阅读说明：本技术 活性气体生成装置 (Active gas generating device ) 是由 渡边谦资 有田廉 于 2019-02-13 设计创作，主要内容包括：本发明的目的在于提供能够实现装置构成的简化及小型化且能够抑制活性气体失活的现象的活性气体生成装置的构造。在本发明中,电极单元基座(2)中设置的气体流通槽(24)、高压电极用槽(21)及接地电极用槽(22)俯视时呈螺旋状。以使高压导通孔(41)与高压导通点(P1)俯视时一致的方式在电极单元基座(2)的表面上配置电极单元盖(1)。以俯视时高压开口部(61)涵盖高压导通孔(41)的全部的方式在电极单元盖(1)的表面上配置电极冷却板(3)。而且,以俯视时接地导通槽(62)、接地导通孔(42)及接地导通点(P2)一致的方式在电极单元基座(2)的表面上配置电极单元盖(1)及电极冷却板(3)。(The purpose of the present invention is to provide a structure of an active gas generation device that can simplify and reduce the size of the device structure and can suppress the phenomenon of active gas deactivation. In the present invention, a gas flow groove (24), a high-voltage electrode groove (21), and a ground electrode groove (22) provided in an electrode unit base (2) are formed in a spiral shape when viewed from above. An electrode cell cover (1) is disposed on the surface of an electrode cell base (2) so that a high-voltage via hole (41) and a high-voltage via point (P1) coincide with each other in a plan view. An electrode cooling plate (3) is disposed on the surface of the electrode unit cover (1) so that the high-voltage opening (61) covers the entire high-voltage via hole (41) in a plan view. The electrode unit cover (1) and the electrode cooling plate (3) are disposed on the surface of the electrode unit base (2) so that the ground conduction groove (62), the ground conduction hole (42), and the ground conduction point (P2) coincide with each other in a plan view.)

1. An active gas generation device (10) that generates an active gas by activating a source gas supplied to a discharge space where dielectric barrier discharge occurs, the active gas generation device comprising:

an electrode unit base (2) having a 1 st electrode (11) and a 2 nd electrode (12) and receiving an alternating voltage from the outside;

an electrode unit cover (1) disposed on a surface of the electrode unit base;

an electrode pressing plate (3) which is provided on the surface of the electrode unit cover and presses the electrode unit cover with a pressing force applied from above; and

a device case (30) for accommodating the electrode unit base, the electrode unit cover, and the electrode pressing plate,

the electrode unit base has:

1 st and 2 nd electrode grooves (21, 22) provided at a predetermined depth from the surface of the electrode unit base;

the 1 st and 2 nd electrodes embedded in the 1 st and 2 nd electrode grooves, respectively, and having conductivity; and

a gas internal flow path (24) formed in the electrode unit base and through which a source gas flows,

the gas internal flow path is provided in a spiral shape in a plan view, the 1 st and 2 nd electrodes are provided in a spiral shape in a plan view together with the gas internal flow path,

the 1 st and 2 nd electrodes have 1 st and 2 nd conduction points (P11, P12) at ends thereof,

the 1 st and 2 nd electrodes are disposed on both sides of the gas internal flow path so as to face each other with the gas internal flow path and a part of the electrode unit base interposed therebetween, a region in the gas internal flow path between the 1 st and 2 nd electrodes serves as the discharge space, and dielectric barrier discharge is generated in the discharge space by receiving the alternating voltage,

the electrode unit base further comprises at least one gas ejection port (6) provided below the discharge space so as to communicate with the gas internal flow path,

an active gas obtained by activating the raw material gas supplied into the discharge space is ejected from the at least one gas ejection port,

the electrode unit cover has:

a gas relay hole (46) provided so as to be connected to the gas internal flow path of the electrode unit base; and

1 st and 2 nd through holes (41, 42) provided in regions coinciding with the 1 st and 2 nd conduction points in a plan view and formed so as to penetrate therethrough,

the electrode pressing plate includes:

an opening (61) that covers the 1 st through hole in a plan view and has a shape wider than the 1 st through hole; and

a gas supply hole (66) provided in a region that coincides with the gas relay hole in a plan view,

the electrode pressing plate is electrically connected to the 2 nd conduction point through the 2 nd through hole.

2. The active gas generating apparatus according to claim 1,

the 2 nd electrode is set to a ground level, the 1 st electrode is applied with the alternating voltage,

the 1 st and 2 nd electrodes are arranged such that the 2 nd electrode is located at the outermost periphery of the electrode unit base in a plan view.

3. The active gas generating apparatus according to claim 2,

the active gas generator further includes:

a cooling medium circulating mechanism (8, 37) for supporting the electrode unit base from the back side and circulating the cooling medium in the electrode pressing plate,

the electrode pressing plate has a cooling function of cooling the electrode unit base from the electrode unit cover side.

4. The active gas generating apparatus according to claim 3,

the electrode unit base, the electrode unit cover, the electrode pressing plate, and the cooling medium circulation mechanism are integrally connected.

5. Active gas generating apparatus according to any one of claims 2 to 4,

the active gas generator further includes:

an AC voltage supply terminal (71) mounted on an upper portion of the device case and supplying the AC voltage,

the ac voltage supply terminal is electrically connected to the 1 st conduction point via the opening and the 1 st through hole.

Technical Field

The present invention relates to an active gas generator using dielectric barrier discharge, which has a parallel plate electrode structure and is used in a semiconductor film forming apparatus.

Background

One of the installation positions of an active gas generator having a parallel plate electrode structure and utilizing dielectric barrier discharge is disposed above a processing object such as a wafer. In this method, since it is necessary to uniformly blow the active gas to the entire object to be processed, a shower plate for uniformly blowing the gas is generally disposed between the active gas generating device and the object to be processed.

However, since the active gas flow region in the shower plate is a non-discharge space that does not participate in the dielectric barrier discharge, the period of time in which the active gas flows from the active gas flow region in the shower plate is a period of time in which the active gas is deactivated. Therefore, when the active gas generating device generates an active gas having an extremely short lifetime such as nitrogen radicals, deactivation of the radicals is significantly promoted in the process of flowing through the shower plate.

Thus, the use of the shower plate in the active gas generator is not preferable because the phenomenon of deactivation of the active gas is more likely to occur.

As a conventional active gas generating apparatus not using a shower plate, for example, an atmospheric pressure plasma reaction apparatus disclosed in patent document 1 is known.

In the 1 st conventional technique disclosed in patent document 1, a flat plate-like electrode arranged to face each other is arranged in a vertical shape, and an active gas generated by discharge between the electrodes is blown onto a substrate. In the conventional technique 1, a plurality of electrode structures are arranged for processing a large-area substrate.

As described above, according to the related art 1, the number of electrode structures is increased, and a plurality of electrode structures are used, whereby it is possible to easily cope with the area of the substrate.

As another active gas generating apparatus not using a shower plate, for example, there is a plasma processing apparatus disclosed in patent document 2.

In the 2 nd prior art disclosed in patent document 2, a plurality of gas ejection holes are provided in one of flat plate-shaped electrodes arranged to face each other in the horizontal direction, so that a shower plate is not required and a large-sized substrate can be processed.

Paragraph [0022] of patent document 2, and fig. 1 and 2 disclose the 1 st basic configuration. The specific configuration is as follows. Note that numerals in parentheses are reference numerals used in patent document 2.

The 1 st basic constitution adopts the following configuration: a conductive layer (12) is formed on the surface of a high-voltage electrode (8) having no conductivity, and a grounded metal plate (2) is brought into contact with a ground electrode (7) having no conductivity and located below the high-voltage electrode (8).

Further, paragraph [0063] and fig. 9 of patent document 2 disclose the 2 nd basic configuration. The specific configuration is as follows. Note that numerals in parentheses are reference numerals used in patent document 2.

In the 2 nd basic configuration, a configuration is adopted in which the ground conductive layer (41) is embedded inside the ground electrode (7) in addition to the 1 st basic configuration.

Disclosure of Invention

Problems to be solved by the invention

In the 1 st prior art disclosed in patent document 1, a device capable of dealing with a large-area object to be processed can be realized by adopting a plurality of electrode structures.

However, in the case of the conventional technique 1, if a plurality of electrode structures are adopted, it is necessary to provide a high voltage electrode and a ground electrode in each of the plurality of electrode structures, and the device structure becomes complicated. Further, in the conventional technique 1, since the flow direction of the raw material gas is vertical, in order to increase the concentration of the active gas, it is necessary to sufficiently increase the vertical formation length of the high-voltage electrode and the ground electrode constituting the electrode structure, and the height of the apparatus inevitably increases, resulting in an increase in the size of the apparatus.

As described above, the prior art 1 disclosed in patent document 1 has a problem of complicating and enlarging the device structure.

Next, the 2 nd prior art disclosed in patent document 2 is discussed. In addition, numerals in parentheses are reference numerals used in patent document 2.

In the above-described basic configuration 1, since the electric field intensity at the surface such as the end of the conductive layer 12 becomes very high, dielectric breakdown occurs in the gas layer of the discharge portion 3, and abnormal discharge occurs in the metal conductive layer 12, and particles and metal vapor are generated in the discharge portion 3. That is, substances evaporated from the conductive layer (12), the chamber (1), or the partition plate (2) become a source of contamination in accordance with abnormal discharge of the conductive layer (12).

Since the surface layer of the conductive layer (12) is connected to the discharge space (gap (9)) between the electrodes, there is a possibility that the evaporated molecules of the conductive layer (12) are mixed into the active gas and contaminate the substrate (15) during the gas transport to the discharge space.

As described above, the following problems occur in the 1 st basic configuration of the 2 nd conventional art: particles and metal vapor are generated in the discharge section (3), and the substrate (15) may be contaminated.

In order to reliably prevent the substrate (15) from being contaminated, it is necessary to sufficiently increase the insulation distance of the discharge section (3). However, increasing the insulation distance is not preferable because it inevitably increases the size of the device configuration.

On the other hand, in the 2 nd basic structure of patent document 2, the conductive layer (12) of the high-voltage electrode (8) is exposed on the electrode surface in the same manner as in the 1 st basic structure. In theory, the conductive layers on both the high-voltage side and the ground side can be prevented from being exposed by performing the same treatment as that for the ground electrode also for the high-voltage electrode.

Fig. 15 is a sectional view showing a sectional configuration of the 2 nd basic constitution in the 2 nd prior art. The void 109 shown in the figure corresponds to the void (9), the 1 st electrode 107 corresponds to one ground electrode (7), the fine hole 110 corresponds to the fine hole (10), the ground conductive layer 141 corresponds to the ground conductive layer (41), and the ground gap 142 corresponds to the ground gap (42).

As shown in the drawing, the opening H141 of the ground conductive layer 141 covers the fine pores 110 and is formed in a shape wider than the fine pores 110, so that a ground gap 142 is generated between the electrode unit 100 and the ground conductive layer 141. The ground gap 142 is not formed with the ground conductive layer 141.

Therefore, in the gap 109 serving as a discharge space between the electrodes, a region above the ground gap 142 serves as a non-discharge space, and when gas flows through the non-discharge space, the active gas is deactivated, and the concentration of the active gas is lowered.

Next, a modification in which the ground conductive layer 141 is modified so as to have no ground gap 142 (the pore 110 is set to have the same size as the opening region of the opening region H141 of the main body pole portion) is considered.

Fig. 16 is a sectional view showing a sectional structure of a modification of the 2 nd basic configuration in the 2 nd prior art. The region shown in fig. 16 corresponds to an enlarged region of the region of interest R7 and the vicinity thereof in fig. 15.

In the modification of the 2 nd basic configuration, when the fine pores 110 are viewed in the cross-sectional direction, the ground conductive layer 141 is exposed to the fine pores 110. Therefore, when the fine pores 110 near the exposed portion of the ground conductive layer 141 are damaged, the conductive layer component of the ground conductive layer 141 becomes a contaminant and is released to the outside.

As described above, the problem of the decrease in the concentration of the active gas is caused in the 2 nd basic configuration (fig. 15) of the 2 nd prior art, and the problem of the generation of contaminants is caused in the modification (fig. 16) of the 2 nd basic configuration.

The present invention has been made to solve the above problems, and an object of the present invention is to provide an active gas generator capable of simplifying and reducing the size of the device configuration, and capable of suppressing the deactivation of the active gas.

Means for solving the problems

An active gas generator according to the present invention generates an active gas by activating a source gas supplied to a discharge space where dielectric barrier discharge is generated, and includes: an electrode unit base having a 1 st electrode and a 2 nd electrode and receiving an alternating voltage from the outside; an electrode unit cover disposed on a surface of the electrode unit base; an electrode pressing plate provided on a surface of the electrode unit cover and pressing the electrode unit cover with a pressing force applied from above; and a device case that accommodates the electrode unit base, the electrode unit cover, and the electrode pressing plate, wherein the electrode unit base includes: 1 st and 2 nd electrode grooves formed at a predetermined depth from the surface of the electrode unit base; the 1 st and 2 nd electrodes embedded in the 1 st and 2 nd electrode grooves, respectively, and having conductivity; and a gas internal flow path formed in the electrode unit base and through which a source gas flows, the gas internal flow path being provided in a spiral shape in plan view, the 1 st and 2 nd electrodes being provided in a spiral shape in plan view together with the gas internal flow path, the 1 st and 2 nd electrodes having 1 st and 2 nd conduction points at end portions thereof, the 1 st and 2 nd electrodes being disposed on both sides of the gas internal flow path so as to face each other with a part of the electrode unit base and the gas internal flow path interposed therebetween, a region in the gas internal flow path between the 1 st and 2 nd electrodes serving as the discharge space and generating a dielectric barrier discharge in the discharge space by receiving the alternating voltage, the electrode unit base further including at least one gas ejection hole provided in communication with the gas internal flow path below the discharge space, and an electrode unit cover configured to eject an active gas obtained by activating the raw material gas supplied into the discharge space from the at least one gas ejection port, the electrode unit cover including: a gas relay hole provided so as to be connected to the gas internal flow path of the electrode unit base; and 1 st and 2 nd through holes provided in regions coinciding with the 1 st and 2 nd conduction points in a plan view and formed to penetrate therethrough, respectively, the electrode pressing plate including: an opening portion that covers the 1 st through hole in a plan view and has a shape wider than the 1 st through hole; and a gas supply hole provided in a region that coincides with the gas relay hole in a plan view, wherein the electrode pressing plate is electrically connected to the 2 nd conduction point via the 2 nd through hole.

Effects of the invention

An active gas generator according to claim 1 of the present invention is an active gas generator comprising an electrode unit base having a gas internal passage formed spirally in a plan view and at least one gas ejection port provided below a discharge space so as to communicate with the gas internal passage.

Therefore, the active gas generator according to the present invention recited in claim 1 has an effect of effectively suppressing the phenomenon of the active gas being deactivated because no non-discharge space participating in the dielectric barrier discharge is formed between at least one gas ejection port and the discharge space.

Further, since the electrode unit base can exhibit the above-described effects with a relatively simple configuration in which at least one gas ejection port, the 1 st electrode, the 2 nd electrode, and the gas internal flow path are provided, the device configuration of the active gas generator can be simplified.

In the active gas generator according to the present invention described in claim 1, the gas internal flow path is provided in a spiral shape in plan view. Therefore, the active gas can be ejected from the at least one gas ejection port in a state of being saturated in gas concentration without increasing the area of the electrode unit base itself, and the device can be miniaturized accordingly.

In the active gas generator according to claim 1 of the present invention, the electrode cell cover has a 1 st via hole and a 2 nd via hole which are provided in a region coinciding with the 1 st via point and the 2 nd via point in a plan view and which penetrate therethrough, respectively.

Therefore, the electrode cell cover can seal the upper side of the electrode cell base while ensuring the electrical connection function between the 1 st and 2 nd conduction parts and the outside through the 1 st and 2 nd conduction holes.

Further, since the electrode pressing plate has the opening portion covering the 1 st through hole in a plan view and having a shape wider than the 1 st through hole, the function of electrically connecting the 1 st through hole and the outside can be secured through the 1 st through hole. The electrode pressing plate can electrically connect the 2 nd via hole to the electrode pressing plate itself via the 2 nd via hole.

Further, the electrode pressing plate can stably press the electrode unit cover.

The objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description and the accompanying drawings.

Drawings

Fig. 1 is an explanatory view showing a cross-sectional structure of an active gas generator according to an embodiment of the present invention.

Fig. 2 is a perspective view illustrating the configuration of the electrode unit base shown in fig. 1.

Fig. 3 is a perspective view showing only the high-voltage electrode groove shown in fig. 2.

Fig. 4 is a perspective view showing only the ground electrode groove shown in fig. 2.

Fig. 5 is an explanatory view schematically showing the configuration of an electrode unit used in the active gas generator according to the embodiment.

Fig. 6 is a plan view showing a planar configuration of the electrode unit base as viewed from above.

Fig. 7 is a sectional view showing a sectional configuration of the electrode unit base.

Fig. 8 is a plan view showing a planar configuration of the electrode unit base as viewed from below.

Fig. 9 is a perspective view showing the configuration of the electrode unit cover.

Fig. 10 is a perspective view showing the configuration of the electrode cooling plate.

Fig. 11 is a perspective view showing the configuration of the generator base flange.

Fig. 12 is a perspective view showing the configuration of the cooling water manifold.

Fig. 13 is an explanatory diagram showing an enlarged flow of cooling water in the electrode cooling plate.

Fig. 14 is an explanatory diagram schematically showing a combined configuration of the electrode cooling plate, the electrode unit cover, the electrode unit base, the cooling water manifold, and the generator base flange.

Fig. 15 is a sectional view showing a sectional configuration of the 2 nd basic constitution in the 2 nd prior art.

Fig. 16 is a sectional view showing a sectional structure of a modification of the 2 nd basic configuration in the 2 nd prior art.

Detailed Description

< embodiment >

(integral constitution)

Fig. 1 is an explanatory diagram showing a cross-sectional structure of an active gas generator 10 according to an embodiment of the present invention. The active gas generator 10 of the present embodiment generates an active gas by activating a raw material gas supplied to a discharge space where dielectric barrier discharge is generated.

The active gas generator 10 includes a device case 30, an electrode unit cover 1, an electrode unit base 2, an electrode cooling plate 3, a generator base flange 8, a cooling water manifold 37, and a high-voltage terminal 71 as main components.

The electrode unit base 2 has a high voltage electrode 11 as a 1 st electrode and a ground electrode 12 as a 2 nd electrode, and receives an ac voltage from the outside via a high voltage terminal 71.

The electrode unit cover 1 is disposed on the surface of the electrode unit base 2. The electrode unit cover 1 and the electrode unit base 2 are each made of a dielectric material.

An electrode cooling plate 3 as an electrode pressing plate is provided on the surface of the electrode unit base 2 and has conductivity. The electrode cooling plate 3 can press the electrode unit cover 1 by a pressing force applied by an elastic member such as a spring, not shown, provided above the electrode cooling plate 3.

The device case 30 accommodates the electrode unit base 2, the electrode unit cover 1, and the electrode cooling plate 3 in the accommodation space SP 30.

The generator base flange 8 has an opening H8 in the central region so as to expose all of the plurality of gas ejection ports 6 provided on the back surface of the electrode unit base 2.

Further, on the rear surface of the electrode unit base 2, a region located outside the opening H8 is disposed on the surface of the generator base flange 8. Therefore, the generator base flange 8 supports the electrode unit base 2 from the back side.

The cooling water manifold 37 is disposed adjacent to the electrode unit cover 1 and the electrode unit base 2 on a part of the surface of the generator base flange 8. The surface height of the cooling water manifold 37 is matched to the surface height of the electrode unit cover 1, and the electrode cooling plate 3 is disposed not only on the electrode unit cover 1 but also on the surface of the cooling water manifold 37.

By the combined structure of the generator base flange 8 and the cooling water manifold 37, a cooling medium circulating mechanism for circulating cooling water as a cooling medium in the electrode cooling plate 3 is constituted as described later in detail. Therefore, the electrode cooling plate 3 has a cooling function of cooling the electrode unit base 2 from the electrode unit cover 1 side.

On the side (right side in fig. 1) across the opening H8, the electrode cooling plate 3, the cooling water manifold 37, and the generator base flange 8 are coupled by mounting screws 48. On the other side (left side in fig. 1) across the opening H8, the electrode cooling plate 3 and the generator base flange 8 are directly coupled by mounting screws 48.

In this way, the electrode cooling plate 3, the electrode unit cover 1, the electrode unit base, and the cooling medium circulation mechanism (the cooling water manifold 37+ the generator base flange 8) are integrally connected by the mounting screws 48. The device case 30 is directly coupled to the generator base flange 8 by mounting screws 48. Thus, the device housing 30 is fixed to the generator base flange 8.

A high-voltage terminal 71 serving as an ac voltage supply terminal for supplying ac voltage is attached to the upper portion of the device case 30 by an attachment screw 47, and the high-voltage terminal 71 is electrically connected to the high-voltage electrode 11 in the electrode unit base 2 as described later.

A gas supply flange 39 is provided on one side surface of the apparatus casing 30, and the raw material gas is supplied from the gas supply flange 39 into the housing space SP30 through the raw material gas supply passage 33.

(electrode unit base 2)

Fig. 2 is a perspective view showing the configuration of the electrode unit base 2 shown in fig. 1. Fig. 3 is a perspective view particularly showing only the high-voltage electrode groove 21 (1 st electrode groove) shown in fig. 2. Fig. 4 is a perspective view particularly showing only the ground electrode groove 22 (2 nd electrode groove) shown in fig. 2. Fig. 2 to 4 show XYZ rectangular coordinate systems.

Fig. 5 is an explanatory view schematically showing the structure of the electrode unit 100 used in the active gas generator 10 according to embodiment 1. Fig. 5 shows a ZYZ orthogonal coordinate system. Fig. 6 to 8 shown below also show a ZYZ orthogonal coordinate system in the same manner as fig. 5.

As shown in fig. 5, the electrode unit 100 includes, as main components, an electrode unit cover 1 and an electrode unit base 2 each made of a dielectric material. The electrode unit cover 1 is disposed on the surface of the electrode unit base 2.

Fig. 6 is a plan view showing a planar configuration of the electrode unit base 2 as viewed from above. As shown in fig. 2 and 6, the electrode unit base 2 is circular in plan view.

As shown in fig. 2 to 4 and 6, the electrode unit base 2 is provided with a gas flow groove 24, a high-voltage electrode groove 21 and a ground electrode groove 22, which are hollowed out from the surface of the electrode unit base 2. The gas flow groove 24, the high-voltage electrode groove 21, and the ground electrode groove 22 are formed in a spiral shape in plan view.

Fig. 7 is a sectional view showing a sectional configuration of the electrode unit base 2. The section a-a of fig. 6 becomes fig. 7.

As shown in fig. 7, the gas flow groove 24, the high-voltage electrode groove 21, and the ground electrode groove 22 are bored such that the bottom surfaces thereof are slightly higher than the bottom surface of the electrode unit base 2. The gas flow groove 24, the high-voltage electrode groove 21, and the ground electrode groove 22 are formed to the same depth D2 from the surface.

In this way, the electrode unit base 2 has the 1 st and 2 nd electrode grooves, i.e., the high-voltage electrode groove 21 and the ground electrode groove 22, which are formed at the same depth from the surface.

The electrode unit base 2 has a gas flow groove 24 formed in a groove shape at a depth D2 (predetermined formation depth) from the surface and serving as an internal gas flow passage.

The high-voltage electrode groove 21 and the ground electrode groove 22 are disposed on both side surfaces of the gas flow groove 24 in the electrode unit base 2 so as to face each other with a part of the electrode unit base 2 and the gas flow groove 24 interposed therebetween, and are provided in a spiral shape in plan view together with the gas flow groove 24.

The high-voltage electrode 11 as the 1 st electrode is embedded in the high-voltage electrode groove 21 as the 1 st electrode groove, and the ground electrode 12 as the 2 nd electrode is embedded in the ground electrode groove 22 as the 2 nd electrode groove. At this time, the high-voltage electrode 11 is embedded in the entire high-voltage electrode groove 21 so as not to generate a gap in the high-voltage electrode groove 21, and the ground electrode 12 is embedded in the entire ground electrode groove 22 so as not to generate a gap in the ground electrode groove 22.

As shown in fig. 2 and 6, in the active gas generator 10 of the present embodiment, the high-voltage electrode 11 and the ground electrode 12 are disposed in the electrode unit 100 such that the ground electrode 12 is located at the outermost periphery of the electrode unit base 2 in a plan view.

Therefore, the high-voltage electrode 11 and the ground electrode 12 are disposed on both side surfaces of the gas flow groove 24 in the electrode unit base 2 so as to face each other through a part of the electrode unit base 2 and the gas flow groove 24, and are provided in a spiral shape in plan view together with the gas flow groove 24. The region in the gas flow groove 24 between the high-voltage electrode 11 and the ground electrode 12 serves as a discharge space.

Fig. 8 is a plan view showing a planar configuration of the electrode unit base 2 as viewed from below.

As shown in fig. 2 and 6 to 8, a plurality of gas ejection ports 6 are selectively provided in a discrete manner, and the gas ejection ports 6 penetrate through the gas internal flow path, that is, the region of the electrode unit base 2 under the bottom surface of the gas flow groove 24. The plurality of gas ejection holes 6 are provided below the discharge space so as to be continuous with the bottom surface of the gas circulation groove 24. That is, the plurality of gas ejection ports 6 communicate with the gas circulation grooves 24. Therefore, the active gas generated in the gas flow groove 24 can be ejected to the outside from the plurality of gas ejection ports 6.

The electrode unit cover 1 and the electrode unit base 2 are each made of a dielectric material such as alumina.

As shown in fig. 2, 3, 6 and 7, a high voltage conduction point P1 of the high voltage electrode 11 is provided at the center of the surface of the electrode unit base 2. The depth of formation of the high-voltage electrode groove 21 in the high-voltage conduction point vicinity region R21 of the high-voltage conduction point P1, which is the 1 st conduction point, is set to be shallower than the depth D2.

As shown in fig. 2, 4, and 6, a ground conduction point P2 is provided at the tip end portion of the ground electrode 12, which is bent, in the vicinity of the peripheral portion of the surface of the electrode unit base 2. The depth of formation of the ground electrode groove 22 in the ground conduction point vicinity region R22 of the ground conduction point P2 as the 2 nd conduction point is set to be shallower than the depth D2.

The reason why the depth of formation of the high-voltage electrode groove 21 and the ground electrode groove 22 in the high-voltage conduction point vicinity region R21 and the ground conduction point vicinity region R22 is set to be shallower than the depth D2 is that the discharge space is not formed in the high-voltage conduction point vicinity region R21 and the ground conduction point vicinity region R22.

As shown in fig. 2 and 6, the ground conduction point P2 is provided at a position separated from the end of the high-voltage electrode slot 21 by an insulation distance L2. Therefore, the insulating relationship can be reliably maintained between the ground conduction point P2 as the 2 nd conduction point and the high-voltage electrode 11.

(electrode unit cover 1)

Fig. 9 is a perspective view showing the configuration of the electrode unit cover 1. As shown in the drawing, the electrode unit cover 1 is circular in plan view so as to conform to the surface shape of the electrode unit base 2, and includes a high-voltage via hole 41, a ground via hole 42, and a gas relay hole 46.

The high-voltage via hole 41 as a 1 st through hole is provided to penetrate through the center region of the electrode unit cover 1, and the ground via hole 42 and the gas relay hole 46 as a 2 nd through hole are provided to penetrate through the vicinity of the periphery of the electrode unit cover 1.

The high-voltage via hole 41 is a hole for electrical connection to the high-voltage via point P1, the ground via hole 42 is a hole for electrical connection to the ground via point P2, and the gas relay hole 46 is a hole for supplying the raw material gas to the gas flow groove 24 of the electrode unit base 2.

The gas circulation groove 24 is set to be located below the gas relay hole 46 when the electrode unit cover 1 is disposed on the surface of the electrode unit base 2.

Further, since it is not necessary to provide a gas seal such as an O-ring between the electrode unit base 2 and the electrode unit cover 1 for the high-pressure via hole 41, the ground via hole 42, and the gas relay hole 46, the electrode unit 100 (the electrode unit cover 1+ the electrode unit base 2) can be downsized.

(electrode cooling plate 3)

Fig. 10 is a perspective view showing the configuration of the electrode cooling plate 3. As shown in the drawing, the electrode cooling plate 3 has a substantially circular shape having a convex portion in part when viewed in plan so as to conform to the surface shapes of the electrode unit base 2 and the cooling water manifold 37. The electrode cooling plate 3 is disposed on the electrode unit base 2 in a circular region portion except for the convex region.

The electrode cooling plate 3 has a high-voltage opening 61, a ground conduction groove 62, a cooling water supply groove 63, a cooling water inlet hole 64, a cooling water outlet hole 65, and a gas supply hole 66.

The high-voltage opening 61 (opening) is provided through the center region of the electrode unit base 2. When the electrode cooling plate 3 is disposed on the electrode unit cover 1, the high-voltage opening 61 covers the entire high-voltage via hole 41 of the electrode unit cover 1 in a plan view, and has a shape wider than the high-voltage via hole 41.

The ground conduction groove 62 is a groove provided so as not to penetrate from the back surface side of the electrode cooling plate 3, and is provided for electrically connecting to the ground conduction point P2 via the ground conduction hole 42.

The cooling water supply groove 63 is a hollow region provided inside the electrode cooling plate 3 so as not to be exposed on the front and rear surfaces. The cooling water obtained from the cooling water inlet hole 64 flows through the cooling water supply tank 63 along the cooling water flow path 68. The cooling water flowing through the cooling water supply tank 63 is finally discharged from the cooling water outlet 65.

The cooling water inlet hole 64 and the cooling water outlet hole 65 are provided in the convex region of the electrode cooling plate 3. The electrode cooling plate 3 is disposed so that the projection region is located on the surface of the cooling water manifold 37.

The electrode cooling plate 3 can be formed by bonding two plates, each having a cooling water supply groove formed on one side, so that the surfaces on which the cooling water supply grooves are formed face each other. As the bonding treatment, for example, thermal diffusion bonding or welding is considered. By the above-described bonding treatment of the two plates, the cooling water supply groove 63 shown in fig. 10 can be formed in the electrode cooling plate 3.

(Generator base flange 8 and Cooling Water manifold 37)

Fig. 11 is a perspective view showing the configuration of the generator base flange 8. As shown in the drawing, the generator base flange 8 is formed in a substantially annular shape having a circular opening H8 at the center and 1 st and 2 nd convex regions at both ends in a plan view.

A cooling water supply groove 83 is provided inside the generator base flange 8 along the outer periphery of the opening H8. The cooling water supply tank 83 is formed by a Friction Stir Welding (FSW) or Welding processing technique.

The cooling water supply tank 83 is a tank through which cooling water flows in the generator base flange 8. The cooling water supplied through the cooling water inlet hole 84 provided in the 2 nd convex area flows along the cooling water flow path 88R on one circumferential side of the cooling water supply groove 83.

Thereafter, the cooling water is output from the cooling water inlet hole 86 provided in the 1 st projection region toward the upper cooling water manifold 37 along the flow path 89U through which the cooling water rises.

Further, the cooling water obtained from the cooling water manifold 37 flows along the cooling water descending flow path 89D toward the cooling water outlet hole 87 provided in the 1 st convex region.

Thereafter, the cooling water flows along the cooling water flow path 88L on the other circumferential side of the cooling water supply groove 83. Then, the cooling water is discharged from the cooling water outlet hole 85 provided in the 2 nd convex portion region.

Fig. 12 is a perspective view showing the configuration of the cooling water manifold 37. Fig. 13 is an enlarged explanatory view of the cooling water flow path 68 in the electrode cooling plate 3.

As shown in fig. 12, the cooling water manifold 37 has a shape conforming to the 1 st projection region (region where the cooling water inlet hole 86 and the cooling water outlet hole 87 are formed) of the generator base flange 8 in a plan view. The cooling water manifold 37 has a cooling water inlet hole 96 and a cooling water outlet hole 97 penetrating therethrough.

The cooling water supplied through the cooling water inlet hole 86 of the lower generator base flange 8 along the cooling water rising flow path 89U of each of fig. 11 to 13 is output to the upper electrode cooling plate 3 through the cooling water inlet hole 96 of the cooling water manifold 37. Then, the cooling water supplied through the cooling water inlet hole 64 of the electrode cooling plate 3 flows through the cooling water supply groove 63 along the cooling water flow path 68.

Thereafter, the cooling water flowing from the cooling water supply tank 63 is supplied to the cooling water supply tank 83 of the generator base flange 8 through the cooling water supply hole 97 of the cooling water manifold 37 and the cooling water supply hole 87 of the generator base flange 8 along the flow path 89D in which the cooling water flows down.

(Combined construction)

Fig. 14 is an explanatory diagram schematically showing a combined structure of the electrode cooling plate 3, the electrode unit cover 1, the electrode unit base 2, the cooling water manifold 37, and the generator base flange 8. Fig. 14 shows an XYZ coordinate system.

As shown in the drawing, the cooling water manifold 37 and the projection region of the electrode cooling plate 3 are disposed on the 1 st projection region of the generator base flange 8 so that the cooling water inlet hole 64 of the electrode cooling plate 3, the cooling water inlet hole 96 of the cooling water manifold 37, and the cooling water inlet hole 86 of the generator base flange 8 are aligned in a plan view.

The cooling water outlet holes 65 of the electrode cooling plate 3, the cooling water outlet holes 97 of the cooling water manifold 37, and the cooling water outlet holes 87 of the generator base flange 8 are arranged in the convex portion region 1 of the generator base flange 8 so that the cooling water outlet holes 65, 97, and 87 are aligned in a plan view.

The electrode cell cover 1 is disposed on the surface of the electrode cell base 2 so that the high-voltage via hole 41 of the electrode cell cover 1 and the high-voltage via point P1 of the electrode cell base 2 coincide with each other in a plan view. The electrode cooling plate 3 is disposed on the surface of the electrode unit cover 1 so that the high-voltage opening 61 (opening) covers the entire high-voltage via hole 41 in a plan view.

The electrode cooling plate 3 is disposed on the surface of the electrode unit base 2 such that the ground conduction groove 62 of the electrode cooling plate 3, the ground conduction hole 42 of the electrode unit cover 1, and the ground conduction point P2 of the electrode unit base 2 coincide with each other in a plan view.

(supply of raw gas)

The raw material gas supply system in the active gas generator 10 of the present embodiment having the above-described structure will be described.

The raw material gas is supplied from the outside into the housing space SP30 of the apparatus casing 30 through the gas supply flange 39 and the raw material gas supply path 33 provided on one side surface of the apparatus casing 30.

The raw material gas in the storage space SP30 is supplied to the gas flow groove 24 of the electrode unit base 2 through the gas supply hole 66 of the electrode cooling plate 3 and the gas relay hole 46 of the electrode unit cover 1.

Therefore, the raw material gas flowing in from the gas supply hole 66 and the gas relay hole 46 flows through the gas flow groove 24.

(Electrical connection between high-voltage electrode 11 and ground electrode 12)

The high voltage electrode 11 embedded in the high voltage electrode groove 21 of the electrode unit base 2 has a high voltage conduction point P1 at the center of the electrode unit base 2 as an electrical connection point.

In the active gas generator 10, the high-voltage conduction point P1, which is the 1 st conduction point of the electrode unit base 2, can be connected to the high-voltage terminal 71 via the high-voltage conduction hole 41 of the electrode unit cover 1 and the high-voltage opening 61 of the electrode cooling plate 3.

Therefore, as shown in fig. 1, the electrical connection between the high voltage terminal 71 and the high voltage electrode 11 provided at the upper portion of the device case 30 can be performed relatively easily by the electrical connection between the electrical connection point P71 of the high voltage terminal 71 and the high voltage conduction point P1 of the high voltage electrode 11 via the high voltage opening 61 of the electrode cooling plate 3 and the high voltage conduction hole 41 of the electrode unit base 2.

At this time, the opening area of the high-voltage opening 61 (opening) is sufficiently larger than the high-voltage via hole 41, and therefore, when the electrical connection between the electrical connection site P71 and the high-voltage via point P1 is achieved, the electrical connection site P71 does not contact the electrode cooling plate 3.

On the other hand, the ground electrode 12 embedded in the ground electrode groove 22 of the electrode unit base 2 has a ground conduction point P2 in the vicinity of the peripheral portion of the electrode unit base 2 as an electrical connection site.

Therefore, the electrical connection between the electrode cooling plate 3 and the ground electrode 12 can be made relatively easily by electrically connecting the ground conduction point P2 of the electrode unit base 2 and the ground conduction groove 62 of the electrode cooling plate 3 through the ground conduction hole 42 of the electrode unit cover 1.

That is, the ground conduction groove 62 and the ground conduction point P2 are connected through the ground via 42 using a ground conductive member, not shown, so that the ground conduction point P2 and the electrode cooling plate 3 can be electrically connected relatively easily.

Further, by setting the electrode cooling plate 3 having conductivity to the ground level, the ground electrode 12 can be set to the ground level at the same time.

The electrode cooling plate 3 as an electrode pressing plate is pressed from above by an elastic member such as a spring not shown. Therefore, the electrode cooling plate 3 can maintain the electrical connection between the ground conduction point P2 of the ground conductive member and the ground conduction groove 62 in a satisfactory manner by the pressing force applied from above.

Further, the electrode cooling plate 3 can stably press the electrode unit cover 1 with a pressing force applied from above.

(Cooling function of electrode Cooling plate 3)

The cooling function of the electrode cooling plate 3 will be described below with reference to fig. 1, 10 to 14.

As shown in fig. 1, a cooling water supply flange 35 is provided above the generator base flange 8. The cooling water supply flange 35 is attached to the surface of the generator base flange 8 by using attachment screws 47.

Therefore, the cooling water as the cooling medium can be supplied from the outside into the generator base flange 8 via the cooling water supply flange 35.

As shown in fig. 1 and 11, the cooling water is supplied into the cooling water supply tank 83 from a cooling water inlet hole 84 provided at a position corresponding to the water supply path of the cooling water supply flange 35 in a plan view. The cooling water flows along the cooling water flow path 88R on one circumferential side of the cooling water supply groove 83, and is output from the cooling water input hole 86 toward the cooling water manifold 37 upward along the cooling water flow path 89U.

As shown in fig. 1 and 12, the cooling water flows along the flow path 89U in which the cooling water rises, and flows toward the upper electrode cooling plate 3 via the cooling water inlet hole 96 of the cooling water manifold 37.

As shown in fig. 1, 10, and 13, the cooling water obtained from the cooling water inlet 64 flows through the annular cooling water supply tank 63 along the cooling water flow path 68, and is finally discharged from the cooling water outlet 65. The electrode cooling plate 3 can exhibit a cooling function by flowing cooling water through the cooling water supply tank 63.

The cooling water flowing through the cooling water supply tank 63 is discharged toward the cooling water manifold 37 below through the cooling water output hole 65.

Thereafter, as shown in fig. 1 and 12, the cooling water flows along the flow path 89D in which the cooling water descends, and flows toward the lower generator base flange 8 via the cooling water outlet hole 97 of the cooling water manifold 37.

As shown in fig. 1 and 11, in the generator base flange 8, the cooling water is supplied to the cooling water supply tank 83 through the cooling water outlet hole 87 along the flow path 89D in which the cooling water descends. Thereafter, the cooling water flows along the cooling water flow path 88L on the other circumferential side of the cooling water supply groove 83. Then, the coolant is discharged to the outside through a coolant drain flange, not shown, having a drain path in a region corresponding to the coolant outlet hole 85 in a plan view. Further, the cooling water drain flange is provided on the surface of the generator base flange 8 in the same manner as the cooling water supply flange 35.

Thereafter, cooling water is supplied from the outside into the generator base flange 8 through the cooling water supply flange 35 again. By flowing the cooling water through the generator base flange 8, the cooling water manifold 37, and the electrode cooling plate 3 as described above, the cooling water can be circulated through the cooling water supply groove 63 of the electrode cooling plate 3 and the cooling water can be circulated through the cooling water supply groove 83 of the generator base flange 8.

By circulating the cooling water through the cooling water supply groove 63 of the electrode cooling plate 3 in this manner, the electrode cooling plate 3 can exhibit a cooling function of cooling the electrode unit base 2 via the electrode unit cover 1.

Further, the generator base flange 8 can exhibit a cooling function of cooling the electrode unit base 2 by circulating cooling water through the cooling water supply groove 83 of the generator base flange 8.

(Effect)

The electrode unit base 2 of the active gas generator 10 of the present embodiment includes a gas flow groove 24 that is provided in a spiral shape in plan view and serves as an internal gas flow path, and a plurality of gas ejection ports 6 (at least one gas ejection port) that are provided below the discharge space so as to communicate with the gas flow groove 24.

Therefore, the active gas generator 10 of the present embodiment has an effect of effectively suppressing the phenomenon of the deactivation of the active gas because no non-discharge space that does not participate in the dielectric barrier discharge is formed between the plurality of gas ejection ports 6 and the discharge space.

Further, the above-described effects can be achieved by a relatively simple configuration in which the electrode unit base 2 is provided with the plurality of gas ejection ports 6, the high-voltage electrode 11, the ground electrode 12, and the gas flow grooves 24, the electrode unit cover 1 is provided with the high-voltage via hole 41, the ground via hole 42, and the gas relay hole 46, and the electrode cooling plate 3 is provided with the high-voltage opening 61, the ground via groove 62, and the gas supply hole 66. Therefore, the device configuration of the active gas generator 10 can be simplified.

In the active gas generator 10, the gas flow groove 24 is provided in a spiral shape in a plan view. Therefore, the active gas can be ejected from the plurality of gas ejection ports 6 in a state of saturated gas concentration without increasing the area of the electrode unit base 2 itself, and the device can be downsized accordingly.

Further, the electrode cell cover 1 in the active gas generator 10 has the high-voltage via hole 41 and the ground via hole 42 which are provided in the regions coinciding with the high-voltage via point P1 and the ground via point P2 in a plan view and which penetrate therethrough, respectively.

Therefore, the electrode cell cover 1 can close the upper side of the electrode cell base 2 while ensuring the function of electrically connecting the high-voltage conduction point P1 and the ground conduction point P2 to the outside via the high-voltage conduction hole 41 and the ground conduction hole 42.

The electrode cooling plate 3 as the electrode pressing plate has a high-voltage opening 61 as an opening, and when the electrode cooling plate 3 is disposed on the electrode unit cover 1, the high-voltage opening 61 covers the high-voltage via hole 41 of the electrode unit cover 1 in a plan view and has a shape wider than the high-voltage via hole 41.

Therefore, the electrode cooling plate 3 can secure the function of electrically connecting the high-voltage conduction point P1 through the high-voltage via hole 41 to the external high-voltage terminal 71, and can electrically connect the ground conduction point P2 to itself through the ground via hole 42.

Further, the electrode cooling plate 3 that presses the electrode unit cover 1 with the pressing force applied from above can stably press the electrode unit cover 1.

In the active gas generator 10 of the present embodiment, the high-voltage electrode 11 and the ground electrode 12 are disposed in the electrode unit 100 such that the ground electrode 12 is located on the outermost periphery of the electrode unit base 2 in a plan view.

Therefore, the ground electrode 12 on the outer periphery of the high-voltage electrode 11 can necessarily absorb the electric field vector from the high-voltage electrode 11 to which a high voltage is applied toward the outer periphery of the electrode unit base 2.

Further, the active gas generator 10 can cool the electrode unit base 2 via the electrode unit cover 1 by the cooling function of the electrode cooling plate 3, and can remove heat from the electrode unit base 2.

In addition, in the active gas generator 10 of the present embodiment, the electrode cooling plate 3, the electrode unit cover 1, the electrode unit base, and the cooling medium circulation mechanism (the cooling water manifold 37+ the generator base flange 8) are integrally connected by the mounting screws 48, so that the active gas generator 10 can be downsized.

Although the present invention has been described in detail, the above description is illustrative in all aspects, and the present invention is not limited thereto. Numerous modifications, not illustrated, can be conceived without departing from the scope of the invention.

Description of the symbols

1 electrode unit cover

2 electrode unit base

3 electrode cooling plate

6 gas jet

8 Generator base flange

10 active gas generating device

11 high voltage electrode

12 ground electrode

21 tank for high-voltage electrode

22 ground electrode tank

24 gas circulation groove

30 device case

37 cooling water manifold

41 high pressure via

42 ground via

46 gas relay hole

61 high pressure opening part

62 ground connection conduction groove

63, 83 cooling water supply tank

66 gas supply hole

71 high-voltage terminal

P1 high voltage conduction point

P2 ground conduction point