Self-cleaning inductively coupled plasma source

Abstract

A substrate processing system includes a processing chamber, a plasma source, first and second coils, and a power source. The plasma source is arranged to supply plasma to the processing chamber through a gas distribution device, the gas distribution device being arranged between the processing chamber and the plasma source. The first coil and the second coil are disposed on the plasma source in a staggered manner, and are disposed to ignite a gas supplied to the plasma source to generate the plasma. The power supply is arranged to supply power to the first coil and the second coil in an alternating manner.

Description

[0001] Cross-reference to related applications This application claims priority to U.S. Provisional Application No. 63 / 467,761, filed May 19, 2023. The entire contents of the aforementioned application are incorporated herein by reference. Technical Field

[0002] This disclosure generally relates to substrate processing systems, and more specifically to self-cleaning inductively coupled plasma sources. Background Technology

[0003] The background description provided herein is for the purpose of presenting the general context of this disclosure. The work of the currently designated inventors within the scope described in this background section, as well as aspects of the specification that could not be identified as prior art at the time of filing, are neither express nor implied admissions of prior art to this disclosure.

[0004] Atomic layer deposition (ALD) is a thin film deposition method that sequentially performs gaseous chemical processes to deposit a thin film on a material surface, such as the surface of a substrate (e.g., a semiconductor wafer). Most ALD processes use at least two chemicals called precursors (reactants), which react with the material surface in a sequential and self-limiting manner, one precursor at a time. For example, a typical ALD process involves a series of sequential and repeated feeding and cleaning steps. By repeatedly exposing the material to different precursors, a thin film is gradually deposited on the material surface.

[0005] Plasma-enhanced ALD (PEALD) processes utilize plasma after the feeding step. In some substrate processing systems, the plasma can be generated in situ within the processing chamber. Alternatively, the plasma can be generated and supplied to the processing chamber from outside or away from it. Summary of the Invention

[0006] A substrate processing system includes a processing chamber, a plasma source, a first coil and a second coil, and a power supply. The plasma source is configured to supply plasma to the processing chamber via a gas distribution device disposed between the processing chamber and the plasma source. The first coil and the second coil are alternately arranged on the plasma source and configured to ignite the gas supplied to the plasma source to generate the plasma. The power supply is configured to alternately supply power to the first coil and the second coil.

[0007] In an additional feature, the power source is configured to supply more power to the first coil than to the second coil.

[0008] In an additional feature, the windings of the first coil and the second coil are interleaved.

[0009] In additional features, the first coil is electrically isolated from the second coil.

[0010] In additional features, the substrate processing system further includes a switching circuit connected to the power source. The switching circuit includes a first output connected to the first coil and a second output connected to the second coil. The switching circuit is configured to supply the power from the power source to the first coil and the second coil via the first output and the second output, respectively, in the alternating manner.

[0011] In additional features, the power source is configured to supply a first radio frequency power to the first coil and a second radio frequency power to the second coil.

[0012] In additional features, the first radio frequency power supplied to the first coil is greater than the second radio frequency power supplied to the second coil.

[0013] In additional features, the power source is configured to supply the first radio frequency power to the first coil for a first time period and the second radio frequency power to the second coil for a second time period.

[0014] In additional features, the first time period is greater than the second time period.

[0015] In additional features, the first radio frequency power supplied to the first coil for the first time period is greater than the second radio frequency power supplied to the second coil for the second time period. The first time period is greater than the second time period.

[0016] In additional features, the power source is configured to supply the power to the first coil to generate the plasma.

[0017] In additional features, the power source is configured to supply the power to the second coil to erode material deposited on an inner surface of the plasma source located in a region between windings of the first coil.

[0018] In additional features, the plasma source is dome-shaped, cylindrical, elliptical, or conical.

[0019] In additional features, the plasma source is dome-shaped, cylindrical, elliptical, or conical. The first coil and the second coil are configured around the plasma source.

[0020] In an additional feature, the plasma source is cylindrical and has a first end coupled to the gas distribution device. The first coil and the second coil are configured on a surface located at the second end of the plasma source.

[0021] In an additional feature, the substrate processing system also includes an injector and a base. The injector is coupled to the plasma source. The injector is configured to inject gas into the plasma source to generate the plasma. The base is disposed in the processing chamber to support the substrate. The gas distribution device is configured to filter out ions from the plasma and supply free radicals from the plasma to the processing chamber to process the substrate.

[0022] Among other features, a substrate processing system includes a processing chamber, a plasma source, a coil, and an actuator configured to move the position of the coil on the plasma source. The plasma source is configured to supply plasma to the processing chamber via a gas distribution device disposed between the processing chamber and the plasma source. The coil is disposed on the plasma source and configured to ignite the gas supplied to the plasma source to generate the plasma.

[0023] In an additional feature, the substrate processing system also includes a power source configured to supply power to the coil to ignite the gas. While the power source supplies power to the coil, the actuator is configured to move the position of the coil.

[0024] In an additional feature, the actuator is configured to move the position of the coil to erode material deposited on the inner surface of the plasma source in the region between the windings of the coil.

[0025] In an additional feature, the actuator is configured to move the position of the coil intermittently.

[0026] In an additional feature, the actuator is configured to periodically move the position of the coil.

[0027] In an additional feature, the actuator is configured to cause the coil to repeatedly move between the two positions.

[0028] In an additional feature, the actuator is configured to move the coil linearly between the two positions.

[0029] In an additional feature, the actuator is configured to move the position of the coil by rotating the coil, thereby moving the winding of the coil over different regions of the plasma source.

[0030] In an additional feature, the actuator is configured to move the position of the coil by compressing and decompressing the coil.

[0031] In an additional feature, the actuator is configured to move the position of the coil by periodically vibrating the coil.

[0032] In an additional feature, the plasma source is dome-shaped, cylindrical, elliptical, or conical.

[0033] In an additional feature, the plasma source is dome-shaped, cylindrical, elliptical, or conical. The coil is disposed around the plasma source.

[0034] In an additional feature, the plasma source is cylindrical and has a first end coupled to the gas distribution device. The coil is configured on the surface located at the second end of the plasma source.

[0035] In an additional feature, the substrate processing system also includes an injector and a base. The injector is coupled to the plasma source. The injector is configured to inject gas into the plasma source to generate the plasma. The base is disposed in the processing chamber to support the substrate. The gas distribution device is configured to filter out ions from the plasma and supply free radicals from the plasma to the processing chamber to process the substrate.

[0036] The further scope of the applicability of this disclosure will become apparent from the detailed description, claims, and drawings. The detailed description and specific examples are for illustrative purposes only and are not intended to limit the scope of this disclosure. Attached Figure Description

[0037] This disclosure will be more fully understood in light of the detailed description and accompanying drawings, in which: Figure 1 shows an example of a substrate processing system that includes an inductively coupled plasma (ICP) source; Figure 2 An example of a substrate processing system with dual radio frequency (RF) antennas and a dome-shaped ICP plasma source is shown; Figures 3A and 3B show examples of substrate processing systems with dual RF antennas and cylindrical ICP plasma sources; Figure 4 shows an example of a substrate processing system with dual RF antennas and an elliptical ICP plasma source; Figure 5 shows an example of a substrate processing system with dual RF antennas and a conical ICP plasma source; Figure 6 shows an example of a substrate processing system with a single spatially movable RF antenna and a dome-shaped ICP plasma source; Figures 7A and 7B show examples of substrate processing systems with a single spatially movable RF antenna and a cylindrical ICP plasma source; Figure 8 shows an example of a substrate processing system with a single spatially movable RF antenna and an elliptical ICP plasma source; Figure 9 shows an example of a substrate processing system with a single spatially movable RF antenna and a conical ICP plasma source; Figure 10 shows the operation of a device with dual RF antennas. Figure 2 A method for processing a substrate system of -5; and Figure 11 shows a method for operating the substrate processing system of Figure 6-9 with a single spatially movable RF antenna.

[0038] In the accompanying drawings, reference numerals may be used repeatedly to identify similar and / or identical elements. Detailed Implementation

[0039] Generally, inductively coupled plasma (ICP) sources are not used to deposit conductive films on substrates such as semiconductor wafers. However, compared to other types of plasma sources, ICP sources are attractive candidates for challenging applications, such as depositing conductive films on substrates (e.g., semiconductor wafers), due to the significantly higher plasma density and associated higher radical flux that can typically be achieved.

[0040] ICP plasma sources typically use solid dielectric windows to separate the helical coil antenna excited by radio frequency (RF) power from the plasma generated in the processing chamber. If a conductive film is deposited on a substrate using an ICP plasma source in the processing chamber, the conductive film is also slowly deposited on the dielectric windows located in a region not below the antenna. The deposition of the conductive film on the dielectric windows located in a region not below the antenna is referred to as "window clouding."

[0041] The conductive film deposited on the dielectric window in a region not directly beneath the antenna gradually creates a Faraday cage effect, blocking the electric field from the antenna and interfering with uniform power coupling to the plasma. The main negative impact of blocking the electric field from the antenna and interfering with uniform power coupling to the plasma is process drift. Process drift can cause inhomogeneities in substrate processing, which is highly undesirable in semiconductor fabrication processes.

[0042] Several solutions have been proposed to overcome the problem of unintentional conductive film deposition within ICP plasma sources, which can otherwise hinder inductive coupling through dielectric windows or domes. One solution, for example, is to fully insert the coil (i.e., the antenna) or place it in a vacuum within a processing chamber without dielectric windows. However, in such a configuration, the coil itself sputters onto the substrate being processed within the chamber. Sputtering is unacceptable in certain applications involving conductive film deposition performed using ICP plasma sources.

[0043] This disclosure provides two methods for overcoming window smog. In the first method, a secondary antenna is used. In the second method, a single antenna with spatial mobility is used. These methods are briefly described below, followed by reference to [other methods]. Figure 2 Please provide a detailed explanation.

[0044] Secondary antennas: Sometimes, window turbidity does not occur directly below the antenna. This may be due to localized continuous sputtering near the antenna. If the secondary coil is wound together with the primary antenna and spatially staggered, a scheme can be used where the primary antenna is periodically energized, and alternating secondary antennas are periodically energized. At any given time, most (if not all) of the RF power is applied to only one antenna.

[0045] Spatial movement of the antenna: In this scheme, a single antenna is used and moved slowly, causing the sputtering area to move continuously to effectively clean different parts of the dielectric window. The coil can be moved in different ways depending on the shape of the plasma source (e.g., dome-shaped, cylindrical, elliptical, hemispherical, conical, etc.) and the arrangement of the coil around the plasma source. For example, the coil can rotate about the vertical axis of the plasma source, oscillate about the vertical axis of the plasma source (e.g., compression and decompression), rotate or linearly reciprocate on the top surface of the plasma source (e.g., a cylindrical plasma source), etc.

[0046] This movement can be continuous or intermittent. It can position different portions of the coil at different locations around the plasma source at different times. This movement not only minimizes the deposition of conductive film on the dielectric window but also cleans any residual deposits that may appear on the conductive film on the dielectric window.

[0047] Examples of mechanisms for moving antennas include stepper motors. Antennas can be rotated by rotating the entire electrical system itself (e.g., by rotating the RF power supply and coils). Electro-rotational coupling devices (e.g., electrical slip rings) can also be used to rotate the antenna. Other examples of slip rings include liquid mercury slip rings, ball bearing-based slip rings, and so on.

[0048] The dual-antenna and antenna spatial movement schemes overcome key limitations of conventional ICP plasma sources in conductive film deposition by providing self-cleaning of the dielectric window. For example, in the secondary antenna scheme, when the primary antenna is powered and the secondary antenna is not, material can accumulate on the dielectric window located below the secondary antenna. Then, when the primary antenna is deenergized and the secondary antenna is powered, the accumulation below the secondary antenna is eroded. Similarly, when the secondary antenna is powered and the primary antenna is not, material can accumulate on the dielectric window located below the primary antenna. Then, when the secondary antenna is deenergized and the primary antenna is powered, the accumulation below the primary antenna is eroded. In the spatial movement scheme, when the antenna is moved, any accumulation that may appear between antenna segments is eroded (cleaned).

[0049] In the antenna spatial movement scheme, the movement of the antenna not only minimizes the deposition of conductive film on the dielectric window, but also cleans any residual deposits of conductive film that may have appeared on the dielectric window during substrate processing. These and other features of this disclosure are described in detail below.

[0050] This disclosure is organized as follows. In the first part, an example of a substrate processing system including an ICP plasma source is shown and illustrated with reference to FIG1. ​​In parts 2-5, reference is made to... Figure 2 Figure 6-5 illustrates and explains an example of a substrate processing system comprising dual antennas and ICP plasma sources of different geometries. In sections 6-9, figures 6-9 are used to illustrate and explain an example of a substrate processing system comprising a spatially movable antenna and ICP plasma sources of different geometries. In sections 10 and 11, figures 10 and 11 are used to illustrate and explain a method for operating a substrate processing system having dual antennas and a spatially movable single antenna.

[0051] Part 1: Examples of Substrate Processing Systems Figure 1 shows an example of a substrate processing system 100 including a processing chamber 102, a dual-inflation chamber nozzle 104, and a dome-shaped plasma source 106. The dome shape is shown only as an example. The plasma source 106 may have any other shape as shown in subsequent figures (e.g., elliptical, cylindrical, etc.). In the example shown, the plasma source 106 has a circular base. The plasma source 106 extends upward from the circular base portion having a dome-shaped (e.g., parabolic or conical) profile toward a top central portion. The plasma source 106 comprises a ceramic (e.g., dielectric) material. The plasma source 106 includes an injector 107 located at the top central portion of the plasma source 106.

[0052] The nozzle 104 is made of a metallic material (e.g., aluminum or an alloy). The nozzle 104 is disposed between the plasma source 106 and the processing chamber 102. The nozzle 104 is disposed on top of the processing chamber 102 and at the bottom of the plasma source 106. The nozzle 104 separates the plasma source 106 from the processing chamber 102. The processing chamber 102 is disposed on a first side (i.e., the substrate-facing side) of the nozzle 104. The plasma source 106 is disposed on a second side of the nozzle 104, opposite to the first side of the nozzle 104.

[0053] Processing chamber 102 includes a base 108. During processing, a substrate 110 is disposed on the base 108. An actuator 112 is coupled to a rod portion of the base 108. The actuator 112 is capable of vertically moving the base 108 relative to the nozzle 104 to adjust the gap between the substrate 110 and the nozzle 104.

[0054] The substrate processing system 100 includes a gas delivery system 120 that supplies various gases to the processing chamber 102 and the plasma source 106. For example, during substrate processing, the gas delivery system 120 includes a process gas supply source 122, a purge gas supply source 124, and a precursor supply source 126. The process gas supply source 122 may supply one or more process gases depending on the process performed on the substrate 110. The purge gas supply source 124 may supply one or more process gases (e.g., one or more inert gases). The precursor supply source 126 may supply one or more precursors (reactants) depending on the process performed on the substrate 110.

[0055] Furthermore, although not shown, the gas delivery system 120 may also include a clean gas supply source that can supply one or more clean gases to clean the treatment chamber 102, nozzle 104, and plasma source 106 during preventative maintenance. Additionally, although not shown, each of the process gas supply source 122, purge gas supply source 124, and precursor supply source 126 (and the clean gas supply source) includes a valve and a mass flow controller to control the supply of the respective gas.

[0056] The gas delivery system 120 also includes multiple valves (e.g., valves 130, 132, 134, and 136). A process gas supply source 122 supplies one or more process gases to the injector 107 via valve 130. A purge gas supply source 124 supplies one or more purge gases to the injector 107 via valve 132. A purge gas supply source 124 supplies one or more purge gases to the nozzle 104 via valve 134. A precursor supply source 126 supplies one or more precursors to the nozzle 104 via valve 136.

[0057] Nozzle 104 is a dual-chamber nozzle. Nozzle 104 is generally cylindrical. Nozzle 104 comprises an upper portion 103 and a lower portion 105. The upper portion 103 is cylindrical. The lower portion 105 is annular. Nozzle 104 is a one-piece structure. That is, the upper portion 103 and the lower portion 105 are integrally formed (i.e., a single piece). The upper portion 103 is also referred to as the body of nozzle 104. The body of nozzle 104 (i.e., the upper portion 103) includes an upper surface, a lower surface, and a side surface defining the air chambers in nozzle 104, as described in detail below.

[0058] A plasma source 106 is mounted to the upper portion 103 of the nozzle 104. Specifically, the circular base of the plasma source 106 is mounted to the upper portion 103 of the nozzle 104. The lower portion 105 of the nozzle 104 extends vertically downward from the lower peripheral region of the upper portion 103 of the nozzle 104. The upper portion 103 of the nozzle 104 extends radially outward from the upper region of the lower portion 105 of the nozzle 104 to form a flange 101. The sidewall of the processing chamber 102 is attached to the lower end of the lower portion 105 of the nozzle 104. The flange 101 extends radially outward from the sidewall of the processing chamber 102.

[0059] The outer diameter (OD) of the flange 101 of the nozzle 104 is the same as the OD of the upper portion 103 of the nozzle 104. The OD of the lower portion 105 of the nozzle 104 is the same as the OD of the sidewall of the processing chamber 102. The OD of the upper portion 103 of the nozzle 104 is greater than the OD of the lower portion 105 of the nozzle 104. The inner diameter (ID) of the lower portion 105 of the nozzle 104 is greater than the OD of the base 108. Therefore, the base 108 can be moved vertically up and down by the actuator 112 to adjust the gap between the substrate 110 and the nozzle 104.

[0060] The nozzle 104 includes two air chambers in its upper portion 103. These two air chambers are defined by an upper surface, a lower surface, and a side surface of the upper portion 103 of the nozzle 104. A first air chamber 140 extends radially along the upper portion 103 of the nozzle 104. The first air chamber 140 includes an inlet 121 located on the periphery of the upper portion 103 of the nozzle 104 (e.g., on the flange 101). The first air chamber 140 receives one or more precursors from a precursor supply source 126 via a valve 136 through the inlet 121. The first air chamber 140 includes a plurality of orifices 142-1, 142-2, ..., 142-N (collectively referred to as orifices 142, where N is a positive integer). The first air chamber 140 supplies one or more precursors to the processing chamber 102 via the orifices 142. Therefore, the orifices 142 are also referred to as precursor orifices 142. Inlet 121, first inflation chamber 140 and forebody hole 142 are in fluid communication with each other.

[0061] A precursor aperture 142 extends from the first inflation chamber 140 to the bottom surface of the upper portion 103 of the nozzle 104 (i.e., the surface facing the substrate or the surface facing the processing chamber 102). For convenience, the first inflation chamber 140, which includes the precursor aperture 142, is collectively referred to as the precursor inflation chamber 140. The precursor aperture 142 is radially distributed from the center of the nozzle 104 along the upper portion 103 of the nozzle 104 to the ID of the lower portion 105 of the nozzle 104. The diameter of the first inflation chamber 140 is larger than the diameter of the substrate 110.

[0062] The upper portion 103 of the nozzle 104 includes a second gas chamber containing a plurality of through holes 144-1, 144-2, ..., 144-N (collectively referred to as through holes 144, where N is a positive integer). The through holes 144 extend from the top surface of the upper portion 103 of the nozzle 104 to the bottom surface of the upper portion 103 of the nozzle 104. When plasma 113 is formed in the plasma source 106 as described below, ions from the plasma 113 are filtered out by the through holes 144, while free radicals from the plasma 113 pass through the through holes 144 and enter the processing chamber 102. Therefore, the through holes 144 are also referred to as free radical holes 144. The free radical holes 144 are radially distributed from the center of the nozzle 104 along the upper portion 103 of the nozzle 104 to the ID of the lower portion 105 of the nozzle 104.

[0063] The diameter of the radical orifice 144 is larger than the diameter of the precursor orifice 142. In some implementations, the diameter of the radical orifice 144 may also be smaller, and therefore equal to the diameter of the precursor orifice 142. The radical orifice 144 is not in fluid communication with the first inflation chamber 140 and the precursor orifice 142. For convenience, the radical orifice 144 is collectively referred to as the second inflation chamber 144. The first inflation chamber 140 and the second inflation chamber 144 do not intersect each other (i.e., they are not in fluid communication).

[0064] A coil (also referred to as an antenna) 114 is arranged around the plasma source 106. An RF power supply 116 provides RF power to the coil 114. The RF power supply 116 provides RF power to the coil 114 when process gas is injected into the plasma source 106 through an injector 107. The RF power supplied to the coil 114 activates the process gas to generate plasma 113 in the plasma source 106. A second gas filling chamber 144 (i.e., a radical orifice 144) filters out ions from the plasma 113 and supplies radicals from the plasma 113 to the processing chamber 102.

[0065] The nozzle 104 also includes a cooling channel 146. The cooling channel 146 is disposed within the upper portion 103 of the nozzle 104. The cooling channel 146 is disposed above the first inflation chamber 140 (i.e., the precursor inflation chamber 140). The cooling channel 146 extends radially in the upper portion 103 of the nozzle 104. The fluid delivery system 150 circulates coolant through the cooling channel 146 via inlets and outlets (not shown) located on the periphery of the upper portion 103 of the nozzle 104 (e.g., on the flange 101). The cooling channel 146, the first inflation chamber 140, and the second inflation chamber 144 do not intersect each other (i.e., they are not in fluid communication with each other).

[0066] Although not shown, the base 108 also includes cooling channels. The fluid delivery system 150 also circulates coolant through the cooling channels in the base 108 via inlets and outlets (neither shown) provided on the base 108. The base 108 also includes a heater 109. The heater 109 heats the base 108, which in turn heats the substrate 110. The base 108 includes a temperature sensor 152 to sense the temperature of the base 108. The nozzle 104 also includes a temperature sensor 154 to sense the temperature of the nozzle 104. The system controller 160 controls the heater 109 and the coolant supplied from the fluid delivery system 150 to the base 108 and the nozzle 104 to control the temperatures of the base 108 and the nozzle 104.

[0067] Processing chamber 102 includes multiple exhaust ports (not shown) arranged around the lower periphery of the sidewalls of processing chamber 102. The exhaust ports are coupled to a pre-line coupled to processing chamber 102 via valve 166. Substrate processing system 100 includes a vacuum pump 164 coupled to processing chamber 102 and pre-line 162 via valve 166. Vacuum pump 164 maintains pressure (e.g., vacuum) in processing chamber 102 during substrate processing. Vacuum pump 164 also vents gases (e.g., precursors, process gases, purge gases, etc.) and reaction byproducts from processing chamber 102 during substrate processing and cleaning processes performed during preventative maintenance. System controller 160 controls all components of the substrate processing system 100 described above.

[0068] An example of an ALD cycle that can be performed on substrate 110 in substrate processing system 100, comprising a feeding step and a purging step, will now be described. For example, in the feeding step, a precursor is supplied to processing chamber 102 via precursor filling chamber 142. A purging gas (e.g., an inert gas) is slowly inflowed (i.e. supplied at a low flow rate) into plasma source 106 via injector 107 to maintain positive pressure in plasma source 106.

[0069] Following the batching step is a post-batch cleaning step. In this step, the plasma source 106 and the processing chamber 102 are purged with inert gas. During this step, a thin stream of inert gas is maintained via the plasma source 106, and the cleaning gas is supplied to the processing chamber 102 via the precursor filling chamber 140. In some cases, the flow rate of the cleaning gas via the plasma source 106 can be increased to a level higher than the thin stream.

[0070] Following the dosing and cleaning step is a conversion step. In the conversion step, a process gas (e.g., nitrogen) is supplied to the plasma source 106 via injector 107 at a flow rate greater than a fine stream. Nitrogen can also be provided as a cleaning gas used in the cleaning step of the ALD cycle. RF power supply 116 provides RF power to coil 114, which activates the process gas to excite plasma 113 in plasma source 106. A second filling chamber 144 filters ions from plasma 113 and supplies radicals from plasma 113 to processing chamber 102. The radicals react with precursors deposited earlier on substrate 110 during the dosing step to deposit the desired material (e.g., silicon nitride) on substrate 110.

[0071] Following the conversion step is the second purging step. In the second purging step of the ALD cycle, at the end of the conversion step, RF power supply 116 stops supplying RF power to coil 114, thereby extinguishing plasma 113 in plasma source 106. Plasma source 106 and processing chamber 102 are then purged as described in the post-feeding purging steps above. This cycle of steps is repeated until the desired material thickness is deposited on substrate 110. During the purging steps, vacuum pump 164 expels gases and reaction byproducts from processing chamber 102.

[0072] In some processes, depending on the formulation used to process substrate 110, the same or different precursors may be used in the dosing steps of alternating ALD cycles. For example, a first precursor may be used during the first dosing step of a first ALD cycle, and a second precursor may be used during the second dosing step of a second ALD cycle following the first ALD cycle. These ALD cycles are repeated until the desired thickness of material is deposited on substrate 110.

[0073] As described above, during substrate processing, a material may be deposited in region 111 of the plasma source 106 located between the windings of coil 114. This material may accumulate over time and may create a Faraday cage effect, blocking the electric field from coil 114 and potentially interfering with uniform power coupling to plasma 113. The main negative impact of blocking the electric field from coil 114 and interfering with uniform power coupling to plasma 113 is process drift. Process drift can cause inhomogeneities in substrate processing and is therefore highly undesirable in semiconductor fabrication processes.

[0074] This disclosure provides two methods for minimizing and cleaning unwanted material deposits and build-ups on plasma sources. In the first method, a secondary antenna is used in addition to the primary antenna. In the second method, a single antenna with spatial mobility is used. These methods are described in detail below for plasma sources of various shapes. Throughout the following description, the terms "antenna" and "coil" are used interchangeably and synonymously for elements 114 and 115.

[0075] Part 2: Dual-antenna system—dome-shaped plasma source Figure 2 A substrate processing system 200 comprising dual antennas (two coils) arranged around a dome-shaped plasma source 106 is shown. The substrate processing system 200 is similar to the substrate processing system 100 shown in FIG. 1 because the substrate processing system 200 also includes the dome-shaped plasma source used in the substrate processing system 100. The substrate processing system 200 differs from the substrate processing system 100 because, in addition to the coil 114 (also referred to as the first coil) used in the substrate processing system 100, the substrate processing system 200 also includes a second coil 115. For simplicity, further details are omitted. Figure 2 All elements are labeled with the same reference numerals used in Figure 1. For simplicity, some elements shown in Figure 1 are... Figure 2 The elements are omitted, but it is assumed that they exist.

[0076] Coils 114 and 115 are also referred to as antennas 114 and 115. Coils 114 and 115 together are referred to as a dual-coil or dual-antenna system. Coil 114 may be referred to as the first coil, main coil, first antenna, or primary antenna. Coil 115 may be referred to as the second coil, secondary coil, second antenna, or secondary antenna.

[0077] The first and second coils 114 and 115 are arranged interstitially around the plasma source 106. "Interstitially" means intertwined, entangled, wrapped, or wound in an alternating manner. The first and second coils 114 and 115 are wound together and spatially intertwined. For example, the windings of the first and second coils 114 and 115 alternate as shown. The first and second coils 114 and 115 are not electrically connected to each other. Instead, the first and second coils 114 and 115 are electrically insulated from each other. The winding of the second coil 115 covers region 111 of the plasma source 106 located between the windings of the first coil 114.

[0078] The substrate processing system 200 includes a switching circuit 117. The switching circuit 117 is connected to an RF power supply 116. The switching circuit 117 includes a first output terminal connected to a first coil 114. The switching circuit 117 includes a second output terminal connected to a second coil 115.

[0079] System controller 160 is connected to switching circuit 117. System controller 160 controls switching circuit 117. System controller 160 and switching circuit 117 control the amount and duration of RF power supplied from RF power source 116 to the first and second coils 114, 115. Switching circuit 117 controls the supply of RF power from RF power source 116 to the first and second coils 114, 115. Switching circuit 117 alternately supplies RF power from RF power source 116 to the first and second coils 114, 115; therefore, RF power source 116 supplies RF power to the first and second coils 114, 115 in an alternating manner.

[0080] The RF power supplied to the first coil 114 excites plasma 113 in the processing chamber 102. In contrast, the RF power supplied to the second coil 115 cleans material deposited or accumulated on the inner surface of the plasma source 106 located in the region 111 between the windings of the first coil 114. The RF power supplied to the second coil 115 does not generate plasma in the plasma source 106. Therefore, the switching circuit 117 supplies a smaller amount of RF power to the second coil 115 for a shorter period of time compared to the first coil 114. For example, the RF power supplied to the second coil 115 may be less than 10% or 5% of the RF power supplied to the first coil 114. The switching circuit 117 supplies a larger amount of RF power to the first coil (i.e., the primary antenna 114) for a longer period of time compared to the second coil (i.e., the secondary antenna) 115.

[0081] Generally, switching circuit 117 supplies a first amount of RF power from RF power supply 116 to first coil 114 via a first output terminal. Switching circuit 117 supplies a second amount of RF power from RF power supply 116 to second coil 115 via a second output terminal. The second amount is smaller than the first amount.

[0082] Switching circuit 117 supplies a first level of RF power to first coil 114 during a first time period. Switching circuit 117 supplies a second level of RF power to second coil 115 during a second time period. The second time period is shorter than the first time period.

[0083] The magnitude of the supplied RF power and the duration for which the RF power is supplied to the first and second coils 114, 115 via the switching circuit 117 can be different. The switching circuit 117 can use different combinations of the magnitude of the supplied RF power and the duration for which these magnitudes of RF power are supplied to the first and second coils 114, 115.

[0084] At any given time, switching circuit 117 supplies most (e.g., 90% or 95%) of the RF power from RF power supply 116 to only one antenna (e.g., the first coil or primary antenna 114). By supplying RF power to the second coil (i.e., the secondary antenna) 115, material deposits and accumulations in region 111 of plasma source 106 below the windings of the second coil (i.e., the secondary antenna) 115 can be minimized and / or removed. Therefore, process drift that might otherwise be caused by material accumulations in region 111 of plasma source 106 is minimized or eliminated, and non-uniformities in substrate processing are avoided.

[0085] Part 3: Dual-antenna system—cylindrical plasma source Figure 3A shows a substrate processing system 300 comprising dual antennas (two coils) arranged on a cylindrical plasma source 106. The substrate processing system 300 is similar to [other systems] except that it includes a cylindrical plasma source instead of a dome-shaped plasma source. Figure 2 The substrate processing system 200 is shown. First and second coils 114 and 115 are arranged laterally on the top surface of a cylindrical plasma source 106. The first and second coils 114 and 115 are arranged horizontally on the top surface of the cylindrical plasma source 106, located in a plane parallel to the plane containing the upper portion 103 of the nozzle 104. The top surface of the cylindrical plasma source 106 is opposite to the bottom surface of the cylindrical plasma source 106 to which the upper portion 103 of the nozzle 104 is attached.

[0086] With Figure 2As in the substrate processing system 200 shown, the first and second coils 114 and 115 are co-wound and spatially interleaved. The first and second coils 114 and 115 are arranged alternately on the top surface of the cylindrical plasma source 106. For example, as shown, the windings of the first and second coils 114 and 115 alternate. The winding of the second coil 115 covers the region 111 on the top surface of the cylindrical plasma source 106 located between the windings of the first coil 114.

[0087] For the sake of brevity, all elements in Figure 3A that are labeled with the same reference numerals used in Figures 1 and 2 will not be described further. For simplicity, some elements shown in Figure 1 are omitted in Figure 3A, but it is assumed that these elements are present. As referenced above... Figure 2 As described above, the switching circuit 117 controls the RF power supplied from the RF power supply 116 to the first and second coils 114 and 115. Therefore, for the sake of brevity, this description will not be repeated.

[0088] Furthermore, at any given time, most of the RF power from RF power source 116 is applied to only one antenna (e.g., the first coil or primary antenna 114). By supplying RF power to the second coil (i.e., the secondary antenna) 115, material deposits and accumulations in region 111 on the top surface of the cylindrical plasma source 106 below the windings of the second coil (i.e., the secondary antenna) 115 can be minimized and / or eliminated. Therefore, process drift that might otherwise be caused by material accumulations in region 111 on the top surface of the cylindrical plasma source 106 is minimized or eliminated, and non-uniformities in substrate processing are avoided.

[0089] Figure 3B shows a substrate processing system 300-1 comprising dual antennas (two coils) arranged on a cylindrical plasma source 106. Substrate processing system 300-1 differs from substrate processing system 300 shown in Figure 3A because it includes an alternating arrangement of first and second coils 114, 115 on the cylindrical plasma source 106. Specifically, in substrate processing system 300-1, the first and second coils 114, 115 are not arranged on the top surface of the cylindrical plasma source 106. Instead, in substrate processing system 300-1, the first and second coils 114, 115 are arranged around the sidewalls of the cylindrical plasma source 106. The first and second coils 114, 115 are vertically arranged on the sidewalls of the cylindrical plasma source 106 along a vertical axis perpendicular to the plane containing the upper portion 103 of the nozzle 104. Otherwise, substrate processing system 300-1 is similar to substrate processing system 300 shown in Figure 3A.

[0090] With Figure 2Similar to the substrate processing systems 200 and 300 shown in 3A, the first and second coils 114 and 115 are co-wound and spatially interleaved. The first and second coils 114 and 115 are arranged alternately around the sidewalls of the cylindrical plasma source 106. For example, as shown, the windings of the first and second coils 114 and 115 alternate. The winding of the second coil 115 covers the region 111 on the sidewall of the cylindrical plasma source 106 located between the windings of the first coil 114.

[0091] For the sake of brevity, all elements labeled with the same reference numerals used in Figures 1, 2, and 3A in Figure 3B will not be described further. For simplicity, some elements shown in Figure 1 are omitted in Figure 3B, but it is assumed that these elements are present. As referenced above... Figure 2 As described above, the switching circuit 117 controls the RF power supplied from the RF power supply 116 to the first and second coils 114 and 115. Therefore, for the sake of brevity, this description will not be repeated.

[0092] Similarly, at any given time, most of the RF power from RF power source 116 is applied to only one antenna (e.g., the first coil or primary antenna 114). By supplying RF power to the second coil (i.e., the secondary antenna) 115, material deposits and accumulations in region 111 on the sidewall of the cylindrical plasma source 106 below the windings of the second coil (i.e., the secondary antenna) 115 can be minimized and / or removed. Therefore, process drift that might otherwise be caused by material accumulations in region 111 on the top sidewall of plasma source 106 is minimized or eliminated, and non-uniformities in substrate processing are avoided.

[0093] Part 4: Dual-antenna system—elliptical plasma source Figure 4 shows a substrate processing system 400 comprising dual antennas (two coils) arranged around an elliptical plasma source 106. The substrate processing system 400 is similar to [other systems] except that it includes an elliptical plasma source instead of a dome-shaped or cylindrical plasma source. Figure 2 Substrate processing systems 200, 300, and 300-1 are shown in 3A and 3B, respectively. In substrate processing system 400, first and second coils 114 and 115 are arranged around elliptical plasma source 106.

[0094] With Figure 2Similar to the substrate processing systems 200, 300, and 300-1 shown in Figures 3A and 3B, the first and second coils 114 and 115 are co-wound and spatially interleaved. The first and second coils 114 and 115 are arranged alternately around the elliptical plasma source 106. For example, as shown, the windings of the first and second coils 114 and 115 alternate. The winding of the second coil 115 covers region 111 of the elliptical plasma source 106 located between the windings of the first coil 114.

[0095] For the sake of brevity, all elements labeled with the same reference numerals used in Figures 1, 2, 3A, and 3B in Figure 4 will not be described further. For simplicity, some elements shown in Figure 1 are omitted in Figure 4, but it is assumed that these elements are present. (Refer to the above...) Figure 2 As described above, the switching circuit 117 controls the RF power supplied from the RF power supply 116 to the first and second coils 114 and 115. Therefore, for the sake of brevity, this description will not be repeated.

[0096] Similarly, at any given time, most of the RF power from RF power source 116 is applied to only one antenna (e.g., the first coil or primary antenna 114). By supplying RF power to the second coil (i.e., the secondary antenna) 115, material deposits and accumulations in region 111 of the elliptical plasma source 106 below the windings of the second coil (i.e., the secondary antenna) 115 can be minimized and / or eliminated. Therefore, process drift that might otherwise be caused by material accumulations in region 111 of the elliptical plasma source 106 is minimized or eliminated, and non-uniformities in substrate processing are avoided.

[0097] Part 5: Dual-antenna system—conical plasma source Figure 5 shows a substrate processing system 500 comprising dual antennas (two coils) arranged around a conical plasma source 106. The substrate processing system 500 is similar to [other systems described above] except that it includes a conical plasma source instead of a dome-shaped, cylindrical, or elliptical plasma source. Figure 2 Substrate processing systems 200, 300, 300-1, and 400 are shown in 3A, 3B, and 4. In substrate processing system 500, first and second coils 114 and 115 are arranged around a conical plasma source 106.

[0098] With Figure 2Similar to the substrate processing systems 200, 300, 300-1, and 400 shown in Figures 3A, 3B, and 4, the first and second coils 114 and 115 are co-wound and spatially interleaved. The first and second coils 114 and 115 are arranged alternately around the conical plasma source 106. For example, as shown, the windings of the first and second coils 114 and 115 alternate. The winding of the second coil 115 covers region 111 of the conical plasma source 106 located between the windings of the first coil 114.

[0099] For the sake of brevity, all elements labeled with the same reference numerals used in Figures 1, 2, 3A, 3B, and 4 will not be described in Figure 5. For simplicity, some elements shown in Figure 1 are omitted in Figure 5, but it is assumed that these elements are present. (Refer to the above...) Figure 2 As described above, the switching circuit 117 controls the RF power supplied from the RF power supply 116 to the first and second coils 114 and 115. Therefore, for the sake of brevity, this description will not be repeated.

[0100] Similarly, at any given time, most of the RF power from RF power source 116 is applied to only one antenna (e.g., the first coil or primary antenna 114). By supplying RF power to the second coil (i.e., the secondary antenna) 115, material deposits and accumulations in region 111 of the conical plasma source 106 below the windings of the second coil (i.e., the secondary antenna) 115 can be minimized and / or eliminated. Therefore, any process drift that might otherwise be caused by material accumulations in region 111 of the conical plasma source 106 is minimized or eliminated, and non-uniformities in substrate processing are avoided.

[0101] Part 6: Single Antenna System—Dome-shaped Plasma Source Figure 6 shows a substrate processing system 600 comprising a single antenna (single coil) 114 arranged around a dome-shaped plasma source 106. The substrate processing system 600 is similar to the substrate processing system 100 shown in Figure 1 because it also includes the dome-shaped plasma source used in the substrate processing system 100. The substrate processing system 600 differs from the substrate processing system 100 because it includes a coil moving system 119 for moving the coil 114. The coil moving system 119 is described in detail below. For simplicity, all elements labeled with the same reference numerals used in Figure 1 are not described in Figure 6. For simplification, some components shown in Figure 1 are omitted in Figure 6, but it is assumed that these components are present.

[0102] Coil movement system 119 is connected to coil 114. System controller 160 is connected to coil movement system 119. System controller 160 controls coil movement system 119. Coil movement system 119 moves or displaces coil 114 between two positions located on or around the surface of dome-shaped plasma source 106. For example, these two positions may be referred to as a first position and a second position. For example, these two positions may be referred to as an initial position and a displaced position. In Figures 6-9, coil 114 is shown using solid lines to indicate the first position of coil 114. Coil 114 is shown using dashed lines to indicate the second (displaced) position of coil 114.

[0103] For example, coil movement system 119 moves coil 114 from a first position to a second position. Then, coil movement system 119 moves coil 114 from the second position to the first position. Coil movement system 119 repeatedly moves coil 114 between the first and second positions (e.g., oscillates, dithers (i.e., moves intermittently or randomly), or vibrates). For example, coil movement system 119 may periodically vibrate coil 114, or intermittently move coil 114 to random positions between the first and second positions. Coil movement system 119 may periodically or continuously move coil 114 between the first and second positions.

[0104] When the coil moving system 119 moves or displaces the coil 114 from a first position to a second position, the windings of the coil 114 move to regions 111 of the dome-shaped plasma source 106, which are located between the windings of the coil 114 when the coil 114 is in the first position. The coil moving system 119 moves the coil 114 when the RF power supply 116 supplies RF power to it. By moving the coil 114 between the first and second positions while RF power is supplied to it, material deposits and accumulations in regions 111 of the dome-shaped plasma source 106 can be minimized and / or removed.

[0105] The coil moving system 119 can move or displace the coil 114 in many ways. The coil moving system 119 may include different types of actuators coupled to the coil 114 to move or displace the coil 114 in different ways. For example, the coil moving system 119 may include a stepper motor connected to the outermost winding of the coil 114. The stepper motor can repeatedly push and pull (e.g., compress and decompress) the coil 114.

[0106] In some examples, although not shown, the coil moving system 119 may include a first stepper motor and a second stepper motor, the first stepper motor being connected to the uppermost winding of the coil 114 and the second stepper motor being connected to the lowermost winding of the coil 114. The first and second stepper motors can move the coil 114 as follows.

[0107] For example, a first stepper motor connected to the uppermost winding can push coil 114 down (towards nozzle 104), while a second stepper motor connected to the lowermost winding can pull coil 114 down (towards nozzle 104). In some examples, a first stepper motor connected to the uppermost winding can push coil 114 down (towards nozzle 104), while a second stepper motor connected to the lowermost winding can push coil 114 up (away from nozzle 104).

[0108] The coil movement system 119 can repeat the push-pull actions of the first and second stepper motors. The coil movement system 119 can control the first and second stepper motors to perform different combinations of push-pull actions. The coil movement system 119 can use any combination of the above movements to move or displace the coil 114 between two or more positions. Furthermore, the coil movement system 119 can repeat these movements in any order. In some examples, these movements can be random. Using these movements, the winding of the coil 114 is displaced and contacts different regions (e.g., region 111) on the inner surface or periphery of the dome-shaped plasma source 106. The coil movement system 119 can move the coil 114 periodically or continuously.

[0109] In other examples, the coil moving system 119 may include a rotation system that rotates the coil 114 about a surface or periphery of the dome-shaped plasma source 106. For example, the rotation system of the coil moving system 119 rotates the coil 114 about a vertical axis perpendicular to the plane containing the upper portion 103 of the nozzle 104. By rotating the coil 114, the windings of the coil 114 are displaced and contact different regions (e.g., region 111) on the inner surface or periphery of the dome-shaped plasma source 106.

[0110] For example, the rotation system of the coil moving system 119 can rotate the coil 114 clockwise about a vertical axis to a first position. Then, the rotation system of the coil moving system 119 can rotate the coil 114 counterclockwise about a vertical axis to a second position. The rotation system of the coil moving system 119 can repeatedly move the coil 114 between the first and second positions. The rotation system of the coil moving system 119 can periodically or continuously move the coil 114 between the first and second positions.

[0111] In some examples, the rotation system of the coil movement system 119 can rotate the coil 114 by rotating the entire electrical system (e.g., by rotating the RF power supply 116 and the coil 114). In other examples, the rotation system of the coil movement system 119 can use an electro-rotational coupling device (e.g., an electric slip ring) to rotate the coil 114. Other examples of electric slip rings include liquid mercury slip rings, ball bearing-based slip rings, and so on. The linear and rotational mechanisms of the coil movement system 119 that linearly moves and rotates the coil 114 as described above can be collectively referred to as the actuator of the coil movement system 119 that moves the coil 114.

[0112] In the example above, when the RF power supply 116 supplies RF power to the coil 114, the coil moving system 119 moves the coil 114. By moving the coil 114 when RF power is supplied to it, material deposits and accumulations in the region 111 of the dome-shaped plasma source 106 located between the windings of the coil 114 can be minimized and / or removed. Therefore, process drift that might otherwise be caused by material accumulations in the region 111 of the dome-shaped plasma source 106 is minimized or eliminated, and non-uniformities in substrate processing are avoided.

[0113] Part 7: Single Antenna System—Cylindrical Plasma Source Figure 7A shows a substrate processing system 700 comprising a single antenna (single coil) 114 arranged on a cylindrical plasma source 106. The substrate processing system 700 is similar to the substrate processing system 600 shown in Figure 6, except that it includes a cylindrical plasma source instead of a dome-shaped plasma source. For simplicity, all elements labeled with the same reference numerals used in Figures 1 and 6 are not described in Figure 7A. For simplification, some elements shown in Figure 1 are omitted in Figure 7A, but it is assumed that these elements are present.

[0114] Coils 114 are arranged laterally on the top surface of the cylindrical plasma source 106. The coils 114 are arranged horizontally on the top surface of the cylindrical plasma source 106 in a plane parallel to the plane containing the upper portion 103 of the nozzle 104. The top surface of the cylindrical plasma source 106 is opposite to the bottom surface of the cylindrical plasma source 106 to which the upper portion 103 of the nozzle 104 is attached.

[0115] The coil movement system 119 can move or displace the coil 114 laterally along a plane parallel to the plane containing the upper portion 103 of the nozzle 104. For example, one or two stepper motors can move (displace) the coil 114 linearly along a plane parallel to the plane containing the upper portion 103 of the nozzle 104. Alternatively, the coil movement system 119 can rotate the coil 114 about a vertical axis perpendicular to the plane containing the upper portion 103 of the nozzle 104. As described above with reference to FIG. 6, the coil movement system 119 can move the coil 114 linearly or by rotating the coil 114 in different ways. Therefore, for the sake of brevity, this description will not be repeated. By moving the coil 114 laterally or by rotating the coil 114, the winding of the coil 114 is displaced and contacts different regions (e.g., region 111) on the top inner surface of the cylindrical plasma source 106.

[0116] When the RF power supply 116 supplies RF power to the coil 114, the coil moving system 119 moves the coil 114 (laterally or by rotating the coil 114). By moving the coil 114 while RF power is supplied to it, material deposits and accumulations in region 111 on the top surface of the cylindrical plasma source 106 can be minimized and / or removed. Therefore, any process drift that might otherwise be caused by material accumulations in region 111 on the top surface of the cylindrical plasma source 106 is minimized or eliminated, and non-uniformities in substrate processing are avoided.

[0117] Figure 7B shows a substrate processing system 700-1 comprising a single antenna (single coil) 114 arranged on a cylindrical plasma source 106. Substrate processing system 700-1 differs from substrate processing system 700 shown in Figure 7A because it comprises an alternating arrangement of the first coil 114 located on the cylindrical plasma source 106. Specifically, in substrate processing system 700-1, the first coil 114 is not arranged on the top surface of the cylindrical plasma source 106. Instead, in substrate processing system 700-1, the coil 114 is arranged around the sidewalls of the cylindrical plasma source 106. The coil 114 are arranged vertically on the sidewalls of the cylindrical plasma source 106 along an axis perpendicular to the plane containing the upper portion 103 of the nozzle 104. Otherwise, substrate processing system 700-1 is similar to substrate processing system 700 shown in Figure 7A. For simplicity, all elements labeled with the same reference numerals used in Figures 1, 6, and 7A are not described further in Figure 7B. For the sake of simplicity, some of the elements shown in Figure 1 are omitted in Figure 7B, but it is assumed that these elements are present.

[0118] The coil movement system 119 can linearly move or displace the coil 114 along a vertical axis perpendicular to the plane containing the upper portion 103 of the nozzle 104. For example, one or two stepper motors can linearly move (displace) the coil 114 along a vertical axis perpendicular to the plane containing the upper portion 103 of the nozzle 104. Alternatively, the coil movement system 119 can rotate the coil 114 about a vertical axis perpendicular to the plane containing the upper portion 103 of the nozzle 104. As described above with reference to FIG. 6, the coil movement system 119 can linearly move the coil 114 or move the coil by rotating it in different ways. Therefore, for the sake of brevity, this description will not be repeated. By moving the coil 114 laterally or by rotating the coil 114, the winding of the coil 114 is displaced and contacts different regions (e.g., region 111) on the sidewall of the cylindrical plasma source 106.

[0119] As the RF power supply 116 supplies RF power to the coil 114, the coil moving system 119 moves the coil 114 (laterally or by rotating the coil 114). By moving the coil 114 while RF power is supplied to it, material deposits and accumulations in region 111 on the sidewall of the cylindrical plasma source 106 can be minimized and / or removed. Therefore, any process drift that might otherwise be caused by material accumulations in region 111 on the top surface of the cylindrical plasma source 106 is minimized or eliminated, and non-uniformities in substrate processing are avoided.

[0120] Part 8: Single Antenna System—Elliptical Plasma Source Figure 8 shows a substrate processing system 800 comprising a single antenna (single coil) 114 arranged around an elliptical plasma source 106. The substrate processing system 800 is similar to the substrate processing systems 600, 700, and 700-1 shown in Figures 6, 7A, and 7B, except that it includes an elliptical plasma source instead of a dome-shaped or cylindrical plasma source. In the substrate processing system 800, the coil 114 is arranged around the elliptical plasma source 106. For simplicity, all elements labeled with the same reference numerals used in Figures 1, 6, 7A, and 7B are not described further in Figure 8. For simplification, some elements shown in Figure 1 are omitted in Figure 8, but it is assumed that these elements are present.

[0121] As described above with reference to FIG. 6, the coil moving system 119 can move or displace the coil 114 along the surface or periphery of the elliptical plasma source 106 in different ways. Alternatively, as described above with reference to FIG. 6, the coil moving system 119 can rotate the coil 114 in different ways. Therefore, for the sake of brevity, this description will not be repeated. By moving or rotating the coil 114, the windings of the coil 114 are displaced and contact different regions (e.g., region 111) on the surface of the elliptical plasma source 106.

[0122] When RF power is supplied to coil 114 by RF power source 116, coil moving system 119 moves or rotates coil 114. By moving or rotating coil 114 when RF power is supplied to it, material deposits and accumulations in region 111 of elliptical plasma source 106 can be minimized and / or removed. Therefore, any process drift that might otherwise be caused by material accumulations in region 111 of elliptical plasma source 106 is minimized or eliminated, and non-uniformity in substrate processing is avoided.

[0123] Part 9: Single Antenna System—Conical Plasma Source Figure 9 shows a substrate processing system 900 comprising a single antenna (single coil) 114 arranged around a conical plasma source 106. The substrate processing system 900 is similar to the substrate processing systems 600, 700, 700-1, and 800 shown in Figures 6, 7A, 7B, and 800, except that it includes a conical plasma source instead of a dome-shaped, cylindrical, or elliptical plasma source. In the substrate processing system 900, the coil 114 is arranged around the conical plasma source 106. For simplicity, all elements labeled with the same reference numerals used in Figures 1, 6, 7A, 7B, and 8 are not described in Figure 9. For simplification, some elements shown in Figure 1 are omitted in Figure 9, but it is assumed that these elements are present.

[0124] As described above with reference to FIG. 6, the coil moving system 119 can move or displace the coil 114 along the surface or periphery of the conical plasma source 106 in different ways. Alternatively, as described above with reference to FIG. 6, the coil moving system 119 can rotate the coil 114 in different ways. Therefore, for the sake of brevity, this description will not be repeated. By moving or rotating the coil 114, the windings of the coil 114 are displaced and contact different regions (e.g., region 111) on the inner surface of the conical plasma source 106.

[0125] When RF power is supplied to coil 114 by RF power source 116, coil moving system 119 moves or rotates coil 114. By moving or rotating coil 114 when RF power is supplied to it, material deposits and accumulations in region 111 of cone plasma source 106 can be minimized and / or removed. Therefore, any process drift that might otherwise be caused by material accumulations in region 111 of cone plasma source 106 is minimized or eliminated, and non-uniformities in substrate processing are avoided.

[0126] Part 10: Control Methods—Dual Antenna System Figure 10 shows the control of the above reference. Figure 2 -5 shows and describes the method 1000 for dual antennas (coils 114, 115). For example, the above references Figure 2 The system controller 160 and switching circuit 117 shown in Figure 5 can execute method 1000.

[0127] In 1002, as referenced above. Figure 2 As described in Figure 5, the two coils 114 and 115 are spatially interleaved around the plasma source 106. At 1004, the substrate 110 is loaded into the processing chamber 102. At 1006, in order to process the substrate 110 in the processing chamber 102, as described above with reference to FIG. 1, the gas delivery system 120 supplies processing gas to the plasma source 106.

[0128] In 1008, as referenced above. ​ As described in section -5, system controller 160 and switching circuit 117 control the RF power supplied to the two coils 114 and 115. The RF power supplied to coil 114 ignites the gas in plasma source 106 and excites plasma 113 in plasma source 106 to deposit material on substrate 110. The RF power supplied to coil 115 minimizes and / or removes any material deposits located in region 111 of plasma source 106. At 1010, using plasma 113, material is deposited on substrate 110.

[0129] Part 11: Control Methods—Single Antenna System Figure 11 shows a method 1100 for controlling the single antenna (coil 114) shown and described above with reference to Figures 6-9. For example, the system controller 160 and coil movement system 119 shown and described above can perform method 1100.

[0130] At 1102, as described above with reference to Figures 6-9, coils 114 are arranged around plasma source 106. At 1104, substrate 110 is loaded into processing chamber 102. At 1106, in order to process substrate 110 in processing chamber 102, gas delivery system 120 supplies processing gas to plasma source 106 as described above with reference to Figure 1.

[0131] At 1108, as described above with reference to Figures 6-9, RF power supply 116 supplies RF power to coil 114. The RF power supplied to coil 114 ignites the gas in plasma source 106 and excites plasma 113 in plasma source 106 to deposit material on substrate 110. At 1110, as described above with reference to Figures 6-9, system controller 160 and coil movement system 119 intermittently or continuously move coil 114 around plasma source 106. When using plasma 113 to deposit material on substrate 110, the movement of coil 114 minimizes and / or removes any material deposits in region 111 of plasma source 106.

[0132] The foregoing description is merely illustrative in nature and is in no way intended to limit this disclosure, its application, or its use. The broad teachings of this disclosure can be implemented in various forms. Therefore, while this disclosure includes specific examples, its true scope should not be so limited, as other modifications will become apparent upon examination of the drawings, specification, and appended claims.

[0133] It should be understood that one or more steps in the method may be performed in a different order (or simultaneously) without altering the principles of this disclosure. Furthermore, while each example is described above as having certain features, any one or more of those features described relative to any example of this disclosure may be implemented in and / or combined with features of any other example, even if such combination is not explicitly described. In other words, the described examples are not mutually exclusive, and the substitution of one or more examples for each other remains within the scope of this disclosure.

[0134] Various terms are used to describe spatial and functional relationships between elements (e.g., between modules, between circuit elements, between semiconductor layers, etc.), including “connection,” “joint,” “coupled,” “adjacent,” “next to,” “on top of,” “above,” “below,” and “set.” Unless the relationship between the first and second elements is explicitly described as “direct,” the relationship described in the above disclosure can be a direct relationship, where no other intermediate element exists between the first and second elements, but it can also be an indirect relationship, where one or more intermediate elements exist between the first and second elements (spatially or functionally). As used herein, the phrase “at least one of A, B, and C” should be interpreted as meaning the use of a non-exclusive logical OR (A or B or C) logic and should not be interpreted as meaning “at least one of A, at least one of B, and at least one of C.”

[0135] In some implementations, the controller is part of a system, which may be part of the examples described above. Such a system may include semiconductor processing equipment, which includes one or more processing tools, one or more chambers, one or more platforms for processing, and / or specific processing components (wafer pedestals, gas flow systems, etc.). These systems may be integrated with electronics for controlling their operation before, during, and after the processing of semiconductor wafers or substrates. These electronics may be referred to as a "controller," which can control various components or sub-components of one or more systems.

[0136] Depending on the processing requirements and / or system type, the controller can be programmed to control any process disclosed herein, including process gas delivery, temperature settings (e.g., heating and / or cooling), pressure settings, vacuum settings, power settings, radio frequency (RF) generator settings, RF matching circuit settings, frequency settings, flow rate settings, fluid delivery settings, position and operation settings, wafer transfer tools and other transfer tools, and / or loading locks that are connected to or docked with a specific system.

[0137] In a broad sense, a controller can be defined as an electronic device that has various integrated circuits, logic, memory, and / or software for receiving instructions, issuing instructions, controlling operations, enabling cleaning operations, enabling endpoint measurements, etc. Integrated circuits can include chips in the form of firmware that store program instructions, digital signal processors (DSPs), chips defined as application-specific integrated circuits (ASICs), and / or one or more microprocessors or microcontrollers that execute program instructions (e.g., software).

[0138] Program instructions can be sent to the controller in the form of various individual settings (or program files), which define the operating parameters for performing a specific process on or for a semiconductor wafer or system. In some examples, the operating parameters may be part of a recipe defined by a process engineer to complete one or more processing steps during the fabrication of one or more layers, materials, metals, oxides, silicon, silicon dioxide, surfaces, circuits, and / or wafer dies.

[0139] In some implementations, the controller may be part of or coupled to a computer that is integrated with, coupled to, or otherwise networked to the system. For example, the controller may be in the "cloud" or be a whole or part of a fab host system, allowing remote access to wafer processing. The computer can then remotely access the system to monitor the current progress of manufacturing operations, examine the history of past manufacturing operations, check trends or performance standards of multiple manufacturing operations, change parameters of the current process, set processing steps to follow the current process, or initiate a new process.

[0140] In some examples, a remote computer (e.g., a server) can provide process recipes to the system via a network (which may include a local network or the Internet). The remote computer may include a user interface that enables the input or programming of parameters and / or settings, which are then transmitted from the remote computer to the system. In some examples, the controller receives instructions in the form of data specifying parameters for each processing step to be performed during one or more operations. It should be understood that the parameters may be specific to the type of process to be performed and the type of tool to which the controller is configured to interface with or control the tool.

[0141] Therefore, as described above, a controller can be distributed, for example, by comprising one or more discrete controllers networked together and operating toward a common purpose (such as the process and control described herein). An example of a distributed controller for such a purpose is one or more integrated circuits on-site communicating with one or more integrated circuits remotely (e.g., at the platform level or as part of a remote computer), which together control the process on-site.

[0142] Example systems may include, but are not limited to, plasma etching chambers or modules, deposition chambers or modules, rotary rinsing chambers or modules, metal plating chambers or modules, cleaning chambers or modules, chamfering edge etching chambers or modules, physical vapor deposition (PVD) chambers or modules, chemical vapor deposition (CVD) chambers or modules, atomic layer deposition (ALD) chambers or modules, atomic layer etching (ALE) chambers or modules, ion implantation chambers or modules, orbital chambers or modules, and any other semiconductor processing systems that may be associated with or used for the fabrication and / or preparation of semiconductor wafers.

[0143] As described above, depending on one or more processing steps to be performed by the tool, the controller may communicate with one or more other tool circuits or modules, other tool components, cluster tools, other tool interfaces, adjacent tools, neighboring tools, tools located in the plant, a host computer, another controller, or tools used in the transport of materials to and from the tool location and / or loading port in the semiconductor manufacturing plant.

Claims

1. A substrate processing system comprising: a processing chamber; a plasma source disposed to supply a plasma to the processing chamber through a gas distribution apparatus, the gas distribution apparatus configured between the processing chamber and the plasma source; first and second coils interleavedly configured on the plasma source and disposed to ignite a gas supplied to the plasma source to generate the plasma; and a power source disposed to supply power to the first and second coils in an alternating manner.

2. The substrate processing system of claim 1, wherein the power source is disposed to supply more power to the first coil than to the second coil.

3. The substrate processing system of claim 1, wherein windings of the first and second coils are interleaved with each other.

4. The substrate processing system of claim 1, wherein the first and second coils are electrically insulated from each other.

5. The substrate processing system of claim 1, further comprising a switching circuit connected to the power source, the switching circuit comprising first and second output terminals, the first output terminal connected to the first coil, the second output terminal connected to the second coil, the switching circuit disposed to supply the power from the power source to the first and second coils via the first and second output terminals, respectively, in the alternating manner.

6. The substrate processing system of claim 1, wherein the power source is disposed to supply a first radio frequency power to the first coil and a second radio frequency power to the second coil.

7. The substrate processing system of claim 6, wherein the first radio frequency power supplied to the first coil is greater than the second radio frequency power supplied to the second coil.

8. The substrate processing system of claim 6, wherein the power source is disposed to supply the first radio frequency power to the first coil for a first time period and the second radio frequency power to the second coil for a second time period.

9. The substrate processing system of claim 8, wherein the first time period is greater than the second time period.

10. The substrate processing system of claim 8, wherein the first radio frequency power supplied to the first coil for the first time period is greater than the second radio frequency power supplied to the second coil for the second time period, and wherein the first time period is greater than the second time period.

11. The substrate processing system of claim 1, wherein the power source is disposed to supply the power to the first coil to generate the plasma.

12. The substrate processing system of claim 1, wherein the power source is disposed to supply the power to the second coil to erode a material deposited on an inner surface of the plasma source in an area located between windings of the first coil.

13. The substrate processing system of claim 1, wherein the plasma source is dome-shaped, cylindrical, elliptical, or conical. ​ 14. The substrate processing system of claim 1, wherein the plasma source is dome-shaped, cylindrical, elliptical, or conical; and wherein the first coil and the second coil are configured around the plasma source.

15. The substrate processing system of claim 1, wherein the plasma source is cylindrical and has a first end coupled with the gas distribution apparatus, and wherein the first coil and the second coil are configured on a surface at a second end of the plasma source.

16. The substrate processing system of claim 1, further comprising: a syringe coupled to the plasma source, the syringe being arranged to inject a gas into the plasma source to generate the plasma; and a pedestal disposed in the processing chamber to support a substrate, wherein the gas distribution apparatus is arranged to filter out ions from the plasma and to supply radicals from the plasma into the processing chamber to process the substrate.

17. A substrate processing system, comprising: a processing chamber; a plasma source arranged to supply a plasma to the processing chamber through a gas distribution apparatus, the gas distribution apparatus being configured between the processing chamber and the plasma source; a coil configured on the plasma source and arranged to ignite a gas supplied to the plasma source to generate the plasma; and an actuator arranged to move a position of the coil on the plasma source.

18. The substrate processing system of claim 17, further comprising a power source arranged to supply power to the coil to ignite the gas, wherein the actuator is arranged to move the position of the coil while the power source supplies power to the coil.

19. The substrate processing system of claim 18, wherein the actuator is arranged to move the position of the coil to erode a material deposited on an inner surface of the plasma source in an area between windings of the coil.

20. The substrate processing system of claim 17, wherein the actuator is arranged to move the position of the coil intermittently.

21. The substrate processing system of claim 17, wherein the actuator is arranged to move the position of the coil periodically.

22. The substrate processing system of claim 17, wherein the actuator is arranged to move the position of the coil repeatedly between two positions.

23. The substrate processing system of claim 17, wherein the actuator is arranged to move the position of the coil linearly between two positions.

24. The substrate processing system of claim 17, wherein the actuator is arranged to move the position of the coil by rotating the coil to move windings of the coil over different areas of the plasma source. ​ 25. The substrate processing system of claim 17, wherein the actuator is configured to move the position of the coil by compressing and decompressing the coil.

26. The substrate processing system of claim 17, wherein the actuator is configured to move the position of the coil by periodically vibrating the coil.

27. The substrate processing system of claim 17, wherein the plasma source is dome-shaped, cylindrical, elliptical, or conical.

28. The substrate processing system of claim 17, wherein the plasma source is dome-shaped, cylindrical, elliptical, or conical; and wherein the coil is disposed around the plasma source.

29. The substrate processing system of claim 17, wherein the plasma source is cylindrical and has a first end coupled to the gas distribution apparatus, and wherein the coil is disposed on a surface at a second end of the plasma source.

30. The substrate processing system of claim 17, further comprising: a syringe coupled to the plasma source, the syringe configured to inject a gas into the plasma source to generate the plasma; and a pedestal disposed in the processing chamber to support a substrate, wherein the gas distribution apparatus is configured to filter out ions from the plasma and supply radicals from the plasma into the processing chamber to process the substrate.

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