Semiconductor Processing Chamber Adapter

Abstract

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.

Description

[Technical field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of and priority to U.S. patent application Ser. No. 17 / 366,761, filed July 2, 2021, entitled “SEMICONDUCTOR PROCESSING CHAMBER ADAPTER,” the entire contents of which are incorporated herein by reference.

[0002] The present technology relates to semiconductor systems, processes, and equipment. More specifically, the present technology relates to systems and methods for delivering precursors in systems and chambers. [Background technology]

[0003] Integrated circuits are made possible by processes that produce intricately patterned layers of material on a substrate surface. Producing patterned materials on a substrate requires a controlled method for removing exposed material. Chemical etching is used for a variety of purposes including transferring a pattern of photoresist to an underlying layer, thinning a layer, or narrowing the lateral dimensions of features already present on a surface. It is often desirable to have an etching process that etches one material faster than another, for example, facilitating the pattern transfer process or removal of individual materials. 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 with selectivity to a variety of materials.

[0004] Etch processes can be referred to as wet or dry based on the materials used in the process. Wet HF etching preferentially removes silicon oxide over other dielectrics and materials. However, wet processes can have difficulty penetrating some constrained trenches and may sometimes distort the remaining material. Dry etch processes can penetrate complex features and trenches but may not provide acceptable top-to-bottom profiles. As equipment sizes continue to shrink in next generation equipment, the way the system delivers precursors into and through the chamber can have an increasing impact. As uniformity of process conditions continues to become more important, chamber design and system setup can play a key role in the quality of the resulting equipment.

[0005] Thus, 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, a transition defined between the first and second central channels of the adapter may include a plurality of apertures defined by the adapter and fluidly coupling the first and second central channels. Each aperture of the plurality of apertures may be characterized by a cross-sectional diameter of less than about 10 mm. The first and second central channels 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 an electrical ground. The adapter may define a recessed ledge between the first and second ends. The semiconductor processing system may include a system housing seated on the recessed 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 or may include a 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 process chamber at the second end. The mixing manifold may define a central channel 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 defining 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 of the faceplate. 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 extending more than 50% of the length of the adapter from the first end of the adapter. The adapter may define a second central channel extending 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 mounted on the gas box. The adapter may be coupled between the mixing manifold and the remote plasma unit. The gas box, faceplate, and mixing manifold may be electrically coupled to an RF power source. The adapter may be coupled to an electrical ground. The showerhead may be coupled to an electrical ground. A plasma region may be defined between the showerhead and the faceplate. A transition defined between the first and second central channels of the adapter may include a plurality of apertures defined by the adapter and fluidly coupling the first and second central channels. The adapter may define a recessed ledge between the first and second ends. The semiconductor processing system may include a system housing mounted 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 defining 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 of the faceplate. The chamber may include a showerhead coupled between the spacer and a processing region of the processing chamber. The showerhead may be coupled to an 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 extending more than 50% of a length of the adapter from the first end of the adapter. The adapter may define a second central channel extending 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 an electrical ground. In some embodiments, the adapter may define a recessed ledge between the first end and the second end. The semiconductor processing system may include a system housing seated on the recessed ledge of the adapter. The system housing may be grounded.

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

[0012] A further understanding of the nature and advantages of the disclosed technology may be realized by reference to the remaining portions of the specification and the drawings. [Brief description of the drawings]

[0013] [Figure 1] FIG. 1 illustrates a top view of an exemplary processing system in accordance with some embodiments of the present technique. [Diagram 2] 1 is a schematic cross-sectional view of an exemplary processing chamber in accordance with some embodiments of the present technique. [Diagram 3] 1 is a cross-sectional view of a portion of an exemplary processing chamber in accordance with some embodiments of the present technique. [Figure 4] 1 is a cross-sectional view of a portion of an exemplary processing chamber in accordance with some embodiments of the present technique. [Diagram 5] 1A-1D illustrate method steps for delivering precursors through a processing system according to some embodiments of the present technique. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] Some of the figures are included as schematic diagrams. It is understood that the figures are for illustrative purposes and should not be considered to scale unless specifically stated to be to scale. Furthermore, as schematic diagrams, the figures are provided to aid in understanding and may not include all aspects or information compared to realistic representations and may include exaggerated aspects for illustrative purposes.

[0015] In the accompanying drawings, similar components and / or features may have the same reference label. Furthermore, various components of the same type may be distinguished by following the reference label with a letter that distinguishes between the similar components. If only the first reference label is used in this specification, this description is applicable to any of the similar components that have the same first reference label, regardless of the letter.

[0016] The present technology includes semiconductor processing systems, chambers, 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, may be delivered to a substrate to remove or change aspects of the substrate. Conventional processing systems may provide precursors for deposition or etching, etc., in multiple ways. One way to provide enhanced precursors is to provide all of the precursors through a remote plasma unit before delivering them through a processing chamber to a substrate, such as a wafer, for processing. However, a problem with this process is that the power to ignite the plasma may affect the process being performed by the amount of dissociation that occurs. For example, in some processes, a large amount of dissociation of a hydrogen-containing precursor may be beneficial, while a lesser amount of dissociation of a fluorine-containing precursor may allow for a more controlled etch. Additionally, recombination may be a greater challenge due to the amount of travel between the remote plasma unit and the substrate.

[0017] Conventional processes may also deliver one precursor through a remote plasma device for plasma processing and another precursor directly into the chamber. However, the problem with this process is that mixing of the precursors may be difficult, may not provide adequate control over etchant generation, and may not provide a uniform etchant to the wafer or substrate. This may cause the process to not run uniformly across the surface of the substrate and may cause equipment problems as the patterning and formation continues.

[0018] Additional processes for plasma formation may involve generating a capacitively coupled plasma within the chamber, such as in a remote area within the chamber or the processing space. Wafer-level plasma may bombard sensitive features and affect chemical etching. Generating a remote plasma within the confines of the processing space may provide several advantages. For example, a low-power plasma may be generated to control ionization, and recombination due to travel distance may not be as challenging because the generation is closer to the substrate being processed. Additionally, plasma species may be distributed radially outward more uniformly than a feed from a remote plasma unit, which may feed precursors through a centrally located tube. However, generating a plasma within a chamber where certain lid stack components may be grounded while other components are coupled to a power source may increase parasitic plasma formation. As an example, discussed further below, the RPS unit may operate at a lower power frequency than an internal capacitively coupled plasma, so the RPS unit may effectively operate as a ground, which may cause plasma generation upstream of a remote location within the chamber, which may adversely damage components as well as affect etch uniformity.

[0019] The present technology may overcome these problems by utilizing components and systems configured to limit or prevent plasma generation other than at desired locations, and by providing a chamber configured to provide compound plasma generation capabilities for increased system flexibility. The systems of the present technology may also include configurations of components that control electrical coupling between components to provide compound plasma generation capabilities.

[0020] While the remaining disclosure generally identifies certain etching processes utilizing the disclosed technology, 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. Thus, the technology should not be considered as so limited with respect to use with only etching processes or chambers. This disclosure discusses one possible system and chamber in which the technology may be used, before describing component aspects and modifications to this system in accordance with embodiments of the technology.

[0021] FIG. 1 illustrates a top view of one embodiment of a deposition, etch, bake, and cure chamber processing system 100, according to an embodiment. In this view, a pair of front opening unified pods (FOUPs) 102 provide substrates of various sizes that are received by a robotic arm 104 and placed in a low pressure holding area 106 before being placed in one of the substrate processing chambers 108a-f positioned in tandem sections 109a-c. A second robotic arm 110 may be used to transport substrate wafers from the holding area 106 to the substrate processing chambers 108a-f and vice versa. Each substrate processing chamber 108a-f can be equipped to perform several substrate processing steps, including 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, as well as the dry etching processes described herein.

[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 a 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 a substrate. Any one or more of the described processes may be performed in separate chambers from the fabrication system shown in different embodiments. It will be understood that additional configurations of deposition, etching, annealing, and curing chambers for dielectric films with the system 100 are contemplated.

[0023] 2 shows a schematic cross-sectional view of an exemplary processing system 200 in accordance with an embodiment of the present technique. The system 200 may include a processing chamber 205 and a remote plasma system ("RPS") unit 210, which is partially shown. The remote plasma unit 210 may be coupled to the processing chamber 205 with one or more components. The remote 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 a top of the processing chamber 205, and an 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, where the RPS unit 210 installs on the first end 217 of the adapter 215. The adapter 215 may define one or more central channels through portions of the adapter 215. For example, from the first end 217, the central channel 219, i.e., the 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. As described further below, by configuring the adapter 215 such that the first central channel extends more than 50% of the length of the adapter, parasitic plasma formation within the adapter may be limited or prevented.

[0025] The adapter 215 may define a base of a first central channel 219 within the adapter 215, which may define a transition from the central channel 219 to a plurality of apertures 221, which may extend at least partially through the adapter 215. The transition may occur at a location below the midpoint through the adapter, for example, closer to the second end 218 of the adapter 215. For example, the aperture 221 may extend from a base of the first central channel 219 toward the second end 218 of the adapter 215 and may extend into fluid communication 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, may extend 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.

[0026] By limiting the length of the second central channel through the adapter, parasitic plasma formation can be limited within the adapter. Similarly, the aperture 221 can be characterized by a diameter configured to limit 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 that is less than about 50% of the diameter of the central channel 219, and can be characterized by a diameter that is less than about 40%, less than about 30%, less than about 20%, less than about 10%, less than about 5%, or less than the diameter of the central channel 219. The second central channel 223 can be characterized by a cross-sectional diameter similar to the first central channel 219 in some embodiments, but the diameter can be greater than or less than the diameter of the first central channel 219 in some embodiments.

[0027] Depending on the plasma power utilized in the processing system, the aperture 221 may 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. This may limit or prevent plasma generation within the aperture, thereby controlling plasma formation upstream of the mixing manifold 230 in some embodiments. The adapter 215 may also define a ledge, as described further below, on which the system cover or housing 220 may be placed as shown. The housing may be coupled to an electrical ground as shown, and thus the adapter 215 may be coupled to an electrical ground in some embodiments of the present technology.

[0028] The adapter 215 may be made from a ceramic or insulating material, but in some embodiments, the adapter 215 may be made from or include aluminum with oxides of aluminum, 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 effluents from the remote plasma unit 210. The inner surface of the adapter 215 may be anodized with various materials that may be inert to plasma effluents of, for example, fluorine, and 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 may include a ceramic and may operate to electrically isolate the adapter 215 from the mixing manifold 230, which 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 the second central channel 223 of the adapter 215 to an opposite side of the isolator 225. A portion of the central aperture 227 proximate the second central channel 223 may be characterized by a diameter equal to or similar to a diameter of the second central channel 223. The central aperture 227 may be characterized by a taper rate of about 10% or more along the length of the isolator 225, and in embodiments may be characterized by a taper rate of 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.

[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 precursors into the processing chamber 205. The mixing manifold 230 may also be configured to incorporate additional precursors with the mixed precursors supplied from the adapter 215. The mixing manifold 230 may provide a second stage of mixing in the system. The mixing manifold 230 may define ports along an 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 in 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 extending from the first end 232 to a flared portion. The first portion of the central channel 236 may be characterized by a cylindrical profile and may be characterized by a diameter similar to or greater than the outlet of the central aperture 227 of the isolator 225. The flared portion may be characterized by a percentage of flare 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, in embodiments. The mixing manifold 230 may be made from a similar or different material than the adapter 215 in embodiments. For example, the mixing manifold 230 may include nickel, which may provide adequate protection against all precursors that may contact portions of the mixing manifold. Unlike conventional techniques, problems related to recombination may not occur because the fluorine plasma effluent 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 into diatomic fluorine, which may contribute to material loss on the substrate in conventional techniques. When the fluorine effluent is mixed before being delivered to the nickel, nickel plated or coated components, the process may be limited because the concentration of the fluorine effluent is reduced, further protecting the features at the substrate level.

[0032] The chamber 205 may include several components in a stacked arrangement. The chamber stack may include a gas box 240, a blocker plate 250, a face plate 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 set of precursors through the chamber to provide a uniform supply of etchant or other precursor to a substrate 293 for processing. 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 an embodiment, these distribution components may be stacked plates that each at least partially define 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 deliver precursors into the chamber 205. The gas box inlet may be sized to align with the outlet of the mixing manifold 230. For example, the inlet and / or central channel 242 may be characterized by a similar or larger diameter than the outlet of the mixing manifold in embodiments. The central channel 242 may extend through the gas box 240 and be configured to deliver one or more precursors into the interior volume of the processing chamber. The gas box 240 may include or be characterized by a first surface 243, such as a top surface, and a second surface 245 opposite the first surface 243, such as a bottom surface of the gas box 240. A heater or weldment may be coupled to the top surface 243 to define a channel for receiving a cooling fluid for temperature control.

[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 distribution of a precursor, such as an etchant, from a central channel 242 of the gas box and begin distributing the precursor throughout the chamber 205 for uniform delivery to the substrate. The face plate 260 may include a first surface 262 and a second surface 264 opposite the first surface 262. The face plate 260 may be coupled to the gas box 240 at the first surface 262 to engage an outer annular portion of the gas box. The face plate 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 and within which the gas box 240 and central channel 242 may extend.

[0035] The blocker plate may be spaced apart from the faceplate to allow further distribution of the precursors after they are distributed through the blocker plate. In some embodiments, one or more of the components of the gas box, blocker plate, and faceplate may be in direct physical and electrical contact with the mixing manifold. The components may be electrically coupled to a power source, such as an RF power source 255, which may provide power to the components to generate plasma in an area defined between the faceplate and other downstream components. To generate a capacitively coupled plasma between the faceplate and one or more other components, a spacer 265 may be disposed between the faceplate and other components, which may electrically insulate the faceplate from the other components. Therefore, the spacer 265 may be a dielectric component, such as a 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 to the opposite side of the spacer 265. The ion suppression element 270, together with the faceplate 260 and radially defined by the spacer 265, may define a remote plasma region 267 within the processing chamber. This region may be referred to as remote in that the substrate being processed may not be directly exposed to plasma effluents generated in the plasma region 267. In this manner, plasma bombardment of the wafer may be limited or prevented. Additionally, the ion suppression element 270 may be configured to reduce ion migration into the processing region of the chamber 205 housing the substrate. The ion suppression element 270 may define a number of apertures through the structure. A showerhead 280 may be disposed adjacent to the ion suppression element 270, and the ion suppression element may be mounted on the showerhead 280. While any perforated plate or manifold may be included in embodiments of the present technology, in some embodiments the showerhead 280 may be a dual channel showerhead as shown. The showerhead may include two plates joined 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 or the like, may define apertures that provide fluid access from the volume, while the top plate may prevent access upstream from the top plate. The top and bottom plates may also define axially aligned holes to create channels that extend through the showerhead. In this way, the showerhead may allow precursors to be delivered through the showerhead from upstream, and the precursors may not interact with precursors delivered 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 mounted on a lid spacer 285 that may at least partially define a processing region in which a substrate 293 may be disposed for semiconductor processing. The lid spacer 286 may be an insulating or dielectric material in some embodiments, although in embodiments the components may also be conductive. 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 may control the internal plasma formation and confine the formation to a remote plasma region 267 between the faceplate 260, which may be electrically powered, and the ion suppression element 270, which may be grounded. Thus, the system 200 may include both an RPS unit for remote plasma generation and a region inside the chamber where plasma generation may also take place.

[0038] As described above, the mixing manifold 230 may be electrically coupled to the gas box 240 and other components of the powered electrode. However, the adapter 215 may be grounded. In some conventional setups, such a configuration may allow plasma to be generated upstream of the gas box during operation of the powered electrode. This may damage components and may affect plasma formation in the remote plasma region 267, which may reduce etching and processing uniformity on the substrate. Furthermore, the RPS unit may often be operated at a lower frequency than the capacitively coupled plasma power source, which may allow backflowing plasma to enter and damage the RPS unit. For example, while the power source 255 may operate at any number of higher frequencies, such as 13.56 MHz in one non-limiting example, the RPS unit may operate at a lower frequency, such as hundreds of kilohertz or less. In conventional setups that may not include the additional grounding discussed herein, the RPS unit may effectively act as an additional ground path for the powered electrode due to the mismatch in operating frequency. Plasma may then be generated upstream and enter the RPS unit, which may damage components. However, the present technology may limit or prevent these effects by 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 from entering the RPS unit, and the components may be configured to limit or prevent plasma generation.

[0039] 3 illustrates a cross-sectional view of a portion of an exemplary processing system 200 in accordance with some embodiments of the present technology. The view may show additional aspects of previously discussed components and may include any feature, aspect, or characteristic of any of the components described above. As previously discussed, the RPS unit 210 may be installed on a first end of an adapter 215, which may be coupled to an isolator 225 at a second end of the adapter. The adapter 215 may also define a ledge 305 between the first end of the adapter, which may include a mating flange for the RPS unit as shown, and the second end of the adapter, which may include a mating flange for a lower component as discussed below. The ledge 305 may be a recessed ledge from the outer diameter of the adapter and may be spaced apart along the length of the adapter, and will be located along the portion where the first central channel 219 is defined.

[0040] The system housing 220 may be mounted on the ledge 305 as shown and may be coupled to the adapter. As previously described, the system housing may be grounded, which may electrically ground 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 a bolt, which may be installed in a bushing as shown, although it should be understood that any coupler or fastener may be used to maintain physical contact between the components. To maintain symmetry for the 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 with the housing.

[0041] A flange 310 may be defined at a second end of the adapter 215 and may define one or more apertures to allow for coupling with additional components. As shown, the adapter 215 may be coupled to the gas box 240 along with the isolator 225 and the mixing manifold 230. Elastomeric elements or O-rings may be disposed between the components to fluidly seal the components during operation. However, as previously described, the adapter 215 may be grounded, while the mixing manifold 230 and the gas box 240 may be coupled to a power source to operate as powered electrodes for plasma generation. To limit short circuits, in some embodiments of the present technology, the connecting components used to couple the 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 bushings 212 may be seated and recessed as shown in the respective apertures of the adapter 215, which may limit or prevent contact or electrical coupling between the bolt and the grounded adapter. Additionally, the apertures defined through the adapter may be characterized by a diameter that may be at least two or more times the diameter of the mating parts, which may limit electrical shorting between the materials. In some embodiments, the bushings 212 may extend completely through the apertures in the adapter and may be seated at or within the isolator.

[0042] As mentioned above, due to the grounded adapter, plasma generation upstream of the powered mixing manifold may be a challenge in the prior art. However, the present technology may include an adapter configured to limit the generation of plasma within the component. For example, as previously described, the second central channel 223 may extend less than about 50% of the length of the adapter 215, less than about 20% of the length of the adapter, less than about 10% of the length of the adapter, or less in the direction of flow from the RPS unit, thereby controlling the available space for plasma generation. For example, the length of the second portion may 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, or less than about 8 mm. It may be maintained at 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, in which case the chamber may be operated at a pressure of tens of Torr or less.

[0043] When the prior art utilizes an adapter with increased distance to the components in this electrical configuration, the region may result in a hollow cathode effect, which may increase the current density in that area. This may result in increased ionization that may advance plasma generation in the components. The present technology may limit the distance to any of the ranges listed above, which may limit or prevent plasma generation during operation of the functioning capacitively coupled electrodes. By reducing the spacing, the mean free path length may be controlled prior to impact with the transition, which may prevent ionization in the components. Similarly, the aperture 221 defined at the transition between the first central channel 219 and the second central channel 223 may be sized to prevent hollow cathode effects, and in some embodiments of the present technology may be sized to any of the ranges listed above, such as 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.

[0044] The central aperture 227 of the isolator 225 may also affect the likelihood of plasma generation in the space defined by the central aperture, which may create a volume between the electrically powered mixing manifold and the grounded adapter. Therefore, depending on the power being supplied and the pressure at which the chamber may operate, in some embodiments, the central aperture 227 may be altered to multiple apertures. FIG. 4 illustrates a cross-sectional view of a portion of an exemplary processing system 200 in accordance with some embodiments of the present technique. The figure may illustrate additional aspects of the components previously discussed and may include any feature, aspect, or characteristic of any of the components described above. The figure may illustrate additional isolator configurations in accordance with some embodiments of the present technique.

[0045] The isolator 405 may include any feature, aspect, or characteristic of the isolator 225, as discussed above, and may include multiple channels 410 instead of a central aperture as previously described. Because the insulating isolator defines the space between the capacitively coupled electrodes, plasma generation may develop in the volume defined by the isolator. The diameter of the single centrally defined aperture may be shortened in some embodiments, but depending on the chamber operating parameters such as pressure and plasma electrode power, plasma generation may not be prevented while maintaining adequate flow through the components. By including multiple channels 410, sufficient flow through the isolator may be maintained and plasma generation may be prevented. For example, the apertures may be maintained at any of the diameters described above relative to the aperture 221 defined at the transition in the adapter. Additionally, as shown, the channel 410 may be laterally offset from the central axis through any aperture 221 at the transition in the adapter. Thus, 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 before collision, which may prevent plasma generation between the mixing manifold and the adapter. By utilizing components and configurations according to embodiments of the present technology, RPS units and capacitively coupled plasmas may be utilized to improve operational flexibility over conventional systems.

[0046] 5 illustrates steps of a method 500 for performing processes in a system according to some embodiments of the present technique. Method 500 may be performed in system 200 and may allow for improved process flexibility while protecting components from etchant damage and limiting upstream plasma generation during capacitively coupled plasma formation. Method 500 may include several steps of plasma processing and may describe steps that may be performed in an exemplary system, although the steps may be performed in any number of processes in different orders. Although an etching process is described, it should be understood that the process may include cleaning or deposition steps as well.

[0047] Method 500 may include forming a plasma in the RPS unit at optional step 505. At step 510, the plasma effluent may flow into a processing chamber. The plasma effluent 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 to mix with the plasma effluent, such as through a mixing manifold. At optional step 515, the plasma effluent and materials may flow through the chamber to perform a process on a substrate disposed within the chamber or within a processing region of the chamber.

[0048] The method 500 may also include forming a plasma in the processing chamber at step 520, such as between a faceplate and an ion suppression element, as previously described. In some embodiments, the plasma may be contained in a remote plasma region defined in the processing chamber, and the plasma may be limited or prevented from forming upstream from the remote region, such as in an isolator or adapter, as previously described. In optional step 525, the plasma effluent may flow into the processing region and impinge on the processing chamber or a substrate disposed within the processing region. Improved plasma uniformity and processing accuracy may be provided by utilizing components and chamber configurations as previously described.

[0049] In the above description, for purposes of explanation, numerous details are set forth in order to provide an understanding of various embodiments of the present technology. However, it will be apparent to one skilled in the art that certain embodiments may be practiced without some of these 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. Moreover, some well-known processes and elements have not been described to avoid unnecessarily obscuring the technology. Therefore, the above description should not be taken as limiting the scope of the technology.

[0051] Where a range of values ​​is given, it is understood that each intervening value between the upper and lower limits of that range is also specifically disclosed, to the smallest fraction of the unit of the lower limit, unless the context clearly indicates otherwise. Any narrower range between any stated or unstated intervening value in a stated range and any other stated or intervening value in that stated range is encompassed. The upper and lower limits of these smaller ranges may be independently included or excluded within the range, and each range in which either one or both of the upper and lower limits are included, or both are included, within this smaller range, subject to any specifically excluded upper or lower limit in the stated range, is also encompassed within the technology. Where a stated range includes one or both of the upper and lower limits, ranges excluding either or both of these 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 thereof" includes reference to one or more precursors and equivalents thereof known to those skilled in the art, and so forth.

[0053] Also, as used in this specification and the claims that follow, the words "comprise," "comprising," "contain," "containing," "include," and "including" are intended to specify the presence of stated features, integers, components, or steps, but do not exclude the presence or addition of one or more other features, integers, components, steps, operations, 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. 10. 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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