Substrate Processing Equipment

Abstract

The present invention provides an apparatus for processing a substrate, the apparatus for processing a substrate comprising a chamber having a processing space, a supporting unit for supporting a substrate in the processing space, a gas supply unit for supplying a process gas to the processing space, and a plasma generating unit for generating plasma from the process gas, the plasma generating unit including an inner coil section, an outer coil section provided to surround the inner coil section when viewed from above, an upper power source for applying power to the inner coil section and the outer coil section, and a ground plate disposed above the inner coil section and the outer coil section to ground the inner coil section and the outer coil section.

Description

[Technical Field]

[0001] The present invention relates to an apparatus for processing a substrate, and more particularly to a substrate processing apparatus for processing a substrate by utilizing plasma. [Background technology]

[0002] Plasma is an ionized gas state consisting of ions, radicals, and electrons, and is generated by very high temperatures, strong electric fields, or RF electromagnetic fields. Semiconductor device manufacturing processes include ashing and etching processes that use plasma to remove film materials on substrates. The ashing and etching processes are carried out when ion and radical particles contained in the plasma collide with or react with film materials on the substrate.

[0003] The plasma generating units that generate the plasma described above can be broadly divided into capacitively coupled plasma (CCP) types and inductively coupled plasma (ICP) types. The ICP type includes an inner coil module 10 and an outer coil module 20, as shown in FIG. 1. The inner coil module 10 includes a first inner coil 11 and a second inner coil 12. The outer coil module 20 includes a first outer coil 21, a second outer coil 22, and a third outer coil 23. One end of the first inner coil 11 is formed with a ground port 11a to which a ground line is connected and a power port 11b to which a power supply line is connected. Similar to the first inner coil 11, the second inner coil 12 is also formed with a ground port 12a and a power port 12b. The first outer coil 21 and the second outer coil 22 are arranged to surround the inner coil module 10 when viewed from above. The first outer coil 21 has a ground port 11a to which a ground line is connected and a power port 21b to which a power supply line is connected. Similar to the first outer coil 21, the second outer coil 22 also has a ground port 22a and a power port 22b. Similar to the first outer coil 21, the third outer coil 23 also has a ground port 23a and a power port 23b. That is, the inner coil module 10 is composed of two turns. The outer coil module 20 is also composed of two turns. The inner coil module 10 and the outer coil module 20 receive power from a high-frequency power source to generate plasma in a space within a chamber where a substrate such as a wafer is processed.

[0004] Figure 2 is a graph showing the plasma density generated by the outer coils of Figure 1 as a function of distance from the center of the chamber, and Figure 3 is a graph showing the plasma density generated by the inner coils of Figure 2 as a function of distance from the center of the chamber. Figures 2 and 3 show the change in plasma density (PD) as a function of distance from the center of the chamber (e.g., the center of a substrate placed in the chamber). When viewed from above, Figures 2 and 3 show the plasma density (PD) in a first direction, the plasma density (PD) in a second direction perpendicular to the first direction, and the plasma density (PD) in a third and fourth direction angled 45 degrees from the first and second directions.

[0005] As shown in Figures 2 and 3, the plasma density (PD) generated by the inner coils 11 and 12 and the outer coils 21 and 22 is non-uniform from the center of the chamber to the left and right. This is because, when imaginary lines are drawn from the center of the chamber, one of the imaginary lines, a first imaginary line (L1), passes through only the first outer coil 21 of the first through third outer coils 21 through 23, while the other imaginary line, a second imaginary line (L2), passes through both the first outer coil 21 and the third outer coil 23. In other words, the first and second outer coils 21 and 22 are structurally asymmetric with respect to the space within the chamber. Similarly, the first and second inner coils 11 and 12 are structurally asymmetric with respect to the space within the chamber. In other words, the structural asymmetry of the coils causes the density of the plasma generated within the chamber to be non-uniform. If the density of the plasma generated in the space within the chamber is non-uniform, the processing uniformity for the substrate will also be poor. DISCLOSURE OF THE INVENTION [Problem to be solved by the invention]

[0006] [Technical issues] An object of the present invention is to provide a plasma generating unit and a substrate processing apparatus that can process substrates efficiently.

[0007] Another object of the present invention is to provide a plasma generating unit and a substrate processing apparatus that can improve processing uniformity for a substrate.

[0008] Another object of the present invention is to provide a plasma generating unit and a substrate processing apparatus that can further ensure a plasma density control range.

[0009] The problems to be solved by the present invention are not limited to the above-mentioned problems, and problems not mentioned will be clearly understood by a person having ordinary skill in the art to which the present invention pertains from this specification and the accompanying drawings. [Means for solving the problem]

[0010] [Technical solution] According to one embodiment, the substrate processing apparatus includes a chamber having a processing space, a support unit for supporting a substrate in the processing space, a gas supply unit for supplying a process gas to the processing space, and a plasma generating unit for generating plasma from the process gas, the plasma generating unit including an inner coil unit having a plurality of inner coils, an outer coil unit having a plurality of outer coils surrounding the inner coil unit when viewed from above, and an upper power supply for applying power to the inner coil unit and the outer coil unit, the inner coil and the outer coil being respectively provided concentrically with each other. The internal coils and the external coils each have a first portion to an nth portion and a first connecting portion to an n-1th connecting portion, where n is a natural number greater than or equal to 2, the first portion to the nth portion are each provided in an arc shape having a different radius based on the concentricity, the k+1th portion has a larger radius than the kth portion, the kth connecting portion connects the kth portion to the k+1th portion, where k is a natural number greater than or equal to 1 and less than n-1, one of the first portion and the nth portion has a power terminal to which a power line that receives power from the power source is connected, and the other of the first portion and the nth portion has a ground terminal to which a ground line is connected, and the power terminal and the ground terminal of the internal coils and the external coils are positioned on a straight line passing through the concentricity.

[0011] According to one embodiment, the ground terminal, the power terminal, and the concentricity may be sequentially arranged on the straight line.

[0012] According to one embodiment, a power terminal connected to one of the internal coils, a power terminal connected to one of the external coils, and the concentricity may be arranged on the same line.

[0013] According to one embodiment, in any one of the internal coils or any one of the external coils, the straight line passing through the concentricity may pass through only one of the first portion and the nth portion.

[0014] According to an embodiment, each of the first to (n-1)th connection parts may be provided to be inclined with respect to a straight line passing through the concentric center.

[0015] According to one embodiment, n may be three.

[0016] According to an embodiment, three of the internal coils and three of the external coils may be provided.

[0017] According to one embodiment, the inner coils and the outer coils may all be arranged on the same plane.

[0018] According to one embodiment, each of the inner coils and the outer coils has a central angle of 360 degrees, and each of the first to nth portions has an equal central angle.

[0019] According to an embodiment, the antenna may further include a ground plate disposed on the coil portion, and the ground terminal may be connected to the ground plate.

[0020] According to one embodiment, the chamber includes a lower body, a cover that is combined with the lower body to form the processing space, an upper body that is combined with the cover to form an internal space in which the internal coil portion and the external coil portion are disposed, and a fan unit that supplies airflow to the internal space, and the ground plate is disposed in the internal space, and openings may be formed in the ground plate to allow the airflow to circulate in the internal space.

[0021] According to one embodiment, the fan unit includes a first fan and a second fan that supplies the airflow to the internal space at a position different from the first fan, and the opening may be formed in the ground plate at a position overlapping the first fan and / or the second fan when viewed from above.

[0022] According to one embodiment, the inner coil and the outer coil may be made of a material including at least one of copper, aluminum, tungsten, silver, gold, platinum, and iron.

[0023] According to one embodiment, the surfaces of the inner coil and the outer coil may be coated with a material including at least one of silver, gold, and platinum.

[0024] According to one embodiment, the ground plate may be made of a material including at least one of aluminum, copper, and iron.

[0025] According to another embodiment, a substrate processing apparatus includes a chamber having a processing space, a supporting unit for supporting a substrate in the processing space, a gas supply unit for supplying a process gas to the processing space, and a plasma generating unit for generating plasma from the process gas, the plasma generating unit having a coil unit including a plurality of coils and an upper power supply for applying power to the coil unit, each of the coils having a first portion to an nth portion and a first connection portion to an n-1th connection portion, n being a natural number of 2 or more, the first portion to the nth portion being arc-shaped and concentric with each other. The k+1 portion of the first to n portions has a larger radius than the k portion, the k connecting portion connects the k portion and the k+1 portion, where k is a natural number greater than or equal to 1 and less than or equal to n-1, one of the first and n portions has a power terminal to which a power line that receives power from the power source is connected, and the other of the first and n portions has a ground terminal to which a ground line is connected, and the power terminal and the ground terminal of each of the coils are located on a straight line passing through the concentric center.

[0026] According to an embodiment, the ground terminal, the power terminal, and the concentric core connected to any one of the coils may be sequentially arranged on the straight line.

[0027] According to one embodiment, the straight line passing through the concentricity may pass through only one of the first portion to the (n+1)th portion in any one of the coils.

[0028] Each of the first to (n-1)th connection portions may be provided to be inclined with respect to a straight line passing through the concentric center.

[0029] According to one embodiment, the coils may all be arranged on the same plane.

[0030] According to another embodiment, an apparatus for processing a substrate includes a chamber having a processing space, a supporting unit for supporting a substrate in the processing space, a gas supply unit for supplying a process gas to the processing space, and a plasma generating unit for generating plasma from the process gas, the plasma generating unit including an inner coil section including a plurality of inner coils, an outer coil section including a plurality of outer coils provided to surround the inner coil section when viewed from above, and an upper power supply for applying power to the inner coil section and the outer coil section, the inner coils and the outer coils being provided concentrically with each other, and the inner coils and the outer coils being provided concentrically with each other, and a first portion provided in an arc shape having a first radius based on the concentricity, the first portion being concentric with the concentricity, and the second portion being concentric with the concentricity. a second portion provided in an arc shape having a second radius based on the concentricity; a third portion provided in an arc shape having a third radius based on the concentricity; a first connecting portion connecting the other end of the first portion to one end of the second portion; and a second connecting portion connecting the other end of the second portion to one end of the third portion, the first connecting portion and the second connecting portion being provided so as to be inclined with respect to a line passing through the concentricity; one of the first portion and the three portions having a power terminal to which a power line that receives power from the power source is connected, and the other of the first portion and the three portions having a ground terminal to which a ground line is connected; and the power terminal and the ground terminal of the internal coil and the external coil, respectively, may be positioned on a line passing through the concentricity.

[0031] According to one embodiment, the ground terminal, the power terminal, and the concentric core are sequentially arranged on the straight line, one power terminal of the internal coils, one power terminal of the external coils, and the concentric core are arranged on the straight line, and the straight line passing through the concentric core passes through only one of the first to third parts, and the internal coils and the external coils can all be arranged on the same plane.

[0032] According to an embodiment, the antenna may further include a ground plate disposed on the coil portion, and the ground terminal may be connected to the ground plate.

[0033] According to one embodiment, the chamber includes a lower body, a cover combined with the lower body to form the processing space, an upper body combined with the cover to form an internal space in which the internal coil portion and the external coil portion are disposed, and a fan unit that supplies airflow to the internal space, the ground plate is disposed in the internal space, and an opening is formed in the ground plate to allow the airflow to circulate in the internal space, the fan unit includes a first fan and a second fan at a position different from the first fan to supply the airflow to the internal space, and the opening may be formed in the ground plate at a position overlapping the first fan and / or the second fan when viewed from above. [Effects of the Invention]

[0034] According to one embodiment of the present invention, substrates can be processed efficiently.

[0035] According to one embodiment of the present invention, processing uniformity across a substrate can be improved.

[0036] Furthermore, according to an embodiment of the present invention, a wider plasma density control range can be ensured.

[0037] The effects of the present invention are not limited to the effects described above, and effects not mentioned will be clearly understood by those skilled in the art to which the present invention pertains from this specification and the accompanying drawings. [Brief explanation of the drawings]

[0038] [Figure 1] FIG. 1 is a top view of a coil included in a general plasma generating unit. [Figure 2] FIG. 2 is a graph showing the plasma density generated by the outer coils of FIG. 1 as a function of distance from the center of the chamber. [Figure 3]FIG. 3 is a graph showing the plasma density generated by the inner coil of FIG. 2 as a function of the distance from the center of the space within the chamber. [Figure 4] FIG. 4 is a schematic diagram of a substrate processing apparatus according to an embodiment of the present invention. [Figure 5] FIG. 5 is a top view of the inner coil section and the outer coil section of FIG. [Figure 6] FIG. 6 is a graph showing the plasma density generated by the external coil portion of FIG. 4 as a function of the distance from the center of the processing space. [Figure 7] FIG. 7 is a graph showing the plasma density generated by the internal coil portion of FIG. 4 as a function of the distance from the center of the processing space. [Figure 8] Figure 8 shows the impedance measurement results of the internal coil when the ground plate of Figure 4 is not installed. [Figure 9] Figure 9 shows the results of measuring the impedance of the external coil when the ground plate shown in Figure 4 is not installed. [Figure 10] Figure 10 shows the results of measuring the impedance of the internal coil when the ground plate shown in Figure 4 is installed. [Figure 11] Figure 11 shows the results of measuring the impedance of the external coil when the ground plate shown in Figure 4 is installed. [Figure 12] FIG. 12 is a graph showing current measurements for the inner and outer coils of FIG. [Figure 13] Figure 13 is a graph showing the current measurement results for the internal coil and external coil when the ground plate of Figure 4 is not installed. [Figure 14] Figure 14 is a graph showing the current measurement results for the internal and external coils when the ground plate shown in Figure 4 is installed. DETAILED DESCRIPTION OF THE INVENTION

[0039] [Best Mode for Carrying Out the Invention] Hereinafter, with reference to the accompanying drawings, embodiments of the present invention will be described in detail so that those skilled in the art can easily implement the present invention. However, the present invention may be embodied in various different forms and is not limited to the embodiments described herein. Furthermore, in describing preferred embodiments of the present invention in detail, detailed description of related well-known functions or configurations will be omitted if it is determined that such detailed description may unnecessarily obscure the gist of the present invention. Furthermore, the same reference numerals will be used throughout the drawings to refer to parts having similar functions and functions.

[0040] "Including" a certain element does not mean excluding other elements, but may further include other elements, unless specifically stated to the contrary. Specifically, terms such as "comprise" or "have" are intended to specify the presence of features, numbers, steps, operations, elements, parts, or combinations thereof described in the specification, and should be understood as not precluding the presence or possibility of addition of one or more other features, numbers, steps, operations, elements, parts, or combinations thereof.

[0041] The singular expression includes the plural expression unless the context clearly dictates otherwise. Also, in the drawings, the shapes and sizes of elements may be exaggerated for clearer explanation.

[0042] Terms such as "first" and "second" may be used to describe various components, but the components should not be limited by these terms. These terms may be used to distinguish one component from another. For example, a first component may be referred to as a second component, and similarly, a second component may be referred to as a first component, without departing from the scope of the present invention.

[0043] Hereinafter, an embodiment of the present invention will be described in detail with reference to FIGS.

[0044] 4 is a schematic diagram of a substrate processing apparatus according to an embodiment of the present invention, which may include a chamber 100, a supporting unit 200, a gas supply unit 300, a gas exhaust unit 400, a fan unit 500, a plasma generation unit 600, and a controller (not shown).

[0045] The chamber 100 may have a processing space 102 and an inner space 104. For example, the chamber 100 may include a lower body 110, a cover 120, and an upper body 130. The lower body 110 may have a tub shape with an open top. The cover 120 may be disposed on top of the lower body 110. The cover 120 may be combined with the lower body 110 to form the processing space 102. The upper body 130 may be disposed on top of the cover 120. The upper body 130 may have a tub shape with an open bottom. The upper body 130 may be combined with the cover 120 to form the inner space 104. The inner space 104 may be disposed above the processing space 102. The processing space 102 may be used as a space where a substrate (W) is supported by a support unit 200 (described below) and where the substrate (W) is processed. The inner space 104 may be used as a space where an inner coil unit 610, an outer coil unit 630, and a ground plate 670 (described below) are disposed. The chamber 100 may be grounded. A gas supply pipe 122 connected to a supply line 320 (described later) may be provided at the center of the cover 120.

[0046] The support unit 200 can support a substrate W from the processing space 102. The support unit 200 can chuck the substrate W. The support unit 200 can include a chuck 210, an insulating ring 220, a focus ring 230, a chuck cover 240, and an interface cover 250.

[0047] The chuck 210 may have a mounting surface that supports the lower surface of the substrate (W). The chuck 210 may be an ESC. The substrate (W) placed on the chuck 210 may be a wafer. Power may be applied to the chuck 210. For example, high frequency power applied by a lower power source 212 may be transmitted to the chuck 210. In addition, a first matcher 214 may be installed between the lower power source 212 and the chuck 210 to perform matching for the high frequency power applied by the lower power source 212.

[0048] The insulating ring 220 may be provided to surround the chuck 210 when viewed from above. A focus ring 230 may be placed on the upper surface of the insulating ring 220. The upper surface of the focus ring 230 may be stepped so that the inner height is lower than the outer height. The lower surface of the edge region of the substrate (W) placed on the chuck 210 may be placed inside the focus ring 230. That is, the central region of the substrate (W) may be placed on the mounting surface of the chuck 210, and the edge region of the substrate (W) may be placed on the inner upper surface of the focus ring 230.

[0049] The chuck cover 240 may be disposed below the chuck 210. The chuck cover 240 may generally have a barrel shape with an open top. The chuck cover 240 may be disposed below the chuck 210 to form a lower space. Interface lines required to drive the support unit 200 may be provided in the lower space. These interface lines may be connected to devices outside the chamber 100 through an interface cover 250 having a space communicating with the lower space of the chuck cover 240.

[0050] The gas supply unit 300 may supply a process gas to the processing space 102. The process gas supplied to the processing space 102 by the gas supply unit 300 may include at least one of CF4, N2, Ar, H2, O2, and O*. However, the process gas supplied to the processing space 102 by the gas supply unit 300 is not limited thereto, and may be variously modified from known process gases.

[0051] The gas supply unit 300 may include a gas supply source 310, a supply line 320, and a supply valve 330. The gas supply source 310 may deliver or store the process gas to the supply line 320. The supply line 320 may receive the process gas from the gas supply source 310. One end of the supply line 320 may be connected to the gas supply pipe 122, and the other end of the supply line 320 may be connected to the gas supply source 310. A supply valve 330 may be installed on the supply line 320. The supply valve 330 may be an on-off valve. However, the present invention is not limited thereto, and the supply valve 330 may also be a flow control valve.

[0052] The gas exhaust unit 400 can exhaust process gases supplied to the processing space 102 and process by-products that may be generated during the process of processing a substrate (W) from the processing space 102. The gas exhaust unit 400 can include a pressure reducing member 410, a pressure reducing line 420, a pressure reducing valve 430, and a vent plate 440.

[0053] The pressure reducing member 410 may provide a reduced pressure to the processing space 102. The pressure reducing member 410 may be a pump. However, the pressure reducing member 410 is not limited to this and may be variously modified from a known device capable of providing a reduced pressure to the processing space 102. The reduced pressure provided by the pressure reducing member 410 may be transmitted to the processing space 102 through a pressure reducing line 420 fluidly communicating with the processing space 102. A pressure reducing valve 430 may be installed in the pressure reducing line 420. The pressure reducing valve 430 may be an on-off valve. However, the pressure reducing valve 430 is not limited to this and may be a flow control valve. The vent plate 440 may have a ring shape when viewed from above. The vent plate 440 may be provided to surround the support unit 200 when viewed from above. A plurality of vent holes may be formed in the vent plate 440.

[0054] The fan unit 500 can supply airflow to the interior space 104. The fan unit 500 can supply temperature- and humidity-controlled airflow to the interior space 104. The fan unit 500 can act as a cooler to prevent the temperature of the interior space 104 from becoming excessively high. The fan unit 500 can include a first fan 510 and a second fan 520. The first fan 510 and the second fan 520 can supply airflow to the interior space 104 at different positions. The first fan 510 and the second fan 520 can supply airflow to the interior space 104 in a downward direction.

[0055] The plasma generating unit 600 can generate plasma from the process gas supplied to the processing space 102. The plasma generating unit 600 can include an inner coil unit 610, an outer coil unit 630, a power applying unit 650, a ground plate 670, and a power line (EL).

[0056] The inner coil unit 610 and the outer coil unit 630 may be disposed in the inner space 104. The inner coil unit 610 and the outer coil unit 630 may receive high frequency power from a power application unit 650 (described later) to generate plasma from the process gas supplied to the processing space 102.

[0057] The internal coil unit 610 may include a plurality of internal coils, and the external coil unit 630 may include a plurality of external coils. The external coil unit 630 may surround the internal coil unit 610 when viewed from above. The internal coils and external coils are concentric with each other. Each of the internal coils and external coils has first through nth sections and first through n-1th connection sections, where n is a natural number greater than or equal to 2. The first through nth sections are arc-shaped with different radii based on the concentricity. The k+1th section has a larger radius than the kth section. The kth connection section connects the kth section to the k+1th section, where k is a natural number greater than or equal to 1 and less than or equal to n-1. One of the first and nth sections has a power terminal 611a to which a power line (EL) that receives power from a power source is connected, and the other of the first and nth sections has a ground terminal 611b to which a ground line (GL) is connected. The power terminal 611a and the ground terminal 611b of each of the inner and outer coils are positioned on a straight line passing through the same center.

[0058] In the following, an example will be described in which three internal coils and three external coils are provided, and each internal coil and external coil has first to third portions and first and second connecting portions.

[0059] FIG. 5 is a top view of the internal coil unit and the external coil unit of FIG. 4. Referring to FIG. 5, the internal coil unit 610 may be disposed at a position corresponding to the central region of the processing space 102 when viewed from above. The external coil unit 630 may be disposed at a position corresponding to the edge region of the processing space 102 when viewed from above. The external coil unit 630 may be provided to surround the internal coil unit 610 when viewed from above. The internal coil unit 610 may include a first internal coil 611, a second internal coil 612, and a third internal coil 613. The external coil unit 630 may include a first external coil 631, a second external coil 632, and a third external coil 633. The internal coil unit 610 may also include a ground line (GL) described below. The external coil unit 630 may also include a ground line (GL) described below.

[0060] The first internal coil 611, the second internal coil 612, and the third internal coil 613 have the same or similar shapes, so the first internal coil 611 will be described in detail below. The first internal coil 611 may have a latch shape. One end of the first internal coil 611 may have a power terminal 611a to which a power line (EL) (described below) is connected, and the other end of the first internal coil 611 may have a ground terminal 611b to which a ground line (GL) (described below) is connected. When viewed from above, the power terminal 611a may be located closer to the center of the processing space 102 than the ground terminal 611b. Furthermore, the power terminal 611a and the ground terminal 611b may be arranged on an imaginary straight line drawn from the center of the substrate (W) supported by the support unit 200 (i.e., from the center of the chamber 102) in the radial direction of the substrate (W) (i.e., toward the edge of the chamber 102). That is, the power terminal 611a and the ground terminal 611b may be arranged on a straight line. Similarly, a power terminal 612a is formed at one end of the second internal coil 612, and a ground terminal 612b is formed at the other end, where the power terminal 612a and the ground terminal 612b may be arranged on an imaginary line (LB) drawn from the center of the chamber 102 toward the edge of the chamber 102. Similarly, a power terminal 613a is formed at one end of the third internal coil 613, and a ground terminal 613b is formed at the other end, where the power terminal 613a and the ground terminal 613b may be arranged on an imaginary line drawn from the center of the chamber 102 toward the edge of the chamber 102. That is, the second internal coil 612 and the third internal coil 613 have a shape similar to the first internal coil 611, and the internal coil portion 610 may be configured with three turns overall when viewed from above. However, this is not limited to this, and the internal coil portion 610 may be configured with more than three turns overall.

[0061] When viewed from above, the number of overlaps of imaginary lines LA drawn from the center of the substrate W supported by the support unit 200 in the radial direction of the substrate W supported by the support unit 200 with the internal coils 611, 612, and 613 may be three, except for the fulcrums where the power terminals 611a, 612a, and 613a and the ground terminals 611b, 612b, and 613b are formed. The distance between the first internal coil 611 and the second internal coil 612 may be 10 mm or more. The distance between the second internal coil 612 and the third internal coil 613 may be 10 mm or more. The diameters of the first internal coil 611, the second internal coil 612, and the third internal coil 613 viewed from their cross sections may be 5 to 50 mm.

[0062] The first external coil 631, the second external coil 632, and the third external coil 633 may have the same or similar shapes, so the first external coil 631 will be described in detail below. The first external coil 631 may have a latch shape. One end of the first external coil 631 may have a power terminal 631a to which a power line (EL) (described below) is connected, and the other end of the first external coil 631 may have a ground terminal 631b to which a ground line (GL) (described below) is connected. When viewed from above, the power terminal 631a may be provided in an area adjacent to the center of the processing space 102 relative to the ground terminal 631b. Furthermore, the power terminal 631a and the ground terminal 631b may be arranged on an imaginary straight line drawn from the center of the substrate (W) supported by the support unit 200 (i.e., from the center of the chamber 102) in the radial direction of the substrate (W) (i.e., toward the edge of the chamber 102). That is, the power terminal 631a and the ground terminal 631b may be arranged on a straight line.

[0063] Similarly, a power terminal 632a is formed at one end of the second external coil 632, and a terminal 632b is formed at the other end, with the power terminal 631a and ground terminal 632b being disposed on an imaginary line (LB) drawn from the center of the chamber 102 toward the edge of the chamber 102. Similarly, a power terminal 633a is formed at one end of the third external coil 633, and a ground terminal 633b is formed at the other end, with the power terminal 633a and ground terminal 633b being disposed on an imaginary line drawn from the center of the chamber 102 toward the edge of the chamber 102. That is, the second external coil 632 and the third external coil 633 have a shape similar to the first external coil 631, and the external coil portion 630 may be configured with three turns overall when viewed from above. However, this is not limited thereto, and the external coil portion 630 may be configured with more than three turns overall.

[0064] When viewed from above, the number of overlaps of imaginary lines LA drawn from the center of the substrate W supported by the support unit 200 in the radial direction of the substrate W supported by the support unit 200 with the external coils 631, 632, and 633 may be equal to three, except for the fulcrums where the power terminals 631a, 632a, and 633a and the ground terminals 631b, 632b, and 633b are formed. The distance between the first external coil 631 and the second external coil 632 may be 10 mm or more. The distance between the second external coil 632 and the third external coil 633 may be 10 mm or more. The diameters of the first external coil 631, the second external coil 632, and the third external coil 633 viewed from their cross sections may be 5 to 50 mm.

[0065] In addition, when viewed from above, the power terminal 611a and the ground terminal 611b of the first internal coil 611 and the power terminal 631a and the ground terminal 631b of the first external coil 631 may be arranged on an imaginary line drawn from the center of the substrate (W) supported by the support unit 200, which is the workpiece, in a radial direction of the substrate (W) supported by the support unit 200. Similarly, the power terminal 612a and the ground terminal 612b of the second internal coil 612 and the power terminal 632a and the ground terminal 632b of the second external coil 632 may be arranged on an imaginary line (LB) drawn from the center of the substrate (W) supported by the support unit 200, which is the workpiece, in a radial direction of the substrate (W) supported by the support unit 200, when viewed from above. Similarly, when viewed from above, the power terminal 613a and the ground terminal 613b of the third internal coil 613 and the power terminal 633a and the ground terminal 633b of the third external coil 633 may be arranged on an imaginary line drawn from the center of the substrate (W) supported by the support unit 200, which is the workpiece, in the radial direction of the substrate (W) supported by the support unit 200. Furthermore, when viewed from above, the power terminals 611a, 612a, and 613a of the internal coil unit 610 may be arranged at equal intervals from each other in a circumferential direction based on the center of the processing space 102. Furthermore, when viewed from above, the power terminals 631a, 632a, and 633a of the external coil unit 630 may be arranged at equal intervals from each other in a circumferential direction based on the center of the processing space 102.

[0066] The coils of the internal coil unit 610 and the external coil unit 630 may be made of a metal material including at least one of copper, aluminum, tungsten, silver, gold, platinum, and iron. The surfaces of the coils of the internal coil unit 610 and the external coil unit 630 may be coated with a metal material including at least one of silver, gold, and platinum. This coating layer may be a metal with low resistivity and good thermal conductivity. The thickness of the coating layer may be 20 micrometers or more. The coating layer may be formed by physical vapor deposition (sputtering, evaporating), chemical vapor deposition (CVD), spraying, electroplating, or the like.

[0067] 4, the power applying unit 650 can apply high frequency power to the internal coil unit 610 and the external coil unit 630. The power applying unit 650 can include an upper power source 652 and a second matching box 654. The upper power source 652 can be a high frequency power source. The second matching box 654 can perform matching on the high frequency power applied by the upper power source 652 to the internal coil unit 610 and the external coil unit 630. In addition, one end of the power line (EL) that transmits the high frequency power generated by the upper power source 652 can be connected to the previously described power terminals 611a, 612a, 613a, 631a, 632a, and 633a.

[0068] A ground plate 670 may also be provided in the internal space 104. The ground plate 670 may be made of a metal material including at least one of aluminum, copper, and iron. The ground plate 670 may have a thickness of 3 mm or more. The ground plate 670 may be disposed at a distance of 50 mm or more from the internal coil portion 610 and the external coil portion 630. The ground plate 670 may be grounded. The ground plate 670 may ground the internal coil portion 610 and the external coil portion 630. The ground plate 670 may be disposed above the internal coil portion 610 and the external coil portion 630. An opening may also be formed in the ground plate 670 so that the airflow supplied to the internal space 104 by the fan unit 500 can circulate smoothly within the internal space 104. For example, a circular opening may be formed in a center region of the ground plate 670 when viewed from above. A plurality of arc-shaped openings may also be formed in a middle region surrounding the center region of the ground plate 670 when viewed from above. The arc-shaped opening formed in the middle region of the ground plate 670 may be formed on the ground plate 670 at a position overlapping the first fan 510 or the second fan 520 when viewed from above.

[0069] The ground line (GL) may electrically connect the ground plate 670 to the coils 611, 612, and 613 of the internal coil unit 610. The ground line (GL) may electrically connect the ground plate 670 to the coils 631, 632, and 633 of the external coil unit 630. A plurality of ground lines (GL) may be provided. A plurality of ground lines (GL) may be provided, with one end of each connected to the ground plate 670 and the other end connected to the above-mentioned ground terminals 611b, 612b, 613b, 631b, 632b, and 633b. When viewed from above, the ground lines (GL) may be arranged at equal intervals around the center of the ground plate 670 in the circumferential direction. That is, the arrangement of the ground lines (GL) is symmetrical.

[0070] A controller (not shown) can control the components of the substrate processing apparatus. For example, the controller can control the support unit 200, the gas supply unit 300, the gas exhaust unit 400, the fan unit 500, and the plasma generation unit 600. The controller can include a process controller implemented by a microprocessor (computer) that controls the substrate processing apparatus; a user interface implemented by a keyboard through which an operator inputs commands to manage the substrate processing apparatus and a display that visualizes the operating status of the substrate processing apparatus; and a memory unit that stores a control program for controlling the processes performed by the process controller and a program for causing each component to execute a process according to various data and processing conditions, i.e., a process recipe. The user interface and memory unit can be connected to the process controller. The process recipe can be stored in a storage medium within the memory unit. The storage medium can be a hard disk, a portable disk such as a CD-ROM or DVD, or a semiconductor memory such as a flash memory.

[0071] Figure 6 is a graph showing the plasma density generated by the external coil unit of Figure 4 as a function of distance from the center of the processing space, and Figure 7 is a graph showing the plasma density generated by the internal coil unit of Figure 4 as a function of distance from the center of the processing space. Figures 6 and 7 show the change in plasma density (PD) as a function of distance from the center of the processing space 102 of the chamber 100 (e.g., the center of the substrate (W) to be processed placed in the processing space 102). Figures 6 and 7 show the plasma density (PD) in a first direction, a second direction perpendicular to the first direction, and third and fourth directions angled 45 degrees from the first and second directions, when viewed from above.

[0072] 2 and 6, the uniformity of the plasma density (PD) formed in the processing space 102 by the external coil unit 630 is significantly improved. Furthermore, the uniformity of the plasma density (PD) formed in the processing space 102 by the internal coil unit 610 is significantly improved. This is because, when viewed from above, all imaginary lines (LA, LB) drawn from the center of the processing space 102 overlap with the same number of internal coils 611, 612, and 613, except for the fulcrums where the power and ground terminals are formed. Similarly, when viewed from above, all imaginary lines (LA, LB) drawn from the center of the processing space 102 overlap with the same number of external coils 631, 632, and 633, except for the fulcrums where the power and ground terminals are formed. Also, as mentioned above, the power terminals and ground terminals are arranged in a straight line when viewed from above. That is, because the plasma generation unit 600 according to an embodiment of the present invention has a highly symmetrical structure, the uniformity (left-right symmetry) of the plasma density (PD) generated in the processing space 102 is greatly improved, and this improvement in plasma density (PD) is even more pronounced when the coils are configured with three or more turns.

[0073] Figure 8 shows the results of measuring the impedance of the internal coil when the ground plate of Figure 4 is not installed, Figure 9 shows the results of measuring the impedance of the external coil when the ground plate of Figure 4 is not installed, Figure 10 shows the results of measuring the impedance of the internal coil when the ground plate of Figure 4 is installed, and Figure 11 shows the results of measuring the impedance of the external coil when the ground plate of Figure 4 is installed.

[0074] 8 and 10, and 9 and 11, the impedance of the internal coil unit 610 and the external coil unit 630 decreases when the ground plate 670 is installed. This is because the length of the ground line (GL) is shortened by the placement of the ground plate 670. In particular, the decrease in impedance is more noticeable in the case of the external coil unit 630. This decrease in impedance of the internal coil unit 610 and the external coil unit 630 allows for the use of a wider matching range within the matching system implemented by the second matching unit 654.

[0075] FIG. 12 is a graph showing current measurement results for the inner coil module 10 and the outer coil module 20 of FIG. 1, FIG. 13 is a graph showing current measurement results for the inner coil unit 610 and the outer coil unit 630 when the ground plate 670 of FIG. 4 is not installed, and FIG. 14 is a graph showing current measurement results for the inner coil unit 610 and the outer coil unit 630 when the ground plate 670 of FIG. 4 is installed. FIG. 12 shows current measurement data 10-A for the inner coil module 10 and current measurement data 20-A for the outer coil module 20. FIGS. 13 to 14 show current measurement data 610-A for the inner coil unit 610 and current measurement data 630-A for the outer coil unit 630. FIGS. 12 to 14 show results of measuring the current flowing through the inner coil unit 610 and the outer coil unit 630 by adjusting the capacity of the matching system implemented by the second matching box 654.

[0076] As can be seen from FIG. 12 in detail, the ratio of the current flowing through the inner coil module 10 to the current flowing through the outer coil module 20 can be adjusted from 3:1 to 1:4. As can be seen from FIG. 13 in detail, the ratio of the current flowing through the inner coil unit 610 to the current flowing through the outer coil unit 630 can be adjusted from 15:1 to 1:3. As can be seen from FIG. 14 in detail, the ratio of the current flowing through the inner coil unit 610 to the current flowing through the outer coil unit 630 can be adjusted from 20:1 to 1:20. That is, when the coil configuration of the inner coil unit 610 and the outer coil unit 630 is three turns or more and a ground plate 670 is installed as in one embodiment of the present invention, the ratio of the current flowing through the inner coil unit 610 to the current flowing through the outer coil unit 630 can be controlled more widely, making it easier to control the plasma density (PD).

[0077] In the above example, the plasma generating unit has been described as having both an inner coil portion and an outer coil portion, but alternatively, the plasma generating unit may have only one coil portion.

[0078] The above detailed description exemplifies the present invention. The above content illustrates and describes preferred embodiments of the present invention, and the present invention can be used in various other combinations, modifications, and environments. That is, changes or modifications are possible within the scope of the inventive concept disclosed herein, within the scope of equivalents to the disclosed content, and / or within the scope of the skill or knowledge of the art. The above-described examples illustrate the best mode for embodying the technical ideas of the present invention, and various modifications are possible as required for specific application fields and uses of the present invention. Therefore, the above detailed description of the invention is not intended to limit the present invention to the disclosed embodiments. The appended claims should be construed to include other embodiments.

Claims

1. In an apparatus for processing a substrate, a chamber having a processing space; a support unit for supporting a substrate in the processing space; a gas supply unit for supplying a process gas to the processing space; and a plasma generating unit for generating plasma from the process gas, The plasma generating unit comprises: an internal coil section including a plurality of internal coils; an outer coil section provided to surround the inner coil section when viewed from above and including a plurality of outer coils; an upper power supply for applying power to the inner coil section and the outer coil section; The inner coils and the outer coils are provided concentrically with each other, The inner coils and the outer coils each include: a first portion to an n-th portion; The first connection portion to the (n-1)th connection portion are included, and n is a natural number of 2 or more. The first to nth portions are provided in arc shapes having different radii from each other based on the concentricity, the k+1th portion has a radius larger than the kth portion, the kth connecting portion connects the kth portion and the k+1th portion, k is a natural number greater than or equal to 1 and less than or equal to n-1; One of the first portion and the nth portion has a power terminal to which a power line for receiving power from the upper power source is connected, The other of the first portion and the nth portion has a ground terminal connected to a ground line, The power terminal and the ground terminal of each of the internal coils and the external coils are located on a straight line passing through the concentric center, a ground plate disposed above the inner coil portion and the outer coil portion; The substrate processing apparatus, wherein the ground terminals of the plurality of internal coils and the plurality of external coils are respectively connected to the ground plate via the ground line.

2. The substrate processing apparatus of claim 1 , wherein the ground terminal, the power terminal, and the concentric terminal are sequentially arranged on the straight line.

3. 3. The substrate processing apparatus of claim 2, wherein a power terminal connected to one of the internal coils, a power terminal connected to one of the external coils, and the concentric coils are arranged on the same line.

4. 4. The substrate processing apparatus according to claim 1, wherein in any one of the internal coils or any one of the external coils, a straight line passing through the concentricity passes through only one of the first portion and the nth portion.

5. 4. The substrate processing apparatus of claim 1, wherein the first to (n-1)th connection portions are provided so as to be inclined with respect to a straight line passing through the concentric center.

6. 4. The substrate processing apparatus according to claim 1, wherein said n is 3.

7. 4. The substrate processing apparatus of claim 1, wherein three of the internal coils and three of the external coils are provided.

8. 4. The substrate processing apparatus according to claim 1, wherein the internal coils and the external coils are all disposed on the same plane.

9. The inner coils and the outer coils each have a central angle of 360 degrees, The substrate processing apparatus according to claim 8 , wherein the first portion to the nth portion are provided with the same central angle.

10. The chamber comprises: The lower body and a cover that is combined with the lower body to form the processing space; an upper body that is combined with the cover to form an internal space in which the inner coil portion and the outer coil portion are disposed; and a fan unit for supplying airflow to the interior space; the ground plate is disposed in the interior space; 4. The substrate processing apparatus according to claim 1, wherein the ground plate has an opening formed therein to allow the airflow to circulate within the internal space.

11. The fan unit comprises: The first fan and, a second fan that supplies the airflow to the interior space at a position different from that of the first fan; The opening is 11. The substrate processing apparatus of claim 10, wherein the first fan and / or the second fan is formed on the ground plate at a position overlapping the first fan and / or the second fan when viewed from above.

12. The inner coil and the outer coil are 4. The substrate processing apparatus according to claim 1, wherein the substrate is made of a material containing at least one of copper, aluminum, tungsten, silver, gold, platinum, and iron.

13. The surfaces of the inner coil and the outer coil are 4. The substrate processing apparatus according to claim 1, wherein the substrate is coated with a material containing at least one of silver, gold, and platinum.

14. The ground plate is 4. The substrate processing apparatus according to claim 1, wherein the substrate processing apparatus is made of a material containing at least one of aluminum, copper, and iron.

15. In an apparatus for processing a substrate, a chamber having a processing space; a support unit for supporting a substrate in the processing space; a gas supply unit for supplying a process gas to the processing space; and a plasma generating unit for generating plasma from the process gas, The plasma generating unit comprises: an internal coil section including a plurality of internal coils; an outer coil section provided to surround the inner coil section when viewed from above and including a plurality of outer coils; an upper power supply for applying power to the inner coil section and the outer coil section; The inner coils and the outer coils are provided concentrically with each other, The inner coils and the outer coils each include: a first portion provided in an arc shape having a first radius based on the concentricity; a second portion provided in an arc shape having a second radius based on the concentricity; a third portion provided in an arc shape having a third radius based on the concentricity; a first connecting portion connecting the other end of the first portion and one end of the second portion; a second connecting portion connecting the other end of the second portion and one end of the third portion; the first connecting portion and the second connecting portion are provided so as to be inclined with respect to a straight line passing through the concentric center, One of the first and third parts has a power terminal to which a power line for receiving power from the upper power source is connected, The other of the first and third portions has a ground terminal connected to a ground line, The power terminal and the ground terminal of each of the internal coils and the external coils are located on a straight line passing through the concentric center, a ground plate disposed above the inner coil portion and the outer coil portion; The substrate processing apparatus, wherein the ground terminals of the plurality of internal coils and the plurality of external coils are respectively connected to the ground plate via the ground line.

16. the ground terminal, the power terminal, and the concentric terminal are sequentially arranged on the straight line; a power terminal of one of the internal coils, a power terminal of one of the external coils, and the concentric coils are arranged on the straight line; The straight line passing through the concentricity passes through only one of the first to third parts, 16. The substrate processing apparatus of claim 15, wherein the internal coils and the external coils are all disposed on the same plane.

17. The chamber comprises: The lower body and a cover that is combined with the lower body to form the processing space; an upper body that is combined with the cover to form an internal space in which the inner coil portion and the outer coil portion are disposed; and a fan unit for supplying airflow to the interior space; the ground plate is disposed in the interior space; The ground plate has an opening formed therein to allow the airflow to circulate within the internal space, The fan unit comprises: The first fan and, a second fan that supplies the airflow to the interior space at a position different from that of the first fan; The opening is 16. The substrate processing apparatus of claim 15, wherein the first fan and / or the second fan is formed on the ground plate at a position overlapping the first fan and / or the second fan when viewed from above.

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