Plasma source using planar spiral coil

Abstract

The present invention relates to a plasma source using a planar spiral coil, characterized by comprising: a unit coil extending from a unit extension one end portion and extending in a circular shape in one plane toward a unit extension end portion, and in a plurality of stacks; and a connection portion connecting the unit extension one end portion of another unit coil at the unit extension end portion of one unit coil.

Description

Technical Field

[0001] The present invention relates to a plasma source utilizing a planar helical coil, and more particularly to a plasma source utilizing a planar helical coil, which can form plasma inside a cavity by stacking a plurality of unit coils formed on a plane and connecting the plurality of unit coils by a connecting portion extending in a direction perpendicular to the plane in which the unit coils are formed. Background Technology

[0002] Uniformity is particularly important in semiconductor manufacturing processes, and it can be obtained or adjusted in the etching process.

[0003] Semiconductor etching processes can be performed inside a plasma chamber. The plasma chamber generates plasma within its internal reaction space and uses this plasma to perform the semiconductor etching process.

[0004] Above the plasma chamber is a plasma source for forming plasma. Representative examples of plasma sources include capacitively coupled plasma (CCP) sources and inductively coupled plasma (ICP) sources.

[0005] Capacitively coupled plasma (CCP) sources utilize an electric field and can perform etching at pressures slightly higher than those of inductively coupled plasma (ICP) sources. While CCP sources have slower etching rates, they offer selectivity and excellent process reproducibility.

[0006] However, capacitively coupled plasma (CCP) sources exhibit plasma density inhomogeneity, meaning that the plasma density at the wafer center is relatively higher than that at the wafer edges. Furthermore, due to the lower overall plasma density, high RF power is required to increase the plasma density.

[0007] Inductively coupled plasma (ICP) utilizes an induced magnetic field, resulting in a higher total plasma density compared to capacitively coupled plasma (CCP) sources. ICP can increase etching rates at lower pressures than CCP sources, but the plasma density at the wafer center is relatively higher than at the wafer edges, and it suffers from low selectivity and poor process reproducibility.

[0008] As mentioned above, existing plasma sources have the problem that the plasma density at the center of the wafer is relatively higher than that at the edge of the wafer.

[0009] When the plasma density at the center of the wafer is relatively higher than that at the wafer edge, it is difficult to achieve uniformity at the wafer edge. Therefore, it is necessary to develop a plasma source capable of achieving uniformity at the wafer edge. Summary of the Invention Technical issues

[0010] The present invention aims to solve the above-mentioned problems, and more specifically relates to a plasma source utilizing a planar helical coil, which can form plasma inside a cavity by stacking a plurality of unit coils formed on a plane and connecting the plurality of unit coils by a connecting portion extending in a direction perpendicular to the plane in which the unit coils are formed. Technical solution

[0011] The plasma source of the present invention, which aims to solve the above problems, is characterized in that the plasma source is disposed above a chamber and used to form plasma, the plasma source comprising: a unit coil extending from one end of a unit coil and extending in a circular manner toward the end of the unit coil in a plane, and stacked in a plurality of such coils; and a connecting portion connecting the end of the unit coil of one unit coil to the end of the unit coil of another unit coil.

[0012] In the plasma source utilizing a planar helical coil of the present invention, which aims to solve the above-mentioned problems, the connecting portion can extend vertically toward the plane formed by the unit coil, and the planes formed by the plurality of unit coils extend in parallel directions with each other.

[0013] In the plasma source utilizing a planar helical coil of the present invention, which aims to solve the above-mentioned problems, the length of the connecting portion can be from 5 mm to 15 mm.

[0014] In the plasma source utilizing a planar helical coil of the present invention, which aims to solve the above-mentioned problems, a gap distance may be provided between the unit extension end and the unit extension end portion of the unit coil.

[0015] In the plasma source utilizing planar helical coils of the present invention, which aims to solve the above-mentioned problems, the diameter of the unit coil can be larger than the diameter or width of the wafer placed on the base plate inside the cavity, and the plane formed by the plurality of the unit coils can be located in a direction parallel to the plane on which the wafer is placed.

[0016] In the plasma source utilizing planar helical coils of the present invention, which aims to solve the above-mentioned problems, the directions of the plurality of said unit coils extending from one end of the unit to the extended end of the unit can be the same as each other.

[0017] In the plasma source utilizing a planar helical coil of the present invention, which aims to solve the above-mentioned problems, the plurality of said unit coils may include a first unit coil and a second unit coil, wherein the first unit coil extends from one end of the unit to the extended end portion of the unit in a counterclockwise direction, and the second unit coil extends from one end of the unit to the extended end portion of the unit in a clockwise direction.

[0018] In the plasma source utilizing planar helical coils of the present invention, which aims to solve the above-mentioned problems, the first unit coil and the second unit coil can be stacked alternately.

[0019] In the plasma source utilizing planar helical coils of the present invention, which aims to solve the above-mentioned problems, the second unit coils may be stacked after a plurality of the first unit coils are stacked, or the first unit coils may be stacked after a plurality of the second unit coils are stacked.

[0020] In the plasma source utilizing a planar helical coil of the present invention, which aims to solve the above-mentioned problems, an inner coil may be further included, the diameter of which is smaller than the diameter or width of the wafer of the base plate placed inside the cavity. The inner coil includes a plurality of inner unit coils formed in a circular shape, and the plurality of inner unit coils are arranged on the same plane.

[0021] In the plasma source utilizing a planar helical coil of the present invention, which aims to solve the above-mentioned problems, an internal connection portion may be further included, wherein the internal unit coil extends from one end of the internal unit in a circular manner to the end of the extension of the internal unit, and the internal connection portion connects the end of the extension of the internal unit of one internal unit coil to the end of the extension of the internal unit of another internal unit coil.

[0022] In the plasma source utilizing a planar helical coil of the present invention, which aims to solve the above-mentioned problems, a plurality of the internal connecting portions connecting the internal unit coils can extend in a direction parallel to each other.

[0023] In the plasma source utilizing a planar helical coil of the present invention, which aims to solve the above-mentioned problems, an internal spacing distance may be provided between one end of the inner unit extension of the inner unit coil and the end portion of the inner unit extension.

[0024] In the plasma source utilizing planar helical coils of the present invention, which aims to solve the above-mentioned problems, the plurality of said internal unit coils may include a first internal unit coil and a second internal unit coil, wherein the first internal unit coil extends from one end of the internal unit to the extended end portion of the internal unit in a counterclockwise direction, and the second internal unit coil extends from one end of the internal unit to the extended end portion of the internal unit in a clockwise direction. Beneficial effects

[0025] The present invention relates to a plasma source utilizing planar spiral coils, which can increase the plasma density at the edge of the wafer by stacking a plurality of unit coils with a diameter larger than the diameter or width of the wafer and connecting the plurality of unit coils by a connecting portion extending in a direction perpendicular to the plane formed by the unit coils.

[0026] Furthermore, the present invention can form plasma inside the cavity by equipping a plurality of internal unit coils with a diameter smaller than the diameter or width of the wafer on the same plane and connecting the plurality of internal unit coils by a connecting part, thereby finely adjusting the plasma density at the center of the wafer. Attached Figure Description

[0027] Figure 1 This is a diagram illustrating the stacking of a plurality of unit coils with a diameter greater than the diameter or width of a wafer, according to an embodiment of the present invention.

[0028] Figure 2 This diagram illustrates, according to an embodiment of the present invention, that a plurality of unit coils are connected by a connecting portion extending in a direction perpendicular to the plane forming the unit coil, such that the extension directions of the plurality of unit coils are the same.

[0029] Figure 3 This is a diagram illustrating alternating stacking of first and second unit coils with different extension directions according to an embodiment of the present invention.

[0030] Figure 4 This is a diagram illustrating a second unit coil stacked in a direction different from that of the first unit coil after stacking a plurality of first unit coils according to an embodiment of the present invention.

[0031] Figure 5 This is a diagram illustrating a plurality of internal unit coils with diameters smaller than the wafer diameter or width, arranged in the same plane according to an embodiment of the present invention.

[0032] Figure 6 This diagram illustrates a plurality of internal unit coils formed on the same plane connected by internal connecting portions according to an embodiment of the present invention.

[0033] Figure 7 This is a diagram illustrating the alternating extension of a first internal unit coil and a second internal unit coil with different extension directions according to an embodiment of the present invention.

[0034] Figure 8 This is a diagram illustrating the extension of a second internal unit coil, which extends in a direction different from that of the first internal unit coil, after stacking a plurality of first internal unit coils according to an embodiment of the present invention. Detailed Implementation

[0035] This specification describes the principles of the invention and discloses embodiments to clarify the scope of the invention and enable those skilled in the art to practice the invention. The disclosed embodiments can be implemented in various forms.

[0036] The terms "comprising" or "may include," which can be used in various embodiments of this invention, indicate that the information is disclosed. The presence of such functions, operations, or constituent elements does not limit the possibility of additional functions, operations, or constituent elements. Furthermore, it should be understood that in various embodiments of the invention, terms such as "comprising" or "having" are intended to indicate the presence of features, numbers, steps, operations, constituent elements, components, or combinations thereof described in the specification, without precluding the possibility of the presence or addition of one or more other features, numbers, steps, operations, constituent elements, components, or combinations thereof.

[0037] When describing a component as "connected to" or "combined" with other components, it should be understood that the aforementioned component can be directly connected to or combined with the aforementioned other components, and that new other components may exist between the aforementioned component and the aforementioned other components. Conversely, when describing a component as "directly connected to" or "directly combined" with other components, it should be understood that no new other components exist between the aforementioned component and the aforementioned component.

[0038] The terms "first," "second," etc., used in this specification may be used to describe various constituent elements, but the constituent elements should not be limited by the terms. The terms are only used to distinguish one constituent element from other constituent elements.

[0039] The present invention relates to a plasma source utilizing a planar helical coil, which can generate plasma inside a cavity by stacking a plurality of unit coils formed on a plane and connecting the plurality of unit coils by a connecting portion extending in a direction perpendicular to the plane in which the unit coils are formed.

[0040] In this invention, a plasma source using a planar helical coil is used to generate highly symmetrical and uniform plasma. This plasma source using a planar helical coil can be used for inductively coupled plasma (ICP) with high etching rates and improved reproducibility and selectivity.

[0041] The plasma source using a planar helical coil in this invention can provide a coil with excellent azimuth symmetry. The plasma source using a planar helical coil in this invention increases the pressure inside the cavity, thereby achieving the plasma density inside the cavity in a concave shape.

[0042] The plasma source utilizing a planar helical coil in this invention increases the plasma density inside the cavity from the inner side (center) to the outer side (edge), achieving a concave plasma density within the cavity. Preferred embodiments of the invention will now be described in detail with reference to the accompanying drawings.

[0043] Reference Figure 1 and Figure 2 According to an embodiment of the present invention, a plasma source utilizing a planar helical coil can be positioned above the chamber 10. The chamber 10 is equipped with a base plate 20 for placing a wafer 30, on which an etching process is performed after the wafer 30 is placed.

[0044] An RF generator 21 for applying bias can be integrated into the base plate 20, through which a bias can be applied to the plasma during the etching process.

[0045] The base plate 20 can be arranged in the center of the cavity 10. Since the base plate 20 is arranged in the center of the cavity 10, the wafer 30 can also be arranged in the center of the cavity 10.

[0046] Existing plasma sources exhibit non-uniform plasma density, with high density at the center of chamber 10 and low density at the edges of chamber 10. Therefore, it is difficult to achieve uniformity at the edges of wafer 30.

[0047] To address the aforementioned problems, the plasma source utilizing a planar helical coil according to embodiments of the present invention can provide a coil with excellent azimuth symmetry. The plasma source utilizing a planar helical coil according to embodiments of the present invention can utilize a plasma source including the unit coil 110 and the connecting portion 120. The unit coil 110 and the connecting portion 120 can be external coils 100 arranged outside the wafer 30.

[0048] The unit coil 110 may be composed of a coil through which current flows, and the unit coil 110 extends from one end 11 of the unit. 1. Extends, and extends in a plane toward the end portion 112 in a circular manner. The unit coil 110 extends in a circular manner in a plane, and a plurality of the unit coils 110 may be stacked.

[0049] The unit extension end 111 of the unit coil 110 is the starting point of the unit coil 110 extending in a plane, and the unit extension end 112 is the ending point of the unit coil 110 extending in a plane.

[0050] According to an embodiment of the present invention, a spacing distance 113 may be provided between the unit extension end 111 and the unit extension end portion 112 of the unit coil 110.

[0051] Reference Figure 2 The spacing distance 113 is formed when the end 111 and the end 112 of the unit extension do not contact each other. Since the spacing distance 113 is formed when the end 111 and the end 112 of the unit extension do not contact each other, current can flow in one direction and plasma arcing is prevented.

[0052] According to an embodiment of the present invention, the spacing 113 provided in the plurality of said unit coils 110 may be the same as each other. The diameters of the plurality of said unit coils 110 may be the same as each other, and the plurality of said unit coils 110 may be... In 10, the lengths extending from one end 111 of the unit to the extended end portion 112 of the unit can be the same.

[0053] As described above, in the plurality of said unit coils 110, when the lengths extending from one end 111 of the unit to the end 112 of the unit are the same and the interval distances 113 are the same, the azimuth angles formed in the plurality of said unit coils 110 become the same, thereby the azimuth angles can be symmetrical.

[0054] Reference Figure 2 The connecting part 120 can connect one unit coil 110 and another unit coil 110. The connecting part 120 connects the unit extension end 112 of one unit coil 110 and the unit extension end 111 of another unit coil 110.

[0055] As described above, as the unit coils 110 are stacked, another unit coil 110 can be positioned directly above one unit coil 110. The connecting portion 120 can connect one unit coil 110 and another unit coil 110 positioned directly above the unit coil 110.

[0056] According to an embodiment of the present invention, the connecting portion 120 can extend perpendicularly to the plane formed by the unit coil 110. The plane formed by the plurality of said unit coils 110 can extend in directions parallel to each other.

[0057] That is, refer to Figure 2A plurality of said unit coils 110, forming planes extending in directions parallel to each other, are stacked, and the plurality of said unit coils 110 are connected by said connecting portion 120 perpendicular to the direction in which said unit coils 110 extend.

[0058] The plasma source utilizing a helical coil according to an embodiment of the present invention may further include an RF power generator 140. RF power can be applied to the unit coil 110 through the RF power generator 140, and plasma is formed in the chamber 10 due to changes in the electromagnetic field excited by the unit coil 110.

[0059] According to an embodiment of the present invention, the length of the connecting portion 120 may be 5 mm to 15 mm. Specifically, the length of the connecting portion 120, which connects the unit extension end portion 112 of one unit coil 110 to the unit extension end portion 111 of another unit coil 110, may be 5 mm to 15 mm.

[0060] When the length of the connecting portion 120 is too small (less than 5 mm), interference may occur between the unit coils 110 due to plasma arcing. Therefore, the length of the connecting portion 120 is preferably greater than 5 mm.

[0061] Furthermore, when the length of the connecting portion 120 is too large (greater than 15 mm), plasma flickering or plasma-off may occur between the unit coils 110. Specifically, when the length of the connecting portion 120 is too large, plasma-off may occur. Therefore, plasma cannot be formed through the unit coil 110 if the coil is off. Thus, the length of the connecting portion 120 is preferably less than 15 mm.

[0062] According to an embodiment of the present invention, the diameter of the unit coil 110 may be larger than the diameter or width of the wafer 30 of the base plate 20 placed inside the cavity 10.

[0063] The unit coil 110 can be an external coil arranged outside the wafer 30. When the wafer 30 is placed on the base plate 20, the unit coil 110 can be arranged outside the wafer 30. Therefore, the diameter of the unit coil 110 is preferably larger than the diameter or width of the wafer 30.

[0064] As a plurality of the said unit coils 110 are stacked and thus arranged on the outside of the wafer 30, it is possible to... The plasma density is increased at the edge of 0, thereby preventing the uniformity from decreasing at the edge of wafer 30.

[0065] According to an embodiment of the present invention, the plane formed by the plurality of unit coils 110 can be located in a direction parallel to the plane on which the wafer 30 is placed. When the wafer 30 is placed on the substrate 20, the plane formed by the plate-shaped wafer 30 and the plane formed by the unit coils 110 can extend in directions parallel to each other. Thus, an induced electric field parallel to the surface of the wafer 30 can be formed by the unit coils 11.

[0066] Reference Figure 2 The directions in which the plurality of said unit coils 110 extend from one end 111 of the unit to the extended end portion 112 of the unit may be the same as each other.

[0067] Since the multiple unit coils 110 extend from one end 111 of the unit to the other end 112 of the unit in the same direction, the current can flow in the same direction (clockwise or counterclockwise).

[0068] Reference Figure 3 and Figure 4 According to an embodiment of the present invention, a plurality of unit coils 110 may include a first unit coil 131 and a second unit coil 132, wherein the first unit coil 131 extends from one end 111 of the unit to the unit extension end 112 in a counterclockwise direction, and the second unit coil 132 extends from one end 111 of the unit to the unit extension end 112 in a clockwise direction.

[0069] The winding directions of the first unit coil 131 and the second unit coil 132 are opposite to each other. Since the first unit coil 131 and the second unit coil 132 extend in opposite directions, the current flow can be formed in opposite directions. The direction in which the first unit coil 131 and the second unit coil 132 are wound can be the direction of current flow.

[0070] Specifically, the current flow in the first unit coil 131 can be formed in a counterclockwise direction, and the current flow in the second unit coil 132 can be formed in a clockwise direction.

[0071] Reference Figure 3 The first unit coil 131 and the second unit coil 132 can be stacked alternately. Specifically, The first unit coil 131 and the second unit coil 132 can be stacked alternately, so that current can flow in adjacent unit coils 110 in opposite directions.

[0072] In addition, refer to Figure 4 After a plurality of the first unit coils 131 are stacked, the second unit coil 13 2 can be stacked, or the first unit coil 131 can be stacked after a plurality of the second unit coils 132 have been stacked.

[0073] More specifically, the first unit coil 131 and the second unit coil 132 may not be stacked alternately. Instead, a plurality of the first unit coil 131 and a plurality of the second unit coil 132 are stacked in any order.

[0074] According to an embodiment of the present invention, by adjusting the number of the plurality of said unit coils 110 stacked, and using a plurality of unit coils (the first unit coil 131 and the second unit coil 1) with different winding directions from each other, 32) allows for fine adjustment of plasma density.

[0075] Specifically, by changing the length I of the coils in the plurality of said unit coils 110, a variable inductance L can be obtained, thereby changing the impedance Z. By changing the impedance, the current can be changed, thereby changing the current density J. i Therefore, it is ultimately possible to change the density of the plasma.

[0076] Furthermore, when the first unit coil 131 and the second unit coil 1, with their extending directions opposite to each other, are arranged simultaneously... At 32, the induced electric field parallel to the surface of the wafer 30 changes due to the change in the induced magnetic field, thereby changing the density of the plasma.

[0077] More specifically, depending on which direction the plurality of said unit coils 110 of the same length are wound, the induced electric field parallel to the plane of said wafer 30 can be changed, thereby enabling fine adjustment of the plasma density.

[0078] That is, by changing the length I of the coil according to the number of stacked unit coils 110, the impedance Z and current are changed, thereby adjusting the plasma density. In a coil with a certain length due to the number of stacked unit coils being determined, the induced magnetic field is changed by adjusting the winding direction of the unit coil, thereby changing the induced electric field parallel to the surface of the wafer 30, thereby changing the plasma density.

[0079] The plasma source utilizing a planar helical coil according to an embodiment of the present invention may further include an internal coil 200. The internal coil 200 consists of conductive coils and is equipped with features for finely adjusting the plasma density at the center of the wafer 30.

[0080] According to an embodiment of the present invention, the outer side of the wafer 30 may be equipped with the outer coil 100, and the inner side of the wafer 30 may be equipped with the inner coil 200.

[0081] As described above, by increasing the plasma density at the edge of the wafer 30 using the external coil 100, the uniformity of the wafer 30 can be improved. At the same time, when the internal coil 200 is used simultaneously, the plasma density at the edge of the wafer 30 can be increased while the plasma density at the center of the wafer 30 can be finely adjusted.

[0082] Reference Figure 5 The diameter of the internal coil 200 is smaller than the diameter or width of the wafer 30 of the base plate 20 placed inside the cavity 10, and the internal coil 200 includes a plurality of internal unit coils 210 formed in a circular shape.

[0083] Reference Figure 6 The plurality of said internal unit coils 210 may be arranged on the same plane. Specifically, the plurality of said internal unit coils 210 may be formed in a single layer.

[0084] The internal unit coil 210 may extend from an internal unit at one end 211 in a circular shape and extend to an internal unit extension end 212. The internal unit extension end 211 of the internal unit coil 210 is the starting point of the extension of the internal unit coil 210, and the internal unit extension end 212 is the ending point of the extension of the internal unit coil 210.

[0085] According to an embodiment of the present invention, an internal spacing distance 213 may be provided between the internal unit extension end 211 and the internal unit extension end portion 212 of the internal unit coil 210.

[0086] Reference Figure 6 The internal spacing distance 213 is formed when the inner unit extends from one end 211 and the inner unit extends to the other end 212 without contacting each other.

[0087] Since the internal spacing distance 213 is formed without the internal unit extension end 211 and the internal unit extension end portion 212 contacting each other, current can flow in one direction and plasma arcing can be prevented.

[0088] Reference Figure 6 The internal coil 200 may further include an internal connection portion 220. The internal connection portion 220 may connect one internal unit coil 210 and another internal unit coil 210, and the internal connection portion 220 connects the internal unit extension end portion 212 of one internal unit coil 210 and the internal unit extension end portion 211 of the other internal unit coil 210.

[0089] According to an embodiment of the present invention, the internal coil 200 may include a plurality of internal unit coils 210 formed on the same plane, and the plurality of internal unit coils 210 may be connected by the internal connecting portion 220.

[0090] According to an embodiment of the present invention, the diameter of the plurality of internal unit coils 210 can gradually increase outwards. Specifically, the diameter of the plurality of internal unit coils 210 disposed on a plane can increase from the center to the outside.

[0091] The plurality of internal connecting portions 220 connecting the plurality of internal unit coils 210 may extend in directions parallel to each other. (Refer to...) Figure 6 The plurality of internal connecting portions 220 can extend in parallel directions on the same plane. As a result, the azimuth angles formed in the plurality of internal unit coils 210 are the same, thereby achieving azimuth symmetry.

[0092] The plasma source utilizing a helical coil according to an embodiment of the present invention may further include an internal RF power generator 240. RF power can be applied to the internal unit coil 210 through the internal RF power generator 240, and plasma can be generated by the internal unit coil 210. The change in the electromagnetic field excited by 0 is formed in the chamber 10.

[0093] According to an embodiment of the present invention, a plasma source utilizing a planar spiral coil can increase the plasma density at the edge of the wafer 30 by means of the unit coil 110 formed on a plane and a plurality of stacked outer coils 100.

[0094] According to an embodiment of the present invention, the external coil 100 may be a helical coil with a diameter greater than the diameter or width of the wafer 30. By using the external coil 100, the plasma density inside the chamber 10 in which the wafer 30 is placed may be increased from the inside of the chamber 10 to the outside of the chamber 10.

[0095] According to an embodiment of the present invention, a plasma source utilizing a planar spiral coil can finely adjust the plasma density at the center (inner side) of the chamber 10 by means of a plurality of the internal unit coils 210 arranged on the same plane and the internal coils 200. The internal coils 200 may be spiral coils with a diameter smaller than the diameter or width of the wafer 30.

[0096] When the plasma density is increased from the inside of the chamber 10 to the outside of the chamber 10 by means of the external coil 100, the plasma density at the center of the chamber 10 can be finely adjusted by means of the internal coil 200.

[0097] Specifically, when the plasma density is increased from the inside to the outside of the chamber 10 by the external coil 100, the internal coil 200 can be used to prevent the plasma density at the center of the chamber 10 from decreasing. This improves the uniformity at the center and edges of the wafer 30.

[0098] Reference Figure 6 and Figure 7 According to an embodiment of the present invention, a plurality of internal unit coils 210 may include a first internal unit coil 231 and a second internal unit coil 232. The first internal unit coil 231 extends from an end 211 of the internal unit to an end 212 of the internal unit in a counterclockwise direction, and the second internal unit coil 232 extends from an end 211 of the internal unit to an end 212 of the internal unit in a clockwise direction.

[0099] The first internal unit coil 231 and the second internal unit coil 232 are wound in opposite directions. Because the first internal unit coil 231 and the second internal unit coil 232 extend in opposite directions, the current flow can be formed in opposite directions. The winding direction of the first internal unit coil 231 and the second internal unit coil 232 can be the direction of current flow.

[0100] Specifically, the current flow in the first internal unit coil 231 can be formed in a counterclockwise direction, and the current flow in the second internal unit coil 232 can be formed in a clockwise direction.

[0101] Reference Figure 7 The first internal unit coil 231 and the second internal unit coil 232 can extend alternately. Specifically, the first internal unit coil 231 and the second internal unit coil 232 can be stacked alternately, so that current can flow in adjacent internal unit coils 210 in opposite directions.

[0102] Reference Figure 8 Furthermore, the second internal unit coil 232 may extend after a plurality of the first internal unit coils 231 have extended, or the first internal unit coil 231 may extend after a plurality of the second internal unit coils 232 have extended.

[0103] More specifically, the first internal unit coil 231 and the second internal unit coil 232 may not be stacked alternately, but rather a plurality of the first internal unit coil 231 and a plurality of the second internal unit coil 232 may be stacked in any order.

[0104] According to an embodiment of the present invention, the plasma density can be finely adjusted by using a plurality of internal unit coils (the first internal unit coil 231 and the second internal unit coil 232) with different winding directions.

[0105] The plasma source utilizing a planar helical coil according to the above embodiments of the present invention has the following effects.

[0106] According to an embodiment of the present invention, a plasma source utilizing planar spiral coils is constructed by stacking a plurality of unit coils with diameters larger than the diameter or width of a wafer and connecting the plurality of unit coils by a connecting portion extending in a direction perpendicular to the plane formed by the unit coils.

[0107] According to embodiments of the present invention, the plasma source utilizing planar helical coils has a diameter larger than the diameter or width of the wafer, and it forms plasma inside the cavity by stacking a plurality of unit coils extending in a plane, thereby increasing the plasma density at the wafer edge.

[0108] Furthermore, according to embodiments of the present invention, a plasma source utilizing a planar spiral coil can finely adjust the plasma density inside the chamber by arranging the first and second unit coils, in which the currents flowing in a plurality of unit coils are in the same direction or mixed and arranged so that the currents flow in opposite directions to each other.

[0109] Furthermore, according to embodiments of the present invention, a plasma source utilizing planar spiral coils forms plasma inside a cavity by equipping a plurality of internal unit coils with diameters smaller than the diameter or width of the wafer on the same plane and connecting the plurality of internal unit coils via a connecting portion, thereby allowing for fine adjustment of the plasma density at the center of the wafer.

[0110] According to embodiments of the present invention, a plasma source using a planar helical coil can be used for inductively coupled plasma (ICP), but is not limited thereto; it can be used for various types of plasma.

[0111] As described above, an embodiment of the present invention has been illustrated with reference to the accompanying drawings, but this is exemplary, and those skilled in the art will understand that various modifications and alterations can be made to the embodiment. Therefore, the true scope of protection of the present invention should be determined by the technical concept of the appended claims.

Claims

1. A plasma source utilizing a planar helical coil, characterized in that, A plasma source is positioned above the chamber and used to generate plasma. The plasma source includes: A unit coil, extending from one end of a unit and extending in a circular manner toward the end of the unit in a plane, and in a plurality of stacked units; and A connecting portion, which connects one end of the unit extension of one unit coil to one end of the unit extension of another unit coil. The length of the connecting part is 5 mm to 15 mm. A gap is provided between one end of the unit extension and the other end of the unit extension of the unit coil. The plurality of said unit coils includes a first unit coil and a second unit coil. The first unit coil extends counterclockwise from one end of the unit to the extended end of the unit. The second unit coil extends from one end of the unit to the extended end of the unit in a clockwise direction.

2. The plasma source utilizing a planar helical coil according to claim 1, characterized in that, The connecting portion extends perpendicularly to the plane formed by the unit coil. The planes formed by the plurality of said unit coils extend in parallel directions with each other.

3. The plasma source utilizing a planar helical coil according to claim 1, characterized in that, The diameter of the unit coil is larger than the diameter or width of the wafer placed on the base plate inside the cavity. The plane formed by the plurality of said unit coils is located in a direction parallel to the plane on which the wafer is placed.

4. The plasma source utilizing a planar helical coil according to claim 1, characterized in that, The plurality of said unit coils extend from one end of said unit to the extended end of said unit in the same direction as each other.

5. The plasma source utilizing a planar helical coil according to claim 1, characterized in that, The first unit coil and the second unit coil are stacked alternately.

6. The plasma source utilizing a planar helical coil according to claim 1, characterized in that, After a plurality of the first unit coils are stacked, the second unit coils are stacked. Alternatively, the first unit coil may be stacked after a plurality of the second unit coils have been stacked.

7. A plasma source utilizing a planar helical coil, characterized in that, A plasma source is positioned above the chamber and used to generate plasma. The plasma source includes: External coils, the external coils being a plurality of stacked unit coils extending from one end of a unit and extending in a circular manner toward the end of the unit in a plane; and An internal coil, the diameter of which is smaller than the diameter or width of the wafer placed on the base plate inside the cavity. The internal coil comprises a plurality of internal unit coils formed in a circular shape. A plurality of the aforementioned internal unit coils are arranged on the same plane. The diameter of the outer coil is larger than the diameter or width of the wafer, the outer coil is disposed on the outside of the wafer, and the inner coil is disposed on the inside of the wafer. The internal unit coil extends from one end of the internal unit in a circular shape to the end of the internal unit extension. Furthermore, the plasma source further includes: An internal connection portion, wherein the internal connection portion connects to an end of the internal unit extension of one internal unit coil to an end of the internal unit extension of another internal unit coil.

8. The plasma source utilizing a planar helical coil according to claim 7, characterized in that, The plurality of internal connecting portions connecting the internal unit coils extend in a direction parallel to each other.

9. The plasma source utilizing a planar helical coil according to claim 7, characterized in that, An internal spacing distance is provided between one end of the internal unit extension and the other end of the internal unit extension of the internal unit coil.

10. The plasma source utilizing a planar helical coil according to claim 7, characterized in that, The plurality of said internal unit coils includes a first internal unit coil and a second internal unit coil. The first internal unit coil extends from one end of the internal unit to the extended end of the internal unit in a counterclockwise direction. The second internal unit coil extends from one end of the internal unit to the extended end of the internal unit in a clockwise direction.

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