Tunable uniformity control utilizing rotational magnetic housing

Abstract

To provide a magnetic housing system, an electromagnetic housing system, and a method for controlling the properties of plasma generated in a process volume of a process chamber to affect deposition properties of a film.SOLUTION: In one embodiment, a method includes rotation of a rotational magnetic housing about a center axis of a process volume to create dynamic magnetic fields. The magnetic fields modify the shape of a plasma, concentration of ions and radicals, and movement of concentration of ions and radicals to control the density profile of the plasma. Controlling the density profile of the plasma tunes the uniformity and properties of a deposited or etched film.SELECTED DRAWING: Figure 1A

Description

[Technical field]

[0001] SUMMARY OF THE DISCLOSURE Embodiments of the present disclosure generally relate to a rotating magnetic housing system for controlling properties of a generated plasma and methods utilizing same. [Background technology]

[0002] Cross-reference to related art Plasma enhanced chemical vapor deposition (PECVD) is commonly employed to deposit films on substrates, such as semiconductor wafers. Plasma etching is commonly employed to etch films deposited on substrates. PECVD and plasma etching are accomplished by introducing one or more gases into a process space of a process chamber containing the substrate. The one or more gases are mixed in a diffuser near the top of the chamber and introduced into the process space through multiple holes or nozzles in the diffuser. During PECVD and plasma etching, the one or more gas mixtures in the process space are energized (e.g., excited) to form a plasma by applying radio frequency (RF) energy to the chamber from one or more RF sources coupled to the chamber. An electric field is established in the process space such that atoms of the one or more gas mixtures in the process space are ionized and emit electrons. In PECVD, the ionized atoms accelerated to a substrate support facilitate deposition of a film on the substrate. In plasma etching, the ionized atoms accelerated to a substrate support facilitate etching of a film deposited on the substrate.

[0003] The plasma generated in the process space has properties such as a density profile. A non-uniform density profile can result in non-uniform deposition or etching of a film on a substrate. Specifically, the density profile of the plasma affects the deposition thickness and etch profile of a film across the substrate surface. Therefore, what is needed in the art is a method for controlling the properties of the plasma generated in the process space of a process chamber. Summary of the Invention

[0004] In an embodiment, a method is provided. The method includes placing a substrate in a chamber body of a processing system. The processing system includes a substrate support and a rotatable magnetic housing disposed within the chamber body. The substrate is disposed on the substrate support, on which an electrode is disposed. The rotatable magnetic housing is disposed outside the chamber and defines a circular central opening. A plurality of magnets are disposed in the rotatable magnetic housing. RF power is supplied to the electrode to generate a plasma in the chamber body. The rotatable magnetic housing rotates about the circular central opening such that each of the magnets moves in a circular path around the chamber body.

[0005] In another embodiment, a method is provided. The method includes disposing a substrate in a chamber body of a processing system. The processing system includes a substrate support disposed within the chamber body, an electrode disposed within the substrate support, and a rotatable magnetic housing. The substrate is disposed on the substrate support. The rotatable magnetic housing is disposed outside the chamber and defines a circular central opening. A plurality of magnets are disposed on the rotatable magnetic housing. Each of the magnets is spaced vertically from the substrate. The vertical spacing corresponds to a spacing from a plane formed through the centers of each of the magnets to the substrate. RF power is applied to the electrode to generate a plasma in the chamber body. The rotatable magnetic housing rotates about the circular central opening such that each of the magnets moves in a circular path around the chamber body. At least one of the rotatable magnetic housing or the substrate support is raised or lowered to change the vertical spacing of the magnets from the substrate.

[0006] In another embodiment, a method is provided. The method includes disposing a substrate in a chamber body of a processing system. The processing system includes a substrate support disposed within the chamber body, an electrode disposed within the substrate support, and a rotatable magnetic housing. The substrate is disposed on the substrate support. The rotatable magnetic housing is disposed outside the chamber and defines a circular central opening. A plurality of magnets are disposed on the rotatable magnetic housing. Each magnet of the plurality of magnets is removably held in a corresponding retaining bracket of the rotatable magnetic housing with a pitch between each magnet of the plurality of magnets. Each of the magnets is vertically spaced from the substrate. The vertical spacing corresponds to a spacing from a plane formed through the centers of each of the magnets to the substrate. Each of the magnets is horizontally spaced from a central axis of the chamber body. RF power is applied to the electrode to generate a plasma in the chamber body. The rotatable magnetic housing rotates about the circular central opening such that each of the magnets moves in a circular path around the chamber body. At least one of the rotation speed, pitch, vertical spacing, or horizontal spacing is adjusted.

[0007] In order that the above-mentioned features of the present disclosure may be more particularly understood, the above briefly summarized disclosure may be more particularly described by referring to embodiments, some of which are illustrated in the accompanying drawings. It should be noted, however, that the accompanying drawings depict only exemplary embodiments and therefore should not be considered as limiting the scope thereof, as other equally effective embodiments may be recognized. [Brief description of the drawings]

[0008] [Figure 1A] 1 is a schematic cross-sectional view of a plasma enhanced chemical vapor deposition (PECVD) chamber having a rotating magnetic housing system with a rotating magnetic housing disposed outside the chamber, according to an embodiment. [Figure 1B] 1 is a schematic top view of a rotating magnetic housing system according to an embodiment. [Figure 1C]1 is a schematic cross-sectional view of a PECVD chamber having an electromagnet housing system with an electromagnet housing disposed outside the chamber, according to an embodiment. [Figure 1D] 1 is a schematic top view of an electromagnet housing system according to an embodiment. [Figure 1E] 1 is a schematic cross-sectional view of a PECVD chamber having an electromagnet system according to an embodiment. [Diagram 2] 1 illustrates a flow diagram of a method for controlling a density profile of a plasma formed in a process space of a processing chamber, in accordance with an embodiment. [Figure 3A-B] 1 is a graph illustrating a density profile of a plasma in a process space, in accordance with an embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] For clarity, the same reference numbers have been used whenever possible to designate identical elements that are common to the figures. It is intended that elements and features of one embodiment may be beneficially incorporated in other embodiments without further detail.

[0010] Embodiments described herein provide magnetic housing systems, electromagnetic housing systems, and methods for controlling properties of a plasma generated in a process volume of a processing chamber that affect film deposition properties. In one embodiment, the method includes generating a dynamic magnetic field by rotating a rotating magnetic housing about a central axis of the process volume. The magnetic field modifies the plasma shape, ion and radical concentration, and ion and radical concentration trends to control the plasma density profile. Controlling the plasma density profile tunes the uniformity and properties of the deposited or etched film.

[0011] 1A, 1C, and 1E are schematic cross-sectional views of a processing system 100, such as a plasma enhanced chemical vapor deposition (PECVD) system, according to various embodiments. One example of the system 100 is the PRODUCER® system manufactured by Applied Materials, Inc., Santa Clara, Calif. It should be understood that the systems described below are exemplary chambers, and other systems, including systems from other manufacturers, may be used together or modified to achieve aspects of the present disclosure. The system 100 includes a chamber 101a (e.g., a first chamber) and a chamber 101b (e.g., a second chamber). In an embodiment, which may be combined with other embodiments described herein, the chambers 101a and 101b share resources. For example, the chambers 101a, 101b may share at least one or more gas sources 144, a mounting plate 112, and a pump 150. The chambers 101a and 101b are similarly configured. However, it is also contemplated that each of the chambers 101a, 101b may have dedicated resources.

[0012] In the embodiment of FIG. 1A, each chamber 101a, 101b has a rotatable magnetic housing system 102 having a rotatable magnetic housing 104 disposed outside the chamber 101a, 101b. In the embodiment of FIG. 1C, each chamber 101a, 101b has an electromagnet housing system 170 having an electromagnet housing 172 disposed outside the chamber 101a, 101b. In the embodiment of FIG. 1E, each chamber 101a, 101b has an electromagnet system 171 disposed on a spacer 114 of the chamber lid assembly 108. Although an embodiment of chamber 101a is described, it should be understood that chamber 101b is similarly equipped. In FIGS. 1A, 1C, and 1E, reference numbers may be omitted for chamber 101b for clarity.

[0013] The chambers 101a, 101b have a chamber body assembly 106 and a chamber lid assembly 108. The chamber body assembly 106 of the embodiment of Figures 1A and 1C includes a chamber body 110 coupled to a mounting plate 112. The chamber lid assembly 108 of the embodiment of Figures 1A and 1C includes a spacer 114 having a first flange 118 coupled to the mounting plate 112 and a chamber lid 116 coupled to a second flange 120 of the spacer 114. The chamber lid assembly 108 of the embodiment of Figure 1E includes a spacer 114 having a first flange 118 coupled to the chamber body 110 and a chamber lid 116 coupled to a second flange 120 of the spacer 114. The chamber lid 116 includes a gas distribution assembly 122. The gas distribution assembly 122 is positioned opposite a substrate support assembly 124 that defines a processing space 126 therebetween. 1A and 1C is further defined by the chamber lid 116, the inner wall 128 of the spacer 114, the mounting plate 112, and the chamber body 110. The processing space 126 of the embodiment of FIG. 1E is further defined by the chamber lid 116, the inner wall 128 of the spacer 114, and the chamber body 110.

[0014] The substrate support assembly 124 is disposed within the processing space 126. The substrate support assembly 124 includes a substrate support 130 and a stem 132. The substrate support 130 has a support surface 134 that supports a substrate 165. The substrate support 130 typically includes a heating element (not shown). The substrate support 130 is movably disposed within the processing space 126 by a stem 132 that extends through the chamber body 110, where the stem 132 is connected to a substrate support drive system 136. The substrate support drive system 136 moves the substrate support 130 between a raised processing position (as shown) and a lowered position that facilitates substrate transfer to and from the processing space 126 through a slit valve 138 formed through the chamber body 110. In an embodiment, which may be combined with other embodiments described herein, the substrate support drive system 136 rotates the stem 132 and the substrate support 130.

[0015] In one embodiment, which may be combined with other embodiments described herein, the gas distribution assembly 122 is configured to uniformly distribute gas into the processing space 126 of the chambers 101 a, 101 b to facilitate deposition of a film, such as a tip patterned film, on a substrate 165 positioned on a substrate support 130 of the substrate support assembly 124. In another embodiment, which may be combined with other embodiments described herein, the gas distribution assembly 122 is configured to uniformly distribute gas into the processing space 126 of the chambers 101 a, 101 b to facilitate etching of a film, such as a tip patterned film, on a substrate 165 positioned on a substrate support 130 of the substrate support assembly 124.

[0016] The gas distribution assembly 122 includes a gas inlet passage 140 that delivers gas from a flow controller 142 coupled to one or more gas sources 144 through a diffuser 146 suspended from a hanger plate 148. The diffuser 146 has a number of holes or nozzles (not shown) through which the gas mixture is introduced into the processing space 126 during processing. A pump 150 is coupled to an outlet 152 of the chamber body 110 to control the pressure within the processing space 126 and to evacuate by-products from the processing space 126. The diffuser 146 of the gas distribution assembly 122 can be connected to an RF return (or ground) to enable RF energy applied to the substrate support 130 to create an electric field in the processing space 126 that is used to generate a plasma during processing of the substrate 165.

[0017] The RF source 154 is coupled to an electrode 156 disposed in the substrate support 130 through a conductive rod 158 disposed through the stem 132. In an embodiment, which may be combined with other embodiments described herein, the electrode 156 is connected to the RF source 154 through a match box 163 having a match circuit for adjusting electrical characteristics, such as voltage, current, and impedance, of the electrode 156 and a sensor for measuring the electrical characteristics. The match circuit can facilitate adjustment of the voltage, current, or impedance in response to a signal from the sensor. The diffuser 146 of the gas distribution assembly 122, which is connected to the RF return, and the electrode 156 promote the formation of a capacitive plasma coupling. The RF source 154 provides RF energy to the substrate support 130 to promote the generation of a capacitively coupled plasma between the substrate support 130 and the diffuser 146 of the gas distribution assembly 122. When RF power is supplied to the electrode 156, an electric field is created between the diffuser 146 and the substrate support 130 such that gas atoms in the process space 126 between the substrate support 130 and the diffuser 146 are ionized and emit electrons. The ionized atoms accelerate into the substrate support 130 to facilitate deposition or etching of a film on a substrate 165 positioned on the substrate support 130.

[0018] 3A, the plasma has a density profile 301 in the process space 126. The density profile 301 is expressed as an ion density 302 (ions / au) at a location 304 on the horizontal plane 167 within the process space 126. 3) The density profile 301 includes a peak 303 corresponding to a maximum 305 of ion density and a width 307 corresponding to a diameter of the plasma. In an embodiment, which may be combined with other embodiments described herein, one of the rotating magnetic housing system 102, electromagnet housing system 170, and electromagnet system 171 and methods described herein control the plasma density profile 301 to tune the uniformity and properties of the deposited or etched film. One example of a property is the local stress vector of the deposited film. In some embodiments described further herein, control of the plasma density profile 301 tunes the local stress vector to result in a deposited film with a substantially uniform distribution of the stress vector. In the embodiment of FIG. 1A, the magnet rotation speed, magnet strength (Gauss), and magnet vertical position can be adjusted to facilitate corresponding adjustments in the plasma density profile. In the embodiment of FIG. 1C, the electromagnet current flow, electromagnet strength (Gauss), and electromagnet vertical position can be adjusted to facilitate corresponding adjustments in the plasma density profile. 1E embodiment, the electromagnet current flow and electromagnet strength may be adjusted to facilitate corresponding adjustments in the density profile of the plasma, for example, to one or more of the vertical position of the plasma relative to the substrate, the position of a peak in the density profile of the plasma, or the value of the ion density at a particular location relative to the substrate.

[0019] As shown in Figure 1A, a controller 164 coupled to the chambers 101a, 101b and the rotatable magnetic housing system 102 is configured to control aspects of the chambers 101a, 101b and the rotatable magnetic housing system 102 during processing. As shown in Figure 1C, a controller 164 coupled to the chambers 101a, 101b and the electromagnet housing system 170 is configured to control aspects of the chambers 101a, 101b and the electromagnet housing system 170 during processing. As shown in Figure 1E, a controller 164 coupled to the chambers 101a, 101b and the electromagnet system 171 is configured to control aspects of the chambers 101a, 101b and the electromagnet system 171 during processing.

[0020] As shown in FIG. 3A, the strength of one of the magnets 143 and the electromagnet core material (shown in FIGS. 1C and 1E) compresses the plasma density profile 301 in the process space 126 and extends the plasma sheath to the sidewall of the chamber body 110. Compressing the plasma density profile 301 leads to a more uniform concentration of ions and radicals across the substrate 165 (in relative height above the substrate) for a uniform deposition profile. Additionally, the compression of the density profile 301 extends the plasma sheath radially outward toward the sidewall of the chamber body 110. Extending the plasma sheath to the sidewall of the chamber body 110 provides a short and symmetrical path for RF energy to propagate from the sidewall to ground. The path for RF energy to propagate from the sidewall to ground improves current flow and reduces the amount of current required by the electrode 156 of the substrate support 130 due to increased efficiency. The reduced amount of current required by the electrode 156 allows more voltage to be delivered to the electrode 156 due to increased efficiency. The voltage increase results in greater ionization of the plasma sheath leading to increased ion or radical bombardment of the substrate 165. The increased ion or radical bombardment of the substrate 165 weakens the stress of the film being deposited or etched. Furthermore, the compression of the density profile 301 and the expansion of the plasma sheath results in a nearly uniform distribution of the stress vectors of the deposited or etched film.

[0021] 1B shows a schematic top view of the rotatable magnetic housing system 102. With reference to FIGS. 1A and 1B, the rotatable magnetic housing system 102 includes a rotatable magnetic housing 104 configured to rotate about a central axis 103 of the process space 126 to generate a static or dynamic magnetic field. The magnetic field modifies the plasma shape, ion and radical concentration, and ion and radical concentration trends to control the density profile 301 of the plasma in the process space 126.

[0022] A rotatable magnetic housing system 102 having a rotatable magnetic housing 104 is disposed outside the chambers 101a, 101b. The rotatable magnetic housing system 102 includes an upper plate 105, a lower plate 107 disposed opposite the upper plate 105, an inner sidewall 109, an outer sidewall 113 disposed opposite the inner sidewall 109, a housing lift system 168, and a housing drive system 115. An inner wall 128 defines a circular central opening. In an embodiment that may be combined with other embodiments described herein, at least one of the upper plate 105, the lower plate 107, or the spacer 114 has one or more channels (not shown) connected to a heat exchanger (not shown) that controls the temperature profile of the rotatable magnetic housing 104. An outer wall 162 of the spacer 114 is made of a polymeric material such as PTFE (polytetrafluoroethylene). In an embodiment that may be combined with other embodiments described herein, the outer wall 162 is a thin sheet of a polymeric material. The polymeric material of the outer wall 162 of the spacer 114 allows the rotatable magnetic housing 104 to rotate around the spacer 114 about the central axis 103 of the processing volume 126 .

[0023] The rotatable magnetic housing 104 includes a plurality of retaining brackets 129. Each retaining bracket of the plurality of retaining brackets 129 is disposed on the rotatable magnetic housing 104 with a distance d between each retaining bracket. The plurality of retaining brackets 129 allows the plurality of magnets 143 to be disposed on and removed from the rotatable magnetic housing 104. In one embodiment, each magnet 143 of the plurality of magnets 143 is held on the retaining bracket 129 with a pitch p between each magnet 143 of the plurality of magnets 143. The pitch p corresponds to the distance between adjacent magnets 143 of the plurality of magnets 143. The magnetic field generated by rotating the rotatable magnetic housing 104 is tuned by the pitch p. In one embodiment, which may be combined with other embodiments described herein, each of the retaining brackets 129 is coupled to a track 131. The retaining brackets 129 are actuated such that each of the retaining brackets 129 is operable to slide radially along the track 131 to vary the horizontal spacing 133 from each of the magnets 143 to the central axis 103 of the processing volume 126 .

[0024] As shown in FIG. 1C, an electromagnet housing system 170 having an electromagnet housing 172 is disposed outside the chambers 101a, 101b. The electromagnet housing 172 includes an upper plate 173, a lower plate 174 disposed opposite the upper plate 173, an inner sidewall 176, an outer sidewall 175 disposed opposite the inner sidewall 176, and a housing lift system 168. The inner wall 128 defines a circular central opening. In an embodiment, which may be combined with other embodiments described herein, at least one of the upper plate 173, the lower plate 174, or the spacer 114 has one or more channels (not shown) connected to a heat exchanger (not shown) that controls the temperature profile of the electromagnet housing 172. A conductive wire 178 is disposed in the electromagnet housing 172 and is coiled around the spacer 114 one or more times to form an electromagnet circumscribing the spacer 114. A power source 180 is coupled to the conductive wire 178, which carries a current in a circular path around the process space 126. In an embodiment, which may be combined with other embodiments described herein, at least one turn of the conductive wire 178 is coupled to the tracks 181. The tracks 181 are actuated such that each turn of the conductive wire 178 coupled to one of the tracks 181 is operable to slide radially along the track 181 to vary the horizontal spacing 133 from the conductive wire 178 to the central axis 103 of the process space 126. As shown in FIG. 1E, the conductive wire 178 is disposed on the spacer 114 and is coiled one or more times around the process space 126.

[0025] In one embodiment as shown in FIG. 1B, which may be combined with other embodiments described herein, the magnets 143 in the first half 137 (e.g., spanning approximately 180 degrees) of the rotatable magnetic housing 104 have their north poles 141 facing towards the process space 126, and the magnets 143 in the second half 139 (e.g., spanning approximately 180 degrees) of the rotatable magnetic housing 104 have their south poles 145 facing away from the process space 126. As shown in FIG. 3B, the first half 137 and the second half 139 with the magnets 143 facing in opposite directions results in a shift of the peak 303 of the density profile 301. The opposite polarity of the magnets 143 distorts the B field caused by the magnets 143. The distortion of the B field results in a shift of the peak 303 of the density profile 301. The shift of the peak 303 corresponds to a shift of the plasma sheath. Rotation of the rotatable magnetic housing 104 promotes more uniform exposure of the substrate 165 to the ions and radicals of the distorted plasma sheath.

[0026] The rotatable magnetic housing 104 is coupled to a housing drive system 115. The housing drive system 115 is comprised of a belt 147 and a motor 149. The rotatable magnetic housing 104 has a plurality of grooves 151 formed in an outer sidewall 113 of the rotatable magnetic housing 104. Each groove of the plurality of grooves 151 corresponds to one of a plurality of protrusions 155 of a belt 161. The belt 161 is configured to be disposed around the rotatable magnetic housing 104 and is coupled to a motor 149, such as a brushless DC electric motor. The housing drive system 115 is configured to rotate the rotatable magnetic housing 104 about a central axis 103 of the processing space 126 at a rotational speed. This rotational speed controls the current in the substrate 165 resulting from the modified magnetic field. In one example, it is contemplated that each of the chambers 101a, 101b includes a separate housing drive system 115. In another example, it is contemplated that each of the chambers 101 a , 101 b will share the housing drive system 115 .

[0027] In some embodiments of Figures 1C and 1E, which may be combined with other embodiments described herein, the conductive wire 178 has at least one air gap in the core of the conductive wire 178, the cross-sectional area of ​​the core varies, and the spacing between each turn of the conductive wire 178 varies. The core of the first half of the conductive wire 178 (e.g., spanning approximately 180 degrees) may have more air gaps than the second half of the conductive wire 178 (e.g., spanning approximately 180 degrees). The cross-sectional area of ​​the core of the first half of the conductive wire 178 may be larger than the cross-sectional area of ​​the second half of the conductive wire 178. The spacing between each turn of the conductive wire 178 in the first half may be smaller than the spacing between each turn of the conductive wire 178 in the second half. Adjusting at least one of the air gaps, cross-sectional area, or spacing between each turn of the conductive wire 178 distorts the B-field caused by the current flowing through the conductive wire 178. The current circular flow promotes more uniform exposure of the substrate 165 to the ions and radicals of the distorted plasma sheath.

[0028] In other embodiments of FIGS. 1C and 1E that may be combined with other embodiments described herein, the electromagnet housing 172 (FIG. 1C) and the electromagnet system 171 (FIG. 1E) include two or more conductive wires 178. Each of the conductive wires 178 of the electromagnet housing 172 is disposed in a respective portion of the electromagnet housing 172. Each of the conductive wires 178 of the electromagnet system 171 is disposed in a respective portion of the spacer 114. A power source 180 (180a, 180b, 180c, and 180d as shown in FIG. 1D) is separately coupled to each of the conductive wires 178. The power source 180 operable to be electrically connected to the controller 164. The controller 164 is operable to control the supply of power to each of the conductive wires 178 by turning each of the power sources 180 on and off sequentially and by turning each of the power sources 180 on and off simultaneously. Turning each of the power sources 180 off simultaneously allows for shunting of the magnetic field provided by the electromagnet. In one example, a first conductive wire is coiled one or more times in a semicircular shape and placed in a first half or spacer 114 (FIG. 1E) of the electromagnet housing 172 (FIG. 1C) that corresponds to the first half of the processing space 126 to form a first electromagnet. A second conductive wire is coiled one or more times in a semicircular shape and placed in a second half or spacer 114 (FIG. 1E) of the electromagnet housing 172 (FIG. 1C) that corresponds to the second half of the processing space 126 to form a second electromagnet. The polarity of the first electromagnet and the polarity of the second electromagnet may be reversed.

[0029] 1D, in one example, a first conductive wire 178a is coiled one or more times in a semicircle having an arc of 90 degrees or less and disposed in a first quadrant 179a of the electromagnet housing 172 corresponding to the first quadrant 126a of the processing space 126 to form a first electromagnet. A second conductive wire 178b is coiled one or more times in a semicircle having an arc of 90 degrees or less and disposed in a second quadrant 179b of the electromagnet housing 172 corresponding to the second quadrant 126b of the processing space 126 to form a second electromagnet. A third conductive wire 178c is coiled one or more times in a semicircle having an arc of 90 degrees or less and disposed in a third quadrant 179c of the electromagnet housing 172 corresponding to the third quadrant 126c of the processing space 126 to form a third electromagnet. A fourth conductive wire 178d is coiled one or more times in a semicircle having an arc of 90 degrees or less and disposed in a fourth quadrant 179d of the electromagnet housing 172 corresponding to the fourth quadrant 126d of the processing volume 126 to form a fourth electromagnet. The polarities of the first, second, third and fourth electromagnets may be alternating polarities.

[0030] The housing drive system 115 and the rotatable magnetic housing 104 are coupled to a housing lift system 168. The housing drive system 115 and the rotatable magnetic housing 104 are coupled together to facilitate vertical adjustment of the rotatable magnetic housing 104 relative to the substrate 165. The electromagnet housing 172 is coupled to the housing lift system 168 to facilitate vertical adjustment of the electromagnet housing 172 relative to the substrate 165. For example, a vertical interval 135 defined from a plane formed through the center of each of the magnets 143 to the substrate 165 can be widened or narrowed to adjust the nature of the plasma maintained in the corresponding chamber 101a or 101b. For example, a vertical interval 182 defined by a plane formed through the center of the conductive line 178 can be widened or narrowed to adjust the nature of the plasma maintained in the corresponding chamber 101a or 101b. The housing lift system 168 is operable to raise and lower the rotatable magnetic housing 104 and the housing drive system 115 simultaneously, although separate operation is also contemplated. By raising and lowering the substrate 165 by a vertical distance 135, 182, the spacing from the plasma sheath to the substrate 165 is adjusted, thereby controlling the progression of ion and radical concentrations to control properties such as uniformity and stress of the deposited or etched film. To facilitate vertical actuation, the housing lift system 168 can include one or more actuators, such as an electric motor, a stepper motor, a screwdriver with a threaded bolt, etc., that facilitate vertical actuation relative to the mounting plate 112. In one embodiment, which can be combined with other embodiments described herein, a motor 149 is coupled to the housing lift system 168 by a mount 157.

[0031] In one embodiment, which may be combined with other embodiments described herein, the thickness of the outer sidewalls 113, 117 is thickness 159. The material and thickness 159 of the outer sidewalls 113, 175 provide confinement of the magnetic field to the processing volume 126 by controlling the magnetic permeability of the outer sidewalls 113, 175. As shown in FIG. 1E, the material and thickness of the shield 184 aligned with the conductive line 178 and coupled to the outer wall 162 of the spacer 114 provide confinement of the magnetic field to the processing volume 126. The confinement of the magnetic field to the processing volume 126 reduces the effect of the magnetic field on nearby processing spaces of adjacent processing chambers, thereby enhancing processing uniformity. In one embodiment that may be combined with other embodiments described herein, as shown in Figures 1A and 1C, the chambers 101a, 101b include an actuated shield 186 operable to be raised and lowered such that an opening 190 in a body 188 of the actuated shield 186 aligns with one of the conductive lines 178 and the magnet 143. In another embodiment that may be combined with other embodiments described herein, as shown in Figure 1E, the chambers 101a, 101b include a shield 192 such that an opening 196 in a body 194 of the shield 192 aligns with the conductive lines. The material and thickness of the actuated shield 186 and the shield 192 provide confinement of the magnetic field to the process space 126.

[0032] Figure 2 is a flow diagram of a method 200 for controlling a density profile 301 of a plasma formed in a process space 126 of a processing chamber. For ease of explanation, Figure 2 will be described with reference to Figures 1A-1E. However, it should be noted that processing systems other than system 100 may be used in conjunction with method 200, and that magnetic housing assemblies other than rotatable magnetic housing system 102 may be used in conjunction with method 200.

[0033] In operation 201, a substrate 165 is placed on the support surface 134 of the substrate support 130. In one embodiment, the substrate is transferred into the chambers 101a, 101b through a slit valve 138 formed through the chamber body 110 and placed on the substrate support 130. The substrate support 130 is then raised by the substrate support actuation system 136 to an elevated processing position in the process space 126.

[0034] In operation 202, one or more gases are provided at a flow rate to the process space 126 of chambers 101a, 101b. In one embodiment, which may be combined with other embodiments described herein, a flow controller 142 delivers one or more gases from one or more gas sources 144 to a diffuser 146. One or more gas mixtures are introduced into the process space 126 through multiple holes or nozzles in the diffuser 146. In one embodiment, one or more gases are continuously provided to the diffuser 146, mixed therein, and introduced into the process space 126. In another embodiment, a pump 150 maintains the pressure in the process space; although FIG. 1A illustrates the pump 150 as being coupled to both chambers 101a, 101b, it is contemplated that each of chambers 101a, 101b may utilize a separate pump 150.

[0035] In operation 203, RF power is applied to the mixture of one or more gases. In one embodiment, an RF source 154 provides RF energy to the substrate support 130 to facilitate generation of a capacitively coupled plasma between the substrate support 130 and a diffuser 146 of the gas distribution assembly 122. RF power is supplied to the electrode 156 to create an electric field between the diffuser 146 and the substrate support 130 such that atoms of the gas in the process space 126 between the substrate support 130 and the diffuser 146 are ionized and emit electrons. The ionized atoms accelerate into the substrate support 130 to facilitate deposition or etching of a film on a substrate 165 positioned on the substrate support 130.

[0036] In operation 204, a density profile 301 of the plasma formed in the process space 126 is adjusted. In an embodiment that may be combined with other embodiments described herein, the rotatable magnetic housing 104 of the rotatable magnetic housing system 102 rotates at a rotational speed via the housing drive system 115 about the central axis 103 of the process space 126. At least one of the rotational speed, the horizontal spacing 133 from each of the magnets 143 to the central axis 103, or the vertical spacing 135 from the center of each of the magnets 143 to the substrate 165 can be adjusted during operation 204. In an embodiment that may be combined with other embodiments described herein, a current is applied to the conductive wire 178 in a circular path. The vertical spacing 135 can be adjusted by raising and lowering at least one of the rotatable magnetic housing 104 or the substrate support 130. The rotatable magnetic housing 104 generates a dynamic magnetic field. The magnetic field modifies the shape of the plasma, the ion and radical concentration, and the ion and radical concentration profile to control the plasma density profile 301, ion density 302, and diameter. Controlling the plasma density profile 301, ion density 302, and diameter tunes the uniformity and properties of the deposited film. Each magnet of the plurality of magnets 143 is held in a holding bracket with a pitch p between each magnet of the plurality of magnets 143. The pitch p corresponds to the spacing between each adjacent magnet of the plurality of magnets 143. The pitch p tunes the magnetic field generated by rotating the rotating magnetic housing 104. Adjusting the vertical spacing 135 modifies the spacing from the plasma sheath to the substrate, thereby controlling the ion and radical concentration profile, and the uniformity and properties of the deposited film, such as stress.

[0037] In some embodiments, which may be combined with other embodiments described herein, the center of each of the magnets 143 is fixed at a vertical spacing 135 from the substrate 165 prior to the generation of the plasma. In other embodiments, which may be combined with other embodiments described herein, the vertical spacing 135 varies during the generation of the plasma. The vertical spacing 135 may be static or dynamic during the generation of the plasma. In some embodiments, which may be combined with other embodiments described herein, the horizontal spacing 133 from each of the magnets 143 to the central axis 103 is fixed prior to the generation of the plasma. In other embodiments, which may be combined with other embodiments described herein, the horizontal spacing 133 varies during the generation of the plasma. The horizontal spacing 33 may be static or dynamic during the generation of the plasma.

[0038] In some embodiments, which may be combined with other embodiments described herein, the center of the conductive line 178 is fixed at a vertical distance 182 from the substrate 165 prior to plasma generation. In other embodiments, which may be combined with other embodiments described herein, the vertical distance 182 varies during plasma generation. The vertical distance 182 may be static or dynamic during plasma generation. The vertical distance 182 may be adjusted by raising or lowering at least one of the electromagnet housing 172 or the substrate support 130. The electromagnet housing 172 produces a dynamic magnetic field. This magnetic field modifies the shape of the plasma, the concentration of ions and radicals, and the motion of ions and radicals, controlling the density profile 301, ion density 302, and diameter of the plasma. Controlling the density profile 301, ion density 302, and diameter of the plasma tunes the uniformity and properties of the deposited film. Adjusting the vertical distance 182 modifies the spacing of the plasma sheath to the substrate, thereby controlling the motion of ions and radicals to control the uniformity and properties of the deposited film, such as stress. In some embodiments, which may be combined with other embodiments described herein, the horizontal spacing 133 from the conductive lines 178 to the central axis 103 is fixed prior to the generation of the plasma. In other embodiments, which may be combined with other embodiments described herein, the horizontal spacing 133 varies during the generation of the plasma. The horizontal spacing 133 may be static or dynamic during the generation of the plasma.

[0039] In another embodiment that may be combined with other embodiments described herein, the orientation of the magnets 143 in the first half 137 of the rotatable magnetic housing 104 is reversed from the orientation of the magnets 143 in the second half 139 of the rotatable magnetic housing 104 in operation 204. In an embodiment that may be combined with other embodiments described herein, adjustment of at least one of the air gap, cross-sectional area, or spacing between each turn of the conductive wire 178 may be adjusted in operation 204. In another embodiment that may be combined with other embodiments described herein, power is applied in sequence to two or more electromagnets of opposing or alternating polarity in operation 204.

[0040] In some embodiments, the substrate support drive system 136 rotates the substrate support 130 about the central axis 103 of the processing space 126 at a rotational speed. The strength of the magnets 143 is selected to position the peak of the plasma profile at a desired radial location on the surface of the substrate to be processed. In embodiments including magnets 143 with opposing orientations, the B field produced by the magnets 143 is distorted. In embodiments including adjusting at least one of the gap, cross-sectional area, or spacing between each turn of the conductive wire 178, the B field produced by the current flow through the conductive wire 178 is distorted. In embodiments including sequentially powering two or more electromagnets with opposing or alternating polarities, the B field produced by the current flow through the conductive wire 178 is distorted. The distortion of the B field shifts the peak of the plasma sheath. However, during processing, the rotation of the magnets 143 and the current flow through the conductive wire 178 in a circular path around the processing space 126 promotes more uniform exposure of the substrate to the ions and radicals of the distorted plasma sheath. In other embodiments, the substrate is rotated, resulting in a uniform deposition profile, whereas conventional processes utilize a plasma profile that peaks in the center on the substrate. Such a configuration results in non-uniform deposition (e.g., dense center deposition) even as the substrate is rotated, due to an increased ion density at the center of the substrate relative to the radially outer edge of the substrate.

[0041] It is contemplated that aspects of the present disclosure may be utilized with permanent magnets, electromagnets, or a combination thereof. It is further contemplated that the magnets may be arranged in alternating polarity configurations, and that magnets of like polarity may be arranged in groups, such as groups spanning approximately 180 degrees.

[0042] In summary, magnetic and electromagnetic systems and methods are described herein for controlling the density profile of a plasma formed in a process space of a process chamber. In one embodiment, the method includes generating a static or dynamic magnetic field by rotation of a rotatable magnetic housing about a central axis of the process space. The magnetic field modifies the plasma shape, ion and radical concentration, and ion and radical concentration trends to control the density profile of the plasma. Controlling the density profile of the plasma tunes the uniformity and properties of the deposited or etched film.

[0043] What has been described above is directed to examples of the present disclosure; however, other and further examples of the present disclosure may be devised without departing from the basic scope of the disclosure, which is defined by the claims that follow.

Claims

1. disposing a substrate on a substrate support disposed within a chamber body of a processing system; applying RF power to an electrode disposed within the substrate support to generate a plasma within the chamber body; rotating a rotatable magnetic housing of the processing system around an exterior of the chamber body such that magnets of the rotatable magnetic housing move in a circular path around the chamber body; and raising or lowering the rotatable magnetic housing to adjust a vertical spacing corresponding to a spacing from a plane formed through the centers of each of the magnets to the substrate.

2. The method of claim 1 , wherein the rotating magnetic housing rotates at a rotational speed.

3. 3. The method of claim 2, wherein each magnet of the plurality of magnets is removably held within a corresponding retaining bracket of the rotatable magnetic housing with a pitch between each magnet of the plurality of magnets.

4. The method of claim 3 , wherein each of the magnets is spaced horizontally from a central axis of the chamber body.

5. The method of claim 4 , further comprising adjusting at least one of the rotational speed, the pitch, the vertical spacing, or the horizontal spacing.

6. The method of claim 5 , further comprising raising or lowering the substrate support to vary the vertical spacing of the magnet from the substrate.

7. The method of claim 6 , wherein a housing lift system coupled to the rotatable magnetic housing raises and lowers the rotatable magnetic housing.

8. The method of claim 3 , wherein the restrainer bracket is coupled to a track, and the restrainer bracket is actuated to move on the track.

9. The method of claim 1 , wherein one or more gases are supplied to the processing volume of the chamber body.

10. The method of claim 9 , wherein the one or more gases are supplied to the processing space through a diffuser, and a capacitively coupled plasma is generated between the substrate support and the diffuser.

11. 2. The method of claim 1, wherein the magnets in a first half of the rotatable magnetic housing have a positive pole facing toward a central opening of the rotatable magnetic housing and the magnets in a second half of the rotatable magnetic housing have a negative pole facing away from the central opening.

12. The rotating magnetic housing is coupled to a drive system, the drive system comprising:

2. The method of claim 1, further comprising a motor coupled to a belt, the belt being adapted to be disposed around the rotatable magnetic housing, the belt having a plurality of protrusions, each protrusion corresponding to one of a plurality of grooves in an outer sidewall of the rotatable magnetic housing.

13. placing a substrate on a substrate support within a chamber body of a processing system; applying RF power to an electrode disposed within the substrate support to generate a plasma in the chamber body; rotating a rotatable magnetic housing of the processing system around an exterior of the chamber body such that magnets of the rotatable magnetic housing move in a circular path around the chamber body; raising or lowering the rotatable magnetic housing and raising or lowering the substrate support to vary a vertical spacing corresponding to a spacing of the substrate from a plane formed through the centers of each of the magnets.

14. 14. The method of claim 13, further comprising adjusting at least one of a rotational speed of the rotatable magnetic housing, a pitch between each magnet of the plurality of magnets, the vertical spacing, or a horizontal spacing of the plurality of magnets to a central axis of the chamber body.

15. 15. The method of claim 14, wherein each magnet of the plurality of magnets is removably held within a corresponding retaining bracket of the rotatable magnetic housing with the pitch spaced between each magnet of the plurality of magnets.

16. The method of claim 15 , wherein the restrainer bracket is coupled to a track, and the restrainer bracket is actuated to move on the track.

17. The method of claim 13 , wherein a housing lift system coupled to the rotatable magnetic housing raises and lowers the rotatable magnetic housing.

18. 14. The method of claim 13, wherein the magnets in a first half of the rotatable magnetic housing have a positive pole facing toward a central opening of the rotatable magnetic housing and the magnets in a second half of the rotatable magnetic housing have a negative pole facing away from the central opening.

19. disposing a substrate on a substrate support disposed within a chamber body of a processing system; applying RF power to an electrode disposed within the substrate support to generate a plasma within the chamber body; rotating a rotatable magnetic housing of the processing system at a rotational speed around an exterior of the chamber body such that a plurality of magnets of the rotatable magnetic housing move in a circular path around the chamber body; raising or lowering the rotatable magnetic housing to adjust a vertical spacing corresponding to a spacing from a plane formed through the centers of each of the magnets to the substrate; The rotation speed, the pitch between each magnet of the plurality of magnets removably retained within corresponding retaining brackets of the rotatable magnetic housing; or a horizontal spacing of the plurality of magnets from a central axis of the chamber body; and adjusting at least one of:

20. The method of claim 14 , wherein one or more gases are supplied to the processing volume of the chamber body.

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