Plasma Processing Equipment

Abstract

To independently control the ratio of ions to radicals at the center and edges of an object to be processed.SOLUTION: A plasma processing apparatus includes: a processing container in which a mounting table having a mounting surface on which an object to be processed is placed is provided and plasma processing is performed; a dielectric having a facing surface facing the mounting surface of the mounting table; an antenna provided on the surface opposite to the facing surface of the dielectric and generating plasma by introducing an induced electric field through the dielectric; a first electromagnet group provided on the outer periphery of the processing container at a position higher than the mounting surface of the mounting table and forming a first magnetic field above the mounting surface of the mounting table; a second electromagnet group provided inside the mounting table; and a third electromagnet group provided at a position corresponding to the second electromagnet group on the outer circumference of the processing container and forming a second magnetic field around the mounting surface of the mounting table.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a plasma processing apparatus. [Background technology]

[0002] 2. Description of the Related Art There are plasma processing apparatuses that perform plasma processing on a workpiece such as a semiconductor wafer by utilizing plasma excitation by an inductive electric field. Such plasma processing apparatuses are called inductively coupled plasma processing apparatuses.

[0003] Patent Document 1 discloses an inductively coupled plasma processing apparatus in which a group of electromagnets is provided along the outer periphery of a processing vessel that contains an object to be processed, and a magnetic field that crosses the plasma within the processing vessel and a magnetic field that surrounds the plasma are formed, thereby reducing the amount of ions that reach the object to be processed. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2018-98094 A Summary of the Invention [Problem to be solved by the invention]

[0005] The present disclosure provides a technique that can independently control the ratio of ions to radicals at the center and edge of a processing object. [Means for solving the problem]

[0006] A plasma processing apparatus according to one embodiment of the present disclosure includes a processing vessel having a mounting table having a mounting surface on which a workpiece is placed, and in which plasma processing is performed on the workpiece; a dielectric having a facing surface facing the mounting surface of the mounting table; an antenna provided on the surface opposite to the facing surface of the dielectric, and generating plasma by introducing an induced electric field into the processing vessel via the dielectric; a first group of electromagnets provided on the outer periphery of the processing vessel at a position higher than the mounting surface of the mounting table and forming a first magnetic field that crosses the processing vessel above the mounting surface of the mounting table; a second group of electromagnets provided inside the mounting table along the outer periphery of the mounting table; and a third group of electromagnets provided on the outer periphery of the processing vessel at a position corresponding to the second group of electromagnets and cooperating with the second group of electromagnets to form a second magnetic field around the mounting surface of the mounting table. Effect of the Invention

[0007] The present disclosure provides an advantage in that the ratio of ions to radicals at the center and edge of a processing object can be controlled independently. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a cross-sectional view showing a schematic configuration of a plasma processing apparatus according to this embodiment. [Diagram 2] FIG. 2 is a horizontal cross-sectional view that illustrates a first electromagnet group according to the present embodiment. [Diagram 3] FIG. 3 is a horizontal cross-sectional view that illustrates the second electromagnet group and the third electromagnet group according to the present embodiment. [Figure 4] FIG. 4 is a diagram for explaining the movement of the third electromagnet group according to the present embodiment. [Diagram 5] FIG. 5 is a diagram showing an example of the first magnetic field formed in each area. [Figure 6] FIG. 6 is a diagram showing another example of the first magnetic field formed for each area. [Figure 7] FIG. 7 is a diagram showing an example of the second magnetic field formed in each area. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, an embodiment of the plasma processing apparatus disclosed in the present application will be described in detail with reference to the drawings. Note that the same or corresponding parts in each drawing will be denoted by the same reference numerals. Also, the processing apparatus disclosed is not limited to the present embodiment.

[0010] However, in an inductively coupled plasma processing apparatus in which a group of electromagnets is provided along the outer periphery of a processing vessel, there is room for improvement in terms of independently controlling the ratio of ions to radicals at the center and edge of an object to be processed.

[0011] It is therefore anticipated that the ratio of ions to radicals at the center and edge of the workpiece will be controlled independently.

[0012] (Configuration example of plasma processing apparatus) First, a configuration example of a plasma processing apparatus 100 according to this embodiment will be described with reference to the drawings. Here, an inductively coupled plasma processing apparatus is taken as an example, which performs a predetermined plasma processing on a semiconductor wafer (hereinafter also simply referred to as a "wafer") W, which is an object to be processed, by using plasma of a processing gas excited in a processing container by applying high frequency power to a planar high frequency antenna. Fig. 1 is a cross-sectional view showing a schematic configuration of the plasma processing apparatus 100 according to this embodiment.

[0013] 1, the plasma processing apparatus 100 includes a processing vessel (chamber) 102 made of metal (e.g., aluminum) and formed in a tubular (e.g., cylindrical) shape. Note that the shape of the processing vessel 102 is not limited to a cylindrical shape. For example, it may be a rectangular tubular shape (e.g., a box shape).

[0014] A mounting table 110 for mounting a wafer W thereon is provided at the bottom of the processing vessel 102. The mounting table 110 is made of aluminum or the like and has a generally columnar (e.g., cylindrical) shape. The upper surface of the mounting table 110 serves as a mounting surface 110a on which the wafer W is mounted. The shape of the mounting table 110 is not limited to a cylindrical shape. For example, it may be a prismatic (e.g., polygonal) shape. Although not shown, the mounting table 110 may be provided with various functions as necessary, such as an electrostatic chuck that attracts and holds the wafer W by Coulomb force, and a temperature adjustment mechanism such as a heater and a coolant flow path.

[0015] A plate-shaped dielectric 104 made of, for example, quartz glass or ceramic is provided on the ceiling of the processing vessel 102 so as to face the mounting table 110. Specifically, the dielectric 104 is formed, for example, in a disk shape, and is airtightly attached so as to cover an opening formed in the ceiling of the processing vessel 102. The dielectric 104 has an opposing surface 104a facing the mounting surface 110a of the mounting table 110.

[0016] The processing vessel 102 is provided with a gas supply unit 120 that supplies a processing gas for processing the wafer W. The gas supply unit 120 is configured, for example, as shown in FIG. 1. That is, a gas inlet 121 is formed in a sidewall of the processing vessel 102, and a gas supply source 122 is connected to the gas inlet 121 via a gas supply pipe 123. A flow rate controller for controlling the flow rate of the processing gas, such as a mass flow controller 124 and an opening / closing valve 126, is provided in the gas supply pipe 123. According to the gas supply unit 120, the processing gas from the gas supply source 122 is controlled to a predetermined flow rate by the mass flow controller (MFC) 124 and supplied into the processing vessel 102 from the gas inlet 121.

[0017] In FIG. 1, for the sake of simplicity, the gas supply unit 120 is represented by a single gas line system. However, the gas supply unit 120 is not limited to supplying a single type of processing gas, and may supply multiple types of gas as processing gas. In this case, multiple gas supply sources may be provided to configure multiple gas lines, and each gas line may be provided with a mass flow controller. In addition, FIG. 1 shows an example in which the gas supply unit 120 is configured to supply gas from the side wall of the processing vessel 102, but this is not necessarily limited to this. For example, the gas may be configured to supply gas from the ceiling of the processing vessel 102. In this case, a gas inlet may be formed, for example, in the center of the dielectric 104, and gas may be supplied from there.

[0018] The processing gas supplied into the processing vessel 102 by the gas supply unit 120 is, for example, a fluorocarbon gas containing C and F when etching an oxide film. Specifically, when etching a silicon oxide film such as a SiO2 film, CHF3 gas or the like is used as the processing gas. When etching a high dielectric thin film such as HfO2, HfSiO2, ZrO2, or ZrSiO4, BCl3 gas or a mixed gas of BCl3 gas and O2 gas is used as the processing gas.

[0019] An exhaust unit 130 that exhausts the atmosphere inside the processing vessel 102 is connected to the bottom of the processing vessel 102 via an exhaust pipe 132. The exhaust unit 130 is configured, for example, by a vacuum pump, and is capable of reducing the pressure inside the processing vessel 102 to a predetermined level. A wafer loading / unloading port 134 is formed in the sidewall of the processing vessel 102, and a gate valve 136 is provided at the wafer loading / unloading port 134. For example, when loading a wafer W, the gate valve 136 is opened and the wafer W is placed on the mounting table 110 in the processing vessel 102 by a transfer mechanism such as a transfer arm (not shown), and the gate valve 136 is closed to process the wafer W.

[0020] A planar radio frequency antenna 140 is disposed on a surface 104b opposite to the facing surface 104a of the dielectric 104. The radio frequency antenna 140 introduces an induction electric field for plasma excitation into the processing vessel 102 via the dielectric 104. The radio frequency antenna 140 is configured by sandwiching a spiral antenna element 142 made of a conductor such as copper, aluminum, or stainless steel between a plurality of sandwiching bodies 144.

[0021] A high frequency power supply 150 is connected to the antenna element 142. The high frequency power supply 150 supplies high frequency power of a predetermined frequency (for example, 27.12 MHz) to the antenna element 142. Then, an induction electric field is introduced into the processing vessel 102 via the dielectric 104 by the antenna element 142 to which the high frequency power is supplied. Then, the gas introduced into the processing vessel 102 is excited by the induction electric field introduced into the processing vessel 102, and plasma is generated. In this way, a predetermined plasma process such as an ashing process, an etching process, or a film formation process is performed on the wafer W. The high frequency power output from the high frequency power supply 150 is not limited to 27.12 MHz. For example, it may be 13.56 MHz, 60 MHz, or the like. However, it is necessary to adjust the electrical length of the antenna element 142 according to the high frequency power output from the high frequency power supply 150.

[0022] The height of the high frequency antenna 140 can be adjusted by an actuator 148 .

[0023] A shield member 160 having a substantially tubular (e.g., cylindrical) shape is provided on the ceiling of the processing vessel 102 so as to cover the high frequency antenna 140. The shape of the shield member 160 is not limited to a cylindrical shape. The shape of the shield member 160 may be other shapes such as a rectangular cylindrical shape, but it is preferable to match the shape of the processing vessel 102. Here, for example, since the processing vessel 102 is substantially cylindrical, the shield member 160 is also formed to be substantially cylindrical. If the processing vessel 102 is substantially rectangular cylindrical, it is preferable that the shield member 160 is also substantially rectangular cylindrical. The height of the shield member 160 can be adjusted by an actuator 168.

[0024] A first electromagnet group 170 is provided on the outer periphery of the processing vessel 102. For example, the first electromagnet group 170 is provided on the outer surface of the sidewall of the processing vessel 102 in a concentric manner around the central axis of the processing vessel 102 and the mounting table 110. The first electromagnet group 170 is provided on the outer surface of the sidewall of the processing vessel 102 so as to be at a position higher than the mounting surface 110a of the mounting table 110. The first electromagnet group 170 forms a magnetic field that crosses the plasma above the mounting surface 110a of the mounting table 110. The configuration of the first electromagnet group 170 will be described later.

[0025] A second electromagnet group 180 is provided inside the mounting table 110 in the processing vessel 102. In this embodiment, a hollow internal space 110b that is not exposed to the inside of the processing vessel 102 is formed in the mounting table 110. The second electromagnet group 180 is provided on the inner wall surface of the internal space 110b along the outer periphery of the mounting table 110. For example, the second electromagnet group 180 is provided on the inner wall surface of the internal space 110b in a concentric shape centered on the central axis of the processing vessel 102 and the mounting table 110. The second electromagnet group 180 is provided inside the mounting table 110 (i.e., on the inner wall surface of the internal space 110b), and is therefore located at a lower position than the mounting surface 110a of the mounting table 110.

[0026] A third electromagnet group 190 is provided on the outer periphery of the processing vessel 102. For example, the third electromagnet group 190 is provided on the outer surface of the sidewall of the processing vessel 102 in a concentric manner around the central axis of the processing vessel 102 and the mounting table 110. The third electromagnet group 190 is provided on the outer surface of the sidewall of the processing vessel 102 so as to be at a position corresponding to the second electromagnet group 180. In this embodiment, the third electromagnet group 190 is provided on the outer surface of the sidewall of the processing vessel 102 so as to be at the same height position as the second electromagnet group 180. The third electromagnet group 190 may be provided at a higher position than the same height position as the second electromagnet group 180. The third electromagnet group 190 cooperates with the second electromagnet group 180 to form a magnetic field around the mounting surface 110a of the mounting table. The configurations of the second electromagnet group 180 and the third electromagnet group 190 will be described later.

[0027] A control unit 200 having a CPU is connected to the plasma processing apparatus 100, and each unit of the plasma processing apparatus 100 is controlled by the control unit 200. In addition, an operation unit 210 including a keyboard for an operator to input commands to manage the plasma processing apparatus 100, a display that visualizes and displays the operating status of the plasma processing apparatus 100, and the like are connected to the control unit 200.

[0028] Furthermore, the control unit 200 is connected to a memory unit 220 that stores programs for implementing various processes performed in the plasma processing apparatus 100 under the control of the control unit 200, recipe data required to execute the programs, and the like.

[0029] The storage unit 220 stores, for example, a plurality of process recipes for performing process processing of the wafer W, as well as recipes for performing necessary processing such as cleaning processing inside the processing vessel 102. The recipes are data that compile a plurality of parameter values ​​such as control parameters and setting parameters for controlling each part of the plasma processing apparatus 100. For example, the process recipe has parameter values ​​such as the flow rate ratio of the processing gas, the pressure inside the processing vessel, and the high frequency power.

[0030] The recipe may be stored in a hard disk or semiconductor memory, or may be stored on a portable computer-readable storage medium such as a CD-ROM or DVD and set in a predetermined position in the storage unit 220.

[0031] The control unit 200 reads out a desired process recipe from the storage unit 220 based on instructions from the operation unit 210 and controls each unit to execute a desired process in the plasma processing apparatus 100. In addition, the recipe can be edited by operating the operation unit 210.

[0032] (Configuration of the first electromagnet group) Next, the configuration of the first electromagnet group 170 will be described with reference to FIG. 2. FIG. 2 is a horizontal cross-sectional view that typically illustrates the first electromagnet group 170 according to this embodiment. The cross-section illustrated in FIG. 2 corresponds to a horizontal cross-section of the mounting table 110 in the processing vessel 102 as viewed from above. FIG. 2 illustrates a disk-shaped mounting surface 110a of the mounting table 110, and also illustrates a wafer W mounted on the mounting surface 110a of the mounting table 110. The first electromagnet group 170 is provided at a position higher than the mounting surface 110a of the mounting table 110 on the outer periphery of the processing vessel 102.

[0033] The first electromagnet group 170 includes a plurality of electromagnets 171 arranged concentrically (in a ring shape) around the central axis of the processing vessel 102 and the mounting table 110. In the example of FIG. 2, 16 electromagnets 171 are arranged in a ring shape. The electromagnets 171 arranged in two zones divided in the circumferential direction of the first electromagnet group 170 have different magnetic pole orientations. That is, the magnetic poles of the electromagnets 171 are set so that the magnetic pole orientation of the electromagnets 171 arranged in one of the two zones divided in the circumferential direction of the first electromagnet group 170 and the magnetic pole orientation of the electromagnets 171 arranged in the other zone are opposite to each other. In the example of FIG. 2, the first electromagnet group 170 is divided into a left zone and a right zone in the circumferential direction, and the magnetic pole orientation of the eight electromagnets 171 arranged in the left zone and the magnetic pole orientation of the eight electromagnets 171 arranged in the right zone are opposite to each other. 2, the first electromagnet group 170 forms a magnetic field across the processing vessel 102 above the mounting surface 110a of the mounting table 110. The magnetic field formed by the first electromagnet group 170 is hereinafter referred to as a "first magnetic field."

[0034] In the plasma processing apparatus 100, a first magnetic field is formed by the first electromagnet group 170 while plasma is generated in the processing vessel 102 by the induced electric field from the antenna element 142. The first magnetic field is a horizontal magnetic field that crosses the plasma generated in the processing vessel 102. When the first magnetic field is formed in the processing vessel 102, electrons in the plasma are wound around the magnetic field lines of the first magnetic field, which is a horizontal magnetic field, and move back and forth along the magnetic flux lines. In addition, the higher the magnetic flux density, the smaller the Larmor radius, so that the electron density at the height of the magnet where the magnetic flux density is high is high, and the electron density in the periphery (above and below the center of the magnet) is low. In addition, since positive ions in the plasma are attracted to electrons to maintain electrical neutrality, the density of positive ions in the height direction is also highest at the center height of the magnet. The first magnetic field crosses the plasma generated in the processing vessel 102, thereby capturing ions (e.g., positive ions) in the plasma located above the mounting surface 110a of the mounting table 110. This reduces the amount of ions reaching the wafer W at both the center and edge of the wafer W on the mounting surface 110a of the mounting table 110. On the other hand, electrically neutral radicals in the plasma pass through the first magnetic field and fall toward the wafer W on the mounting surface 110a of the mounting table 110.

[0035] (Configuration of the second electromagnet group and the third electromagnet group) Next, the configurations of the second electromagnet group 180 and the third electromagnet group 190 will be described with reference to FIG. 3. FIG. 3 is a horizontal cross-sectional view that illustrates the second electromagnet group 180 and the third electromagnet group 190 according to the present embodiment. The cross-section illustrated in FIG. 3 corresponds to a horizontal cross-section of the mounting table 110 in the processing vessel 102 as viewed from above. FIG. 3 illustrates a disk-shaped mounting surface 110a of the mounting table 110 and a wafer W mounted on the mounting surface 110a of the mounting table 110. The second electromagnet group 180 is provided inside the mounting table 110 along the outer periphery of the mounting table 110, and the third electromagnet group 190 is provided at the same height as the second electromagnet group 180 on the outer periphery of the processing vessel 102.

[0036] The second electromagnet group 180 includes a plurality of electromagnets 181 arranged concentrically (in a ring shape) around the central axes of the processing vessel 102 and the mounting table 110. In the example of Fig. 3, 16 electromagnets 181 are arranged in a ring shape.

[0037] The third electromagnet group 190 includes a plurality of electromagnets 191 arranged concentrically (in a ring shape) around the central axis of the processing vessel 102 and the mounting table 110. In the example of FIG. 3, 16 electromagnets 191 are arranged in a ring shape so as to correspond one-to-one with the 16 electromagnets 181. The third electromagnet group 190 has a different magnetic pole orientation from the second electromagnet group 180. That is, the magnetic poles of the electromagnets 191 and the magnetic poles of the electromagnets 181 are set so that the magnetic poles of all the electromagnets 191 and the magnetic poles of all the electromagnets 181 are opposite to each other. In the example of FIG. 3, the magnetic poles of the 16 electromagnets 191 and the magnetic poles of the 16 electromagnets 181 are opposite to each other. 3, the third electromagnet group 190 and the second electromagnet group 180 form a magnetic field that extends radially from the side surface of the mounting table 110 around the mounting surface 110a of the mounting table 110. The magnetic field that extends radially and is formed by the third electromagnet group 190 and the second electromagnet group 180 is hereinafter referred to as a "second magnetic field."

[0038] In the plasma processing apparatus 100, a first magnetic field is formed by the first electromagnet group 170 and a second magnetic field is formed by the second electromagnet group 180 and the third electromagnet group 190 in a state where plasma is generated in the processing vessel 102 by the induced electric field from the antenna element 142. The first magnetic field is a horizontal magnetic field that crosses the plasma generated in the processing vessel 102, and the second magnetic field is a horizontal magnetic field formed around the mounting surface 110a of the mounting table 110. When the first magnetic field and the second magnetic field are formed in the processing vessel 102, electrons in the plasma are wound around the magnetic field lines of the first magnetic field and the second magnetic field, which are horizontal magnetic fields, and move back and forth along the magnetic flux lines. In addition, the Larmor radius becomes smaller as the magnetic flux density increases, so that the electron density at the height of the magnet where the magnetic flux density is high increases, and the electron density in the periphery (above and below the center of the magnet) decreases. In addition, since positive ions in the plasma are attracted to electrons to maintain electrical neutrality, the density of positive ions in the height direction is also highest at the height of the magnet center. The first magnetic field crosses the plasma generated in the processing vessel 102, thereby capturing ions (e.g., positive ions) in the plasma located above the mounting surface 110a of the mounting table 110. Most of the ions (e.g., positive ions) in the plasma are captured by the first magnetic field. However, another part of the ions in the plasma is not captured by the first magnetic field and falls toward the wafer W on the mounting surface 110a of the mounting table 110. The second magnetic field captures the ions that are not captured by the first magnetic field and fall around the mounting surface 110a of the mounting table 110. As a result, the ion density is maintained near the center of the wafer W on the mounting surface 110a of the mounting table 110, while only the ion density near the edge of the wafer W increases. On the other hand, the radicals in the plasma, which are electrically neutral, fall toward the wafer W without being subjected to the forces from the first magnetic field and the second magnetic field. As a result, the ratio of ions to radicals at the center and edge of the wafer W can be independently controlled.

[0039] The third electromagnet group 190 may be configured to move in the vertical direction along the outer periphery of the processing vessel 102. The movement of the third electromagnet group 190 is realized by a moving mechanism (not shown). FIG. 4 is a diagram for explaining the movement of the third electromagnet group 190 according to the present embodiment. FIG. 4(A) shows a state in which the third electromagnet group 190 is at the same height position as the second electromagnet group 180. In a state in which plasma is generated in the processing vessel 102 by the induced electric field from the antenna element 142, a second magnetic field M is formed around the mounting surface 110a of the mounting table 110 by the third electromagnet group 190 and the second electromagnet group 180. The third electromagnet group 190 moves upward from the same height position as the second electromagnet group 180 along the outer periphery of the processing vessel 102. FIG. 4(B) shows a state after the third electromagnet group 190 has moved. The third electromagnet group 190 moves along the outer periphery of the processing vessel 102 to a position higher than the same height position as the second electromagnet group 180, so that the second magnetic field M is inclined in a direction approaching the outer edge of the mounting surface 110a all around the periphery of the mounting surface 110a of the mounting table 110. This confines plasma on the mounting surface 110a of the mounting table 110. This promotes an increase in ion density near the edge of the wafer W. As a result, the controllability of the ratio of ions to radicals at the edge of the wafer W can be improved.

[0040] (effect) As described above, the plasma processing apparatus 100 according to this embodiment includes the processing vessel 102, the dielectric 104, the high frequency antenna 140, the first electromagnet group 170, the second electromagnet group 180, and the third electromagnet group 190. The processing vessel 102 includes a mounting table 110 having a mounting surface 110a on which a wafer W is mounted, and plasma processing is performed on the wafer W. The dielectric 104 has a facing surface 104a facing the mounting surface 110a of the mounting table 110. The high frequency antenna 140 is provided on a surface 104b of the dielectric 104 opposite to the facing surface 104a, and generates plasma by introducing an induced electric field into the processing vessel 102 via the dielectric 104. The first electromagnet group 170 is provided at a position on the outer periphery of the processing vessel 102 higher than the mounting surface 110a of the mounting table 110, and forms a first magnetic field across the processing vessel 102 above the mounting surface 110a of the mounting table 110. The second electromagnet group 180 is provided inside the mounting table 110 along the outer periphery of the mounting table 110. The third electromagnet group 190 is provided at a position on the outer periphery of the processing vessel 102 corresponding to the second electromagnet group 180, and forms a second magnetic field around the mounting surface 110a of the mounting table 110 in cooperation with the second electromagnet group 180. This allows the plasma processing apparatus 100 to independently control the ratio of ions to radicals at the center and edge of the object to be processed (for example, a wafer W).

[0041] The third electromagnet group 190 may have magnetic poles oriented in a different direction from those of the second electromagnet group 180. This allows the plasma processing apparatus 100 to form a second magnetic field capable of capturing ions around the mounting surface 110a of the mounting table 110 based on the magnetic poles of the electromagnets of the third electromagnet group 190 and the magnetic poles of the electromagnets of the second electromagnet group 180.

[0042] The third electromagnet group 190 may be provided at the same height as the second electromagnet group 180 on the outer periphery of the processing vessel 102 or at a higher height than the second electromagnet group 180. This allows the plasma processing apparatus 100 to efficiently form a second magnetic field capable of capturing ions around the mounting surface 110a of the mounting table 110.

[0043] The third electromagnet group 190 may be provided to be movable in the vertical direction along the outer periphery of the processing vessel 102. This allows the plasma processing apparatus 100 to improve the controllability of the ratio of ions to radicals at the edge of the object to be processed (for example, the wafer W).

[0044] (Modification) In the above embodiment, the first electromagnet group 170 forms the first magnetic field in the entire area above the mounting surface 110a of the mounting table 110, but the disclosed technology is not limited to this. For example, the first electromagnet group 170 may form an area where the first magnetic field is formed and an area where the first magnetic field is not formed above the mounting surface 110a of the mounting table 110 by selectively turning on / off each electromagnet 171 of the first electromagnet group 170. The on / off of each electromagnet 171 of the first electromagnet group 170 is executed according to the control of the control unit 200. FIG. 5 is a diagram showing an example of the first magnetic field formed for each area. For example, the first electromagnet group 170 forms the first magnetic field only in an area near the outer edge of the mounting surface 110a by turning off four electromagnets 171 arranged on either side of the mounting surface 110a of the mounting table 110 and turning on the other electromagnets 171. Then, the first magnetic field captures ions in the plasma corresponding to the area near the outer edge of the mounting surface 110a. As a result, the amount of ions is locally suppressed near the edge of the wafer W on the mounting surface 110a of the mounting table 110. FIG. 6 is a diagram showing another example of the first magnetic field formed for each area. For example, the first electromagnet group 170 forms a first magnetic field only in the area near the center of the mounting surface 110a by turning on four electromagnets 171 arranged on either side of the mounting surface 110a of the mounting table 110 and turning off the other electromagnets 171. Then, the first magnetic field captures ions in the plasma corresponding to the area near the center of the mounting surface 110a. As a result, the amount of ions is locally suppressed near the center of the wafer W on the mounting surface 110a of the mounting table 110.

[0045] In the above embodiment, the second electromagnet group 180 and the third electromagnet group 190 form the second magnetic field in the entire area around the mounting surface 110a of the mounting table 110, but the disclosed technology is not limited to this. For example, the second electromagnet group 180 and the third electromagnet group 190 may form an area where the second magnetic field is formed and an area where the second magnetic field is not formed around the mounting surface 110a of the mounting table 110 by selectively turning on / off each of the electromagnets 181 and 191. The ON / OFF of each of the electromagnets 181 and 191 of the second electromagnet group 180 and the third electromagnet group 190 is performed according to the control of the control unit 200. FIG. 7 is a diagram showing an example of the second magnetic field formed for each area. For example, the second electromagnet group 180 and the third electromagnet group 190 form a second magnetic field in an area arranged on either side of the mounting surface 110a of the mounting table 110 by turning off 16 electromagnets 181, 191 and turning on the other electromagnets. Then, the second magnetic field captures ions in the plasma corresponding to the area arranged on either side of the mounting surface 110a. As a result, the amount of ions is locally suppressed near the edge of the wafer W on the mounting surface 110a of the mounting table 110.

[0046] In the above-described embodiment, the first electromagnet group 170, the second electromagnet group 180, and the third electromagnet group 190 may rotate the magnetic field (i.e., the first magnetic field or the second magnetic field) formed about the central axis of the processing vessel 102. This makes it possible to uniformize the distribution of ion density in the circumferential direction of the processing vessel 102. The rotation of the magnetic field is realized by using a rotation mechanism (not shown). The magnetic field may be rotated by changing the magnetic poles of the electromagnets of the first electromagnet group 170, the second electromagnet group 180, and the third electromagnet group 190.

[0047] Although the embodiments have been described above, the embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. Indeed, the above-described embodiments may be embodied in various forms. Furthermore, the above-described embodiments may be omitted, substituted, or modified in various forms without departing from the scope and spirit of the claims. [Explanation of symbols]

[0048] 100 Plasma treatment device 102 Processing vessel 104 Dielectric 104a Opposite surface 104b side 110 Placement table 110a Placement surface 140 High Frequency Antenna 142 Antenna Element 170 First Electromagnet Group 171, 181, 191 Electromagnets 180 Second Electromagnet Group 190 Third Electromagnet Group 200 Control section 210 Operation section 220 Storage section W wafer

Claims

1. a processing vessel in which a mounting table having a mounting surface on which a processing object is placed is provided and in which a plasma processing is performed on the processing object; a dielectric body having a facing surface facing the mounting surface of the mounting table; an antenna provided on a surface opposite to the facing surface of the dielectric, the antenna generating plasma by introducing an induction electric field into the processing vessel via the dielectric; a first electromagnet group that is provided at a position higher than a mounting surface of the mounting table on an outer periphery of the processing vessel and that forms a first magnetic field across the processing vessel above the mounting surface of the mounting table; a second electromagnet group provided inside the mounting table along an outer periphery of the mounting table; a third electromagnet group provided at a position corresponding to the second electromagnet group on the outer periphery of the processing vessel, and cooperating with the second electromagnet group to form a second magnetic field around the mounting surface of the mounting table; having the first electromagnet group forms a first area in which the first magnetic field is formed and a second area in which the first magnetic field is not formed above a mounting surface of the mounting table by selectively turning on / off each electromagnet of the first electromagnet group; the second electromagnet group and the third electromagnet group selectively turn on / off each electromagnet of the second electromagnet group and the third electromagnet group to form a third area in which the second magnetic field is formed around the mounting surface of the mounting table and a fourth area in which the second magnetic field is not formed; The third area is positioned so as to overlap the second area when viewed from above the placement surface. Plasma processing equipment.

2. The plasma processing apparatus according to claim 1 , wherein the third group of electromagnets has a magnetic pole orientation different from that of the second group of electromagnets.

3. 3 . The plasma processing apparatus of claim 2 , wherein the third electromagnet group is provided at a height position on the outer periphery of the processing vessel that is the same as that of the second electromagnet group or at a higher height position than that of the second electromagnet group.

4. 4. The plasma processing apparatus according to claim 1, wherein the third electromagnet group is provided so as to be vertically movable along an outer periphery of the processing vessel.

5. 5. The plasma processing apparatus of claim 1, wherein the first group of electromagnets, the second group of electromagnets, and the third group of electromagnets rotate the magnetic fields they form about a central axis of the processing vessel.

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