TW201907754A - Plasma treatment device - Google Patents

Abstract

A plasma treatment device, comprising: a first balun that has a first unbalanced terminal, a second unbalanced terminal, a first balanced terminal, and a second balanced terminal; a second balun that has a third unbalanced terminal, a fourth unbalanced terminal, a third balanced terminal, and a fourth balanced terminal; a grounded vacuum container; a first electrode that is electrically connected to the first balanced terminal and the third balanced terminal; a second electrode that is electrically connected to the second balanced terminal; and a third electrode that is electrically connected to the fourth balanced terminal.

Description

Plasma processing device

The present invention relates to a plasma processing apparatus.

There is a plasma processing apparatus which processes a substrate by applying a high frequency between two electrodes to generate a plasma. Such a plasma processing apparatus can operate as a sputtering apparatus or as an etching apparatus by the area ratio and/or the bias voltage of the two electrodes. A plasma processing apparatus configured as a sputtering apparatus includes a first electrode that holds a target and a second electrode that holds a substrate, and a high frequency is applied between the first electrode and the second electrode, and the first electrode and the second electrode are A plasma is produced between the electrodes (between the target and the substrate). By the generation of plasma, a self-bias voltage is generated on the surface of the target, whereby ions collide with the target, and particles constituting the material are emitted from the target.

Patent Document 1 describes a sputtering apparatus including a chamber to be grounded, a target electrode connected to an RF generation source via an impedance matching circuit network, and a substrate holding electrode grounded via a substrate electrode tuning circuit.

In the sputtering apparatus as described in Patent Document 1, the chamber can function as an anode in addition to the substrate holding electrode. The self-bias voltage varies depending on the state that can be used as a part of the cathode function and the state that can be used as a part of the anode function. Therefore, when the chamber functions as an anode in addition to the substrate holding electrode, the self-bias voltage also changes depending on the state of the chamber as a part of the anode function. A change in the self-bias voltage causes a change in the plasma potential, and a change in the plasma potential affects the characteristics of the formed film.

When a film is formed on a substrate by a sputtering apparatus, a film is formed on the inner surface of the chamber. Thereby, the state of the chamber which can serve as a part of the anode function changes. Therefore, if the sputtering apparatus is continuously used, the self-bias voltage will vary depending on the film formed on the inner surface of the chamber, and the plasma potential will also change. Therefore, in the case where the sputtering apparatus has been used for a long period of time, it is difficult to maintain the characteristics of the film formed on the substrate constant.

Similarly, when the etching apparatus is used for a long period of time, since the self-bias voltage varies depending on the film formed on the inner surface of the chamber, the plasma potential also changes, so that it is difficult to maintain the etching characteristics of the substrate constant. . [Prior Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Publication No. Sho 55-35465

The present invention has been made in view of the above-mentioned problems, and has been proposed to provide a technique for making the plasma potential stable during long-term use.

According to a first aspect of the present invention, in a plasma processing apparatus, the plasma processing apparatus includes: a first balun having a first unbalanced terminal, a second unbalanced terminal, a first balanced terminal, and a second balanced terminal; a second balun having a third unbalanced terminal, a fourth unbalanced terminal, a third balanced terminal, and a fourth balanced terminal; a vacuum vessel that is grounded; and electrically connected to the first balanced terminal and the third balanced terminal a first electrode; a second electrode electrically connected to the second balanced terminal; and a third electrode electrically connected to the fourth balanced terminal.

Hereinafter, the present invention will be described by way of embodiments with reference to the accompanying drawings.

The configuration of the plasma processing apparatus 1 according to the first embodiment of the present invention is schematically shown in Fig. 1 . The plasma processing apparatus according to the first embodiment can operate as a sputtering apparatus that forms a film on the substrate 112 by sputtering. The plasma processing apparatus 1 includes a balun (balance unbalance conversion circuit) 103, a vacuum vessel 110, a first electrode 106, and a second electrode 111. Alternatively, it is also understood that the plasma processing apparatus 1 includes the balun 103 and the body 10, and the body 10 includes the vacuum container 110, the first electrode 106, and the second electrode 111. The main body 10 has a first terminal 251 and a second terminal 252. The first electrode 106 may be disposed to separate the vacuum space from the external space (that is, a part constituting the vacuum partition) together with the vacuum container 110, or may be disposed in the vacuum container 110. The second electrode 111 may be disposed to separate the vacuum space from the external space (that is, a part constituting the vacuum partition) together with the vacuum container 110, or may be disposed in the vacuum container 110.

The balun 103 has 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 side of the first unbalanced terminal 201 and the second unbalanced terminal 202 of the balun 103, and a balanced circuit is connected to the side of the first balanced terminal 211 and the second balanced terminal 212 of the balun 103. . The vacuum vessel 110 is made of a conductor and is grounded.

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

The above configuration may be understood to mean that the first electrode 106 is electrically connected to the first terminal 251, the second electrode 111 is electrically connected to the second terminal 252, and the first terminal 251 is electrically connected to the first balanced terminal 211. 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 the blocking capacitor 104. The blocking capacitor 104 blocks a direct 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 the blocking capacitor 104, the impedance matching circuit 102 described later may be configured to block a direct current flowing between the first unbalanced terminal 201 and the second unbalanced terminal 202. The first electrode 106 is supported by the vacuum vessel 110 via the insulator 107. The second electrode 111 can be supported by the vacuum vessel 110 via the insulator 108. Alternatively, an insulator 108 may be disposed between the second electrode 111 and the vacuum container 110.

The plasma processing apparatus 1 may further include a high-frequency power source 101 and an impedance matching circuit 102 disposed between the high-frequency power source 101 and the balun 103. The high frequency power supply 101 supplies a high frequency (high frequency current, high frequency voltage, high frequency power) to the first unbalanced terminal 201 of the balun 103 and the second unbalanced terminal 202 via the impedance matching circuit 102. In other words, the high-frequency power source 101 supplies high-frequency (high-frequency current, high-frequency voltage, high-frequency power) to the first electrode 106 and the second electrode 111 via the impedance matching circuit 102, the balun 103, and the blocking capacitor 104. Alternatively, it is also understood that the high-frequency power source 101 is supplied 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.

The internal space of the vacuum vessel 110 is supplied with a gas (for example, Ar, Kr, or Xe gas) via a gas supply unit (not shown) provided in the vacuum vessel 110. Further, between the first electrode 106 and the second electrode 111, a high frequency is supplied from the high frequency power source 101 via the impedance matching circuit 102, the balun 103, and the blocking capacitor 104. Thereby, a plasma is generated between the first electrode 106 and the second electrode 111, and a self-bias voltage is generated on the surface of the target 109, and ions in the plasma collide with the surface of the target 109 to be emitted from the target 109. The particles that make up the material of that. Then, a film is formed on the substrate 112 by the particles.

FIG. 2A shows a configuration example of the balun 103. The balun 103 shown in FIG. 2A is a first coil 221 having a first unbalanced terminal 201 and a 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 of the same number of windings, and have a common core.

FIG. 2B shows another configuration example of the balun 103. The balun 103 shown in FIG. 2B has 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 of the same number of windings, and have a common core. Further, the balun 103 shown in FIG. 2B has the third coil 223 and the fourth coil 224 connected to the first balanced terminal 211 and the second balanced terminal 212, and the third coil 223 and the fourth coil 224 are further provided. The voltage of the connection node 213 of the third coil 223 and the fourth coil 224 is set to be a midpoint between the voltage of the first balanced terminal 211 and the voltage of the second balanced terminal 212. The third coil 223 and the fourth coil 224 are coils of the same number of turns, and have a common core. The connection node 213 may also be grounded, may be connected to the vacuum vessel 110, or may be floated.

The function of the balun 103 will be described with reference to Fig. 3 . The current flowing through the first unbalanced terminal 201 is I1, the current flowing through the first balanced terminal 211 is I2, and the current flowing through the second unbalanced terminal 202 is I2', and the current flows in the current I2. The current to ground is set to I3. I3 = 0, that is, the balance circuit is optimal for the isolation performance of the ground when the side current of the balancing circuit does not flow to the ground. I3=I2, that is, when all of the current I2 flowing through the first balanced terminal 211 flows to the ground, the isolation circuit has the worst isolation performance for the ground. The index ISO indicating the degree of such isolation performance can be given the following formula. Under this definition, the absolute value of the ISO value is larger and the isolation performance is better. ISO[dB]=20log(I3/I2’)

In FIG. 3, Rp-jXp is a state in which the first electrode 106 and the second electrode 111 are viewed from the side of the first balanced terminal 211 and the second balanced terminal 212 in a state where plasma is generated in the internal space of the vacuum chamber 110. The impedance at the side (the side of the body 10) (including the reactance of the blocking capacitor 104). Rp represents a resistance component, and -Xp represents a reactance component. Further, in FIG. 3, X is a reactance component (inductance component) indicating the impedance of the first coil 221 of the balun 103. ISO is relevant for X/Rp.

The relationship of the currents I1 (=I2), I2', I3, ISO, and α (=X/Rp) is exemplified in Fig. 4 . The inventors of the present invention have found that a configuration in which a high frequency is supplied from the high-frequency power source 101 to the first electrode 106 and the second electrode 111 via the balun 103 is particularly advantageous in that it conforms to 1.5≦X/Rp≦5000 in this configuration. The electric potential (plasma potential) of the plasma formed in the internal space of the vacuum vessel 110 (the space between the first electrode 106 and the second electrode 111) is insensitive to the state of the inner surface of the vacuum vessel 110. Here, the fact that the plasma potential forms an insensitive feeling with respect to the state of the inner surface of the vacuum vessel 110 means that even if the plasma processing apparatus 1 is used for a long period of time, the plasma potential can be stabilized. 1.5≦X/Rp≦5000 is equivalent to -10.0dB≧ISO≧-80dB.

5A to 5D show the results of the plasma potential when the simulation conforms to 1.5 ≦X/Rp ≦ 5000 and the potential (cathode potential) of the first electrode 106. FIG. 5A is a view showing a plasma potential and a cathode potential in a state where a film is not formed on the inner surface of the vacuum vessel 110. FIG. 5B is a plasma potential and a cathode potential in a state in which a resistive film (1000 Ω) is formed on the inner surface of the vacuum vessel 110. 5C is a plasma potential and a cathode potential in a state in which an inductive film (0.6 μH) is formed on the inner surface of the vacuum vessel 110. 5D is a plasma potential and a cathode potential in a state in which a capacitive film (0.1 nF) is formed on the inner surface of the vacuum vessel 110. As can be understood from FIGS. 5A to 5D, conforming to 1.5 ≦ X / Rp ≦ 5000 will facilitate the stabilization of the plasma potential in various states for the inner surface of the vacuum vessel 110.

6A to 6D show the results of the plasma potential when the simulation does not conform to 1.5≦X/Rp≦5000 and the potential (cathode potential) of the first electrode 106. FIG. 6A is a view showing a plasma potential and a cathode potential in a state in which a film is not formed on the inner surface of the vacuum vessel 110. 6B is a plasma potential and a cathode potential in a state in which a resistive film (1000 Ω) is formed on the inner surface of the vacuum vessel 110. 6C is a plasma potential and a cathode potential in a state in which an inductive film (0.6 μH) is formed on the inner surface of the vacuum vessel 110. 6D is a plasma potential and a cathode potential in a state in which a capacitive film (0.1 nF) is formed on the inner surface of the vacuum vessel 110. 6A to 6D, when 1.5 ≦ X / Rp ≦ 5000 is not satisfied, the plasma potential changes depending on the state of the inner surface of the vacuum vessel 110.

Here, in the case of X/Rp>5000 (for example, X/Rp=∞) and the case of X/Rp<1.5 (for example, X/Rp=1.0, X/Rp=0.5), the plasma potential is easy to follow. The state of the inner surface of the vacuum vessel 110 changes. In the case of X/Rp>5000, a film is not formed on the inner surface of the vacuum vessel 110, and discharge occurs only between the first electrode 106 and the second electrode 111. However, in the case of X/Rp &gt; 5000, once the film is formed on the inner surface of the vacuum vessel 110, the plasma potential is sensitively reacted thereto, and the results are as exemplified in Figs. 6A to 6D. On the other hand, in the case of X/Rp<1.5, since the current flowing into the ground via the vacuum vessel 110 is large, the state of the inner surface of the vacuum vessel 110 (the electrical characteristics of the film formed on the inner surface) is caused. The effect is significant and the plasma potential will vary depending on the formation of the film. Therefore, as described above, it is advantageous to configure the plasma processing apparatus 1 so as to conform to 1.5 ≦ X / Rp ≦ 5000.

Referring to Fig. 7, a method of determining Rp-jXp (actually known as Rp only) is exemplified. First, the balun 103 is removed from the plasma processing apparatus 1, and the output terminal 230 of the impedance matching circuit 102 is connected to the first terminal 251 (blocking capacitor 104) of the body 10. Then, the second terminal 252 (second electrode 111) of the body 10 is grounded. In this state, the high frequency power supply 101 supplies the high frequency to the first terminal 251 of the body 10 via the impedance matching circuit 102. In the example shown in FIG. 7, the impedance matching circuit 102 is equivalently constituted by the coils L1, L2 and the variable capacitors VC1, VC2. The plasma can be generated by adjusting the capacitance values of the variable capacitors VC1, VC2. In the state in which the plasma is stabilized, the impedance of the impedance matching circuit 102 is matched to the impedance Rp-jXp of the side of the body 10 (the side of the first electrode 106 and the second electrode 111) at the time of plasma generation. The impedance of the impedance matching circuit 102 at this time is Rp+jXp.

Therefore, Rp-jXp can be obtained from the impedance Rp+jXp of the impedance matching circuit 102 at the time of impedance matching (actually, only Rp is known). Rp-jXp is other, for example, which can be obtained by simulation based on design data.

Based on the Rp thus obtained, 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 determined according to Rp so as to conform to 1.5 ≦ X / Rp ≦ 5000.

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

FIG. 9 is a view schematically showing the configuration of the plasma processing apparatus 1 according to the third embodiment of the present invention. The plasma processing apparatus 1 of the third embodiment is a modification of the plasma processing apparatus 1 of the first embodiment, and further includes at least one of a mechanism for moving the second electrode 111 up and down and a mechanism for rotating the second electrode 111. In the example shown in FIG. 9 , the plasma processing apparatus 1 is provided with a drive mechanism 114 including both a mechanism for moving the second electrode 111 up and down and a mechanism for rotating the second electrode 111 . A bellows 113 constituting a vacuum partition wall may be provided between the vacuum vessel 110 and the drive mechanism 114.

Similarly, the plasma processing apparatus 1 of the second embodiment may further include at least one of a mechanism for moving the first electrode 106 up and down and a mechanism for rotating the second electrode 106.

Fig. 10 is a view schematically showing the configuration of a plasma processing apparatus 1 according to a fourth embodiment of the present invention. The plasma processing apparatus of the fourth embodiment operates as a sputtering apparatus that forms a film on the substrate 112 by sputtering. The matters not described in the plasma processing apparatus 1 of the fourth embodiment are in accordance 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 group, and a first electrode 141 and a first electrode constituting the second group. 2 electrode 145. Alternatively, it is also understood that the plasma processing apparatus 1 includes a first balun 103, a second balun 303, and a body 10. The main body 10 includes a vacuum container 110, and a first electrode 106 and a second electrode constituting the first group. 135. The first electrode 141 and the second electrode 145 of the second group are formed. The main body 10 has a first terminal 251, a second terminal 252, a third terminal 451, and a fourth terminal 452.

The first balun 103 has a first unbalanced terminal 201, a second unbalanced terminal 202, a first balanced terminal 211, and a second balanced terminal 212. On the side of the first unbalanced terminal 201 and the second unbalanced terminal 202 of the first balun 103, an unbalanced circuit is connected, and the side of the first balanced terminal 211 and the second balanced terminal 212 of the first balun 103 is A balanced circuit is connected. The second balun 303 may have the same configuration as the first balun 103. The second balun 303 has a first unbalanced terminal 401, a second unbalanced terminal 402, a first balanced terminal 411, and a second balanced terminal 412. On the side of the first unbalanced terminal 401 and the second unbalanced terminal 402 of the second balun 303, an unbalanced circuit is connected, and the side of the first balanced terminal 411 and the second balanced terminal 412 of the second balun 303 is A balanced circuit is connected. The vacuum vessel 110 is grounded.

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

The above configuration is understood to be that the first electrode 106 of the first group is electrically connected to the first terminal 251, the second electrode 135 of the first group is electrically connected to the second terminal 252, and the first terminal 251 is electrically connected. The second balanced terminal 211 is 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. Further, the above configuration is understood to be that the first electrode 141 of the second group is electrically connected to the third terminal 451, the second electrode 145 of the second group is electrically connected to the fourth terminal 452, and the third terminal 451 is The fourth terminal 452 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 group and the first balanced terminal 211 (first terminal 251) of the first balun 103 are electrically connectable via the blocking capacitor 104. The blocking capacitor 104 is shielded between the first balanced terminal 211 of the first balun 103 and the first electrode 106 of the first group (or between the first balanced terminal 211 and the second balanced terminal 212 of the first balun 103). Broken DC current. Instead of the blocking capacitor 104, the first impedance matching circuit 102 may block the 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 group are supported by the vacuum vessel 110 via the insulator 132.

The first electrode 141 of the second group and the first balanced terminal 411 (third terminal 451) of the second balun 303 are electrically connectable via the blocking capacitor 304. The blocking capacitor 304 is shielded between the first balanced terminal 411 of the second balun 303 and the first electrode 141 of the second group (or between the first balanced terminal 411 and the second balanced terminal 412 of the second balun 303). Broken DC current. Instead of the blocking capacitor 304, the second impedance matching circuit 302 may block the 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 group are supported by the vacuum vessel 110 via the insulator 142.

The plasma processing apparatus 1 may include a first high-frequency power source 101 and a first impedance matching circuit 102 disposed between the first high-frequency power source 101 and the first balun 103. The first high-frequency power source 101 is supplied between the first unbalanced terminal 201 and the second unbalanced terminal 202 whose high frequency is supplied to the first balun 103 via the first impedance matching circuit 102. In other words, the first high-frequency power source 101 supplies a high frequency to 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 source 101 supplies a high frequency to 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 group constitute a first high-frequency supply unit that supplies a high frequency to the internal space of the vacuum container 110.

The plasma processing apparatus 1 may include a second high frequency power supply 301 and a second impedance matching circuit 302 disposed between the second high frequency power supply 301 and the second balun 303. The second high-frequency power source 301 is supplied between the first unbalanced terminal 401 and the second unbalanced terminal 402 whose frequency is supplied to the second balun 303 via the second impedance matching circuit 302. In other words, the second high-frequency power source 301 supplies the high frequency to the first electrode 141 and the second electrode 145 of the second group via the second impedance matching circuit 302, the second balun 303, and the blocking capacitor 304. Alternatively, the second high-frequency power source 301 supplies a high frequency to 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 group constitute a second high-frequency supply unit that supplies a high frequency to the internal space of the vacuum container 110.

By the supply of the high frequency power from the first high frequency power supply 101, the plasma is generated in the internal space of the vacuum container 110, and the first balanced terminal 211 and the second balanced terminal 212 of the first balun 103 are provided. When the first electrode 106 of the first group and the side of the second electrode 135 (the side of the body 10) are viewed, the impedance is Rp1-jXp1. Further, the reactance component (inductance component) of the impedance of the first coil 221 of the first balun 103 is set to X1. In this definition, conforming to 1.5 ≦ X1/Rp1 ≦ 5000 is advantageous for stabilizing the potential of the plasma formed in the internal space of the vacuum vessel 110.

In addition, in the state where the plasma is generated in the internal space of the vacuum container 110 by the high frequency supply from the second high frequency power supply 301, the first balanced terminal 411 and the second balanced terminal 412 of the second balun 303 are placed. The impedance when the first electrode 141 of the second group and the side of the second electrode 145 (the side of the body 10) are viewed from the side is Rp2-jXp2. Further, the reactance component (inductance component) of the impedance of the first coil 221 of the second balun 303 is set to X2. In this definition, conforming to 1.5≦X2/Rp2≦5000 is advantageous for stabilizing the potential of the plasma formed in the internal space of the vacuum vessel 110.

Fig. 11 is a view schematically showing the configuration of a plasma processing apparatus 1 according to a fifth embodiment of the present invention. The apparatus 1 of the fifth embodiment has a configuration in which the drive mechanisms 114 and 314 are added to the plasma processing apparatus 1 of the fourth embodiment. The drive mechanism 114 is at least one of a mechanism that can raise and lower the first electrode 141 and a mechanism that rotates the first electrode 141. The drive mechanism 314 is a mechanism that can raise and lower the second electrode 145.

Fig. 12 is a view schematically showing the configuration of a plasma processing apparatus 1 according to a sixth embodiment of the present invention. The plasma processing apparatus of the sixth embodiment is operable as a sputtering apparatus that forms a film on the substrate 112 by sputtering. The matters not described in the sixth embodiment are in accordance with the first to fifth embodiments. The plasma processing apparatus 1 of 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 may include the first electrode 106a, the second electrode 135a, and the first balun 103a. The other of the plurality of first high-frequency supply units may include the first electrode 106b, the second electrode 135b, and the first balun 103b. Here, an example in which a plurality of first high-frequency supply units are configured by two high-frequency supply units will be described. Further, the following symbols a and b distinguish the two high-frequency supply units and their associated components. Similarly, the two targets are also distinguished by the following symbols a and b.

In another aspect, the plasma processing apparatus 1 includes a plurality of first baluns 103a and 103b, a second balun 303, a vacuum vessel 110, first electrodes 106a and second electrodes 135a, first electrodes 106b, and second. The electrode 135b, the first electrode 141, and the second electrode 145. Alternatively, the plasma processing apparatus 1 may include a plurality of first baluns 103a and 103b, a second balun 303, and a body 10. The main body 10 includes a vacuum container 110, a first electrode 106a, and a second electrode 135a. The first electrode 106b and the second electrode 135b, 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 has a first unbalanced terminal 201a, a second unbalanced terminal 202a, a first balanced terminal 211a, and a second balanced terminal 212a. On the side of the first unbalanced terminal 201a and the second unbalanced terminal 202a of the first balun 103a, an unbalanced circuit is connected, and the side of the first balanced terminal 211a and the second balanced terminal 212a of the first balun 103a is A balanced circuit is connected. 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. On the side of the first unbalanced terminal 201b and the second unbalanced terminal 202b of the first balun 103b, an unbalanced circuit is connected, and the side of the first balanced terminal 211b and the second balanced terminal 212b of the first balun 103b is A balanced circuit is connected.

The second balun 303 may have the same configuration as the first baluns 103a and 103b. The second balun 303 has a first unbalanced terminal 401, a second unbalanced terminal 402, a first balanced terminal 411, and a second balanced terminal 412. On the side of the first unbalanced terminal 401 and the second unbalanced terminal 402 of the second balun 303, an unbalanced circuit is connected, and the side of the first balanced terminal 411 and the second balanced terminal 412 of the second balun 303 is A balanced circuit is connected. The vacuum vessel 110 is grounded.

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

The first electrode 141 is a holding substrate 112. The second electrode 145 is disposed 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 configuration is understood to be that the first electrodes 106a and 106b are electrically connected to the first terminals 251a and 251b, respectively, and the second electrodes 135a and 135b are electrically connected to the second terminals 252a and 252b, respectively, and the first terminal 251a. 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. Composition. Further, the above configuration is understood to mean that the first electrode 141 is electrically connected to the third terminal 451, the second electrode 145 is electrically connected to the fourth terminal 452, and the third terminal 451 is electrically connected to the second terminal 451. The first balanced terminal 411 of the 303 and the fourth terminal 452 are 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 (the first terminals 251a and 251b) of the first baluns 103a and 103b are electrically connectable via the blocking capacitors 104a and 104b, respectively. The blocking capacitors 104a and 104b are between the first balanced terminals 211a and 211b of the first baluns 103a and 103b and the first electrodes 106a and 106b (or the first balanced terminals 211a and 211b of the first baluns 103a and 103b and the first 2 between the balanced terminals 212a and 212b) blocks the direct current. Instead of the blocking capacitors 104a and 104b, the first impedance matching circuits 102a and 102b may block the first unbalanced terminals 201a and 201b flowing between the first baluns 103a and 103b and the second unbalanced terminals 202a and 202b. The method of DC current is formed. Alternatively, the blocking capacitors 104a and 104b may be disposed between the second electrodes 135a and 135b and the second balanced terminals 212a and 212b (the second terminals 252a and 252b) of the first baluns 103a and 103b. The first electrodes 106a and 106b and the second electrodes 135a and 135b are supported by the vacuum vessel 110 via the insulators 132a and 132b, respectively.

The first electrode 141 and the first balanced terminal 411 (third terminal 451) of the second balun 303 are electrically connectable via the blocking capacitor 304. The blocking capacitor 304 blocks the DC current between the first balanced terminal 411 of the second balun 303 and the first electrode 141 (or between the first balanced terminal 411 and the second balanced terminal 412 of the second balun 303). Instead of the blocking capacitor 304, the second impedance matching circuit 302 may block the 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 disposed 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 are supported by the vacuum vessel 110 via the insulator 142.

The plasma processing apparatus 1 may include a plurality of first high-frequency power sources 101a and 101b, and first ones disposed between the plurality of first high-frequency power sources 101a and 101b and the plurality of first baluns 103a and 103b. Impedance matching circuits 102a, 102b. The first high-frequency power sources 101a and 101b supply the first unbalanced terminals 201a and 201b and the second unbalanced terminals 202a and 202b that are high-frequency to the first baluns 103a and 103b via the first impedance matching circuits 102a and 102b, respectively. between. In other words, the first high-frequency power sources 101a and 101b supply the high-frequency to the first electrodes 106a and 106b and the second electrode via the first impedance matching circuits 102a and 102b, the first baluns 103a and 103b, and the blocking capacitors 104a and 104b, respectively. Between 135a and 135b. Alternatively, the first high-frequency power sources 101a and 101b supply the high-frequency to the first terminals 251a and 251b of the main body 10 and the second terminals 252a and 252b via the first impedance matching circuits 102a and 102b and the first baluns 103a and 103b. between.

The plasma processing apparatus 1 may include a second high frequency power supply 301 and a second impedance matching circuit 302 disposed between the second high frequency power supply 301 and the second balun 303. The second high-frequency power source 301 is supplied between the first unbalanced terminal 401 and the second unbalanced terminal 402 whose frequency is supplied to the second balun 303 via the second impedance matching circuit 302. In other words, the second high-frequency power source 301 supplies a high frequency to 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 source 301 supplies a high frequency to 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 is a view schematically showing the configuration of a plasma processing apparatus 1 according to a seventh embodiment of the present invention. The plasma processing apparatus of the seventh embodiment operates as a sputtering apparatus that forms a film on the substrate 112 by sputtering. The matters not described in the plasma processing apparatus 1 of the seventh embodiment are in accordance 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 group, and a first electrode 141 and a first electrode constituting the second group. 2 electrode 145. Alternatively, the plasma processing apparatus 1 may include a first balun 103, a second balun 303, and a body 10. The main body 10 includes a vacuum container 110, and a first electrode 105a and a second electrode constituting the first group. 105b. The first electrode 141 and the second electrode 145 of the second group are formed. The main body 10 has a first terminal 251, a second terminal 252, a third terminal 451, and a fourth terminal 452.

The first balun 103 has a first unbalanced terminal 201, a second unbalanced terminal 202, a first balanced terminal 211, and a second balanced terminal 212. On the side of the first unbalanced terminal 201 and the second unbalanced terminal 202 of the first balun 103, an unbalanced circuit is connected, and the side of the first balanced terminal 211 and the second balanced terminal 212 of the first balun 103 is A balanced circuit is connected. The second balun 303 may have the same configuration as the first balun 103. The second balun 303 has a first unbalanced terminal 401, a second unbalanced terminal 402, a first balanced terminal 411, and a second balanced terminal 412. On the side of the first unbalanced terminal 401 and the second unbalanced terminal 402 of the second balun 303, an unbalanced circuit is connected, and the side of the first balanced terminal 411 and the second balanced terminal 412 of the second balun 303 is A balanced circuit is connected. The vacuum vessel 110 is grounded.

The first electrode 105a of the first group holds the first target 109a and faces the space on the side of the substrate 112 via the first target 109a. The second electrode 105b of the first group is disposed beside the first electrode 105a, and holds the second target 109b, and faces the space on the side of the substrate 112 via the second target 109b. The targets 109a and 109b may be, for example, an insulator material or a conductor material. The first electrode 105a of the first group is electrically connected to the first balanced terminal 211 of the first balun 103, and the second electrode 105b of the first group is electrically connected to the second balanced terminal of the first balun 103. 212.

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

The above configuration is understood to be that the first electrode 105a of the first group is electrically connected to the first terminal 251, the second electrode 105b of the first group is electrically connected to the second terminal 252, and the first terminal 251 is electrically connected. The second balanced terminal 211 is 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. Further, the above configuration is understood to be that the first electrode 141 of the second group is electrically connected to the third terminal 451, the second electrode 145 of the second group is electrically connected to the fourth terminal 452, and the third terminal 451 is The fourth terminal 452 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 105a of the first group and the first balanced terminal 211 (first terminal 251) of the first balun 103 are electrically connectable via the blocking capacitor 104a. The blocking capacitor 104a is shielded between the first balanced terminal 211 of the first balun 103 and the first electrode 105a of the first group (or between the first balanced terminal 211 and the second balanced terminal 212 of the first balun 103). Broken DC current. The second electrode 105b of the first group and the second balanced terminal 212 (second terminal 252) of the first balun 103 are electrically connectable via the blocking capacitor 104b. The blocking capacitor 104b is shielded between the second balanced terminal 212 of the first balun 103 and the second electrode 105b of the first group (or between the first balanced terminal 211 and the second balanced terminal 212 of the first balun 103). Broken DC current. The first electrode 105a and the second electrode 105b of the first group are supported by the vacuum vessel 110 via the insulators 132a and 132b, respectively.

The first electrode 141 of the second group and the first balanced terminal 411 (third terminal 451) of the second balun 303 are electrically connectable via the blocking capacitor 304. The blocking capacitor 304 is shielded between the first balanced terminal 411 of the second balun 303 and the first electrode 141 of the second group (or between the first balanced terminal 411 and the second balanced terminal 412 of the second balun 303). Broken DC current. Instead of the blocking capacitor 304, the second impedance matching circuit 302 may block the 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 group are supported by the vacuum vessel 110 via the insulators 142 and 146, respectively.

The plasma processing apparatus 1 may include a first high-frequency power source 101 and a first impedance matching circuit 102 disposed between the first high-frequency power source 101 and the first balun 103. The first high-frequency power source 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 source 101 supplies a high frequency to 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 group constitute a first high-frequency supply unit that supplies a high frequency to the internal space of the vacuum container 110.

The plasma processing apparatus 1 may include a second high frequency power supply 301 and a second impedance matching circuit 302 disposed between the second high frequency power supply 301 and the second balun 303. The second high-frequency power source 301 is supplied between the first unbalanced terminal 401 and the second unbalanced terminal 402 whose frequency is supplied to the second balun 303 via the second impedance matching circuit 302. The second high-frequency power source 301 supplies the high frequency to the first electrode 141 and the second electrode 145 of the second group via the second impedance matching circuit 302, the second balun 303, and the blocking capacitor 304. Alternatively, the second high-frequency power source 301 supplies a high frequency to 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 group constitute a second high-frequency supply unit that supplies a high frequency to the internal space of the vacuum container 110.

By the supply of the high frequency power from the first high frequency power supply 101, the plasma is generated in the internal space of the vacuum container 110, and the first balanced terminal 211 and the second balanced terminal 212 of the first balun 103 are provided. When the first electrode 105a of the first group and the side of the second electrode 105b (the side of the body 10) are viewed, the impedance is Rp1-jXp1. Further, the reactance component (inductance component) of the impedance of the first coil 221 of the first balun 103 is set to X1. In this definition, conforming to 1.5 ≦X1/Rp1≦5000 is advantageous for stabilizing the potential of the plasma formed in the internal space of the vacuum vessel 110.

In addition, in the state where the plasma is generated in the internal space of the vacuum container 110 by the high frequency supply from the second high frequency power supply 301, the first balanced terminal 411 and the second balanced terminal 412 of the second balun 303 are placed. The impedance when the first electrode 127 of the second group and the side of the second electrode 130 (the side of the body 10) are viewed from the side is Rp2-jXp2. Further, the reactance component (inductance component) of the impedance of the first coil 221 of the second balun 303 is set to X2. In this definition, conforming to 1.5 ≦ X2 / Rp2 ≦ 5000 is advantageous for stabilizing the potential of the plasma formed in the internal space of the vacuum vessel 110.

In the plasma processing apparatus 1 of the seventh embodiment, at least one of a mechanism for moving up and down the first electrode 141 constituting the second group and a mechanism for rotating the first electrode 141 constituting the second group can be further provided. In the example shown in FIG. 13 , the plasma processing apparatus 1 is provided with a drive mechanism 114 including both a mechanism for moving the first electrode 141 up and down and a mechanism for rotating the first electrode 141 . Further, in the example shown in FIG. 13, the plasma processing apparatus 1 is provided with a drive mechanism 314 that raises and lowers the second electrode 145 constituting the second group. A bellows constituting a vacuum partition wall may be provided between the vacuum vessel 110 and the drive mechanisms 114, 314.

The function of the first balun 103 of the plasma processing apparatus 1 of the seventh embodiment shown in Fig. 13 will be described with reference to Fig. 14 . The current flowing through the first unbalanced terminal 201 is I1, the current flowing through the first balanced terminal 211 is I2, and the current flowing through the second unbalanced terminal 202 is I2', and the current flows in the current I2. The current to ground is set to I3. I3 = 0, that is, the balance circuit is optimal for the isolation performance of the ground when the side current of the balancing circuit does not flow to the ground. I3=I2, that is, when all of the current I2 flowing through the first balanced terminal 211 flows to the ground, the isolation circuit has the worst isolation performance for the ground. The index ISO indicating the degree of the isolation performance is the same as the first to fifth embodiments, and the following expression can be given. Under this definition, the absolute value of the ISO value is larger and the isolation performance is better. ISO[dB]=20log(I3/I2’)

In FIG. 14, Rp-jXp (=Rp/2-jXp/2+Rp/2-jXp/2) is a state in which plasma is generated in the internal space of the vacuum vessel 110, and the first balanced terminal 211 and the first 2 The impedance of the side of the first electrode 105a and the second electrode 105b (the side of the body 10) when the side of the balanced terminal 212 is viewed (including the reactance of the blocking capacitors 104a and 104b). Rp represents a resistance component, and -Xp represents a reactance component. Further, in FIG. 14, X is a reactance component (inductance component) indicating the impedance of the first coil 221 of the first balun 103. ISO is relevant for X/Rp.

Fig. 4 referred to in the description of the first embodiment is a diagram showing the relationship between the currents I1 (= I2), I2', I3, ISO, and α (= X / Rp). The relationship of Fig. 4 is also true in the seventh embodiment. The present inventors have found that in the seventh embodiment, 1.5 ≦ X / Rp ≦ 5000 is also advantageous in order to facilitate the internal space (the space between the first electrode 105a and the second electrode 105b) to be formed in the vacuum container 110. The potential of the plasma (plasma potential) forms an insensitive feeling with respect to the state of the inner surface of the vacuum vessel 110. Here, the fact that the plasma potential forms an insensitive feeling with respect to the state of the inner surface of the vacuum vessel 110 means that even if the plasma processing apparatus 1 is used for a long period of time, the plasma potential can be stabilized. 1.5≦X/Rp≦5000 is equivalent to -10.0dB≧ISO≧-80dB.

Figs. 15A to 15D show the plasma potential when 1.5 ≦ X / Rp ≦ 5000 is satisfied, the potential of the first electrode 105a (the potential of the cathode 1), and the potential of the second electrode 105b (the potential of the cathode 2). 15A is a plasma potential in a state in which a resistive film (1 mΩ) is formed on the inner surface of the vacuum vessel 110, a potential of the first electrode 105a (potential 1 potential), and a potential of the second electrode 105b (cathode 2 potential). . 15B is a plasma potential in a state in which a resistive film (1000 Ω) is formed on the inner surface of the vacuum vessel 110, a potential of the first electrode 105a (potential 1 potential), and a potential of the second electrode 105b (cathode 2 potential). . 15C is a plasma potential in a state in which an inductive film (0.6 μH) is formed on the inner surface of the vacuum vessel 110, a potential of the first electrode 105a (potential 1 potential), and a potential of the second electrode 105b (cathode 2 potential). ). 15D is a plasma potential in a state in which a capacitive film (0.1 nF) is formed on the inner surface of the vacuum vessel 110, a potential of the first electrode 105a (potential 1 potential), and a potential of the second electrode 105b (cathode 2 potential). ). As can be understood from Figs. 15A to 15D, conforming to 1.5 ≦ X / Rp ≦ 5000 is advantageous for the inner surface of the vacuum vessel 110 to stabilize the plasma potential in various states.

16A to 16D show the results of the plasma potential when the simulation does not conform to 1.5≦X/Rp≦5000, the potential of the first electrode 105a (the potential of the cathode 1), and the potential of the second electrode 105b (the potential of the cathode 2). 16A is a plasma potential in a state in which a resistive film (1 mΩ) is formed on the inner surface of the vacuum vessel 110, a potential of the first electrode 105a (potential 1 potential), and a potential of the second electrode 105b (cathode 2 potential). . 16B is a plasma potential in a state in which a resistive film (1000 Ω) is formed on the inner surface of the vacuum vessel 110, a potential of the first electrode 105a (potential 1 potential), and a potential of the second electrode 105b (cathode 2 potential). . 16C is a plasma potential in a state in which an inductive film (0.6 μH) is formed on the inner surface of the vacuum vessel 110, a potential of the first electrode 105a (potential 1 potential), and a potential of the second electrode 105b (cathode 2 potential). ). 16D is a plasma potential in a state in which a capacitive film (0.1 nF) is formed on the inner surface of the vacuum vessel 110, a potential of the first electrode 105a (potential 1 potential), and a potential of the second electrode 105b (cathode 2 potential). ). As can be understood from FIGS. 16A to 16D, when 1.5 ≦X/Rp ≦ 5000 is not satisfied, the plasma potential changes depending on the state of the inner surface of the vacuum vessel 110.

Here, in the case of X/Rp>5000 (for example, X/Rp=∞) and the case of X/Rp<1.5 (for example, X/Rp=1.16, X/Rp=0.87), the plasma potential is easily dependent. The state of the inner surface of the vacuum vessel 110 changes. In the case where X/Rp>5000, the film is not formed on the inner surface of the vacuum vessel 110, and discharge occurs only between the first electrode 105a and the second electrode 105b. However, in the case of X/Rp &gt; 5000, once the film is formed on the inner surface of the vacuum vessel 110, the plasma potential is sensitively reacted thereto, and the results are as exemplified in Figs. 16A to 16D. On the other hand, in the case of X/Rp<1.5, since the current flowing into the ground via the vacuum vessel 110 is large, the state of the inner surface of the vacuum vessel 110 (the electrical characteristics of the film formed on the inner surface) is caused. The effect is significant and the plasma potential will vary depending on the formation of the film. Therefore, as described above, it is advantageous to configure the plasma processing apparatus 1 so as to conform to 1.5 ≦ X / Rp ≦ 5000.

Fig. 17 is a view schematically showing the configuration of a plasma processing apparatus 1 according to an eighth embodiment of the present invention. The plasma processing apparatus 1 of the eighth embodiment is a modification of the plasma processing apparatus 1 of the second embodiment, and can be operated as an etching apparatus for etching the substrate 112.

The plasma processing apparatus 1 of the eighth embodiment may include a first balun (first balance unbalanced conversion circuit) 103, a second balun (second balance unbalanced conversion circuit) 603, a vacuum container 110, and a first The electrode 106, the second electrode 111, and the third electrode 606. Alternatively, the plasma processing apparatus 1 may include a first balun 103, a second balun 603, and a body 10. The main body 10 includes a vacuum vessel 110, a first electrode 106, a second electrode 111, and a third electrode. 606. The main body 10 has a first terminal 251, a second terminal 252, a third terminal 651, and a fourth terminal 652. The first electrode 106 may be disposed to separate the vacuum space from the external space (that is, a part constituting the vacuum partition) together with the vacuum container 110, or may be disposed in the vacuum container 110. The second electrode 111 may be disposed to separate the vacuum space from the external space (that is, a part constituting the vacuum partition) together with the vacuum container 110, or may be disposed in the vacuum container 110. The third electrode 606 may be disposed to separate the vacuum space from the external space (that is, a part of the vacuum partition) together with the vacuum container 110, or may be disposed in the vacuum container 110.

The first balun 103 has a first unbalanced terminal 201, a second unbalanced terminal 202, a first balanced terminal 211, and a second balanced terminal 212. On the side of the first unbalanced terminal 201 and the second unbalanced terminal 202 of the first balun 103, an unbalanced circuit is connected, and the side of the first balanced terminal 211 and the second balanced terminal 212 of the first balun 103 is A balanced circuit is connected. The vacuum vessel 110 is made of a conductor and is grounded.

The second balun 603 includes a third unbalanced terminal 601, a fourth unbalanced terminal 602, a third balanced terminal 611, and a fourth balanced terminal 612. On the side of the third unbalanced terminal 601 and the fourth unbalanced terminal 602 of the second balun 603, an unbalanced circuit is connected, and the side of the third balanced terminal 611 and the fourth balanced terminal 612 of the second balun 603 is A balanced circuit is connected. The second balun 603 may have the same configuration as the first balun 013.

The second balun 603 may have a configuration such as that shown in FIG. 2A or a configuration shown in FIG. 2B. Specifically, the second balun 603 has a fifth coil (221) that connects the third unbalanced terminal 601 and the third balanced terminal 611, and a sixth coil that connects the fourth unbalanced terminal 602 and the fourth balanced terminal 612. Coil (222). The fifth coil (221) and the sixth coil (222) are coils of the same number of windings, and have a common core. Alternatively, the second balun 603 includes a fifth coil (221) that connects the third unbalanced terminal 601 and the third balanced terminal 611, and a sixth coil that connects the fourth unbalanced terminal 602 and the fourth balanced terminal 612 (222). And the seventh coil (223) and the eighth coil (224) connected between the third balanced terminal 611 and the fourth balanced terminal 612, and the seventh coil 6 (223) and the eighth coil (224) are The voltage at the connection node (213) of the seventh coil (223) and the eighth coil (224) is set to be the middle of the voltage of the third balanced terminal 611 and the voltage of the fourth balanced terminal 612. The fifth coil (221) and the sixth coil (222) are coils of the same number of windings, and have a common core. The seventh coil (223) and the eighth coil (224) are coils of the same number of turns, and have a core. The connection node (213) may also be grounded, may be connected to the vacuum vessel 110, or may be floated.

In the eighth embodiment, the first electrode 106 is a cathode and holds the substrate 112. Further, in the eighth embodiment, the second electrode 111 is an anode. In the plasma processing apparatus 1 of the eighth embodiment, the first electrode 106 and the first balanced terminal 211 are electrically connected via the blocking capacitor 104. In other words, in the plasma processing apparatus 1 of the eighth embodiment, the blocking capacitor 104 is disposed in an electrical connection path between the first electrode 106 and the first balanced terminal 211. The gas distribution portion 195 including one or a plurality of gas supply holes for distributing a gas containing an etching gas may be incorporated into the second electrode 111.

Instead of the above-described configuration, the second balanced terminal 212 and the second electrode 111 may be electrically connected via a blocking capacitor. Alternatively, the first balanced terminal 211 and the first electrode 106 may be electrically connected via a blocking capacitor, and the second balanced terminal 212 and the second electrode 111 may be electrically connected via a blocking capacitor.

The first electrode 106 and the second electrode 111 are configurable to face each other. In another aspect, the first electrode 106 and the second electrode 111 are disposed so that at least a part of the first electrode 106 and at least a part of the second electrode 111 face each other. The third electrode 606 is configurable to surround the first electrode 106. The third electrode 606 may have a ring shape.

The first electrode 106 may have a shape symmetrical with respect to the axis of symmetry SA, the second electrode 111 may have a shape symmetrical with respect to the axis of symmetry SA, and the third electrode 606 may have a shape symmetrical with respect to the axis of symmetry SA. In one example, the first electrode 106 may have a circular shape symmetrically arranged with respect to the axis of symmetry SA, the second electrode 111 may have a circular shape symmetrically arranged with respect to the axis of symmetry SA, and the third electrode 606 may have a axis of symmetry The ring shape of the SA symmetrically configured. The ring shape may be, for example, a circular ring shape or a rectangular ring shape. The shape of the circular ring is such that the outer edge defines a circular shape, and the inner edge defines a circular shape. The shape of the rectangular ring is such that the shape of the outer edge is a rectangle, and the shape of the inner edge is defined as a rectangle.

The resistance component between the first balanced terminal 211 and the second balanced terminal 212 when the first electrode 106 and the second electrode 111 are viewed from the side of the first balanced terminal 211 and the second balanced terminal 212 is Rp. Further, the inductance between the first unbalanced terminal 201 and the first balanced terminal 211 is X. At this time, conforming to 1.5 ≦ X / Rp ≦ 5000 is advantageous for the potential of the plasma formed in the internal space of the vacuum vessel 110 (the space between the first electrode 106 and the second electrode 111) for the vacuum vessel 110. The state of the inner surface forms a blunt feeling.

Further, the resistance component between the third balanced terminal 611 and the fourth balanced terminal 612 when the first electrode 106 and the third electrode 606 are viewed from the side of the third balanced terminal 611 and the fourth balanced terminal 612 are provided. In the case of Rp', the inductance between the third unbalanced terminal 601 and the third balanced terminal 611 is set to X'. At this time, conforming to 1.5≦X'/Rp'≦5000 is advantageous for the potential of the plasma to be formed in the internal space of the vacuum vessel 110 (the space between the first electrode 106 and the second electrode 111) for the vacuum vessel The state of the inner face of 110 forms a blunt feeling.

Fig. 18 is a view schematically showing the configuration of a plasma processing apparatus 1 according to a ninth embodiment of the present invention. The plasma processing apparatus 1 of the ninth embodiment is a modification of the plasma processing apparatus 1 of the first embodiment, and can be operated as a sputtering apparatus in which a film is formed on the substrate 112 by sputtering.

The plasma processing apparatus 1 of the ninth embodiment may include a first balun (first balance unbalanced conversion circuit) 103, a second balun (second balance unbalanced conversion circuit) 603, a vacuum container 110, and a first The electrode 106, the second electrode 111, and the third electrode 606. Alternatively, the plasma processing apparatus 1 may be configured to include a first balun 103, a second balun 603, and a body 10. The main body 10 includes a vacuum vessel 110, a first electrode 106, a second electrode 111, and a third electrode. 606. The main body 10 has a first terminal 251, a second terminal 252, a third terminal 651, and a fourth terminal 652. The first electrode 106 may be disposed to separate the vacuum space from the external space (that is, a part constituting the vacuum partition) together with the vacuum container 110, or may be disposed in the vacuum container 110. The second electrode 111 may be disposed to separate the vacuum space from the external space (that is, a part constituting the vacuum partition) together with the vacuum container 110, or may be disposed in the vacuum container 110. The third electrode 606 may be disposed to separate the vacuum space from the external space (that is, a part of the vacuum partition) together with the vacuum container 110, or may be disposed in the vacuum container 110.

The first balun 103 has a first unbalanced terminal 201, a second unbalanced terminal 202, a first balanced terminal 211, and a second balanced terminal 212. On the side of the first unbalanced terminal 201 and the second unbalanced terminal 202 of the first balun 103, an unbalanced circuit is connected, and the side of the first balanced terminal 211 and the second balanced terminal 212 of the first balun 103 is A balanced circuit is connected. The vacuum vessel 110 is made of a conductor and is grounded.

The second balun 603 includes a third unbalanced terminal 601, a fourth unbalanced terminal 602, a third balanced terminal 611, and a fourth balanced terminal 612. The side of the third unbalanced terminal 601 and the fourth unbalanced terminal 602 of the second balun 603 is an unbalanced circuit, and is connected to the side of the third balanced terminal 611 and the fourth balanced terminal 612 of the second balun 603. Balance the circuit. The second balun 603 may have the same configuration as the first balun 013.

The second balun 603 may have a configuration such as that shown in FIG. 2A or a configuration shown in FIG. 2B. Specifically, the second balun 603 has a fifth coil (221) that connects the third unbalanced terminal 601 and the third balanced terminal 611, and a sixth coil that connects the fourth unbalanced terminal 602 and the fourth balanced terminal 612. Coil (222). The fifth coil (221) and the sixth coil (222) are coils of the same number of windings, and have a common core. Alternatively, the second balun 603 includes a fifth coil (221) that connects the third unbalanced terminal 601 and the third balanced terminal 611, and a sixth coil that connects the fourth unbalanced terminal 602 and the fourth balanced terminal 612 (222). And the seventh coil (223) and the eighth coil (224) connected between the third balanced terminal 611 and the fourth balanced terminal 612, and the seventh coil (223) and the eighth coil (224) are configured The voltage at the connection node (213) of the seventh coil (223) and the eighth coil (224) is the midpoint of the voltage of the third balanced terminal 611 and the voltage of the fourth balanced terminal 612. The fifth coil (221) and the sixth coil (222) are coils of the same number of windings, and have a common core. The seventh coil (223) and the eighth coil (224) are coils of the same number of turns, and have a core. The connection node (213) may also be grounded, may be connected to the vacuum vessel 110, or may be floated.

In the ninth embodiment, the first electrode 106 is a cathode and holds the target 109. Further, in the ninth embodiment, the second electrode 111 is an anode and holds the substrate 112. In the plasma processing apparatus 1 of the ninth embodiment, the first electrode 106 and the first balanced terminal 211 are electrically connected via the blocking capacitor 104. In other words, in the plasma processing apparatus 1 of the ninth embodiment, the blocking capacitor 104 is disposed in an electrical connection path between the first electrode 106 and the first balanced terminal 211.

Instead of the above-described configuration, the second balanced terminal 212 and the second electrode 111 may be electrically connected via a blocking capacitor. Alternatively, the first balanced terminal 211 and the first electrode 106 may be electrically connected via a blocking capacitor, and the second balanced terminal 212 and the second electrode 111 may be electrically connected via a blocking capacitor.

The first electrode 106 and the second electrode 111 are configurable to face each other. In another aspect, the first electrode 106 and the second electrode 111 are arrangable so that at least a part of the first electrode 106 and at least a part of the second electrode 111 face each other. The third electrode 606 is configurable to surround the first electrode 106. The third electrode 606 may have a ring shape.

The first electrode 106 may have a shape symmetrical with respect to the axis of symmetry SA, the second electrode 111 may have a shape symmetrical with respect to the axis of symmetry SA, and the third electrode 606 may have a shape symmetrical with respect to the axis of symmetry SA. In one example, the first electrode 106 may have a circular shape symmetrically arranged with respect to the axis of symmetry SA, the second electrode 111 may have a circular shape symmetrically arranged with respect to the axis of symmetry SA, and the third electrode 606 may have a axis of symmetry The ring shape of the SA symmetrically configured. The ring shape may be, for example, a circular ring shape or a rectangular ring shape. The shape of the circular ring is such that the outer edge defines a circular shape, and the inner edge defines a circular shape. The shape of the rectangular ring is such that the shape of the outer edge is a rectangle, and the shape of the inner edge is defined as a rectangle.

The present invention is not limited to the embodiments described above, and various modifications and changes can be made without departing from the spirit and scope of the invention. Therefore, in order to disclose the scope of the present invention, the following claims are attached.

1‧‧‧Plastic processing unit

10‧‧‧ Ontology

101‧‧‧High frequency power supply (1st high frequency source)

102‧‧‧ impedance matching circuit (first impedance matching circuit)

103‧‧‧ Barron (1st Barron)

104‧‧‧blocking capacitor

106‧‧‧1st electrode

107, 108‧‧‧Insulators

109‧‧‧ Target

110‧‧‧vacuum container

111‧‧‧2nd electrode

112‧‧‧Substrate

195‧‧‧Gas Distribution Department

201‧‧‧1st unbalanced terminal

202‧‧‧2nd unbalanced terminal

211‧‧‧1st balanced terminal

212‧‧‧2nd balanced terminal

251‧‧‧1st terminal

252‧‧‧2nd terminal

221‧‧‧1st coil

222‧‧‧2nd coil

223‧‧‧3rd coil

224‧‧‧4th coil

SA‧‧ symmetry axis

501‧‧‧High frequency source (2nd high frequency source)

502‧‧‧ impedance matching circuit (2nd impedance matching circuit)

601‧‧‧3rd unbalanced terminal

602‧‧‧4th unbalanced terminal

603‧‧‧ Barron (2nd Barron)

611‧‧‧3rd balanced terminal

612‧‧‧4th balanced terminal

604‧‧‧blocking capacitor

606‧‧‧3rd electrode

FIG. 1 is a view schematically showing a configuration of a plasma processing apparatus 1 according to a first embodiment of the present invention. Fig. 2A is a view showing a configuration example of a balun. Fig. 2B is a view showing another configuration example of the balun. FIG. 3 is a diagram illustrating the function of the balun 103. Fig. 4 is a view exemplifying the relationship between currents I1 (= I2), I2', I3, ISO, and α (= X / Rp). Fig. 5A is a graph showing the results of simulating the plasma potential and the cathode potential when 1.5 ≦ X / Rp ≦ 5000 is satisfied. Fig. 5B is a graph showing the results of simulating the plasma potential and the cathode potential when 1.5 ≦ X / Rp ≦ 5000 is satisfied. Fig. 5C is a graph showing the results of simulating the plasma potential and the cathode potential when 1.5 ≦ X / Rp ≦ 5000 is satisfied. Fig. 5D is a graph showing the results of simulation of plasma potential and cathode potential when 1.5 ≦ X / Rp ≦ 5000 is satisfied. Fig. 6A is a graph showing the results of simulating plasma potential and cathode potential when 1.5 ≦ X / Rp ≦ 5000 is not satisfied. Fig. 6B is a graph showing the results of simulating the plasma potential and the cathode potential when 1.5 ≦ X / Rp ≦ 5000 is not satisfied. Fig. 6C is a graph showing the results of simulating the plasma potential and the cathode potential when 1.5 ≦ X / Rp ≦ 5000 is not satisfied. Fig. 6D is a graph showing the results of simulating the plasma potential and the cathode potential when 1.5 ≦ X / Rp ≦ 5000 is not satisfied. FIG. 7 is a diagram illustrating a method of confirming Rp-jXp. FIG. 8 is a view schematically showing a configuration of a plasma processing apparatus 1 according to a second embodiment of the present invention. FIG. 9 is a view schematically showing a configuration of a plasma processing apparatus 1 according to a third embodiment of the present invention. FIG. 10 is a view schematically showing a configuration of a plasma processing apparatus 1 according to a fourth embodiment of the present invention. Fig. 11 is a view schematically showing a configuration of a plasma processing apparatus 1 according to a fifth embodiment of the present invention. Fig. 12 is a view schematically showing a configuration of a plasma processing apparatus 1 according to a sixth embodiment of the present invention. FIG. 13 is a view schematically showing a configuration of a plasma processing apparatus 1 according to a seventh embodiment of the present invention. Fig. 14 is a view for explaining the function of a balun in the sixth embodiment of the present invention. Fig. 15A is a graph showing the results of simulating the plasma potential and the cathode potential of two 符合X/Rp ≦5000. Fig. 15B is a graph showing the results of simulating the plasma potential and the cathode potential of two 符合X/Rp ≦5000. Fig. 15C is a graph showing the results of simulating the plasma potential and the cathode potential of two 符合X/Rp ≦5000. Fig. 15D is a graph showing the results of simulating the plasma potential and the cathode potentials at 1.5 ≦ X / Rp ≦ 5000. Fig. 16A is a graph showing the results of simulating the plasma potential and the cathode potentials of two 不X/Rp ≦5000. Fig. 16B is a graph showing the results of simulating the plasma potential and the cathode potential of two 不X/Rp ≦5000. Fig. 16C is a graph showing the results of simulating the plasma potential and the cathode potential of two 不X/Rp ≦5000. Fig. 16D is a graph showing the results of simulating the plasma potential and the cathode potential of two 不X/Rp ≦5000. FIG. 17 is a view schematically showing a configuration of a plasma processing apparatus 1 according to an eighth embodiment of the present invention. FIG. 18 is a view schematically showing a configuration of a plasma processing apparatus 1 according to a ninth embodiment of the present invention.

Claims (20)

A plasma processing apparatus characterized by comprising: a first balun having a first unbalanced terminal, a second unbalanced terminal, a first balanced terminal, and a second balanced terminal; and a third unbalanced terminal and a fourth unbalanced a second balun of the terminal, the third balanced terminal, and the fourth balanced terminal; a vacuum container that is grounded; a first electrode electrically connected to the first balanced terminal and the third balanced terminal; and electrically connected to the first a second electrode of the balanced terminal; and a third electrode electrically connected to the fourth balanced terminal. The plasma processing apparatus according to claim 1, wherein the first electrode and the second electrode are disposed to face each other. The plasma processing apparatus according to claim 1, wherein the third electrode is disposed to surround the first electrode. A plasma processing apparatus according to claim 3, wherein the third electrode has a ring shape. The plasma processing apparatus according to claim 1, wherein the first electrode has a shape that is symmetrical about an axis of symmetry, and the second electrode has a shape that is symmetrical about the axis of symmetry, and the third electrode is It has a shape that is symmetrical about the aforementioned axis of symmetry. The plasma processing apparatus according to claim 1, wherein the first balanced terminal and the first electrode are electrically connected via a blocking capacitor. The plasma processing apparatus according to claim 1, wherein the third balanced terminal and the first electrode are electrically connected via a blocking capacitor. 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 third balanced terminal and the first electrode are electrically connected via a blocking capacitor. . The plasma processing apparatus according to claim 1, wherein the first electrode, the second electrode, and the third electrode are supported by the vacuum container via an insulator. The plasma processing apparatus according to claim 1, wherein the first balun has a first coil that connects the first unbalanced terminal and the first balanced terminal, and a second unbalanced terminal The second coil of the second balanced terminal. The plasma processing apparatus according to claim 10, wherein the first balun further includes: a third coil and a fourth coil connected between the first balanced terminal and the second balanced terminal; The third coil and the fourth coil are configured such that a voltage at a connection node between the third coil and the fourth coil is a midpoint between a voltage of the first balanced terminal and a voltage of the second balanced terminal. The plasma processing apparatus according to claim 1, wherein the second balun has a fifth coil that connects the third unbalanced terminal and the third balanced terminal, and a fourth unbalanced terminal The sixth coil of the fourth balanced terminal. The plasma processing apparatus according to claim 12, wherein the second balun further includes a seventh coil and an eighth coil connected between the third balanced terminal and the fourth balanced terminal, The seventh coil and the eighth coil are configured such that a voltage at a connection node between the seventh coil and the eighth coil is a midpoint between a voltage of the third balanced terminal and a voltage of the fourth balanced terminal. The plasma processing apparatus according to claim 1, wherein the first electrode is a holding substrate, and the plasma processing device is an etching device that etches the substrate. The plasma processing apparatus of claim 14, wherein the second electrode is a gas distribution unit that distributes a gas. The plasma processing apparatus according to claim 1, wherein the first electrode is a target, the second electrode is a substrate, and the plasma processing device is configured to form a film by sputtering. A sputtering apparatus for the above substrate. The plasma processing apparatus according to claim 1, further comprising: a first high frequency power supply; a first impedance matching circuit disposed between the first high frequency power source and the first balun; a frequency power source; and a second impedance matching circuit disposed between the second high frequency power source and the second balun. The plasma processing apparatus according to the first aspect of the invention, wherein the first balanced terminal when the first electrode and the second electrode are viewed from a side of the first balanced terminal and the second balanced terminal The resistance component between the second balanced terminal and the second balanced terminal is Rp, and when the inductance between the first unbalanced terminal and the first balanced terminal is X, it corresponds to 1.5≦X/Rp≦5000. The plasma processing apparatus according to the first aspect of the invention, wherein the third balanced terminal when the first electrode and the third electrode are viewed from a side of the third balanced terminal and the fourth balanced terminal The resistance component between the fourth balanced terminal and the fourth balanced terminal is Rp', and when the inductance between the third unbalanced terminal and the third balanced terminal is X', it corresponds to 1.5≦X'/Rp'≦5000. . The plasma processing apparatus according to the first aspect of the invention, wherein the first balanced terminal when the first electrode and the second electrode are viewed from a side of the first balanced terminal and the second balanced terminal The resistance component between the second balanced terminal and the second balanced terminal is Rp, and when the inductance between the first unbalanced terminal and the first balanced terminal is X, 1.5符合X/Rp≦5000 is satisfied, and the When the side of the third balanced terminal and the fourth balanced terminal is viewed from the side of the first electrode and the third electrode, the resistance component between the third balanced terminal and the fourth balanced terminal is Rp', and When the inductance between the third unbalanced terminal and the third balanced terminal is X', it corresponds to 1.5≦X'/Rp'≦5000.