Processing system and method for improving the productivity of void-free and seam-free tungsten gap-filling processes.

Abstract

FIELD OF THE DISCLOSURE [0002] Embodiments herein relate generally to electronic device manufacturing, and more particularly to systems and methods for forming substantially void-free and seam-free tungsten features in semiconductor device manufacturing processes. In one embodiment, a substrate processing system features a processing chamber and a gas supply system fluidly coupled to the processing chamber. The gas supply system includes a first radical generator for use in a differentially inhibited processing process and a second radical generator for use in a chamber cleaning process. The processing system is configured to periodically condition the first radical generator by forming a plasma of a relatively small amount of a halogen-based gas.

Description

Technical Field

[0001] Embodiments of the present specification relate to systems and methods used in the manufacture of electronic devices, and more particularly, to systems and methods used to form tungsten features in semiconductor devices.

Background Art

[0002] Tungsten (W) is widely used in the manufacture of integrated circuit (IC) devices to form conductive features that require relatively low electrical resistance and relatively high resistance to electromigration. For example, tungsten can be used as a metal filling material to form source contacts, drain contacts, metal gate fills, gate contacts, interconnects (e.g., horizontal features formed on the surface of a dielectric material layer), and vias (e.g., vertical features formed through a dielectric material layer to connect other interconnect features disposed above and below the dielectric material layer). Due to its relatively low resistivity, tungsten is also commonly used to form bit lines and word lines used to address individual memory cells within a memory cell array of a dynamic random access memory (DRAM) device.

[0003] As circuit density increases and device features continue to shrink to meet the requirements of next-generation semiconductor devices, it is becoming increasingly difficult to reliably create tungsten features. Problems such as voids and seams formed during conventional tungsten deposition processes are exacerbated as feature sizes decrease, which can negatively impact device performance and reliability or even render the device inoperable.

[0004] Therefore, what is needed in the art is a processing system and method that solves the above problems.

Summary of the Invention

[0005] The embodiments described herein generally relate to the manufacturing of electronic devices, and more particularly to systems and methods for forming substantially void-free and seam-free tungsten features in semiconductor device manufacturing processes. In some embodiments, the systems and methods described herein provide a single-chamber processing solution that reduces substrate processing variability and improves substrate processing throughput, thereby facilitating the reliable integration of seam-free tungsten gap-filling into high-volume production lines.

[0006] In one embodiment, the substrate processing system includes a processing chamber comprising a chamber lid assembly, one or more chamber sidewalls, and a chamber base that collectively define a processing volume. The processing system further includes a gas supply system fluidly coupled to the processing chamber, comprising a first radical generator and a second radical generator, and a non-temporary computer-readable medium storing instructions for performing a method of processing multiple substrates when executed by a processor. This method includes (a) receiving a substrate into a processing volume section; (b) exposing the substrate to an activation gas, wherein the activation gas contains emissions of the processing plasma formed in a first radical generator; (c) exposing the substrate to a first tungsten-containing precursor and a first reducing agent to deposit a tungsten gap-filling material; (d) transferring the substrate out of the processing volume section; (e) adjusting the first radical generator before or after (a); and (f) repeating (a) to (e) if the number of continuously processed substrates is below a threshold. Adjusting the first radical generator includes (i) flowing an adjustment gas into the first radical generator, wherein the adjustment gas contains halogen components; and (ii) igniting the adjustment plasma of the adjustment gas and maintaining it for a first period of time.

[0007] In one embodiment, a method for processing a substrate includes (a) receiving the substrate into a processing volume section of a processing system; (b) exposing the substrate to an activation processing gas; (c) exposing the substrate to a first tungsten-containing precursor and a first reducing agent; (d) transferring the substrate out of the processing volume section; (e) adjusting a first radical generator before or after (a); and (f) repeating (a) to (e) if the number of substrates processed consecutively is below a threshold. In one embodiment, a processing system used to carry out this method includes a processing chamber comprising a chamber lid assembly, one or more chamber sidewalls, and a chamber base that collectively define a processing volume section, and a gas supply system fluidically coupled to the processing chamber, comprising a first radical generator and a second radical generator. In one embodiment, preparing the first radical generator includes (i) flowing a conditioning gas through the first radical generator, wherein the conditioning gas contains halogen components, and (ii) igniting the conditioning plasma of the conditioning gas and maintaining it for a first period of time. In some embodiments, the activated treatment gas includes the emissions of the treatment plasma formed in the first radical generator.

[0008] To allow for a more detailed understanding of the features enumerated above in this disclosure, a more detailed description of the disclosure, which has been briefly summarized above, can be given with reference to embodiments, some of which are shown in the accompanying drawings. However, it should be noted that the accompanying drawings show only exemplary embodiments and should therefore not be considered limiting in scope, as other equally effective embodiments may be permitted. [Brief explanation of the drawing]

[0009] [Figure 1A-1B] This is a schematic cross-sectional view of a portion of a substrate showing undesirable void or seam formation in the tungsten feature area formed in a conventional manner. [Figure 2A] This is a schematic side view of a processing system that can be used to carry out the method described herein, according to one embodiment. [Figure 2B] This is a close-up cross-sectional view of a part of the processing system shown in Figure 2A, according to one embodiment. [Figure 3] This figure shows a substrate processing method according to one embodiment, which can be performed using the processing system shown in Figures 2A and 2B. [Figure 4A-4D] Figure 3 is a schematic cross-sectional view of a part of a substrate showing various embodiments of the method described therein. [Figure 5] This figure shows a substrate processing method according to another embodiment, which can be performed using the processing system shown in Figures 2A to 2B. [Figures 6A-6D] Figure 5 is a schematic cross-sectional view of a part of a substrate showing various embodiments of the method described therein. [Figures 7A-7B] This graph shows the in-substrate and inter-substrate treatment results of film layers formed using the method described herein. [Figure 8] This is a schematic plan view of an exemplary multi-chamber processing system that can be used to perform the method described herein, according to one embodiment. [Modes for carrying out the invention]

[0010] For ease of understanding, the same reference numerals are used, where possible, to designate identical elements common to the figures. Elements and features of one embodiment are intended to be usefully incorporated into other embodiments without further detail.

[0011] Embodiments of this specification generally relate to the manufacture of electronic devices, and more particularly to systems and methods for forming substantially void-free and seam-free tungsten features in semiconductor device manufacturing processes.

[0012] Generally, tungsten features in IC devices are formed using a damascene (metal inlay) manufacturing process flow. The damascene process flow begins by depositing a layer of dielectric material on the surface of a substrate, patterning the dielectric layer to form multiple openings, and then depositing a layer of tungsten material on the surface of the dielectric layer to fill the openings. Often, a layer of barrier or adhesive material, such as titanium nitride (TiN), is deposited to line the openings before the tungsten layer is deposited. The deposition of the barrier and tungsten layers creates an overburden of barrier and tungsten material on the substrate field, which is then removed using a chemical mechanical polishing (CMP) process.

[0013] The CMP process uses a combination of chemical and mechanical activity provided at least partially by the abrasive fluid to flatten tungsten overbaden from the field. A typical tungsten CMP abrasive fluid comprises an aqueous solution containing one or more chemically active components and suspended abrasive components, such as nanoparticles, to form an abrasive slurry. The chemically active components soften the tungsten surface, for example, by oxidizing the surface to form a thin layer of tungsten oxide, and the abrasive components polish (remove) the tungsten oxide to expose the tungsten underneath. polishing This cycle continues throughout the CMP process until the tungsten overburden is removed from the field of the dielectric layer, leaving behind the embedded tungsten features.

[0014] Generally, tungsten deposited using conventional methods is highly conformal to the underlying patterned surface. Unfortunately, as device feature areas become smaller and aspect ratios increase, the formation of undesirable voids and seams in tungsten feature areas formed using conformal tungsten deposition methods becomes almost unavoidable. The resulting undesirable voids and seams, such as those shown in Figures 1A and 1B, can cause problems with device performance and reliability, or even lead to device failure.

[0015] Figure 1A is a schematic cross-sectional view of a substrate 10A showing an undesirable void 20 formed during a conventional tungsten deposition process. Here, the substrate 10A includes a patterned surface 11 which comprises a dielectric layer 12 (shown filled with a portion of the tungsten layer 15) having a high aspect ratio opening formed therein, a barrier material layer 14 deposited on the dielectric layer 12 to line the opening, and a tungsten layer 15 deposited on the barrier material layer 14. The tungsten layer 15 is formed using a conventional deposition process, such as a chemical vapor deposition (CVD) process or an atomic layer deposition (ALD) process, and the tungsten is conformally deposited (grown) on the patterned surface 11 to fill the opening. The tungsten layer 15 forms a tungsten feature portion 15A within the opening and an overburden of material on the field of the patterned surface 11 (tungsten overburden layer 15B).

[0016] In Figure 1A, the opening has a non-uniform profile, being narrower on the surface of the substrate 10A and widening (bending outwards in an arc) as the opening extends inward from the surface into the dielectric layer 12. As shown, the overhang portion of the conformal tungsten layer 15 grows together to obstruct or "pinch off" the entrance to the opening before the opening is completely filled, thereby causing undesirable voids 20 within the tungsten feature area 15A, i.e., a lack of tungsten material. If the voids 20 are opened (exposed) during the subsequent CMP process, polishing fluid may penetrate the tungsten feature area 15A, and the chemically active components of the polishing fluid may cause further loss of tungsten material within the tungsten feature area 15A, e.g., undesirable feature area coring (key-holing) by corrosion and / or static etching of the tungsten material. This undesirable tungsten loss may result in device performance and reliability problems, or ultimately, complete device failure. Even without void formation, undesirable seam formation in tungsten features, such as those shown in Figure 1B, is almost unavoidable when using conventional tungsten deposition processes.

[0017] Figure 1B is a schematic cross-sectional view of substrate 10B showing an undesirable seam 24 formed during a conventional tungsten deposition process. Here, the patterned surface 11 includes an opening (filled with a portion of the tungsten layer 15) having a substantially uniform profile as the opening extends from the surface of substrate 10B into the dielectric layer 12. The opening is filled with tungsten and no voids are formed. Nevertheless, conformal growth of the tungsten layer 15 outward from the walls of the opening results in an undesirable seam 24 extending through the center of the tungsten feature portion 15A formed in the opening. As shown in the void 20 in Figure 1A, the seam 24 is susceptible to corrosion from the chemically active components of the tungsten polishing solution, which can lead to undesirable loss of tungsten material from the feature portion 15A if the seam 24 is exposed during the CMP process.

[0018] Fortunately, early techniques enabling selective tungsten deposition, and thereby bottom-up tungsten gap filling, have shown promise in forming virtually void-free and seam-free feature areas desirable for next-generation devices. Generally, bottom-up tungsten gap filling process schemes use substrate processing and tungsten deposition processes that are highly sensitive even to slight changes in substrate processing conditions. This process sensitivity non-uniformly affects the selectivity of tungsten deposition across the substrate surface and / or causes undesirable processing variability between multiple substrates processed over time within the same system, or between substrates processed in different systems. Furthermore, due to (at least partially) the high process sensitivity to any change in process conditions, different parts of the selective tungsten gap filling process are often carried out in different specialized and dedicated processing chambers, and the substrates to be processed are transferred between them one or more times.

[0019] Unfortunately, the specialized processing systems and substrate handling requirements for selective tungsten gap filling undesirably increase the time and cost of forming tungsten features compared to conventional tungsten deposition processes. Therefore, embodiments herein provide processing systems configured to perform combinations of individual embodiments of this method without transferring substrates between processing chambers, thereby improving the overall substrate processing throughput and capabilities of the tungsten gap filling processing scheme described herein.

[0020] Generally, a gap filling process method includes forming a differential tungsten deposition suppression profile in an opening of a feature formed on a surface of a substrate, filling the opening with a tungsten material according to the suppression profile, and depositing a tungsten overburden on a field surface of the substrate. Forming the tungsten deposition suppression profile generally includes forming a tungsten nucleation layer and treating the tungsten nucleation layer using an activated nitrogen species, such as a processing radical. The nitrogen processing radical is incorporated into a part of the nucleation layer, for example, by adsorption of nitrogen species and / or by reaction with metallic tungsten of the nucleation layer, to form tungsten nitride (WN). The adsorbed nitrogen and / or nitrided surface of the tungsten nucleation layer preferably delays (suppresses) tungsten nucleation, thereby delaying (suppressing) subsequent tungsten deposition thereon.

[0021] In some embodiments, the processing radical is formed remotely from the substrate processing chamber by using a remote plasma source fluidly coupled to the substrate processing chamber. The desired suppression effect on the field of the patterned surface and the desired suppression profile of the opening formed in the patterned surface are achieved by controlling processing conditions in the processing chamber, such as temperature and pressure, and by controlling the concentration, flux, and energy of the processing radical on the substrate surface. Generally, the processing radical is formed from a non-halogen nitrogen-containing gas such as N2, NH3, NH4, or a combination thereof.

[0022] The tungsten nucleation and deposition process of the gap filling process method generally includes flowing a tungsten-containing precursor and a reducing agent into the processing chamber and exposing the substrate surface thereto. The tungsten-containing precursor and the reducing agent react on the surface of the substrate in one of a chemical vapor deposition (CVD) process, a pulsed CVD process, an atomic layer deposition (ALD) process, or a combination thereof to deposit a tungsten material thereon.

[0023] Inevitably, tungsten and tungsten-related radionuclides (undesirable tungsten residues) accumulate on the surface of the processing chamber as well as the substrate surface. If not removed, the tungsten residues can cause defects (particles) that, if transferred to the substrate surface, may lead to device failure. Therefore, the processing system described herein is configured to periodically perform a chamber cleaning step in which undesirable tungsten residues are removed from the internal surface of the processing chamber using cleaning chemistry. Herein, the cleaning chemistry includes activated halogen radionuclides, such as fluorine or chlorine (cleaning) radicals, which are formed remotely from the processing chamber.

[0024] The chamber cleaning process generally includes flowing halogen cleaning radicals into the processing chamber, reacting the cleaning radicals with tungsten residue to form volatile tungsten radionuclides, and exhausting the volatile tungsten radionuclides from the processing chamber through an exhaust valve. The chamber cleaning process is generally performed between substrate processing, i.e., after the processed substrates have been removed from the processing chamber and before the processed substrates to be subsequently processed are received into the processing chamber.

[0025] In some embodiments, cleaning radicals are formed from a halogenated cleaning gas such as NF3 using a remote plasma source fluidically coupled to the processing chamber. By forming the cleaning radicals remotely from the processing chamber, ion-based damage to chamber components is preferably avoided, such as corrosion of surfaces within the processing chamber that would normally occur if cleaning radicals were formed within the processing chamber by using in-vitro plasma. Thus, ion-based damage is preferably contained on the plasma-facing surface within the remote plasma source, which may feature a halogenated plasma-resistant liner or coating to protect the underlying material from the corrosive effects of the halogenated plasma.

[0026] In some embodiments, the remote plasma source used to form the treatment radicals used in the suppression process is also used to form the cleaning radicals used in the chamber cleaning process. Unfortunately, when the same remote plasma source is used to supply radicals to both the suppression process and the chamber cleaning process, undesirable process variations in the resulting suppression profile have been observed. Undesirable process variations include variations in the suppression profile between substrates and / or non-uniform treatment results across the substrate surface.

[0027] While not bound by theory, it is believed that at least some undesirable processing variations result from damage to surfaces within the remote plasma source caused by halogen-based cleaning plasmas. Further, it is conceivable that at least some processing variations are caused by nitrogen adsorption and / or nitridation of surfaces within the remote plasma source due to exposure to nitrogen-based processing plasmas. For example, halogen ion-based damage and / or accumulation of halogen-based contaminants on the plasma-facing surface of the remote plasma source may adversely affect the dissociation and recombination rates of nitrogen-based processing radicals subsequently formed within the remote plasma source. Variations in the dissociation and recombination rates of processing radicals formed using a remote cleaning plasma source can lead to variations in the concentration, flux, and energy of activated nitrogen nuclides on the substrate surface, resulting in unstable processing outcomes. Therefore, the processing systems provided herein comprise at least two remote plasma sources, with a first remote plasma source dedicated to and / or exclusively for the generation of processing radicals, and a second remote plasma source dedicated to and / or exclusively for the generation of cleaning radicals during the chamber cleaning process.

[0028] As discussed below, by using plasma sources dedicated to each suppression process and chamber cleaning process, the processing stability of the suppression process is improved compared to a processing system that uses a common plasma source for both. Thus, embodiments herein beneficially provide a relatively low-cost and high-throughput single-chamber solution for seam suppression tungsten gap filling, such as the processing systems shown in Figures 2A-2B.

[0029] Figures 2A and 2B schematically show a processing system 200 that can be used to carry out the bottom-up tungsten gap-filling substrate processing method described herein. Here, the processing system is configured to provide different processing conditions desirable for each of the nucleation process, suppression process, selective gap-filling process, and over-baden deposition process, within a single processing chamber 202, i.e., without transferring the substrate between multiple processing chambers.

[0030] As shown in Figure 2A, the processing system 200 includes a processing chamber 202, a gas supply system 204 fluidly coupled to the processing chamber 202, and a system controller 208. The processing chamber 202 (shown in cross-section in Figure 2A) includes a chamber lid assembly 210, one or more side walls 212, and a chamber base 214, which together define a processing volume 215. The processing volume 215 is fluidly coupled to an exhaust unit 217, such as one or more vacuum pumps, used to maintain the processing volume 215 under near-atmospheric pressure conditions and to discharge the processing gas and processing by-products therefrom.

[0031] The chamber lid assembly 210 includes a lid plate 216 and a shower head 218 coupled to the lid plate 216, which together define a gas distribution volume 219. Here, the lid plate 216 is maintained at a desired temperature using one or more heaters 229 thermally coupled to it. The shower head 218 faces a substrate support assembly 220 located in the processing volume 215. As will be discussed below, the substrate support assembly 220 is configured to move a substrate support 222, and therefore a substrate 230 placed on the substrate support 222, between a raised substrate processing position (as shown) and a lowered substrate transfer position (not shown). When the substrate support assembly 220 is in the raised substrate processing position, the shower head 218 and the substrate support 222 define a processing area 221.

[0032] Here, the gas supply system 204 is fluidly coupled to the processing chamber 202 via a gas inlet 223 (Figure 2B) positioned through the lid plate 216. The processing gas or cleaning gas supplied by using the gas supply system 204 flows through the gas inlet 223 into the gas distribution volume 219 and is distributed to the processing area 221 through multiple openings 232 (Figure 2B) of the shower head 218. In some embodiments, the chamber lid assembly 210 further includes a perforated blocker plate 225 positioned between the gas inlet 223 and the shower head 218. In these embodiments, the gas flowing into the gas distribution volume 219 is first diffused by the blocker plate 225 and then, combined with the shower head 218, supplies a more uniform or desiredly distributed gas flow into the processing area 221.

[0033] Here, the processing gas and processing by-products are discharged radially outward from the processing region 221 through an annular channel 226 surrounding the processing region 221. The annular channel 226 may be formed in a first annular liner 227 positioned radially inward of one or more sidewalls 212 (as shown in the figure), or it may be formed in one or more sidewalls 212. In some embodiments, the processing chamber 202 includes one or more second liners 228, which are used to protect the inner surface of one or more sidewalls 212 or the chamber base 214 from corrosive gases and / or undesirable material deposits.

[0034] In some embodiments, a purge gas source 237, fluidly connected to the processing volume 215, is used to flow a chemically inert purge gas, such as argon (Ar), into a region located directly beneath the substrate support 222, for example, through an opening in the chamber base 214 surrounding the support shaft 262. The purge gas can be used to create a region of positive pressure (compared to the pressure in the processing area 221) beneath the substrate support 222 during substrate processing. Generally, the purge gas flows through the chamber base 214 and upward from there, around the edges of the substrate support 222, and is discharged from the processing volume 215 through annular channels 226. The purge gas reduces unwanted material deposition on the surface directly beneath the substrate support 222 by reducing and / or preventing the flow of material precursor gases to that area.

[0035] Here, the substrate support assembly 220 includes a movable support shaft 262 that extends in a sealed manner through the chamber base 214, such as being surrounded by a bellows 265 in the region below the chamber base 214, and a substrate support 222 positioned on the movable support shaft 262. To facilitate the transfer of the substrate to and from the substrate support 222, the substrate support assembly 220 includes a lift pin assembly 266, which includes a plurality of lift pins 267 coupled to or engaged with a lift pin hoop 268. The plurality of lift pins 267 are movably positioned at an opening formed through the substrate support 222. When the substrate support 222 is positioned in a lowered substrate transfer position (not shown), the plurality of lift pins 267 extend above the substrate receiving surface of the substrate support 222, lifting the substrate 230 from there, allowing the back (inactive) surface of the substrate 230 to be accessed by a substrate handler (not shown). When the substrate support 222 is in the raised or processing position (as shown in the figure), the multiple lift pins 267 retract directly below the substrate receiving surface of the substrate support 222, allowing the substrate 230 to be placed on it.

[0036] Here, the substrate 230 is transferred to and from the substrate support 222 through a door 271, for example, a slit valve, located in one of the one or more side walls 212. Here, one or more openings in the area surrounding the door 271, for example, an opening in the door housing, are fluidly coupled to a purge gas source 237, for example, an Ar gas source. The purge gas is used to prevent the processing gas and cleaning gas from coming into contact with the seal surrounding the door and / or degrading the seal surrounding the door, thereby extending the service life of the door.

[0037] Here, the substrate support 222 is configured for use as a vacuum chuck, in which the substrate 230 is fixed to the substrate support 222 by applying a vacuum to the interface between the substrate 230 and the substrate receiving surface. The vacuum is applied using a vacuum source 272 that is fluidly coupled to one or more channels or ports formed in the substrate receiving surface of the substrate support 222. In other embodiments, for example, if the processing chamber 202 is configured for direct plasma processing, the substrate support 222 may be configured for use as an electrostatic chuck. In some embodiments, the substrate support 222 includes one or more electrodes (not shown) coupled to a bias voltage power supply (not shown), such as a continuous-wave (CW) RF power supply or a pulsed RF power supply, which supplies a bias voltage to it.

[0038] As shown in the figure, the substrate support assembly 220 features a dual-zone temperature control system for independent temperature control in different regions of the substrate support 222. The different temperature control regions of the substrate support 222 correspond to different regions of the substrate 230 placed thereon. Here, the temperature control system includes a first heater 263 and a second heater 264. The first heater 263 is located in the central region of the substrate support 222, and the second heater 264 is located radially outward from the central region so as to surround the first heater 263. In other embodiments, the substrate support 222 may have a single heater or three or more heaters.

[0039] In some embodiments, the substrate support assembly 220 further includes an annular shadow ring 235 used to prevent undesirable material deposition on the circumferential bevel edge of the substrate 230. During substrate transfer to and from the substrate support 222, i.e., when the substrate support assembly 220 is in a lowered position (not shown), the shadow ring 235 rests on an annular ledge in the processing volume 215. When the substrate support assembly 220 is raised or placed in a processing position, the radially outer surface of the substrate support 222 engages with the annular shadow ring 235 such that the shadow ring 235 surrounds the substrate 230 placed on the substrate support 222. Here, the shadow ring 235 is shaped such that when the substrate support assembly 220 is in the raised substrate processing position, the radially inward-facing portion of the shadow ring 235 is positioned over the bevel edge of the substrate 230.

[0040] In some embodiments, the substrate support assembly 220 further includes an annular purge ring 236 positioned on the substrate support 222 so as to surround the substrate 230. In those embodiments, a shadow ring 235 may be positioned on the purge ring 236 when the substrate support assembly 220 is in the raised substrate processing position. Generally, the purge ring 236 features a plurality of radially inward-facing openings fluidly connected to a purge gas source 237. During substrate processing, the purge gas flows into an annular region defined by the shadow ring 235, the purge ring 236, the substrate support 222, and the bevel edge of the substrate 230, preventing the processing gas from entering the annular region and causing undesirable material deposition on the bevel edge of the substrate 230.

[0041] In some embodiments, the processing chamber 202 is configured for direct plasma processing. In those embodiments, the showerhead 218 is electrically coupled to a first power supply 231, such as an RF power supply, which supplies power to ignite and maintain the plasma of the processing gas flowing into the processing area 221 via capacitive coupling with the processing gas. In some embodiments, the processing chamber 202 includes an inductive plasma generator (not shown), the plasma being formed by inductively coupling RF power to the processing gas.

[0042] Here, the processing system 200 is advantageously configured to perform each of the tungsten nucleation, suppression, and bulk tungsten deposition processes of the void-free and seam-free tungsten gap-filling process scheme without removing the substrate 230 from the processing chamber 202. The gas used to perform each of the gap-filling processes and to clean residues from the internal surface of the processing chamber is supplied to the processing chamber 202 using a gas supply system 204 which is fluidly coupled to it.

[0043] Generally, the gas supply system 204 includes one or more remote plasma sources, hereby first and second radical generators 206A-206B, a deposition gas source 240, and a conduit system 294 (e.g., multiple conduits 294A-294F) that fluidly connects the radical generators 206A-206B and the deposition gas source 240 to the lid assembly 210. The gas supply system 204 further includes a plurality of isolation valves, hereby first and second valves 290A-290B, respectively, positioned between the radical generators 206A-206B and the lid plate 216, which can be used to fluidly separate each of the radical generators 206A-206B from the processing chamber 202 and from each other.

[0044] Here, each of the radical generators 206A to 26B features a chamber body 280 defining the respective first and second plasma chamber volume sections 281A to 281B (Figure 2B). Each of the radical generators 206A to 206B is coupled to the respective power supplies 293A to 293B. The power supplies 293A to 293B are used to ignite and maintain the plasma 282A to 282B of the gas supplied to the plasma chamber volume sections 281A to 281B from the corresponding first gas source 287A or second gas source 287B, which is fluidically coupled to the plasma chamber volume sections 281A to 281B. In some embodiments, the first radical generator 206A generates radicals used in the differential suppression process of activity 303 (Figure 3). For example, the first radical generator 206A can be used to ignite and maintain a processing plasma 282A from a non-halogen-containing mixed gas supplied from a first gas source 287A to the first plasma chamber volume section 281A. The second radical generator 206B can be used to generate cleaning radicals used in a chamber cleaning process, such as activity 308 (Figure 3), by igniting and maintaining a cleaning plasma 282B from a halogen-containing mixed gas supplied from a second gas source 287B to the second plasma chamber volume section 281B.

[0045] Generally, nitrogen-treated radicals have a relatively short lifetime (compared to halogen-cleaning radicals) and may be relatively sensitive to recombination from collisions with other nuclides in the surface and / or treatment plasma ejecta within the gas supply system 204. Therefore, in embodiments of this specification, the first radical generator 206A is generally positioned closer to the gas inlet 223 than the second radical generator 206B, for example, to provide a relatively short travel distance from the first plasma chamber volume section 281A to the treatment area 221.

[0046] In some embodiments, the first radical generator 206A is also fluidly coupled to a second gas source 287B, which supplies a halogen-containing conditioning gas to the first plasma chamber volume section 281A for use in a plasma source condition process, such as that described in activity 309 of Method 300. In those embodiments, the gas supply system 204 may further include a plurality of diverter valves 291 that are operable to guide the halogen-containing mixed gas from the second gas source 287B to the first plasma chamber volume section 281A.

[0047] Suitable remote plasma sources that can be used with one or both of the radical generators 206A-206B include radio frequency (RF) or very high frequency (VHRF) capacitively coupled plasma (CCP) sources, inductively coupled plasma (ICP) sources, microwave-inductive (MW) plasma sources, electron cyclotron resonance (ECR) chambers, or high-density plasma (HDP) chambers.

[0048] As shown in the figure, the first radical generator 206A is fluidically coupled to the processing chamber 202 by using first and second conduits 294A-294B that extend upward from the gas inlet 223 and connect to the outlet of the first plasma chamber volume section 281A. A first valve 290A, positioned between the first conduit 294A and the second conduit 294B, is used to selectively fluidically isolate the first radical generator 206A from the processing chamber 202 and the rest of the gas supply system 204. Generally, the first valve 290A is closed during the chamber cleaning process (activity 308) to prevent the activation cleaning gas, such as halogen radicals, from flowing into the first plasma chamber volume section 281A and damaging its surface.

[0049] Here, the first radical generator 206A, the first and second conduits 294A-294B, and the first valve 290A are arranged and / or configured such that the processing plasma 282A is not in a direct line of sight to the gas inlet 223, for example by having bends in one or both of the conduits 294A-294B. In other embodiments, the first plasma chamber volume section 281A may be aligned with the gas inlet 223 so as to have a direct line of sight from the processing plasma 282A through the gas inlet 223 into the processing chamber 202. A direct line of sight can beneficially reduce undesirable recombination of processing radicals by reducing gas-phase collisions between processing radicals.

[0050] The second radical generator 206B is fluidically coupled to the second conduit 294B and therefore to the processing chamber 202 by using the third and fourth conduits 294C-294D. Here, the second radical generator 206B is selectively isolated from the processing chamber 202 and the rest of the gas supply system 204 by using a second valve 290B located between the third conduit 294C and the fourth conduit 294D. As shown in the figure, the second radical generator 206B, the third and fourth conduits 294C-294D, and the second valve 290B are arranged so that the cleaning plasma 282B is not in a direct line of sight to the second valve 290B or the processing chamber 202. By blocking the direct line of sight between the cleaning plasma 282B, the second valve 290B, and the processing chamber 202, halogen ion-induced damage to the components of the second valve 290B and the processing chamber 202 is prevented, thereby preferably extending their service life.

[0051] In some embodiments, one or both of the plasma-facing surfaces 283 of the plasma chamber volumes 281A-281B are formed of a halogen-based plasma-resistant material such as aluminum oxide, aluminum nitride, silicon oxide, fused silica, quartz, sapphire, or a combination thereof. In some embodiments, the plasma-facing surfaces 283 of the plasma chamber volumes 281A-281B include a tube or liner formed of a halogen-based plasma-resistant material. In other embodiments, the plasma-facing surface 283 is characterized by a coating or layer of a halogen-based plasma-resistant material formed on the interior portion of the chamber body 280, such as an anodized aluminum layer formed on the interior portion of the aluminum chamber body. In some embodiments, one or more of the conduits 294A-294F are lined with a low-recombination dielectric material 292 such as fused silica, quartz, or sapphire, thereby reducing the recombination of the activated nuclide when the activated nuclide in the remote plasma emitter is supplied to the processing chamber 202.

[0052] Here, the sediment gas, e.g., tungsten-containing precursor and reducing agent, is supplied from the sediment gas source 240 to the processing chamber 202 using a fifth conduit 294E. As shown in the figure, the fifth conduit 294E is coupled to the second conduit 294B adjacent to the gas inlet 223, and as a result, the first and second valves 290A-290B can be used to separate the first and second radical generators 206A-206B from the sediment gas introduced into the processing chamber 202, respectively. In some embodiments, the gas supply system 204 further includes a sixth conduit 294F coupled to the fourth conduit 294D adjacent to the second valve 290B. The sixth conduit 294F is fluidly coupled to a bypass gas source 238, e.g., an argon (Ar) gas source, and can be used to periodically purge a portion of the gas supply system 204 with respect to undesirable residues, suppression, and / or sediment gas.

[0053] The operation of the processing system 200 is facilitated by a system controller 208. The system controller 208 includes a programmable central processing unit, here a CPU 295, which is operable by memory 296 (e.g., non-volatile memory) and support circuitry 297. The CPU 295 is one of any form of general-purpose computer processor used in industrial environments, such as a logic control unit (PLC) that can be programmed to control various chamber components and subprocessors. Memory 296 coupled to the CPU 295 facilitates the operation of the processing chambers. Support circuitry 297 conventionally includes caches, clock circuits, input / output subsystems, power supplies, etc., and combinations thereof, coupled to the CPU 295 and various components of the processing system 200 (or the multi-chamber processing system 800 in Figure 8) to facilitate control of board processing operations.

[0054] Here, the instructions in memory 296 are in the form of a program product, such as a program that implements the method of the present disclosure. In one example, the present disclosure may be implemented as a program product stored on a computer-readable storage medium for use in a computer system. The program of the program product defines the function of the embodiment (including the method of the present specification). Thus, a computer-readable storage medium is an embodiment of the present disclosure if it holds computer-readable instructions that direct the function of the method of the present specification.

[0055] Advantageously, the processing system 200 described above can be used to carry out each of the nucleation, suppression, gap-filling deposition, and overbaden deposition processes of the method 300 described in Figure 3, thereby providing a single-chamber seam-free tungsten gap-filling solution.

[0056] Figure 3 shows a method 300 for processing a substrate according to one embodiment, which can be performed using the processing system 200. Figures 4A to 4D are schematic cross-sectional views of a portion of the substrate 400 showing aspects of method 300 at different stages of the void-free and seam-free tungsten gap-filling process.

[0057] In activity 301, method 300 includes receiving the substrate into the processing volume section 215 of the processing chamber 202. In activity 302, method 300 includes forming a nucleation layer 404 on the substrate using a nucleation process. A portion of an exemplary substrate 400 on which the nucleation layer 404 is formed is schematically shown in Figure 4A.

[0058] Here, the substrate 400 is characterized by a patterned surface 401 comprising a dielectric material layer 402 having a plurality of openings 405 (one shown) formed thereon. In some embodiments, the plurality of openings 405 include one or a combination of high aspect ratio via or trench openings having a width of about 1 μm or less, for example, about 800 nm or less or about 500 nm or less, and a depth of about 2 μm or more, for example, about 3 μm or more or about 4 μm or more. In some embodiments, individual openings 405 may have an aspect ratio (depth-to-width ratio) of about 5:1 or more, for example, about 10:1 or more, about 15:1 or more, or between about 10:1 and about 40:1, for example, between about 15:1 and about 40:1. As shown in the figure, the patterned surface 401 conformally lines the opening 405 and includes a barrier or adhesive layer 403 (e.g., a titanium nitride (TiN) layer) deposited on the dielectric material layer 402 to facilitate the subsequent deposition of the tungsten nucleation layer 404. In some embodiments, the adhesive layer 403 is deposited to a thickness between about 2 angstroms (Å) and about 100 Å.

[0059] In some embodiments, Method 300 includes depositing an adhesive layer 403 using a second processing chamber of a multi-chamber processing system 800, such as the one shown in Figure 8, before accepting the substrate into the processing chamber 202. In some embodiments, Method 300 includes sequentially depositing the adhesive layer 403 and the nucleating layer 404 within the same processing chamber 202. In some embodiments, the adhesive layer 403 functions as a nucleating layer that allows for subsequent bulktungsten deposition thereon. In embodiments where the adhesive layer 403 functions as a nucleating layer, Method 300 may not include Activity 302.

[0060] In some embodiments, the nucleation layer 404 is deposited using an atomic layer deposition (ALD) process. Generally, the ALD process involves repeating cycles of alternately exposing the substrate 400 to a tungsten-containing precursor and the substrate 400 to a reducing agent, and purging the processing area 221 between alternating exposures. Examples of suitable tungsten-containing precursors include tungsten halides such as tungsten hexafluoride (WF6), tungsten hexachloride (WCl6), or combinations thereof. Examples of suitable reducing agents include hydrogen gas (H2), borane, e.g., B2H6, and silane, e.g., SiH4, Si2H6, or combinations thereof. In some embodiments, the tungsten-containing precursor includes WF6, and the reducing agent includes B2H6, SiH4, or combinations thereof. In some embodiments, the tungsten-containing precursor includes organometallic precursors and / or fluorine-free precursors, such as MDNOW (methylcyclopentadienyl-dicarbonylnitrosyl-tungsten), EDNOW (ethylcyclopentadienyl-dicarbonylnitrosyl-tungsten), tungsten hexacarbonyl (W(CO)6), or combinations thereof.

[0061] During the nucleation process, the processing volume section 215 is generally maintained at a pressure of less than about 120 Torr, for example, between about 900 mTorr and about 120 Torr, between about 1 Torr and about 100 Torr, or for example, between about 1 Torr and about 50 Torr. Exposure of the substrate 400 to the tungsten-containing precursor includes flowing the tungsten-containing precursor from the deposition gas source 240 to the processing area 221 at a flow rate of more than about 10 sccm, for example, between about 10 sccm and about 1000 sccm, for example, between about 10 sccm and about 750 sccm, or between about 10 sccm and about 500 sccm. Exposure of the substrate 400 to the reducing agent includes flowing the reducing agent from the deposition gas source 240 to the processing area 221 at a flow rate of between about 10 sccm and about 1000 sccm, for example, between about 10 sccm and about 750 sccm. It should be noted that the flow rates for the various deposition and processing processes described herein are for processing system 200 configured to process substrates with a diameter of 300 mm. Appropriate scaling may be used in processing systems configured to process substrates of different sizes.

[0062] Here, the tungsten-containing precursor and the reducing agent are each passed through the processing area 221 for periods of approximately 0.1 seconds and approximately 10 seconds, for example, approximately 0.5 seconds and approximately 5 seconds. The processing area 221 can be purged between alternating exposures by passing an inert purge gas, such as argon (Ar), through the processing area 221 for periods of approximately 0.1 seconds and approximately 10 seconds, for example, approximately 0.5 seconds and approximately 5 seconds. The purge gas can be supplied from a deposition gas source 240 or a bypass gas source 238. Generally, the repetition of the nucleation process cycle continues until the nucleation layer 404 has a thickness of approximately 10 Å and approximately 200 Å, for example, approximately 10 Å and approximately 150 Å, or approximately 20 Å and approximately 150 Å.

[0063] In activity 303, method 300 includes treating the nucleation layer 404 to suppress tungsten deposition on the field surface of the substrate 400 and to form differential suppression profiles within a plurality of openings 405 by using a differential suppression process. Generally, forming differential suppression profiles involves exposing the nucleation layer 404 to an activated nuclide of a treatment gas, e.g., a treatment radical 406 shown in Figure 4B. Suitable treatment gases that can be used in the suppression process include N2, H2, NH3, NH4, O2, CH4, or combinations thereof. In some embodiments, the treatment gas includes nitrogen such as N2, H2, NH3, NH4, or combinations thereof, and the activated nuclide includes nitrogen radicals, e.g., atomic nitrogen. In some embodiments, the treatment gas is combined with an inert carrier gas such as Ar, He, or combinations thereof to form a treatment mixed gas.

[0064] Although not bound by theory, it is thought that the activated nitrogen nuclide (treated radical 406) is incorporated into a portion of the nucleation layer 404 by adsorption of the activated nitrogen nuclide and / or by reaction with metallic tungsten in the nucleation layer 404, thereby forming a tungsten nitride (WN) surface. The adsorbed nitrogen and / or nitrided surface of the tungsten nucleation layer 404 preferably delays (inhibits) further tungsten nucleation, and therefore subsequent tungsten deposition thereon.

[0065] Generally, the diffusion of treated radicals 406 into multiple openings 405 is controlled to produce a desired inhibition gradient within the openings 405 of the feature area. Here, the diffusion of treated radicals 406 is controlled such that the tungsten growth inhibition effect at the walls of the openings 405 decreases with increasing distance from the field of the patterned surface 401 (Figures 4B-4C). As a result, tungsten nucleation is more easily established at or near the bottom of the feature area, and once established, tungsten growth (deposition of gap-filling material 408) within the openings 405 accelerates from the point of nucleation (e.g., from uninhibited or low-inhibition areas at the bottom of the openings 405), enabling bottom-up seamless tungsten gap-filling. The direction of the inhibition gradient from high-inhibition areas to uninhibited or low-inhibition areas is indicated by arrow 417 (Figure 4C). The diffusion of the treated radicals 406 into the opening 405 generally depends at least partially on the size and aspect ratio of the opening 405 and can be regulated, in particular, by controlling the energy, flux, and, depending on the embodiment, the directionality of the treated radicals 406 on the patterned surface 401.

[0066] In some embodiments, exposing the nucleating layer 404 to the treatment radicals 406 includes using a first radical generator 206A to form a substantially halogen-free treatment mixture gas treatment plasma 282A and flowing the emissions of the treatment plasma 282A into a treatment area 221. In some embodiments, the flow rate of the treatment mixture gas to the first radical generator 206A, and therefore the flow rate of the treatment plasma emissions into the treatment area 221, is between about 1 sccm and about 3000 sccm, for example, between about 1 sccm and about 2500 sccm, between about 1 sccm and about 2000 sccm, between about 1 sccm and about 1000 sccm, between about 1 sccm and about 500 sccm, between about 1 sccm and about 250 sccm, between about 1 sccm and about 100 sccm, or between about 1 sccm and about 75 sccm, for example, between about 1 sccm and about 50 sccm.

[0067] In some embodiments, the flow rate of the treatment mixed gas to the first radical generator 206A is between about 50 sccm and about 3000 sccm, for example, between about 50 sccm and about 2500 sccm, between about 50 sccm and about 2000 sccm, between about 50 sccm and about 1000 sccm, between about 50 sccm and about 500 sccm, or between about 50 sccm and about 250 sccm. In some embodiments, the flow rate of a substantially halogen-free treatment gas, such as N2, is between about 1 sccm and about 200 sccm, for example, between about 1 sccm and about 100 sccm, and the flow rate of the inert carrier gas is between about 50 sccm and about 3000 sccm, for example, between about 50 sccm and about 2000 sccm, or between about 100 sccm and about 2000 sccm.

[0068] In some embodiments, the suppression process includes exposing the substrate 400 to the treatment radicals 406 for a period of about 5 seconds or more, for example, about 6 seconds or more, about 7 seconds or more, about 8 seconds or more, about 9 seconds or more, about 10 seconds or more, or between about 5 seconds and about 120 seconds, for example, between about 5 seconds and about 90 seconds, or between about 5 seconds and about 60 seconds, or between about 5 seconds and about 30 seconds, for example, between about 5 seconds and about 20 seconds.

[0069] In some embodiments, the concentration of substantially halogen-free process gas in the process gas mixture is between about 0.5 vol% and about 50 vol%, for example between about 0.5 vol% and about 40 vol%, between about 0.5 vol% and about 30 vol%, between about 0.5 vol% and about 20 vol%, or, for example, between about 0.5 vol% and about 10 vol%, for example between about 0.5 vol% and about 5 vol%.

[0070] In some embodiments, for example, when the substantially halogen-free treatment gas contains N2, NH3, and / or NH4, the first radical generator 206A can be used to activate atomic nitrogen in amounts between about 0.02 mg and about 150 mg, for example, between about 0.02 mg and about 150 mg, or between about 0.02 mg and about 100 mg, or between about 0.1 mg and about 100 mg, or between about 0.1 mg and about 100 mg, or between about 1 mg and about 100 mg, during the suppression treatment process of a 300 mm diameter substrate. In some embodiments, the first radical generator 206A can be used to activate atomic nitrogen in amounts of approximately 0.02 mg or more, for example, approximately 0.2 mg or more, approximately 0.4 mg or more, approximately 0.6 mg or more, approximately 0.8 mg or more, approximately 1 mg or more, approximately 1.2 mg or more, approximately 1.4 mg or more, approximately 1.6 mg or more, approximately 1.8 mg or more, approximately 2 mg or more, approximately 2.2 mg or more, approximately 2.4 mg or more, approximately 2.6 mg or more, approximately 2.8 mg or more, or approximately 3 mg or more, during the suppression treatment process of a 300 mm diameter substrate. Appropriate scaling may be used in a processing system configured to process substrates of different sizes.

[0071] In other embodiments, the treatment radicals 406 can be formed using a remote plasma (not shown) that is ignited and maintained in a portion of the treatment volume section 215 separated from the treatment area 221 by the showerhead 218, for example, between the showerhead 218 and the lid plate 216. In those embodiments, the activated treatment gas can be passed through an ion filter before the treatment radicals 406 reach the surface of the treatment area 221 and the substrate 400 in order to remove substantially all ions from it. In some embodiments, the showerhead 218 may be used as an ion filter. In other embodiments, the plasma used to form the treatment radicals is an in-site plasma formed in the treatment area 221 between the showerhead 218 and the substrate 400. In some embodiments, for example, when using an in-site treatment plasma, the substrate 400 can be biased to control the directionality and / or accelerate ions formed from the treatment gas, such as charged treatment radicals, toward the substrate surface.

[0072] In some embodiments, the suppression process includes maintaining the processing volume section 215 at a pressure of less than about 100 Torr while the activation gas is flowed through it. For example, during the suppression process, the processing volume section 215 may be maintained at a pressure of less than about 75 Torr, e.g., less than about 50 Torr, less than about 25 Torr, less than about 15 Torr, or between about 0.5 Torr and about 120 Torr, e.g., between about 0.5 Torr and about 100 Torr, or between about 0.5 Torr and about 50 Torr, or, e.g., between about 1 Torr and about 10 Torr.

[0073] In Activity 304, Method 300 includes selectively depositing tungsten gap-filling material 408 into a plurality of openings 405 according to the differential suppression profile established by the suppression treatment in Activity 303 (Figures 4C-4D). In one embodiment, the tungsten gap-filling material 408 is formed using a low-stress chemical vapor deposition (CVD) process that includes simultaneously flowing (in parallel) a tungsten-containing precursor gas and a reducing agent into a processing area 221 and exposing the substrate 400 to it. The tungsten-containing precursor and reducing agent used in the tungsten gap-filling CVD process may include any combination of tungsten-containing precursor and reducing agent described in Activity 301. In some embodiments, the tungsten-containing precursor comprises WF6 and the reducing agent comprises H2.

[0074] Here, the tungsten-containing precursor is flowed into the processing area 221 at a rate between approximately 50 sccm and approximately 1000 sccm, or greater than approximately 50 sccm, or less than approximately 1000 Torr, or between approximately 100 sccm and approximately 900 sccm. The reducing agent is flowed into the processing area 221 at a rate greater than approximately 500 sccm, for example greater than approximately 750 sccm, greater than approximately 1000 sccm, or between approximately 500 sccm and approximately 10000 sccm, for example between approximately 1000 sccm and approximately 9000 sccm, or between approximately 1000 sccm and approximately 8000 sccm.

[0075] In some embodiments, tungsten gap-filling CVD process conditions are selected to provide tungsten features with relatively lower residual film stress compared to conventional tungsten CVD processes. For example, in some embodiments, the tungsten gap-filling CVD process includes heating the substrate to a temperature of about 250°C or higher, for example, about 300°C or higher, or between about 250°C and about 600°C, or between about 300°C and about 500°C. During the CVD process, the processing volume section 215 is generally maintained at a pressure of less than about 500 Torr, less than about 600 Torr, less than about 500 Torr, less than about 400 Torr, or between about 1 Torr and about 500 Torr, for example, between about 1 Torr and about 450 Torr, or between about 1 Torr and about 400 Torr, or for example, between about 1 Torr and about 300 Torr.

[0076] In another embodiment, the tungsten gap-filling material 408 is deposited in activity 304 using an atomic layer deposition (ALD) process. The tungsten gap-filling ALD process involves repeatedly exposing the substrate 400 alternately to a tungsten-containing precursor gas and a reducing agent, and purging the processing area 221 between alternating exposures. The tungsten-containing precursor and reducing agent used in the tungsten gap-filling ALD process may include any combination of the tungsten-containing precursor and reducing agent described in activity 301. In some embodiments, the tungsten-containing precursor comprises WF6 and the reducing agent comprises H2.

[0077] Here, the tungsten-containing precursor and the reducing agent are each passed through the processing area 221 for a period of time such as approximately 0.1 seconds and approximately 10 seconds, for example, approximately 0.5 seconds and approximately 5 seconds. The processing area 221 is generally purged between alternating exposures by passing an inert purge gas such as argon (Ar) through the processing area 221 for a period of time such as approximately 0.1 seconds and approximately 10 seconds, for example, approximately 0.5 seconds and approximately 5 seconds. The purge gas can be supplied from the deposition gas source 240 or the bypass gas source 238.

[0078] Exposure of the substrate 400 to a tungsten-containing precursor may include flowing the tungsten-containing precursor from the deposition gas source 240 to the processing area 221 at flow rates between approximately 10 sccm and approximately 1000 sccm, for example, between approximately 100 sccm and approximately 1000 sccm, between approximately 200 sccm and approximately 1000 sccm, between approximately 400 sccm and approximately 1000 sccm, or between approximately 500 sccm and approximately 900 sccm. Exposure of the substrate 400 to a reducing agent may include flowing the reducing agent from the deposition gas source 240 to the processing area 221 at flow rates between approximately 500 sccm and approximately 10000 sccm, for example, between approximately 500 sccm and approximately 8000 sccm, between approximately 500 sccm and approximately 5000 sccm, or between approximately 1000 sccm and approximately 4000 sccm.

[0079] In some embodiments, the tungsten gap-filling ALD process includes heating the substrate to a temperature of about 250°C or higher, for example, about 300°C or higher, or between about 250°C and about 600°C, or between about 300°C and about 500°C. In some embodiments, the ALD process includes maintaining the processing volume section 215 at a pressure of less than about 150 Torr, less than about 100 Torr, less than about 50 Torr, for example, less than about 30 Torr, or between about 0.5 Torr and about 50 Torr, for example, between about 1 Torr and about 20 Torr.

[0080] In other embodiments, the tungsten gap-filling material 408 is deposited using a pulsed CVD method, which involves repeatedly exposing the substrate 400 to a tungsten-containing precursor gas and a reducing agent in alternating cycles without purging the processing area 221. The processing conditions for the tungsten gap-filling pulsed CVD method can be the same, substantially the same, or within the same range as those described above for the tungsten gap-filling ALD process.

[0081] Beneficially, the tungsten gap-filling process described above allows for relatively low residual stress in the tungsten material formed therefrom. While not bound by theory, it is thought that relatively high substrate temperatures, e.g., above 250°C, and increased energy supply increase the diffusion rate of adsorbed atoms to the adsorption sites at the openings, while relatively low processing pressure simultaneously slows down the tungsten gap-filling deposition process. The increased diffusion rate of adsorbed atoms and the decreased deposition rate promote an improved (more regular) atomic arrangement in the deposited tungsten material compared to conventional conformal CVD processes, thereby beneficially resulting in lower residual film stress in the tungsten gap-filling material. For example, in some embodiments, a blanket tungsten layer deposited to a thickness of about 1200 Å using the processing conditions described above has a residual film stress of less than about 1600 MPa, less than about 1500 MPa, less than about 1400 MPa, less than about 1300 MPa, less than about 1200 MPa, less than about 1100 MPa, less than about 1000 MPa, less than about 900 MPa, less than about 800 MPa, less than about 700 MPa, or in some embodiments, less than about 600 MPa.

[0082] In a typical semiconductor manufacturing process, a chemical mechanical polishing (CMP) process can be used to remove the tungsten overburden (and the barrier layer placed beneath it) from the field surface of the substrate after depositing tungsten gap-filling material 408 into the openings 405. The CMP process generally relies on a combination of chemical and mechanical activity to facilitate the uniform removal of the overburden layer 410 and an endpoint detection method to determine when the tungsten overburden has been removed from the field surface. Uneven removal of tungsten from the field surface or failure to detect the polishing endpoint can result in undesirable over-polishing or under-polishing of at least some areas of the substrate surface. Since the polishing fluids in the CMP process are often corrosive and can cause damage to feature areas during over-polishing, tungsten over-polishing can result in undesirable removal of tungsten from tungsten feature areas, such as feature area coring. Tungsten under-polishing can result in undesirable residual tungsten remaining on the field surface after CMP.

[0083] Unfortunately, the suppression treatment used to provide seam-free and void-free tungsten features by promoting bottom-up growth of tungsten also suppresses tungsten growth on the field surface, preventing the formation of a uniform tungsten overburden during the bulk tungsten process. Therefore, embodiments of this specification include a process for depositing an overburden layer different from the process used to deposit the tungsten gap-filling material 408, which can provide a uniform thickness of tungsten on the field surface of the substrate in a subsequent CMP process.

[0084] In activity 305, method 300 optionally includes forming a second nucleation layer 409 using a second nucleation process (Figure 4D). In activity 306, method 300 includes forming an overbaden layer 410 using an overbaden process. The second nucleation process and / or overbaden process are used to reduce and / or eliminate the tungsten growth inhibition on the field surface of the substrate given by the inhibition process in activity 303. By reducing and / or reversing the inhibition effect, the field surface is prepared to allow the growth and / or deposition of overbaden of tungsten material. The overbaden layer 410 can be used to facilitate uniform processing in a subsequent chemical mechanical polishing (CMP) process.

[0085] In some embodiments, the second nucleation layer 409 is deposited using an ALD process that is the same as or substantially the same as the ALD process used to form the (first) nucleation layer 404 in activity 302, or an ALD process having processing conditions within the range detailed in the ALD process in activity 302. When used, the second nucleation layer 409 may be deposited to a thickness between about 5 Å and 100 Å, or between about 10 Å and 80 Å, or, for example, between about 20 Å and 60 Å.

[0086] The process used to deposit the overbaden layer 410 in Activity 306 may be a CVD or ALD process that is the same as or substantially the same as the CVD or ALD process used to deposit the gap-filling tungsten material in Activity 304, or an ALD process having processing conditions within the range detailed in the process in Activity 302. In other embodiments, the overbaden layer is deposited using a CVD process having a processing pressure greater than the processing pressure used in the tungsten gap-filling process in Activity 302. For example, in some embodiments, the ratio of the processing pressure used to deposit the overbaden layer 410 to the processing pressure used to deposit the tungsten gap-filling material 408 is about 1.25:1 or greater, e.g., about 1.5:1 or greater, about 1.75:1 or greater, about 2:1 or greater, about 2.25:1 or greater, about 2.5:1 or greater, about 2.75:1 or greater, about 3:1 or greater, about 3.25:1 or greater, or about 3.5:1 or greater. Increasing the processing pressure in the overbaden process is advantageous because it leads to an increase in the deposition rate and a reduction in the substrate processing time. Here, the overbaden layer is deposited to a thickness between approximately 500 Å and approximately 6000 Å, for example, between approximately 1000 Å and approximately 5000 Å.

[0087] In activity 307, method 300 includes transferring the processed substrate 400 out of the processing chamber 202, and resuming in activity 301 by receiving the substrate to be processed into the processing chamber 202. In some embodiments, method 300 further includes periodically cleaning the processing chamber 202 during the processing of substrates by using a chamber cleaning process in activity 308. The cleaning process is used to remove undesirable process residues, such as accumulated tungsten residues, from the internal surface of the processing volume section 215. In some embodiments, the chamber cleaning process is performed after the number of substrates sequentially processed in the processing chamber 202 exceeds a threshold, for example, two or more substrates, three or more substrates, five or more substrates, seven or more substrates, nine or more substrates, or eleven or more substrates.

[0088] In activity 308 of method 300, the chamber cleaning process generally includes activating a cleaning gas in a remote plasma source and flowing the activated cleaning gas into the processing chamber 202. Generally, the cleaning gas mixture includes a halogen-containing gas and a carrier gas such as argon or helium. Examples of suitable halogen-containing gases that can be used in the cleaning gas mixture include NF3, F2, SF6, CL2, CF4, C2F6, C4F8, CHF3, CF6, CCl4, C2Cl6, and combinations thereof. In some embodiments, the cleaning gas further includes a diluent gas such as Ar, He, or combinations thereof. For example, in one embodiment, the cleaning gas mixture includes NF3 and Ar or He. Generally, the active nuclides of the cleaning gas mixture, such as halogen radicals, react with tungsten residue accumulated on the surface of the processing chamber 202 to form volatile tungsten nuclides. The volatile tungsten nuclides are discharged from the processing volume section 215 through the exhaust section 217.

[0089] In some embodiments, the flow rate of the cleaning mixed gas to the remote plasma source, and therefore the flow rate of the activated cleaning mixed gas to the processing volume section 215, is about 500 sccm or more, for example, about 1000 sccm or more, 1500 sccm or more, about 2000 sccm or more, or about 2500 sccm or more. The concentration of halogen-containing gas in the cleaning mixed gas is generally between about 5 volume% and about 95 volume%, for example, between about 5 volume% and about 70 volume%, between about 10 volume% and about 95 volume%, or more than about 10 volume%.

[0090] In some embodiments, the activated cleaning mixture gas is flowed through the processing volume section 215 for a period of about 5 seconds or more, about 10 seconds or more, or about 15 seconds or more. In some embodiments of the chamber cleaning process, a remote plasma source can be used to activate atomic halogens, such as fluorine or chlorine, in a processing chamber sized to process a 300 mm diameter substrate, in amounts of about 5 mg or more, for example, about 10 mg or more, about 15 mg or more, about 20 mg or more, about 25 mg or more, about 30 mg or more, about 35 mg or more, about 40 mg or more, about 45 mg or more, or for example, about 50 mg or more, in a processing chamber sized to process a substrate with a diameter of 300 mm. Appropriate scaling can be used in processing chambers sized to process substrates of different sizes.

[0091] Here, the chamber cleaning process is performed using a remote plasma source (e.g., a second radical generator 206B) different from the remote plasma source (e.g., a first radical generator 206A) used to generate processing radicals in activity 303. For example, here, the chamber cleaning process includes flowing a cleaning mixture gas into the second radical generator 206B, igniting and maintaining the cleaning plasma 282B of the cleaning mixture gas, and flowing the emissions of the cleaning plasma 282B into the processing volume section 215. Generally, performing the chamber cleaning process each time after each substrate has been processed in the processing chamber 202 is undesirable because it impairs the substrate processing capacity. Therefore, the chamber cleaning process is generally performed after multiple substrates have been processed in the chamber, and thus the average number of substrates processed during the chamber cleaning process is about two or more substrates, for example, about five or more substrates, about ten or more substrates, about fifteen or more substrates, or about twenty or more substrates.

[0092] Using a dedicated plasma source (first radical generator 206A) for the suppression process in Activity 303 is preferable, as it allows for improved processing stability of the suppression process compared to using a common plasma source for both the suppression process and the chamber cleaning process. This is probably because the plasma formed from the processing gas is substantially less corrosive than the plasma formed from the halogen-based cleaning gas, thereby resulting in relatively lower ion-based damage to the surface within the first radical generator 206A. Nevertheless, when a dedicated processing plasma source is used for the formation of nitrogen-processed radicals, at least some drift in processing performance at the substrate edge, e.g., degradation of suppression performance at the substrate edge, was observed over time.

[0093] While not bound by theory, it is conceivable that activated nitrogen nuclides may be adsorbed onto the plasma-facing surface of a remote plasma source and the surface of the conduit between the remote plasma source and the processing chamber, and / or undergo nitridation. Adsorbed nitrogen and / or nitrided surfaces 407 reduce the processing plasma efficiency, for example, by decreasing the dissociation rate of the processing gas and / or promoting the recombination of activated nitrogen nuclides exposed to it, thereby resulting in a decrease in radical concentration and flux on the substrate surface. Therefore, in some embodiments, the first radical generators 206A are periodically tuned by igniting and maintaining the plasma from a relatively low flow rate and / or concentration of halogen-containing gas to remove adsorbed nitrogen and / or nitride from their surfaces, as described in activity 309. The plasma source tuning process is used to activate the surface of the first radical generators 206A to extend the lifetime of the processing radicals that are subsequently formed thereon. Generally, extending the lifetime of the processing radicals makes it possible to increase the number of substrates that can be processed during the chamber cleaning process.

[0094] In Figure 3, the plasma source conditioning process is shown to be performed after the processed substrate has been transferred from the processing chamber 202 and before the next substrate to be processed is received into the processing chamber 202. In other embodiments, the plasma source conditioning process may be performed while the substrate is positioned on the substrate support 222, for example, before the differential suppression process in activity 303 (as indicated by the dashed line), after the differential suppression process in activity 303, or before, after, or concurrently with any of the nucleation, gap filling, and overbaden processes in activities 302, 304, 305, and 306, respectively.

[0095] In Activity 309, Method 300 includes passing a conditioned gas mixture through a first radical generator 206A and activating the conditioned gas mixture by igniting and maintaining its plasma. Here, the conditioned gas mixture includes a halogen-containing gas and an inert carrier gas such as Ar, He, or a combination thereof. Suitable halogen-containing gases that can be used in the conditioned gas mixture are described in Activity 308. In some embodiments, the halogen-containing gas includes NF3.

[0096] In some embodiments, the halogen-containing gas is present in amounts between about 0.1 volume% and about 50 volume% of the conditioned gas mixture, for example, between about 0.1 volume% and about 40 volume%, between about 0.1 volume% and about 30 volume%, between about 0.1 volume% and about 25 volume%, or for example, between 0.1 volume% and about 25 volume%. The conditioned gas mixture is flowed through the first radical generator 206A at a flow rate between about 100 sccm and about 2000 sccm, and the plasma of the conditioned gas mixture is ignited and maintained for a period between about 1 second and about 30 seconds, or between about 1 second or more, or between about 30 seconds or less. In some embodiments, the halogen-containing gas can be introduced into the first radical generator 206A at an effective flow rate between approximately 0.1 sccm and approximately 30 sccm, for example, between approximately 0.1 sccm and approximately 20 sccm, between approximately 0.1 sccm and approximately 10 sccm, or between approximately 0.1 sccm and approximately 5 sccm. Here, the effective flow rate is equal to the flow rate of the adjusted mixed gas multiplied by the volume % of the halogen-containing gas.

[0097] In some embodiments, the first radical generator 206A can be used to activate an atomic halogen such as fluorine or chlorine in amounts between about 0.002 mg and about 40 mg, for example, between about 0.002 mg and about 35 mg, or between about 0.02 mg and about 30 mg, or between about 0.02 mg and about 25 mg, or between about 0.02 mg and about 20 mg, or between about 0.02 mg and about 15 mg, during the plasma source condition process. In some embodiments, the first radical generator 206A can be used to activate an atomic halogen in amounts between at least about 0.02 mg and at most about 40 mg, for example, at most about 35 mg, at most about 30 mg, at most about 25 mg, at most about 20 mg, at most about 15 mg, at most about 10 mg, etc., or at least about 0.02 mg and at most about 8 mg, during the plasma source condition process.

[0098] In some embodiments, it may be desirable to limit the amount of halogen radicals exposed to the internal surface of the first radical generator 206A during the plasma suppression process. In those embodiments, for example, the weight ratio (fluorine (mg) / nitrogen (mg) or chlorine (mg) / nitrogen (mg)) of the activated halogen nuclide generated in the first radical generator 206A during the plasma source condition process to the activated nitrogen radicals generated in the subsequent suppression process may be at most 5:1, e.g., at most 4:1, at most 3:1, or at most 2:1, e.g., at most 1:1, etc.

[0099] As discussed above, plasma source condition processes are beneficial in improving processing uniformity between substrates and within substrates. Although not bound by theory, it is thought that activated nitrogen nuclides used in suppression processing processes adsorb onto the surface of the conduit between the source and the chamber, and the nitrided surface then promotes the recombination rate of the activated nitrogen nuclides flowing through it. Plasma source condition processes are beneficial in removing nitrogen nuclides from the surfaces between substrates, which in turn helps to reduce the recombination rate and extend the lifetime of the processed radicals.

[0100] Figure 5 shows a method 500 for processing a substrate according to another embodiment, which can be performed using the processing system 200 described in Figures 2A to 2B. Any of the activities and / or processing conditions described in method 500 are intended to be used in combination with or instead of the activities and / or processing conditions described in method 300. Figures 6A to 6D are schematic cross-sectional views of a portion of a substrate 400 showing various aspects of method 500 at different stages of the void-free and seam-free tungsten gap-filling process scheme. Figure 6A schematically shows a substrate 600 after performing activities 501 to 503 of method 500.

[0101] In activity 501, method 500 includes receiving the substrate 600 into the processing volume section 215 of the processing chamber 202. The substrate 600 features a patterned surface 401 comprising a dielectric material layer 402 having a plurality of openings 405 (one shown) formed therein, and may include any one of the features and / or attributes of the substrate 400 shown in Figures 4A to 4D, such as a conformal adhesive layer 403.

[0102] In activity 502, method 500 includes depositing a first nucleation layer 404. The first nucleation layer 404 can be deposited using the nucleation process described in activity 302 of method 300.

[0103] In Activity 503, Method 500 includes depositing a conformal tungsten layer 605 on a first nucleation layer 404. The conformal tungsten layer 605 may be deposited using any one or a combination of the low-stress CVD, ALD, or pulsed CVD processes and / or processing conditions described in the selective gap-filling process of Activity 304. Here, the tungsten layer 605 is deposited on an unsuppressed tungsten nucleation layer 404 and is thereby conformal to the patterned surface 401 of the substrate 600 and can conformally line, for example, an opening 405 formed therein. In some embodiments, the conformal tungsten layer 605 may be deposited to a thickness greater than about 50 angstroms (Å), for example, between about 50 Å and about 1000 Å, or between about 50 Å and about 500 Å.

[0104] In activity 504, method 500 includes depositing a second nucleation layer 607 on the conformal tungsten layer 605 (Figure 6B). In some embodiments, the second nucleation layer 607 is formed using the same process used to form the first nucleation layer 404, or a different process within the same range of processing conditions.

[0105] In activity 505, method 500 includes treating the second nucleation layer 607 to suppress tungsten deposition on the field surface of the substrate 600 and forming differential suppression profiles within a plurality of openings 405 by using a differential suppression process. Activity 505 is shown in Figure 6B and can be performed using any one of the processes or processing conditions described in activity 303 of method 300.

[0106] In some embodiments, method 500 includes performing a plasma source adjustment process (activity 509) after forming the second nucleation layer 607 in activity 504 and before performing the suppression treatment of activity 505. In those embodiments, the stacked layers of the first nucleation layer 404, conformal tungsten layer 605, and second nucleation layer 607 can protect the underlying surface from etching and / or damage caused by exposure to emissions (halogen radicals) of the plasma source adjustment process.

[0107] In activity 506, method 500 includes selectively depositing bulk gap-filling material 408 into a plurality of openings 405 according to the differential suppression profile established by the suppression treatment in activity 505 (Figures 6C-6D). Activity 506 can be performed using any one or a combination of the processes or processing conditions used in the selective gap-filling process described in activity 304 of method 300.

[0108] In activity 507, method 500 includes transferring the substrate 600 out of the processing chamber 202, and in some embodiments, transferring the substrate to be processed into the processing chamber 202, and repeating method 500.

[0109] In some embodiments, Method 500 further includes performing a chamber cleaning process in Activity 508 and / or a plasma source conditioning process in Activity 509. Activities 508 and 509 can be performed using any one or combination of the processes, processing conditions, and / or sequences of the steps described in Activities 308 and 309 of Method 300, respectively.

[0110] In some embodiments, method 500 further includes causing a tungsten material overbaden layer 609 to form on the field surface of the substrate 600. In some embodiments, forming the overbaden layer 609 further includes continuing the gap-filling process in activity 506 until the suppression effect of the field surface is overcome and the tungsten material can be deposited thereon. In other embodiments, the overbaden layer 609 can be formed using one or a combination of the processes described in activities 305 and 306 of method 300.

[0111] The methods and systems provided above can preferably be used to reduce process variations between substrates, improve in-substrate processing uniformity, and simultaneously enable improved substrate processing throughput and reduced substrate processing costs. The improved processing stability and in-substrate processing uniformity provided by the above-described systems and methods were demonstrated by the experimental results shown in Figures 7A and 7B.

[0112] Figure 7A is graph 700A showing the processing results of multiple substrates processed in the processing system without using the plasma source condition processes described in Activities 309 and 509. Figure 7B is graph 700B showing the processing results of multiple substrates processed using the plasma source condition processes described in Activities 309 and 509. In each of Figures 7A and 7B, multiple 300 mm diameter substrates, each having a tungsten nucleation layer formed on top, were exposed to nitrogen-treated radicals formed using a dedicated remote plasma source, e.g., the first radical generator 206A, and then a layer of tungsten was subsequently deposited thereon using a tungsten gap-filling process, such as that described in Activity 304.

[0113] In Figure 7A, multiple substrates (300 substrates) were processed sequentially without the use of a plasma source condition process, so that the first radical generator 206A was not exposed to halogen-containing cleaning gas between suppression processes. In Figure 7B, multiple substrates (600 substrates) were processed sequentially using the same conditions as those used for the substrates in Figure 7A, except that the remote plasma source (first radical generator 206A) was adjusted using the plasma source condition process of activity 309 between each suppression process. The resulting tungsten thickness was measured at the center of each substrate and at radii of 50 mm (lines 702A-702B), 100 mm (lines 704A-704B), and 147 mm (lines 706A-706B). The tungsten thickness measurements obtained at the center of each substrate are not shown to reduce visual confusion, but were within approximately ±2.5% of the thickness measurements at radii of 50 mm (lines 702A-702B) and 100 mm (lines 704A-704B).

[0114] As can be seen in Figure 7A, the suppression effect at the edge of substrate 706A (as indicated by the thickness of the tungsten material deposited thereon) decreases over the course of the first 50 consecutively processed substrates, while the suppression effect in the region radially inward from the edge remains relatively stable across substrates. In contrast, in Figure 7B, the suppression effect at the edge of substrate 706B remains relatively stable over more than 600 consecutively processed substrates compared to the regions radially inward from there, 702B and 704B.

[0115] In a typical processing system 200 where the gas inlet 223 is centrally located through the lid plate 216, the activated nitrogen nuclide used to process the substrate edge travels a greater distance to reach the substrate surface than the activated nuclide used to process surface regions located radially inward from the substrate edge. While not bound by theory, it is conceivable that a greater travel distance could result in reduced excitation of the activated nuclide or increased recombination of the activated nuclide at the substrate edge. An undesirable reduction in the concentration and flux of the processed radicals at the substrate edge is thought to result in a corresponding reduction in the suppression effect thereafter. Therefore, the improved in-substrate uniformity and reduced inter-substrate processing variation demonstrated in Figures 7A-7B are thought to be a result of increased radical lifetime and / or the generation of at least metastable radical nuclides enabled by the plasma source condition process. In embodiments herein, metastable radical nuclides are radicals with a lifetime of about 3 seconds or more, e.g., nitrogen-processed radicals.

[0116] In some embodiments, the above-described method can be carried out using a multi-chamber processing system 800, such as that shown in Figure 8. Here, the multi-chamber processing system 800 includes a plurality of system loading stations for receiving substrates, in this case a load lock station 802. The load lock station 802 can be sealed and is generally coupled to a vacuum machine, such as one or more vacuum pumps, which can be used to evacuate gases from there and maintain the load lock station 802 in a near-atmospheric pressure state. A substrate handler 830, located in a transfer chamber 811, is used to move the substrate 230 between the load lock station 802 and one or more processing chambers 812, 814, 202. Each processing chamber 812 and 814 can be configured to perform at least one of the following substrate deposition processes, such as periodic layer deposition (CLD), atomic layer deposition (ALD), chemical vapor deposition (CVD), physical vapor deposition (PVD), etching, degassing, pre-clean orientation, annealing, and other substrate processes. The processing system 200 is shown in Figures 2A to 2B and is configured to perform the tungsten gap filling processing method described herein.

[0117] Advantageously, the processing systems 200, 800 described above are configured to accommodate different processing conditions desirable for each of the nucleation, suppression, gap-filling deposition, and overburden deposition processes within a single processing chamber 202 without removing the substrate therefrom. The processing system 200 is further configured to reduce processing variability, e.g., in-substrate processing non-uniformity and inter-substrate processing variability, thereby enabling a preferably wider processing window for achieving void-free, seam-free, and / or low-stress tungsten features.

[0118] While the foregoing applies to embodiments of the present disclosure, other and further embodiments of the present disclosure may be devised without departing from the basic scope of the present disclosure, and the scope of the present disclosure is determined by the following claims. [Explanation of Symbols]

[0119] 11 Patterned surfaces 12 Dielectric layer 14 Barrier material layer 15 Tungsten layer 20 Void 24 seams 200 processing systems 202 Processing Chamber 204 Gas supply system 208 System Controller 210 Lid Assembly 212 Side wall 214 Chamber Base 215 Processing volume section 216 Lid Plate 217 Exhaust section 218 Shower Head 219 Gas distribution volume section 220 PCB support assembly 221 Processing area 222 Substrate support 223 Gas Inlet 225 Blocker Plate 226 Ring Channels 227 First Ring Liner 228 The Second Rainer 229 Heater 230 circuit boards 231 First power supply 232 Opening 235 Shadow Ring 236 Purge Ring 237 Purge gas source 238 Gas sources 240 Sedimentary gas sources 262 Support shaft 263 First heater 264 Second Heater 265 Bellows 266-pin assembly 267 pins 268 Pin Hoop 271 doors 272 Vacuum source 280 Chamber body 283 Plasma-facing surface 291 Diverter Valve 292 Dielectric Materials 294 Conduit System 294 CPU 296 memory 297 Support Circuit 300 ways 301 Activities 302 Activities 303 Activities 304 Activities 305 Activities 306 Activities 307 Activities 308 Activities 309 Activities 400 circuit boards 401 Patterned Surface 402 Dielectric material layer 403 Adhesive layer 404 First nucleation layer 405 Opening 406 Processed Radicals 407 Surface 408 Gap filling materials 409 Second nucleation layer 410 layers 417 Arrow 500 ways 501 Activities 502 Activities 503 Activities 504 Activities 505 Activities 506 Activities 507 Activities 508 Activities 509 Activities 605 Tungsten layer 607 Second nucleation layer 609 layers 800 Multi-Chamber Processing System 802 Road Lock Station 811 Transfer Chamber 812 Processing Chamber 814 Processing Chamber 830 PCB Handler 10A circuit board 10B board 15A Feature section 15B layer 206A First Radical Generator 206B Second Radical Generator 281A First plasma chamber volume section 281B Second plasma chamber volume section 282A Processing Plasma 282B Cleaning Plasma 287A First gas source 287B Second gas source 290A First valve 290B Second valve 293A~293B Power supply 294A~294F Conduit 700A Graph 700B Graph 702A Line 702B Line 704A~704B line 706A circuit board 706B circuit board

Claims

1. A substrate processing system, A processing chamber comprising a chamber lid assembly, one or more chamber sidewalls, and a chamber base that collectively define the processing volume section, A gas supply system fluidly coupled to the processing chamber, comprising a first radical generator and a second radical generator, A non-temporary computer-readable medium containing instructions for performing a method of processing multiple boards when executed by a processor, wherein the method is (a) Receiving the substrate into the processing volume section, (b) Exposing the substrate to an activation gas, wherein the activation gas contains the emissions of the processing plasma formed in the first radical generator, (c) Exposing the substrate to a first tungsten-containing precursor and a first reducing agent to deposit a tungsten gap-filling material, (d) Transferring the substrate out of the processing volume section, (e) Adjusting the first radical generator before or after (a), i. Flowing a regulating gas through the first radical generator, wherein the regulating gas contains halogen components, and ii. Ignite the adjustment plasma of the adjustment gas and maintain it for the first period. This includes making adjustments, (f) If the number of substrates processed consecutively is below a threshold, repeat (a) to (e) and Non-temporary computer-readable media, including Includes, The method described above is The process further includes forming a first tungsten nucleation layer after (a) and before (b), The method described above is (b) Before that, a conformal tungsten layer is formed on the first tungsten nucleating layer, Forming a second tungsten nucleation layer on the conformal tungsten layer It further includes, The substrate includes a material layer in which a plurality of openings are formed, A processing system in which exposing the substrate to the activation treatment gas differentially suppresses tungsten deposition on the field surface of the substrate compared to the surfaces within the plurality of openings.

2. The method described above is (g) If the number of substrates processed consecutively is equal to or greater than the threshold, the chamber surface in the processing volume section is exposed to the activating cleaning gas. The activated cleaning gas contains the emissions of the cleaning plasma formed in the second radical generator, and exposure to it is... (h)(a) to (g) are repeated and The processing system according to claim 1, further comprising:

3. The processing system according to claim 2, wherein the processing plasma is formed of a halogen-free nitrogen-containing gas, and the weight of halogen radicals generated during (e) does not exceed five times the weight of nitrogen radicals generated in the first radical generator during (b).

4. The processing system according to claim 2, wherein the flow rate of the halogen-based component to the first radical generator is less than about 10 sccm.

5. The processing system according to claim 1, wherein forming the first tungsten nucleating layer includes repeating a cycle of alternately exposing the substrate to the first or second tungsten-containing precursor and the first or second reducing agent.

6. The aforementioned gas supply system A first valve is fluidly coupled between the first radical generator and the processing chamber, A second valve is fluidically coupled between the second radical generator and the processing chamber. It further includes, The processing system according to claim 2, wherein exposing the chamber surface to the activating cleaning gas includes fluidly separating the first radical generator from the emissions of the cleaning plasma by using the first valve.

7. The processing system according to claim 6, wherein exposure of the substrate to the activation processing gas includes fluidly separating the second radical generator from the emissions of the processing plasma by using the second valve.

8. A method for processing a substrate, (a) The substrate is received in the processing volume section of the processing system, and the processing system is A processing chamber comprising a chamber lid assembly, one or more chamber sidewalls, and a chamber base that collectively defines the processing volume section, and A gas supply system fluidly coupled to the processing chamber, comprising a first radical generator and a second radical generator. Including acceptance, (b) Exposing the substrate to an activation gas, wherein the activation gas contains the emissions of the processing plasma formed in the first radical generator, (c) Exposing the substrate to a first tungsten-containing precursor and a first reducing agent, (d) Transferring the substrate out of the processing volume section, (e) Adjusting the first radical generator before or after (a), i. Flowing a regulating gas through the first radical generator, wherein the regulating gas contains halogen components, and ii. Ignite the adjustment plasma of the adjustment gas and maintain it for the first period. This includes making adjustments, (f) If the number of substrates processed consecutively is below a threshold, repeat (a) to (e) and Includes, Form a first tungsten nucleation layer after (a) and before (b). It further includes, (b) Before that, a conformal tungsten layer is formed on the first nucleating layer, Forming a second nucleation layer on the conformal tungsten layer It further includes, The substrate includes a material layer in which a plurality of openings are formed, A method wherein exposing the substrate to the activation treatment gas differentially suppresses tungsten deposition on the field surface of the substrate compared to the surfaces within the plurality of openings.

9. (g) If the number of substrates processed consecutively is equal to or greater than the threshold, the chamber surface in the processing volume section is exposed to the activating cleaning gas. The activated cleaning gas contains the emissions of the cleaning plasma formed in the second radical generator, and exposure to it is... (h)(a) to (g) are repeated and The method according to claim 8, further comprising:

10. The method according to claim 9, wherein the processing plasma is formed with a halogen-free nitrogen-containing gas, and the weight of halogen radicals generated during (e) does not exceed five times the weight of nitrogen radicals generated in the first radical generator during (b).

11. The method according to claim 9, wherein the flow rate of the halogen-based component to the first radical generator is less than about 10 sccm.

12. The aforementioned gas supply system A first valve is fluidly coupled between the first radical generator and the processing chamber, A second valve is fluidically coupled between the second radical generator and the processing chamber. It further includes, Exposing the chamber surface to the activating cleaning gas includes fluidly separating the first radical generator from the cleaning plasma emissions by using the first valve. The method according to claim 9, wherein exposing the substrate to the activation treatment gas includes fluidly separating the second radical generator from the treatment plasma emissions by using the second valve.

13. The method according to claim 12, wherein the lid assembly includes a lid plate and a shower head coupled to the lid plate, and the first and second radical generators are fluidly connected to the processing volume through a gas inlet formed through the lid plate.

14. The method according to claim 13, wherein the ejected material of the processing plasma travels a first distance from the first radical generator to the processing volume section, and the ejected material of the cleaning plasma travels a second distance from the second radical generator to the processing volume section, and the first distance is smaller than the second distance.

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