltage is moved The portable plasma generation system according to claim 3 or 4, wherein the portable plasma generation system is also used as a conductor for applying a pulse bias voltage.   The portable plasma generation system according to claim 3, 4, 5, 6, or 7, wherein the tube material is a PTFE tube.

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