Patent Application
20120037504
The present invention concerns a plasma generation apparatus in which the supply source of the plasma constituent is made to be the cathode, a cylinder-like anode is set up at the front or perimeter of said cathode, and plasma is generated from the surface of said cathode by doing a vacuum arc discharge between said cathode and said anode under a vacuum environment, and a plasma processing apparatus that does plasma treatment such as film formation by anode by means of the generated plasma from said plasma generation apparatus. To be specific, the present invention concerns a multiply divided anode wall type plasma generation apparatus, and a plasma processing apparatus that uses the former.
Normally, it is known that by forming a thin film or injecting ions in plasma onto the surface of a solid material, the solid surface characteristics are improved. A film formed using plasma including metal ions and nonmetal ions strengthens the abrasion and corrosion resistances of a solid surface, and it is useful as a protective film, an optical thin film, and a transparent electroconductive film among others. In particular, as for carbon films using carbon plasma, the utility value is high as diamond like carbon films (so-called DLC films) comprising amorphous mixed crystals of diamond and graphite structures.
As a method for generating plasma including metal ions and nonmetal ions, there is a vacuum arc plasma method. Vacuum are plasma is formed by an arc discharge occurring between a cathode and an anode. The cathode material evaporates from an existing cathode spot of the cathode surface, and it is plasma formed by this vaporized cathode material. Also, when a reactive gas is introduced as the environmental gas, the reactive gas is ionized simultaneously. An inert gas (so-called noble gas) may be introduced together with said reactive gas, and said inert gas can also be introduced instead of said reactive gas. By means of such plasma, a surface treatment can be done by a thin film formation or an ion injection onto a solid surface.
Normally, in a vacuum arc discharge, at the same time as vacuum arc plasma constituent particles such as cathode material ions, electrons, and cathode material neutral atom groups (atoms and molecules) are ejected by a cathode spot, cathode material particles named droplets of size ranging from less than submicron to several hundred microns (0.01-1000 μm) are also ejected. When these droplets adhere to the surface of an object to be treated, the uniformity of a film formed on the surface of the object to be treated surface is lost, a defective thin film is produced, and the surface treatment result of the film formation is affected.
A plasma arc machining apparatus having a droplet collecting portion is disclosed in Japanese Patent Laid-Open No. 2002-8893 bulletin (Patent Document 1).
Plasma 204 ejected from plasma generating portion 200 is bent to a T-shape toward a direction away from plasma generating portion 200 by the magnetic field, and is flowed into plasma processing portion 208. At the position facing plasma generating portion 200, droplet collecting portion 212 is positioned, where cathode material particles (droplets) 213 generated as a byproduct at cathode at the time of generation of plasma 204 are collected. Therefore, droplets 213 not under an influence of the magnetic field advances to droplet collecting portion 212 and are collected, thereby preventing an intrusion of droplets 213 into plasma processing portion 208.
[Patent Document 1] Japanese Patent Laid-Open No. 2002-8893 bulletin
The conventional plasma crafting apparatus uses anode 203 comprising a cylinder-shaped electrode cylindrical body 214 extending toward the front side of cathode 201.
When the plasma generated between cathode 201 and electrode cylindrical body 214 of anode 203 is released further forward than cathode 201 and diffused, diffusing material 218, mainly carbon (C) particles among the vacuum arc plasma constituent particles, recrystallizes on the inner wall of electrode cylindrical body 214 mainly, to adhere and deposit. In particular, when the recrystallization proceeds on the surface of a protruding portion 216, the deposited matter detaches in a flake-like configuration, and falls toward the cathode 201 side. However, because protruding portions 216 have a ring-like configuration, a problem occurs as shown in
The object of the present invention, in the view of the above problem, is to provide a multiply divided anode wall type plasma generation apparatus that can prevent a short-circuit between cathode and anode by a detached deposited matter that had adhered and deposited on the anode inner wall from the diffusion plasma, and a plasma processing apparatus that uses this.
The present inventors, as a result of having studied intensively to solve the short-circuit problem that occurs through the detachment phenomenon of large carbon flakes from ringed protruding portions, have succeeded in a size reduction of carbon flakes by a multiple division of the anode inner wall, and have thus solved the problem.
The first form of the present invention is, in a plasma generation apparatus in which a supply source of a plasma constituent is made to be a cathode, a cylinder-shaped anode is installed at a front direction or a periphery of said cathode, a vacuum arc discharge is done between said cathode and said anode under a vacuum environment, and plasma is generated from said cathode surface, a plasma generation apparatus, characterized in that a large number of recesses and protrusions is built on a cylinder inner wall that comprises said anode, so that when a part of said plasma ejected from said cathode to a direction of said anode adheres and deposits to said recesses and protrusions, said deposited matter detaches from said anode as a minute fragment.
The second form of the present invention is the plasma generation apparatus of the first form, wherein the longest length of a protruding portion of said recesses and protrusions is made shorter than the width of a gap between said cylinder inner wall and an outer circumference of said cathode.
The third form of the present invention is the plasma generation apparatus of the first or second form, wherein a large number of said recesses and protrusions is formed from any one of lattice-like, diagonally crossing, and island-like patterns.
The fourth form of the present invention is the plasma generation apparatus of the first, second, or third form, wherein within said cylinder inner wall comprising said anode, the area near said cathode is made to be a formation area of said pattern for said recesses and protrusions, and an annular groove pattern, in which a multiple annular grooves are engraved in a front direction of said cathode, is formed on a remaining area of said cylinder inner wall.
The fifth form of the present invention is the plasma generation apparatus of any one of the first to fourth forms, wherein an annular recess position is formed at a periphery of said cathode, so that said minute piece detached from said anode is retained and collected in said annular recess position.
The sixth form of the present invention is the plasma generation apparatus of any one of the first to fifth forms, wherein a retention portion for said minute piece is installed beneath said cathode, and at the same time, an exposing portion that communicates with said retention portion is formed at a periphery of said cathode, so that said minute piece detached from said anode is retained and collected in said retention portion through said exposing portion.
The seventh form of the present invention is a plasma processing apparatus, characterized in that it includes the plasma generation apparatus concerning any one of the first to sixth forms, a plasma transport tube that transports said plasma generated by said plasma generating apparatus, and a plasma processing portion that processes an object to be treated by said plasma supplied from said plasma transport tube.
The eighth form of the present invention is the plasma processing apparatus of the seventh form, wherein a starting end side insulator is interposed between a plasma outlet in a cylindrical body of said anode and said plasma transport tube, a finishing end side insulator is interposed between said plasma transport tube and said plasma processing portion, and said plasma generating portion, said plasma transport tube, and said plasma processing portion are mutually separated electrically so that an electric influence from said plasma generating portion and said plasma processing portion on said plasma transport tube is blocked.
The ninth form of the present invention is the plasma processing apparatus of the seventh or eighth form, wherein said plasma transport tube comprises a plasma straightly advancing tube connected to said plasma generating portion, a first plasma advancing tube connected in a bent manner to said plasma straightly advancing tube, a second plasma advancing tube diagonally arranged and connected at a finishing end of said first plasma advancing tube in a bent manner with predetermined bending angle with respect to a tube axis of said first plasma advancing tube, a third plasma advancing tube connected in a bent manner to a finishing end of said second plasma advancing tube so that said plasma is exhausted from a plasma outlet, and total length L for said plasma to arrive from said target surface to said object to be treated is set to satisfy 900 mm≦L≦1350 mm.
The tenth form of the present invention is the plasma processing apparatus of the seventh, eighth, or ninth form, wherein said second plasma advancing tube is placed geometrically at a position off a straight line of sight from a plasma outlet of said third plasma advancing tube to a plasma outlet side of said first plasma advancing tube.
The eleventh form of the present invention is the plasma processing apparatus of the ninth or tenth form, wherein θ≧θ0 is satisfied when an angle of elevation from a tube cross section top end of the plasma entrance port side of said third plasma advancing tube to a tube cross section bottom end of the plasma outlet side of said first plasma advancing tube is defined as θ, and an angle of elevation from a tube cross section bottom end of the plasma outlet side of said third plasma advancing tube to a tube cross section top end of the plasma outlet side of said second plasma advancing tube is defined as θ0.
The twelfth form of the present invention is the plasma processing apparatus of any one of the eighth to eleventh forms, wherein a magnetic field generating means for plasma transportation that generates a magnetic field for plasma transportation is set up in each of said plasma straightly advancing tube, said first plasma advancing tube, said second plasma advancing tube, and said third plasma advancing tube, a deflection magnetic field generating means for deflecting said magnetic field for plasma transportation is attached in said first plasma advancing tube and/or said second plasma advancing tube, and a plasma stream is deflected toward a tube center side by a deflection magnetic field generated by said deflection magnetic field generating means.
According to the first form of the present invention, a large number of said recesses and protrusions are arranged in the cylinder inner wall forming said anode so that it is multiply divided, and by the deposited matter separation effect of the large number of said recesses and protrusions, even if the diffusion plasma adheres and deposits to said anode, a large or elongated deposited matter do not form, and said deposited matter detaches as a minute piece from said anode. Because of this, said deposited matter do not bridge across said cathode and said anode upon detaching, a generation of short circuit between two electrodes can be prevented, and it contributes to a stable operation and an improvement of the operation efficiency of the plasma generation apparatus.
The placement of the anode in the present invention can be carried out so that it is located forward of the cathode, or in a placement form in which it surrounds a part or the whole of the cathode. Also, the cylindrical body structure of the anode is not limited to a cylindrical form with a uniform inside diameter, but the present invention can be applied with a frusto-conical internal wall structure.
The deposited matter as a carbon flake grows in a way associated with the size of the protruding portion surface of said recesses and protrusions. Therefore, according to the second form of the present invention, because the longest length of the protruding portions of said recesses and protrusions is made shorter than the width of the gap between said cylinder inner wall and the outer circumference of said cathode, a deposited matter larger than said gap does not detach, and a generation of a short circuit between the cathode and the anode can be prevented without causing a bridge formation by said deposited matter.
According to the third form of the present invention, because the large number of said recesses and protrusions is formed from any one of lattice-like, diagonally crossing, and island-like patterns, a multiple division of the cylinder inner wall forming said anode can be realized, the size of said deposited matter is reduced by the deposited matter separation effect of each pattern, and a generation of short circuit between the cathode and the anode can be prevented without causing a bridge formation by said deposited matter.
As for the quantity of deposition by diffusion plasma, it shows a tendency to increase in the periphery of said cathode that is the source of supply of the plasma constituent. Therefore, according to the fourth form of the present invention, by paying attention to this deposition tendency, a size reduction of the deposited matter is realized, by making the area near said cathode, within said cylinder inner wall comprising said anode, to be a formation area of said pattern for said recesses and protrusions. Also, by forming an annular groove pattern, in which a multiple annular grooves are engraved in the front direction of said cathode, on the remaining area of said cylinder inner wall, an area of the anode protruding portions formed by said annular groove pattern is obtained, inducing the generation of a vacuum arc with high efficiency. Because of these, a generation of short circuit between the cathode and the anode is prevented, and at the same time, an improvement of the plasma generation efficiency can be done.
According to the fifth form of the present invention, because an annular recess position is formed at a periphery of said cathode so that said minute piece detached from said anode is retained and collected in said annular recess position, said minute piece fallen around said cathode periphery does not deposit and come into contact with said cathode, and a generation of short circuit between the cathode and the anode can be prevented beforehand reliably.
According to the sixth form of the present invention, a retention portion for said minute piece is installed beneath said cathode, and at the same time, an exposing portion that communicates with said retention portion is formed at a periphery of said cathode, so that said minute piece detached from said anode is retained and collected in said retention portion through said exposing portion. Because of this, said minute piece that have detached and fell in said cathode periphery does not deposit at all, and a generation of short circuit between the cathode and the anode can be prevented even more reliably.
According to the seventh form of the present invention, when the plasma generated by the plasma generation apparatus of any one of said first to sixth forms is transported through said plasma transport tube and supplied to said plasma processing portion so that a film formation processing, for example, is done, a stable operation of said plasma generation apparatus can be done without producing a short circuit between the cathode and the anode, and an improvement of the process efficiency of film formation can be carried out.
In plasma treatment, high purity plasma is used for doing film formation among others, and there is a need to carry out an improvement of the surface treatment precision. Among the factors that obstruct a generation of high purity plasma, there is one caused by droplets generated from the target (cathode) mixing with the plasma. Among this type of droplets, there exist electrically charged droplets bearing positive and/or negative charge (positive droplets and negative droplets) and neutral droplets that do not bear a charge.
A plasma processing apparatus concerning the present invention has a plasma generation apparatus comprising an anode on which a large number of said recesses and protrusions have been formed, and the operation efficiency can be improved by preventing a detachment of a large carbon flake without decreasing the plasma generation efficiency. Moreover, a high purification of the generated plasma can be realized by applying removal measures for neutral and electrically charged droplets using the eighth to twelfth forms.
According to the eighth form of the present invention, by interposing a starting end side insulator between said plasma generating portion and said plasma transport tube, and interposing a finishing end side insulator between said plasma transport tube and said plasma processing portion, a complete electrical independence is achieved by said plasma generating portion, said plasma transport tube, and said plasma processing portion. As a result, an electric influence from said plasma generating portion and said plasma processing portion toward the plasma transport tube is completely blocked, the plasma transport tube that is usually formed from a metal becomes constant in terms of the electric potential as a whole, and an electric potential difference does not exist in the plasma transport tube. Because there is no electric potential difference, an electrical force, based on electric potential difference, toward charged particles is not generated. Because electrically charged droplets are one type of charged particles, an electrical force does not act on electrically charged droplets in a plasma transport tube in a constant electric potential state, and therefore electrically charged droplets can be handled in the same manner as neutral droplets. Therefore, by means of the geometric removal method of neutral droplets described below, it becomes possible for electrically charged droplets to be removed together with neutral droplets while advancing through the plasma transport tube. Because of this, the plasma supplied from the plasma transport tube becomes a high purity plasma from which neutral droplets and electrically charged droplets have been removed by the neutral droplet removal structure, and by this high purity plasma, a high purity plasma treatment is made possible toward an object to be treated in the plasma processing portion.
According to the ninth form of the present invention, the plasma generating apparatus is offered in which said plasma transport tube is composed in a bent manner in three stages of a plasma straightly advancing tube connected to said plasma generating portion, a first plasma advancing tube connected in a bent manner to said plasma straightly advancing tube, a second plasma advancing tube diagonally arranged and connected at the finishing end of said first plasma advancing tube in a bent manner with a predetermined bending angle with respect to the tube axis of said first plasma advancing tube, and a third plasma advancing tube connected in a bent manner to the finishing end of said second plasma advancing tube so that the plasma is exhausted from a plasma outlet, and total length L from the target surface to the object to be treated is set to satisfy 900 mm≦L≦1350 mm. Furthermore in details, said length L is defined as the total length that is the sum of length L0 from the target surface to the outlet of the plasma straightly advancing tube, length L1 of the first plasma advancing tube, length L2 of the second plasma advancing tube, length L3 of the third plasma advancing tube, together with plasma effective distance L4 that is the distance for the plasma to reach from the plasma outlet of said third plasma advancing tube to the object to be treated. That is to say, L=L0+L1+L2+L3+L4, and the detail is shown in
Said second plasma advancing tube is inclined in said bending angle (angle of inclination), and droplets can be blocked when the angle of inclination is large, but the film formation rate to the surface of the object to be treated decreases because the plasma density decreases. On contrary, when the angle of inclination is small, droplets intrude the treatment chamber, but the film formation rate to the surface of the object to be treated does not decrease because the decrease in the plasma density is small. Therefore, said angle of inclination can be chosen appropriately from the relation between the film formation rate and the tolerance for droplets.
Said bent pathway of three stages in the present invention by said plasma straightly advancing tube, said first plasma advancing tube, said second plasma advancing tube, and said third plasma advancing tube is comprised by connecting each tube on a same plane, or comprised by positioning them in three dimension spatially.
According to the tenth form of the present invention, said second plasma advancing tube is placed geometrically at the position away from the straight line of sight from the plasma outlet of said third plasma advancing tube to the plasma outlet side of said first plasma advancing tube. Because the droplets led out from said first plasma advancing tube are not exhausted directly from the plasma outlet of said third plasma advancing tube, but instead they collide with the pathway inner wall and are adhered and removed in said bent pathway process of three stages, the droplets adhering to the object to be treated can be largely reduced, and a plasma treatment becomes possible by high purity plasma from which droplets have been removed highly efficiently.
The outlet of said third plasma advancing tube may be connected directly to the outer wall surface of the plasma processing portion, or it may be positioned by inserting deeply in the inside of said outer wall surface. Furthermore, while maintaining the positional relationship between the outlet of said third plasma advancing tube and said outer wall surface, a rectifying tube and/or a deflection/oscillation tube could be installed between the second plasma advancing tube and the third plasma advancing tube.
According to the eleventh form of the present invention, θ≧θ0 is satisfied when the angle of elevation from the tube cross section top end of the plasma entrance port side of said third plasma advancing tube to the tube cross section bottom end of the plasma outlet side of said first plasma advancing tube is defined as θ, and the angle of elevation from the tube cross section bottom end of the plasma outlet side of said third plasma advancing tube to the tube cross section top end of the plasma outlet side of said second plasma advancing tube is defined as θ0. Because of this, said second plasma advancing tube can be placed at the position off the straight line of sight from the plasma outlet of said third plasma advancing tube to the plasma outlet side of said first plasma advancing tube. Therefore, for example, in cases where said bent pathway of three stages is comprised by connecting on a same plane, a tube passage configuration can be realized in which droplets led out from said first plasma advancing tube are not directly exhausted by the plasma outlet of said third plasma advancing tube, and a plasma treatment using high purity plasma from which droplets have been removed highly efficiently becomes possible.
As explained above, needless to say, the outlet of said third plasma advancing tube may be connected directly to the outer wall surface of the plasma processing portion, or it may be positioned by inserting deeply in the inside of said outer wall surface. Also, needless to say, a rectifying tube and/or a deflection/oscillation tube could be installed between the second plasma advancing tube and the third plasma advancing tube.
According to the twelfth form of the present invention, the magnetic field generating means for plasma transportation that generates a magnetic field for plasma transportation is set up in each of said plasma straightly advancing tube, said first plasma advancing tube, said second plasma advancing tube, and said third plasma advancing tube, the deflection magnetic field generating means for deflecting said magnetic field for plasma transportation is attached in said first plasma advancing tube and/or said second plasma advancing tube, and the plasma stream is deflected toward the tube center side by the deflection magnetic field generated by said deflection magnetic field generating means. Because of this, the heterogeneity of said magnetic field for plasma transportation at the connecting section of said first plasma advancing tube and/or said second plasma advancing tube, that is to say, the trouble in which the additional magnetic field becomes strong at the inside of the bending portion due to the configuration of said magnetic field coil for magnetic field generation for plasma transportation, is deflected and adjusted by said deflection magnetic field, the plasma stream is guided to the tube passage center, the plasma density is held high, and a plasma treatment using high density, high purity plasma becomes possible.
1 Plasma generation apparatus
2 Cathode
3 Anode
4 Plasma generating portion
5 Trigger electrode
6 Plasma advancing path
7 Bending portion
8 Bending magnetic field generator
9 Droplet advancing path
10 Droplet collecting portion
11 Baffle
12 Baffle
13 Radially enlarged tube
14 Magnetic field generator
15 Plasma processing portion
16 Object to be treated
17 Baffle
18 Magnetic field generator
19 Baffle
20 Magnetic field generator
21 Target coil
22 Filter coil
23 Radially reduced tube
24 Rotation shaft
25 Power supply
26 Electricity conduction line
27 Electricity conduction line
28 Anode inner wall
29 Outer wall
30 Insulation member
31 Insulation member
32 Electric discharge surface
33 Tube passage end
34 Gap
35 Protruding portion
36 Retention portion
37 Groove
38 Groove
39 Protruding portion of small fragment
40 Carbon flake
41 Diffusing material
42 Annular recess position
43 Protruding portion
44 Diagonal direction groove
45 Lateral groove
46 Hexagonal protruding portion
47 Honeycomb groove
48 Anode
49 Lattice-like recess-protrusion pattern
50 Annular groove pattern
101 Plasma processing portion
102 Plasma generating portion
103 Plasma straightly advancing tube
104 First plasma advancing tube
105 Second plasma advancing tube
106 Third plasma advancing tube
107 Plasma outlet
108 Arrow
108
a X-direction oscillating magnetic field generator
108
b Y-direction oscillating magnetic field generator
109 Arrow
110 Cathode
111 Trigger electrode
112 Anode
113 Arc power supply
114 Cathode protector
115 Plasma stabilizing magnetic field generator
116 Insulation plate
117 Magnetic field coil
118 Magnetic field coil
119 Magnetic field coil
121 Magnetic field coil
122 Deflection magnetic field generating means
123 Deflection magnetic field generating means
124 Deflection magnetic field generating means
125
a Gas inflow port
125
b Exhaust port
127 Magnetic pole
128 Magnetic pole
129 Movable yoke
130 Deflection magnetic field generating coil
131 Guiding body
132 Guiding groove
133 Pin
134 Fastening nut
135 Slide member
136 Spacer
137 Adjusting portion main body
138 Slide groove
139 Pin
140 Fastening nut
141 Droplet collecting plate (baffle)
142 Droplet collecting plate (baffle)
143 Droplet collecting plate (baffle)
144 Droplet collecting plate (baffle)
160 Droplet collecting plate (part of a baffle)
161 Inner circumferential tube
162 Opening
163 Bias power supply
170 Aperture
171 Opening
172 Stopper
173 Screw
174 Protrusion
175 Tube
176 Engagement recess
177 Arrow
200 Plasma generating portion
201 Cathode
202 Trigger electrode
203 Anode
204 Plasma
205 Power supply
206 Plasma stabilizing magnetic field generator
207 Plasma stabilizing magnetic field generator
208 Plasma processing portion
209 Object to be treated
210 Gas introduction system
211 Gas exhaust system
212 Droplet collecting portion
213 Cathode material particle
214 Electrode cylindrical body
215 Circular groove
216 Protruding portion
217 The upper side
218 Diffusing material
219 Circular arc part
220 Carbon flake
1109 Outlet tube
1100 Plasma straightly advancing tube
1101 First plasma advancing tube
1102 Second plasma advancing tube
1103 Third plasma advancing tube
1104 Connecting port
1105 Plasma outlet
1106 Plasma outlet
1107 Rectifying tube
1108 Frustoconical tube
1110 Plasma outlet
1111 Arrow
1112 Arrow
1113 Magnetic field coil for scanning
1114 Rectifying magnetic field coil
A Plasma generating portion
A1 Plasma generating portion container,
A2 Target exchange portion
B Plasma transport tube
B0 T-shaped transport tube
B2 Second transport tube
B23 Bending transport tube
B3 Third transport tube
C Plasma processing portion
C1 Installation position
C2 Target positon
C3 Processing portion container
CT Connection terminal
E Bias power supply
EA1 Bias power supply for container
EA2 Bias power supply for exchange portion container
EB Bias power supply for transport tube
EB01T Bias power supply for transport tube
EB2 Bias power supply for second transport tube
EB23 Bias power supply for bending transport tube
EB3 Bias power supply for third transport tube
EC Bias power supply for processing portion
EW Bias power supply for object to be treated
FT Floating terminal
GND Ground
GNDT Grounding terminal
IFA Finishing end side insulator
II1 The first middle insulator
ISA Starting end side insulator
IA Inter-container insulator
II2 The second middle insulator
NVT Variable negative electric potential terminal
P0 Plasma straightly advancing tube
P1 First plasma advancing tube
P2 Second plasma advancing tube
P3 Third plasma advancing tube
P4 Radially enlarged tube
PVT Variable positive electric potential terminal
S1 Plasma outlet
S2 Plasma entrance port
S3 Plasma outlet
VT Variable terminal
W Work
In the following, a multiply divided anode wall type plasma generation apparatus and plasma processing apparatus concerning an embodiment of the present invention is explained in detail, based on the attached figures.
The second advancing path comprises radially enlarged tube 13 in which multiple baffles 12 have been installed in the inner wall, and magnetic field generator 20 that generates a plasma advancing magnetic field is set up in radially enlarged tube 13. When plasma P advances through radially enlarged tube 13, the remaining droplets D collide with and adhere to said baffle 12, and thus droplets D are removed furthermore. Radially enlarged tube 13 is inclinedly arranged with respect to said straightly advancing tube passage. The finishing end of radially enlarged tube 13 is connected to plasma processing portion 15 through radially reduced tube 23. Plasma P from which droplets D have been removed is supplied to plasma processing portion 15 by the magnetic field of magnetic field generator 14, 14, and it can plasma-treat object to be treated 16. Baffle 19 is also set up in radially reduced tube 23.
By separating the striker in the contact position as shown in solid line toward the separation direction, a vacuum arc discharge is induced between electric discharge surface 32 of cathode 2 and anode inner wall 28. The striker swings after receiving a rotational drive force from a rotational drive source (not shown). When the striker in the separated position is put into contact with electric discharge surface 32, the torque reaction force of the striker that has come in contact by the rotational drive source is detected, and the contact condition is confirmed. Furthermore, filter coil 22 is arranged at the plasma outlet side of plasma generating portion 4, and plasma advancing magnetic field 132 is formed. Stabilizing magnetic field B1 generated by target coil 21 is formed in reversed-phase (cusp) in comparison with plasma advancing magnetic field 132, so that a generation of stable plasma becomes possible. As shown in (2B) of
In the inner wall of electrode cylindrical body of anode 3, recesses and protrusions are engraved in shape of a matrix by longitudinal and lateral grooves 37, 38, and thus many protruding portions 35 are formed. Protruding portions 35 have a thin rectangular box-like configuration that is curved. Beneath gap 34 set up at the lower part of the electrode cylindrical body, retention portion 36 larger that the diameter of the cylinder is placed for collecting carbon flakes.
As shown in
A multiply divided pattern in the anode electrode cylindrical body is not limited to a lattice-like matrix pattern. For example, it can be a diagonally crossing pattern shown in (5B) of
Because carbon flakes merely detach by use of a multiply divided anode concerning the present embodiment, annular recess position 42 surrounding cathode 2 in the lower part of gap 34 may be set up instead of retention portion 36, as shown by broken lines of
Deposited mass on an anode inner wall by diffusion plasma tends to increase nearby cathode 2 that is the supply source of the plasma constituent material. Therefore, it is not always necessary to make multiple divisions on the entire surface of the anode inner wall, but it is sufficient to make multiple divisions in either the entirety or a part of the inner wall, according to the size of the anode area or the anode cylindrical body.
In a plasma processing apparatus concerning the present embodiment, plasma generation apparatus 1 comprising a multiply divided anode is provided, and an improvement of the operation efficiency is done by preventing a detachment of a large carbon flake without decreasing the plasma generation efficiency. Furthermore, it comprises a plasma high-purification configuration, in which neutral droplets and electrically charged droplets can be removed with higher efficiency. In the following, the plasma high-purification configuration in a plasma processing apparatus of the present embodiment is explained. In
It is composed of plasma generating portion A that generates the plasma supplied to plasma processing portion C (a chamber), and plasma transport tube B. Plasma generating portion A corresponds to plasma generating portion 4. In plasma processing portion C, work (object to be treated by plasma) W is set up, a reactive gas is introduced as necessary by a gas introduction system connected into the chamber from gas inflow port G1, and reactant gas and plasma stream are exhausted from exhaust port G2 by a gas exhaust system. Plasma generating portion A has a cathode (target) that generates plasma by vacuum arc discharge under a vacuum environment. Plasma transport path B comprises a tube passage that mobilizes plasma, and plasma transport path B also has a structure of a droplet removing portion that removes droplets produced as a byproduct from the cathode by its geometrical structure. This plasma transport path B is also a plasma stream distribution tube passage, and comprises plasma straightly advancing tube P0 connected to plasma generating portion A, first plasma advancing tube P1 connected in a bent manner to plasma straightly advancing tube P0, second plasma advancing tube P2 inclinedly arranged and connected at the finishing end of first plasma advancing tube P1 in a predetermined bending angle with respect to the tube axis, and third plasma advancing tube P3 connected in a bent manner at the finishing end of second plasma advancing tube P2 so that plasma is exhausted from the plasma outlet. Second plasma advancing tube P2 corresponds to said second advancing path of
Plasma straightly advancing tube P0 adheres and removes droplets advancing straightly from plasma generating portion A by colliding them against finishing end section E opposite plasma generating portion A, or against the tube inner wall. The plasma advancing length from said target position C2 of plasma generating portion A to the outlet of plasma straightly advancing tube P0, that is to say, the connection point between plasma straightly advancing tube P0 and first plasma advancing tube P1, is defined as L0. First plasma advancing tube P1 communicates and connects toward the perpendicular direction at the side wall of the finishing end side of plasma straightly advancing tube P0. The plasma advancing length of first plasma advancing tube P1 is defined as L1. Second plasma advancing tube P2 is inclinedly arranged between first plasma advancing tube P1 and third plasma advancing tube P3, and its plasma advancing length is defined as L2. Third plasma advancing tube P3 is placed toward a parallel direction with respect to first plasma advancing tube P1, and its plasma advancing length is defined as L3. The plasma outlet of third plasma advancing tube P3 is extended inside the plasma processing portion C. The plasma effective distance in which the plasma exhausted from the plasma outlet of third plasma advancing tube P3 arrives at installation position C1 of the object to be treated in plasma processing portion C is defined as L4. A plasma advancing path formed in a bent manner in three stages is formed by plasma straightly advancing tube P0, first plasma advancing tube P1, second plasma advancing tube P2, and third plasma advancing tube P3.
Around the outer circumference of each plasma advancing tube, a magnetic field coil (not shown) for generating a magnetic field for plasma transportation is wound with a purpose to transport plasma stream along the tube passage. By magnetic field generating means for plasma transportation comprising of magnetic field coil, a magnetic field for plasma transportation is generated in the whole three stages of said bent pathway, and the plasma transport efficiency is improved. Also, a baffle (not shown) for droplet removal is set up in the tube inner wall.
In the plasma advancing path concerning the above configuration, total length (plasma transport distance) L(=L0+L1+L2+L3+L4), which is the sum of plasma advancing lengths L0-L3 respectively of the interval from the target surface to the outlet of plasma straightly advancing tube P0, first plasma advancing tube P1, second plasma advancing tube P2, and third plasma advancing tube P3, together with plasma effective distance L4, is set to satisfy 900 mm≦L≦1350 mm.
According to the present embodiment, the plasma transport distance in the above plasma advancing path is shortened further than a conventional T-shaped plasma advancing path (A1 of
In the present embodiment, the plasma advancing path consists of said bent pathway of three stages, and furthermore, by the tube passage placement shown in
Second plasma advancing tube P2 is placed geometrically at a position off the straight line of sight from plasma outlet S3 of third plasma advancing tube P3 to the plasma outlet S1 side of first plasma advancing tube P1. That is to say, when the angle of elevation from the tube cross section top end of the plasma entrance port S2 side of third plasma advancing tube P3 to the tube cross section bottom end of the plasma outlet S1 side of first plasma advancing tube P1 is defined as θ, and when the angle of elevation from the tube cross section bottom end of the plasma outlet S3 side of third plasma advancing tube P3 to the tube cross section top end of the plasma outlet S2 side of second plasma advancing tube P2 is defined as θ0, θ≧θ0 is satisfied.
By the above geometric tube passage placement, straightly advancing droplets led out from first plasma advancing tube P1 are prevented from directly intruding third plasma advancing tube P3, so that they cannot be exhausted from plasma outlet S3 of third plasma advancing tube P3. Therefore, it becomes possible to adhere and remove the droplets by collision at the pathway inner wall during said bent pathway process of three stages, the adhesion mass of the droplets on the object to be treated can be reduced greatly as described above, and a plasma treatment by high purity plasma from which droplets have been removed with high efficiency can be done.
In the present embodiment, said bent pathway of three stages is connected and composed on a same plane, but even when the tube pathway is composed in a spatially bent manner in three stages, by the same geometric arrangement as above, a tube pathway arrangement can be realized in which the straightly advancing plasma is not exhausted directly from the plasma outlet of the third plasma advancing tube.
As shown by the broken lines, second plasma advancing tube P2 may be built as radially enlarged tube P4 whose inner diameter is greater than first plasma advancing tube P1 and third plasma advancing tube P3. That is to say, second plasma advancing tube P2 is set up as radially enlarged tube P4, first plasma advancing tube P1 is set up as an introduction side radially reduced tube connected to the plasma introduction side starting end of radially enlarged tube P4, and third plasma advancing tube P3 is set up as a discharge side radially reduced tube connected to the plasma discharge side finishing end of radially enlarged tube P4. If radially enlarged tube P4 is positioned midway, the plasma stream introduced from the introduction side radially reduced tube into the radially enlarged tube is diffused by the diameter-increasing effect of the plasma advancing path by radially enlarged tube P4. By the diffusion of this plasma stream, the droplets mixed with the plasma diffuse inside the radially enlarged tube P4, and are collided with, adhered to, and collected at the inner side wall of radially enlarged tube P4. Also, when the plasma stream in radially enlarged tube P4 is exhausted, the droplets scattered in the radially enlarged tube inner wall surface side are collided with, adhere to, and collected by the step portion by the diameter-narrowing effect from radially enlarged tube P4 to discharge side radially reduced tube, and thereby the droplets are not rejoined with the plasma stream, and a re-mixture of droplets can be prevented. Therefore, the droplets can be adhered to the internal side wall of radially enlarged tube P4, and thus can be collected sufficiently. Because of this, the droplets can be removed efficiently inside the tube path of first plasma advancing tube P1, second plasma advancing tube P2, and third plasma advancing tube P3. Also, when the central axes of radially enlarged tube P4 and the introduction side radially reduced tube and/or the discharge side radially reduced tube are set off instead of being lined up, the droplets become easy to separate from the plasma stream, and the capture effect of droplets increases even more. Moreover, just by forming radially enlarged tube P4 in the plasma advancing path, a droplet removing portion can be constituted easily and cheaply.
Said bent structure in three stages and angle relation θ≧θ0 are mainly for providing the geometric structure of plasma transport path B installed in order to remove droplets advancing straightly, such as neutral droplets. Because electrically charged droplets are influenced by the electric effect and magnetic action from the environment, they may deviate from straight advancement in an electromagnetic field because of the electric field and/or the magnetic field. Therefore, in order to remove the electrically charged droplets, it is necessary to equip with a mechanism to intentionally remove in particular the electric potential difference from the plasma transport path. Because a magnetic field for plasma transport is necessary by all means, it is difficult to remove a magnetic field in a plasma device. Because the electric force towards the electrically charged droplets can be erased when the electric potential difference is removed, in this case the electrically charged droplets have a property of advancing straightly in the same manner as neutral droplets, and it becomes possible to remove the electrically charged droplets too by the previously described geometrical structure.
The plasma processing apparatus of present embodiment has a structure for removal of electrically charged droplets. Plasma generating portion A and plasma transport tube B are mutually insulated electrically by starting end side insulator IS, and moreover, plasma transport tube B and plasma processing portion C are mutually insulated electrically by finishing end side insulator IF. As a result, plasma transport tube B does not receive an electric influence from plasma generating portion A and plasma processing portion C at all, and plasma transport tube B is set so that the electric potential is constant throughout. As mentioned above, plasma transport tube B comprises plasma straightly advancing tube P0, first plasma advancing tube P1, second plasma advancing tube P2, and third plasma advancing tube P3, and because the electric potential becomes constant throughout the tube arrangement, no electric potential difference exists at all inside plasma transport tube B, and the electrically charged droplets do not receive at all an electric force from an electric potential difference inside plasma transport tube B. Therefore, electrically charged droplets too are removed inside plasma transport tube by the previously described structures in three stages and the angle relation θ≧θ0, in the same manner as neutral droplets.
Also, a bias power supply can be additionally installed in each component of present plasma processing apparatus. In
Each bias power supply EA1, EB, EC, and EW has a same structure, and this structure is explained by using
Bias power supply EA2 for exchange portion container is grounded at GND, and it is designed for safety even in a case of contact by a worker. Bias power supply EA1 for the container of plasma generating portion A is set to an electric floating state, so that the electric effect toward the plasma is erased, and a stable plasma generation is promoted. Bias power supply for T-shaped transport tube is connected to variable negative voltage terminal NVT of
In
As explained above, the variable positive electric potential of each bias power supply EW, EC, EB3, EB2, EA1, EA2, and EB01 can be adjusted within a range of 0 to +50V, and the variable negative electric potential is adjusted within a range of 0 to −50V. The electric potential of each bias power supply is varied and adjusted so that the droplet removal efficiency of the apparatus as whole is maximized within these electric potential ranges.
Next, an installation example of magnetic field coils that are suitable for a plasma processing apparatus in the present invention is explained, as well as an installation example of baffles (collecting plates) for droplet removal.
Plasma processing apparatus of
The plasma transport tube comprising plasma straightly advancing tube 103, first plasma advancing tube 104, second plasma advancing tube 105, and third plasma advancing tube 106 is formed in a bent manner in three stages, just like the plasma transport tube of FIG, 8. Plasma outlet 107 of third plasma advancing tube 106 is connected to plasma introduction port of plasma processing portion 101. Also, second plasma advancing tube 105 is placed geometrically at a position off the line of sight from plasma outlet 107 of third plasma advancing tube 106 to the plasma outlet side of first plasma advancing tube 104, in the same manner as
Plasma generating portion 102 comprises cathode (cathode) 110, trigger electrode 111, inner wall multiply divided anode (anode) 112, arc power supply 113, cathode protector 114, and plasma stabilizing magnetic field generator (an electromagnetic coil or a magnet) 115. Cathode 110 is the supply source of the plasma constituent, and its formation material is not limited particularly as long as it is a solid having electroconductivity. A simple metal, an alloy, a simple inorganic substance, an inorganic compound (metallic oxide/nitride) and such can be used individually or as a mixture of two or more substances. Cathode protector 114 electrically insulates parts other than evaporating cathode surface, and prevents a backward diffusion of plasma generated between cathode 110 and anode 112. The formation material of anode 112 is not limited particularly, as long as it does not evaporate at the plasma temperature, and it is a nonmagnetic material that is a solid having electroconductivity. Also the configuration of anode 112 is not limited particularly, as long as it does not obstruct an advancing of arc plasma as a whole. Furthermore, plasma stabilizing magnetic field generator 115 is placed around the circumference of plasma generating portion 102, and it stabilizes the plasma. When arc stabilization magnetic field generator 115 is placed so that the applied magnetic field on the plasma is in mutually reverse direction (cusp form), the plasma is stabilized further. Also, when arc stabilization magnetic field generator 115 is placed so that the applied magnetic field on the plasma is in mutually same direction (mirror form), the deposition rate by the plasma can be improved. Furthermore, plasma generating portion 102 and each plasma tube path are electrically insulated by plasma generating portion side insulation plate 116, and the construction is such that, even if a high voltage is applied to plasma generating portion 102, the portions at forward of plasma straightly advancing tube 103 is in an electrically floating state, so that plasma does not receive an electrical influence inside the plasma advancing path. Also, a processing component side insulation plate (finishing end side insulator IF) is placed between third plasma advancing tube 106 and plasma processing portion 101, the whole of the duct portion for plasma transportation from plasma straightly advancing tube 103 to third plasma advancing tube 106 is set to an electrically floating state, and constructed so that the transported plasma is not influenced by an external power supply (high voltage source and/or GND).
In plasma generating portion 102, an electric spark is triggered between cathode 110 and trigger electrode 111, a vacuum arc is generated between cathode 110 and anode 112, and plasma is generated. Constituent particles of this plasma includes vaporized material from cathode 110, and charged particles originating from the vaporized material and the reactant gas (ion, electron), together with molecules in pre-plasma state, and neutral particles such as atoms. Also, at the same time that plasma constituent particles are ejected, droplets with size from less than submicron to several hundred micron (0.01-1000 μm) are ejected. These droplets form a mixed state with plasma stream 126, and move inside the plasma advancing path as droplet mixture plasma.
At the plasma transport tube comprising plasma straightly advancing tube 103, first plasma advancing tube 104, second plasma advancing tube 105, and third plasma advancing tube 106, a magnetic field generating means for plasma transportation comprising magnetic field coils 117, 118, 119, 120 wound around each tube circumference is installed. The plasma transport efficiency can be improved by generating a magnetic field for plasma transportation throughout the entire three stages of said bent pathway.
Because the plasma advancing path is formed in a bent manner in three stages, magnetic field coil 121 generating a bending magnetic field and deflection magnetic field generating means 123 are installed at the tube connecting portion of first plasma advancing tube 104 and second plasma advancing tube 105, and they bend and guide the plasma stream by the bending magnetic field. Because a coil for bending magnetic field cannot be wound evenly at the connecting section of first plasma advancing tube 104 and second plasma advancing tube 105, heterogeneity of the magnetic field is produced in which the bending magnetic field becomes strong inward of the bending portion. To eliminate this uneven magnetic field, deflection magnetic field generating means 122, 124 are provided by first plasma advancing tube 104 and second plasma advancing tube 105.
Deflection magnetic field generating means 122, 124 consist of deflection magnetic field generating coil 130 and movable yoke 129.
Deflection magnetic field generating means 122, 124 include an adjustment mechanism, in which movable yoke 129 is adjusted by sliding along the tube axis direction, rotating along the circumferential direction, and swinging toward the tube axis direction.
Because deflection magnetic field generating means 122, 124 make possible to adjust movable yoke 129 in a sliding manner in the tube axis direction, a rotating manner in the circumferential direction, and a swinging manner in the tube axis direction, a removal of the heterogeneity of the magnetic field for plasma transportation can be carried out by a fine adjustment by said deflection magnetic field through adjusting the position or the angle of movable yoke 129, and an optimum plasma advancing path comprising a geometrical arrangement of said bent pathway in three stages can be realized.
(15A) of
In the present embodiment, magnetic field coil 119 wound around the outer tube circumference of second plasma advancing tube 105 comprises a magnetic field coil wound elliptically along the inclination axis outside its outer tube circumference. (15B) of
To the plasma transport tube comprising plasma straightly advancing tube 103, first plasma advancing tube 104, second plasma advancing tube 105, and third plasma advancing tube 106, droplet collecting plates (baffles) 141, 142, 143, 144 are implanted on each respective tube inner wall surface. Structure of each collecting plate is explained in detail in the following.
The droplet adhesion surface area of inner circumferential tube 161 is increased by multiple droplet collecting plates 160, and the scattered droplets can be adhered and collected in large quantities reliably. Because, in a plasma transport tube, the installation number of droplet collecting plates 160 is restricted by the limit of the tube length of inner circumferential tube 161, in order to increase the droplet removal area, it is preferable to do a rough surface processing on the surface of droplet collecting plates 160, and thus form rough surfaces having innumerable unevenness. That is to say, by roughening the surface of droplet collecting plates 160, the capture area of droplet collecting plates 160 is increased, and the collection efficiency can be improved. Also, the droplets collided in the recesses are adhered reliably in the recesses, and the droplet collection efficiency increases markedly. Linear pattern processing and pearskin processing can be used for the surface-roughening processing. For a linear pattern processing method, for example, a polishing treatment with an abrasive paper is used. For example, in a pearskin processing method, a blast treatment by alumina, shots, grids, glass beads and such is used. Especially, a microblast processing, in which particles of a few microns are accelerated and nozzle-sprayed, can apply a minute unevening processing on the small surfaces of droplet collecting plates 160.
The implanting area of droplet collecting plates 160 is preferably greater than or equal to 70% of the tube inner wall surface area. In the case of
Droplet collecting plates 160 are shielded electrically from the tube wall of each plasma advancing tube. To inner circumferential tube 161, inner circumferential tube bias power supply 163 is connected as bias voltage application means, and inner circumferential tube 161 can be set to positive electric potential, set to negative electric potential, or grounded to CND. In a case where the bias electric potential of inner circumferential tube 161 is a positive electric potential, it has an effect of pushing the positive ions of the plasma in the transportation direction, and in a case of a negative electric potential, it has an effect of pushing the electrons of the plasma in the transportation direction. The choice of either the positive or the negative is chosen toward the way in which the plasma transportation efficiency is not decreased, and it is decided from the state of the plasma. The electric potential strength is variable too, and it is usually chosen to set inner circumferential tube 161 to +15V from the standpoint of the transportation efficiency. By applying a bias voltage to each droplet collecting plate, its bias electric potential is adjusted, and attenuation of the plasma can be thus suppressed, thereby increasing the plasma transportation efficiency.
In second plasma advancing tube 105, one or more apertures 170 movable along the tube axis direction may be arranged. Said aperture 170 has a structure in which the installation position can be varied along the tube axis direction in second plasma advancing tube 105. A structure that can be moved both forward and backward is acceptable, and a structure that can be moved in only one direction is also acceptable. Because it is movable, the installation position of the aperture can be adjusted, and it also can be removed and washed. This aperture 170 has an opening of a predetermined area at the center, and the droplets are collided and captured on the peripheral wall surface of this opening, while the plasma passing through said opening advances. Said opening may be set up at the center, or it may be set up at an eccentric position. It can be designed in various manners. Therefore, if multiple apertures 170 are installed movably in second plasma advancing tube 105, the removal efficiency of the droplets increases, and the plasma purity can be improved. In the following, an aperture movable in one direction and using flat springs is shown.
(17A) of
Because aperture 170 has a structure in which it is movable to an arbitrary set position inside second plasma advancing tube 105, droplets can be collected by the decrease in the diameter of second plasma advancing tube 105 by aperture 170, and moreover, the set location can be changed appropriately so that the quantity of collection can be adjusted optimally, which contributes to an improvement in the droplet removal efficiency. The set number of apertures 170 is 1, 2 or more. In addition, opening 171 can be set up not only in the center of aperture 170, but it is possible to place it eccentrically in order to add a function to make the plasma flow inside the tube meander.
A ring shaped aperture may be arranged in a connecting section in the plasma advancing path comprising plasma straightly advancing tube 103, first plasma advancing tube 104, second plasma advancing tube 105, and third plasma advancing tube 106. In the same manner as aperture 170, by arranging this aperture for connecting section, the droplets included in the plasma stream can be collected in greater quantity, and the droplet removal efficiency can be improved, by reducing, making eccentric, or both reducing and making eccentric the tube diameter of the plasma advancing path.
In the plasma generating apparatuses of
The plasma transport tube comprising plasma straightly advancing tube 1100, first plasma advancing tube 1101, second plasma advancing tube 1102, and third plasma advancing tube 1103 is formed in a bent manner in three stages, in the same manner as the plasma advancing paths of
In the connecting section with third plasma advancing tube 1103 of the finishing end of second plasma advancing tube 1102 which has been inclinedly arranged, to prevent a decrease in the plasma progress efficiency to the third plasma advancing tube 1103 side through meandering and diffusion of the plasma flow, rectifying magnetic field coil 1114 is installed in rectifying tube 1107 connecting with second plasma advancing tube, so that a rectification magnetic field that rectifies while forcibly converging the plasma flow supplied from second plasma advancing tube 1102 to rectifying tube is generated in the tube. By this rectification magnetic field, the plasma flowing to second plasma advancing tube 1102 can be drawn in a converged manner at the third plasma advancing tube 1103 side, and a generation of plasma with high density and high purity becomes possible.
The relations of X-direction oscillating magnetic field BX(t) at time t by X-direction oscillating magnetic field generators 108a, 108a, Y-direction oscillating magnetic field BY(t) at time t by Y-direction oscillating magnetic field generators 108b, 108b, and scanning magnetic field BR(t) at time t are shown. Scanning magnetic field BR(t) is a synthetic magnetic field of X-direction oscillating magnetic field BX(t) and Y-direction oscillating magnetic field BY(t). To explain in detail, while the plasma stream is oscillated left-right by the X-direction oscillating magnetic field, the plasma stream is scanned up-down by Y-direction oscillating magnetic field, and by repeating this, a large-area plasma exposure to plasma processing portion 1 is made possible. When the cross section area of the plasma stream is smaller than the cross section area of the object to be treated placed inside plasma treatment chamber 1, the plasma stream is scanned top-bottom and left-right, so that a plasma exposure is made possible on the entire surface of the object to be treated. A similar principle is used as, for example, when the electron beam of a CRT display oscillates left-right while moving up-down, and by repeating this movement, the entire surface of the display screen is made to emit light. In
The present invention is not limited to the embodiments described above. Various modifications, design alterations, and others that do not involve a departure from the technical concept of the present invention are also included in the technical scope of the present invention.
According to the present invention, a multiply divided anode wall type plasma generation apparatus can be provided that can improve the operation efficiency without decreasing the plasma generation efficiency by preventing an exfoliation of a large carbon flake. Also, according to a plasma processing apparatus concerning the present invention, an improvement of the operation efficiency is done by having installed a multiply divided anode wall type plasma generation apparatus, and at the same time, a high purification of the generated plasma can be realized by carrying out an elimination measure of neutral droplets and electrically charged droplets. Because of this, it becomes possible to form in the plasma a highly pure thin film whose defects and impurities on the surface of the solid material are markedly few, and to reform uniformly the surface characteristics of a solid without adding defects and impurities by irradiating the plasma, and a plasma processing apparatus can be provided for forming, for example, an abrasion- and corrosion-resistant reinforced film, a protective film, an optical thin film, and a transparent electroconductive film among others in high quality and precision.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2009-157158 | Jul 2009 | JP | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/JP2010/057770 | 5/6/2010 | WO | 00 | 10/19/2011 |
