JP2007188823A - Treatment gas discharging device and surface treatment device equipped with the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a treatment gas discharging device capable of preventing waste of power and heightening cooling efficiency of an inner dielectric through elimination of gaps generated between the inner dielectric and an inner electrode. <P>SOLUTION: The treatment gas discharging device is provided with a tubular outer dielectric 22 having a supply hole 23 and a discharge hole 24, an outer electrode 26 fitted at an outer periphery face of the outer dielectric 22 and grounded, a tubular inner dielectric 35 fitted inside the tube of the outer dielectric 22, an inner electrode 36 comprising a tubular core material 37 fitted inside the tube of the inner dielectric 35 and metal foil 38 wound around its outer periphery face, a high-frequency power source 39 impressing high-frequency voltage between the core material 37 and the outer electrode 26, a gas supply mechanism supplying treatment gas from the supply hole 23 into a space between the outer dielectric 22 and the inner dielectric 35, and a cooling liquid circulation mechanism circulating cooling liquid inside the core material 37. The inner electrode 36 comes in contact with an inner periphery face of the inner dielectric 35 without a gap due to springback of the metal foil 38. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a processing gas discharge device that converts a processing gas into plasma and discharges it, and a surface processing device that includes the processing gas discharge device and processes the surface of a processing object with the processing gas discharged from the processing gas discharge device. .

  As the surface treatment apparatus, conventionally, for example, one disclosed in Japanese Patent Application Laid-Open No. 2003-109799 is known, and this surface treatment apparatus is disposed above a substrate, which is an object to be treated, appropriately supported. And a processing gas discharge device including a discharge mechanism that discharges the processing gas into plasma toward the substrate and a gas supply mechanism that supplies the processing gas to the discharge mechanism.

  The discharge mechanism is formed in a tubular shape, and is provided on the outer peripheral surface of the external dielectric disposed above the substrate. The external electrode is grounded. The discharge mechanism is formed in a tubular shape in the tube of the external dielectric. An internal dielectric provided to be spaced apart from the external dielectric and coaxially with the external dielectric, a rod-shaped internal electrode provided in a tube of the internal dielectric, and between the internal electrode and the external electrode A high frequency power supply for applying a high frequency voltage.

  The external dielectric includes a supply hole that is opened in the upper outer peripheral surface and supplied with a processing gas, and a discharge hole that is opened in the lower outer peripheral surface and discharges the supplied processing gas toward the substrate. A plurality of supply holes and discharge holes are formed at predetermined intervals in the axial direction of the external dielectric.

  The gas supply mechanism includes a supply pipe connected to a supply hole of the external dielectric, and supplies a processing gas from the supply hole to the external dielectric and the internal dielectric via the supply pipe.

  According to this surface treatment apparatus, a processing gas is supplied between the external dielectric and the internal dielectric from the supply hole through the supply pipe by the gas supply mechanism, and between the internal electrode and the external electrode by the high frequency power source. A high frequency voltage is applied to the first electrode, and a high frequency electric field is formed by the internal electrode and the external electrode.

  The processing gas supplied between the external dielectric and the internal dielectric flows between the external dielectric and the internal dielectric toward the discharge hole side, and the internal electrode (internal dielectric) by the high-frequency electric field. ) And an external electrode (external dielectric) to generate plasma containing radical atoms, ions, etc., and are discharged from the discharge hole toward the substrate below the discharge hole. Then, the substrate is processed by the plasmatized processing gas discharged in this manner.

JP 2003-109799 A

  However, in the above conventional surface treatment apparatus, a gap is not generated between the inner peripheral surface of the internal dielectric and the outer peripheral surface of the internal electrode, that is, the outer peripheral surface of the internal electrode is formed on the inner peripheral surface of the internal dielectric. It is difficult to place the internal electrode in the internal dielectric tube in the state of complete contact, and a gap is created between the internal dielectric and the internal electrode, so a discharge is also generated between the internal dielectric and the internal electrode. There was a problem of wasting power and wasting power.

  In addition, as disclosed in Japanese Patent Laid-Open No. 2001-35835, it has been proposed that the internal electrode is composed of a tube body, and the coolant flows through the tube. Even if an internal electrode is applied to the surface treatment apparatus and the internal dielectric is cooled to prevent the internal dielectric from being damaged, a gap is generated between the internal dielectric and the internal electrode as described above. Therefore, the internal dielectric cannot be cooled efficiently. Further, when the temperature of the internal dielectric rises, the discharge concentrates on the portion where the temperature has risen, so that there is a problem that the temperature further increases.

  The present invention has been made in view of the above circumstances, and eliminates a gap generated between the internal dielectric and the internal electrode to prevent wasteful power consumption and cooling efficiency of the internal dielectric. It is an object of the present invention to provide a processing gas discharge device capable of improving the process and a surface treatment apparatus including the processing gas discharge device.

To achieve the above object, the present invention provides:
A processing gas discharge device comprising discharge means for converting a processing gas into plasma and discharging, and gas supply means for supplying the processing gas to the discharge means;
The discharge means is
An external dielectric made of a tubular member and having a supply hole to which the processing gas is supplied and a discharge hole for discharging the supplied processing gas opened on an outer peripheral surface;
An outer electrode provided on the outer peripheral surface of the external dielectric at a position that does not block the supply hole and the discharge hole, and is grounded;
An inner dielectric formed of a tubular member and provided in the outer dielectric tube so as to be spaced apart from the inner peripheral surface of the outer dielectric and coaxially with the outer dielectric;
An internal electrode provided in the internal dielectric tube;
Voltage application means for applying a voltage between the internal electrode and the external electrode,
The gas supply means is configured to supply the processing gas between the external dielectric and the internal dielectric from the supply hole,
The processing gas supplied between the external dielectric and the internal dielectric is turned into plasma by applying a voltage between the internal electrode and the external electrode by the voltage applying means, and then the discharge hole. In the processing gas discharge device configured to be discharged from the outside,
The internal electrode is composed of a sheet-like metal foil wound in a cylindrical shape so that a central axis is parallel to the axis of the internal dielectric, and the metal foil is deformed by applying an external force, and the external force The shape of the metal foil is restored to the original shape by removing the surface of the metal foil, and the shape of the metal foil is configured to abut against the inner peripheral surface of the internal dielectric by a shape restoration action. The present invention relates to a processing gas discharge device.

  According to the processing gas discharge device, when the processing gas is supplied from the supply hole between the external dielectric and the internal dielectric by the gas supply means, the supplied processing gas is supplied to the external dielectric and the internal dielectric. Flows toward the discharge hole.

  A voltage is applied between the internal electrode (metal foil) and the external electrode by a voltage applying means, and an electric field is formed by the internal electrode and the external electrode, and the processing gas passes through the internal electrode by the electric field. Plasma including radical atoms and ions is generated by discharge generated between the (internal dielectric) and the external electrode (external dielectric). The plasma-ized processing gas is discharged from the discharge hole toward the outside.

  In the present invention, the internal electrode is composed of a sheet-like metal foil wound in a cylindrical shape so that the center axis is parallel to the axis of the internal dielectric, and the metal foil is deformed by applying an external force. The shape is restored to the original shape by removing the external force (that is, provided with a springback characteristic), and the surface of the metal foil is brought into contact with the inner peripheral surface of the internal dielectric by the shape restoration action. Since the outer diameter of the wound metal foil is made smaller than the inner diameter of the inner dielectric by an external force and placed in the inner dielectric tube, the outer force is removed. Since the outer diameter is increased by the springback, the internal electrode (metal foil) can be completely brought into contact with the inner peripheral surface of the internal dielectric without generating a gap. As a result, it is possible to prevent discharge from occurring between the internal dielectric and the internal electrode, thereby preventing wasteful power consumption.

  The discharge means further includes a cooling fluid circulation means for circulating a cooling fluid inside the internal electrode, and the internal electrode is disposed in the metal foil and the pipe of the internal dielectric, and is disposed on the outer peripheral surface. The cooling fluid circulating means has a first connecting pipe and a second connecting pipe respectively connected to both ends of the core material, and the cooling fluid is supplied from the first connecting pipe. And the supplied cooling fluid may be recirculated from the second connecting pipe, and the voltage applying means may be configured to apply a voltage between the core material and the external electrode. .

  In this way, a voltage is applied between the core material of the internal electrode and the external electrode by the voltage application means, and an electric field is formed by the metal foil and the external electrode, and also supplied from the cooling fluid circulation means to the core material. The internal dielectric is cooled by the cooling fluid flowing through the pipe. As described above, since the metal foil can be completely brought into contact with the inner peripheral surface of the inner dielectric without causing a gap, the inner dielectric is efficiently and uniformly made by the cooling fluid flowing through the core tube. The cooling can be performed, and the temperature rise of the internal dielectric can be prevented to prevent the internal dielectric from being damaged.

  The discharge means further includes a cooling fluid circulation means for circulating a cooling fluid inside the internal electrode, and the internal electrode is sealed in the pipe of the internal dielectric with the metal foil being sealed at one end. The cooling fluid circulating means includes a cooling pipe in which one end and an outer peripheral face are provided at a distance from the inner face of the core, and a cooling pipe of the cooling pipe. A first connecting pipe connected to the other end; and a second connecting pipe connected between the core and the cooling pipe on the other end of the core, and supplying a cooling fluid from one of the connecting pipes At the same time, the supplied cooling fluid may be recirculated from the other of the connection pipes, and the voltage applying means may be configured to apply a voltage between the core material and the external electrode.

  In this way, the core material and the cooling pipe are configured in a double pipe structure, and each connection pipe is connected to the other end side of the core material and the cooling pipe, so that maintenance can be efficiently performed from one side of the internal dielectric. Can do. In addition, it is not necessary to provide the space for arranging the connecting pipes on both sides of the inner dielectric as in the case where the connecting pipes are connected to both ends of the core material. You can also.

  Moreover, it is preferable that the thickness of the said metal foil is 20 micrometers-50 micrometers. This is because if the thickness is less than 20 μm, it is too thin to cause manufacturing problems and handling problems, and if the thickness is more than 50 μm, the strength is increased and it is difficult to wind the tube. Therefore, if it is in the said range, manufacture can be facilitated and handling can be facilitated, or it can be easily wound in a cylindrical shape.

  Examples of the material of the metal foil include stainless steel, nickel-plated copper, and iron, but are not limited thereto.

The present invention also provides:
Support means for supporting the object to be treated;
Including the processing gas discharge device described above,
The processing gas discharge device is disposed so that the discharge hole faces the processing object supported by the support means,
According to the surface treatment apparatus, the surface of the object to be treated is treated with the treatment gas discharged from the treatment gas discharge apparatus.

  According to this surface treatment apparatus, as described above, the process gas discharge device prevents discharge from occurring between the internal dielectric and the internal electrode, thereby preventing wasteful power consumption, Since the dielectric can be efficiently and uniformly cooled to prevent damage to the internal dielectric, the cost for plasma surface treatment (for example, surface modification treatment, cleaning treatment, film formation treatment, etc.) can be reduced. In addition, the plasma surface treatment can be performed efficiently such as by reducing the number of maintenance.

  As described above, according to the processing gas discharge apparatus according to the present invention, it is possible to prevent wasteful consumption of electric power or to cool the internal dielectric material efficiently and uniformly to prevent them from being damaged. In addition, according to the surface treatment apparatus of the present invention, plasma surface treatment can be performed at low cost, and plasma surface treatment can be efficiently performed such as reducing the number of maintenance.

  Hereinafter, specific embodiments of the present invention will be described with reference to the accompanying drawings. 1 is a front sectional view showing a schematic configuration of a surface treatment apparatus according to an embodiment of the present invention, FIG. 2 is a sectional view in the direction of arrows AA in FIG. These are sectional drawings of the arrow BB direction in FIG. 4 is a plan view showing the schematic configuration of the external dielectric according to the present embodiment, FIG. 5 is a bottom view of the external dielectric shown in FIG. 4, and FIG. 6 is the present embodiment. FIG. 7 is a cross-sectional view illustrating a schematic configuration of the internal electrode and the cooling pipe according to the present embodiment, and FIG. 8 illustrates the schematic configuration of the internal electrode according to the present embodiment. It is the bottom view which showed schematic structure of the connection member and the baffle plate.

  As shown in FIGS. 1 to 3, the surface treatment apparatus 1 of the present example horizontally supports a substrate K as a processing object and conveys the substrate K in a predetermined direction (the direction indicated by the arrows in FIGS. 2 and 3). 10 and a discharge mechanism 21 that is disposed above the substrate K that is transported by the transport roller 10 and that discharges the processing gas into plasma toward the substrate K, and a gas that supplies the processing gas to the discharge mechanism 21 A processing gas discharge device 20 including a supply mechanism 50 is provided.

  A plurality of the transport rollers 10 are arranged at predetermined intervals along the substrate transport direction, and both end portions of the rotation shaft 10a are rotatably supported by support members (not shown). Further, the conveyance roller 10 has one end of a rotary shaft 10a connected to a drive mechanism (not shown), and the drive shaft (not shown) causes the rotary shaft 10a to rotate about the axis, The substrate K is transported in the substrate transport direction.

  The discharge mechanism 21 includes an external dielectric 22 made of a quartz glass tube, an external electrode 26 provided on the outer peripheral surface of the external dielectric 22, and a metal such as aluminum. A holding member 27 for holding 22, a metal such as stainless steel, a trumpet-shaped conductive member 29 provided at both ends of the holding member 27 in the axial direction of the external dielectric 22, a quartz glass tube, and the like, In the tube of the external dielectric 22, an internal dielectric 35 is provided so as to be spaced apart from the inner peripheral surface of the external dielectric 22 and coaxially with the external dielectric 22, and provided in the tube of the internal dielectric 35. The coolant is circulated and circulated through the internal electrode 36, the high-frequency power source 39 that applies a high-frequency voltage between the internal electrode 36 and the external electrode 26, and the internal electrode 36 and the holding member 27. That includes a coolant circulation system 40.

  The external dielectric 22 is provided above the substrate K so that its axis is orthogonal to the substrate transport direction and faces the substrate K at a predetermined interval over the entire width of the substrate K. A convex portion 22a formed on the surface, a flange portion 22b formed on both ends, a supply hole 23 penetrating from the upper surface of the convex portion 22a to the inner peripheral surface and supplied with a processing gas from the gas supply mechanism 50, A discharge hole 24 that penetrates from the lower outer peripheral surface to the inner peripheral surface and discharges the supplied processing gas toward the substrate K is provided.

  The supply hole 23 and the discharge hole 24 are each composed of a plurality of slit holes formed in a line in the axial direction of the external dielectric 22, as shown in FIGS. Slit portions 23a and 24a having predetermined lengths L1 and L4, and round holes 23b formed at both ends of the slit portions 23a and 24a and having diameters D1 and D2 larger than the slit widths L2 and L5 of the slit portions 23a and 24a, 24b (the diameter D1 is larger than the slit width L2 and the diameter D2 is larger than the slit width L5), and the distance between adjacent ends is predetermined so that the longitudinal direction is along the axis of the external dielectric 22 They are formed so as to be spaced L3 and L6.

  The longitudinal lengths L1 and L4 of the slit portions 23a and 24a are set to 300 mm to 1200 mm, the slit width L2 of the slit portion 23a is set to 0.2 mm to 2.0 mm, and the slit holes The distances L3 and L6 between adjacent end portions are set to 0.5 mm to 2.0 mm, the diameter D1 of the round hole 23b is set to 2 to 6 times the slit width L2, and the round hole 24b. The diameter D2 is set to 2 to 6 times the slit width L5.

  The slit width L5 of the slit portion 24a is difficult to be smaller than 0.2 mm due to processing problems, but is preferably as small as possible. This is because the flow width of the processing gas discharged from the discharge hole 24 is increased by narrowing the slit width L5, and the processing gas in the excited state reaches the surface of the substrate K before returning to the normal state. Because you can.

  The external electrode 26 is made of a metal film such as aluminum, and is provided in contact with the outer peripheral surface between the convex portion 22 a and the vicinity of the discharge hole 24 on both the left and right sides of the external dielectric 22. 27 is grounded.

  The holding member 27 is composed of a pair of two symmetrical members each having a cooling flow path 27a for allowing the coolant to flow. The holding member 27 is in contact with the outer peripheral surface of the external electrode 26 so that the external dielectric 22 is left and right. While sandwiching from both sides, the external dielectric 22 is held in a state where both ends protrude from the holding member 27 and the conductive member 29. The left and right holding members 27 are connected and fixed by a connecting member 28 attached to the upper surface thereof.

  The conductive member 29 is attached to both ends of the holding member 27 in the axial direction of the external dielectric 22 (that is, disposed at both ends of the external electrode 26 in the axial direction of the external dielectric 22). A flat mounting portion 30 having a coaxial through hole 30a, and fixed to the surface of the mounting portion 30, are formed in an arc shape with a distance from the outer peripheral surface of the external dielectric 22, and from the mounting portion 30 side. An inclined portion 31 that is inclined at an inclination angle θ with respect to the axis of the external dielectric 22 and is formed coaxially with the external dielectric 22 is provided so that the inner diameter increases as the distance from the axis of the external dielectric 22 increases. Thus, the outer peripheral surface of the external dielectric 22 is surrounded by the conductive member 29 (inclined portion 31) except for the lower portion thereof. The conductive member 29 is configured as a pair of two symmetrical members, and the inclination angle θ is set in a range of 2 ° to 30 °.

  The internal dielectric 35 is disposed inside the external dielectric 22 with its both ends protruding from both ends of the external dielectric 22, and one end is sealed by a sealing member 35a. The inner dielectric 35 is fixed between the inner peripheral surface of the outer dielectric 22 by a spacer (not shown) provided on the inner peripheral surface of the outer dielectric 22 at regular intervals in the axial direction of the outer dielectric 22. The gap is reliably formed and arranged. The gap between the inner dielectric 35 and the outer dielectric 22 is sealed by cylindrical sealing members 32 and 33 provided with one end abutting against the end surface of each flange 22b of the outer dielectric 22. Has been.

  As shown in FIGS. 1 to 3, 6, and 7, the internal electrode 36 is formed of a stainless steel tube or the like having one end sealed with a sealing member 37 a, and the internal dielectric 35 is disposed within the internal dielectric 35. A core material 37 disposed coaxially with the body 35, and a sheet-like member made of stainless steel and having a thickness of 20 μm to 50 μm, and a metal foil 38 wound around the outer peripheral surface of the core material 37 in a cylindrical shape. The metal foil 38 is configured to be deformed when an external force is applied, and to be restored to its original shape when the external force is removed (that is, to have a springback characteristic), and to recover the metal by a shape recovery action. The surface of the foil 38 is configured to contact the inner peripheral surface of the internal dielectric 35.

  As shown in FIG. 6, the core material 37 is inserted into the tube of the inner dielectric 35 after the metal foil 38 is wound so that the outer diameter thereof is smaller than the inner diameter of the inner dielectric 35. When the external force acting on the metal foil 38 is removed by being inserted into the tube of the internal dielectric 35, the outer diameter is increased by the spring back of the metal foil 38. The entire surface is brought into contact with the metal foil 38. Further, the metal foil 38 may be made of nickel-plated copper or iron instead of stainless steel. One end of the core material 37 is located closer to the end of the external dielectric 22 than the external electrode 26, the holding member 27, and the conductive member 29.

  The high frequency power supply 39 is configured to apply a high frequency voltage between the core material 37 of the internal electrode 36 and the external electrode 26.

  As shown in FIGS. 1 to 3, 6, and 7, the coolant circulation mechanism 40 is disposed in the pipe of the core material 37, and one end and an outer peripheral surface of the coolant circulation mechanism 40 are provided at a distance from the inner surface of the core material 37. A metal wire 42 made of a pipe 41 and a stainless steel wire and spirally wound around the outer peripheral surface of the cooling tube 41 to ensure a constant interval between the inner peripheral surface of the core material 37 and the outer peripheral surface of the cooling tube 41. The other end of the core material 37 is connected, and the other end side of the cooling pipe 41 is provided therethrough, the first connection pipe 44 connected to the other end of the cooling pipe 41, and the core material 37 via the joint 43. A second connecting pipe 45 connected between the cooling pipe 41, a third connecting pipe (not shown) connected to one end side of the cooling flow path 27a of the holding member 27, and the other end side of the cooling flow path 27a. A fourth connecting pipe (not shown) connected to the first connecting pipe 44 and the third connecting pipe (see FIG. It supplies a coolant from without), and a circulating device 46 for returning the supplied cooling liquid second connecting pipe 45 and the fourth connecting pipe (not shown).

  As shown in FIG. 1 to FIG. 3 and FIG. 8, the gas supply mechanism 50 is introduced such that one end is sealed and the one end is disposed above the external dielectric 22 and parallel to the axis of the external dielectric 22. A pipe 51 and a processing gas generation device 52 that is connected to the other end of the introduction pipe 51 and includes a pressure swing adsorption (PSA) type nitrogen gas generation device or the like and generates a processing gas mainly containing nitrogen gas; A connecting member 53 having a top end connected to the inside of the pipe from the outer peripheral surface of the lower end on one end side of the introduction pipe 51, and a lower end connected to the upper surface of the protrusion 22 a of the external dielectric 22. A plurality of rectifying plates 54 each including a plurality of through-holes 54a formed of a flat plate-like and elongated member provided to be overlapped with the inside of the upper end side of the connection member 53 and vertically formed and arranged in a line in the longitudinal direction. Equipped with a process gas generator Introducing tube 51 from 52, the connecting member 53 (rectifying plate 54), supplying the process gas between the outer dielectric 22 and the inner dielectric 35 sequentially through the supply holes 23. A concave groove 53a is formed on the lower surface of the connection member 53 so as to surround the periphery of the supply hole 23, and a seal member 55 is disposed in the concave groove 53a. The connection part with the convex part 22a is kept airtight.

  According to the surface treatment apparatus 1 of the present example configured as described above, the process gas generated by the process gas generation device 52 of the gas supply mechanism 50 is supplied via the introduction pipe 51, the connection member 53, and the rectifying plate 54. When supplied between the external dielectric 22 and the internal dielectric 35 from the hole 23, the supplied processing gas flows between the external dielectric 22 and the internal dielectric 35 toward the discharge hole 24 side. To do.

  A high-frequency voltage is applied between the core material 37 of the internal electrode 36 and the external electrode 26 by a high-frequency power supply 39, and a high-frequency electric field is formed by the metal foil 38 (internal electrode 36) and the external electrode 26. The gas is turned into plasma containing radical atoms, ions, and the like by discharge generated between the metal foil 38 (internal dielectric 35) and the external electrode 26 (external dielectric 22) by the high-frequency electric field.

  Then, the plasma-ized processing gas is discharged to the outside from the discharge hole 24, and the surface of the substrate K transferred by the transfer roller 10 is processed by radical atoms and ions in the discharged processing gas (for example, Surface modification treatment, cleaning treatment, film formation treatment, etc. are performed).

  The holding member 27, the external electrode 26, the core material 37 of the internal electrode 36, and the metal foil 38 are supplied from the circulation device 46 of the coolant circulation mechanism 40, and the inside of the cooling channel 27 a, the core material 37, the cooling pipe 41, and the like. The quartz glass tube which is the outer dielectric 22 and the inner dielectric 35 is prevented from being broken by this.

  Further, the flow rate of the processing gas supplied from the supply hole 23 between the external dielectric 22 and the internal dielectric 35 is made uniform by the plurality of rectifying plates 54 provided in the connection member 53 of the gas supply mechanism 50. Thus, the plasma state between the outer dielectric 22 and the inner dielectric 35 is made uniform, and the discharge flow rate of the processing gas discharged from the discharge holes 24 is made uniform.

  As described above, in the processing gas discharge device 20 in the surface processing apparatus 1 of the present example, the internal electrode 36 includes the core material 37 and the metal foil 38 wound around the outer peripheral surface thereof, and the metal foil 38 is formed by the spring. Since it is configured to have a back characteristic and the surface of the metal foil 38 is in contact with the inner peripheral surface of the internal dielectric 35 by spring back, the internal electrode 36 (metal foil 38) is connected to the internal dielectric 35. The inner peripheral surface can be completely brought into contact without causing a gap.

  As a result, it is possible to prevent discharge from occurring between the internal dielectric 35 and the internal electrode 36 and to prevent wasteful power consumption. The dielectric 35 can be cooled efficiently and uniformly, and the temperature rise of the internal dielectric 35 can be prevented to prevent the internal dielectric 35 from being damaged.

  The thickness of the metal foil 38 is preferably set in the range of 20 μm to 50 μm. In this way, it is possible to facilitate manufacturing and handling and to make it easy to wind in a cylindrical shape. This is because if the thickness is less than 20 μm, it is too thin to cause manufacturing problems and handling problems, and if the thickness is more than 50 μm, the strength is increased and it is difficult to wind the tube.

  Further, since the core material 37 and the cooling pipe 41 are configured in a double pipe structure, and the first connection pipe 44 and the second connection pipe 45 are connected to the other end side of the core material 37 and the cooling pipe 41, the internal dielectric 35 Maintenance can be efficiently performed from one side. In addition, unlike the case where the connecting pipes 44 and 45 are connected to both ends of the core member 37, it is not necessary to provide the space for arranging the connecting pipes on both sides of the internal dielectric 35, and only one side is required. It can also be made compact.

  In addition, since the supply hole 23 is composed of a plurality of slit holes formed in a line so that the longitudinal direction is along the axis of the external dielectric 22, the supply hole is slit compared to the case where the supply hole is composed of one slit hole. The length in the longitudinal direction per hole is shortened, the slit width L2 is easily processed to be constant, and the longitudinal direction of the slit hole (slit portion 23a) is easily processed in parallel with the axis of the external dielectric 22. The processing accuracy of the slit hole can be improved.

  As a result, the process gas supplied from the supply hole 23 between the external dielectric 22 and the internal dielectric 35 is made to be substantially uniform in the axial direction of the external dielectric 22 and discharged from the discharge hole 24. The gas flow rate can be made substantially uniform.

  Moreover, since the discharge hole 24 is composed of a plurality of slit holes formed in a row so that the longitudinal direction thereof is along the axis of the external dielectric 22, as in the case of the supply hole 23, the slit hole can be easily processed. The processing accuracy can be improved, and the flow rate of the processing gas in the axial direction of the external dielectric 22 discharged from the discharge hole 24 to the outside can be made substantially uniform.

  The lengths L1 and L4 in the longitudinal direction of the slit portions 23a and 24a are preferably set in the range of 300 mm to 1200 mm. In this way, the lengths of the slit portions 23a and 24a are preferable. The flow rate of the processing gas supplied from the supply hole 23 between the external dielectric 22 and the internal dielectric 35 or discharged to the outside from the discharge hole 24 can be made substantially uniform. This is because when the lengths L1 and L4 in the longitudinal direction of the slit portions 23a and 24a are shorter than 300 mm, it is not necessary to shorten the length per slit hole and provide a plurality of slit holes. This is because if the lengths L1 and L4 in the longitudinal direction of 24a are longer than 1200 mm, the slit holes cannot be processed with high accuracy.

  In addition, the slit width L2 of the slit portion 23a is preferably set in a range of 0.2 mm to 2.0 mm. In this way, it is possible to facilitate processing, or from the supply hole 23 to the external dielectric 22 and the inside. It is possible to easily adjust the flow rate and flow rate of the processing gas supplied to the dielectric 35. This causes a problem that processing becomes difficult when the slit width L2 is smaller than 0.2 mm, and when the slit width L2 is larger than 2.0 mm, the external dielectric 22 and the internal dielectric 35 are supplied from the supply hole 23. This is because it becomes difficult to adjust the flow rate and flow rate of the processing gas supplied between the two.

  Further, the distances L3 and L6 between the adjacent end portions of the slit holes are preferably set in the range of 0.5 mm to 2.0 mm, and this prevents the strength of the external dielectric 22 from being reduced. Or a portion where the processing gas is not supplied between the outer dielectric 22 and the inner dielectric 35 from the supply hole 23 or a portion where the processing gas is not discharged to the outside from the discharge hole 24 is narrowed, thereby causing unevenness in the flow rate of the processing gas. Can be reduced. This is because if the distances L3 and L6 between the end portions are smaller than 0.5 mm, the strength between the end portions is lowered and the risk of causing cracks and cracks increases. , L6 is larger than 2.0 mm, there are wide portions where the processing gas is not supplied from the supply hole 23 between the external dielectric 22 and the internal dielectric 35 and where the processing gas is not discharged outside from the discharge hole 24. This is because the unevenness of the processing gas flow rate becomes large.

  In addition, round holes 23b and 24b having diameters D1 and D2 larger than the slit widths L2 and L5 are formed at both ends in the longitudinal direction of the slit portions 23a and 24a, respectively, so as to alleviate stress concentration at the slit hole ends. Therefore, even if an impact is applied to the external dielectric 22, it is difficult to cause cracks or cracks at the end portions, and damage can be prevented, and handling can be facilitated. In addition, since the processing gas supplied or discharged from the round holes 23b and 24b does not supply processing gas or discharge processing gas, the processing gas flow in the portion between the slit holes is supplemented. The processing gas flow rate can be made uniform at a short distance from the hole 24.

  The diameters D1 and D2 of the round holes 23b and 24b are preferably set in the range of 2 to 6 times the slit widths L2 and L5. It is possible to prevent the dielectric 22 from being damaged, or to reduce the difference in flow rate of the processing gas between the slit portions 23a, 24a and the round holes 23b, 24b. This is because when the diameters D1 and D2 are smaller than twice the slit widths L2 and L5, the stress concentration is insufficiently relaxed and the external dielectric 22 is easily damaged, and the diameters D1 and D2 are the slit widths L2 and L5. Is larger than 6 times, the flow rate difference between the processing gas supplied or discharged from the slit portions 23a and 24a and the processing gas supplied or discharged from the round holes 23b and 24b becomes too large. Because.

  In addition, a trumpet-shaped conductive member 29 including an attachment portion 30 and an inclined portion 31 is provided at both ends of the holding member 27 in the axial direction of the external dielectric 22, and the external dielectric 22 is connected to the outer peripheral surface by the conductive member 29. Since the electric force lines are directed toward the inclined portion 31 side of the conductive member 29 so that the electric lines of force are applied to both ends of the holding member 27 (the surface of the mounting portion 30). Concentration can be mitigated, and it is possible to prevent electric field lines from concentrating at both ends of the holding member 27 (external electrode 26) and increasing the electric field in the vicinity of both ends.

  Thereby, it is possible to suppress the concentration of the discharge at the both end portions, to prevent local temperature rise of the external dielectric 22 and the internal dielectric 35 near the both ends due to the concentration of the discharge, and to the external dielectric 22. It is possible to prevent the internal dielectric 35 from being damaged.

  Note that the inclination angle θ of the inclined portion 31 with respect to the axis of the external dielectric 22 is preferably set in the range of 2 ° to 30 °. In this way, the concentration of electric lines of force can be effectively reduced. Concentration of discharge can be suppressed, and local temperature rise of the outer dielectric 22 and the inner dielectric 35 can be more effectively prevented. This is because, when the tilt angle θ is smaller than 2 °, the lines of electric force concentrate on the upper end of the tilted portion 31 in the tilt direction, and the electric discharge concentrates on the end, and the tilt angle θ is larger than 30 °. Since the lines of electric force concentrate on the lower end of the inclined portion 31 in the inclination direction (the root portion of the inclined portion 31) and the discharge concentrates on the end, the outer dielectric 22 and the inner dielectric 35 This is because a local temperature rise cannot be prevented.

  Therefore, according to the surface treatment apparatus 1 of this example, the process gas discharge apparatus 20 prevents discharge from occurring between the internal dielectric 35 and the internal electrode 36, thereby preventing wasteful power consumption. In addition, the internal dielectric 35 can be efficiently and uniformly cooled to prevent the internal dielectric 35 from being damaged, and is supplied between the external dielectric 22 and the internal dielectric 35 from the supply hole 23. The flow rate of the processing gas to be discharged and the flow rate of the processing gas discharged from the discharge hole 24 to the outside can be made uniform, and the strength of the external dielectric 22 can be increased. Since the local temperature rise of the body 35 can be prevented to prevent them from being damaged, the plasma surface treatment can be performed uniformly and efficiently, the cost for the plasma surface treatment can be reduced, Simplification It is possible to achieve.

  As mentioned above, although one Embodiment of this invention was described, the specific aspect which this invention can take is not limited to this at all.

  In the above example, the cooling pipe 41 is provided inside the core material 37 to form a double pipe structure. However, the cooling pipe 41 is omitted, both ends of the core material 37 are opened, and the first connection pipe 44 is provided. May be connected to one end of the core material 37, and the second connection pipe 45 may be connected to the other end of the core material 37. In this case, the internal dielectric 35 is cooled by the coolant flowing through the core material 37 from the one end side to the other end side of the core material 37.

  Further, the internal electrode 36 can be configured only from the metal foil 38 without the core material 37. In this case, the high frequency power supply 39 is configured to apply a high frequency voltage between the metal foil 38 and the external electrode 26.

  Further, the metal foil 38 is omitted, and metal powder is filled between the outer peripheral surface of the core material 37 and the inner peripheral surface of the inner dielectric 35, and the core material 37 and the inner dielectric 35 are filled by filling the metal powder. You may make it fill the gap between them. In this case, it is preferable to employ a metal powder having excellent conductivity, thermal conductivity and corrosion resistance, such as silver. The particle size of the metal powder is preferably about 0.2 μm to 1.0 μm.

  In the above example, the substrate K is configured to be processed. However, the processing target is not limited to the substrate K, and the processing gas is not limited to the main component of nitrogen gas. Absent.

It is the front sectional view showing the schematic structure of the surface treatment apparatus concerning one embodiment of the present invention. It is sectional drawing of the arrow AA direction in FIG. It is sectional drawing of the arrow BB direction in FIG. It is the top view which showed schematic structure of the external dielectric material concerning this embodiment. FIG. 5 is a bottom view of the external dielectric shown in FIG. 4. It is explanatory drawing which showed schematic structure of the internal electrode which concerns on this embodiment. It is sectional drawing which showed schematic structure, such as an internal electrode and a cooling pipe which concerns on this embodiment. It is the bottom view which showed schematic structure of the connection member which concerns on this embodiment, and a baffle plate.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Surface treatment apparatus 10 Conveyance roller 20 Processing gas discharge apparatus 21 Discharge mechanism 22 External dielectric 23 Supply hole 24 Discharge hole 26 External electrode 27 Holding member 29 Conductive member 30 Mounting part 31 Inclination part 35 Internal dielectric 36 Internal electrode 37 Core material 38 Metal foil 39 High frequency power supply 40 Coolant circulation mechanism 41 Cooling pipe 42 Metal wire 50 Gas supply mechanism 51 Introducing pipe 52 Process gas generator 53 Connecting member 54 Rectifying plate

Claims (5)

A processing gas discharge device comprising discharge means for converting a processing gas into plasma and discharging, and gas supply means for supplying the processing gas to the discharge means;
The discharge means is
An external dielectric made of a tubular member and having a supply hole to which the processing gas is supplied and a discharge hole for discharging the supplied processing gas opened on an outer peripheral surface;
An outer electrode provided on the outer peripheral surface of the external dielectric at a position that does not block the supply hole and the discharge hole, and is grounded;
An inner dielectric formed of a tubular member and provided in the outer dielectric tube so as to be spaced apart from the inner peripheral surface of the outer dielectric and coaxially with the outer dielectric;
An internal electrode provided in the internal dielectric tube;
Voltage application means for applying a voltage between the internal electrode and the external electrode,
The gas supply means is configured to supply the processing gas between the external dielectric and the internal dielectric from the supply hole,
The processing gas supplied between the external dielectric and the internal dielectric is turned into plasma by applying a voltage between the internal electrode and the external electrode by the voltage applying means, and then the discharge hole. In the processing gas discharge device configured to be discharged from the outside,
The internal electrode is composed of a sheet-like metal foil wound in a cylindrical shape so that a central axis is parallel to the axis of the internal dielectric, and the metal foil is deformed by applying an external force, and the external force The shape of the metal foil is restored to the original shape by removing the surface of the metal foil, and the shape of the metal foil is configured to abut against the inner peripheral surface of the internal dielectric by a shape restoration action. Processing gas discharge device. The discharge means further comprises a cooling fluid circulation means for circulating a cooling fluid inside the internal electrode,
The internal electrode is composed of the metal foil and a tubular core material that is disposed in a tube of the internal dielectric, and the metal foil is wound around an outer peripheral surface,
The cooling fluid circulation means has a first connecting pipe and a second connecting pipe connected to both ends of the core material, and supplies the cooling fluid from the first connecting pipe and the supplied cooling fluid to the second connecting pipe. Configured to reflux from the connecting pipe,
The processing gas discharge apparatus according to claim 1, wherein the voltage applying unit is configured to apply a voltage between the core material and the external electrode. The discharge means further comprises a cooling fluid circulation means for circulating a cooling fluid inside the internal electrode,
The internal electrode is composed of the metal foil and a tubular core material that is disposed in the internal dielectric tube in a state where one end is sealed, and the metal foil is wound around an outer peripheral surface,
The cooling fluid circulating means includes a cooling pipe having one end and an outer peripheral surface spaced from the inner surface of the core material, a first connection pipe connected to the other end side of the cooling pipe, and the other end side of the core material. A second connecting pipe connected between the core material and the cooling pipe, configured to supply a cooling fluid from one of the connecting pipes and to recirculate the supplied cooling fluid from the other of the connecting pipes. ,
The processing gas discharge apparatus according to claim 1, wherein the voltage applying unit is configured to apply a voltage between the core material and the external electrode.   The processing gas discharge apparatus according to claim 1, wherein the metal foil has a thickness of 20 μm to 50 μm. Support means for supporting the object to be treated;
A processing gas discharge device according to any one of claims 1 to 4,
The processing gas discharge device is disposed so that the discharge hole faces the processing object supported by the support means,
A surface treatment apparatus configured to treat the surface of the object to be treated with a treatment gas discharged from the treatment gas discharge apparatus.

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