Semiconductor processing chamber adapter

Abstract

To provide semiconductor processing systems and methods for delivering precursors within a system and chamber.SOLUTION: A semiconductor processing system 200 comprising a processing chamber 205 includes: a remote plasma unit 210 coupled with the processing chamber; and an adapter 215 coupled between the remote plasma unit and the processing chamber. The adapter is characterized by a first end 217 and a second end 218 opposite the first end. The remote plasma unit is coupled with the adapter at the first end, where the adapter defines a first central channel 219 extending more than 50% of a length of the adapter from the first end of the adapter and defines a transition from the central channel to a plurality of apertures 221 extending at least partially through the adapter.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] Cross - Reference to Related Applications This application claims the benefit and priority of U.S. Patent Application No. 17 / 366,761, filed on July 2, 2021, entitled "SEMICONDUCTOR PROCESSING CHAMBER ADAPTER", the entire content of which is incorporated herein by reference.

[0002] This technology relates to semiconductor systems, processes, and equipment. More specifically, this technology relates to systems and methods for supplying precursors within a system and chamber.

Background Art

[0003] Integrated circuits are enabled by processes that create intricately patterned layers of material on a substrate surface. Creating patterned material on a substrate requires a controlled method for removing exposed material. Chemical etching is used for a variety of purposes, including transferring a photoresist pattern to a lower layer, thinning a layer, or narrowing the lateral dimensions of features already present on a surface. In many cases, for example, it is desirable to have an etching process that etches one material faster than another to facilitate a pattern transfer process or the removal of an individual material. Such an etching process is said to be selective to the first material. As a result of the diversity of materials, circuits, and processes, etching processes have evolved using selectivity to various materials.

[0004] The etching process can be called wet or dry, depending on the materials used in the process. In wet HF etching, silicon oxide is preferentially removed over other dielectrics and materials. However, in wet processes, it can be difficult to penetrate some of the restricted trenches, and the remaining material may be deformed. The dry etching process can penetrate complex features and trenches, but may not provide an acceptable top-to-bottom profile. Since the size of the device continues to decrease in next-generation devices, the way the system supplies precursors into and through the chamber can have an increasing impact. As the importance of process condition uniformity continues to grow, chamber design and system setup can play an important role in the quality of the resulting device.

[0005] Therefore, there is a need for improved systems and methods that can be used to produce high-quality devices and structures. These and other needs are addressed by the present technology. SUMMARY OF THE INVENTION

[0006] An exemplary semiconductor processing system may include a processing chamber. The system may include a remote plasma unit coupled to the processing chamber. The system may include an adapter coupled between the remote plasma unit and the processing chamber. The adapter may be characterized by a first end and a second end opposite the first end. The remote plasma unit may be coupled to the adapter at the first end. The adapter may define a first central channel that extends more than 50% of the length of the adapter from the first end of the adapter. The adapter may define a second central channel that extends less than 50% of the length of the adapter from the second end of the adapter. The adapter may define a transition between the first central channel and the second central channel.

[0007] In some embodiments, the transition portion defined between the first central channel and the second central channel of the adapter may include a plurality of apertures defined by the adapter and fluidly coupling the first central channel and the second central channel. Each aperture of the plurality of apertures may be characterized by a cross-sectional diameter of less than about 10 mm. The first central channel and the second central channel may be characterized by similar cross-sectional diameters. The second central channel may extend less than 10% of the length of the adapter from the second end of the adapter. The adapter may be coupled to electrical ground. The adapter may define a concave ledge between the first end and the second end. The semiconductor processing system may include a system housing disposed on the concave ledge of the adapter. The system housing may be grounded. The system may include an isolator coupled to the second end of the adapter. The isolator may be ceramic or may include ceramic. The system may include a mixing manifold coupled between the isolator and the processing chamber. The mixing manifold may be characterized by a first end and a second end opposite the first end. The mixing manifold may be coupled to the processing chamber at the second end. The mixing manifold may define a central channel passing through the mixing manifold. The mixing manifold may be electrically coupled to an RF power source.

[0008] Some embodiments of the present technology may include a semiconductor processing system. The system may include a remote plasma unit. The system may include a processing chamber. The chamber may include a gas box that defines a central channel. The chamber may include a faceplate coupled to the gas box at a first surface of the faceplate. The chamber may include a spacer coupled to the faceplate at a second surface of the faceplate opposite the first surface. The chamber may include a showerhead coupled between the spacer and a processing region of the processing chamber. The system may include an adapter coupled between the remote plasma unit and the processing chamber. The adapter may be characterized by a first end and a second end opposite the first end. The remote plasma unit may be coupled to the adapter at the first end. The adapter may define a first central channel that extends more than 50% of the length of the adapter from the first end of the adapter. The adapter may define a second central channel that extends less than 50% of the length of the adapter from the second end of the adapter. The adapter may define a transition between the first central channel and the second central channel.

[0009] In some embodiments, the system may include a mixing manifold disposed on the gas box. The adapter may be coupled between the mixing manifold and the remote plasma unit. The gas box, the faceplate, and the mixing manifold may be electrically coupled to an RF power source. The adapter may be coupled to electrical ground. The showerhead may be coupled to electrical ground. A plasma region may be defined between the showerhead and the faceplate. The transition defined between the first central channel and the second central channel of the adapter may include a plurality of apertures defined by the adapter and fluidly coupling the first central channel and the second central channel. The adapter may define a recessed ledge between the first end and the second end. The semiconductor processing system may include a system housing disposed on the recessed ledge of the adapter. The system housing may be grounded.

[0010] Some embodiments of the present technology may include a semiconductor processing system. The system may include a remote plasma unit. The system may include a processing chamber. The processing chamber may include a gas box that defines a central channel. The processing chamber may include a faceplate coupled to the gas box at a first surface of the faceplate. The gas box and the faceplate may be coupled to an RF power source. The chamber may include a spacer coupled to the faceplate at a second surface of the faceplate opposite the first surface. The chamber may include a showerhead coupled between the spacer and a processing region of the processing chamber. The showerhead may be coupled to electrical ground. The system may include an adapter coupled between the remote plasma unit and the processing chamber. The adapter may be characterized by a first end and a second end opposite the first end. The remote plasma unit may be coupled to the adapter at the first end. The adapter may define a first central channel that extends more than 50% of the length of the adapter from the first end of the adapter. The adapter may define a second central channel that extends less than 50% of the length of the adapter from the second end of the adapter. The adapter may define a transition between the first central channel and the second central channel. The adapter may be coupled to electrical ground. In some embodiments, the adapter may define a concave ledge between the first end and the second end. The semiconductor processing system may include a system housing disposed on the concave ledge of the adapter. The system housing may be grounded.

[0011] Such technology may provide a number of benefits over conventional systems and techniques. For example, the present technology may utilize a limited number of components as compared to conventional designs. Further, by configuring chamber components for a combined plasma system, parasitic or stray plasmas may be controlled or prevented. These and other embodiments, along with many of their advantages and features, will be described in more detail below in conjunction with the following description and the accompanying figures.

[0012] A further understanding of the nature and advantages of the disclosed technology can be achieved by referring to the remainder of this specification and the drawings.

Brief Description of the Drawings

[0013]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Best Mode for Carrying Out the Invention

[0014] Some of the figures are included as schematic diagrams. It should be understood that the figures are for illustrative purposes and are not to be considered to be to scale unless specifically stated to be so. Further, as schematic diagrams, the figures are provided to aid understanding and may not include all aspects or information compared to an actual representation and may include those exaggerated for illustrative purposes.

[0015] In the accompanying drawings, like components and / or features may have the same reference labels. Further, various components of the same type may be distinguished by a letter following the reference label to distinguish like components. If only the first reference label is used herein, this description is applicable to any of the like components having the same first reference label regardless of the letter.

[0016] The present technology includes a semiconductor processing system, a chamber, and components for performing semiconductor manufacturing processes. Many dry etching processes performed during semiconductor manufacturing may involve multiple precursors. These etchants, when activated and combined in various ways, can be supplied to a substrate to remove or change the appearance of the substrate. Conventional processing systems can provide precursors for deposition or etching, for example, in multiple ways. One way to provide enhanced precursors is to pass all of the precursors through a remote plasma unit prior to supplying the precursors to a substrate, such as a wafer, through a processing chamber for processing. However, a problem with this process is that the power used to ignite the plasma can affect the process being performed depending on the amount of dissociation that occurs. For example, in some processes, a large amount of dissociation of a hydrogen-containing precursor may be beneficial, but less dissociation of a fluorine-containing precursor may allow for more controlled etching. Further, recombination can become a greater issue depending on the amount of movement between the remote plasma unit and the substrate.

[0017] Conventional processing may also supply one precursor through a remote plasma apparatus for plasma processing and supply another precursor directly to the chamber. However, a problem with this process is that mixing of the precursors can be difficult, may not provide adequate control over etchant generation, and may not provide a uniform etchant to the wafer or substrate. This can result in the process not being performed uniformly across the surface of the substrate and may cause problems with the apparatus as patterning and formation continue.

[0018] Additional processes for plasma formation can involve generating capacitively coupled plasma within a chamber, such as within the chamber or in a remote region within the processing space. Wafer-level plasma can impact delicate features and may affect chemical etching. Generating remote plasma within the scope of the processing space can offer several advantages. For example, low-power plasma can be generated to control ionization, and since this generation is closer to the substrate being processed, the issues due to recombination over the travel distance may not be overly significant. Additionally, plasma species can be distributed more uniformly radially outward than from the supply of a remote plasma unit, allowing precursors to be supplied through a centrally located tube. However, generating plasma within a chamber where some other components are coupled to a power source but a certain lid stack component may be grounded can increase parasitic plasma formation. As an example further discussed below, since the RPS unit can operate at a lower power frequency than the internal capacitively coupled plasma, the RPS unit can effectively operate as a ground, which can cause plasma generation upstream at a remote location within the chamber, not only damaging components detrimentally but also affecting etching uniformity.

[0019] The present technology can overcome these problems by utilizing components and systems configured to limit or prevent plasma generation outside of desired locations, and by providing a chamber configured to provide a composite plasma generation capability for improving the flexibility of the system. The system of the present technology may also include a configuration of components that controls the electrical coupling between components to provide a composite plasma generation capability.

[0020] The remaining disclosure generally identifies a particular etching process that utilizes the disclosed technology, but it will be readily understood that the systems and methods are equally applicable to deposition and cleaning processes that may be performed in the described chambers. Accordingly, this technology should not be considered to be so limited with respect to use only in an etching process or chamber. Prior to describing aspects and variations of components for this system according to embodiments of the present technology, one possible system and chamber in which the present technology can be used will be discussed in this disclosure.

[0021] FIG. 1 shows a top view of one embodiment of a processing system 100 for deposition, etching, annealing, and curing chambers according to an embodiment. In this figure, a pair of front-opening unified pods (FOUPs) 102 are received by a robotic arm 104 and placed in a low-pressure holding area 106 before being inserted into one of the substrate processing chambers 108a-f positioned in tandem sections 109a-c, providing substrates of various sizes. A second robotic arm 110 can be used to transport substrate wafers from the holding area 106 to and from the substrate processing chambers 108a-f. Each of the substrate processing chambers 108a-f can be equipped to perform several substrate processing steps, including the dry etching processes described herein, in addition to cyclic layer deposition (CLD), atomic layer deposition (ALD), chemical vapor deposition (CVD), physical vapor deposition (PVD), etching, pre-cleaning, degassing, orientation, and other substrate processes.

[0022] The substrate processing chambers 108a - f may include one or more system components for depositing, annealing, curing, and / or etching a dielectric film on a substrate wafer. In one configuration, two pairs of processing chambers, e.g., 108c - d and 108e - f, may be used to deposit a dielectric material on the substrate, and a third pair of processing chambers, e.g., 108a - b, may be used to etch the deposited dielectric. In another configuration, all three pairs of chambers, e.g., 108a - f, may be configured to etch a dielectric film on the substrate. Any one or more of the described processes may be performed in chambers separate from the manufacturing system shown in different embodiments. It will be understood that additional configurations of deposition, etching, annealing, and curing chambers for dielectric films by system 100 are possible.

[0023] FIG. 2 shows a schematic cross - sectional view of an exemplary processing system 200 according to an embodiment of the present technology. The system 200 may include a processing chamber 205 and a remotely - located plasma system ( "RPS") unit 210, which is partially shown. The remotely - located plasma unit 210 may be coupled to the processing chamber 205 having one or more components. The remotely - located plasma unit 210 may be coupled to one or more of an adapter 215, an isolator 225, and a mixing manifold 230. The mixing manifold 230 may be coupled to the upper portion of the processing chamber 205, and this inlet may be coupled to the processing chamber 205.

[0024] The adapter 215 may be coupled to the RPS unit in an embodiment. The adapter 215 may be characterized by a first end 217 and a second end 218 opposite the first end, in which case the RPS unit 210 is installed on the first end 217 of the adapter 215. The adapter 215 may define one or more central channels passing through portions of the adapter 215. For example, from the first end 217, a central channel 219, i.e., a first central channel, may extend at least partially through the adapter 215 toward the second end 218 and may extend through any length of the adapter 215. The central channel 219 may extend more than half the length through the adapter 215. By configuring the adapter 215 such that the first central channel extends a length greater than 50% of the length of the adapter, as further described below, parasitic plasma formation within the adapter may be limited or prevented.

[0025] The adapter 215 may define a transition from the central channel 219 to a plurality of apertures 221 that may extend at least partially through the adapter 215, and may define a base of the first central channel 219 within the adapter 215. The transition may occur, for example, at a location below an intermediate point through the adapter closer to the second end 218 of the adapter 215. For example, the apertures 221 may extend from the base of the first central channel 219 toward the second end 218 of the adapter 215 and may extend to fluidly couple with a second central channel 223. The second central channel 223 may extend from the plurality of apertures 221 to the second end 218 of the adapter 215. The second central channel 223 may extend less than about 50% of the length of the adapter 215 in the direction of flow from the RPS unit, less than about 40% of the length of the adapter, less than about 30% of the length of the adapter, less than about 20% of the length of the adapter, less than about 10% of the length of the adapter, or less than this.

[0026] By restricting the length of the second central channel through the adapter, parasitic plasma formation can be restricted within the adapter. Similarly, the aperture 221 can be characterized by a diameter configured to restrict plasma formation within the aperture by the hollow cathode effect. For example, in some embodiments, the aperture 221 can be characterized by a cross-sectional diameter of less than about 50% of the diameter of the central channel 219, less than about 40%, less than about 30%, less than about 20%, less than about 10%, less than about 5%, or less than this diameter of the central channel 219. The second central channel 223 can be characterized by a cross-sectional diameter similar to that of the first central channel 219 in some embodiments, although the diameter can be greater than or less than the diameter of the first central channel 219 in some embodiments.

[0027] Based on the plasma output utilized in the processing system, the aperture 221 can be characterized by a cross-sectional diameter of less than about 10 mm, less than about 9 mm, less than about 8 mm, less than about 7 mm, less than about 6 mm, less than about 5 mm, less than about 4 mm, or less than this cross-sectional diameter. Thereby, plasma generation within the aperture can be restricted or prevented, so that plasma formation upstream of the mixing manifold 230 in some embodiments can be controlled. The adapter 215 can also define a ledge as further described below, on which a system cover or housing 220 can be installed as shown. The housing can be coupled to electrical ground as shown, so the adapter 215 can be coupled to electrical ground in some embodiments of the present technology.

[0028] The adapter 215 may be made of ceramic or an insulating material, but in some embodiments, the adapter 215 may be made of or include aluminum, such as aluminum oxide, treated aluminum on one or more surfaces, or other materials such as nickel or nickel-plated aluminum. For example, the inner surface of the adapter 215 may be coated with one or more materials to protect the adapter 215 from damage that may be caused by plasma emissions from the remote plasma unit 210. The inner surface of the adapter 215 may be, for example, inert to plasma emissions of fluorine and may be anodized with various materials that may include, for example, yttrium oxide or barium titanate.

[0029] An isolator 225 may be coupled to the adapter 215, and the isolator 225 may be coupled to the second end 218 of the adapter 215. The isolator 225 may be or include ceramic and may operate to electrically insulate the adapter 215 from a mixing manifold 230 that may operate at a different potential than the adapter 215 in some embodiments of the present technology. The isolator 225 may define a central aperture 227 therethrough. The central aperture 227 may be characterized by a tapered shape through the isolator 225 from a portion proximate to the second central channel 223 of the adapter 215 to the opposite side of the isolator 225. A portion of the central aperture 227 proximate to the second central channel 223 may be characterized by a diameter equal to or similar to the diameter of the second central channel 223. The central aperture 227 may be characterized by a taper ratio of about 10% or more along the length of the isolator 225, and in embodiments, about 20% or more, about 30% or more, about 40% or more, about 50% or more, about 60% or more, about 70% or more, about 80% or more, about 90% or more, about 100% or more, about 150% or more, about 200% or more, about 300% or more, or more of a taper ratio.

[0030] The mixing manifold 230 may be coupled to the isolator 225 at a first end 232 or a first surface, and may be coupled to the chamber 205 at a second end 234 opposite the first end 232. The mixing manifold 230 may define a central channel 236 that may extend from the first end 232 to the second end 234 and may be configured to supply a precursor into the processing chamber 205. The mixing manifold 230 may also be configured to incorporate additional precursors along with the mixed precursors supplied from the adapter 215. The mixing manifold 230 may provide a second stage of mixing within the system. The mixing manifold 230 may define ports along the exterior of the mixing manifold 230, such as along a side or sidewall of the mixing manifold 230. The mixing manifold 230 may also define one or more trenches within a first surface 232 of the mixing manifold 230, which may provide fluid access from the ports to the central channel 236.

[0031] The central channel 236 may be characterized by a first portion that extends from the first end 232 to the flare portion. The first portion of the central channel 236 may be characterized by a cylindrical profile and may be characterized by a diameter that is the same as or greater than the exit of the central aperture 227 of the isolator 225. The flare portion, in embodiments, may be characterized by a flare ratio of about 10% or more, about 20% or more, about 30% or more, about 40% or more, about 50% or more, about 60% or more, about 70% or more, about 80% or more, about 90% or more, about 100% or more, about 150% or more, about 200% or more, about 300% or more, or more. The mixing manifold 230 may be made of the same or different materials as the adapter 215 in embodiments. For example, the mixing manifold 230 may include nickel that can provide suitable protection for all precursors that may contact portions of the mixing manifold. Contrary to the prior art, recombination-related problems may not occur because fluorine plasma emissions may already be mixed upstream of the mixing manifold. For example, without wishing to be bound by any particular theory, nickel may catalyze the recombination of fluorine radicals to diatomic fluorine, which can contribute to material loss on the substrate in the prior art. When the fluorine emissions are mixed before being supplied to nickel, nickel plating, or a coated component, the concentration of the fluorine emissions is reduced and the features are further protected at the substrate level, so this process may be limited.

[0032] Chamber 205 may include several components in a stacked arrangement. The chamber stack may include a gas box 240, a blocker plate 250, a faceplate 260, a spacer 265, an optional ion suppression element 270, a showerhead 280, and a lid spacer 285. The components may be utilized to distribute a precursor or a set of precursors through the chamber to provide a uniform supply to the substrate 293 for processing with an etchant or other precursor. The substrate 293 may be placed on a pedestal 295 that may be raised or lowered in different embodiments during operation or for a particular operation. In embodiments, these distribution components may each be a laminate that at least partially defines the exterior of the chamber 205.

[0033] The gas box 240 may define a chamber inlet coupled to the mixing manifold 230. A central channel 242 may be defined through the gas box 240 to supply a precursor into the chamber 205. The inlet of the gas box may be sized to be aligned with the outlet of the mixing manifold 230. For example, the inlet and / or the central channel 242 may be characterized by a diameter similar to or larger than the outlet of the mixing manifold in an embodiment. The central channel 242 may extend through the gas box 240 and may be configured to supply one or more precursors into the interior volume of the processing chamber. The gas box 240 may be included or characterized by a first surface 243 such as an upper surface and a second surface 245 opposite the first surface 243 such as the bottom surface of the gas box 240. A heater or weldment defining a channel for receiving a cooling fluid for temperature control may be coupled to the upper surface 243.

[0034] The second surface 245 of the gas box 240 may be coupled to a blocker plate 250 to which, for example, the gas box may be attached or coupled. The blocker plate 250 may be characterized by a diameter equal to or similar to the diameter of the protrusion of the gas box 240. The blocker plate 250 may define a plurality of apertures therethrough, only a sample of which is shown, which may allow for the distribution of precursors such as etchant from the central channel 242 of the gas box and may begin to distribute the precursors through the chamber 205 for uniform supply to the substrate. The faceplate 260 may include a first surface 262 and a second surface 264 opposite the first surface 262. The faceplate 260 may be coupled to the gas box 240 at the first surface 262 such that it may engage the outer annular portion of the gas box. The faceplate 260 may define a recess 263 within the first surface 262 that may define a volume in which the blocker plate 250 may be disposed, within which the gas box 240 and the central channel 242 may extend.

[0035] The blocker plate may maintain a distance from the faceplate to allow for further distribution after the precursor has been distributed through the blocker plate. In some embodiments, one or more of the components of the gas box, the blocker plate, and the faceplate may be in direct physical and electrical contact with a mixing manifold. The components may be electrically coupled to a power source, such as an RF power source 255, that may provide power to the components to generate plasma within the region defined between the faceplate and other downstream components. A spacer 265 may be disposed between the faceplate and other components to electrically insulate the faceplate from the other components to create capacitively coupled plasma therebetween. Thus, the spacer 265 may be a dielectric component, such as ceramic or other insulating material, in some embodiments of the present technology.

[0036] The ion suppression element 270 may be positioned proximate to the second surface 264 of the faceplate 260 and may be coupled on the opposite side of the spacer 265. The ion suppression element 270, together with the faceplate 260, may define a remote plasma region 267 within the processing chamber when radially defined by the spacer 265. This region may be referred to as remote in view that the substrate being processed cannot be directly exposed to the plasma emissions generated in the plasma region 267. Thus, the plasma impact on the wafer can be limited or prevented. Further, the ion suppression element 270 may be configured to reduce ion movement into the processing region of the chamber 205 that houses the substrate. The ion suppression element 270 may define a plurality of apertures through the structure. The showerhead 280 may be disposed adjacent to the ion suppression element 270 and the ion suppression element may be installed on the showerhead 280. Any perforated plate or manifold may be included in embodiments of the present technology, although in some embodiments the showerhead 280 may be a dual-channel showerhead as shown. The showerhead may include two plates coupled together to define a central volume through which separate precursors may flow, such as from external ports or channels. The bottom plate facing the processing region and the like may define apertures providing fluid access from the volume, while the top plate may prevent upstream access from the upper plate. The top and bottom plates may also define axially aligned holes to create channels extending through the showerhead. Thus, the showerhead may enable precursors to be supplied from upstream through the showerhead, and the precursors may not interact with the precursors supplied through the internal volume defined by the showerhead until each of the precursors exits the bottom plate of the showerhead and enters the processing region.

[0037] The showerhead 280 may be installed on a lid spacer 285 that can at least partially define a processing area where a substrate 293 can be disposed for semiconductor processing. The lid spacer 286 may be an insulating material or a dielectric material in some embodiments, but in embodiments, the component may also have conductivity. In some embodiments, one or more of the components of the ion suppression element 270, the showerhead 280, and the lid spacer 285 may be in direct physical and electrical contact. The components may be electrically coupled to an electrical ground that can control internal plasma formation and limit the formation into the remote plasma region 267 between the panel 260 that can be motorized and the ion suppression element 270 that can be grounded. Therefore, the system 200 may include both an RPS unit for remote plasma generation and an area inside the chamber where plasma generation can also occur.

[0038] As described above, the mixing manifold 230 may be electrically coupled to the gas box 240 and other components of the power supply electrode. However, the adapter 215 may be grounded. In some conventional setups, such a configuration may enable plasma to be generated upstream of the gas box during operation of the power supply electrode. This can damage components and affect plasma formation in the remote plasma region 267, which may reduce the uniformity of etching and processing on the substrate. Further, the RPS unit can often operate at a lower frequency than a capacitively coupled plasma power supply, which can allow backflowing plasma to enter and damage the RPS unit. For example, the power supply 255 can operate at any number of higher frequencies, such as 13.56 MHz in one non-limiting example, while the RPS unit can operate at a lower frequency, such as below a few hundred kilohertz. In conventional setups that may not include the additional grounding discussed herein, the RPS unit can effectively operate as an additional grounding path for the power supply electrode due to the mismatch in operating frequencies. Components can be damaged if plasma is subsequently generated upstream and enters the RPS unit. However, the present technology can limit or prevent these effects through the configuration and coupling of components upstream of the gas box. By utilizing components according to the configuration of embodiments of the present technology, the adapter may be grounded to prevent plasma intrusion into the RPS unit, and the components may be configured to limit or prevent plasma generation.

[0039] Figure 3 shows a cross-sectional view of a portion of an exemplary processing system 200 according to some embodiments of the present technology. The figure may show additional aspects of the previously discussed components and may include any features, aspects, or characteristics of any of the previously described components. As previously discussed, the RPS unit 210 may be disposed on a first end of the adapter 215, and the adapter 215 may be coupled to the isolator 225 at a second end of the adapter. The adapter 215 may also define a ledge 305 between a first end of the adapter that may include a mating flange for the RPS unit as shown, and a second end of the adapter that may include a mating flange for lower components as discussed below. The ledge 305 may be a recessed ledge from the outer diameter of the adapter, may be spaced along the length of the adapter, and will be disposed along a portion where the first central channel 219 is defined.

[0040] The system housing 220 may be disposed on the ledge 305 as shown and may be coupled to the adapter. As previously explained, the system housing may be grounded, thereby electrically grounding the adapter when coupled to the adapter 215. This may limit or prevent plasma from being generated in the RPS unit based on the operation of the downstream electrode. The system housing may be directly coupled to the adapter 215, such as by a connector 307 as shown. This may ensure that the components remain in contact. The connector 307 may be any type of coupling including bolts installed in bushings as shown, but it should be understood that any coupler or fastener may be used to maintain physical contact between the components. To maintain symmetry for electrical coupling, in some embodiments, a channel 309 may be defined around the ledge 305. An RF strap or other conductive material may be installed within the channel to provide contact along the adapter to the housing.

[0041] The flange 310 may be defined at the second end of the adapter 215 and may define one or more apertures to enable coupling with additional components. As shown, the adapter 215 may be coupled with the gas box 240 along with the isolator 225 and the mixing manifold 230. An elastomeric element or O-ring may be disposed between components to fluid-seal the components during operation. However, as previously explained, the adapter 215 may be grounded, while the mixing manifold 230 and the gas box 240 may be coupled with a power source to operate as a power supply electrode for plasma generation. In some embodiments of the present technology, to limit short circuits, the connection components used to couple system components may be electrically insulated from the adapter 215. As shown, one or more apertures may be defined in each of the components to receive bolts, fasteners, or other coupling components. However, the bushing 212 may be installed and recessed as shown in each aperture of the adapter 215, whereby contact or electrical coupling between the bolt and the grounded adapter may be restricted or prevented. Further, the apertures defined through the adapter may be characterized by a diameter that may be at least twice the diameter of the coupling component, whereby electrical short circuits between materials may be restricted. In some embodiments, the bushing 212 may extend completely through the apertures in the adapter and may be installed in or within the isolator.

[0042] As described above, due to the grounded adapter, plasma generation upstream of the powered mixing manifold can be a problem of the prior art. However, the present technology can include an adapter configured to limit plasma generation within the components. For example, as previously described, the second central channel 223 can extend less than about 50% of the length of the adapter, less than about 20% of the length of the adapter, less than about 10% of the length of the adapter, or less than that in the direction of flow from the RPS unit, whereby the available space for plasma generation can be controlled. For example, the length of the second portion can be maintained at less than about 5 cm, less than about 4 cm, less than about 3 cm, less than about 2 cm, less than about 1 cm, less than about 9 mm, less than about 8 mm. Less than about 7 mm, less than about 6 mm, less than about 5 mm, less than about 4 mm, less than about 3 mm, less than about 2 mm, or less than that, in which case the chamber can be operated at a pressure of several tens of Torr or less.

[0043] Using an adapter with an increased distance to the components in this electrical configuration in the prior art can result in a hollow cathode effect in that region, which can increase the current density within that area. This can lead to an improvement in ionization that can advance plasma generation within the components. The present technology can limit the distance to any of the above ranges, whereby plasma generation during the operation of the functioning capacitively coupled electrode can be limited or prevented. By reducing the spacing, the mean free path length can be controlled before collision with the transition portion, whereby ionization in the components can be prevented. Similarly, the aperture 221 defined by the transition between the first central channel 219 and the second central channel 223 can be sized to prevent the hollow cathode effect, and in some embodiments of the present technology, to any of the ranges listed above, for example, less than about 10 mm, less than about 9 mm, less than about 8 mm, less than about 7 mm, less than about 6 mm, less than about 5 mm, less than about 4 mm, less than about 3 mm, or less than that.

[0044] The central aperture 227 of the isolator 225 may also affect the possibility of plasma generation within the space defined by the central aperture, which can create a volume between the electric mixing manifold and the grounded adapter. Therefore, depending on the power being supplied and the pressure at which the chamber can operate, in some embodiments, the central aperture 227 may be changed to a plurality of apertures. FIG. 4 shows a cross-sectional view of a portion of an exemplary processing system 200 according to some embodiments of the present technology. The figure may show additional aspects of the previously discussed components and may include any features, aspects, or characteristics of any of the components described above. The figure may show additional isolator configurations according to some embodiments of the present technology.

[0045] The isolator 405 may include any features, aspects, or characteristics of the isolator 225, as discussed above, and may include a plurality of channels 410 instead of a central aperture, as previously described. Since the insulating isolator defines the space between the capacitively coupled electrodes, plasma generation can occur within the volume defined by the isolator. The diameter of the single centrally defined aperture may be reduced in some embodiments, but depending on the operating parameters of the chamber, such as pressure and plasma electrode power, plasma generation may not be prevented while maintaining an appropriate flow through the components. By including a plurality of channels 410, sufficient flow through the isolator can be maintained and plasma generation can be prevented. For example, the aperture may be maintained at any of the diameters described above for the aperture 221 defined by the transition in the adapter. Further, as shown, the channels 410 may be laterally offset from the central axis through any aperture 221 in the transition in the adapter. Therefore, in some embodiments, there may be no channel 410 axially aligned with any aperture 221 of the adapter. This may also limit the mean free path length in any direction prior to collision, thereby preventing plasma generation between the mixing manifold and the adapter. By utilizing the components and configurations according to embodiments of the present technology, the RPS unit and capacitively coupled plasma can be utilized to improve the operational flexibility over conventional systems.

[0046] Figure 5 shows the steps of a method 500 for performing steps in a system according to some embodiments of the present technology. Method 500 may be executed in system 200, which may improve the flexibility of processing while protecting components from etchant damage and restricting upstream plasma generation during capacitively coupled plasma formation. Method 500 may include some steps of plasma processing, and may describe steps that can be executed in an exemplary system, but the steps may be executed in any number of processes in a different order. Although an etching process is described, it should be understood that the processing may equally include a cleaning process or a deposition process.

[0047] Method 500 may include forming plasma in the RPS unit in optional step 505. In step 510, the plasma emissions may flow into the processing chamber. The plasma emissions may flow through any of the components included between the RPS unit and the chamber, and in some embodiments, additional precursors may flow into one or more of the components, for example, through a mixing manifold, and be mixed with the plasma emissions. In optional step 515, the plasma emissions and materials may flow through the chamber and perform steps on a substrate disposed within the chamber or within the processing region of the chamber.

[0048] Method 500 may also include forming plasma in the processing chamber in step 520, for example, between the faceplate and the ion suppression element as previously described. In some embodiments, the plasma may be contained within a remote plasma region defined within the processing chamber, and forming the plasma upstream from the remote region, such as within an isolator or adapter as previously described, may be restricted or prevented. In optional step 525, the plasma emissions may flow into the processing region and act on the processing chamber or a substrate disposed within the processing region. By utilizing the components and chamber configurations as previously described, improved plasma uniformity and processing accuracy may be provided.

[0049] In the foregoing description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of various embodiments of the present technology. However, it will be apparent to those skilled in the art that certain embodiments may be practiced without some of these specific details or with additional details.

[0050] Although several embodiments have been disclosed, those skilled in the art will recognize that various modifications, alternative configurations, and equivalents may be used without departing from the spirit of the embodiments. Further, to avoid unnecessarily obscuring the present technology, some well-known processes and elements are not described. Therefore, the foregoing description should not be taken as limiting the scope of the present technology.

[0051] When a range of values is given, it is to be understood that each intervening value, to the smallest fraction of the unit of the lower limit, unless the context clearly dictates otherwise, is specifically disclosed between the upper and lower limits of that range. Any stated value or intervening value within the stated range, and any narrower range between any other stated or intervening value within the stated range, are included. The upper and lower limits of these smaller ranges may independently be included in or excluded from the range, and ranges including any one, neither, or both of the specifically excluded upper or lower limits of the stated range, in accordance with each such specifically excluded upper or lower limit, are also included in the present technology. When the stated range includes one or both of the upper and lower limits, ranges excluding either one or both of those included upper and lower limits are also included.

[0052] As used in this specification and the appended claims, the singular forms "a", "an", and "the" include plural references unless the context clearly dictates otherwise. Thus, for example, reference to "an aperture" includes a plurality of such apertures, reference to "the precursor" includes reference to one or more precursors and their equivalents known to those skilled in the art, and the like.

[0053] Also, as used in this specification and the following claims, the terms "comprise", "comprising", "contain", "containing", "include", and "including" are intended to specify the presence of the stated feature, integer, component, or step, but do not preclude the presence or addition of one or more other features, integers, components, steps, acts, or groups.

Claims

1. 1. A semiconductor processing system comprising: a processing chamber; a remote plasma unit coupled to the processing chamber; an adapter coupled between the remote plasma unit and the processing chamber; 1. A semiconductor processing system comprising: a semiconductor processing unit configured to receive a plasma from a remote plasma unit; a first end of the adapter and a second end of the adapter opposite the first end; a remote plasma unit coupled to the adapter at the first end; a first central channel extending more than 50% of a length of the adapter from the first end of the adapter; a second central channel extending less than 50% of the length of the adapter from the second end of the adapter; and a transition between the first and second central channels.

2. 2. The semiconductor processing system of claim 1, wherein the transition defined between the first central channel and the second central channel of the adapter includes a plurality of apertures defined by the adapter and fluidly coupling the first central channel and the second central channel.

3. 3. The semiconductor processing system of claim 2, wherein each aperture of said plurality of apertures is characterized by a cross-sectional diameter of about 10 mm or less.

4. 10. The semiconductor processing system of claim 1, wherein said first central channel and said second central channel are characterized by a similar cross-sectional diameter.

5. 2. The semiconductor processing system of claim 1, wherein said second central channel extends less than 10% of said length of said adapter from said second end of said adapter.

6. 10. The semiconductor processing system of claim 1, wherein said adapter is coupled to an electrical ground.

7. the adapter defines a recessed ledge between the first end and the second end, and the semiconductor processing system comprises:

7. The semiconductor processing system of claim 6, further comprising a system housing mounted on said recessed ledge of said adapter, said system housing being grounded.

8. The semiconductor processing system of claim 1 further comprising an isolator coupled to said second end of said adapter.

9. The semiconductor processing system of claim 8 , wherein the isolator comprises a ceramic.

10. 10. The semiconductor processing system of claim 8, further comprising a mixing manifold coupled between said isolator and said processing chamber.

11. 11. The semiconductor processing system of claim 10, wherein the mixing manifold is characterized by a first end and a second end opposite the first end, the mixing manifold being coupled to the processing chamber at the second end, and the mixing manifold defining a central channel through the mixing manifold.

12. 12. The semiconductor processing system of claim 11, wherein the mixing manifold is electrically coupled to an RF power source.

13. 1. A semiconductor processing system comprising: A remote plasma unit; A processing chamber comprising: a gas box defining a central channel; a face plate coupled to the gas box at a first surface; a spacer coupled to the face plate at a second surface of the face plate opposite the first surface of the face plate; and a processing chamber including a showerhead coupled between the spacer and a processing region of the processing chamber; an adapter coupled between the remote plasma unit and the processing chamber; 1. A semiconductor processing system comprising: a semiconductor processing unit configured to receive a plasma from a remote plasma unit; a first end of the adapter and a second end of the adapter opposite the first end; a remote plasma unit coupled to the adapter at the first end; a first central channel extending more than 50% of a length of the adapter from the first end of the adapter; a second central channel extending less than 50% of the length of the adapter from the second end of the adapter; and a transition between the first and second central channels.

14. 14. The semiconductor processing system of claim 13, further comprising a mixing manifold mounted on said gas box, said adapter being coupled between said mixing manifold and said remote plasma unit.

15. 15. The semiconductor processing system of claim 14, wherein said gas box, said faceplate, and said mixing manifold are electrically coupled to an RF power source.

16. 14. The semiconductor processing system of claim 13, wherein the adapter is coupled to an electrical ground, the showerhead is coupled to an electrical ground, and a plasma region is defined between the showerhead and the faceplate.

17. 14. The semiconductor processing system of claim 13, wherein the transition defined between the first central channel and the second central channel of the adapter includes a plurality of apertures defined by the adapter and fluidly coupling the first central channel and the second central channel.

18. the adapter defines a recessed ledge between the first end and the second end, and the semiconductor processing system comprises:

14. The semiconductor processing system of claim 13, further comprising a system housing mounted on said recessed ledge of said adapter, said system housing being grounded.

19. 1. A semiconductor processing system comprising: A remote plasma unit; A processing chamber comprising: a gas box defining a central channel; a face plate coupled to the gas box at a first surface, the gas box and the face plate being coupled to an RF power source; a spacer coupled to the face plate at a second surface of the face plate opposite the first surface of the face plate; and a processing chamber including a showerhead coupled between the spacer and a processing region of the processing chamber, the showerhead coupled to an electrical ground; an adapter coupled between the remote plasma unit and the processing chamber; 1. A semiconductor processing system comprising: an adapter characterized by a first end and a second end opposite the first end; the remote plasma unit is coupled to the adapter at the first end; the adapter defines a first central channel extending more than 50% of a length of the adapter from the first end of the adapter; the adapter defines a second central channel extending less than 50% of the length of the adapter from the second end of the adapter; the adapter defines a transition between the first and second central channels; and the adapter is coupled to an electrical ground.

20. the adapter defining a recessed ledge between the first end and the second end, and the semiconductor processing system comprising:

20. The semiconductor processing system of claim 19, further comprising a system housing mounted on said recessed ledge of said adapter, said system housing being grounded.

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