Method and apparatus for toroidal plasma generation

Abstract

Methods and apparatus for forming a plasma in a processing chamber use a ring exciter formed of a first conductive material, the ring exciter having a first end electrically connected to an RF power source providing an RF current and a second end connected to ground; and an annular applicator physically separated from the annular exciter, the annular applicator being formed of a second conductive material having at least one fillet seam having an angle forming an upper overlapping portion and a lower overlapping portion separated by a high-K dielectric material, the high-K dielectric material is configured to provide capacitance along with the inductance of the annular applicator to form a resonant circuit that is configured to resonate when the annular exciter flows an RF current that inductively excites the annular applicator to a resonant frequency that forms an azimuthal plasma from the annular applicator.

Description

Technical Field

[0001] Embodiments of the present principles generally relate to semiconductor chambers used in semiconductor processing. Background Art

[0002] During deposition and etching in a process chamber, unwanted materials may accumulate on the interior of the process chamber. Sometimes the accumulation is caused by actual sputtering deposits, while other materials may be the result of the chemistry used during processing. The unwanted deposits may alter the desired performance of the deposition or etching process. The inventors have observed that if the process chamber could be cleaned and maintained without disassembling the process chamber or replacing expensive process kit components, throughput could be increased and costs reduced. The inventors have also observed that better control over deposition thickness would also result in higher performance structures formed on the substrate.

[0003] Thus, the inventors have provided improved methods and apparatus to generate azimuthal plasma sources that can be used for cleaning and also to affect deposition thickness and etch processes. Summary of the invention

[0004] Methods and apparatus are provided herein for wirelessly generating an azimuthal plasma in a processing chamber.

[0005] In some embodiments, an apparatus for forming a plasma in a processing chamber may include a toroidal energizer formed of a first conductive material, the toroidal energizer having a first end electrically connected to an RF power source providing an RF current and a second end connected to ground; and a toroidal applicator physically separated from the toroidal energizer, the toroidal applicator formed of a second conductive material, the second conductive material having at least one angular slot having an angle forming an upper overlap portion and a lower overlap portion separated by a high-K dielectric material, the high-K dielectric material being configured to provide capacitance together with an inductance of the toroidal applicator to form a resonant circuit, the resonant circuit being configured to resonate when the toroidal energizer flows an RF current, the RF current inductively exciting the toroidal applicator to a resonant frequency, the resonant frequency forming an azimuthal plasma from the toroidal applicator.

[0006] In some embodiments, the apparatus may further include wherein the angle is about 1 degree to about 4 degrees, wherein the high-K dielectric material has a thickness of about 1 micron or greater, the thickness separating at least one corner gap by about 1 micron or greater, wherein the RF power source provides a power of greater than zero to about 5 kW to the ring energizer, wherein the ring energizer is positioned below the ring applicator, wherein the first conductive material and the second conductive material are aluminum, wherein the high-K dielectric material is coated onto at least a portion of the ring applicator, wherein the high-K dielectric material is an insulator positioned between an upper overlap portion and a lower overlap portion, wherein the ring energizer and the ring applicator are embedded in a ceramic material, wherein the ring energizer and the ring applicator are positioned in a baffle of a substrate support surrounding a processing chamber, and / or wherein the apparatus has a plurality of ring energizers or a plurality of ring applicators.

[0007] In some embodiments, a method of forming a plasma in a processing chamber may include: exciting a ring energizer with an RF power source, wherein the ring energizer is formed of a first conductive material, the ring energizer having a first end electrically connected to the RF power source to provide an RF current and a second end connected to ground; and inductively coupling the ring energizer to a ring applicator to generate an azimuthal plasma from the ring applicator, wherein the ring applicator is physically separated from the ring energizer and the ring applicator is formed of a second conductive material, the second conductive material having at least one angular gap, the at least one angular gap having an angle forming an upper overlapping portion and a lower overlapping portion separated by a high-K dielectric material, the high-K dielectric material being configured to provide a capacitance together with an inductance of the ring applicator to form a resonant circuit, the resonant circuit being configured to resonate at a resonant frequency when the ring energizer is inductively coupled to the ring applicator.

[0008] In some embodiments, the method may further include cleaning a surface of the processing chamber by energizing the ring energizer and energizing a resonant frequency within the ring applicator to form a plasma to remove deposits from the surface, changing a deposition thickness of a deposition material on a substrate by energizing the ring energizer and energizing a resonant frequency within the ring applicator to form a plasma, changing a deposition thickness of a deposition material on an edge of a substrate by energizing the ring energizer and energizing a resonant frequency within the ring applicator to form a plasma, wherein the ring energizer and the ring applicator surround a substrate support of the processing chamber, adjusting the azimuthal plasma by adjusting an amount of overlap of an upper overlap portion and a lower overlap portion, by adjusting a width of the ring applicator, by adjusting a thickness of a high-K dielectric material between the upper overlap portion and the lower overlap portion, or by adjusting an amount of RF power applied to the ring energizer, wherein the ring energizer and the ring applicator are embedded in a ceramic material of a baffle surrounding a substrate support in the processing chamber, and / or adjusting an angle to change the resonant frequency of the ring applicator based on the frequency of the RF power applied to the ring energizer.

[0009] In some embodiments, a non-transitory computer readable medium has instructions stored thereon that, when executed, cause a method of forming a plasma in a processing chamber to be performed, the method may include the steps of: exciting a ring driver with an RF power source, wherein the ring driver is formed of a first conductive material, the ring driver having a first end electrically connected to the RF power source to provide an RF current and a second end connected to ground; and inductively coupling the ring driver to a ring applicator to generate an azimuthal plasma from the ring applicator, wherein the ring applicator is physically separated from the ring driver, and the ring applicator is formed of a second conductive material, the second conductive material having at least one angular gap, the at least one angular gap having an angle forming an upper overlapping portion and a lower overlapping portion separated by a high-K dielectric material, the high-K dielectric material being configured to provide a capacitance together with an inductance of the ring applicator to form a resonant circuit, the resonant circuit being configured to resonate at a resonant frequency when the ring driver is inductively coupled to the ring applicator.

[0010] In some embodiments, the non-transitory computer readable medium may further include a method comprising the steps of: changing the deposition thickness of the deposition material on the edge of the substrate by energizing a ring energizer and exciting a resonant frequency within a ring applicator to form a plasma, wherein the ring energizer and the ring applicator surround a substrate support of a processing chamber, adjusting the azimuthal plasma by adjusting the amount of overlap of the upper overlap portion and the lower overlap portion, by adjusting the width of the ring applicator, by adjusting the thickness of the high-K dielectric material between the upper overlap portion and the lower overlap portion, or by adjusting the amount of RF power applied to the ring energizer, and / or adjusting the angle to change the resonant frequency of the ring applicator based on the frequency of the RF power applied to the ring energizer.

[0011] Other and further embodiments are disclosed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Embodiments of the present principles, briefly summarized above and discussed in more detail below, can be understood by referring to the illustrative embodiments of the principles depicted in the accompanying drawings. However, the accompanying drawings depict only typical embodiments of the present principles and are therefore not to be considered limiting of the scope, as the present principles may admit to other equally effective embodiments.

[0013] Figure 1 Depicted are schematic cross-sectional views of processing chambers, according to some embodiments of the present principles.

[0014] Figure 2 Depicted are schematic cross-sectional views of baffles, according to some embodiments of the present principles.

[0015] Figure 3 Depicted is an isometric view of a ring exciter, according to some embodiments of the present principles.

[0016] Figure 4 Depicted is a top view of a ring applicator, according to some embodiments of the present principles.

[0017] Figure 5 Depicted is a partial side view of a ring applicator, according to some embodiments of the present principles.

[0018] Figure 6 Depicted is a partial side view of a ring applicator with reduced overlap, according to some embodiments of the present principles.

[0019] Figure 7 Depicted is a partial side view of a ring applicator with a dielectric coating, according to some embodiments of the present principles.

[0020] Figure 8 Depicted is a cross-sectional view of a ring applicator, according to some embodiments of the present principles.

[0021] Fig. 9 Depicted is a cross-sectional view of a processing chamber having an annular applicator that generates an annular plasma to clean the processing chamber, according to some embodiments of the present principles.

[0022] Fig.10 Depicted are cross-sectional views of a processing chamber having an annular applicator that increases or decreases ion density near the edge of a substrate, according to some embodiments of the present principles.

[0023] Fig.11 Depicted is a cross-sectional view of a processing chamber having an annular applicator that affects a sheath of a localized plasma in a processing volume, according to some embodiments of the present principles.

[0024] Fig.12 Depicted are cross-sectional views of a processing chamber with different positions of one or more ring applicators, according to some embodiments of the present principles.

[0025] Fig.13 A method of wirelessly forming a plasma in a processing chamber in accordance with some embodiments of the present principles.

[0026] For ease of understanding, the same reference numerals have been used, where possible, to represent the same elements common to the figures. These figures are not drawn to scale and may be simplified for clarity. Elements and features of one embodiment may be beneficially incorporated into other embodiments without further description. DETAILED DESCRIPTION

[0027] Methods and apparatus provide for wireless generation of azimuthal plasma in a processing chamber. In some embodiments, by wirelessly transmitting RF power to a resonant ring applicator with the aid of a ring exciter, an inductive plasma can be local to the edge of a chip. As the ring applicator forms a circle, the ring applicator eliminates the use of discrete lumped capacitors and creates an equivalent capacitance by overlapping metal portions. The diameter of the resulting metal ring of the ring applicator forms an equivalent inductor that resonates with the equivalent capacitance. The methods and apparatus can be used to generate a plasma around a wafer, which can be used to clean polymer deposits in baffle areas, etc., to adjust a local processing volume plasma sheath at the edge of the wafer, and / or to generate effective free radicals and density at the edge of the wafer.

[0028] The present principle has the advantage of providing a locally generated inductively coupled plasma near the edge of the wafer in the form of an azimuthal annular plasma. The annular applicator can be a single one-turn thin (low profile) resonant plasma applicator without a power cord, thereby allowing optimal placement and modification without the need to power the annular applicator. The annular applicator also has the advantage of providing a resonant structure, which is excited by the azimuthal electric field generated by the oscillating axial magnetic field induction from the annular exciter. When excited at a resonant frequency, the annular applicator will experience current amplification due to the resonance generated by the oscillating axial magnetic field (B field), which in turn generates an azimuthal plasma around the annular applicator. The generation of local inductive plasma is very effective for cleaning polymers that are difficult to obtain in the wafer interface of the processing kit and for adjusting the sheath of the processing volume plasma. In addition, the overlap, overlap spacing distance, and / or width of the annular applicator can be varied to generate effective capacitances of different values. The diameter of the annular applicator can also be varied to generate different effective inductance values, thereby allowing the annular applicator to resonate at a desired frequency for a given RF power source. The annular applicator and the annular exciter can also be embedded in a ceramic support surface of a ceramic baffle or substrate support, etc. to simplify installation.

[0029] The exciter circuit provided by the ring exciter can be a single turn or multi-turn inductive loop or an element capacitively coupled from the exciter to the applicator. The resonant applicator forms an equivalent capacitance by overlapping portions of discrete metal structures formed by angular segmentation from the top surface of the ring applicator through the ring applicator to the bottom surface of the ring applicator to form an upper overlapping portion and a lower overlapping portion while the ring applicator still forms a ring or ring structure when viewed from a top view (see, e.g. Figure 4 ). For example, the resonant frequency can be customized by adjusting the diameter of the ring applicator (equivalent inductance value) and / or the overlap amount of the upper overlapping portion and the lower overlapping portion of the ring applicator (equivalent capacitance value).

[0030] The methods and apparatus can be used in different types of processing chambers, such as deposition chambers or etching chambers. In some embodiments, the processing chamber can be treated with chemicals and / or treated with local plasma and / or remote plasma. As an example chamber is used and is not meant to be limiting, Figure 1 A cross-sectional view of a processing chamber 100 with a remote plasma source 164 is depicted in accordance with some embodiments. The processing chamber 100 is a vacuum chamber that maintains a sub-atmospheric pressure within an interior volume 102 during substrate processing. In some embodiments, the processing chamber 100 can maintain a pressure of about 1 mTorr to 100 Torr. The processing chamber 100 includes a chamber body 106 that surrounds a processing volume 108 located in an upper half of the interior volume 102. The chamber body 104 can be made of a metal, such as aluminum, etc. The chamber body 104 can be grounded by coupling to a ground line 110.

[0031] The substrate support 112 is disposed within the interior volume 102 to support and hold a substrate 114, such as a semiconductor wafer, or other such substrate. The substrate support 112 may generally include a base 116 and a hollow support shaft 118 for supporting the base 116. The base 116 may be formed of an aluminum-based material or a ceramic-based material, among others. A base formed of a ceramic-based material may be used for high temperature processing. The hollow support shaft 118 provides a conduit to provide, for example, backside gas, process gas, fluid, coolant, power, etc. to the base 116. In some embodiments, the substrate support 112 includes a baffle 120 disposed around the base 116. In some embodiments, the baffle 120 is made of a ceramic-based material. Ceramic-based materials facilitate high pressure processing capabilities. In some embodiments, the baffle 120 may include a ring exciter and a ring applicator discussed in detail below (see, e.g., Figure 2 ). The ring exciter in the baffle 120 can be in electrical contact with an RF exciter power source 192 via a matching network 190A, and can also be in electrical contact with a ring exciter ground 196. The RF exciter power source 192 can provide up to about 5 kW of power. A slit valve 122 can be coupled to the chamber body 104 to facilitate transferring the substrate 114 into and out of the interior volume 102.

[0032] In some embodiments, the hollow support shaft 118 is coupled to a lift actuator 124, such as a motor, which provides vertical movement of the base 116 between an upper processing position and a lower transfer position. The substrate elevator 126 may include a lift pin 128 mounted on a platform 130 connected to a shaft 132, which is coupled to a second lift actuator 134 for raising and lowering the substrate elevator 126 so that the substrate 114 can be placed on or removed from the base 116. The base 116 may include a through hole to receive the lift pin 128. The hollow support shaft 118 provides a path for a gas conduit 194 for coupling a backside gas supply 136 and / or an RF power supply 138 to the base 116. In some embodiments, the RF power supply 138 provides bias power to the power conduit 142 through a matching network 140 to the base 116. In some embodiments, the RF energy provided by the RF power supply 138 may have a frequency of about 2 MHz or higher. In some embodiments, the RF power supply 138 may have a frequency of about 13.56 MHz.

[0033] In some embodiments, a backside gas supply 136 is disposed outside of the chamber body 104 and supplies gas to the base 116. In some embodiments, the base 116 includes a gas channel 144 that allows the gas to interact with the back side of the substrate 114 to maintain a given temperature. The gas channel 144 is configured to provide a backside gas such as nitrogen (N), argon (Ar), or helium (He) to the upper surface 146 of the base 116 as a heat transfer medium. The gas channel 144 is in fluid communication with the backside gas supply 136 via a gas conduit 194 to control the temperature and / or temperature distribution of the substrate 114 during use. For example, the backside gas supply 136 can supply gas to cool and / or heat the substrate 114 during use. In some embodiments, the substrate 114 can be heated from about 60 degrees Celsius to about 450 degrees Celsius.

[0034] The processing chamber 100 includes a process kit surrounding various chamber components to prevent undesirable reactions between these components and contaminants. The process kit includes an upper shield 148. In some embodiments, the upper shield 148 can be made of a metal (e.g., aluminum). In some embodiments, the process kit can be composed of quartz. In some embodiments, a mixing reservoir 156 is coupled to the processing volume 108 and is in fluid communication with the processing volume 108. The mixing reservoir 156 is also fluidly connected to the RPS 164. The mixing reservoir 156 allows the plasma gas to mix with other gases provided by the gas delivery system 150. The flow rate of the other gases from the gas delivery system 150 can be controlled by a first flow valve 188.

[0035] The showerhead 158 is located above the processing volume 108 and below the ceiling 162 of the chamber body 104. The showerhead 158 includes a through hole 160 to allow gas to flow from the mixing reservoir 156 into the processing volume 108. The RPS 164 is fluidly connected to the mixing reservoir 156 to allow ionized gas to flow from the RPS 164 into the mixing reservoir 156, through the showerhead 158, and into the processing space 108. Plasma is generated in the RPS 164 by a plasma RF power supply 166 that provides RF energy to the RPS 164. The process gas used to form the plasma is supplied by the process gas source 170 and controlled by the second flow valve 186. The plasma gas supplied by the process gas source 170 may include, but is not limited to, hydrogen, helium, and / or argon, etc. The RPS 164 generates ions and radicals of the process gas to facilitate processing the substrate 114.

[0036] The pump port 172 is configured to facilitate the removal of particles and gases from the interior volume 102. The processing chamber 100 is coupled to and in fluid communication with a vacuum system 174, which includes a throttle valve (not shown) and a pump (not shown) for exhausting the processing chamber 100. In some embodiments, the vacuum system 174 is coupled to the pump port 172 disposed on the bottom surface 176 of the chamber body 104. The pressure within the processing chamber 100 can be adjusted by adjusting the throttle valve and / or the vacuum pump. In some embodiments, the pump has a flow rate of about 1900 liters per second to about 3000 liters per second. In some embodiments, the vacuum system 174 can be used to facilitate adjusting the substrate temperature.

[0037] In some embodiments, a controller 178 is used for the operation of the process chamber 100. The controller 178 may use direct control of the process chamber 100, or alternatively, use indirect control of the process chamber 100 by controlling a computer (or controller) associated with the process chamber 100. In operation, the controller 178 enables data collection and feedback from the process chamber 100 to optimize the performance of the process chamber 100. The controller 178 generally includes a central processing unit (CPU) 180, a memory 182, and support circuits 184. The CPU 180 may be any form of general-purpose computer processor that may be used in an industrial setting. The support circuits 184 are conventionally coupled to the CPU 180 and may include caches, clock circuits, input / output subsystems, power supplies, etc. A software program (such as the method described below) may be stored in the memory 182 and, when executed by the CPU 180, transforms the CPU 180 into a special-purpose computer (controller 178). The software program may also be stored and / or executed by a second controller (not shown) located remotely from the process chamber 100. The controller 178 may be used to adjust the RF power and / or frequency to the ring exciter (discussed below) to adjust the plasma formation around the ring applicator (discussed below).

[0038] The memory 182 is in the form of a computer-readable storage medium that contains instructions that, when executed by the CPU 180, facilitate the operation of the semiconductor processing and device. The instructions in the memory 182 are in the form of a program product, such as a program that implements the method of the present principles. The program code may conform to any of a variety of different programming languages. In one example, the present disclosure may be implemented as a program product stored on a computer-readable storage medium for use with a computer system. The program of the program product defines the functions of various aspects (including the methods described herein). Exemplary computer-readable storage media include, but are not limited to: non-writable storage media (e.g., read-only memory devices within a computer, such as CD-ROM disks readable by a CD-ROM drive, flash memory, ROM chips, or any type of solid-state non-volatile semiconductor memory), information is permanently stored on non-writable storage media; and writable storage media (e.g., floppy disks in disk drives or hard drives or any type of solid-state random access semiconductor memory), changeable information is stored on writable storage media. Such computer-readable storage media are aspects of the present principles when carrying computer-readable instructions that direct the functions of the methods described herein.

[0039] Figure 2 A cross-sectional view 200 of the baffle 120 is depicted in accordance with some embodiments. The ring exciter 204 is embedded in an insulating material 208 of the baffle 120, such as, but not limited to, a ceramic material (e.g., alumina). The ring exciter 204 has a first end 304 connected to the RF exciter power supply 192 via the matching network 190 and a second end 306 connected to the exciter ground 194, as shown in FIG. Figure 3 In some embodiments, the ring exciter 204 may include multiple turns (not shown) or a single turn, such as Figure 3 The current 308 oscillates in the ring energizer 204 and generates an oscillating axial B-field 310, which in turn wirelessly supplies power to form an azimuthal plasma around the ring applicator 202 when the ring energizer 204 and the ring applicator 202 are physically separated. The RF energizer power supply 192 can provide up to 5 kW of power to the ring energizer 204. In some embodiments, the ring energizer 204 can be positioned below the ring applicator 202, such as Figure 2 As shown, it is either concentrically positioned within the ring applicator 202 or concentrically surrounding the outside of the ring applicator 202 ( Figure 2 In some embodiments, the ring activator 204 may be positioned above the ring applicator 202 ( Figure 2 not shown).

[0040] The ring applicator 202 has a Figure 4The ring shape shown in the top view 400 of the ring applicator 202. When calculating the equivalent inductance value formed by the ring applicator 202, the midpoint circle 402 (the middle position between the inner diameter 408 and the outer diameter 410 of the ring applicator) can be used to determine the diameter 404 of the ring applicator 202 and the cross-sectional area of ​​the ring applicator 202. At least one corner slit 406 (see, for example Figure 5 ) may be formed through the ring applicator 202 to produce an equivalent capacitance in the ring applicator 202. The amount of equivalent capacitance and equivalent inductance provided by the ring applicator 202 determines the resonant frequency of the ring applicator 202 (fr = 1 / (2xπx√(LxC))). Adjusting the equivalent inductance and / or capacitance allows for different resonant frequencies. Figure 5 As shown in the cross-sectional view 500 of , the equivalent capacitor is formed by at least one corner slot 406 having an overlapping corner 504 passing through the ring applicator 202 to form a top overlapping portion 508 and a bottom overlapping portion 510.

[0041] A high-K dielectric material 502 is formed between the top overlap portion 508 and the bottom overlap portion 510, having a dielectric thickness 512. As used herein, the term "high-K dielectric material" refers to a dielectric material having a high dielectric constant (K, Kappa) compared to silicon dioxide (e.g., in some embodiments, K is greater than 3.9. In some embodiments, K is greater than 7). In some embodiments, the dielectric thickness 512 may be about 1 micron or greater. The overlap area 506 determines the amount of equivalent capacitance formed by the ring applicator 202. In some embodiments, more than one angle gap may be formed in the ring applicator 202 to increase the equivalent capacitance without requiring an additional conventional type capacitor bank. The overlap angle 504 may also be used as an adjustment knob to adjust the resonant frequency of the ring applicator 202. For example, a very high electric field at a desired frequency may be achieved by adjusting the overlap angle 504 for a given processing chamber design. The resonant characteristics of the ring applicator 202 amplify the current induced by the ring exciter 204 to provide a high azimuthal electric field for generating a plasma. Unlike conventional discrete capacitors, the equivalent capacitive elements of the ring applicator 202 (angular slots separated by dielectric material) are capable of operating at high current levels.

[0042] exist Figure 6 In the cross-sectional view 600 of FIG. 5 , the length of the top end 602 of the top overlapping portion 508 has been reduced, and the length of the bottom end 604 of the bottom overlapping portion has been reduced to reduce the overlapping area 506 to a reduced overlapping area 606. Figure 7In the cross-sectional view 700 of FIG. 2 , the high-K dielectric material 502 is formed by applying the coating 702 to the bottom overlap portion 510 or more of the ring applicator 202. In some embodiments, the coating 702 may also be applied to the top overlap portion 508 or more of the ring applicator 202 alone or in combination with the coating on the bottom overlap portion 510. The equivalent capacitance of the ring applicator 202 may be adjusted by the amount of overlap area 506, the width 802 of the ring applicator 202, and the dielectric thickness 512, as shown in FIG. Figure 8 (as well as Figure 5-Figure 7 ) is shown in a cross-sectional view 800 of FIG. 2. When the ring applicator 202 is excited by the oscillating B field generated by the ring energizer 204, an azimuthal electric field 804 is formed around the ring applicator 202, which generates an azimuthal ring plasma along the ring applicator 202. The resulting electric field of the ring applicator 202 is generated by the induced current, which is amplified when the ring applicator 202 is operated at a resonant frequency. The amount of applied power provided to the ring energizer 204 can also be used to adjust the plasma generated by the ring applicator 202.

[0043] exist Fig. 9 In the cross-sectional view 900 of the chamber body 104, the baffle 120 is configured with a toroidal energizer 204 that energizes the toroidal applicator 202 to form an azimuthal toroidal plasma 904 along the toroidal applicator to clean deposits 902 (e.g., polymer or other process deposits, etc.) from the substrate support 112. The radius 906 of the azimuthal toroidal plasma 904 can be adjusted by varying the amount of RF power applied to the toroidal energizer 204 to more or less clean the surrounding surfaces. Fig.10 In the cross-sectional view 1000A of the chamber body 104, the baffle 120 is configured with a ring energizer 204, which energizes the ring applicator 202 to form an electric field to generate plasma, thereby increasing the ion density 1002A at the edge 1004 of the substrate 114. Similarly, as Fig.10 As shown in the cross-sectional view 1000B of FIG. 1000B, the electric field and the subsequently generated plasma can be reduced to reduce the ion density 1002B at the edge 1004 of the substrate 114. The ring applicator 202 can also be used to influence the sheath 1110 of the local plasma 1112 in the processing chamber 1104, such as Fig.11 1100. The sheath 1110 can be affected, for example, to a first position 1102 to increase edge deposition or etching of the substrate 114, or to a second position 1104 to reduce edge deposition or etching of the substrate 114.

[0044] The method and apparatus of the present principles may also be used to adjust other processing parameters, etc. Thus, pairs of ring applicators and ring energizers may be positioned at different locations within a processing chamber and may also be used in conjunction with other pairs within the same processing chamber, such as Fig.12 1200. For example, a first annular applicator / initiator pair 1202 is positioned near the top of the processing volume 1220. A second annular applicator / initiator pair 1204 is positioned near the middle of the processing volume 1220. A third annular applicator / initiator pair 1206 is embedded in the substrate support 112 near the edge of the substrate 114, and a fourth annular applicator / initiator pair 1208 is embedded inwardly into the third annular applicator / initiator pair 1206. In some embodiments, the first annular applicator / initiator pair 1202 and the second annular applicator / initiator pair 1204 can be used to influence the directionality of ions, etc. or even serve as the primary plasma source within the processing volume 1220. In some embodiments, the third annular applicator / initiator pair 1206 and the fourth annular applicator / initiator pair 1208 can be used to influence the directionality of ions onto portions of the substrate 114 other than the edge region, as described above with respect to the annular applicator / initiator pairs embedded in the baffle 120. The ease and flexibility of installation is particularly useful in process chambers with metal bodies and lids that are not conducive to the use of external induction coils to generate plasma, such as to clean the interior surfaces of the process chamber. Fig.12 , but the ring applicator / activator pair can be mounted separately rather than embedded in a ceramic material to form a single unit for installation. In some embodiments, the ring applicator and ring activator are positioned within approximately one centimeter or less of each other to achieve optimal energy transfer from the ring activator to the ring applicator. In some embodiments, the plane of the ring applicator can be tilted relative to the plane of the ring activator to allow for easier installation, especially in retrofit situations. As long as the tilt angle between the planes is less than 90 degrees, energy transfer will still occur, although at a lower efficiency.

[0045] exist Fig.13, a method 1300 of forming a plasma in a processing chamber is depicted. In block 1302, a ring exciter is excited using an RF power source. The ring exciter is formed of a first conductive material, such as, but not limited to, copper or aluminum, etc. The ring exciter has a first end connected to an RF power source, the RF power source providing RF current to the ring exciter. The ring exciter has a second end connected to ground to allow current to flow. In some embodiments, the ring exciter may have a plurality of turns or loops. In block 1304, the ring exciter is inductively coupled to a ring applicator at a resonant frequency. The ring applicator is physically separated from the ring exciter and is formed of a second conductive material, the second conductive material having at least one angled seam having an angle forming an upper overlap portion and a lower overlap portion separated by a high-K dielectric material. The upper overlap portion, the lower overlap portion, and the high-K dielectric material are configured to provide a capacitance in combination with an inductance of the ring applicator to form a resonant circuit. The resonant circuit is configured to resonate at the resonant frequency when the ring exciter is inductively coupled to the ring applicator. In some embodiments, the ring energizer and the ring applicator may be embedded in the ceramic material of a baffle surrounding a substrate support in a processing chamber.

[0046] In some embodiments, the method 1300 may further include cleaning the surface of the processing chamber by energizing the ring exciter and energizing a resonant frequency within the ring applicator to form a plasma to remove deposits from the surface. In some embodiments, the method 1300 may further include changing the deposition thickness of the deposition material on the substrate by energizing the ring exciter and energizing a resonant frequency within the ring applicator to form a plasma. In some embodiments, the method 1300 may further include changing the deposition thickness of the deposition material on the edge of the substrate by energizing the ring exciter and energizing a resonant frequency within the ring applicator to form a plasma, wherein the ring exciter and the ring applicator surround a substrate support of the processing chamber. In some embodiments, the method 1300 may further include adjusting the azimuthal plasma by adjusting the amount of overlap of the upper overlap portion and the lower overlap portion, by adjusting the width of the ring applicator, by adjusting the thickness of the high-K dielectric material between the upper overlap portion and the lower overlap portion, by adjusting the overlap angle of the ring applicator, and / or by adjusting the amount of RF power applied to the ring exciter. In some embodiments, the angle of the angled slot may be adjusted by the ring exciter to change the resonant frequency of the ring applicator based on the frequency of the RF power applied to the ring exciter.

[0047] Embodiments according to the present principles may be implemented in hardware, firmware, software, or any combination thereof. Embodiments may also be implemented as instructions stored using one or more computer-readable media, which may be read and executed by one or more processors. Computer-readable media may include any mechanism for storing or transmitting information in a form readable by a machine (e.g., a computing platform or a "virtual machine" running on one or more computing platforms). For example, a computer-readable medium may include any suitable form of volatile or non-volatile memory. In some embodiments, a computer-readable medium may include a non-temporary computer-readable medium.

[0048] While the foregoing is directed to embodiments of the present principles, other and further embodiments of the present principles may be devised without departing from the basic scope thereof.

Claims

1. An apparatus for forming a plasma in a processing chamber, comprising: a ring energizer formed of a first conductive material, the ring energizer having a first end electrically connected to an RF power source providing an RF current and a second end connected to ground; and A ring applicator, the ring applicator being physically separated from the ring energizer, the ring applicator being formed of a second conductive material, the second conductive material having at least one angled slot, the at least one angled slot having an angle forming an upper overlapping portion and a lower overlapping portion separated by a high-K dielectric material, the high-K dielectric material being configured to provide capacitance along with an inductance of the ring applicator to form a resonant circuit, the resonant circuit being configured to resonate when the ring energizer flows an RF current, the RF current inductively exciting the ring applicator to a resonant frequency, the resonant frequency forming an azimuthal plasma from the ring applicator.

2. The apparatus of claim 1, wherein the angle is from about 1 degree to about 4 degrees.

3. The apparatus of claim 1, wherein the high-K dielectric material has a thickness of about 1 micron or greater, the thickness separating the at least one corner seam by about 1 micron or greater.

4. The apparatus of claim 1, wherein the RF power source provides a power of greater than zero to about 5 kW to the ring exciter.

5. The apparatus of claim 1, wherein the ring activator is positioned below the ring applicator.

6. The apparatus of claim 1, wherein the first conductive material and the second conductive material are aluminum.

7. The apparatus of claim 1, wherein the high-K dielectric material is applied to at least a portion of the ring applicator.

8. The apparatus of claim 1, wherein the high-K dielectric material is an insulator located between the upper overlapping portion and the lower overlapping portion.

9. The apparatus of claim 1, wherein the ring activator and the ring applicator are embedded in a ceramic material.

10. The apparatus of claim 1, wherein the ring energizer and the ring applicator are positioned in a baffle surrounding a substrate support of the processing chamber.

11. The device of claim 1, comprising a plurality of ring-shaped initiators or a plurality of ring-shaped applicators.

12. A method of forming a plasma in a processing chamber, comprising the steps of: Utilizing an RF power source to a ring driver, wherein the ring driver is formed of a first conductive material, the ring driver having a first terminal electrically connected to the RF power source to provide an RF current and a second terminal connected to ground; and The ring exciter is inductively coupled to a ring applicator to generate an azimuthal plasma from the ring applicator, wherein the ring applicator is physically separated from the ring exciter and the ring applicator is formed of a second conductive material having at least one angular slot having an angle forming an upper overlapping portion and a lower overlapping portion separated by a high-K dielectric material, wherein the high-K dielectric material is configured to provide capacitance together with an inductance of the ring applicator to form a resonant circuit, wherein the resonant circuit is configured to resonate at a resonant frequency when the ring exciter is inductively coupled to the ring applicator.

13. The method of claim 12, further comprising the steps of: Surfaces of a processing chamber are cleaned by energizing the ring energizer and exciting the resonant frequency within the ring applicator to form a plasma to remove deposits from the surface.

14. The method of claim 12, further comprising the steps of: The deposition thickness of the deposition material on the substrate is varied by energizing the ring exciter and exciting the resonant frequency within the ring applicator to form a plasma.

15. The method of claim 14, further comprising the steps of: The deposition thickness of the deposition material on the edge of the substrate is varied by energizing the ring energizer and exciting the resonant frequency within the ring applicator to form a plasma, wherein the ring energizer and the ring applicator surround a substrate support of the processing chamber.

16. The method of claim 12, further comprising the steps of: The azimuthal plasma is adjusted by adjusting the amount of overlap of the upper overlap portion and the lower overlap portion, by adjusting the width of the ring applicator, by adjusting the thickness of the high-K dielectric material between the upper overlap portion and the lower overlap portion, or by adjusting the amount of RF power applied to the ring exciter.

17. The method of claim 12, wherein the ring energizer and the ring applicator are embedded in a ceramic material of a baffle surrounding a substrate support in the processing chamber.

18. The method of claim 12, further comprising the steps of: The angle is adjusted to change the resonant frequency of the ring applicator based on the frequency of RF power applied to the ring exciter.

19. A non-transitory computer readable medium having instructions stored thereon, which when executed, cause a method of forming a plasma in a processing chamber to be performed, the method comprising the steps of: Exciting a ring driver using an RF power source, wherein the ring driver is formed of a first conductive material, the ring driver being electrically connected to a first terminal of the RF power source to provide an RF current and to a second terminal connected to ground; and The ring exciter is inductively coupled to a ring applicator to generate an azimuthal plasma from the ring applicator, wherein the ring applicator is physically separated from the ring exciter and the ring applicator is formed of a second conductive material having at least one angular slot having an angle forming an upper overlapping portion and a lower overlapping portion separated by a high-K dielectric material, wherein the high-K dielectric material is configured to provide capacitance together with an inductance of the ring applicator to form a resonant circuit, wherein the resonant circuit is configured to resonate at a resonant frequency when the ring exciter is inductively coupled to the ring applicator.

20. The non-transitory computer readable medium of claim 19, further comprising: varying a deposition thickness of a deposition material on an edge of a substrate by energizing the ring energizer and exciting the resonant frequency within the ring applicator to form a plasma, wherein the ring energizer and the ring applicator surround a substrate support of the processing chamber; adjusting the azimuthal plasma by adjusting an amount of overlap of the upper overlap portion and the lower overlap portion, by adjusting a width of the ring applicator, by adjusting a thickness of the high-K dielectric material between the upper overlap portion and the lower overlap portion, or by adjusting an amount of RF power applied to the ring energizer; or The angle is adjusted to change the resonant frequency of the ring applicator based on the frequency of RF power applied to the ring exciter.

Images