JP4567979B2 - Plasma processing system and plasma processing method - Google Patents

Description

The present invention relates to a plasma processing system and a plasma processing method for performing processing using plasma .

  Gas activation by plasma has various applications in various industrial fields. For example, in the manufacture of various electronic devices, various display devices, etc., various surface treatments are performed on a substrate using a gas activated in plasma. These include plasma CVD (Chemical Vapor Deposition) in which a thin film is formed by using a gas phase reaction in plasma, plasma etching in which etching is performed by using the action of active species and ions generated in plasma.

  As one type of plasma used for such gas activation, inductively coupled plasma is known. Inductively coupled plasma is a type of plasma generated using high frequency power, and the plasma and the high frequency electrode are inductively coupled. The inductively coupled plasma method is suitable for a gas activation device because it can generate high-density plasma by an induced current flowing in the plasma and can activate a gas with high efficiency.

  FIG. 9 is a schematic front sectional view of a conventional gas activation apparatus employing an inductively coupled plasma method. The apparatus shown in FIG. 9 is used for the surface treatment as described above, and is mounted on the surface treatment system. The apparatus includes a discharge tube 1 in which plasma is generated by gas discharge therein, a gas supply system 2 that supplies gas to the discharge tube 1, and a high-frequency power application mechanism that applies high-frequency power to the gas in the discharge tube 1. Consists mainly of. The high frequency power application mechanism includes an antenna 31 provided around the discharge tube 1, a high frequency power source 32 that supplies a high frequency current to the antenna 31 to induce a high frequency magnetic field in the discharge tube 1, a high frequency power source 32, and an antenna 31. It is mainly comprised from the matching device 33 provided on the circuit between.

In the discharge tube 1, non-plasmaized gas (neutral gas molecules) is supplied one after another, and electrons in the plasma accelerated by a high-frequency electric field induced by a high-frequency magnetic field are supplied to the neutral gas molecules. collide. The collision causes dissociation, excitation, and the like of the gas molecule, and a chemically active species different from the ground state gas molecule is generated. “Gas activation” refers to the generation of active species in this way. The lower end opening of the discharge tube 1 is connected to the processing chamber 5. A substrate 10 that performs surface treatment is disposed in the processing chamber 5. Active species generated by dissociation, excitation, etc. enter the processing chamber 5 and reach the substrate 10 to be used for surface treatment. The term “dissociation” in the present invention has a broad meaning and includes both ionization and decomposition. That is, even a phenomenon of ionization alone can be referred to as “dissociation”, and a phenomenon of being decomposed into electrically neutral molecules or atoms can also be referred to as “dissociation”.
Japanese Patent No. 3426382 JP 2000-133498 A

  In order to increase the gas activation efficiency, it is necessary to increase the electron density, that is, to increase the plasma density. Generally, the higher the pressure, the more easily the high-density plasma. However, when the pressure is increased, the plasma is likely to be localized, and in the inductively coupled plasma source, the plasma is at a lower concentration in the central portion than in the peripheral portion in the discharge tube. For this reason, in the gas activation apparatus as described above, there is a problem that the density of active species does not increase much even if the pressure is increased due to the relationship with the gas flow in the discharge tube 1. This point will be described with reference to FIG. FIG. 10 is a diagram showing the relationship between the gas pressure and the plasma density in the conventional gas activation apparatus as shown in FIG.

As is well known, the flow velocity of the gas flowing in the discharge tube 1 is large in the central portion of the discharge tube 1 and small in the peripheral portion (FIG. 10 (1)). Therefore, the amount of gas molecules flowing through the central portion is large, and the amount of gas molecules flowing through the peripheral portion is small. This tendency is remarkable when the gas flow is laminar as shown in FIG.
On the other hand, as shown in FIGS. 10 (3) and 10 (4), when plasma is generated in the discharge tube 1 by inductive coupling, the plasma density distribution in a plane perpendicular to the tube axis varies depending on the pressure. When the pressure is high, the plasma sheath is narrow and a high induced current flows in the peripheral portion, so that the plasma density in the peripheral portion becomes high as shown in FIG. That is, the activation efficiency is high in the peripheral portion and low in the central portion. On the other hand, when the pressure is lowered, the mean free path becomes longer and the plasma sheath becomes wider. For this reason, the electrons can move to the vicinity of the center of the discharge tube 1, and therefore the plasma density becomes high at the center where many neutral gas molecules are supplied as shown in FIG. 10 (4). In the present specification, the “tube axis” means a line along the length direction passing through the center of the tube in a plane perpendicular to the length direction of the tube (the direction in which the tube extends).

As can be seen from the above description, in the conventional gas activation device, even if the pressure in the discharge tube 1 is increased, many gas molecules pass through the central portion where the plasma density is relatively low. There is a problem that the activation efficiency is not high. On the other hand, since many gas molecules pass through the central part where the activation efficiency is low, the active species to be obtained cannot be obtained sufficiently, and only the amount of gas consumption increases.
Such a reversal phenomenon of the plasma density distribution depends on the inner diameter of the discharge tube 1, but is about 100 Pa in a practically used dimension (for example, a diameter of 7 cm) in a practically used gas activation device. It is thought that it occurs at the boundary.

The invention of the present application has been made to solve the above-described problems, and provides a technique capable of effectively increasing the gas activation efficiency in a plasma processing system that generates and uses plasma by an inductive coupling method. To do.

In order to solve the above problems, the invention according to claim 1 of the present application includes a discharge tube, a processing chamber communicating with the discharge tube through an opening, a gas supply system for supplying a gas into the discharge tube, and the discharge. A high-frequency power application mechanism that generates inductively coupled plasma by applying high-frequency power to the gas in the tube, a flow restrictor provided in the discharge tube so that the gas flow rate in the peripheral portion is larger than that in the central portion, and the flow rate An end plate attached to one end of the adjustment tool,
The end plate has a floating potential,
A gap is formed between the end plate and the discharge tube so that the gas flows toward the processing chamber.
In order to solve the above-mentioned problem, the invention according to claim 2 is the configuration according to claim 1, wherein the flow restrictor has a shape extending along the axis of the discharge tube and is provided coaxially with the discharge tube. It has the composition of being.
In order to solve the above-mentioned problem, the invention according to claim 3 is the configuration according to claim 1, wherein a magnet for setting a magnetic field is provided between a tube wall of the discharge tube and the flow restrictor. This magnet suppresses the movement of electrons toward each wall surface by setting magnetic field lines in a direction intersecting the flight path of electrons to the wall surface of the discharge tube and the wall surface of the flow restrictor when no magnetic field is provided. It has the structure of.
In order to solve the above problem, the invention according to claim 4 is a plasma processing method using the plasma processing system according to any one of claims 1 to 3 , wherein the conductance is adjusted by the end plate, In this configuration, the process is performed while the pressure in the discharge tube is set higher than the pressure in the process chamber.

As described below, according to the invention described in claim 1 of the present application, since a large amount of gas flows in the periphery of the discharge tube in which a high induced current easily flows, the density of active species generated in the plasma is effectively increased. It is possible to increase the overall activation efficiency effectively. In addition, since the diffusion of electrons is suppressed by the end plate, the plasma in the discharge tube can be made more dense.
Further, according to the second aspect of the invention, in addition to the above effect, the flow restrictor is coaxial with the discharge tube, so the flow path formed by the flow restrictor is also coaxial. For this reason, a uniform gas flow is formed.
This is the optimum configuration when activating the gas while making a difference.
According to the invention described in claim 3 , in addition to the above effects, a higher density plasma can be obtained by the action of the magnet, and gas can be activated more efficiently.

The best mode for carrying out the present invention (hereinafter referred to as an embodiment) will be described below. First, the configuration of a reference example referred to in the description of the configuration of the embodiment will be described.
FIG. 1 is a schematic front sectional view of a plasma processing system according to a first reference example , in which a gas activation device is mounted. As in the apparatus shown in FIG. 9, the gas activation device shown in FIG. 1 includes a discharge tube 1 in which plasma is generated by gas discharge therein, a gas supply system 2 that supplies gas to the discharge tube 1, and a discharge tube 1. It is mainly comprised from the high frequency electric power application mechanism which applies high frequency electric power to the inside gas. The high frequency power application mechanism includes an antenna 31, a high frequency power source 32 that supplies a high frequency current to the antenna 31 to induce a high frequency magnetic field in the discharge tube 1, and a matching provided on a circuit between the high frequency power source 32 and the antenna 31. It is mainly composed of the device 33.

The discharge tube 1 has a cylindrical shape and is provided so as to extend in the vertical direction as shown in FIG. An upper end of the discharge tube 1 is narrowed and a gas supply system 2 is connected thereto. The gas supply system 2 is composed of a cylinder storing the supplied gas, a pipe connecting the cylinder and the discharge tube 1, a valve provided on the pipe, a flow rate regulator, a filter, and the like.
The discharge tube 1 is made of a dielectric material such as quartz glass. The antenna 31 is coiled in this reference example .

  As the high-frequency power source 32, one having an arbitrary frequency in the range of several hundred kHz to several tens of MHz is used. The output is appropriately determined according to the inner diameter of the discharge tube 1, the pressure in the discharge tube 1, and the like. The number of turns of the coiled antenna 31 is about 0.5 to several tens, and the optimum number of turns according to the frequency of the high frequency is experimentally determined. For example, in the case of 13.56 MHz, the number of turns is in the range of 1-5.

A major feature of the gas activation device mounted on the plasma processing system of the reference example is that a flow rate regulator 4 is provided in the discharge tube 1 so that the gas flow rate in the peripheral portion is larger than that in the central portion. Is a point. In this reference example , the flow restrictor 4 has a rod shape provided in the center of the discharge tube 1 and makes the gas flow rate at the center zero. The flow restrictor 4 is a round bar, that is, a bar having a circular cross section, is coaxial with the discharge tube 1 and extends in the axial direction. The flow restrictor 4 is also made of a dielectric such as quartz glass. The upper end of the flow restrictor 4 is hemispherical, but may be formed in a conical shape. The flow restrictor 4 extends to the same position as the lower end of the discharge tube 1.

The plasma processing system shown in FIG. 1 includes a processing chamber 5 that is an airtight vacuum chamber, an exhaust system 51 that exhausts the inside of the processing chamber 5, and a substrate that holds a substrate 10 to be processed at a predetermined position in the processing chamber 5. And a holder 6. The processing chamber 5 has an opening in the upper wall portion, and the lower end of the discharge tube 1 is fitted in the opening in an airtight manner.

  In FIG. 1, the gas supply system 2 supplies gas into the discharge tube 1 with the high frequency power supply 32 being operated. The supplied gas flows in the discharge tube 1. At this time, a high frequency magnetic field is induced in the discharge tube 1 by the high frequency current supplied to the antenna 31, and the discharge tube 1 is generated by the high frequency electric field induced by the high frequency magnetic field. Discharge occurs in the gas, and the gas is turned into plasma. Active species generated in the plasma enter the processing chamber 5 and reach the substrate 10 to be used for surface treatment. The substrate 10 is held at a position coaxial with the discharge tube 1. This is because the distribution of the active species sent from the discharge tube 1 on the substrate 10 is made uniform and the processing is made uniform.

In the gas activation device in the plasma processing system of this reference example related to the configuration and operation described above, the gas activation efficiency is increased by the action of the flow restrictor 4. Hereinafter, this point will be described.
FIG. 2 is a diagram schematically showing the flow velocity distribution of the gas in the discharge tube 1. The gas flow velocity distribution in the discharge tube 1 is slightly different depending on whether the gas flow is laminar or turbulent. In the case of laminar flow, as shown in FIG. 2 (1), a parabola that is convex in the tube axis direction is drawn. In the case of turbulent flow, as shown in FIG. 2 (2), although it becomes low at the end of the flow path, it has a substantially uniform velocity distribution. Whether the flow is laminar or turbulent depends on the gas pressure, the flow velocity, the shape of the flow path, and the like. In any case , according to this reference example , the gas does not flow in the central portion of the discharge tube 1 but flows only in the peripheral portion with high activation efficiency. For this reason, the whole activation efficiency (activation amount with respect to the whole gas supply amount) can be made high.

How the plasma density distribution varies depending on the pressure will be described with reference to FIG. FIG. 3 shows the relationship between the pressure in the reference example shown in FIG. 1 and the plasma density distribution in the discharge tube 1. In this reference example , the flow restrictor 4 prevents the gas from flowing into the central portion of the discharge tube 1. Therefore, as shown in FIG. 3, when the pressure is low, the plasma density is low, but basically the distribution has the same shape. Therefore, it is possible to effectively increase the plasma density by increasing the pressure to an appropriate value, and the overall activation efficiency can be effectively increased.

Next, the gas activation apparatus in the plasma processing system of the second reference example having a further optimized configuration will be described with reference to FIG. FIG. 4 is a schematic front sectional view of the main part of the gas activation device in the plasma processing system of the second reference example . In this reference example , a cooling system 7 that cools the flow restrictor 4 is provided, and the mounting structure of the flow restrictor 4 is optimized.

  First, the upper end portion of the discharge tube 1 has a flange shape, and a gas introduction plate 21 is provided thereon. The gas introduction plate 21 is attached to the discharge tube 1 in an airtight manner. The gas introduction plate 21 has a circular opening at the center. And the groove | channel 211 is formed in the circumferential direction along the edge of opening horizontally. The gas introduction plate 21 includes a first gas guide passage 212 provided so that the groove 211 and the outer surface communicate with each other, and a second gas extending downward from the groove 211 and reaching the lower surface of the gas introduction plate 21. A gas introduction path 213. The outlet of the second gas introduction path 213 faces the inside of the discharge tube 1. A plurality of second gas introduction paths 213 are provided on the circumference coaxial with the discharge tube 1 at equal intervals. The groove 211 functions as a so-called gas reservoir.

The central opening of the gas introduction plate 21 is provided at a position coaxial with the discharge tube 1, and the flow rate restrictor 4 is provided so as to be fitted in the opening in an airtight manner. Therefore, the groove of the gas introduction plate 21 is in a state of being airtightly closed by the flow restrictor 4. The flow restrictor 4 also has a flange shape at the upper end, and this portion rides on the gas introduction plate 21.
The flow restrictor 4 has a cavity 41 through which a refrigerant flows. As shown in FIG. 4, the cavity 41 is long in the vertical direction, and the upper side reaches the upper end surface to form an opening 42. This opening 42 is for inflow of refrigerant (hereinafter referred to as refrigerant inlet). The lower end of the flow restrictor 4 is closed, but has a refrigerant outlet 43 at a position slightly above the lower end.

The discharge tube 1 also has a refrigerant discharge port 11 at the same height as the refrigerant outlet 43 and at the same circumferential position. The two refrigerant discharge ports 43 and 11 are connected by a refrigerant discharge pipe 71.
The cooling system 7 introduces the refrigerant from the refrigerant introduction port 42 and discharges the refrigerant from the refrigerant discharge port 43, so that the flow rate regulating tool 4 is used. As the refrigerant, water or another refrigerant having a low melting point is used. The cooling system 7 may include a circulator that recools and circulates the discharged refrigerant.
Further, as can be seen from the structure shown in FIG. 4, the flow restrictor 4 is held only on the upstream side of the gas. When trying to hold on the downstream side, a holding member is likely to be provided in the flow path, and the structure tends to shield the flow of active species generated by dissociation, excitation, or the like. In this reference example , there is no such problem.

In this reference example , the gas supply system 2 supplies gas to the discharge tube 1 through the first gas introduction path 212, the groove 211, and the second gas introduction path 213 in the gas introduction plate 21. The supplied gas is transported through the discharge tube 1 and turned into plasma by high-frequency power, and desired dissociation, excitation, etc. occur in the plasma. The discharge tube 1 is heated by plasma and, in some cases, induction heated by high frequency, but is cooled by a cooling system 7. For this reason, the temperature does not rise above the limit. The gas introduction plate 21 is preferably formed of a dielectric so as not to disturb the introduction of high frequency, but may be formed of a conductor depending on the position of the antenna 31 and the like.

Next, a third reference example of the present invention will be described. FIG. 5 is a schematic front sectional view of a gas activation device in the plasma processing system of the third reference example . In the reference example shown in FIG. 5, the flow restrictor 4 divides the inside of the discharge tube 1 into a central channel and a peripheral channel. The flow restrictor 4 has a cylindrical shape and is provided at a position coaxial with the discharge tube 1.
The gas supply system 2 has different gases for a flow path (hereinafter referred to as an inner flow path) in the flow restrictor 4 and a flow path (hereinafter referred to as an outer flow path) inside the discharge tube 1 and outside the flow restrictor 4. To supply. The lower end of the flow restrictor 4 is at the same height as the lower end of the discharge tube 1 or at a lower position. Therefore, the gas flowing in the inner flow path and the gas flowing in the outer flow path are introduced into the processing chamber 5 without being mixed.

In this reference example , since different gases are caused to flow in the discharge tube 1 where the high induced current easily flows and where it is difficult for the current to flow, such a difference can be effectively used. In other words, gas that wants to lower the degree of dissociation or excitation or keep activity low flows through the inner flow path, and gas that wants to increase the degree of dissociation or excitation or higher activity flows to the outer flow path It is usage.

This gas activation apparatus is suitably mounted on a plasma CVD apparatus that forms a silicon nitride film using, for example, silane gas (SiH ₄ or the like) and nitrogen gas. In this type of film formation, a high-quality thin film can be formed by supplying a large amount of active species having a low degree of dissociation such as SiH _{3 to} the substrate 10, but high density plasma is required because nitrogen is difficult to dissociate. Therefore, silane gas (SiH ₄ or the like) is allowed to flow through the inner flow path, and nitrogen gas is allowed to flow through the outer flow path. In the inner flow path, excessive dissociation of silane gas is suppressed, and active species having a low dissociation degree such as SiH ₃ are generated in abundance. In the outer channel, nitrogen is efficiently dissociated by the high-density plasma, and abundantly generated nitrogen active species such as atomic nitrogen and nitrogen ions are generated. When these active species reach the substrate 10, a high-quality silicon nitride film is formed on the substrate 10. In addition, when the structure in which the gas mixture of silane and nitrogen is simply supplied into the discharge tube 1 as in the prior art, in addition to the problem that a high-quality film cannot be obtained, excessive dissociation of silane occurs in the gas phase. There is a problem in that a large amount of polymerization occurs, and the film formation rate on the substrate 10 decreases, or a lot of film deposition occurs on the tube wall or the like.
In the above case, a structure in which a gas whose degree of dissociation, excitation, or activation is desired to be introduced directly into the processing chamber 5 without passing through the discharge tube 1 is also conceivable. However, in this case, there is a drawback that the gas introduction is not completely axisymmetric with respect to the substrate 10 and the gas distribution on the substrate 10 tends to be non-uniform.

Next, a fourth reference example of the present invention will be described. FIG. 6 is a schematic front sectional view of a gas activation device in the plasma processing system of the fourth reference example . In the apparatus shown in FIG. 6, a magnet 8 for setting a magnetic field is provided in the discharge tube 1. The magnet 8 suppresses the movement of electrons toward each wall surface by setting magnetic lines of force in the direction intersecting the flight path of electrons to the wall surface of the discharge tube 1 and the wall surface of the flow restrictor 4 when no magnetic field is provided, Furthermore, the plasma density is increased. Electrons in the plasma are captured by the magnetic field lines, and movement in the direction crossing the magnetic field lines is suppressed. For this reason, it is suppressed that an electron and ion recombine in the vicinity of a tube wall, and plasma is extinguished. Moreover, since the movement of electrons is promoted by the magnetic field, the ionization efficiency of the neutral gas is increased. For this reason, the plasma density can be further increased. The magnetic field intensity may be about several tens of gauss to several hundred gauss.
In FIG. 6, the magnet 8 is drawn as an electromagnet, but it can be constituted by a permanent magnet. Moreover, in FIG. 6, although it is set as the magnetic force line extended along the axial direction of the discharge tube 1, it may be set as the magnetic force line along the circumferential direction surrounding a shaft.

Next, an embodiment of the present invention will be described. FIG. 7 is a schematic front sectional view of a gas activation device in the plasma processing system of the embodiment . In the embodiment shown in FIG. 7, the flow restrictor 4 is made of a conductor such as aluminum, stainless steel, or copper, and is insulated from the ground by an insulating portion (not shown).
As described above, in inductively coupled plasma, a magnetic field is induced by a high-frequency current flowing through the antenna 31, and a current is induced in the plasma by this magnetic field. In FIG. 7, as long as the plasma between the tube wall of the discharge tube 1 and the flow restrictor 4 is inductively coupled to the antenna 31, an induced current flows there even if the flow restrictor 4 is a conductor. That is not essential. Even if an induced current flows, the power loss is only Joule loss. In the case of the metal as described above, this Joule loss is also small. Therefore, there is no problem even if the flow restrictor 4 is made of a conductor as in this embodiment. In this case, the surface of the flow restrictor 4 may be anodized or covered with a dielectric protective film for protection from plasma or the like.

In this embodiment, an end plate 91 is attached to the lower end of the flow restrictor 4. The end plate 91 is a disk-shaped member that is coaxial with the flow restrictor 4. The diameter of the end plate 91 is smaller than the diameter of the lower end opening of the discharge tube 1, and therefore a gap is formed between them. Chemical species generated by activation in the discharge tube 1 flow out through this gap and reach the substrate 10 in the processing chamber 5.
The end plate 91 is insulated from the ground by an insulating portion (not shown), similarly to the flow restrictor 4, and has a floating potential. The floating potential is a negative potential as is well known. The end plate 91 having a floating potential has a function of making the plasma more dense by preventing diffusion of electrons through the lower end opening of the discharge tube 1. If a large amount of electrons, particularly electrons captured by the magnetic field lines set by the magnet 8, diffuse from the opening of the discharge tube 1, there is a problem that the plasma diffuses and the plasma density decreases. In this embodiment, since the end plate 91 having a floating potential is provided, diffusion of electrons through the opening is suppressed at this portion. For this reason, plasma can be made more dense.

  The end plate 91 also has a function of adjusting the conductance of the opening of the discharge tube 1. The conductance value is adjusted by appropriately selecting the diameter of the end plate 91. The reason why the conductance is reduced by the end plate 91 is to generate high-density plasma in the discharge tube 1 while keeping the pressure in the processing chamber 5 low. As described above, in order to generate high-density plasma, it is effective to increase the pressure in the discharge tube 1. However, since the discharge tube 1 and the processing chamber 5 are in communication, the discharge tube 1 When the internal pressure is increased, the pressure in the processing chamber 5 is likely to increase. Depending on the process, it may be necessary to process at a low pressure, which is inconvenient. Therefore, in the present embodiment, the end plate 91 is provided to reduce the conductance between the discharge tube 1 and the processing chamber 5 so that a large pressure difference is generated. For this reason, the inside of the processing chamber 5 can be kept at a predetermined low pressure while generating a high-density plasma by relatively increasing the pressure in the discharge tube 1.

  For example, the end plate 91 can make the inside of the discharge tube 1 about 100 to 500 Pa and the inside of the processing chamber 5 about 1 to 10 Pa. Note that a flow rate regulator (not shown) of the gas supply system 2 controls the flow rate to be constant. Therefore, even when the conductance becomes small, the flow rate of the chemical species flowing out from the discharge tube 1 is constant, and the efficiency does not decrease.

Next, a fifth reference example of the present invention will be described. FIG. 8 is a schematic front sectional view of a gas activation device in the plasma processing system of the fifth reference example. In the embodiment shown in FIG. 8, a conductance adjuster 92 is provided at the boundary portion between the discharge tube 1 and the processing chamber 5. The conductance adjuster 92 is attached to the lower end of the discharge tube 1. The conductance adjuster 92 has a shape in which a circular opening is provided in the center of a circular plate, and has a shape that reduces the area of the lower end opening of the discharge tube 1. The function of the conductance adjuster 92 is the same as one of the functions of the end plate 91 in the embodiment. That is, it is possible to adjust while reducing the conductance by appropriately selecting the opening area of the discharge tube 1. In the fifth reference example , the conductance adjuster 92 is made of a dielectric or a conductor insulated from the ground, and may be a grounded conductor as long as the induced current does not flow essentially. .

The application field of the gas activation device includes a cleaning device, an exhaust gas treatment device, a fine powder generation device and the like in addition to the above-described CVD and etching. The cleaning device is a device that performs cleaning to remove surface deposits by the action of active species and ions generated by activation in plasma. An exhaust gas treatment device is a device that activates harmful exhaust gas using plasma to render it harmless. The fine powder generation apparatus is an apparatus that generates a fine powder by activating a raw material gas by plasma and polymerizing or growing crystals in a gas phase.

It is a front section schematic diagram of a gas activation device in a plasma treatment system of the 1st reference example . FIG. 3 is a diagram schematically showing a flow velocity distribution of gas in the discharge tube 1. The relationship between the pressure in the reference example shown in FIG. 1 and the plasma density distribution in the discharge tube 1 is shown. It is a front cross-sectional schematic diagram of the principal part of the gas activation apparatus in the plasma processing system of the 2nd reference example . It is a front section schematic diagram of the gas activation device in the plasma treatment system of the 3rd reference example . It is a front section schematic diagram of the gas activation device in the plasma treatment system of the 4th reference example . It is a front section schematic diagram of a gas activation device in a plasma treatment system of an embodiment . It is a front section schematic diagram of a gas activation device in a plasma treatment system of the 5th reference example . It is a front cross-sectional schematic diagram of the gas activation apparatus of the prior art example which employ | adopted the inductively coupled plasma system. FIG. 10 is a diagram showing the relationship between gas pressure and plasma density in the conventional gas activation device as shown in FIG. 9.

DESCRIPTION OF SYMBOLS 1 Discharge tube 2 Gas supply system 31 Antenna 32 High frequency power supply 4 Flow control tool 5 Processing chamber 51 Exhaust system 6 Substrate holder 7 Cooling system 8 Magnet 91 End plate 92 Conductance adjustment tool 10 Substrate

Claims (4)

A discharge tube, a processing chamber communicating with the discharge tube through an opening, a gas supply system for supplying a gas into the discharge tube, and a high frequency for generating inductively coupled plasma by applying high frequency power to the gas in the discharge tube A power application mechanism, a flow rate regulator provided in the discharge tube so as to increase the gas flow rate in the peripheral portion compared to the central portion, and an end plate attached to one end of the flow rate adjuster,
The end plate has a floating potential,
A gap between the end plate and the discharge tube is formed with a gap through which the gas flows toward the processing chamber. The plasma processing system according to claim 1, wherein the flow restrictor has a shape extending along an axis of the discharge tube and is provided coaxially with the discharge tube. A magnet for setting a magnetic field is provided between the tube wall of the discharge tube and the flow restrictor, and this magnet is used to prevent electrons on the wall of the discharge tube and the wall of the flow restrictor when no magnetic field is provided. 2. The plasma processing system according to claim 1, wherein magnetic lines of force are set in a direction crossing the flight path to suppress movement of electrons toward each wall surface. A plasma processing method using a plasma processing system according to any claims 1 to 3, by adjusting the conductance by the end plate, while the pressure in the discharge tube and higher than the pressure in the processing chamber treatment Performing a plasma processing method.

Images