Radical emission mechanism, and surface treatment apparatus equipped therewith

Abstract

The present invention provides a surface treatment apparatus and a surface treatment method for efficiently performing surface treatment under atmospheric pressure without damaging the substrate. [Solution] The radical gas release mechanism activated under atmospheric pressure comprises a first electrode, a plurality of second electrodes arranged at intervals and extending in one direction, each electrically conductive to the others, and a cover that covers a plurality of second electrodes and is positioned to close the opening portion of the groove sandwiched between adjacent second electrodes, on the side opposite to the first electrode. Each of the plurality of holes extending in one direction surrounded by the first electrode, adjacent second electrodes, and cover is a gas channel through which gas flows in from one end and activated radical gas is released from the other end. The portion of the first electrode and / or second electrode facing the gas channel is covered with a dielectric. The first electrode and the second electrode are configured such that one is a ground electrode and the other is a driving electrode, activating the gas flowing through the gas channel to create a radical gas.

Description

Technical Field

[0001] The present invention relates to a radical emission mechanism for efficiently generating radicals under atmospheric pressure without damaging a substrate, and a surface treatment apparatus provided with the same.

Background Art

[0002] For the purpose of surface modification and microfabrication of various substrates, surface treatment techniques using energy sources such as light, heat, and plasma are utilized. Among surface treatment techniques, a remote atmospheric pressure plasma treatment technique (hereinafter referred to as remote surface treatment) that separates an electrode and a substrate and supplies a gas (radical) activated by an energy source to the substrate surface for treatment has the characteristic that the energy source is not directly exposed to the substrate surface, so it is difficult to receive substrate damage such as alteration due to heat, charging of the substrate, and damage due to discharge associated therewith. Therefore, it is often used as a surface treatment technique for low melting point substrates and electronic devices. In general remote surface treatment, a high voltage is applied between a pair of electrodes to ionize the gas between the electrodes to generate plasma, and the treatment is performed by exposing the substrate to the gas activated by the plasma. However, when the distance between the substrate and the electrode to which a high voltage is applied becomes close, there is a concern about substrate damage due to abnormal discharge. Conversely, if the substrate is separated too far from the electrode, the activated gas is deactivated before reaching the substrate, and there is a problem that efficient treatment cannot be performed. Therefore, methods and apparatuses for suppressing substrate damage by reducing the applied voltage required for stable discharge using surface discharge have been proposed so far.

[0003] For example, Patent Document 1 and Patent Document 2 disclose a structure in which a surface discharge electrode is arranged on a wall surface to completely separate the substrate and the discharge space in a remote atmospheric pressure plasma treatment method. Thereby, it is disclosed that damage to the substrate can be suppressed because the substrate is not directly exposed to the plasma.

Prior Art Documents

Patent Documents

[0004] [Patent Document 1] Japanese Patent Publication No. 2005-50723 [Patent Document 2] Japanese Patent Publication No. 2014-173130 [Overview of the Initiative] [Problems that the invention aims to solve]

[0005] However, in the surface treatment method under atmospheric pressure disclosed in Patent Document 1, the cross-sectional area of ​​the gas flow path is large relative to the glow discharge generation area, which can reduce the gas decomposition efficiency and thus the treatment efficiency. Furthermore, in the atmospheric pressure plasma generator disclosed in Patent Document 2, since surface discharge rather than dielectric barrier discharge is used, a stable discharge cannot be obtained, and there are concerns about substrate damage due to abnormal discharge because both electrodes are exposed in the discharge space.

[0006] The present invention has been made in view of the above-mentioned problems, and provides a radical emission mechanism that can perform surface treatment on a substrate with high efficiency under atmospheric pressure while suppressing damage to the substrate by further narrowing the discharge space in addition to using surface discharge, thereby lowering the discharge voltage, and a surface treatment apparatus equipped therewith. [Means for solving the problem]

[0007] [1] The radical release mechanism of the present invention, which solves the above problems, is a mechanism for releasing a radical gas activated under atmospheric pressure, The first electrode and A plurality of electrodes extending in one direction are arranged at intervals and placed on one side of the first electrode via a dielectric, and each of these electrodes is electrically conductive to the others. It comprises a lid that covers a plurality of the second electrodes, which is positioned to close the opening portion of the groove sandwiched between adjacent second electrodes, on the side opposite to the first electrode, Each of the multiple holes extending in one direction, surrounded by the first electrode, the adjacent second electrode, and the cover, is a gas channel through which gas flows in from one end and activated radical gas is released from the other end. The portion of the first electrode and / or the second electrode facing the gas flow path is covered with a dielectric material. The first electrode and the second electrode described above have one being a ground electrode and the other a driving electrode, and they activate the gas flowing through the gas channel to turn it into a radical gas.

[0008] The radical release mechanism of the present invention is preferably in any of the following forms [2] to

[10] . [2] The radical emission mechanism of [1], wherein the portion of the first electrode facing the gas flow path is covered with a dielectric material. [3] The radical emission mechanism according to [1] or [2], wherein the portion of the second electrode facing the gas flow path is covered with a dielectric. [4] A radical emission mechanism according to any of [1] to [3] above, wherein the second electrode is the comb-toothed portion of a plate-like body on which comb teeth are formed. [5] A radical emission mechanism according to any of [1] to [4] above, wherein the second electrode and the cover are electrically conductive and each is part of a single conductor. [6] The radical emission mechanism of [5], wherein the portion of the second electrode and the cover facing the gas flow path is covered with a dielectric. [7] A radical emission mechanism according to any of [1] to [6] above, wherein the first electrode is recessed in the portion along the gas flow path. [8] A radical emission mechanism according to any of [1] to [7] above, wherein the cover covers the plurality of second electrodes via a dielectric and is electrically conductive with the first electrode.

[0009] [9] The above-mentioned cover is referred to as the first cover, and the above-mentioned gas flow path is referred to as the first gas flow path. A plurality of electrodes extending in one direction are arranged at intervals and separated on the other side of the first electrode via a dielectric, each of which is electrically conductive to the others, and a third electrode is electrically conductive to the first electrode and extends in the same direction as the first electrode. It comprises a second cover body that covers a plurality of third electrodes, which is positioned to close the opening portion of the groove sandwiched between adjacent third electrodes, on the side opposite to the first electrode, Each of the multiple holes extending in one direction, surrounded by the first electrode, the adjacent third electrode, and the second cover, is a second gas flow path through which gas flows in from one end and activated radical gas is released from the other end. The portion of the first electrode and / or the third electrode facing the second gas flow path is covered with a dielectric material. The first electrode and the third electrode activate the gas flowing through the second gas channel to convert it into a radical gas. One of the radical release mechanisms described in [1] to [8] above.

[10] The radical emission mechanism according to [9], wherein the first gas flow path and the second gas flow path are arranged in a staggered pattern when viewed from the direction in which the first gas flow path and the second gas flow path extend.

[0010]

[11] The surface treatment apparatus of the present invention that solves the above problems is A radical release mechanism in any of the above [1] to

[10] , The device includes a substrate holding mechanism for holding a substrate that is positioned in a space separated from the radical release mechanism, in a direction from which the radical gas is released from the radical release mechanism. [Effects of the Invention]

[0011] According to the radical emission mechanism and surface treatment apparatus equipped therewith of the present invention, by using surface discharge and further narrowing the discharge space, the discharge voltage can be reduced, thereby suppressing damage to the substrate and enabling highly efficient surface treatment of the substrate under atmospheric pressure. [Brief explanation of the drawing]

[0012] [Figure 1] Figure 1 is a schematic diagram showing an example of a radical emission mechanism according to the first embodiment of the present invention. [Figure 2] Figure 2 is a schematic diagram showing an example of the shape when the radical emission mechanism according to the first embodiment of the present invention is viewed from the radical emission port. [Figure 3] Figure 3 is a perspective view showing an example of the shape of an electrode portion having a driving electrode with a comb tooth structure of a plate-like body and a dielectric according to the first embodiment of the present invention. [Figure 4] Figure 4 is a schematic diagram showing an example of a radical emission mechanism according to the second embodiment of the present invention. [Figure 5] Figure 5 is a schematic diagram showing an example of the shape when the radical emission mechanism according to the second embodiment of the present invention is viewed from the radical emission port. [Figure 6] Figure 6 is a schematic diagram showing an example of the shape when the radical emission mechanism according to the third embodiment of the present invention is viewed from the radical emission port. [Figure 7] Figure 7 is a schematic diagram showing an example of the shape when the radical emission mechanism according to the fourth embodiment of the present invention is viewed from the radical emission port. [Figure 8] Figure 8 is a schematic diagram showing an example of the shape when the radical emission mechanism according to the fifth embodiment of the present invention is viewed from the radical emission port. [Figure 9] Figure 9 is a schematic diagram showing the shape when the radical emission mechanism of the comparative example is viewed from the radical emission port.

Mode for Carrying Out the Invention

[0013] [First Embodiment of the Surface Treatment Apparatus] Hereinafter, examples of embodiments of the present invention will be described with reference to the drawings. Figure 1 is a schematic diagram showing a radical emission mechanism for generating radicals in an atmospheric pressure atmosphere of the present invention. As shown in Figure 1, the first embodiment includes a radical emission mechanism 101 and a substrate holding mechanism 10.

[0014] Referring to Figure 1, the radical release mechanism 101 will be described. The radical release mechanism 101 is a mechanism that releases radicals, which are the decomposition products of a gas, to the outside through a radical release port 2 after energy has been supplied to the gas in an atmospheric pressure atmosphere. A substrate holding mechanism 10 is provided at a position opposite the radical release port 2, separated by space from the radical release mechanism 101. By holding the substrate 11 in the substrate holding mechanism 10 and keeping it stationary or transporting it, continuous surface treatment can be performed. Alternatively, the substrate 11 may be placed alone without being held in the substrate holding mechanism 10. In addition, the flow rate of the gas supplied to the gas flow path 4 is adjusted using a gas flow rate adjustment mechanism 12. A mass flow controller or a gas flow control valve can be used as the gas flow rate adjustment mechanism 12.

[0015] Next, refer to Figure 2. Figure 2 is a schematic diagram of the radical emission mechanism 101 in this embodiment as seen from the radical emission port 2 side. The radical emission mechanism 101 has a ground electrode 5 which is a first electrode, a dielectric 6 that covers the ground electrode 5, a plurality of second electrodes, which are drive electrodes 7, that are spaced apart and extend in one direction (extending in the direction toward the back of the paper), and a cover 3. The space enclosed by the ground electrode 5, drive electrodes 7, and cover 3, which are covered by the dielectric 6, forms a plurality of gas flow paths 4 that communicate with the radical emission port 2. The drive electrodes 7 are connected to a power supply 8. Note that the electrode labeled 5 may be the drive electrode and the electrode labeled 7 may be the ground electrode. The housing 9 is provided to hold the cover 3, ground electrode 5, drive electrodes 7, etc.

[0016] The drive electrode 7 is arranged on one side of the ground electrode 5 via a dielectric 6, and consists of multiple electrodes extending in one direction, spaced apart from each other, and each is electrically conductive. The drive electrode 7 may also be coated with a dielectric.

[0017] Next, refer to Figure 3. Figure 3 is a perspective view of the ground electrode 5, dielectric 6, and drive electrode 7. As shown in Figure 3, the comb-toothed portion of the plate-like body has comb teeth formed on it, which serves as the drive electrode 7. This makes it easy to electrically connect multiple drive electrodes 7.

[0018] Refer to Figure 2 again. The gas channel 4 is the space surrounded by the lid 3, the dielectric 6, and the drive electrode 7. Within the gas channel 4, a surface discharge type dielectric barrier discharge occurs between the ground electrode 5 and the drive electrode 7 via the dielectric 6, causing the gas to decompose and become a radical gas. It is preferable that the surface discharge type dielectric barrier discharge is generated along the entire longitudinal direction of the gas channel 4 to improve the gas decomposition efficiency, but it may be generated only in a part of it. Furthermore, in order to suppress the deactivation of the radical gas during the time it passes through the gas channel 4, it is preferable that the surface discharge type dielectric barrier discharge is generated in the region close to the radical outlet 2. In this embodiment of Figure 3, the portion of the ground electrode 5 facing the gas channel 4 is covered with the dielectric 6, but the portion of the drive electrode 7 facing the gas channel 4 may also be covered with the dielectric 6, and the portions of the ground electrode 5 and the drive electrode 7 facing the gas channel 4 may each be covered with the dielectric 6.

[0019] The cross-sectional shape of the gas channel 4 is not particularly limited, but it is preferable to reduce the cross-sectional area of ​​the gas channel 4 in order to increase the area occupied by the surface discharge type dielectric barrier discharge relative to the cross-sectional area of ​​the gas channel 4 and improve the gas decomposition efficiency. 2 By reducing the size to such an extent, and efficiently supplying charged particles into the space, it is possible to generate a surface discharge type dielectric barrier discharge at the wall surface of the gas channel as shown in Patent Document 1, and compared to a structure that widens the channel cross-sectional area by not dividing the discharge space into multiple channels, it is expected that the discharge initiation voltage and discharge maintenance voltage will be further reduced. In addition, the number of gas channels 4 can be arbitrarily selected. Furthermore, the cross-sectional shape of the driving electrode 7 is not particularly limited, but in the case of the comb-tooth structure in Figure 3, where abnormal discharge is likely to occur at the corners of the electrode, for example, it is preferable that the corners 71 of the comb-shaped electrode do not face the gas channel 4 which is the discharge space, and that the dielectric 6 is arranged without leaving a space between it and the electrode. Moreover, it is even more preferable that the cross-section of the teeth of the comb-shaped electrode is circular or the like, without corners.

[0020] The material and thickness of the dielectric 6 are not particularly limited, as long as it has a dielectric strength higher than the voltage applied between the ground electrode 5 and the drive electrode 7. However, it is more preferable to use a material with a high dielectric constant, as this increases the amount of charged particles that can be accumulated in the dielectric 6 and allows for more efficient radical generation. Examples include rubbers such as silicone rubber, ceramics such as titanium oxide, and glass. Since power supply 8 needs to generate dielectric barrier discharge, it can be selected from AC power supplies or pulse power supplies. In this invention, "AC" refers to a power supply in which the magnitude of voltage and current values ​​changes over time. Generally, the values ​​change sinusoidally over time, but other examples include those that change in a square wave shape. In this invention, "pulse" refers to a power supply in which the magnitude of voltage and current values ​​changes rapidly over a short period of time. Specifically, this includes, but is not limited to, waveforms such as square waves, triangular waves, and sawtooth waves. A pulse is characterized by having a constant time width and abrupt rising and falling edges. The frequency of the power supply is not particularly specified, but examples include low frequencies on the order of several kHz, high frequencies on the order of tens of MHz, and microwaves on the order of several GHz. In the electrodes of this invention using creepage discharge type dielectric barrier discharge, the voltage required to maintain stable discharge is lower than that of electrodes using parallel plate type dielectric barrier discharge with a distance of several mm between the pair of electrodes, so a wider range of power supplies can be selected.

[0021] The radical emission mechanism 101 preferably includes measuring instruments for monitoring the energy state and radical generation state within the radical generation space. By including these measuring instruments, abnormalities during surface treatment can be detected early. For example, by including an emission spectrometer capable of measuring the plasma emission state, the plasma energy and the amount of excited species can be determined from the emission peak and emission wavelength. Furthermore, the amount of radicals can be measured by installing a radical monitor. These measuring instruments can be appropriately changed depending on the object to be monitored, even if they are not listed above.

[0022] The gas supplied to the gas channel 4 can be appropriately selected according to the purpose of the surface treatment, such as surface modification or thin film formation. Examples include inert gases such as argon, helium, and nitrogen; non-polymerizable reactive gases such as oxygen and water vapor; and polymerizable reactive gases such as methane and hexamethyldisiloxane. Furthermore, two or more different gases may be mixed.

[0023] In this invention, "atmospheric pressure" refers to the gas pressure in an open space that is not intentionally controlled by a vacuum pump or the like, and is what is commonly known as normal pressure. Cases where harmful substances are drawn in by a local exhaust ventilation system to remove them from a space that is not airtight are included in atmospheric pressure.

[0024] Furthermore, "radical" refers to an active species, specifically an atom or molecule with highly reactive unpaired electrons, or an atom or molecule in an excited state.

[0025] In this invention, "surface discharge type dielectric barrier discharge" is a type of dielectric barrier discharge, which is a glow discharge that occurs between a pair of electrodes in contact via a dielectric. In this embodiment, a discharge occurs inside the gas channel 4 between the ground electrode 5 and the drive electrode 7, which are covered with a dielectric 6. In this method, plasma can be generated at a lower voltage compared to the parallel plate type dielectric barrier method, where the distance between the pair of electrodes is several millimeters, thus reducing the risk of abnormal discharge and enabling stable radical generation. Furthermore, because the distance between the ground electrode 5 and the drive electrode 7 can be reduced, the electric field strength between the ground electrode 5 and the drive electrode 7 can be increased, generating a high-density plasma in the radical gas channel 4. This allows for the generation of more radicals, thereby accelerating surface treatment.

[0026] In the present invention, "parallel plate dielectric barrier discharge" refers to a glow discharge that occurs in the space between two electrodes (a driving electrode and a ground electrode) that are arranged parallel to each other with space between them, and at least one of their surfaces is covered with a dielectric material.

[0027] [Second embodiment of surface treatment apparatus] Figure 4 is a schematic diagram showing the radical emission mechanism that generates radicals under atmospheric pressure in the second embodiment. As shown in Figure 4, the second embodiment includes a radical emission mechanism 201 and a substrate holding mechanism 10. Figure 5 is a schematic diagram of the radical emission mechanism 201 in the second embodiment of the present invention as seen from the radical emission port 2 side. In addition to the features of the first embodiment, the second embodiment has two sets of drive electrodes 7 and dielectrics 6 arranged.

[0028] Specifically, on the side opposite to the side where the second electrode 7 is located, flanking the first electrode 5, there is a dielectric 6 covering the first electrode 5, multiple third electrodes 7' arranged at intervals and extending in one direction (towards the back in the plane of the paper in Figure 5), and a second cover 3'. The space enclosed by the first electrode 5, the third electrodes 7', and the second cover 3', all covered by the dielectric 6, forms multiple second gas channels 4'. Each of the multiple third electrodes 7' is electrically conductive and is electrically conductive with the second electrode 7, acting as a driving electrode. Furthermore, the third electrodes 7' extend in the same direction as the second electrode 7.

[0029] With this configuration, the radical gases released from the gas channel 4 formed by the second electrode (driving electrode) 7 (hereinafter sometimes referred to as the first gas channel 4) and the second gas channel 4' formed by the third electrode (driving electrode) 7' merge in the area between the ground electrode 5 and the substrate holding mechanism 10. As a result, the diffusion of radical gases in this area is suppressed and they remain there compared to the first embodiment. This suppresses contact between the radical gases and the atmosphere in the space between the substrate holding mechanism 10 and the radical release mechanism 201, thereby suppressing the deactivation of the radical gases. Therefore, the concentration of radical gases can be increased, and processing can be performed more efficiently.

[0030] The number of drive electrodes 7(7'), dielectrics 6, and ground electrodes 5 can be arbitrarily selected. It is preferable to arrange an appropriate number of ground electrodes 5, dielectrics 6, and drive electrodes 7(7') so as to increase the surface discharge type dielectric barrier discharge portion. The total cross-sectional area of ​​the gas channels 4(4') of the radical emission mechanism 201 can be increased while maintaining the proportion of the surface discharge type dielectric barrier discharge relative to the cross-sectional area of ​​each gas channel 4(4'), allowing more gas to flow. This increases the absolute amount of activated radicals released from the radical emission port, enabling more efficient processing.

[0031] Note that the electrode labeled 5 may be the driving electrode and the electrode labeled 7(7') may be the ground electrode. Also, the dielectric 6 may cover the portion of the driving electrode 7(7') facing the gas flow path 4(4') rather than the portion of the ground electrode 5 facing the gas flow path 4(4'), or it may cover the portions of both the ground electrode 5 and the driving electrode 7(7') facing the gas flow path 4(4'). The same applies to the third, fourth, and fifth embodiments described below.

[0032] Furthermore, the first gas channel 4 and the second gas channel 4' may be arranged alternately in a staggered pattern. This allows the gas channels to be uniformly arranged as a whole in the longitudinal direction, resulting in a more uniform processing effect.

[0033] [Third Embodiment of Surface Treatment Device] Figure 6 is a schematic diagram of the radical emission mechanism 301 in the third embodiment of the present invention, viewed from the radical emission port 2 side. In addition to the features of the first embodiment, the third embodiment makes the portion that was a cover 3 in the first embodiment a conductor electrically connected to the drive electrode 7, so that the portion of the cover 3 also electrically becomes a drive electrode 7. As a result, depending on the applied voltage, a parallel plate type dielectric barrier discharge can be generated between the drive electrode 7 in the portion facing the ground electrode 5, and since the discharge portion spreads throughout the gas flow path 4, an improvement in gas decomposition efficiency can be expected.

[0034] [Fourth Embodiment of Surface Treatment Device] Figure 7 is a schematic diagram of the radical emission mechanism 401 in the fourth embodiment of the present invention, viewed from the radical emission port 2 side. In addition to the features of the third embodiment, the fourth embodiment has a recessed structure in the portion of the ground electrode 5 along the gas flow path 4. As a result, the cross-sectional area of ​​the gas flow path 4 can be increased compared to the third embodiment, the absolute amount of activated radicals emitted from the radical emission port can be increased, and processing can be performed more efficiently.

[0035] [Fifth Embodiment of Surface Treatment Device] Figure 8 is a schematic diagram of the radical emission mechanism 501 in the fifth embodiment of the present invention, viewed from the radical emission port 2 side. In addition to the features of the first embodiment, the fifth embodiment has a dielectric 6 and a ground electrode 5 arranged via the dielectric 6 so as to sandwich the gas flow path 4. In the fifth embodiment, one side of the dielectric 6 plays the same role as the cover 3. The portion of the drive electrode 7 that contacts the ground electrode 5 via the dielectric 6 is doubled, and the portion where surface discharge type dielectric barrier discharge is generated increases. Specifically, in the first embodiment, when the radical emission mechanism 101 is viewed from the radical emission port 2 side, surface discharge type dielectric barrier discharge is generated in two locations for one radical gas flow path 4, but in this embodiment, it is generated in twice as many locations, four locations. As a result, the proportion of the portion where surface discharge type dielectric barrier discharge is generated relative to the cross-sectional area of ​​the radical gas flow path 4 increases, and the gas decomposition efficiency can be improved. [Examples]

[0036] The surface treatment apparatus of the present invention will be described in the following examples, but the present invention is not limited to these examples.

[0037] [Example 1] The radical emission mechanism 101 and substrate holding mechanism 10 of the first embodiment shown in Figure 1 were used. In this apparatus, an electric single-axis stage was used for the substrate holding mechanism 10, and a PET film (Toray Industries, Inc.'s "Lumirror" T60) was used for the substrate 11.

[0038] The radical emission mechanism 101 was positioned facing the substrate 11 so that the distance between the radical emission port 3 and the substrate 11 was 10 mm. The radical gas flow path 4 was shaped as a square with sides of 2 mm and a width of 100 mm, as shown in Figure 2. Gas was supplied to the radical emission mechanism 101 while adjusting the nitrogen flow rate to 30 L / min using the gas flow rate adjustment mechanism 12.

[0039] A high-voltage power supply 8 was used, applying a sinusoidal AC voltage with a frequency of 5 kHz and a voltage of 7.5 kVpp. Surface treatment was performed while the motorized single-axis stage, which is the substrate holding mechanism 10, was transported at 0.2 m / min. As an indicator of the surface treatment effect, the surface treatment effect of the substrate 11 after surface treatment was evaluated using a contact angle meter (DMs-401, manufactured by Kyowa Interface Science Co., Ltd.) to measure the contact angle with pure water. The average contact angle of 5 points was 60.8°. For reference, the contact angle of the untreated PET film substrate 11 was 70.6°.

[0040] [Comparative Example 1] Figure 9 is a schematic diagram of a radical emission mechanism 601 using a parallel-plate dielectric barrier discharge. In this comparative example 1, a parallel-plate dielectric barrier discharge is generated in a gas channel 4 between a ground electrode 5 covered with a dielectric 6 and a drive electrode 7 positioned with space between them, thereby generating radicals. There is only one gas channel 4, and its opening is 1 mm in the direction between electrodes and 100 mm in the direction parallel to the electrodes. The procedure was carried out in the same manner as in Example 1, except that the voltage applied to the electrodes using a power supply 8 was set to 15.0 kV pp. The contact angle of pure water was evaluated, and the average contact angle was 64.8°.

[0041] [Example 2] Except for the following changes, the same surface treatment apparatus and surface treatment conditions as in Example 1 were used. The shape of the radical gas channel 4 was set to a square with sides of 1 mm. The voltage applied by the power supply 8 was set to an AC pulsed voltage with a frequency of 250 kHz and a power of 560 W. As a result of evaluating the contact angle of pure water, the average contact angle of 5 points was 56.9°, and the standard deviation was 8.1.

[0042] [Example 3] Except for the following changes, the same surface treatment apparatus and surface treatment conditions as in Example 2 were used. The voltage applied by power supply 8 was set to a pulsed AC voltage with a power of 280W. Gas was supplied to the radical emission mechanism 101 while adjusting the nitrogen flow rate to 15 L / min using the gas flow rate adjustment mechanism 12, and a second treatment was performed under the same conditions after a 25-second interval following the first treatment. As a result of evaluating the contact angle of pure water, the average contact angle of 5 points was 53.6°, and the standard deviation was 4.3.

[0043] [Example 4] The radical emission mechanism 201 and substrate holding mechanism 10 of the second embodiment shown in Figures 4 and 5 were used. As shown in Figure 2, the radical gas channel 4 was a square with sides of 1 mm, and the first gas channel 4 and the second gas channel 4' located on either side of the ground electrode 5 were arranged alternately in a staggered pattern. Except for these, the surface treatment apparatus configuration and surface treatment conditions were the same as in Example 2. As a result of evaluating the contact angle of pure water, the average contact angle of 5 points was 41.6°, and the standard deviation was 4.7.

[0044] [Example 5] Except for the following changes, the surface treatment was carried out using the same surface treatment apparatus and surface treatment conditions as in Example 4. Gas was supplied to the radical release mechanism 201 while adjusting the nitrogen flow rate to 60 L / min. As a result of evaluating the contact angle of pure water, the average contact angle of 5 points was 32.3°, with a standard deviation of 1.3. [Industrial applicability]

[0045] By using the surface treatment apparatus of the present invention, surface treatment can be efficiently performed under atmospheric pressure while suppressing substrate damage caused by high voltage. This apparatus can be used, for example, for cleaning, surface modification, and film formation of substrates, but its range of applications is not limited to these. [Explanation of Symbols]

[0046] 101, 201, 301, 401, 501 Radical release mechanism 601 Conventional Radical Emission Mechanism 2 Radical emission ports 3. Lid (First Lid) 3' Second lid 4. Gas flow path (first gas flow path) 4' Second gas channel 5. First electrode (ground electrode) 6 Dielectrics 7. Second electrode (driving electrode) 7' Third electrode (driving electrode) 8 Power supply 9 cabinets 10 Substrate holding mechanism 11 Base material 12. Gas flow rate adjustment mechanism 71 Corner of comb-shaped electrode

Claims

1. A mechanism for releasing radical gas activated under atmospheric pressure, The first electrode and A plurality of electrodes extending in one direction are arranged at intervals and separated on one side of the first electrode via a dielectric, and each of these electrodes is electrically conductive to the others. It comprises a lid that covers a plurality of the second electrodes, which is positioned to close the opening portion of the groove sandwiched between adjacent second electrodes, on the side opposite to the first electrode, Each of the multiple holes extending in one direction, surrounded by the first electrode, the adjacent second electrode, and the cover, is a gas channel through which gas flows in from one end and activated radical gas is released from the other end. The portion of the first electrode and / or the second electrode facing the gas flow path is covered with a dielectric material. The first electrode and the second electrode are configured such that one is a ground electrode and the other is a driving electrode, and they activate the gas flowing through the gas channel to create a radical gas. Radical release mechanism.

2. The radical emission mechanism according to claim 1, wherein the portion of the first electrode facing the gas flow path is covered with a dielectric material.

3. The radical emission mechanism according to claim 1, wherein the portion of the second electrode facing the gas flow path is covered with a dielectric material.

4. The radical emission mechanism according to claim 1, wherein the second electrode is the comb-tooth portion of a plate-shaped body on which comb teeth are formed.

5. The radical emission mechanism according to claim 1, wherein the second electrode and the cover are electrically conductive and each is part of a single conductor.

6. The radical emission mechanism according to claim 5, wherein the portion of the second electrode and the cover facing the gas flow path is covered with a dielectric material.

7. The radical emission mechanism according to claim 1, wherein the first electrode is recessed in the portion along the gas flow path.

8. The radical emission mechanism according to claim 1, wherein the cover covers the plurality of second electrodes via a dielectric and is electrically conductive with the first electrode.

9. The cover is referred to as the first cover, and the gas flow path as the first gas flow path. A plurality of electrodes extending in one direction are arranged at intervals on the other side of the first electrode via a dielectric, each of which is electrically conductive to the others, and a third electrode is electrically conductive to the first electrode and extends in the same direction as the first electrode. It comprises a second cover body that covers a plurality of the third electrodes, positioned to close the opening portion of the groove sandwiched between adjacent third electrodes, on the side opposite to the first electrode, Each of the multiple holes extending in one direction, surrounded by the first electrode, the adjacent third electrode, and the second cover, is a second gas flow path through which gas flows in from one end and activated radical gas is released from the other end. The portion of the first electrode and / or the third electrode facing the second gas flow path is covered with a dielectric material. The first electrode and the third electrode activate the gas flowing through the second gas channel to convert it into a radical gas. The radical release mechanism according to claim 1.

10. The radical emission mechanism according to claim 9, wherein, when viewed from the direction in which the first gas flow path and the second gas flow path extend, the first gas flow path and the second gas flow path are arranged in a staggered pattern.

11. A radical release mechanism according to any one of claims 1 to 10, A substrate holding mechanism for holding a substrate positioned in a space separated from the radical emission mechanism, in a direction from which the radical gas is emitted from the radical emission mechanism, A surface treatment apparatus having

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