Plasma processing apparatus

Description

TECHNICAL FIELD

The present invention relates to a plasma processing apparatus.

BACKGROUND ART

There is provided a plasma processing apparatus that generates plasma by applying a high frequency between two electrodes and processes a substrate by the plasma. Such plasma processing apparatus can operate as an etching apparatus or a sputtering apparatus by the bias and/or the area ratio of the two electrodes. The plasma processing apparatus configured as a sputtering apparatus includes the first electrode that holds a target and the second electrode that holds a substrate. A high frequency is applied between the first and second electrodes, and plasma is generated between the first and second electrodes (between the target and the substrate). When plasma is generated, a self-bias voltage is generated on the surface of the target. This causes ions to collide against the target, and the particles of a material constituting the target are discharged from the target.

PTL 1 describes a sputtering apparatus including a grounded chamber, a target electrode connected to an RF source via impedance matching circuitry, and a substrate holding electrode grounded via a substrate electrode tuning circuit.

In the sputtering apparatus described in PTL 1, the chamber can function as an anode in addition to the substrate holding electrode. The self-bias voltage can depend on the state of a portion that can function as a cathode and the state of a portion that can function as an anode. Therefore, if the chamber functions as an anode in addition to the substrate holding electrode, the self-bias voltage can change depending on the state of a portion of the chamber that functions as an anode. The change in self-bias voltage changes a plasma potential, and the change in plasma potential can influence the characteristic of a film to be formed.

If a film is formed on a substrate using the sputtering apparatus, a film can also be formed on the inner surface of the chamber. This may change the state of the portion of the chamber that can function as an anode. Therefore, if the sputtering apparatus is continuously used, the self-bias voltage changes depending on the film formed on the inner surface of the chamber, and the plasma potential can also change. Consequently, if the sputtering apparatus is used for a long period, it is conventionally difficult to keep the characteristic of the film formed on the substrate constant.

Similarly, if the etching apparatus is used for a long period, the self-bias voltage changes depending on the film formed on the inner surface of the chamber, and this may change the plasma potential. Consequently, it is difficult to keep the etching characteristic of the substrate constant.

CITATION LIST
Patent Literature

PTL 1: Japanese Patent Publication No. 55-35465

SUMMARY OF INVENTION
Technical Problem

The present invention has been made based on the above problem recognition, and provides a technique advantageous in stabilizing a plasma potential in long-term use.

According to one aspect of the present invention, there is provided a plasma processing apparatus comprising a balun including a first unbalanced terminal, a second unbalanced terminal, a first balanced terminal, and a second balanced terminal, a grounded vacuum container, a first electrode electrically connected to the first balanced terminal, a second electrode electrically connected to the second balanced terminal, and a ground electrode arranged in the vacuum container and grounded.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a circuit diagram schematically showing the arrangement of a plasma processing apparatus 1 according to the first embodiment of the present invention;

FIG. 2A is a circuit diagram showing an example of the arrangement of a balun;

FIG. 2B is a circuit diagram showing another example of the arrangement of the balun;

FIG. 3 is a circuit diagram for explaining the function of a balun 103;

FIG. 4 is a table exemplifying the relationship among currents I1 (=I2), I2′, and I3, ISO, and α (=X/Rp);

FIG. 5A is a timing chart showing a result of simulating a plasma potential and a cathode potential when 1.5≤X/Rp≤5000 is satisfied;

FIG. 5B is a timing chart showing a result of simulating a plasma potential and a cathode potential when 1.5≤X/Rp≤5000 is satisfied;

FIG. 5C is a timing chart showing a result of simulating a plasma potential and a cathode potential when 1.5≤X/Rp≤5000 is satisfied;

FIG. 5D is a timing chart showing a result of simulating a plasma potential and a cathode potential when 1.5≤X/Rp≤5000 is satisfied;

FIG. 6A is a timing chart showing a result of simulating a plasma potential and a cathode potential when 1.5≤X/Rp≤5000 is not satisfied;

FIG. 6B is a timing chart showing a result of simulating a plasma potential and a cathode potential when 1.5≤X/Rp≤5000 is not satisfied;

FIG. 6C is a timing chart showing a result of simulating a plasma potential and a cathode potential when 1.5≤X/Rp≤5000 is not satisfied;

FIG. 6D is a timing chart showing a result of simulating a plasma potential and a cathode potential when 1.5≤X/Rp≤5000 is not satisfied;

FIG. 7 is a circuit diagram exemplifying a method of confirming Rp−jXp;

FIG. 8 is a circuit diagram schematically showing the arrangement of a plasma processing apparatus 1 according to the second embodiment of the present invention;

FIG. 9 is a circuit diagram schematically showing the arrangement of a plasma processing apparatus 1 according to the third embodiment of the present invention;

FIG. 10 is a circuit diagram schematically showing the arrangement of a plasma processing apparatus 1 according to the fourth embodiment of the present invention;

FIG. 11 is a circuit diagram schematically showing the arrangement of a plasma processing apparatus 1 according to the fifth embodiment of the present invention;

FIG. 12 is a circuit diagram schematically showing the arrangement of a plasma processing apparatus 1 according to the sixth embodiment of the present invention;

FIG. 13 is a circuit diagram schematically showing the arrangement of a plasma processing apparatus 1 according to the seventh embodiment of the present invention;

FIG. 14 is a circuit diagram for explaining the function of a balun according to the sixth embodiment of the present invention;

FIG. 15A is a timing chart showing a result of simulating a plasma potential and two cathode potentials when 1.5≤X/Rp≤5000 is satisfied;

FIG. 15B is a timing chart showing a result of simulating a plasma potential and two cathode potentials when 1.5≤X/Rp≤5000 is satisfied;

FIG. 15C is a timing chart showing a result of simulating a plasma potential and two cathode potentials when 1.5≤X/Rp≤5000 is satisfied;

FIG. 15D is a timing chart showing a result of simulating a plasma potential and two cathode potentials when 1.5≤X/Rp≤5000 is satisfied;

FIG. 16A is a timing chart showing a result of simulating a plasma potential and two cathode potentials when 1.5≤X/Rp≤5000 is not satisfied;

FIG. 16B is a timing chart showing a result of simulating a plasma potential and two cathode potentials when 1.5≤X/Rp≤5000 is not satisfied;

FIG. 16C is a timing chart showing a result of simulating a plasma potential and two cathode potentials when 1.5≤X/Rp≤5000 is not satisfied;

FIG. 16D is a timing chart showing a result of simulating a plasma potential and two cathode potentials when 1.5≤X/Rp≤5000 axis not satisfied; and

FIG. 17 is a circuit diagram schematically showing the arrangement of a plasma processing apparatus 1 according to the eighth embodiment of the present invention;

FIG. 18 is a circuit diagram showing the arrangement of a plasma processing apparatus according to a comparative example;

FIG. 19 is a timing chart showing a simulation result of the operation of the plasma processing apparatus according to the comparative example shown in FIG. 18;

FIG. 20 is a timing chart showing a simulation result of the operation of the plasma processing apparatus according to the comparative example shown in FIG. 18;

FIG. 21 is a timing chart showing a simulation result of the operation of the plasma processing apparatus according to the comparative example shown in FIG. 18; and

FIG. 22 is a circuit diagram schematically showing the arrangement of a plasma processing apparatus 1 according to the ninth embodiment of the present invention.

DESCRIPTION OF EMBODIMENTS

The present invention will be described below with reference to the accompanying drawings by way of exemplary embodiments.

FIG. 1 schematically shows the arrangement of a plasma processing apparatus 1 according to the first embodiment of the present invention. The plasma processing apparatus according to the first embodiment can operate as a sputtering apparatus that forms a film on a substrate 112 by sputtering. The plasma processing apparatus 1 includes a balun (balanced/unbalanced conversion circuit) 103, a vacuum container 110, a first electrode 106, and a second electrode 111. Alternatively, it may be understood that the plasma processing apparatus 1 includes the balun 103 and a main body 10, and the main body 10 includes the vacuum container 110, the first electrode 106, and the second electrode 111. The main body 10 includes a first terminal 251 and a second terminal 252. The first electrode 106 may be arranged to separate a vacuum space and an external space (that is, to form part of a vacuum partition) in cooperation with the vacuum container 110, or may be arranged in the vacuum container 110. The second electrode 111 may be arranged to separate a vacuum space and an external space (that is, to form part of a vacuum partition) in cooperation with the vacuum container 110, or may be arranged in the vacuum container 110.

The balun 103 includes a first unbalanced terminal 201, a second unbalanced terminal 202, a first balanced terminal 211, and a second balanced terminal 212. An unbalanced circuit is connected to the first unbalanced terminal 201 and the second unbalanced terminal 202 of the balun 103, and a balanced circuit is connected to the first balanced terminal 211 and the second balanced terminal 212 of the balun 103. The vacuum container 110 is formed by a conductor, and is grounded.

In the first embodiment, the first electrode 106 serves as a cathode, and holds a target 109. The target 109 can be, for example, an insulator material or a conductor material. Furthermore, in the first embodiment, the second electrode 111 serves as an anode, and holds the substrate 112. The plasma processing apparatus 1 according to the first embodiment can operate as a sputtering apparatus that forms a film on the substrate 112 by sputtering the target 109. The first electrode 106 is electrically connected to the first balanced terminal 211, and the second electrode 111 is electrically connected to the second balanced terminal 212. When the first electrode 106 and the first balanced terminal 211 are electrically connected to each other, this indicates that a current path is formed between the first electrode 106 and the first balanced terminal 211 so that a current flows between the first electrode 106 and the first balanced terminal 211. Similarly, in this specification, when a and b are electrically connected, this indicates that a current path is formed between a and b so that a current flows between a and b.

The above arrangement can be understood as an arrangement in which the first electrode 106 is electrically connected to the first terminal 251, the second electrode 111 is electrically connected to the second terminal 252, the first terminal 251 is electrically connected to the first balanced terminal 211, and the second terminal 252 is electrically connected to the second balanced terminal 212.

In the first embodiment, the first electrode 106 and the first balanced terminal 211 (first terminal 251) are electrically connected via a blocking capacitor 104. The blocking capacitor 104 blocks a DC current between the first balanced terminal 211 and the first electrode 106 (or between the first balanced terminal 211 and the second balanced terminal 212). Instead of providing the blocking capacitor 104, an impedance matching circuit 102 (to be described later) may be configured to block a DC current flowing between the first unbalanced terminal 201 and the second unbalanced terminal 202. The first electrode 106 can be supported by the vacuum container 110 via an insulator 107. The second electrode 111 can be supported by the vacuum container 110 via an insulator 108. Alternatively, the insulator 108 can be arranged between the second electrode 111 and the vacuum container 110.

The plasma processing apparatus 1 can further include a high-frequency power supply 101, and the impedance matching circuit 102 arranged between the high-frequency power supply 101 and the balun 103. The high-frequency power supply 101 supplies a high frequency (high-frequency current, high-frequency voltage, and high-frequency power) between the first unbalanced terminal 201 and the second unbalanced terminal 202 of the balun 103 via the impedance matching circuit 102. In other words, the high-frequency power supply 101 supplies a high frequency (high-frequency current, high-frequency voltage, and high-frequency power) between the first electrode 106 and the second electrode 111 via the impedance matching circuit 102, the balun 103, and the blocking capacitor 104. Alternatively, the high-frequency power supply 101 can be understood to supply a high frequency between the first terminal 251 and the second terminal 252 of the main body 10 via the impedance matching circuit 102 and the balun 103.

A gas (for example, Ar, Kr, or Xe gas) is supplied to the internal space of the vacuum container 110 through a gas supply unit (not shown) provided in the vacuum container 110. In addition, the high-frequency power supply 101 supplies a high frequency between the first electrode 106 and the second electrode 111 via the impedance matching circuit 102, the balun 103, and the blocking capacitor 104. This generates plasma between the first electrode 106 and the second electrode 111, and generates a self-bias voltage on the surface of the target 109 to cause ions in the plasma to collide against the surface of the target 109, thereby discharging, from the target 109, the particles of a material constituting the target 109. Then, the particles form a film on the substrate 112.

FIG. 2A shows an example of the arrangement of the balun 103. The balun 103 shown in FIG. 2A includes a first coil 221 that connects the first unbalanced terminal 201 and the first balanced terminal 211, and a second coil 222 that connects the second unbalanced terminal 202 and the second balanced terminal 212. The first coil 221 and the second coil 222 are coils having the same number of turns, and share an iron core.

FIG. 2B shows another example of the arrangement of the balun 103. The balun 103 shown in FIG. 2B includes a first coil 221 that connects the first unbalanced terminal 201 and the first balanced terminal 211, and a second coil 222 that connects the second unbalanced terminal 202 and the second balanced terminal 212. The first coil 221 and the second coil 222 are coils having the same number of turns, and share an iron core. The balun 103 shown in FIG. 2B further includes a third coil 223 and a fourth coil 224 both of which are connected between the first balanced terminal 211 and the second balanced terminal 212. The third coil 223 and the fourth coil 224 are configured so that the voltage of a connection node 213 of the third coil 223 and the fourth coil 224 is set as the midpoint between the voltage of the first balanced terminal 211 and that of the second balanced terminal 212. The third coil 223 and the fourth coil 224 are coils having the same number of turns, and share an iron core. The connection node 213 may be grounded, may be connected to the vacuum container 110, or may be floated.

The function of the balun 103 will be described with reference to FIG. 3. Let I1 be a current flowing through the first unbalanced terminal 201, I2 be a current flowing through the first balanced terminal 211, I2′ be a current flowing through the second unbalanced terminal 202, and I3 be a current, of the current I2, flowing to ground. When I3=0, that is, no current flows to ground on the balanced circuit side, the isolation performance of the balanced circuit with respect to ground is highest. When I3=I2, that is, all the current I2 flowing through the first balanced terminal 211 flows to ground, the isolation performance of the balanced circuit with respect to ground is lowest. An index ISO representing the degree of the isolation performance is given by an equation below. Under this definition, as the absolute value of the index ISO is larger, the isolation performance is higher.

ISO [dB]=20 log(I3/I2′)

In FIG. 3, Rp−jXp represents an impedance (including the reactance of the blocking capacitor 104) when viewing the side of the first electrode 106 and the second electrode 111 (the side of the main body 10) from the side of the first balanced terminal 211 and the second balanced terminal 212 in a state in which plasma is generated in the internal space of the vacuum container 110. Rp represents a resistance component, and −Xp represents a reactance component. Furthermore, in FIG. 3, X represents the reactance component (inductance component) of the impedance of the first coil 221 of the balun 103. ISO has a correlation with X/Rp.

FIG. 4 exemplifies the relationship among the currents I1 (=I2), I2′, and I3, ISO, and α (=X/Rp). The present inventor found that the arrangement for supplying a high frequency between the first electrode 106 and the second electrode 111 from the first high-frequency power supply 101 via the balun 103, especially satisfying 1.5≤X/Rp≤5000 in this arrangement is advantageous in making the potential (plasma potential) of plasma formed in the internal space (the space between the first electrode 106 and the second electrode 111) of the vacuum container 110 insensitive to the state of the inner surface of the vacuum container 110. When the plasma potential is insensitive to the state of the inner surface of the vacuum container 110, this indicates that it is possible to stabilize the plasma potential even if the plasma processing apparatus 1 is used for a long period. 1.5≤X/Rp≤5000 corresponds to −10.0 dB≥ISO≥−80 dB.

FIGS. 5A to 5D each show a result of simulating the plasma potential and the potential (cathode potential) of the first electrode 106 when 1.5≤X/Rp≤5000 is satisfied. FIG. 5A shows the plasma potential and the cathode potential in a state in which no film is formed on the inner surface of the vacuum container 110. FIG. 5B shows the plasma potential and the cathode potential in a state in which a resistive film (1,000 Ω) is formed on the inner surface of the vacuum container 110. FIG. 5C shows the plasma potential and the cathode potential in a state in which an inductive film (0.6 μH) is formed on the inner surface of the vacuum container 110. FIG. 5D shows the plasma potential and the cathode potential in a state in which a capacitive film (0.1 nF) is formed on the inner surface of the vacuum container 110. With reference to FIGS. 5A to 5D, it is understood that satisfying 1.5≤X/Rp≤5000 is advantageous in stabilizing the plasma potential in various states of the inner surface of the vacuum container 110.

FIGS. 6A to 6D each show a result of simulating the plasma potential and the potential (cathode potential) of the first electrode 106 when 1.5≤X/Rp≤5000 is not satisfied. FIG. 6A shows the plasma potential and the cathode potential in a state in which no film is formed on the inner surface of the vacuum container 110. FIG. 6B shows the plasma potential and the cathode potential in a state in which a resistive film (1,000 Ω) is formed on the inner surface of the vacuum container 110. FIG. 6C shows the plasma potential and the cathode potential in a state in which an inductive film (0.6 μH) is formed on the inner surface of the vacuum container 110. FIG. 6D shows the plasma potential and the cathode potential in a state in which a capacitive film (0.1 nF) is formed on the inner surface of the vacuum container 110. With reference to FIGS. 6A to 6D, it is understood that when 1.5≤X/Rp≤5000 is not satisfied, the plasma potential can change depending on the state of the inner surface of the vacuum container 110.

In both the case in which X/Rp>5000 (for example, X/Rp=∞) is satisfied and the case in which X/Rp<1.5 (for example, X/Rp=1.0 or X/Rp=0.5) is satisfied, the plasma potential readily changes depending on the state of the inner surface of the vacuum container 110. If X/Rp>5000 is satisfied, in a state in which no film is formed on the inner surface of the vacuum container 110, discharge occurs only between the first electrode 106 and the second electrode 111. However, if X/Rp>5000 is satisfied, when a film starts to be formed on the inner surface of the vacuum container 110, the plasma potential sensitively reacts to this, and the results exemplified in FIGS. 6A to 6D are obtained. On the other hand, when X/Rp<1.5 is satisfied, a current flowing to ground via the vacuum container 110 is large. Therefore, the influence of the state of the inner surface of the vacuum container 110 (the electrical characteristic of a film formed on the inner surface) is conspicuous, and the plasma potential changes depending on formation of a film. Thus, as described above, the plasma processing apparatus 1 is advantageously configured to satisfy 1.5≤X/Rp≤5000.

A method of deciding Rp−jXp (it is desired to actually know only Rp) will be exemplified with reference to FIG. 7. The balun 103 is detached from the plasma processing apparatus 1 and an output terminal 230 of the impedance matching circuit 102 is connected to the first terminal 251 (blocking capacitor 104) of the main body 10. Furthermore, the second terminal 252 (second electrode 111) of the main body 10 is grounded. In this state, the high-frequency power supply 101 supplies a high frequency to the first terminal 251 of the main body 10 via the impedance matching circuit 102. In the example shown in FIG. 7, the impedance matching circuit 102 is equivalently formed by coils L1 and L2 and variable capacitors VC1 and VC2. It is possible to generate plasma by adjusting the capacitance values of the variable capacitors VC1 and VC2. In the state in which the plasma is stable, the impedance of the impedance matching circuit 102 matches the impedance Rp−jXp on the side of the main body 10 (the side of the first electrode 106 and the second electrode 111) when the plasma is generated. The impedance of the impedance matching circuit 102 at this time is given by Rp+jXp.

Therefore, Rp−jXp (it is desired to actually know only Rp) can be obtained based on the impedance Rp+jXp of the impedance matching circuit 102 when the impedance is matched. Alternatively, for example, Rp−jXp can be obtained by simulation based on design data.

Based on Rp obtained in this way, X/Rp can be specified. For example, the reactance component (inductance component) X of the impedance of the first coil 221 of the balun 103 can be decided based on Rp so as to satisfy 1.5≤X/Rp≤5000.

FIG. 8 schematically shows the arrangement of a plasma processing apparatus 1 according to the second embodiment of the present invention. The plasma processing apparatus 1 according to the second embodiment can operate as an etching apparatus that etches a substrate 112. In the second embodiment, a first electrode 106 serves as a cathode, and holds the substrate 112. In the second embodiment, a second electrode 111 serves as an anode. In the plasma processing apparatus 1 according to the second embodiment, the first electrode 106 and a first balanced terminal 211 are electrically connected via a blocking capacitor 104. In other words, in the plasma processing apparatus 1 according to the second embodiment, the blocking capacitor 104 is arranged in an electrical connection path between the first electrode 106 and the first balanced terminal 211.

FIG. 9 schematically shows the arrangement of a plasma processing apparatus 1 according to the third embodiment of the present invention. The plasma processing apparatus 1 according to the third embodiment is a modification of the plasma processing apparatus 1 according to the first embodiment, and further includes at least one of a mechanism for vertically moving a second electrode 111 and a mechanism for rotating the second electrode 111. In the example shown in FIG. 9, the plasma processing apparatus 1 includes a driving mechanism 114 having both the mechanism for vertically moving the second electrode 111 and the mechanism for rotating the second electrode 111. A bellows 113 forming a vacuum partition can be provided between a vacuum container 110 and the driving mechanism 114.

Similarly, the plasma processing apparatus 1 according to the second embodiment can further include at least one of a mechanism for vertically moving the first electrode 106 and a mechanism for rotating the first electrode 106.

FIG. 10 schematically shows the arrangement of a plasma processing apparatus 1 according to the fourth embodiment of the present invention. The plasma processing apparatus according to the fourth embodiment can operate as a sputtering apparatus that forms a film on a substrate 112 by sputtering. Items which are not referred to as the plasma processing apparatus 1 according to the fourth embodiment can comply with the first to third embodiments. The plasma processing apparatus 1 includes a first balun 103, a second balun 303, a vacuum container 110, a first electrode 106 and a second electrode 135 constituting the first pair, and a first electrode 141 and a second electrode 145 constituting the second pair. Alternatively, it may be understood that the plasma processing apparatus 1 includes the first balun 103, the second balun 303, and a main body 10, and the main body 10 includes the vacuum container 110, the first electrode 106 and the second electrode 135 constituting the first pair, and the first electrode 141 and the second electrode 145 constituting the second pair. The main body 10 includes a first terminal 251, a second terminal 252, a third terminal 451, and a fourth terminal 452.

The first balun 103 includes a first unbalanced terminal 201, a second unbalanced terminal 202, a first balanced terminal 211, and a second balanced terminal 212. An unbalanced circuit is connected to the first unbalanced terminal 201 and the second unbalanced terminal 202 of the first balun 103, and a balanced circuit is connected to the first balanced terminal 211 and the second balanced terminal 212 of the first balun 103. The second balun 303 can have an arrangement similar to that of the first balun 103. The second balun 303 includes a first unbalanced terminal 401, a second unbalanced terminal 402, a first balanced terminal 411, and a second balanced terminal 412. An unbalanced circuit is connected to the first unbalanced terminal 401 and the second unbalanced terminal 402 of the second balun 303, and a balanced circuit is connected to the first balanced terminal 411 and the second balanced terminal 412 of the second balun 303. The vacuum container 110 is grounded.

The first electrode 106 of the first pair holds a target 109. The target 109 can be, for example, an insulator material or a conductor material. The second electrode 135 of the first pair is arranged around the first electrode 106. The first electrode 106 of the first pair is electrically connected to the first balanced terminal 211 of the first balun 103, and the second electrode 135 of the first pair is electrically connected to the second balanced terminal 212 of the first balun 103. The first electrode 141 of the second pair holds the substrate 112. The second electrode 145 of the second pair is arranged around the first electrode 141. The first electrode 141 of the second pair is electrically connected to the first balanced terminal 411 of the second balun 303, and the second electrode 145 of the second pair is electrically connected to the second balanced terminal 412 of the second balun 303.

The above arrangement can be understood as an arrangement in which the first electrode 106 of the first pair is electrically connected to the first terminal 251, the second electrode 135 of the first pair is electrically connected to the second terminal 252, the first terminal 251 is electrically connected to the first balanced terminal 211 of the first balun 103, and the second terminal 252 is electrically connected to the second balanced terminal 212 of the first balun 103. The above arrangement can be understood as an arrangement in which the first electrode 141 of the second pair is electrically connected to the third terminal 451, the second electrode 145 of the second pair is electrically connected to the fourth terminal 452, the third terminal 451 is electrically connected to the first balanced terminal 411 of the second balun 303, and the fourth terminal 452 is electrically connected to the second balanced terminal 412 of the second balun 303.

The first electrode 106 of the first pair and the first balanced terminal 211 (first terminal 251) of the first balun 103 can electrically be connected via a blocking capacitor 104. The blocking capacitor 104 blocks a DC current between the first balanced terminal 211 of the first balun 103 and the first electrode 106 of the first pair (or between the first balanced terminal 211 and the second balanced terminal 212 of the first balun 103). Instead of providing the blocking capacitor 104, a first impedance matching circuit 102 may be configured to block a DC current flowing between the first unbalanced terminal 201 and the second unbalanced terminal 202 of the first balun 103. The first electrode 106 and the second electrode 135 of the first pair can be supported by the vacuum container 110 via an insulator 132.

The first electrode 141 of the second pair and the first balanced terminal 411 (third terminal 451) of the second balun 303 can electrically be connected via a blocking capacitor 304. The blocking capacitor 304 blocks a DC current between the first balanced terminal 411 of the second balun 303 and the first electrode 141 of the second pair (or between the first balanced terminal 411 and the second balanced terminal 412 of the second balun 303). Instead of providing the blocking capacitor 304, a second impedance matching circuit 302 may be configured to block a DC current flowing between the first unbalanced terminal 201 and the second unbalanced terminal 202 of the second balun 303. The first electrode 141 and the second electrode 145 of the second pair can be supported by the vacuum container 110 via an insulator 142.

The plasma processing apparatus 1 can include a first high-frequency power supply 101, and the first impedance matching circuit 102 arranged between the first high-frequency power supply 101 and the first balun 103. The first high-frequency power supply 101 supplies a high frequency between the first unbalanced terminal 201 and the second unbalanced terminal 202 of the first balun 103 via the first impedance matching circuit 102. In other words, the first high-frequency power supply 101 supplies a high frequency between the first electrode 106 and the second electrode 135 via the first impedance matching circuit 102, the first balun 103, and the blocking capacitor 104. Alternatively, the first high-frequency power supply 101 supplies a high frequency between the first terminal 251 and the second terminal 252 of the main body 10 via the first impedance matching circuit 102 and the first balun 103. The first balun 103 and the first electrode 106 and the second electrode 135 of the first pair form the first high-frequency supply unit that supplies a high frequency to the internal space of the vacuum container 110.

The plasma processing apparatus 1 can include a second high-frequency power supply 301, and the second impedance matching circuit 302 arranged between the second high-frequency power supply 301 and the second balun 303. The second high-frequency power supply 301 supplies a high frequency between the first unbalanced terminal 401 and the second unbalanced terminal 402 of the second balun 303 via the second impedance matching circuit 302. In other words, the second high-frequency power supply 301 supplies a high frequency between the first electrode 141 and the second electrode 145 of the second pair via the second impedance matching circuit 302, the second balun 303, and the blocking capacitor 304. Alternatively, the second high-frequency power supply 301 supplies a high frequency between the third terminal 451 and the fourth terminal 452 of the main body 10 via the second impedance matching circuit 302 and the second balun 303. The second balun 303 and the first electrode 141 and the second electrode 145 of the second pair form the second high-frequency supply unit that supplies a high frequency to the internal space of the vacuum container 110.

Let Rp1−jXp1 be an impedance when viewing the side of the first electrode 106 and the second electrode 135 of the first pair (the side of the main body 10) from the side of the first balanced terminal 211 and the second balanced terminal 212 of the first balun 103 in a state in which plasma is generated in the internal space of the vacuum container 110 by supplying a high frequency from the first high-frequency power supply 101. Let X1 be the reactance component (inductance component) of the impedance of a first coil 221 of the first balun 103. In this definition, satisfying 1.5≤X1/Rp1≤5000 is advantageous in stabilizing the potential of the plasma formed in the internal space of the vacuum container 110.

In addition, let Rp2−jXp2 be an impedance when viewing the side of the first electrode 141 and the second electrode 145 of the second pair (the side of the main body 10) from the side of the first balanced terminal 411 and the second balanced terminal 412 of the second balun 303 in a state in which plasma is generated in the internal space of the vacuum container 110 by supplying a high frequency from the second high-frequency power supply 301. Let X2 be the reactance component (inductance component) of the impedance of the first coil 221 of the second balun 303. In this definition, satisfying 1.5≤X2/Rp2≤5000 is advantageous in stabilizing the potential of the plasma formed in the internal space of the vacuum container 110.

FIG. 11 schematically shows the arrangement of a plasma processing apparatus 1 according to the fifth embodiment of the present invention. The apparatus 1 according to the fifth embodiment has an arrangement obtained by adding driving mechanisms 114 and 314 to the plasma processing apparatus 1 according to the fourth embodiment. The driving mechanism 114 can include at least one of a mechanism for vertically moving a first electrode 141 and a mechanism for rotating the first electrode 141. The driving mechanism 314 can include a mechanism for vertically moving a second electrode 145.

FIG. 12 schematically shows the arrangement of a plasma processing apparatus 1 according to the sixth embodiment of the present invention. The plasma processing apparatus according to the sixth embodiment can operate as a sputtering apparatus that forms a film on a substrate 112 by sputtering. Items which are not referred to as the sixth embodiment can comply with the first to fifth embodiments. The plasma processing apparatus 1 according to the sixth embodiment includes a plurality of first high-frequency supply units and at least one second high-frequency supply unit. One of the plurality of first high-frequency supply units can include a first electrode 106a, a second electrode 135a, and a first balun 103a. Another one of the plurality of first high-frequency supply units can include a first electrode 106b, a second electrode 135b, and a first balun 103b. An example in which the plurality of first high-frequency supply units are formed by two high-frequency supply units will be described. In addition, the two high-frequency supply units and constituent elements associated with them are distinguished from each other using subscripts a and b. Similarly, two targets are distinguished from each other using subscripts a and b.

From another viewpoint, the plasma processing apparatus 1 includes the plurality of first baluns 103a and 103b, a second balun 303, a vacuum container 110, the first electrode 106a and the second electrode 135a, the first electrode 106b and the second electrode 135b, and a first electrode 141 and a second electrode 145. Alternatively, it may be understood that the plasma processing apparatus 1 includes the plurality of first baluns 103a and 103b, the second balun 303, and a main body 10, and the main body 10 includes the vacuum container 110, the first electrode 106a and the second electrode 135a, the first electrode 106b and the second electrode 135b, and the first electrode 141 and the second electrode 145. The main body 10 includes first terminals 251a and 251b, second terminals 252a and 252b, a third terminal 451, and a fourth terminal 452.

The first balun 103a includes a first unbalanced terminal 201a, a second unbalanced terminal 202a, a first balanced terminal 211a, and a second balanced terminal 212a. An unbalanced circuit is connected to the first unbalanced terminal 201a and the second unbalanced terminal 202a of the first balun 103a, and a balanced circuit is connected to the first balanced terminal 211a and the second balanced terminal 212a of the first balun 103a. The first balun 103b includes a first unbalanced terminal 201b, a second unbalanced terminal 202b, a first balanced terminal 211b, and a second balanced terminal 212b. An unbalanced circuit is connected to the first unbalanced terminal 201b and the second unbalanced terminal 202b of the first balun 103b, and a balanced circuit is connected to the first balanced terminal 211b and the second balanced terminal 212b of the first balun 103b.

The second balun 303 can have an arrangement similar to that of the first balun 103a or 103b. The second balun 303 includes a first unbalanced terminal 401, a second unbalanced terminal 402, a first balanced terminal 411, and a second balanced terminal 412. An unbalanced circuit is connected to the first unbalanced terminal 401 and the second unbalanced terminal 402 of the second balun 303, and a balanced circuit is connected to the first balanced terminal 411 and the second balanced terminal 412 of the second balun 303. The vacuum container 110 is grounded.

The first electrodes 106a and 106b hold targets 109a and 109b, respectively. Each of the targets 109a and 109b can be, for example, an insulator material or a conductor material. The second electrodes 135a and 135b are arranged around the first electrodes 106a and 106b, respectively. The first electrodes 106a and 106b are electrically connected to the first balanced terminals 211a and 211b of the first baluns 103a and 103b, respectively, and the second electrodes 135a and 135b are electrically connected to the second balanced terminals 212a and 212b of the first baluns 103a and 103b, respectively.

The first electrode 141 holds the substrate 112. The second electrode 145 is arranged around the first electrode 141. The first electrode 141 is electrically connected to the first balanced terminal 411 of the second balun 303, and the second electrode 145 is electrically connected to the second balanced terminal 412 of the second balun 303.

The above arrangement can be understood as an arrangement in which the first electrodes 106a and 106b are electrically connected to the first terminals 251a and 251b, respectively, the second electrodes 135a and 135b are electrically connected to the second terminals 252a and 252b, respectively, the first terminals 251a and 251b are electrically connected to the first balanced terminals 211a and 111b of the first baluns 103a and 103b, respectively, and the second terminals 252a and 252b are electrically connected to the second balanced terminals 212a and 212b of the first baluns 103a and 103b, respectively. The above arrangement can be understood as an arrangement in which the first electrode 141 is electrically connected to the third terminal 451, the second electrode 145 is electrically connected to the fourth terminal 452, the third terminal 451 is electrically connected to the first balanced terminal 411 of the second balun 303, and the fourth terminal 452 is electrically connected to the second balanced terminal 412 of the second balun 303.

The first electrodes 106a and 106b and the first balanced terminals 211a and 211b (first terminals 251a and 251b) of the first baluns 103a and 103b can electrically be connected via blocking capacitors 104a and 104b, respectively. The blocking capacitors 104a and 104b block DC currents between the first electrodes 106a and 106b and the first balanced terminals 211a and 211b of the first baluns 103a and 103b (or between the first balanced terminals 211a and 211b and the second balanced terminals 212a and 212b of the first baluns 103a and 103b), respectively. Instead of providing the blocking capacitors 104a and 104b , first impedance matching circuits 102a and 102b may be configured to block DC currents flowing between the first unbalanced terminals 201a and 201b and the second unbalanced terminals 202a and 202b of the first baluns 103a and 103b, respectively. Alternatively, the blocking capacitors 104a and 104b may be arranged between the second electrodes 135a and 135b and the second balanced terminals 212a and 212b (second terminals 252a and 252b) of the first baluns 103a and 103b, respectively. The first electrodes 106a and 106b and the second electrodes 135a and 135b can be supported by the vacuum container 110 via insulators 132a and 132b, respectively.

The first electrode 141 and the first balanced terminal 411 (third terminal 451) of the second balun 303 can electrically be connected via a blocking capacitor 304. The blocking capacitor 304 blocks a DC current between the first electrode 141 and the first balanced terminal 411 of the second balun 303 (or between the first balanced terminal 411 and the second balanced terminal 412 of the second balun 303). Instead of providing the blocking capacitor 304, a second impedance matching circuit 302 may be configured to block a DC current flowing between the first unbalanced terminal 201 and the second unbalanced terminal 202 of the second balun 303. Alternatively, the blocking capacitor 304 may be arranged between the second electrode 145 and the second balanced terminal 412 (fourth terminal 452) of the second balun 303. The first electrode 141 and the second electrode 145 can be supported by the vacuum container 110 via an insulator 142.

The plasma processing apparatus 1 can include a plurality of first high-frequency power supplies 101a and 101b, and the first impedance matching circuits 102a and 102b respectively arranged between the plurality of first high-frequency power supplies 101a and 101b and the plurality of first baluns 103a and 103b. The first high-frequency power supplies 101a and 101b supply high frequencies between the first unbalanced terminals 201a and 201b and the second unbalanced terminals 202a and 202b of the first baluns 103a and 103b via the first impedance matching circuits 102a and 102b, respectively. In other words, the first high-frequency power supplies 101a and 101b supply high frequencies between the first electrodes 106a and 106b and the second electrodes 135a and 135b via the first impedance matching circuits 102a and 102b, the first baluns 103a and 103b, and the blocking capacitors 104a and 104b, respectively. Alternatively, the first high-frequency power supplies 101a and 101b; supply high frequencies between the first terminals 251a and 251b and the second terminals 252a and 252b of the main body 10 via the first impedance matching circuits 102a and 101b and the first baluns 103a and 103b.

The plasma processing apparatus 1 can include a second high-frequency power supply 301, and the second impedance matching circuit 302 arranged between the second high-frequency power supply 301 and the second balun 303. The second high-frequency power supply 301 supplies a high frequency between the first unbalanced terminal 401 and the second unbalanced terminal 402 of the second balun 303 via the second impedance matching circuit 302. In other words, the second high-frequency power supply 301 supplies a high frequency between the first electrode 141 and the second electrode 145 via the second impedance matching circuit 302, the second balun 303, and the blocking capacitor 304. Alternatively, the second high-frequency power supply 301 supplies a high frequency between the third terminal 451 and the fourth terminal 452 of the main body 10 via the second impedance matching circuit 302 and the second balun 303.

FIG. 13 schematically shows the arrangement of a plasma processing apparatus 1 according to the seventh embodiment of the present invention. The plasma processing apparatus according to the seventh embodiment can operate as a sputtering apparatus that forms a film on a substrate 112 by sputtering. Items which are not referred to as the plasma processing apparatus 1 according to the seventh embodiment can comply with the first to sixth embodiments. The plasma processing apparatus 1 includes a first balun 103, a second balun 303, a vacuum container 110, a first electrode 105a and a second electrode 105b constituting the first pair, and a first electrode 141 and a second electrode 145 constituting the second pair. Alternatively, it may be understood that the plasma processing apparatus 1 includes the first balun 103, the second balun 303, and a main body 10, and the main body 10 includes the vacuum container 110, the first electrode 105a and the second electrode 105b constituting the first pair, and the first electrode 141 and the second electrode 145 constituting the second pair. The main body 10 includes a first terminal 251, a second terminal 252, a third terminal 451 and a fourth terminal 452.

The first electrode 105a of the first pair holds a first target 109a, and opposes a space on the side of the substrate 112 via the first target 109a. The second electrode 105b of the first pair is arranged adjacent to the first electrode 105a, holds a second target 105b, and opposes the space on the side of the substrate 112 via the second target 109b. Each of the targets 109a and 109b can be, for example, an insulator material or a conductor material. The first electrode 105a of the first pair is electrically connected to the first balanced terminal 211 of the first balun 103, and the second electrode 105b of the first pair is electrically connected to the second balanced terminal 212 of the first balun 103.

The first electrode 141 of the second pair holds the substrate 112. The second electrode 145 of the second pair is arranged around the first electrode 141. The first electrode 141 of the second pair is electrically connected to the first balanced terminal 411 of the second balun 303, and the second electrode 145 of the second pair is electrically connected to the second balanced terminal 412 of the second balun 303.

The above arrangement can be understood as an arrangement in which the first electrode 105a of the first pair is electrically connected to the first terminal 251, the second electrode 105b of the first pair is electrically connected to the second terminal 252, the first terminal 251 is electrically connected to the first balanced terminal 211 of the first balun 103, and the second terminal 252 is connected to the second balanced terminal 212 of the first balun 103. Furthermore, the above arrangement can be understood as an arrangement in which the first electrode 141 of the second pair is electrically connected to the third terminal 451, the second electrode 145 of the second pair is electrically connected to the fourth terminal 452, the third terminal 451 is electrically connected to the first balanced terminal 411 of the second balun 303, and the fourth terminal 452 is connected to the second balanced terminal 412 of the second balun 303.

The first electrode 105a of the first pair and the first balanced terminal 211 (first terminal 251) of the first balun 103 can electrically be connected via a blocking capacitor 104a. The blocking capacitor 104a blocks a DC current between the first balanced terminal 211 of the first balun 103 and the first electrode 105a of the first pair (or between the first balanced terminal 211 and the second balanced terminal 212 of the first balun 103). The second electrode 105b of the first pair and the second balanced terminal 212 (second terminal 252) of the first balun 103 can electrically be connected via a blocking capacitor 104b. The blocking capacitor 104b blocks a DC current between the second balanced terminal 212 of the first balun 103 and the second electrode 105b of the first pair (or between the first balanced terminal 211 and the second balanced terminal 212 of the first balun 103). The first electrode 105a and the second electrode 105b of the first pair can be supported by the vacuum container 110 via insulators 132a and 132b, respectively.

The first electrode 141 of the second pair and the first balanced terminal 411 (third terminal 451) of the second balun 303 can electrically be connected via a blocking capacitor 304. The blocking capacitor 304 blocks a DC current between the first balanced terminal 411 of the second balun 303 and the first electrode 141 of the second pair (or between the first balanced terminal 411 and the second balanced terminal 412 of the second balun 303). Instead of providing the blocking capacitor 304, a second impedance matching circuit 302 may be configured to block a DC current flowing between the first unbalanced terminal 401 and the second unbalanced terminal 402 of the second balun 303. The first electrode 141 and the second electrode 145 of the second pair can be supported by the vacuum container 110 via insulators 142 and 146, respectively.

The plasma processing apparatus 1 can include a first high-frequency power supply 101, and a first impedance matching circuit 102 arranged between the first high-frequency power supply 101 and the first balun 103. The first high-frequency power supply 101 supplies a high frequency between the first electrode 105a and the second electrode 105b via the first impedance matching circuit 102, the first balun 103, and the blocking capacitors 104a and 104b. Alternatively, the first high-frequency power supply 101 supplies a high frequency between the first terminal 251 and the second terminal 252 of the main body 10 via the first impedance matching circuit 102 and the first balun 103. The first balun 103 and the first electrode 105a and the second electrode 105b of the first pair form the first high-frequency supply unit that supplies a high frequency to the internal space of the vacuum container 110.

The plasma processing apparatus 1 can include a second high-frequency power supply 301, and the second impedance matching circuit 302 arranged between the second high-frequency power supply 301 and the second balun 303. The second high-frequency power supply 301 supplies a high frequency between the first unbalanced terminal 401 and the second unbalanced terminal 402 of the second balun 303 via the second impedance matching circuit 302. The second high-frequency power supply 301 supplies a high frequency between the first electrode 141 and the second electrode 145 of the second pair via the second impedance matching circuit 302, the second balun 303, and the blocking capacitor 304. Alternatively, the second high-frequency power supply 301 supplies a high frequency between the third terminal 451 and the fourth terminal 452 of the main body 10 via the second impedance matching circuit 302 and the second balun 303. The second balun 303 and the first electrode 141 and the second electrode 145 of the second pair form the second high-frequency supply unit that supplies a high frequency to the internal space of the vacuum container 110.

Let Rp1−jXp1 be an impedance when viewing the side of the first electrode 105a and the second electrode 105b of the first pair (the side of the main body 10) from the side of the first balanced terminal 211 and the second balanced terminal 212 of the first balun 103 in a state in which plasma is generated in the internal space of the vacuum container 110 by supplying a high frequency from the first high-frequency power supply 101. Let X1 be the reactance component (inductance component) of the impedance of a first coil 221 of the first balun 103. In this definition, satisfying 1.5≤X1/Rp1≤5000 is advantageous in stabilizing the potential of the plasma formed in the internal space of the vacuum container 110.

In addition, let Rp2−jXp2 be an impedance when viewing the side of a first electrode 127 and a second electrode 130 of the second pair (the side of the main body 10) from the side of the first balanced terminal 411 and the second balanced terminal 412 of the second balun 303 in a state in which plasma is generated in the internal space of the vacuum container 110 by supplying a high frequency from the second high-frequency power supply 301. Let X2 be the reactance component (inductance component) of the impedance of a first coil 221 of the second balun 303. In this definition, satisfying 1.5≤X2/Rp2≤5000 is advantageous in stabilizing the potential of the plasma formed in the internal space of the vacuum container 110.

The plasma processing apparatus 1 according to the seventh embodiment can further include at least one of a mechanism for vertically moving the first electrode 141 constituting the second pair and a mechanism for rotating the first electrode 141 constituting the second pair. In the example shown in FIG. 13, the plasma processing apparatus 1 includes a driving mechanism 114 having both the mechanism for vertically moving the first electrode 141 and the mechanism for rotating the first electrode 141. Furthermore, in the example shown in FIG. 13, the plasma processing apparatus 1 includes a mechanism 314 for vertically moving the second electrode 145 constituting the second pair. Bellows forming vacuum partitions can be provided between the vacuum container 110 and the driving mechanisms 114 and 314.

The function of the first balun 103 in the plasma processing apparatus 1 according to the seventh embodiment shown in FIG. 13 will be described with reference to FIG. 14. Let I1 be a current flowing through the first unbalanced terminal 201, I2 be a current flowing through the first balanced terminal 211, I2′ be a current flowing through the second unbalanced terminal 202, and I3 be a current, of the current I2, flowing to ground. When I3=0, that is, no current flows to ground on the balanced circuit side, the isolation performance of the balanced circuit with respect to ground is highest. When I3=I2, that is, all the current 12 flowing through the first balanced terminal 211 flows to ground, the isolation performance of the balanced circuit with respect to ground is lowest. Similar to the first to fifth embodiments, an index ISO representing the degree of the isolation performance is given by an equation below. Under this definition, as the absolute value of the index ISO is larger, the isolation performance is higher.

ISO [dB]=20 log(I3/I2′)

In FIG. 14, Rp−jXp (=Rp/2−jXp/2+Rp/2−jXp/2) represents an impedance (including the reactances of the blocking capacitors 104a and 104b) when viewing the side of the first electrode 105a and the second electrode 105b (the side of the main body 10) from the side of the first balanced terminal 211 and the second balanced terminal 212 in a state in which plasma is generated in the internal space of the vacuum container 110. Rp represents a resistance component, and −Xp represents a reactance component. Furthermore, in FIG. 14, X represents the reactance component (inductance component) of the impedance of the first coil 221 of the balun 103. ISO has a correlation with X/Rp.

FIG. 4 referred to in the description of the first embodiment exemplifies the relationship among the currents I1 (=I2), I2′, and I3, ISO, and α (=X/Rp). The relationship shown in FIG. 4 also holds in the seventh embodiment. The present inventor found that in the seventh embodiment as well, satisfying 1.5≤X/Rp≤5000 is advantageous in making the potential (plasma potential) of plasma formed in the internal space (the space between the first electrode 105a and the second electrode 105b) of the vacuum container 110 insensitive to the state of the inner surface of the vacuum container 110. When the plasma potential is insensitive to the state of the inner surface of the vacuum container 110, this indicates that it is possible to stabilize the plasma potential even if the plasma processing apparatus 1 is used for a long period. 1.5≤X/Rp≤5000 corresponds to −10.0 dB≥ISO≥=80 dB.

FIGS. 15A to 15D each show the plasma potential, the potential (cathode 1 potential) of the first electrode 105a, and the potential (cathode 2 potential) of the second electrode 105b when 1.5≤X/Rp≤5000 is satisfied. FIG. 15A shows the plasma potential, the potential (cathode 1 potential) of the first electrode 105a, and the potential (cathode 2 potential) of the second electrode 105b in a state in which a resistive film (1 mΩ) is formed on the inner surface of the vacuum container 110. FIG. 15B shows the plasma potential, the potential (cathode 1 potential) of the first electrode 105a, and the potential (cathode 2 potential) of the second electrode 105b in a state in which a resistive film (1,000 Ω) is formed on the inner surface of the vacuum container 110. FIG. 15C shows the plasma potential, the potential (cathode 1 potential) of the first electrode 105a, and the potential (cathode 2 potential) of the second electrode 105b in a state in which an inductive film (0.6 μH) is formed on the inner surface of the vacuum container 110. FIG. 15D shows the plasma potential, the potential (cathode 1 potential) of the first electrode 105a, and the potential (cathode 2 potential) of the second electrode 105b in a state in which a capacitive film (0.1 nF) is formed on the inner surface of the vacuum container 110. With reference to FIGS. 15A to 15D, it is understood that satisfying 1.5≤X/Rp≤5000 is advantageous in stabilizing the plasma potential in various states of the inner surface of the vacuum container 110.

FIGS. 16A to 16D each show a result of simulating the plasma potential, the potential (cathode 1 potential) of the first electrode 105a, and the potential (cathode 2 potential) of the second electrode 105b when 1.5≤X/Rp≤5000 is not satisfied. FIG. 16A shows the plasma potential, the potential (cathode 1 potential) of the first electrode 105a, and the potential (cathode 2 potential) of the second electrode 105b in a state in which a resistive film (1 mΩ) is formed on the inner surface of the vacuum container 110. FIG. 16B shows the plasma potential, the potential (cathode 1 potential) of the first electrode 105a, and the potential (cathode 2 potential) of the second electrode 105b in a state in which a resistive film (1,000 Ω) is formed on the inner surface of the vacuum container 110. FIG. 16C shows the plasma potential, the potential (cathode 1 potential) of the first electrode 105a, and the potential (cathode 2 potential) of the second electrode 105b in a state in which an inductive film (0.6 μH) is formed on the inner surface of the vacuum container 110. FIG. 16D shows the plasma potential, the potential (cathode 1 potential) of the first electrode 105a, and the potential (cathode 2 potential) of the second electrode 105b in a state in which a capacitive film (0.1 nF) is formed on the inner surface of the vacuum container 110. With reference to FIGS. 16A to 16D, it is understood that when 1.5≤X/Rp≤5000 is not satisfied, the plasma potential changes depending on the state of the inner surface of the vacuum container 110.

In both the case in which X/Rp>5000 (for example, X/Rp=∞) is satisfied and the case in which X/Rp<1.5 (for example, X/Rp=1.16 or X/Rp=0.87) is satisfied, the plasma potential readily changes depending on the state of the inner surface of the vacuum container 110. If X/Rp>5000 is satisfied, in a state in which no film is formed on the inner surface of the vacuum container 110, discharge occurs only between the first electrode 105a and the second electrode 105b. However, if X/Rp>5000 is satisfied, when a film starts to be formed on the inner surface of the vacuum container 110, the plasma potential sensitively reacts to this, and the results exemplified in FIGS. 16A to 16D are obtained. On the other hand, when X/Rp<1.5 is satisfied, a current flowing to ground via the vacuum container 110 is large. Therefore, the influence of the state of the inner surface of the vacuum container 110 (the electrical characteristic of a film formed on the inner surface) is conspicuous, and the plasma potential changes depending on formation of a film. Thus, as described above, the plasma processing apparatus 1 is advantageously configured to satisfy 1.5≤X/Rp≤5000.

FIG. 17 schematically shows the arrangement of a plasma processing apparatus 1 according to the eighth embodiment of the present invention. The plasma processing apparatus according to the eighth embodiment can operate as a sputtering apparatus that forms a film on a substrate 112 by sputtering. Items which are not referred to as the plasma processing apparatus 1 according to the eighth embodiment can comply with the first to seventh embodiments. The plasma processing apparatus 1 according to the eighth embodiment includes a balun (first balun) 103, a vacuum container 110, a first electrode 105a, a second electrode 105b, and a ground electrode 400. Alternatively, it may be understood that the plasma processing apparatus 1 includes the balun 103 and a main body 10, and the main body 10 includes the vacuum container 110, the first electrode 105a, the second electrode 105b, and the ground electrode 400. The main body 10 includes a first terminal 251 and a second terminal 252.

The ground electrode 400 is arranged in the vacuum container 110, and grounded. The ground electrode 400 can include a plurality of plate portions PLT arranged to be parallel to each other. The plurality of plate portions PLT can be arranged so that the ground electrode 400 has a comb-tooth shape in one section (for example, a section along the vertical direction). From another viewpoint, the ground electrode 400 can have a comb-tooth shape in one section (for example, a section along the vertical direction). This arrangement of the ground electrode 400 can contribute to an increase in area of a portion functioning as an anode. Furthermore, this arrangement of the ground electrode 400 is advantageous in suppressing formation of a film on the ground electrode 400 when forming a film on the substrate 112.

The first electrode 105a can include a first holding surface HS1 that holds a first target 109a as the first member, and the second electrode 105b can include a second holding surface HS2 that holds a second target 109b as the second member. The first holding surface HS1 and the second holding surface HS2 can belong to one plane PL. The ground electrode 400 can be arranged to intersect the plane PL. The ground electrode 400 can include, for example, a portion arranged between the first electrode 105a and the second electrode 105b. The ground electrode 400 can include, for example, a portion arranged between the first target 109a as the first member and the second target 109b as the second member. The ground electrode 400 is advantageous in suppressing formation of a film on the ground electrode 400 when forming a film on the substrate 112.

The plasma processing apparatus 1 according to the eighth embodiment may further include a second balun 303, a third electrode 141, and a fourth electrode 145. In other words, the plasma processing apparatus 1 can include the first balun 103, the second balun 303, the vacuum container 110, the first electrode 105a, the second electrode 105b, the third electrode 141, and the fourth electrode 145. Alternatively, it may be understood that the plasma processing apparatus 1 includes the first balun 103, the second balun 303, and the main body 10, and the main body 10 includes the vacuum container 110, the first electrode 105a, the second electrode 105b, the third electrode 141, and the fourth electrode 145. The third electrode 141 and the fourth electrode 145 are arranged to oppose the plane PL. The main body 10 includes the first terminal 251, the second terminal 252, a third terminal 451, and a fourth terminal 452.

The first balun 103 includes a first unbalanced terminal 201, a second unbalanced terminal 202, a first balanced terminal 211, and a second balanced terminal 212. An unbalanced circuit is connected to the first unbalanced terminal 201 and the second unbalanced terminal 202 of the first balun 103, and a balanced circuit is connected to the first balanced terminal 211 and the second balanced terminal 212 of the first balun 103. The second balun 303 can have an arrangement similar to that of the first balun 103. The second balun 303 includes a third unbalanced terminal 401, a fourth unbalanced terminal 402, a third balanced terminal 411, and a fourth balanced terminal 412. An unbalanced circuit is connected to the third unbalanced terminal 401 and the fourth unbalanced terminal 402 of the second balun 303, and a balanced circuit is connected to the third balanced terminal 411 and the fourth balanced terminal 412 of the second balun 303. The vacuum container 110 is grounded. Each of the baluns 103 and 303 can have the arrangement shown in FIG. 2A or 2B (FIG. 14).

The first electrode 105a holds the first target 109a, and opposes a space on the side of the substrate 112 as a processing target via the first target 109a. The second electrode 105b is arranged adjacent to the first electrode 105a, holds the second target 109b, and opposes the space on the side of the substrate 112 as a processing target via the second target 109b. Each of the targets 109a and 109b can be, for example, an insulator material or a conductor material. The first electrode 105a is electrically connected to the first balanced terminal 211 of the first balun 103, and the second electrode 105b is electrically connected to the second balanced terminal 212 of the first balun 103.

The third electrode 141 holds the substrate 112. The fourth electrode 145 can be arranged around the third electrode 141. The third electrode 141 is electrically connected to the first balanced terminal 411 of the second balun 303, and the fourth electrode 145 is electrically connected to the second balanced terminal 412 of the second balun 303.

The above arrangement can be understood as an arrangement in which the first electrode 105a is electrically connected to the first terminal 251, the second electrode 105b is electrically connected to the second terminal 252, the first terminal 251 is electrically connected to the first balanced terminal 211 of the first balun 103, and the second terminal 252 is connected to the second balanced terminal 212 of the first balun 103. The above arrangement can be understood as an arrangement in which the third electrode 141 is electrically connected to the third terminal 451, the fourth electrode 145 is electrically connected to the fourth terminal 452, the third terminal 451 is electrically connected to the first balanced terminal 411 of the second balun 303, and the fourth terminal 452 is connected to the second balanced terminal 412 of the second balun 303.

The first electrode 105a and the first balanced terminal 211 (first terminal 251) of the first balun 103 can electrically be connected via a blocking capacitor 104a. The blocking capacitor 104a blocks a DC current between the first balanced terminal 211 of the first balun 103 and the first electrode 105a (or between the first balanced terminal 211 and the second balanced terminal 212 of the first balun 103). The second electrode 105b and the second balanced terminal 212 (second terminal 252) of the first balun 103 can electrically be connected via a blocking capacitor 104b. The blocking capacitor 104b blocks a DC current between the second balanced terminal 212 of the first balun 103 and the second electrode 105b (or between the first balanced terminal 211 and the second balanced terminal 212 of the first balun 103). The first electrode 105a and the second electrode 105b can be supported by the vacuum container 110 via insulators 132a and 132b, respectively.

The third electrode 141 and the first balanced terminal 411 (third terminal 451) of the second balun 303 can electrically be connected via a blocking capacitor 304. The blocking capacitor 304 blocks a DC current between the first balanced terminal 411 of the second balun 303 and the third electrode 141 (or between the first balanced terminal 411 and the second balanced terminal 412 of the second balun 303). Instead of providing the blocking capacitor 304, a second impedance matching circuit 302 may be configured to block a DC current flowing between the first unbalanced terminal 401 and the second unbalanced terminal 402 of the second balun 303. The third electrode 141 and the fourth electrode 145 can be supported by the vacuum container 110 via insulators 142 and 146, respectively.

The plasma processing apparatus 1 can include a first high-frequency power supply 101, and a first impedance matching circuit 102 arranged between the first high-frequency power supply 101 and the first balun 103. The first high-frequency power supply 101 supplies a high frequency between the first electrode 105a and the second electrode 105b via the first impedance matching circuit 102, the first balun 103, and the blocking capacitors 104a and 104b. Alternatively, the first high-frequency power supply 101 supplies a high frequency between the first terminal 251 and the second terminal 252 of the main body 10 via the first impedance matching circuit 102 and the first balun 103. The first balun 103, the first electrode 105a, and the second electrode 105b form the first high-frequency supply unit that supplies a high frequency to the internal space of the vacuum container 110.

The plasma processing apparatus 1 can include a second high-frequency power supply 301, and the second impedance matching circuit 302 arranged between the second high-frequency power supply 301 and the second balun 303. The second high-frequency power supply 301 supplies a high frequency between the first unbalanced terminal 401 and the second unbalanced terminal 402 of the second balun 303 via the second impedance matching circuit 302. The second high-frequency power supply 301 supplies a high frequency between the third electrode 141 and the fourth electrode 145 via the second impedance matching circuit 302, the second balun 303, and the blocking capacitor 304. Alternatively, the second high-frequency power supply 301 supplies a high frequency between the third terminal 451 and the fourth terminal 452 of the main body 10 via the second impedance matching circuit 302 and the second balun 303. The second balun 303, the third electrode 141, and the fourth electrode 145 form the second high-frequency supply unit that supplies a high frequency to the internal space of the vacuum container 110.

Let Rp1−jXp1 be an impedance when viewing the side of the first electrode 105a and the second electrode 105b (the side of the main body 10) from the side of the first balanced terminal 211 and the second balanced terminal 212 of the first balun 103 in a state in which plasma is generated in the internal space of the vacuum container 110 by supplying a high frequency from the first high-frequency power supply 101. Let X1 be the reactance component (inductance component) of the impedance of a first coil 221 of the first balun 103. In this definition, satisfying 1.5≤X1/Rp1≤5000 is advantageous in stabilizing the potential of the plasma formed in the internal space of the vacuum container 110. Note that satisfying the condition of 1.5≤X/Rp1≤5000 is not essential to the eighth embodiment and is an advantageous condition. In the eighth embodiment, even if the condition of 1.5≤X/Rp1≤5000 is not satisfied, it is possible to obtain the effect of making the potential (plasma potential) of the plasma formed in the internal space (the space between the first electrode 106 and the second electrode 111) of the vacuum container 110 insensitive to the state of the inner surface of the vacuum container 110 by providing the ground electrode 400 in the vacuum container 110.

In addition, let Rp2−jXp2 be an impedance when viewing the side of the third electrode 141 and the fourth electrode 145 (the side of the main body 10) from the side of the first balanced terminal 411 and the second balanced terminal 412 of the second balun 303 in a state in which plasma is generated in the internal space of the vacuum container 110 by supplying a high frequency from the second high-frequency power supply 301. Let X2 be the reactance component (inductance component) of the impedance of the first coil 221 of the second balun 303. In this definition, satisfying 1.5≤X2/Rp2≤5000 is advantageous in stabilizing the potential of the plasma formed in the internal space of the vacuum container 110. Note that satisfying the condition of 1.5≤X/Rp2≤5000 is not essential to the eighth embodiment and is an advantageous condition. In the eighth embodiment, even if the condition of 1.5≤X/Rp2≤5000 is not satisfied, it is possible to obtain the effect of making the potential (plasma potential) of the plasma formed in the internal space (the space between the first electrode 106 and the second electrode 111) of the vacuum container 110 insensitive to the state of the inner surface of the vacuum container 110 by providing the ground electrode 400 in the vacuum container 110.

The plasma processing apparatus 1 according to the eighth embodiment can further include at least one of a mechanism for vertically moving the third electrode 141 and a mechanism for rotating the third electrode 141. In the example shown in FIG. 17, the plasma processing apparatus 1 includes a driving mechanism 114 having both the mechanism for vertically moving the third electrode 141 and the mechanism for rotating the third electrode 141. Furthermore, in the example shown in FIG. 17, the plasma processing apparatus 1 includes a mechanism 314 for vertically moving the fourth electrode 145. Bellows forming vacuum partitions can be provided between the vacuum container 110 and the driving mechanisms 114 and 314.

A comparative example will be described below with reference to FIGS. 18 to 21. As shown in FIG. 18, a plasma processing apparatus 1′ according to the comparative example has a structure obtained by eliminating the baluns 103 and 303 and the ground electrode 400 from the plasma processing apparatus 1 according to the eighth embodiment. Note that in FIG. 18, a third electrode 141 and a fourth electrode 145 are not illustrated. FIGS. 19 to 21 each show a simulation result of a plasma potential, the potential (cathode 1 potential) of a first electrode 105a, and the potential (cathode 2 potential) of a second electrode 105b. In this simulation, high-frequency power supplies 101a and 101b are set to generate a voltage of 100 sin(ωt) [V]. The radius of each of the first electrode 105a and the second electrode 105b is set to 10 cm. In addition, in FIGS. 19 to 21, [cathode 1 area:ground area:cathode 2 area] represents [the area of the first electrode 105a]:[the area of a portion of the vacuum container 110, which functions as an anode]:[the area of the second electrode 105b].

FIG. 19 shows a simulation result when cathode 1 area:ground area:cathode 2 area is 1:0.5:1. FIG. 20 shows a simulation result when cathode 1 area:ground area:cathode 2 area is 1:1:1. FIG. 21 shows a simulation result when cathode 1 area:ground area:cathode 2 area is 1:3:1. When forming a film on a substrate 112 by sputtering, a film can also be formed on the inner surface of a vacuum container 110. This can change the state of the inner surface of the vacuum container 110, for example, the area (ground area) of the portion of the vacuum container 110, which functions as an anode. With reference to the results shown in FIGS. 19 to 21, the plasma potential can change due to a change in ground area. This indicates that if film formation is continued for a plurality of substrates, the plasma potential can change to change the characteristic for forming a film. Furthermore, the results shown in FIGS. 19 to 21, a larger area (ground area) of the portion of the vacuum container 110, which functions as an anode is more effective in suppressing a change in plasma potential.

On the other hand, according to the eighth embodiment, it is possible to stabilize the potential of the plasma formed in the internal space of the vacuum container 110 by providing the balun 103 and the ground electrode 400 and satisfying the condition of 1.5≤X/Rp1≤5000, as described above. Alternatively, it is possible to stabilize the potential of the plasma formed in the internal space of the vacuum container 110 by providing the baluns 103 and 303 and the ground electrode 400 and satisfying the conditions of 1.5≤X/Rp1≤5000 and 1.5≤X/Rp2≤5000.

Furthermore, according to the eighth embodiment, even if the condition of 1.5≤X/Rp1≤5000 is not satisfied, it is possible to stabilize the potential of the plasma formed in the internal space of the vacuum container 110 by providing the balun 103 and the ground electrode 400. Alternatively, according to the eighth embodiment, even if the conditions of 1.5≤X/Rp1≤5000 and 1.5≤X/Rp2≤5000 are not satisfied, it is possible to stabilize the potential of the plasma formed in the internal space of the vacuum container 110 by providing the balun 103 and the ground electrode 400.

FIG. 22 schematically shows the arrangement of a plasma processing apparatus 1 according to the ninth embodiment of the present invention. The plasma processing apparatus 1 according to the ninth embodiment can operate as an etching apparatus that etches substrates 112a and 112b. The plasma processing apparatus 1 according to the ninth embodiment is different from that according to the eighth embodiment in that a first electrode 105a and a second electrode 105b hold the first substrate 112a and the second substrate 112b to be etched, respectively, and a third electrode 141 holds no substrate. In terms of the remaining points, the plasma processing apparatus 1 according to the ninth embodiment can have an arrangement similar to that of the plasma processing apparatus 1 according to the eighth embodiment.

The present invention is not limited to the above-described embodiments, and various changes and modifications can be made within the spirit and scope of the present invention. Therefore, to apprise the public of the scope of the present invention, the following claims are made.

REFERENCE SIGNS LIST

1: plasma processing apparatus, 10: main body, 101: high-frequency power supply, 102: impedance matching circuit, 103: balun, 104: blocking capacitor, 106: first electrode, 107, 108: insulator, 109: target, 110: vacuum container, 111: second electrode, 112: substrate, 201: first unbalanced terminal, 202: second unbalanced terminal, 211: first balanced terminal, 212: second balanced terminal, 251: first terminal, 252: second terminal, 221: first coil, 222: second coil, 223: third coil, 224: fourth coil, 400: ground electrode, PLT: plate portion, PL: plane, HS1: first holding surface, HS2: second holding surface

Claims

1. A plasma processing apparatus comprising: a balun including a first unbalanced terminal, a second unbalanced terminal, a first balanced terminal, and a second balanced terminal;a grounded vacuum container;a first electrode electrically connected to the first balanced terminal;a second electrode electrically connected to the second balanced terminal; anda ground electrode arranged in the vacuum container and grounded,wherein the ground electrode includes a plurality of plate portions arranged to be parallel to each other.
2. The plasma processing apparatus according to claim 1, wherein the plurality of plate portions are arranged so that the ground electrode has a comb-tooth shape in a section.
3. The plasma processing apparatus according to claim 1, wherein the first electrode includes a first holding surface configured to hold a first member, the second electrode includes a second holding surface configured to hold a second member, and the first holding surface and the second holding surface belong to one plane.
4. The plasma processing apparatus according to claim 3, wherein the ground electrode is arranged to intersect the one plane.
5. The plasma processing apparatus according to claim 4, wherein the ground electrode includes a portion arranged between the first member and the second member.
6. The plasma processing apparatus according to claim 3, wherein the first holding surface opposes an internal space of the vacuum container via the first member, and the second holding surface opposes the internal space of the vacuum container via the second member.
7. The plasma processing apparatus according to claim 3, further comprising: a second balun including a third unbalanced terminal, a fourth unbalanced terminal, a third balanced terminal, and a fourth balanced terminal;a third electrode electrically connected to the third balanced terminal; anda fourth electrode electrically connected to the fourth balanced terminal,wherein the fourth electrode is arranged around the third electrode, andthe third electrode and the fourth electrode are arranged to oppose the one plane.
8. The plasma processing apparatus according to claim 7, wherein when Rp represents a resistance component between the first balanced terminal and the second balanced terminal when viewing a side of the first electrode and the second electrode from a side of the first balanced terminal and the second balanced terminal, and X represents an inductance between the first unbalanced terminal and the first balanced terminal, 1.5≤X/Rp ≤5000 is satisfied, andwhen Rp′ represents a resistance component between the third balanced terminal and the fourth balanced terminal when viewing a side of the third electrode and the fourth electrode from a side of the third balanced terminal and the fourth balanced terminal, and X′ represents an inductance between the third unbalanced terminal and the third balanced terminal, 1.5≤X′/Rp′≤5000 is satisfied.
9. The plasma processing apparatus according to claim 1, wherein the first balanced terminal and the first electrode are electrically connected via a blocking capacitor.
10. The plasma processing apparatus according to claim 1, wherein the second balanced terminal and the second electrode are electrically connected via a blocking capacitor.
11. The plasma processing apparatus according to claim 1 wherein the first balanced terminal and the first electrode are electrically connected via a blocking capacitor, and the second balanced terminal and the second electrode are electrically connected via a blocking capacitor.
12. The plasma processing apparatus according to claim 1, wherein the first electrode and the second electrode are supported by the vacuum container via insulators.
13. The plasma processing apparatus according to claim 1, wherein the balun includes a first coil configured to connect the first unbalanced terminal and the first balanced terminal, and a second coil configured to connect the second unbalanced terminal and the second balanced terminal.
14. The plasma processing apparatus according to claim 1, wherein the first electrode holds a first target, the second electrode holds a second target, the first electrode opposes a space on a side of a substrate as a processing target via the first target, and the second electrode opposes the space via the second target.
15. The plasma processing apparatus according to claim 1, wherein the first electrode holds a first substrate, the second electrode holds a second substrate, and the plasma processing apparatus is configured as an etching apparatus configured to etch the first substrate and the second substrate.
16. The plasma processing apparatus according to claim 1 further comprising: a high-frequency power supply; andan impedance matching circuit arranged between the high-frequency power supply and the balun.
17. The plasma processing apparatus according to claim 1, wherein when Rp represents a resistance component between the first balanced terminal and the second balanced terminal when viewing a side of the first electrode and the second electrode from a side of the first balanced terminal and the second balanced terminal, and X represents an inductance between the first unbalanced terminal and the first balanced terminal, 1.5≤X/Rp≤5000 is satisfied.
18. A plasma processing apparatus comprising: a balun including a first unbalanced terminal, a second unbalanced terminal, a first balanced terminal, and a second balanced terminal;a grounded vacuum container;a first electrode electrically connected to the first balanced terminal;a second electrode electrically connected to the second balanced terminal; anda ground electrode arranged in the vacuum container and grounded,wherein the ground electrode has a comb-tooth shape in a section.
19. A plasma processing apparatus comprising: a balun including a first unbalanced terminal, a second unbalanced terminal, a first balanced terminal, and a second balanced terminal;a grounded vacuum container formed by a conductor;a first electrode electrically connected to the first balanced terminal;a second electrode electrically connected to the second balanced terminal; anda ground electrode arranged in the vacuum container and grounded;wherein the balun includes a first coil configured to connect the first unbalanced terminal and the first balanced terminal, and a second coil configured to connect the second unbalanced terminal and the second balanced terminal, a third coil and a fourth coil both of which are connected between the first balanced terminal and the second balanced terminal, and the third coil and the fourth coil are configured to set, as a midpoint between a voltage of the first balanced terminal and a voltage of the second balanced terminal, a voltage of a connection node of the third coil and the fourth coil.

Priority Claims (3)

Number	Date	Country	Kind
PCT/JP2017/023603	Jun 2017	WO	international
PCT/JP2017/023611	Jun 2017	WO	international
JP2018-017548	Feb 2018	JP	national

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application is a continuation of International Patent Application No. PCT/JP2018/024154 filed on Jun. 26, 2018, which claims priority to and the benefit of International Patent Application No. PCT/JP2017/023611 filed Jun. 27, 2017, International Patent Application No. PCT/JP2017/023603 filed Jun. 27, 2017, and Japanese Patent Application No. 2018-017548 filed Feb. 2, 2018, the entire disclosures of which are incorporated herein by reference.

US Referenced Citations (138)

Number	Name	Date	Kind
4014779	Kuehnle	Mar 1977	A
4025339	Kuehnle	May 1977	A
4131533	Bialko et al.	Dec 1978	A
4170475	Hagenlocher et al.	Oct 1979	A
4284489	Weber	Aug 1981	A
4284490	Weber	Aug 1981	A
4584079	Lee	Apr 1986	A
4802080	Bossi	Jan 1989	A
4871421	Ogle	Oct 1989	A
4887005	Rough	Dec 1989	A
4956582	Bourassa	Sep 1990	A
5121067	Marsland	Jun 1992	A
5147493	Nishimura	Sep 1992	A
5169509	Latz et al.	Dec 1992	A
5316645	Yamagami et al.	May 1994	A
5330578	Sakama et al.	Jul 1994	A
5415757	Szcyrbowski et al.	May 1995	A
5464499	Moslehi et al.	Nov 1995	A
5611899	Maass	Mar 1997	A
5698082	Teschner et al.	Dec 1997	A
5718815	Szczyrbowski et al.	Feb 1998	A
5733511	De	Mar 1998	A
5755938	Fukui et al.	May 1998	A
5803973	Szczyrbowski et al.	Sep 1998	A
5807470	Szczyrbowski	Sep 1998	A
5830331	Kim et al.	Nov 1998	A
5865969	Clarke	Feb 1999	A
5932116	Matsumoto et al.	Aug 1999	A
5989999	Levine	Nov 1999	A
5990016	Kim et al.	Nov 1999	A
6017221	Flamm	Jan 2000	A
6046641	Chawla	Apr 2000	A
6096174	Teschner et al.	Aug 2000	A
6150826	Hokodate et al.	Nov 2000	A
6239404	Lea et al.	May 2001	B1
6252354	Collins	Jun 2001	B1
6273022	Pu et al.	Aug 2001	B1
6422172	Tanaka et al.	Jul 2002	B1
6517912	Morfill et al.	Feb 2003	B1
6568346	Pu et al.	May 2003	B2
6703080	Reyzelman et al.	Mar 2004	B2
6818103	Scholl et al.	Nov 2004	B1
6825618	Pu et al.	Nov 2004	B2
6876205	Walde et al.	Apr 2005	B2
6885154	Uchida et al.	Apr 2005	B2
6913703	Strang et al.	Jul 2005	B2
7032536	Fukuoka et al.	Apr 2006	B2
7298091	Pickard	Nov 2007	B2
7445690	Kasai	Nov 2008	B2
7586210	Wiedemuth	Sep 2009	B2
7670455	Keller et al.	Mar 2010	B2
7777567	Polizzo	Aug 2010	B2
8033246	Wiedemuth et al.	Oct 2011	B2
8293068	Koshimizu et al.	Oct 2012	B2
8450635	Dhindsa et al.	May 2013	B2
8647585	Hancock	Feb 2014	B2
8932430	Srivastava et al.	Jan 2015	B2
8992723	Sorensen et al.	Mar 2015	B2
9039864	Baek et al.	May 2015	B2
9121786	Tie	Sep 2015	B2
9147555	Richter	Sep 2015	B2
9245776	Himori et al.	Jan 2016	B2
9401265	Michel	Jul 2016	B2
9455126	Valcore, Jr.	Sep 2016	B2
9564360	Akasaka et al.	Feb 2017	B2
9607810	Valcore, Jr.	Mar 2017	B2
9620337	Valcore, Jr.	Apr 2017	B2
9640367	Keller et al.	May 2017	B2
9675716	Hancock	Jun 2017	B2
9779196	Valcore, Jr.	Oct 2017	B2
9875881	Nagami et al.	Jan 2018	B2
10081869	Augustyniak et al.	Sep 2018	B2
10083817	Godyak	Sep 2018	B1
10157729	Valcore, Jr.	Dec 2018	B2
RE47276	Benjamin	Mar 2019	E
10224463	Daigo	Mar 2019	B2
10231321	Valcore, Jr.	Mar 2019	B2
10354838	Mopidevi	Jul 2019	B1
10410889	Sadjadi et al.	Sep 2019	B2
10544505	Yang et al.	Jan 2020	B2
10553406	Chang et al.	Feb 2020	B2
10685810	Mopidevi	Jun 2020	B2
10879043	Selmo	Dec 2020	B2
11013075	Lester	May 2021	B2
11114287	Harris et al.	Sep 2021	B2
11170991	Sakane	Nov 2021	B2
11315765	Yamawaku et al.	Apr 2022	B2
20010054383	Pu et al.	Dec 2001	A1
20020022836	Goble	Feb 2002	A1
20030087044	Willms et al.	May 2003	A1
20030215373	Reyzelman et al.	Nov 2003	A1
20040222184	Hayami et al.	Nov 2004	A1
20040262156	Seymour et al.	Dec 2004	A1
20050136604	Al-bayati et al.	Jun 2005	A1
20050138577	Adamian	Jun 2005	A1
20050160987	Kasai et al.	Jul 2005	A1
20060032738	Wiedemuth	Feb 2006	A1
20080050537	Godyak	Feb 2008	A1
20080258411	Miura	Oct 2008	A1
20080308041	Koshiishi et al.	Dec 2008	A1
20090041640	Kasai et al.	Feb 2009	A1
20090075597	Degani et al.	Mar 2009	A1
20090085597	Burns	Apr 2009	A1
20090102385	Wi	Apr 2009	A1
20090117707	Shimomura et al.	May 2009	A1
20090242135	Koshimizu	Oct 2009	A1
20100252199	Marakhtanov	Oct 2010	A1
20100294433	Jianhui	Nov 2010	A1
20110300694	Matsumoto et al.	Dec 2011	A1
20130017315	Lai et al.	Jan 2013	A1
20130105082	Melikyan	May 2013	A1
20130337657	Savas	Dec 2013	A1
20140373783	Sawada et al.	Dec 2014	A1
20150054405	Nettesheim	Feb 2015	A1
20150165752	Piach et al.	Jun 2015	A1
20150170882	Yamawaku et al.	Jun 2015	A1
20150255258	Nozawa et al.	Sep 2015	A1
20160240351	Burgess et al.	Aug 2016	A1
20160289837	Savas	Oct 2016	A1
20160307743	Brown et al.	Oct 2016	A1
20160336084	Laguardia et al.	Nov 2016	A1
20170018401	Rudolph	Jan 2017	A1
20170084432	Valcore et al.	Mar 2017	A1
20170213734	Marakhtanov	Jul 2017	A9
20170232122	Hancock	Aug 2017	A1
20180130640	Gregor et al.	May 2018	A1
20180269035	Selmo	Sep 2018	A1
20180318459	Hancock	Nov 2018	A1
20190221405	Yamawaku et al.	Jul 2019	A1
20200126763	Sekiya	Apr 2020	A1
20200126764	Inoue	Apr 2020	A1
20200126766	Sekiya	Apr 2020	A1
20200126767	Takeda	Apr 2020	A1
20200126768	Inoue	Apr 2020	A1
20200161096	Chang et al.	May 2020	A1
20210005429	Tanabe	Jan 2021	A1
20210118649	Huh et al.	Apr 2021	A1
20220051878	Sekiya et al.	Feb 2022	A1

Foreign Referenced Citations (80)

Number	Date	Country
1155748	Jul 1997	CN
1220931	Jun 1999	CN
1390436	Jan 2003	CN
2907173	May 2007	CN
101425456	May 2009	CN
101478857	Jul 2009	CN
101546697	Sep 2009	CN
102479657	May 2012	CN
103091042	May 2013	CN
103094042	May 2013	CN
104024471	Sep 2014	CN
105887050	Aug 2016	CN
106024568	Oct 2016	CN
19713637	Oct 1998	DE
1748687	Jan 2007	EP
53-141937	Nov 1978	JP
S53141937	Nov 1978	JP
S55035465	Sep 1980	JP
S 62133065	Jun 1987	JP
H02501608	May 1990	JP
H02156080	Jun 1990	JP
H02156081	Jun 1990	JP
H02156082	Jun 1990	JP
H02156083	Jun 1990	JP
H04317325	Nov 1992	JP
H10261621	Sep 1998	JP
H11307299	Nov 1999	JP
2000030896	Jan 2000	JP
2000195851	Jul 2000	JP
2000294543	Oct 2000	JP
2001122690	May 2001	JP
2001181848	Jul 2001	JP
2001518230	Oct 2001	JP
2002004040	Jan 2002	JP
2002118101	Apr 2002	JP
2002141292	May 2002	JP
2003512526	Apr 2003	JP
2003155556	May 2003	JP
2005026540	Jan 2005	JP
2005130376	May 2005	JP
2005303257	Oct 2005	JP
2006336084	Dec 2006	JP
2008294465	Dec 2008	JP
2008300322	Dec 2008	JP
2009021634	Jan 2009	JP
2009105030	May 2009	JP
2009302566	Dec 2009	JP
2010045664	Feb 2010	JP
2010109157	May 2010	JP
2010255061	Nov 2010	JP
2011138907	Jul 2011	JP
2011144450	Jul 2011	JP
4909523	Apr 2012	JP
2012142332	Jul 2012	JP
2012174682	Sep 2012	JP
2013139642	Jul 2013	JP
2014049541	Mar 2014	JP
2015115216	Jun 2015	JP
5824072	Nov 2015	JP
2016225376	Dec 2016	JP
2017211144	Nov 2017	JP
6280677	Feb 2018	JP
6309683	Apr 2018	JP
10-2014-0135202	Nov 2014	KR
200741794	Nov 2007	TW
201311059	Mar 2013	TW
201423827	Jun 2014	TW
I492294	Jul 2015	TW
201532220	Aug 2015	TW
201643932	Dec 2016	TW
I560767	Dec 2016	TW
I575107	Mar 2017	TW
I 601309	Oct 2017	TW
8902695	Mar 1989	WO
0129278	Apr 2001	WO
0137619	May 2001	WO
2010024128	Mar 2010	WO
2010041679	Apr 2010	WO
2012095961	Jul 2012	WO
2019004191	Jan 2019	WO

Non-Patent Literature Citations (30)

Entry
International Search Report (PCT/ISA/210) and translation and Written Opinion (PCT/ISA/237) dated Sep. 11, 2018, by the Japanese Patent Office as the International Searching Authority for International Application No. PCT/JP2018/024150.
Office Action Summary dated Jan. 6, 2021, by the U.S. Patent and Trademark Office in U.S. Appl. No. 16/720,154. (27 pages).
Office Action Summary dated Mar. 15, 2021, by the U.S. Patent and Trademark Office in U.S. Appl. No. 16/720,154. (19 pages).
Supplemental European Search Report issued in corresponding European Patent Application No. 18824433, dated Apr. 30, 2020 (8 pages).
Supplemental European Search Report issued in corresponding European Patent Application No. 18823378.7, dated May 25, 2020 (7 pages).
Office Action (Notice of Preliminary Rejection) dated Apr. 19, 2021, by the Korean Patent Office in corresponding Korean Patent Application No. 10-2020-7001366, and an English Translation of the Office Action. (14 pages).
Office Action (Notice of Preliminary Rejection) dated Apr. 26, 2021, by the Korean Patent Office in corresponding Korean Patent Application No. 10-2020-7001366, and an English Translation of the Office Action. (9 pages).
Office Action (Grant of Patent) dated Apr. 27, 2021, by the Korean Patent Office in corresponding Korean Patent Application No. 10-2020-7001397, and an English Translation of the Office Action. (4 pages).
Office Action dated Aug. 19, 2021, by the U.S. Patent and Trademark Office in corresponding U.S. Appl. No. 17/023,675.
International Search Report (PCT/ISA/210) dated Sep. 4, 2018, by the Japanese Patent Office as the International Searching Authority for International Application No. PCT/JP2018/024154.
Written Opinion (PCT/ISA/237) dated Sep. 4, 2018, by the Japanese Patent Office as the International Searching Authority for International Application No. PCT/JP2018/024154.
Co-pending U.S. Appl. No. 17/023,675, filed Sep. 17, 2020.
Notice of Allowance dated Sep. 20, 2021, by the U.S. Patent and Trademark Office in U.S. Appl. No. 16/720,154.
Office Action dated Sep. 22, 2021, by the U.S. Patent and Trademark Office in U.S. Appl. No. 16/720,262.
First Office Action dated Jun. 2, 2021, by the Chinese Patent Office in Chinese Patent Application No. 201880042465, and an English Translation of the Office Action. (23 pages).
First Office Action dated Jun. 2, 2021, by the Chinese Patent Office in Chinese Patent Application No. 201880042477.2, and an English Translation of the Office Action. (20 pages).
First Office Action dated Jun. 2, 2021, by the Chinese Patent Office in Chinese Patent Application No. 201780092518.4, and an English Translation of the Office Action. (21 pages).
First Office Action dated Jun. 2, 2021, by the Chinese Patent Office in Chinese Patent Application No. 201780092519.9, and an English Translation of the Office Action. (23 pages).
First Office Action dated Jun. 3, 2021, by the Chinese Patent Office in Chinese Patent Application No. 201880042506.5, and an English Translation of the Office Action. (21 pages).
Extended European Search Report issued in European Patent Application No. 18 92 4031, dated Feb. 15, 2022, (9 pages). European Patent Application No. 18 92 4031 corresponds to U.S. Appl. No. 17/023,675.
Non-Final Office Action received for U.S. Appl. No. 16/720,087, dated Apr. 7, 2022, 24 pages.
Non Final Office Action received for U.S. Appl. No. 16/720,154, dated May 26, 2022, 16 pages.
Non Final Office Action received for U.S. Appl. No. 16/720,173, dated May 12, 2022, 26 pages.
Notice of Allowance received for U.S. Appl. No. 16/720,262, dated May 27, 2022, 8 pages.
Notice of Allowance received for U.S. Appl. No. 17/023,675, dated May 26, 2022, 12 pages.
Notice of Reasons for Refusal issued in corresponding Japanese Patent Application No. 2019-012426, dated Aug. 15, 2022, with English Translation (8 pages).
Notice of Reasons for Refusal issued in corresponding Japanese Patent Application No. 2019-012419, dated Aug. 15, 2022, with English Translation (14 pages).
Written Decision on Registration issued in Korean Patent Application No. 10-2020-7001366, dated Sep. 23, 2022, with English Translation (6 pages).
Final Office Action issued in U.S. Appl. No. 16/720,087, dated Oct. 25, 2022 (36 pages).
Notification of the First Office Action issued in Chinese Patent Application No. 201880094963.9, dated Oct. 10, 2022, with English Translation (33 pages).

Related Publications (1)

	Number	Date	Country
	20200126767 A1	Apr 2020	US

Continuations (1)

	Number	Date	Country
Parent	PCT/JP2018/024154	Jun 2018	US
Child	16720156		US

Plasma processing apparatus

Information

Patent Number

Date Filed

Date Issued

Inventors

Original Assignees

Examiners

Agents

CPC

Field of Search

US

International Classifications

Disclaimer

Term Extension

Abstract