JP2018185958A - Surface treatment device and surface treatment method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a surface treatment device and a surface treatment method capable of improving surface treatment speed, by reducing loss amount due to adhesion of active species or deposition species on the peripheral wall surface constituting an electrode, and by increasing supply amount of active species or deposition species for the treatment surface of a base material.SOLUTION: A surface treatment device for treating the surface of a base material includes: a vacuum vessel; exhaust means for depressing the vacuum vessel, and maintaining that pressure; plasma generation means provided in the vacuum vessel, and generating plasma; a base material holding mechanism for holding a base material, and placed so that the treatment surface of the base material faces a plasma generation space where plasma is generated by the plasma generation means; and a peripheral wall surrounding the plasma generation space and the base material holding mechanism. In the peripheral wall, multiple first gas supply ports for blowing gas in oblique direction to the wall surface of the peripheral wall, toward a space surrounded by the peripheral wall, are formed.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a surface treatment apparatus and a surface treatment method.

  Surface treatment using plasma is widely used for surface modification and fine processing of various substrates. This is because the plasma is generated by ionizing the plasma excitation gas, and charged particles (ions and electrons) and radicals, functional groups, and other active species in the generated plasma and film formation species generated by decomposition of the polymerizable gas Is exposed to the surface of the substrate according to the purpose of the surface treatment.

  As an example of surface treatment using plasma, the charged particles generated by ionizing the plasma excitation gas collide with the substrate surface to form a fine shape, or by bonding functional groups to the substrate surface. Surface modification that imparts functions such as hydrophilicity and oil repellency, and also decomposes the polymerizable gas using radicals and charged particles, and chemically forms the film-forming species generated by decomposing the polymerizable gas on the treated surface of the substrate. Development of various surface treatment apparatuses such as CVD for forming thin films by mechanically bonding has been advanced.

  In order for these surface treatments to proceed at high speed, the amount of film-forming species generated by decomposition of active species such as charged particles and radicals generated by ionizing the plasma excitation gas and radicals and polymerizable gas is increased. It is necessary to promote the reaction by supplying them to the treated surface of the substrate and the reaction space with the polymerizable gas without waste. As an effort to increase the processing speed, in the process of transporting the generated active species and film-forming species to the substrate surface, the amount of active species and film-forming species that adhere to the electrode member surface and are lost is reduced. Measures for improving the supply amount of active species and film-forming species to the treatment surface of the substrate and the reaction space with the polymerizable gas have been studied.

  For example, in Patent Document 1, an alumina casing having low reactivity with CFn ions and radicals is provided inside the wall of the vacuum chamber, so that the collided CFn ions and radicals react inside the chamber wall and disappear. It has been shown that the amount of active species can be reduced. It is said that uniform and high-speed processing can be performed by transporting the generated CFn ions and radicals to the processing surface of the substrate without annihilation.

  Further, in Patent Document 2, an adhesion suppression gas supplied from a plurality of discharge ports distributed two-dimensionally on a wall surface surrounding a processing space of a peripheral wall that defines a CVD processing space is generated by decomposition of a polymerizable gas. It has been shown that by colliding with the film type and changing the direction, the collision of the film-forming species with the wall surface surrounding the processing space of the peripheral wall that defines the processing space can be suppressed. It is said that the frequency of cleaning the peripheral wall and the amount of cleaning gas used during cleaning can be reduced. In this patent document 2, the film-forming species that no longer collides with the peripheral wall will fly toward the exhaust port, the substrate surface, and the electrode surface, and a part will be used for processing the substrate. It is considered that the supply amount of the film-forming species to the treated surface of the base material increases secondaryly, so that the speed of the surface treatment can be expected.

JP-A-9-55368 Japanese Patent Laying-Open No. 2015-170680

  However, in the method of Patent Document 1, since the collision of the active species with the casing itself cannot be reduced, sputtering occurs due to the active species that collided with the casing used to reduce the reaction of the active species on the inner wall of the chamber. Fine particles are scattered from the housing and adhere to and mix with the treated substrate, leading to a reduction in the quality of the surface-treated substrate.

  In the method of Patent Document 2, the deposition type flying in a space other than the front direction of the discharge port cannot be pushed back. For this reason, the film-forming species flying between the discharge ports collide with and adhere to the electrode member surface and the inner wall of the chamber and disappear. I can not expect.

  The object of the present invention is to reduce the loss due to adhesion of active species and film-forming species on the surface of the peripheral wall constituting the electrode, increase the supply amount of active species and film-forming species to the substrate surface, and increase the surface treatment speed. An object of the present invention is to provide a surface treatment apparatus and a surface treatment method that can be improved.

  In order to solve the above-described problems, the present invention provides a vacuum vessel, an exhaust means for reducing the pressure in the vacuum vessel and maintaining the pressure, and plasma generation for generating plasma provided in the vacuum vessel. And a substrate holding mechanism for holding the substrate, the substrate holding mechanism being arranged so that the processing surface of the substrate faces a plasma generation space where plasma is generated by the plasma generation unit And a peripheral wall that surrounds the plasma generation space and the base material holding mechanism, and a plurality of gas blown in a direction oblique to the wall surface of the peripheral wall toward the space surrounded by the peripheral wall. Provided is a surface treatment apparatus for treating a surface of a base material in which a first gas supply port is formed.

  Moreover, according to the preferable form of this invention, the surface treatment apparatus containing the gas supply port which blows off gas toward the said plasma production space among the said 1st gas supply ports is provided.

  Further, according to a preferred embodiment of the present invention, the direction in which the gas supplied from the first gas supply port is blown out from the direction perpendicular to the direction from the plasma generation space toward the substrate holding mechanism is higher. Provided is a surface treatment apparatus that is inclined toward a holding mechanism.

  Further, according to a preferred embodiment of the present invention, the first gas supply port has a hole shape, the arbitrary first gas supply port is a gas supply port A, and the gas supplied from the gas supply port A A gas supply that is another first gas supply port adjacent to the gas supply port A in a direction in which the gas discharge direction is projected onto the surface of the peripheral wall as viewed from the space surrounded by the peripheral wall. Λ is the mean free path in the space surrounded by the peripheral wall of the gas supplied from the gas supply port A, and the blowing direction of the gas supplied from the gas supply port A. Provided is a surface treatment apparatus in which the interval between the peripheral edge of the gas supply port A and the peripheral edge of the gas supply port B is λ · cos θ or less, where θ is the angle (acute angle) made with the surface of the peripheral wall. To do.

  Further, according to a preferred embodiment of the present invention, the first gas supply port is slit-shaped, the arbitrary first gas supply port is a gas supply port A, and the gas supplied from the gas supply port A A gas supply that is another first gas supply port adjacent to the gas supply port A in a direction in which the gas discharge direction is projected onto the surface of the peripheral wall as viewed from the space surrounded by the peripheral wall. Λ is the mean free path in the space surrounded by the peripheral wall of the gas supplied from the gas supply port A, and the blowing direction of the gas supplied from the gas supply port A. An angle (acute angle) made with the surface of the peripheral wall is θ, and a direction in which the blowing direction of the gas supplied from the gas supply port A is projected onto the surface of the peripheral wall as viewed from the space surrounded by the peripheral wall is a direction C. When the peripheral portion of the gas supply port A and the Provided is a surface treatment apparatus in which a distance in the direction C of a peripheral edge portion of a gas supply port B is λ · cos θ or less.

  Further, according to a preferred embodiment of the present invention, the plasma generating means is composed of an anode and a cathode arranged with a space with respect to the anode, and through the space between the anode and the cathode, Provided is a surface treatment apparatus including a second gas supply port arranged to blow gas toward a substrate holding mechanism.

  Further, according to a preferred embodiment of the present invention, the base material holding mechanism is disposed away from the plasma generation space, and the base material holding mechanism and the plasma generation space among the first gas supply ports are provided. Provided is a surface treatment apparatus including a gas supply port that blows out gas toward a space between the two.

  Further, according to a preferred embodiment of the present invention, the surface treatment includes the third gas supply port that blows gas into the space between the plasma generation space and the base material holding mechanism without passing through the plasma generation space. Providing equipment.

  In order to solve the above-mentioned problems, the present invention reduces the pressure inside the vacuum vessel and supplies either or both of a polymerizable and non-polymerizable gas from the first gas supply port toward the plasma generation space. Provided is a surface treatment method for supplying and generating plasma in the plasma generation space to treat the surface of the substrate held by the substrate holding mechanism.

  According to a preferred embodiment of the present invention, the inside of the vacuum vessel is depressurized and non-polymerizable gas is supplied from the first gas supply port toward the space between the plasma generation space and the substrate holding mechanism. Then, either a polymerizable or non-polymerizable gas or both are supplied from the second gas supply port through the plasma generation space between the anode and the cathode toward the substrate holding mechanism. However, the present invention provides a surface treatment method in which plasma is generated in the plasma generation space to treat the surface of the substrate held by the substrate holding mechanism.

  According to a preferred embodiment of the present invention, the vacuum vessel is depressurized, non-polymerizable gas is supplied from the first gas supply port to a space surrounded by the peripheral wall, and the second gas supply port Through the plasma generation space between the anode and the cathode to supply the non-polymerizable gas toward the substrate holding mechanism, and without passing through the plasma generation space from the third gas supply port, the plasma A surface treatment method for supplying a polymerizable gas to a space between a generation space and the base material holding mechanism, generating plasma in the plasma generation space, and processing a surface of the base material held by the base material holding mechanism I will provide a.

The meanings of terms in the present invention are as follows.
“Plasma generation means” refers to a device that ionizes at least a part of a supplied gas into ions or electrons. As an example of the excitation method for ionizing a gas, an excitation method using an inductive coupling type or a capacitive coupling type discharge can be cited as an example, but any other excitation method such as photoexcitation type or thermal excitation type can be used. Good.

  The “peripheral wall” refers to a material composed of an arbitrary material and member so as to surround the base material holding mechanism and the plasma generation space or / and the space between the plasma generation space and the base material holding mechanism. You may use electrode members, such as an anode and a cathode which comprise a plasma production | generation means, as a part of member which comprises a surrounding wall.

  “Surface treatment” includes etching, vapor deposition, sputtering, CVD, and the like. Above all, CVD is the present invention because, in addition to the active species generated by the ionization of the non-polymerizable gas used for plasma excitation, there is adhesion of film-forming species generated by the decomposition of the polymerizable gas. It is suitable as a target of the above.

  “Active species” refers to particles in which the non-polymerizable gas supplied to the plasma generation space is chemically activated by the energy supplied by the energy supply source. Examples of the active species include charged particles such as ions and electrons generated by ionization of a non-polymerizable gas, radicals, and excited species. However, the type of active species is not limited to these.

  “Film-forming species” refers to particles in a state in which the polymerizable gas supplied to the plasma generation space is decomposed by energy applied by an energy supply source or by collision with active species.

  The “gas blowing direction” refers to the direction of the gas flow of the adhesion loss suppressing gas along the central axis of the first gas supply port.

  The “adhesion loss suppressing gas” refers to a gas whose function is to push back active species and film formation species that have flowed into the surface of the peripheral wall into a space surrounded by the peripheral wall.

  “Non-polymerizable gas” refers to a gas that does not form a polymer by combining active species generated by decomposition by plasma with the gas alone.

  “Polymerizable gas” refers to a gas that can form a polymer such as a thin film or fine particles by the bonding of film-forming species generated by being decomposed by plasma alone.

  “Plasma excitation gas” refers to a gas that is ionized by energy supplied by an energy supply source connected to plasma generation means and at least partially generates electrons and ions.

  According to the surface treatment apparatus and the surface treatment method of the present invention, as described below, the amount of active species and film-forming species generated by plasma adheres to the peripheral wall surface and is lost is reduced to the substrate surface. Since the amount supplied can be increased, the surface treatment can be performed at high speed.

It is the schematic sectional drawing which showed an example of the surface treatment apparatus of this invention. It is the figure which showed about the blowing direction of the gas supplied from the 1st gas supply port in this invention, and the coating area of the surrounding wall surface. It is the figure which showed the positional relationship of adjacent 1st gas supply ports in this invention. It is the figure which showed the main components of another aspect of the surface treatment apparatus in this invention. It is the figure which showed the main components of another aspect of the surface treatment apparatus in this invention. It is the figure which showed the main components of another aspect of the surface treatment apparatus in this invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
Please refer to FIG. FIG. 1 is a schematic sectional view showing an example of the surface treatment apparatus of the present invention. The surface treatment apparatus of the present invention includes a vacuum vessel 1, and a substrate holding mechanism 4 for holding the substrate 3, a plasma generation means 5, and a peripheral wall 10 inside the vacuum vessel 1. The vacuum vessel 1 is connected to an exhaust means 2 for reducing the pressure inside the vacuum vessel 1 and maintaining the reduced pressure state. An energy supply source 9 is connected to the plasma generating means 5. The substrate holding mechanism 4 and the plasma generating means 5 are arranged so that the surface to be processed of the substrate 3 held by the substrate holding mechanism 4 faces the plasma generation space 6 where plasma is generated by the plasma generating means 5. Has been. The peripheral wall 10 surrounds the plasma generation space 6 and the substrate holding mechanism 4. A plurality of first gas supply ports 12 are formed in the peripheral wall 10 to blow out adhesion loss suppressing gas in an oblique direction with respect to the wall surface of the peripheral wall 10 toward a space 11 a surrounded by the peripheral wall 10. An adhesion loss suppression gas supply path 7a is connected to the peripheral wall 10, and an adjustment mechanism 8a for adjusting the flow rate of the adhesion loss suppression gas blown out to the space 11a is connected to the supply path 7a.

  As a kind of the adhesion loss suppressing gas blown out from the first gas supply port 12, either a non-polymerizable gas or a polymerizable gas may be used. Examples of the polymerizable gas include TEOS (tetraethoxysilane), TMS (tetramethoxysilane), HMDS (hexamethyldisilazane), HMDSO (hexamethyldisiloxane), methane, ethane, ethylene, acetylene, and the like. Examples of non-polymerizable gases include argon, oxygen, nitrogen, hydrogen, helium and the like. The kind of polymerizable gas and non-polymerizable gas is not limited to these.

  The adhesion loss suppression gas blown out from the first gas supply port 12 toward the plasma generation space 6 by the energy supply source 9 connected to the plasma generation means 5 is used as the plasma excitation gas, and the adhesion loss suppression gas blown out. Energy is applied to ionize the adhesion loss suppression gas to generate plasma. When the adhesion loss suppressing gas is a non-polymerizable gas, active species are generated by ionization. When the adhesion loss suppressing gas is a polymerizable gas, a film-forming species is generated by ionization. The activated species and film-forming species in the generated plasma are supplied to the surface to be treated of the substrate 3 to perform surface treatment.

  In this embodiment, the effect by blowing out the adhesion loss suppressing gas from the first gas supply port 12 is that the non-polymerized gas is used as the adhesion loss suppressing gas, and the active species are generated by ionization, and the adhesion loss suppressing gas is Since it is the same as the case where a film forming species is generated by ionization using a polymerizable gas, unless otherwise specified, a non-polymerized gas is used as an adhesion loss suppressing gas and active species are generated by ionization in the following description. The embodiment described above will be described as an example.

  Examples of the gas excitation method in the plasma generating means 5 include an excitation method using an inductive coupling type or capacitive coupling type discharge, but any other excitation method such as an optical excitation type or a thermal excitation type may be used. Moreover, the energy supply source 9 can select suitably what can supply energy, such as electricity, heat, and light, according to the excitation method. When electricity is supplied as energy for plasma excitation, the power source may be a DC power source or an AC power source.

  In the surface treatment apparatus of FIG. 1, the plasma generation unit 5 is provided separately from the peripheral wall 10, but the peripheral wall 10 may also have a function of serving as the plasma generation unit 5.

  With the configuration as shown in FIG. 1, the active species generated by the ionization of the adhesion loss suppression gas are pushed back into the space 11 a by the adhesion loss suppression gas blown from the first gas supply port 12, and the peripheral wall 10 The amount of active species attached to the surface and lost can be reduced.

  Please refer to FIG. As shown in FIG. 2, the first gas supply port 12 is formed so that the gas blowing direction 13 is oblique to the wall surface of the peripheral wall 10. Since the gas blowing direction 13 is inclined as described above, the area covering the surface of the peripheral wall 10 is smaller than that of the case where the adhesion loss suppressing gas is blown vertically from the surface of the peripheral wall 10 toward the space 11a. The blowing direction 13 is increased by the covering area 15 projected onto the surface of the peripheral wall 10. Thereby, the probability that the active species flowing into the surface of the peripheral wall 10 existing in the space 11a are pushed back to the space 11a is improved, and the amount of active species attached to the surface of the peripheral wall 10 and lost can be further reduced. As a result, the amount of active species supplied to the treated surface of the substrate 3 increases, and the treatment speed of the surface treatment can be improved.

  When a polymerizable gas is supplied as an adhesion loss suppressing gas from the first gas supply port 12, the amount of film formation species supplied to the processing surface of the base material 3 is increased and formed on the processing surface of the base material 3. The film forming rate of the thin film can be improved. Furthermore, since the amount of film forming species adhering to the surface of the peripheral wall 10 is reduced, it is difficult to form a thin film on the surface of the peripheral wall 10, the frequency of cleaning the apparatus is reduced, and the discharge is stably performed over a long period of time. Can be reduced.

  Refer to FIG. 1 again. Further, as shown in FIG. 1, by enclosing the space 11 a with the peripheral wall 10, diffusion of active species generated by plasma can be prevented, and active species can be efficiently supplied to the treated surface of the substrate 3.

  The flow rate of the adhesion loss suppression gas blown out from the first gas supply port 12 is to supply the same number of particles as the number of particles flowing into the surface of the peripheral wall 10 determined by the pressure in the space 11a or a number exceeding the number of particles. It is preferable to set a flow rate that can be achieved. By setting the flow rate of the adhesion loss suppressing gas blown from the first gas supply port 12 to such a flow rate, an amount necessary for pushing back all particles flowing into the surface of the peripheral wall 10 in the space 11a back into the space 11a. Thus, a higher active species adhesion loss suppression effect can be obtained.

  Furthermore, it is more preferable that the flow rate of the adhesion loss suppressing gas blown from the first gas supply port 12 is set to a flow rate that can supply the number of particles equal to the number of particles flowing into the surface of the peripheral wall 10. By setting the flow rate of the adhesion loss suppressing gas blown out from the first gas supply port 12 to such a flow rate, all the particles flowing into the surface of the peripheral wall 10 in the space 11a are pushed back into the space 11a and the exhaust means The increase in capacity of 2 can be suppressed. Thereby, the increase in the supply amount of the active species with respect to the process surface of the base material 3 and the suppression of an increase in equipment cost can be made compatible.

  The first gas supply port 12 is formed so that the gas blowing direction is inclined to the substrate holding mechanism 4 side from the direction 14b orthogonal to the direction 14a from the plasma generation space 6 toward the substrate holding mechanism 4. Is preferred. By adopting such a configuration, in addition to the effect of increasing the coating area 15 on the surface of the peripheral wall 10, the activated species that the gas particles of the adhesion loss suppression gas push back are directed toward the substrate holding mechanism 4, and the space The flight distance until the active species pushed back to 11a reaches the surface of the substrate 3 is shortened. As a result, the probability that the active species recombine and disappear in the space 11a is reduced, and the amount of active species supplied to the treatment surface of the substrate 3 can be increased. Thereby, the processing speed of the surface treatment can be improved.

    Please refer to FIG. When the shape of the first gas supply port 12 is a hole, as shown in FIG. 3, the blowing direction 13 of the gas supplied from the first gas supply port 12 (refer to FIG. 2 for the direction 13). In the direction 16 projected on the surface of the peripheral wall 10 when the gas blowing direction 13 is viewed from the space surrounded by the peripheral wall 10 (hereinafter referred to as the covering direction 16), another adjacent first gas supply port 12 is used. It is preferable to be in the direction in which. If the mean free path determined by the pressure in the space 11a and the type of gas existing in the space 11a is λ, and the angle 18 formed by the gas blowing direction 13 and the surface of the peripheral wall 10 is θ, the peripheral wall 10 is moved by the adhesion loss suppressing gas. The covering area 15 to be covered is represented by λ · cos θ. In order to efficiently push back the active species with the adhesion loss suppression gas, it is preferable that the coating areas 15 of the adhesion loss suppression gas supplied from the plurality of first gas supply ports 12 do not overlap each other. However, if the gas blowing directions 13 from the plurality of first gas supply ports 12 are set in arbitrary directions, there is a concern that the covering areas 15 overlap. Therefore, as described above, the blowing direction 13 of the gas supplied from the first gas supply port 12 is determined so that another adjacent first gas supply port 12 exists in the covering direction 16. Thus, it is possible to prevent the covering areas 15 from overlapping as much as possible.

  Furthermore, an arbitrary first gas supply port 12 is a gas supply port A, and the adjacent first gas supply port 12 in the coating direction 16 of the gas blowing direction 13 supplied from the gas supply port A is a gas supply port. When B is set, the distance 17 between the peripheral portions of the gas supply port A and the gas supply port B is preferably set to be λ · cos θ or less. By setting the interval 17 to be equal to or less than λ · cos θ, the surface of the peripheral wall 10 between the peripheral portions of the first gas supply ports 12 adjacent in the coating direction 16 of the adhesion loss suppressing gas can be covered with the coating area 15, There is no gap in which the active species reaches the surface of the peripheral wall 10 between the peripheral portions. The distance 17 between the peripheral portions of the gas supply port A and the gas supply port B is more preferably λ · cos θ. By setting the interval 17 to λ · cos θ, there is no useless portion where the covering areas 15 overlap each other, and the attachment loss of active species can be efficiently suppressed without wasting the attachment loss suppression gas.

  Please refer to FIG. In the embodiment of FIG. 4, the first gas supply port 12 formed in the peripheral wall 10 has a slit shape. Thus, by making the shape of the 1st gas supply port 12 into a slit shape, the adhesion loss suppression gas can be blown out without a gap in the slit long side 19 direction. As a result, the area covering the surface of the peripheral wall 10 with the adhesion loss suppressing gas increases, and the active species that have flowed toward the surface of the peripheral wall 10 are blown out from the first gas supply port 12 into the space 11a. The probability of pushing back is improved, and the amount of active species attached to the surface of the peripheral wall 10 and lost can be reduced. As a result, more active species can be supplied to the treated surface of the substrate 3. Further, when the direction of the long side 19 of the slit shape is a direction parallel to the surface of the base material 3, when the area of the base material 3 is increased, the gas is uniformly uniform with respect to the slit long side 19 direction of the base material 3. Thus, the substrate 3 having a large area can be uniformly surface-treated.

  Furthermore, when the shape of the first gas supply port 12 is a hole, a large number of first gas supply ports 12 must be formed in the direction of the slit long side 19 when the base material 3 is enlarged. By making the shape of the first gas supply port 12 into a slit shape, the processing of the first gas supply port 12 can be saved. Thereby, shortening of a production period and increase in processing cost can be suppressed.

  When the slit-shaped first gas supply port 12 is a gas supply port A and the slit-shaped first gas supply port 12 adjacent to the gas supply port A is a gas supply port B, the gas supply port The distance 17 between the peripheral portions of A and the gas supply port B is preferably λ · cos θ or less, and more preferably λ · cos θ. The reason for this is the same as in the case where the first gas supply port 12 has a hole shape, and by setting the interval 17 to λ · cos θ or less, the peripheral portions of the adjacent first gas supply ports 12 are adjacent to each other. The surface of the peripheral wall 10 can be completely covered with the covering area 15, and there is no gap for the active species to reach the surface of the peripheral wall 10. By setting the interval 17 to λ · cos θ, there is no useless portion where the coating areas 15 overlap each other, and the attachment loss of active species can be efficiently suppressed without wasting the attachment loss suppression gas.

  Please refer to FIG. FIG. 5 is a diagram showing the main components of another aspect of the surface treatment apparatus of the present invention. The surface treatment apparatus shown in FIG. 5 includes a second gas supply port 20, and the plasma generation means 5 includes an anode 21 and a cathode 22 that is opposed to the anode 21 by providing a space. The substrate holding mechanism 4 is disposed at a position spaced from the plasma generation space 6, and the second gas supply port 20 is configured such that the gas blown out from the second gas supply port 20 is between the anode 21 and the cathode 22. It is disposed at a position that passes through the plasma generation space 6 and hits the processing surface of the substrate 3 held by the substrate holding mechanism 4. The first gas supply port 12 is provided with the adhesion loss suppression gas on the wall surface of the peripheral wall 10 toward the plasma generation space 6 and the space 11b between the plasma generation space 6 and the substrate holding mechanism 4 surrounded by the peripheral wall 10. On the other hand, it is arranged to blow in an oblique direction. The second gas supply port 20 is connected to a supply path 7b and an adjustment mechanism 8b for adjusting the gas supply amount.

  In this embodiment, the effect of blowing out the adhesion loss suppressing gas from the first gas supply port 12 is that non-polymerized gas is supplied from the second gas supply port 20 and activated species are generated by ionization in the plasma generation space 6. And the case where the polymerizable gas is supplied from the second gas supply port 20 and the film-forming species is generated by ionization in the plasma generation space 6, are not particularly described in the following description. Unless otherwise specified, an embodiment in which the non-polymerizable gas is supplied from the second gas supply port 20 will be described as an example.

  The second gas supply port 20 is preferably electrically insulated from the cathode 22. Since the second gas supply port 20 is electrically insulated, a high cathode 22 voltage is not applied to the second gas supply port 20, and the occurrence of abnormal discharge that causes discharge outside the plasma generation space 6 is suppressed. it can. By suppressing this abnormal discharge, power can be stably supplied to the cathode 22 and the discharge in the plasma generation space 6 can be stabilized. Further, when the polymerizable gas is blown out from the second gas supply port 20, it is possible to suppress discharge in the vicinity of the second gas supply port 20, thereby preventing the formation of a thin film at the second gas supply port 20. As a result, blockage of the second gas supply port 20 can be suppressed, and long-term stable gas supply and thin film formation on the processing surface of the substrate 3 can be performed.

  Thus, the base material 3 is separated from the plasma generated in the plasma generation space 6 by disposing the base material holding mechanism 4 with the space 11 b being spaced from the plasma generation space 6. As a result, plasma damage and thermal load on the substrate 3 can be reduced. Further, the gas blown out from the second gas supply port 20 through the second gas supply port 20 passes through the plasma generation space 6 and hits the processing surface of the substrate 3 held by the substrate holding mechanism 4. By arranging, the active species generated by the plasma flow to the processing surface of the substrate 3 along the flow of the gas blown out from the second gas supply port 20. As a result, the generated active species can be efficiently supplied to the treated surface of the substrate 3. Thereby, the processing speed of surface treatment improves.

  The length h1 of the gas flow direction 23 blown out from the second gas supply port 20 of the anode 21 constituting the plasma generating means 5 and the length h2 of the gas flow direction 23 blown out from the second gas supply port 20 of the cathode 22 are These are preferably longer than the distance w between the anode 21 and the cathode 22. The length h1 and the length h2 were made longer than the distance w between the anode 21 and the cathode 22, and the plasma generation space 6 was expanded in the direction of the length h1 and the length h2, thereby blowing out from the second gas supply port 20. The time for the gas to pass through the plasma generation space 6 becomes longer. As a result, decomposition of the gas blown out from the second gas supply port 20 is promoted, and the amount of generated active species increases. As a result, the amount of active species supplied to the treated surface of the substrate 3 increases, so that the treatment speed of the surface treatment is improved.

  The length h1 of the gas flow direction 23 of the gas blown from the second gas supply port 20 of the anode 21 and the length h2 of the gas flow direction 23 of the gas blown from the second gas supply port 20 of the cathode 22 are not necessarily the same length. However, the lengths are preferably the same. As shown in FIG. 5, when the lengths h1 and h2 are the same, an electric field is uniformly formed between the anode 21 and the cathode 22, so that it is formed in the gas flow direction 23 blown out from the second gas supply port 20. The plasma bias can be reduced. Thereby, the density distribution of the active species generated between the anode 21 and the cathode 22 can be made uniform, and the bias of the supply amount of the active species to the substrate 3 treatment surface held in the substrate holding mechanism 4 can be suppressed. it can. As a result, it is possible to perform a surface treatment that suppresses unevenness.

  Although the anode 21 and the cathode 22 do not necessarily have to be parallel, it is more preferable that they are arranged substantially in parallel. By arranging the anode 21 and the cathode 22 substantially in parallel, uniform electrolysis can be formed between the anode 21 and the cathode 22. Thereby, generation | occurrence | production of abnormal discharge by local electrolytic concentration can be suppressed, and electric power can be stably supplied to the cathode 22. Here, “substantially parallel” means that the anode 21 and the cathode 22 are designed to be parallel, and even if they are slightly deviated from parallel due to manufacturing errors, they are assumed to be included substantially in parallel. On the other hand, if the anode 21 and the cathode 22 are designed not to be parallel, they are not included in substantially parallel.

  In the surface treatment apparatus of FIG. 5, the first gas supply port 12 is directed to the plasma generation space 6 surrounded by the peripheral wall 10 and the space 11 b between the plasma generation space 6 and the substrate holding mechanism 4. The adhesion loss suppressing gas is blown out from the gas supply port 12. In the plasma generation space 6, a diffusion flow of active species is generated from a region having a high plasma density existing in the plasma generation space 6 toward a region having a low plasma density around the plasma generation space 6 in accordance with the gradient of the plasma density. The active species flow toward the surface of the peripheral wall 10 surrounding the plasma generation space 6 by this diffusion flow. Therefore, in the plasma generation space 6, in addition to the loss due to the attachment of the active species flying freely in the space 11b to the peripheral wall 10, an attachment loss due to the diffusion flow occurs. Further, the adhesion loss due to the diffusion flow is larger than the adhesion loss generated on the surface of the peripheral wall 10 surrounding the space 11b. Therefore, the adhesion loss suppression gas is blown out from the first gas supply port 12 toward the plasma generation space 6 to reduce the adhesion loss due to this diffusion flow, and the active species collides with the peripheral wall 10 surrounding the plasma generation space 6. The amount of adhering can be greatly reduced. Thereby, deterioration and contamination of the peripheral wall 10 due to collision of active species and adhesion can be prevented, and long-term stable discharge and maintenance frequency can be reduced. In addition, the amount of active species supplied to the treated surface of the substrate 3 is further increased, and the treatment speed of the surface treatment can be greatly improved.

  In the apparatus configuration shown in FIG. 5, it is preferable that the type of gas blown out from the first gas supply port 12 is a non-polymerizable gas, and the gas blown out from the second gas supply port 20 is a polymerizable gas or a non-polymerizable gas. .

  When the kind of gas blown out from the first gas supply port 12 and the second gas supply port 20 is such a combination, from the second gas supply port 20 that flows toward the surface of the peripheral wall 10 in the space 11b. The non-polymerizable gas blown out or the activated species or film-forming species generated by the decomposition of the polymerizable gas is pushed back into the space 11b by the non-polymerizable gas blown out from the first gas supply port 12 as an adhesion loss suppressing gas. Thus, the amount of active species and film-forming species that adhere to the surface of the peripheral wall 10 and are lost can be reduced. Thereby, the supply amount of the active species and the film forming species to the processing surface of the substrate 3 is increased, and the film forming rate of the thin film formed on the processing surface of the substrate 3 can be improved. Furthermore, it is possible to suppress the formation of a thin film due to adhesion of active species or film-forming species to the surface of the peripheral wall 10 surrounding the space 11b, and stable discharge and maintenance over a long period of time by reducing the cleaning frequency of the electrode members. Cost can be reduced.

  Further, when the same type of gas as the non-polymerizable gas blown out from the first gas supply port 12 is blown out from the second gas supply port 20, the ionization of the non-polymerizable gas blown out from the second gas supply port 20 causes The generated active species and the non-polymerizable gas blown out from the first gas supply port 12 collide in the space 11b, and are generated by ionization of the non-polymerizable gas blown out from the second gas supply port 20. Apart from the active species, the non-polymerizable gas blown out from the first gas supply port 12 is ionized to generate active species. As a result, the amount of active species supplied to the treated surface of the substrate 3 can be increased while reducing the amount of active species attached to the peripheral wall 10 and lost. Thereby, the processing speed of surface treatment can be improved.

  Please refer to FIG. It is the figure which showed the main components of another aspect of the surface treatment apparatus of FIG. The configuration shown in FIG. 6 is a configuration that includes a third gas supply port 24 that blows gas into the space 11b without passing through the plasma generation space 6 in contrast to the configuration shown in FIG.

  By configuring as shown in FIG. 6, the distance 25 between the plasma generation space 6 and the processing surface of the substrate 3 is arbitrarily set according to the pressure in the space 11b and the type of gas existing in the space 11b. The number of times the active species generated in the plasma generation space 6 and the polymerizable gas blown out from the third gas supply port 24 collide with each other in the space 11b before being supplied to the processing surface of the substrate 3 can be controlled. By controlling the amount of film-forming species generated in the space 11b according to the number of collisions between the active species and the polymerizable gas, the ratio between the active species and the amount of film-forming species supplied to the processing surface of the substrate 3 is controlled. be able to. As a result, the film quality of the thin film formed on the treated surface of the substrate 3 can be controlled.

  In the apparatus configuration shown in FIG. 6, the gas type blown out from the first gas supply port 12 is a non-polymerizable gas, and the gas type blown out from the second gas supply port 20 is the same type as the gas blown out from the first gas supply port 12. The non-polymerizable gas and the type of gas blown out from the third gas supply port 24 are preferably polymerizable gases. By using such a combination of gases, the amount of active species and film-forming species attached to and lost on the surface of the peripheral wall 10 is reduced, and the gas blown out from the second gas supply port 20 is ionized to generate. In addition to the active species to be generated, the non-polymerizable gas supplied from the first gas supply port 12 in the space 11b is ionized in the plasma generation space 6 by plasma, and the amount of active species supplied to the space 11b is increased. Can do. Thereby, the decomposition of the polymerizable gas blown out from the third gas supply port 24 in the space 11b is promoted, and the amount of film forming species supplied to the processing surface of the substrate 3 increases. As a result, the film forming rate of the thin film formed on the treated surface of the substrate 3 is improved.

  Further, when the polymerizable gas is blown out from the third gas supply port 24, the active species generated by the ionization of the non-polymerizable gas blown out from the second gas supply port 20 and the third gas supply port 24. By colliding with the blown-out polymerizable gas, the polymerizable gas is decomposed in the space 11b and a film-forming species is generated. The generated film formation species are supplied to the processing surface of the base material 3 without passing through the plasma generation space 6 along the flow of gas blown out from the second gas supply port 20. The amount of film forming species present can be reduced. As a result, it is possible to prevent film formation species from adhering to the surfaces of the anode 21 and the cathode 22 constituting the plasma generating means 5 and to form a thin film, thereby reducing the cleaning cycle of the electrode member and stable discharge over a long period of time. It can be carried out.

  In the following examples, the surface treatment effect on the substrate surface was measured.

[Example 1]
The surface of the polyethylene terephthalate film (“Lumirror (registered trademark)” manufactured by Toray Industries, Inc.) having a thickness of 12 μm and a length of 70 mm was dry-etched using the surface treatment apparatus having the configuration shown in FIG. Surface treatment conditions are as follows.

(Vacuum container conditions)
Vacuum vessel pressure: 5Pa
(Electrode configuration conditions)
Discharge method: capacitively coupled parallel plate electrode anode, cathode distance: 30 mm
Anode, cathode height: 200mm
Anode, cathode depth length: 200m
Distance between peripheral walls: 70mm
Distance between plasma generation space and substrate surface: 50mm
Shape of the first gas supply port: slit having a width of 1 mm × length in the depth direction of 180 mm Arrangement of the first gas supply port: 4 on each peripheral wall surface, 6 mm between the peripheral portions
Adhesion loss suppression gas supply angle: 45 ° (base material holding mechanism side)
(Surface treatment conditions)
Adhesion loss suppression gas type supplied from the first gas supply port: Oxygen adhesion loss suppression gas Total flow rate: 0, 400 sccm
Plasma excitation gas type supplied from the second gas supply port: Oxygen plasma excitation gas flow rate: 1000 sccm
Processing time: 1 minute Power supply: RF power supply (frequency: 13.56 MHz)
Electric power: 300W.

The etching rate of the base material subjected to the surface treatment under the above conditions was measured by the following method (measuring method)
Measuring instrument: Step measuring instrument
(Surfcorder ET4000A manufactured by Kosaka Laboratory Ltd.)
Measurement content: A base material having a length of 70 mm was measured 15 times at intervals of 5 mm, 3 times for each location, and the average value of the etching rate in the length direction was calculated.

  Under the above conditions, the substrate surface was dry etched to evaluate the etching rate of the substrate surface. The etching rate was 85.0 nm / min.

[Example 2]
Dry etching was performed under the same conditions as in Example 1 except that the supply direction of the adhesion loss suppressing gas in the electrode configuration conditions was changed to the plasma excitation gas supply port side. The etching rate was 71.1 nm / min.

[Example 3]
Dry etching was performed under the same conditions as in Example 1 except that the type of the adhesion loss suppression gas in the surface treatment conditions was changed to argon. The etching rate was 75.7 nm / min.

[Comparative Example 1]
Dry etching was performed under the same conditions as in Example 1 except that the adhesion loss suppressing gas under the surface treatment conditions was not supplied. The etching rate was 59.8 nm / min, which was lower than those in Examples 1, 2, and 3.

  The present invention can be applied not only to a plasma CVD apparatus but also to a surface treatment such as a surface modification apparatus or an etching apparatus, but the application range is not limited thereto.

DESCRIPTION OF SYMBOLS 1 Vacuum container 2 Exhaust means 3 Base material 4 Base material holding mechanism 5 Plasma generation means 6 Plasma generation space 7 Gas supply path 8 Gas flow rate adjustment mechanism 9 Energy supply source 10 Peripheral wall 11 Space surrounded by peripheral wall 12 First gas supply Port 13 Adhesion loss suppression gas blowing direction 14a Direction from plasma generation space toward substrate holding mechanism 14b Direction orthogonal to direction from plasma generation space toward substrate holding mechanism 15 Covering area 16 Covering direction 17 First gas supply Interval between the peripheral edges of the mouth 18 Angle θ formed between the gas blowing direction and the surface of the peripheral wall
19 Slit Long Side 20 Second Gas Supply Port 21 Anode 22 Cathode 23 Gas Flow Direction 24 Third Gas Supply Port 25 Distance between Plasma Generation Space and Substrate Processing Surface

Claims (11)

A vacuum vessel;
An evacuation means for reducing the pressure inside the vacuum vessel and maintaining the pressure;
Plasma generating means provided in the vacuum vessel for generating plasma;
A substrate holding mechanism for holding the substrate, the substrate holding mechanism disposed so that a processing surface of the substrate faces a plasma generation space in which plasma is generated by the plasma generation unit;
A peripheral wall surrounding the plasma generation space and the substrate holding mechanism,
Surface treatment for treating the surface of the base material, in which a plurality of first gas supply ports for blowing gas obliquely to the wall surface of the peripheral wall are formed in the peripheral wall toward the space surrounded by the peripheral wall apparatus.   The surface treatment apparatus of Claim 1 including the gas supply port which blows off gas toward the said plasma production space among said 1st gas supply ports.   The blowing direction of the gas supplied from the first gas supply port is inclined to the substrate holding mechanism side rather than the direction orthogonal to the direction from the plasma generation space toward the substrate holding mechanism side. Or the surface treatment apparatus of 2. The first gas supply port has a hole shape;
Arbitrary first gas supply port is a gas supply port A, and the blowing direction of the gas supplied from the gas supply port A is the surface of the peripheral wall when the blowing direction of the gas is viewed from the space surrounded by the peripheral wall. Is a direction in which a gas supply port B which is another first gas supply port adjacent to the gas supply port A exists in the direction projected onto
Λ is the mean free path of the gas supplied from the gas supply port A in the space surrounded by the peripheral wall, and the angle between the blowing direction of the gas supplied from the gas supply port A and the surface of the peripheral wall ( The surface treatment apparatus according to claim 1, wherein an interval between the peripheral edge of the gas supply port A and the peripheral edge of the gas supply port B is equal to or less than λ · cos θ, where θ is an acute angle. The first gas supply port has a slit shape;
Arbitrary first gas supply port is a gas supply port A, and the blowing direction of the gas supplied from the gas supply port A is the surface of the peripheral wall when the blowing direction of the gas is viewed from the space surrounded by the peripheral wall. Is a direction in which a gas supply port B which is another first gas supply port adjacent to the gas supply port A exists in the direction projected onto
Λ is the mean free path of the gas supplied from the gas supply port A in the space surrounded by the peripheral wall, and the angle between the blowing direction of the gas supplied from the gas supply port A and the surface of the peripheral wall ( Θ is an acute angle), and the direction in which the direction of the gas supplied from the gas supply port A is projected onto the surface of the peripheral wall when viewed from the space surrounded by the peripheral wall is the direction C. The surface treatment apparatus according to claim 1, wherein the distance in the direction C between the peripheral edge and the peripheral edge of the gas supply port B is equal to or less than λ · cos θ. The substrate holding mechanism is disposed away from the plasma generation space;
The surface treatment apparatus according to claim 1, further comprising a gas supply port that blows gas toward a space between the base material holding mechanism and the plasma generation space among the first gas supply ports. The plasma generating means includes an anode and a cathode disposed with a space with respect to the anode,
The surface treatment apparatus according to claim 1, further comprising a second gas supply port arranged to blow gas toward the substrate holding mechanism through a space between the anode and the cathode. .   The surface treatment apparatus of Claim 6 or 7 provided with the 3rd gas supply port which blows off gas to the space between the said plasma production space and the said base material holding | maintenance mechanism without passing through the said plasma production space. Using the surface treatment apparatus according to claim 1,
Depressurizing the inside of the vacuum vessel,
Supplying one or both of a polymerizable gas and a non-polymerizable gas from the first gas supply port toward the plasma generation space;
A surface treatment method for producing a plasma in the plasma generation space and treating a surface of a substrate held by the substrate holding mechanism. Using the surface treatment apparatus of claim 7,
Depressurizing the inside of the vacuum vessel,
Supplying a non-polymerizable gas from the first gas supply port toward the space between the plasma generation space and the substrate holding mechanism;
While supplying one or both of polymerizable and non-polymerizable gases from the second gas supply port through the plasma generation space between the anode and the cathode toward the substrate holding mechanism,
A surface treatment method for producing a plasma in the plasma generation space and treating a surface of a substrate held by the substrate holding mechanism. Using the surface treatment apparatus of claim 8,
Depressurizing the inside of the vacuum vessel,
Supplying a non-polymerizable gas from the first gas supply port to the space surrounded by the peripheral wall;
A non-polymerizable gas is supplied from the second gas supply port through the plasma generation space between the anode and the cathode toward the substrate holding mechanism;
Without passing the plasma generation space from the third gas supply port, supplying a polymerizable gas to the space between the plasma generation space and the substrate holding mechanism,
A surface treatment method for producing a plasma in the plasma generation space and treating a surface of a substrate held by the substrate holding mechanism.