JP2001035692A - Discharge vessel and plasma radical generator with the discharge vessel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a plasma radical generator capable of generating radicals under discharged plasma condition at high efficiency. SOLUTION: This device has a discharge vessel 31 for generating radicals with high frequency discharge. The discharge vessel 31 consists of a cathode portion 6 located near an entrance for material gas into which high frequency power is supplied, a jet portion 5 located next to the cathode portion 6 and having a smaller sectional area than that of the cathode portion 6, and an anode portion 7 located next to the jet portion 5 and having a larger sectional area than that of the jet portion 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma radical generator for efficiently generating radicals or excited species of a gas excited by a high-frequency discharge.

[0002]

2. Description of the Related Art For example, when depositing a thin film on the surface of a semiconductor substrate, a vacuum deposition method, a sputtering method, a chemical vapor deposition method, a molecular beam epitaxy method and the like are used. In this case, in any of the methods, for example, a raw material gas (hereinafter, simply referred to as “raw material”) is deposited on a target surface in a molecular or atomic state. At this time,
In order to make the raw material molecular or atomic, the raw material is decomposed and used by energy such as heat, light, ions, and excited species (radicals).

[0003] In the case where the raw material is decomposed into molecules or atoms as described above, a method of decomposing the raw material by plasma is known. In this case, the plasma source is located apart from a processing unit such as a thin film, and this is called a remote plasma method. FIG. 12 shows a schematic configuration relating to the remote plasma method. In the remote plasma method, as shown in FIG. 12A, the source gas 12 is excited by high-frequency electric power 62, but ions and ions are generated by separating the plasma generation unit (plasma source) 43 and the processing unit (process container) 17 from each other. There is no damage to the processing unit 17 due to the collision of electrons. The processing unit 1
7, a process gas is introduced, and the plasma
Reacts with the radicals 13 generated in step (1) to produce a reactant 20. This remote plasma method is also a method that can prevent damage to ultraviolet rays by using an optical trap in some cases. This is performed by bending the radical transport tube 8 as shown in FIG.

[0004] There are many reports on the remote plasma method by Hatanaka et al. (Bulletin of the Research Institute)
tute of Electronics Shizuoka University, Vol. 29,
pp.87-94, 1994), and various plasma sources have been studied. For example, high-frequency inductively coupled devices, and those in which high power of several kW is applied to these devices by S. Wickramanayaka et al. To generate radicals in a highly excited state (Jpn. J. Appl. Phys., Vol. 30, pp. 28
97-2900, 1991). In addition, Nomura et al. Have performed deposition of a thin film by remote plasma in a low pressure region by a plasma source using electron cyclotron resonance (J. Appl. Phys. 69, pp. 990-993, 1991). Also, Horowitz (J. Vac. Sci. Tech. A6 (3), pp. 1837-
1844 (1988)) reported that a high-density plasma was obtained by the holocathode method. The one using a large number of hollow cathodes is reported in Vacuum 36, pp. 837-840 (1986). Bardos et al. CVD single jet plasma
(Chemical Vapor Deposition) method (Thin Sol
id Films 158, pp. 265-270 (1988)). But Bardos
Although they discharge the film between the cathode and anode conductive containers having small orifices and deposit the film on the substrate, they can deposit the film only in a small area.

Have disclosed a hollow cathode type discharge plasma source (Surface a) comprising a cathode having one or more holes in a jet region and an anode surrounding the cathode.
nd Coatings Technology 93, pp. 128-133 (1997)). This main part is all made of conductive metal and is a plasma source that can cover a large area.However, the jet part may be electrically coupled through the plasma potential, and the hole of the jet area described above causes the plasma to be generated. The strength becomes uneven. Nor has the problem of metal contamination been solved. In addition, there is a disadvantage that a loss portion occurs in which the input gas does not necessarily flow through the hole of the jet and flows out.

[0006]

As described above, in the generation of radicals (including excited species; hereinafter simply referred to as "radicals") by a conventional plasma source, there is a problem that a high yield of radicals cannot be generated. Have a point.

The present invention has been made in view of the above circumstances, and has as its object to provide a plasma radical generating apparatus for obtaining radicals from a discharge plasma state with high efficiency. In the present invention, radicals can be used not only for CVD, but also for cleaning or etching or modifying a solid surface. The plasma generator of the present invention is classified as a high-frequency hollow cathode plasma source.

[0008]

According to the present invention, the following means have been taken in order to solve the above-mentioned problems.

The present invention derives an extremely large effect by devising a jet part in a simple hollow cathode type high frequency plasma discharge. That is,
The plasma radical generator of the present invention is a plasma radical generator including a discharge vessel that generates radicals by high-frequency discharge, wherein the discharge vessel is located near an inlet of the source gas, and high-frequency power is supplied to the source gas. A cathode portion, a jet portion located at the next stage of the cathode portion and having a smaller cross-sectional area than the cathode portion,
An anode portion located next to the jet portion and having a larger cross-sectional area than the jet portion. Here, the high-frequency discharge is generated between the capacitively coupled electrodes, and is intended for a high-frequency discharge of approximately 1 MHz to 100 MHz, and efficiently generates radicals of a gas excited by the high-frequency discharge.

In this plasma radical generator,
The preferred embodiment is as follows.

(1) The discharge vessel is made of an insulator with a small recombination of radicals. As described above, the discharge vessel includes a cathode portion provided with an electrode to which power is supplied, an anode portion, and a jet portion connecting the both. Here, the jet portion has a specific relationship with the size of the cathode and the anode, and is several mm to several c.
m and the diameter of the cathode and the anode are several cm to several tens cm.

(2) A matching circuit, which is arranged close to the cathode electrode arranged in the cathode section so as to sandwich the anode electrode arranged in the anode section and supplies electric power for generating a discharge. To have more.
In addition, a shield box is provided in the discharge part, and the shield box has the same potential as the anode and is arranged so as to surround the whole. Further, the gas input section and the gas output section shall be connected by making holes in the casing of the shield box.

(3) The cross-sectional area at the inlet of the source gas is smaller than the cross-sectional area of the jet section. By doing so, the gas flow velocity at the entrance is increased, and plasma can be prevented from flowing out to the gas entrance side. Further, instead of simply reducing the cross-sectional area of the entrance, a capillary structure such as bundling thin tubes may be used. The material of the capillary is preferably an insulator. The capillary may be a tube or a bead.

(4) The discharge vessel is an electrically insulating material such as quartz, alumina, Pyrex glass, Teflon, silicon nitride, aluminum nitride and the like.

(5) The jet part of the discharge vessel has a structure capable of air cooling or water cooling.

(6) The discharge vessel is cylindrical.

(7) The anode and the cathode in two or more discharge vessels can supply power as a common anode and cathode. At this time, a large number of discharge vessels can be supplied with the same power supply in a line. Further, the discharge vessels are arranged in a plane so that the anode part and the cathode part can be commonly supplied with power.

According to the plasma radical generating apparatus of the present invention, it is cheaper and simpler than microwave excitation, has a simpler and cheaper structure than inductively coupled high-frequency excitation, and has an extended arrangement such as arranging or arranging a plurality of discharge vessels. It has the advantage of high performance. Further, compared to a helicon plasma or an electron cyclotron resonance plasma excitation device, it is light in weight, simple in structure and inexpensive without using a magnetic field. Furthermore, compared with a simple conventional holocathode plasma source, the present invention has an effect that high-density radicals can be obtained from the jet part.

According to the present invention, since all the gas passes through the narrow area of the jet portion, this narrow area becomes high-density plasma, and radicals with high efficiency and high excited state can be obtained, and power consumption is small. . Compared with the one without the jet part, the plasma radical generator of the present invention at a power of 50 W is equivalent to other plasma radical generators at a power of 200 W or more.

In the anode region according to the present invention, that is, the plasma potential at the outlet of the plasma source can be set to a low value, and the diameter of the outlet can be increased, so that the area of the uniform radical source can be increased. The insulator container according to the present invention is capable of taking out and transporting high-density radicals to a distant place by using one having a small radical recombination coefficient.

Furthermore, radicals excited to a high level can have a long lifetime, and can be expected to have a special effect in CVD or the like, particularly in high-density thin films, high-quality thin films, and improved deposition rates.

Further, the presence of the jet portion makes it possible to make a difference between the pressure of the anode portion and the pressure of the cathode portion, so that the structure becomes a convenient structure as a radical source when processing is required at a higher vacuum. ing.

Considering a pair of electrodes of the same cylindrical type, the length of the cylinder is such that the electric field cannot penetrate into the inside from the end of the cylinder. An electric field is concentrated between the plasma and the plasma, and power is consumed mainly here. Electrons are efficiently ionized by reciprocating between the electrode side and the plasma side to generate high density plasma. However, the present invention is not concerned with this general holocathode effect, but by adding a jet region of small diameter, the density of the plasma is increased in this region, and all gases pass through this region and the efficiency is increased. It is able to generate radicals well. Thereby, the above-described effects can be obtained.

[0024]

Embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a diagram showing a schematic configuration of a plasma radical generator according to one embodiment of the present invention. In addition,
To clarify the difference between the device of the present invention and the conventional device,
FIG. 2 shows a schematic configuration of a conventional plasma radical generator. As is clear from FIGS. 1 and 2, the plasma radical generator according to the present invention has a configuration in which a jet unit and an anode unit are added, as compared with the conventional device. This will be described in detail below.

In FIG. 1, a discharge vessel 31 comprises a gas input section 9, a cathode section 6, a jet section 5, and an anode section 7, and radicals generated in the discharge vessel 31 are transported through a transport pipe section 8. The process is guided to a process unit (not shown) (to be described in detail later). The wall material of the discharge vessel 31 is preferably made of a material having a small surface recombination. The gas inlet 9 is made of the same material as that of the discharge vessel 31.
It has a smaller cross-sectional area. The details of the gas inlet 9 will be described later. In the cathode section 6 and the anode section 7, a cathode electrode 10 and an anode electrode 11 are provided around the discharge vessel 31, respectively. A high-frequency voltage is applied to the cathode electrode 10 by a high-frequency power source 14.
And the anode electrode 11 is connected to the ground potential 15. In the embodiment, the anode electrode 11 is grounded. However, the anode electrode 11 may not be grounded, and may have a fixed potential such that the cathode electrode 10 and the anode electrode 11 are efficiently coupled. It should just be fixed to. Thus, the anode part 7
, A strong jet discharge can be generated. Since the hollow cathode plasma is generated by the high-frequency voltage supplied from the high-frequency power supply 14, the frequency is preferably approximately 1 MHz to 100 MHz.

The operation of the plasma radical generator configured as described above will be described in detail below.

The raw material gas 12 led to the gas input section 9 passes through the cathode section 6, passes through the jet section 5, the anode section 7 and the transport pipe section 8, and is coupled to the process section.

Hollow cathode plasma is generated in the cathode section 6, and the pressure in the cathode section 6 is determined by the discharge starting voltage of the hollow cathode. Electric power is supplied to the high-density hollow cathode plasma 2 by capacitive coupling between the cathode electrode 10 and the cathode wall 6a, which are fed by the high frequency power supply 14. The electron current 32 generated by the capacitive coupling reaches the anode plasma section 3 and the anode wall 7a through the jet section 5. In the present invention, the jet unit 5
To increase the radical generation efficiency in the jet unit 5 as compared with the conventional case. The reason is as follows.
In the jet unit 5, the electron temperature (that is, the velocity of the electrons)
Is large, and the excitation energy in the case of collision excitation (where the electron acceleration electric field is strong) is large, so that it can be considered that it can be excited to a high excited state. The plasma in the anode plasma section 3 passes through the remote plasma section 4 and is introduced into the processing section, where predetermined processing is performed.

FIG. 3 shows an equivalent circuit of the plasma radical generator of the present invention configured as described above.

According to FIG. 3, all the power is
(Ie, cathode wall 6 a) and must flow through jet 5. When the impedance 40 of the anode electrode 11 is small, high density jet plasma is generated. The current from the anode plasma section 3 is mainly grounded from the anode electrode 7 through the capacity of the anode wall 7a. When the capacity of the anode unit 7 is large, the impedance 40 is low, and the plasma potential on the anode unit 7 side can be low.
If the electrode capacity 36 is small, the plasma potential becomes large, and a current flows into a process vessel (not shown), which directly acts as plasma. Compared with the plasma resistance 38 of the transport pipe section, the capacitance impedance 40 of the anode plasma section 3 is smaller than that of the transport pipe section 8.
Can be realized when the impedance 38 is high or when the anode capacity 36 is large. In order to have sufficient capacity, for example, the anode electrode 11 must be equal to or longer than the length of the cathode electrode. Anode wall 7
The thickness of a must be equal to or less than the thickness of the cathode wall 6a. However, wall thickness limitations are limited by mechanical strength.

In the present invention, the most efficient conversion efficiency is obtained when a major part of the total impedance is represented by the impedance 37 of the jet section. This means that the impedance 39 of the cathode plasma section 2
This means that the impedance 40 of the anode plasma section 3 must be sufficiently small. At this time, the ratio (Lc / Lc) of the length and the diameter of the cathode portion 6 shown in FIG.
dc) is small enough, that is, less than 2 in a typical example. The pressure at the anode section 7 is always lower than at the cathode section 6, and the mean free path of electrons at that section is longer. Therefore, the ratio (La / da) between the length and the diameter of the anode section 7 is larger than that of the cathode section 6, and the optimum value is approximately 2 to 4.

As a method for increasing the plasma impedance of the jet portion, a ratio of the length to the diameter (L
j / dj). However, when the jet unit 5 is fine and long, it becomes difficult to start discharge, so that the ratio cannot be set to a predetermined value or more. The reason for this is that, as the diameter becomes smaller, the electrons are involved in recombination, which limits the acceleration of the electrons and makes it difficult for the current to flow. If the diameter is too small, the pressure in the cathode region increases, the mean free path of electrons becomes small, and the hollow cathode effect cannot be expected. As a result, it is necessary to reduce the diameter of the cathode portion 6, but at this time, the diameter of the cathode electrode 10 is reduced, and the overall efficiency of plasma generation is reduced. Empirically, it is desirable that the diameter of the jet unit 5 be about 3 in the pressure difference between the cathode and the anode. The optimum diameter of the cathode section 6 is determined based on the conditions under which the hollow cathode effect can be obtained, but it depends on the type of gas and the pressure. In the case of a molecular gas such as hydrogen, nitrogen, or oxygen, the cathode diameter is 2 to 4 cm when the cathode section 6 is, for example, about 1 Torr, and about 8 to 4 cm when the cathode section 6 is about 0.1 Torr. 10 cm. The pressure of the discharge vessel 31 is 0.1 Torr, 1 Torr
FIG. 5 shows an example of the size of each part in the case of r and 10 Torr. Here, the wall pressure of the discharge vessel 31 is 2.5 mm. As shown in FIG. 5, the jet part has a specific relationship with the size of the cathode and the anode, and is several mm.
And a length and a diameter of several cm, and the cathode and the anode are preferably several cm to several tens cm.

Next, the inlet 9 through which the raw material gas 12 is introduced into the discharge vessel 31 will be described. At the input section 9 of the source gas 12, partial discharge may occur in the connection pipe 29 shown in FIG. The input gas line 47 is usually a conductor such as a stainless steel tube, and is usually grounded. Here, the connecting pipe 29 is excited by the cathode plasma 2, and a discharge occurs between the connecting pipe 29 and the gas line 47. The discharge generated here spreads to the gas line 47,
Since accidents can occur, measures to prevent this discharge are essential.

A method of avoiding the discharge at the gas input unit 9 is to make the diameter (that is, the sectional area) of the input unit 9 sufficiently smaller than the diameter of the jet unit. One example is 1mm
The following is effective. Thus, the input unit 9
If the diameter is reduced, the gas flow rate is restricted, and backflow of the plasma in the inlet direction is prevented, so that the discharge does not reach the gas line. Therefore, as shown in FIG. 6 (b), the objective can be achieved by inserting a capillary in which thin tubes are bundled to reduce the cross-sectional area through which gas passes. Here, the capillary 49 is placed inside the connecting pipe 29 with the insulator 30.
Is fixed in the protective tube 50 inside. Further, the capillary 49 may be manufactured using a bead-shaped one.

The discharge vessel 31 is preferably an electrically insulating material such as quartz, alumina, Pyrex glass, Teflon, silicon nitride, aluminum nitride or the like. I just want it. Further, since the temperature of the jet part 5 of the discharge vessel 31 is likely to be high, it is preferable that the jet part 5 has a structure capable of air cooling or water cooling.

Hereinafter, an example in which the above-described discharge vessel 31 of the plasma radical generating apparatus according to the present invention is applied will be described.

(Application Example 1) FIG. 7 shows a configuration of a process apparatus to which the discharge vessel 31 of the plasma radical generator of the present invention is applied. Although the above embodiment has been described with particular emphasis on the discharge vessel 31, FIG. 7 also shows peripheral devices (for example, a power supply, a shield box, and a process unit).

In FIG. 7, the supplied high frequency power is
When grounded closest to the cathode electrode 10, the power efficiency is highest. The matching circuit 42 including the capacitance 22, the load capacitance 23, and the coil 24 of the matching circuit 42 is arranged around the jet unit 5, the cathode unit 6, and the anode unit 7 of the discharge vessel 31. High frequency power is applied from the plug 21. The tuning of the variable capacitors 22 and 23 is performed by the rotating shafts 22a and 23a, respectively. The coil is divided into two parts as shown, so that the spatial arrangement is well balanced. This is a very compact and efficient arrangement.

The plasma radical transport tube 8 connects the plasma source 43 to the process vessel 17. The process vessel 17 is placed near a substrate support 18 with a substrate 19. Distribution system 4 for dispersing process gas 44
By introducing the process gas 44 through 5, the scientific energy and physical energy of the radicals are consumed as energy for the decomposition of the process gas. The reaction product 20 is collected by a vacuum pump 46. FIG. 8 shows the measurement results of hydrogen radicals from this plasma device. FIG. 8 is a diagram showing a comparison between the concentration of radicals when using the ordinary hollow cathode plasma apparatus and the concentration of radicals when using the apparatus according to the present invention. In this measurement, NO ₂ gas was used as a titration gas, radicals were transported from the output end of the hollow cathode through the glass tube, and the titration gas was injected at several points along the way. FIG. 8 shows that the radical according to the present invention has little attenuation and a long life. This means
It is interpreted as a result that a higher excited state can be obtained. In addition, this radical source has a power efficiency of 1.6 times when used near, and a power efficiency of 4 times when used far. This result is a useful result as a radical source.

(Application Example 2) An application example in which one discharge vessel 31 according to the present invention is used in a process is shown in Application Example 1 described above.
However, a plurality of discharge vessels 31 can be used in a line. FIG. 9 shows a discharge vessel 31 (31a).
-31e) shows a case where a plurality of -31e) are arranged in a line. FIG.
In FIG. 7, the same portions as those in FIG. 7 are denoted by the same reference numerals, and detailed description will be omitted. In FIG. 9, each discharge vessel 31a
-31e are connected in such a manner that the electrodes of the anode section and the cathode section are shared, so that the anode electrode 52 and the cathode electrode 51 are shared and a high frequency is applied to only the cathode electrode 51 by one power supply 14.
Powered by By doing so, an impedance matching circuit (not shown) can be adjusted by one matching circuit. Also, all the discharge vessels 31 are connected to the same process vessel 17,
By moving the substrate fixing table 18 in the inside, a large-area thin film deposition or plasma processing apparatus can be manufactured.

FIG. 10 is a view taken along the line AA of FIG.
This shows a method of continuously forming a cathode and an anode using a strip-shaped stripe electrode. For example, by configuring the discharge vessel to be sandwiched between strip-shaped copper or the like, the electrodes can be easily shared. For example, as shown in FIG. 10, the discharge vessel is sandwiched between the upper electrode strip 56 and the lower electrode strip 55 so that the upper and lower electrode strips 55 and 56 are commonly connected to a plurality of discharge vessels. are doing. Here, the diameters of all the cathode walls 57a-57e, the diameters of the anode walls 58a-58c,
And the thickness of the container is preferably of the same dimensions. Further, it is preferable that the diameters of the jet walls 59a to 59c are the same. Also, the jet sections 59a-59c must have the same dimensions.

The method of sharing the electrodes of the plurality of discharge vessels 31 shown in FIG. 10 and simultaneously supplying power to the cathode electrode and the like is as follows.
It can be extended in a two-dimensional plane. Figure 1 shows an example of the layout
1 (a) and FIG. 11 (b). This is an example of an arrangement for connecting the strip electrodes without cutting them.

The present invention is not limited to the above embodiments of the present invention, but can be, of course, carried out in various modifications without departing from the spirit of the present invention.

[0045]

According to the present invention, the following effects can be obtained.

As described above, according to the plasma radical generator of the present invention, highly efficient and high-density radicals can be generated with a simple configuration.

[Brief description of the drawings]

FIG. 1 is a diagram showing a schematic configuration of a plasma radical generator according to an embodiment of the present invention.

FIG. 2 is a diagram showing a schematic configuration of a conventional plasma radical generator.

FIG. 3 is a diagram showing an equivalent circuit of the plasma radical generator of the present invention.

FIG. 4 is a diagram showing symbols related to the size of the plasma radical generator of the present invention.

FIG. 5 is a diagram showing an example of the size of each part according to the pressure of the discharge vessel.

FIG. 6 is a diagram showing a configuration example of a gas input unit.

FIG. 7 is a diagram showing a configuration of a process apparatus to which a discharge vessel of the plasma radical generator according to the present invention is applied.

FIG. 8 is a diagram showing a comparison of the radical lifetime between a normal hollow cathode type and the plasma radical generator of the present invention.

FIG. 9 is a diagram showing an example in which a plurality of discharge vessels are arranged in a line.

FIG. 10 is a view taken in the direction of arrows AA in FIG. 9 and shows a method of continuously forming a cathode and an anode by using strip-shaped stripe electrodes.

FIG. 11 shows two methods for simultaneously supplying power to a cathode electrode and the like.
The figure which shows the example extended in the two-dimensional plane.

FIG. 12 is a diagram showing a schematic configuration relating to a remote plasma method.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Jet plasma part 2 ... Cathode plasma part 3 ... Anode plasma part 4 ... Remote plasma part 5 ... Jet part 6 ... Cathode part 6a ... Cathode wall 7 ... Anode part 7a ... Anode wall 8 ... Transport pipe part 9 ... Gas input part DESCRIPTION OF SYMBOLS 10 ... Cathode electrode 11 ... Anode electrode 12 ... Raw material gas 13 ... Flow of radicals and excited species 14 ... High frequency power supply 15 ... Ground potential 15a ... Grounding through a process vessel 16 ... Housing supporting a discharge vessel 17 ... Process vessel 18 ... Substrate support 19 ... Substrate 20 ... Reactant 21 ... Power supply connection plug 22 ... Adjustment capacity 22a ... Capacity adjustment axis 23 ... Load capacity 23a ... Load capacity adjustment axis 24 ... Coils 25 ... Adjustment capacity ground connection 26 ... High-frequency power supply coupling 27 ... Cathode coupling of load capacitance 28 ... Connection of anode electrode to housing 29 ... Connection DESCRIPTION OF SYMBOLS 30 ... Insulator 31 (31a-31e) ... Discharge container 32 ... Electron flow 33 ... Container wall of a jet part 34 ... Electric equivalent circuit of plasma with respect to high frequency 35 ... Capacity (capacitance) between cathode electrode and cathode plasma 36 ... Capacitance (capacitance) between the anode electrode and the anode plasma part 37: Impedance of jet part 38: Plasma impedance of transport part 39: Impedance of cathode plasma 40: Impedance of anode plasma 41: Cooling fan 42 ... Matching circuit 40: Plasma Source 44 ... Processing gas 45 ... Distribution system 46 ... Vacuum pump 47 ... Gas line 48 ... Partial discharge 49 ... Insulating capillary tube 50 ... Insulator support tube 51 ... Common cathode electrode 52 ... Common anode electrode 55 ... Lower anode electrode band 5 ... Upper anode electrode band 57 (57a-57e). Container wall 58 (58a-58e) of cathode portion of plasma source connected in line. 59. Container walls 59 (59a-59e) of anode portion of plasma source connected in line. Vessel walls 60 (60a-60e) of jet sections of plasma sources connected in a row 60—Jet plasma connected in a row 61—Optimum value of coupling of high-frequency power supply 62—Electromagnetic energy 63—Gas input port 64—Radical transport pipe section Lr: length of radical transport tube section La: length of anode section Lc: length of cathode section Lj: length of jet section Ar: sectional area of radical transport section Aa: sectional area of anode section Ac: cathode section Cross-sectional area Aj: Cross-sectional area of jet part Ag: Cross-sectional area of gas input part dr: Diameter of radical transport part da: Diameter of anode part dc ... diameter of cathode part dj ... diameter of jet part dg ... diameter of gas input port ta ... thickness of container wall of anode part tC ... thickness of container wall of cathode part

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[Procedure amendment]

[Submission date] March 17, 2000 (2003.
7)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Name of invention

[Correction method] Change

[Correction contents]

Patent application title: Discharge Vessel and Plasma Radical Generator Having the Discharge Vessel

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] Claims

[Correction method] Change

[Correction contents]

[Claims]

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0009

[Correction method] Change

[Correction contents]

The present invention derives an extremely large effect by devising a jet part in a simple hollow cathode type high frequency plasma discharge. That is,
The discharge vessel of the present invention converts plasma radicals from a raw material gas.
A cylindrical discharge vessel for generating the source gas;
Near the entrance of the discharge vessel and outside the discharge vessel.
With a cathode electrode arranged to surround the container.
And a high-frequency power from the cathode electrode to the source gas.
A cathode <br/> over de portion for generating a plasma by supplying, disposed downstream of the cathode unit, the discharge
Placed outside the vessel to surround the discharge vessel
An anode section having an anode electrode , and the cathode section;
The cathode unit is disposed between the anode unit and the anode unit.
The part that joins the anode part and has a constricted structure
And the plug generated by the constricted structure.
Generates high-density radicals by increasing the density of the zuma
And a jetting part . Here, the high-frequency discharge is generated between the capacitively coupled electrodes, and is intended for a high-frequency discharge of approximately 1 MHz to 100 MHz, and efficiently generates radicals of a gas excited by the high-frequency discharge.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0010

[Correction method] Change

[Correction contents]

[0010] In this discharge vessel and the plasma radical generator provided with the discharge vessel , preferred embodiments are as follows.

[Procedure amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0018

[Correction method] Change

[Correction contents]

The discharge vessel of the present invention and the discharge vessel
According to the plasma radical generating apparatus, it is inexpensive and simpler than microwave excitation, simpler and cheaper than inductively coupled high-frequency excitation, and has high expandability such as disposing or arranging a plurality of discharge vessels. Having. Further, compared to a helicon plasma or an electron cyclotron resonance plasma excitation device, it is light in weight, simple in structure and inexpensive without using a magnetic field. Furthermore, compared with a simple conventional holocathode plasma source, the present invention has an effect that high-density radicals can be obtained from the jet part.

[Procedure amendment 6]

[Document name to be amended] Statement

[Correction target item name] 0046

[Correction method] Change

[Correction contents]

As described above, the discharge vessel of the present invention and this discharge vessel
According to the plasma radical generator equipped with a discharge vessel ,
With a simple configuration, radicals of high efficiency and high density can be generated.

Claims (5)

[Claims] 1. A plasma radical generator comprising a discharge vessel for generating radicals by high-frequency discharge, wherein the discharge vessel is located near an inlet of a source gas, and a cathode unit is supplied with high-frequency power to the source gas. A jet section located next to the cathode section and having a smaller cross-sectional area than the cathode section; and an anode section located next to the jet section and having a larger cross-sectional area than the jet section. A plasma radical generator characterized by the following. 2. The plasma radical generating apparatus according to claim 1, wherein a discharge is generated by disposing the cathode electrode disposed on the cathode section and the anode electrode disposed on the anode section so as to sandwich the anode electrode. A plasma radical generator, further comprising a matching circuit for supplying power for performing the operation. 3. The plasma radical generator according to claim 1, wherein a cross-sectional area of an inlet portion of the source gas is:
A plasma radical generator having a capillary structure smaller than the cross-sectional area of the jet portion and having a bundle of thin tubes. 4. The plasma radical generator according to claim 1, wherein the discharge vessel is an electrically insulating material,
A plasma radical generator comprising a material containing any of quartz, alumina, pyrex glass, Teflon, and silicon nitride, wherein a jet part of the discharge vessel has a structure capable of air cooling or water cooling. 5. The plasma radical generator according to claim 1, wherein the plurality of discharge vessels are arranged in a line or in a plane, and the anode and cathode of at least two of the discharge vessels are used as a common anode and cathode. A plasma radical generator, wherein at least two or more of the discharge vessels are supplied with the same power supply by supplying power.