Selective metal removal using flowable polymers

Abstract

Embodiments of the present disclosure relate to methods for selectively removing metallic material from a top surface and sidewalls of a feature. The metal material covered by the flowable polymer material remains unaffected. In some embodiments, the metallic material is formed by physical vapor deposition, resulting in a relatively thin sidewall thickness. Any metal material remaining on the sidewalls after the metal material is removed from the top surface may be etched by an additional etching process. The resulting metal layer at the bottom of the feature facilitates selective metal gap filling of the feature.

Description

Technical Field

[0001] Embodiments of the present disclosure relate to methods of metal removal facilitated by flowable polymers. More particularly, embodiments of the present disclosure relate to methods of selectively removing tungsten relative to flowable polymers within substrate features. Background Art

[0002] The gap filling process is integrated into several semiconductor manufacturing processes. The gap filling process can be used to fill the gap (or feature) with insulating or conductive materials. For example, shallow trench isolation, intermetallic dielectric layer, passivation layer, dummy gate are usually implemented by the gap filling process.

[0003] As device geometries continue to shrink (eg, critical dimensions <20 nm, <10 nm, and smaller) and thermal budgets decrease, defect-free filling of spaces becomes increasingly difficult due to limitations of conventional deposition processes.

[0004] Processes for selective tungsten filling have been implemented, where tungsten can be selectively deposited on a tungsten seed layer. Unfortunately, these processes all require a minimum seed layer thickness. Known PVD processes can provide the necessary seed layer thickness, but the selective tungsten filling process will deposit tungsten material on any exposed seed layer.

[0005] Thus, a method is needed for removing undesirable tungsten deposition from field and sidewall surfaces to enable bottom-up filling by a selective deposition process. Summary of the invention

[0006] One or more embodiments of the present disclosure are directed to a method for selective metal removal. The method includes forming a flowable polymer film on a substrate surface having at least one feature formed therein. The at least one feature has an opening with an opening width at a top surface, at least one sidewall, and a bottom. The at least one feature extends a feature depth from the top surface to the bottom. The flowable polymer film is formed within the at least one feature and has a polymer depth that is less than or equal to the feature depth. At least a portion of the metal material is selectively removed from the top surface without substantially affecting any material below the polymer film.

[0007] Additional embodiments of the present disclosure relate to a method for selective tungsten removal. The method includes depositing a tungsten material on a substrate surface having at least one feature formed therein. The at least one feature has an opening with an opening width at a top surface, at least one sidewall, and a bottom. The at least one feature extends a feature depth from the top surface to the bottom. A flowable polymer film is formed within the at least one feature and has a polymer depth that is less than or equal to the feature depth. At least a portion of the tungsten material is selectively removed from the top surface without substantially affecting the tungsten material below the polymer film. The polymer film is removed to expose the tungsten material below the polymer film. The tungsten material is etched from at least one sidewall. A second metal material is selectively deposited on the tungsten material. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] In order to be able to understand the above-mentioned features of the present disclosure in detail, a more specific description of the present disclosure briefly summarized above may be made with reference to embodiments, some of which are shown in the accompanying drawings. However, it should be noted that the accompanying drawings only show representative embodiments of the present disclosure and are not to be considered as limiting its scope, as the present disclosure may allow other equally effective embodiments.

[0009] The embodiments as described herein are illustrated by way of example and not limitation in the figures of the accompanying drawings in which like references indicate similar components.

[0010] Figure 1 A process flow diagram showing a method according to one or more embodiments;

[0011] Figure 2 shows a cross-sectional view of a substrate feature according to one or more embodiments;

[0012] Figures 3 to 10 illustrates a cross-sectional view of a substrate during processing according to one or more embodiments; and

[0013] Fig.11 is a schematic top view of an exemplary multi-chamber processing system according to one or more embodiments. DETAILED DESCRIPTION

[0014] Before describing several exemplary embodiments of the present disclosure, it will be understood that the present disclosure is not limited to the details of construction or process steps set forth in the following description. The present disclosure is capable of other embodiments and of being practiced or carried out in various ways.

[0015] As used herein, the term "about" means approximately or nearly, and in the context of a stated numerical value or range means a variation of ±15% or less of the value. For example, values ​​that differ by ±14%, ±10%, ±5%, ±2%, ±1%, ±0.5%, or ±0.1% will meet the definition of about.

[0016] As used in this specification and the appended claims, the term "substrate" or "wafer" refers to a surface, or portion of a surface, on which a process is performed. As will also be understood by those skilled in the art, reference to a substrate may also refer to only a portion of a substrate unless the context clearly indicates otherwise. In addition, reference to depositing on a substrate may mean both a bare substrate and a substrate having one or more films or features deposited or formed thereon.

[0017] As used herein, "substrate" refers to any substrate or material surface formed on a substrate on which film processing is performed during a manufacturing process. For example, depending on the application, the substrate surface on which processing can be performed includes materials such as silicon, silicon oxide, strained silicon, silicon on insulator (SOI), carbon-doped silicon oxide, amorphous silicon, doped silicon, germanium, gallium arsenide, and any other material, such as metals, metal nitrides, metal alloys, and other conductive materials. Substrates include, but are not limited to, semiconductor wafers. The substrate may be exposed to a pretreatment process to polish, etch, reduce, oxidize, hydroxylate, anneal, and / or bake the substrate surface. In addition to processing directly on the surface of the substrate itself, in the present disclosure, as disclosed in more detail below, any of the disclosed film processing steps may also be performed on an underlying layer formed on the substrate, and the term "substrate surface" is intended to include such an underlying layer as indicated by the context. Thus, for example, where a film / layer or portion of a film / layer has been deposited onto a substrate surface, the exposed surface of the newly deposited film / layer becomes the substrate surface.

[0018] As used herein, the term "substrate surface" refers to any substrate surface on which a layer can be formed. The substrate surface may have one or more features formed therein, one or more layers formed thereon, and combinations thereof. The shape of the feature can be any suitable shape, including but not limited to peaks, trenches, holes, and vias (circular or polygonal). As used in this regard, the term "feature" refers to any intended surface irregularity. Suitable examples of features include but are not limited to trenches having a top, two sidewalls, and a bottom extending into the substrate, through holes having one or more sidewalls extending into the substrate to the bottom, and slot vias.

[0019] As used in this specification and the appended claims, the term "selective" refers to a process that operates on a first surface more than another, second surface. Such a process is described as operating "selectively" on the first surface relative to the second surface. The term "over" as used in this regard does not imply a physical orientation of one surface on top of another, but rather a relationship to the thermodynamic or kinetic properties of a chemical reaction on one surface relative to another.

[0020] The term "on" indicates that there is direct contact between components. The term "directly on" indicates that there is direct contact between components without intervening components.

[0021] As used in this specification and the appended claims, the terms "precursor," "reactant," "reactive gas," and the like are used interchangeably to refer to any gas species that can react with a substrate surface.

[0022] Embodiments of the present disclosure advantageously provide methods for selectively removing metallic material from a substrate surface. Some embodiments advantageously provide for removing metallic material from fields and sidewalls of features without removing metallic material from a bottom surface of a substrate. Further embodiments advantageously provide methods for depositing an etch stop layer comprising a flowable organic polymer. Additional embodiments advantageously provide methods for forming a metal gap fill in a bottom-up manner.

[0023] Embodiments of the present disclosure are described by way of drawings, which illustrate processes and substrates according to one or more embodiments of the present disclosure. The processes, schematics, and resulting substrates shown are merely illustrative of the disclosed processes, and those skilled in the art will recognize that the disclosed processes are not limited to the applications shown.

[0024] Referring to the drawings, the present disclosure is directed to a method 100 of selective metal removal. Figure 1 A process flow diagram of a selective metal removal method 100 is depicted in accordance with one or more embodiments of the present disclosure. Figure 2 A substrate 200 is depicted having a substrate surface having at least one feature formed therein. Figures 3 to 10 Depicted is a substrate during processing according to one or more embodiments of the present disclosure.

[0025] Figure 2 A substrate 200 is shown having a substrate surface 205. As noted above, a substrate surface refers to an exposed surface of a substrate on which a process may be performed. The substrate surface 205 has at least one feature 210 formed therein. Although only a single feature is illustrated in the drawings, those skilled in the art will recognize that multiple features will each be affected by the disclosed method in a similar manner.

[0026] At least one feature 210 has an opening 212 having an opening width W. Opening 212 is formed in a top surface 215 of substrate 200. Feature 210 also has one or more sidewalls 214 and extends a feature depth D from top surface 215 to bottom 216. Although straight vertical sidewalls are illustrated in the drawings, the disclosed methods may also be performed on sloped, irregular, or concave sidewalls.

[0027] although Figure 2214. Although the substrate 200 is shown as being composed of a single material 220, those skilled in the art will recognize that the top surface 215, the sidewalls 214, and the bottom 216 can each be composed of one or more similar or different materials. For example, the bottom of the sidewall 214 can be formed of a first material, while the upper portion of the same sidewall 214 can be composed of a second material. Similarly, a thin layer can be deposited on the top surface 215 without forming an appreciable part of the sidewall 214. In addition, the bottom 216 can be composed of a different material than the sidewall 214.

[0028] In some embodiments, the opening width W of the opening 212 is less than or equal to about 50 nm, less than or equal to about 30 nm, less than or equal to about 20 nm, less than or equal to about 10 nm, or less than or equal to about 7 nm. In some embodiments, the opening width W is in the range of about 8 nm to about 20 nm.

[0029] In some embodiments, feature 210 has a feature depth D greater than or equal to about 20 nm, greater than or equal to about 50 nm, greater than or equal to about 60 nm, greater than or equal to about 75 nm, or greater than or equal to about 90 nm. In some embodiments, opening width W is in the range of about 60 nm to about 100 nm.

[0030] In some embodiments, at least one feature 210 has a depth-to-width ratio (D / W) in a range from about 1 to about 20, or in a range from about 2 to about 15.

[0031] For simplicity, reference Figure 2 The portion of feature 210 shown in FIG. Figures 3 to 10 For example, Figure 3 The illustrated substrate 300 is referred to as having a bottom 216. To provide clarity to the description provided, component numbers for portions of feature 210 are not shown in FIG. Figures 3 to 10 Medium picture.

[0032] See also Figure 1 and Figures 3 to 10 In some embodiments, method 100 begins with optional operation 105 of pre-treating the substrate. The pre-treatment of operation 105 can be any suitable pre-treatment known to those skilled in the art. Suitable pre-treatments include, but are not limited to, pre-heating, cleaning, soaking, native oxide removal, or deposition of a contact layer (e.g., titanium silicide (TiSi)), or a capping layer (e.g., TiSiN). In some embodiments, a layer (such as titanium silicide or TiSiN) is deposited at operation 105.

[0033] After optional operation 105, Figure 33. An exemplary substrate 300 is illustrated in FIG. Substrate 300 includes a bottom formed by layer 310 and sidewalls and a top surface formed by layer 320. In some embodiments, layer 310 includes a conductive material and layer 320 includes a dielectric. One skilled in the art will recognize that the disclosed processes may be performed on different materials and / or the layers shown may be arranged in different ways.

[0034] The method 100 continues with loop 110. The loop 110 forms a layer of metal material 410 at the bottom 216 of the at least one feature 210 of the substrate 300. The loop 110 includes a series of operations, each of which is performed in sequence and can be repeated. Some operations are optional within each loop. A given optional operation can be performed periodically during each loop (every other, every five, or every one hundred cycles), performed as needed based on predetermined parameters, or even not performed at all.

[0035] like Figure 4 As shown, cycle 110 begins at optional operation 112. At 112, metal material 410 is deposited on substrate surface 205 of substrate 300. Metal material 410 has a bottom thickness on bottom 216 and a top thickness on top surface 215 and / or a sidewall thickness on sidewall 214.

[0036] The metal material may be deposited by any suitable method. In some embodiments, the metal material 410 may be deposited by physical vapor deposition (PVD). Figure 4 As shown, the sidewall thickness is less than the top thickness and the bottom thickness. In some embodiments, the top thickness is greater than the bottom thickness.

[0037] Those skilled in the art will recognize that the disclosed method may begin by forming the metal material 410 on the substrate surface 205 of the substrate 300. Thus, operation 112 is disclosed as optional.

[0038] Loop 100 continues to operation 114. Figure 5 As shown, at 114, a flowable polymer film 510 is formed within the feature 210 of the substrate 300. The polymer film 510 has a polymer depth less than or equal to the feature depth D. In other words, as a flowable film (described below), the polymer film is completely contained within the feature 210 and is not present on the top surface 215 of the substrate 300. In some embodiments, the polymer film has a depth in the range of about 1 nm to about 10 nm, or in the range of about 2 nm to about 5 nm.

[0039] In the disclosed methods, processing parameters and reactants may be selected to limit the conformality of the deposited material, which may allow the deposited material to better fill features on the substrate. A flowable material is a material that, under appropriate conditions, will flow by gravity to low points on the substrate surface and / or narrow the CD space of a trench or other feature by capillary action.

[0040] In some embodiments, forming a polymer film comprises exposing a surface to one or more monomers. In some embodiments, the monomer is essentially composed of a single difunctional monomer, and each functional group is different. In this way, one functional group of a monomer molecule will react with another functional group of a different monomer molecule. Those skilled in the art may identify this as an "A" polymer.

[0041] In some embodiments, the one or more monomers comprise or consist essentially of methacrylate, styrene, benzyl alcohol, benzyl chloride, or a derivative thereof. As used in this regard, a derivative of the base molecule may contain one or more groups comprising 1 to 10 carbon atoms. For example, in some embodiments, a methacrylate compound has the general formula:

[0042]

[0043] Wherein R is a group containing 1 to 10 carbon atoms and R' is a group containing 1 to 6 carbon atoms. As used in this regard, the group containing carbon atoms can be linear, branched, cyclic, saturated or unsaturated. The groups containing carbon atoms disclosed herein do not contain groups that are reactive in the chemical polymerization processes described herein.

[0044] In addition, the styrene derivative monomer may include a group on the benzene ring having 0 to 10 carbon atoms and an R' group on the vinyl group containing 1 to 6 carbon atoms. The benzyl alcohol derivative monomer or the benzyl chloride derivative monomer may include a group on the benzene ring having 0 to 10 carbon atoms and an R' group on the benzyl carbon containing 1 to 6 carbon atoms.

[0045] In some embodiments, the monomer consists essentially of two difunctional monomers, each functional group being identical. In this manner, the functional group of one monomer reacts with the functional group of the second monomer. Those skilled in the art may identify this as an "AB" polymer.

[0046] In some embodiments, the monomer comprises at least two amine, aldehyde, ketone, or alcohol groups. In some embodiments, the monomer has the general formula XR"-X, wherein X is selected from NH 2, NHR', O, OH, CHO, CR'O, COOH, or COOR', R' is a group containing 1 to 6 carbon atoms, and R" is a group containing 1 to 15 carbon atoms. In some embodiments, R' contains 1 to 4 carbon atoms. In some embodiments, R" is an ethylene or propylene group. In specific embodiments, the monomer contains terephthalic acid (TPA, C 6 H 4 (COOH) 2 ) and ethylenediamine (C 2 H 4 (NH 2 ) 2 ).

[0047] In some embodiments, the monomers include monofunctional monomers. When combined with the above embodiments, one skilled in the art may identify this as an "AC" or "ABC" polymer. Without being bound by theory, in these embodiments, it is believed that the monofunctional monomers act as terminal groups and limit any additional chain reactions.

[0048] In some embodiments, the monofunctional monomer comprises an amine, an aldehyde, a ketone, or an alcohol group. In some embodiments, the monofunctional monomer has the general formula RX, wherein R is a group comprising 1 to 10 carbon atoms, and X is selected from NH 2 , NHR', O, OH, or COOH, and R' is a group containing 1 to 6 carbon atoms.

[0049] As mentioned previously, the polymer film 510 is fluid. In order to control the "fluidity" of the resulting film, it has been found necessary to control the size of the resulting oligomers.

[0050] Thus, in some embodiments, the formation of the polymer film 510 is performed on a substrate maintained at a temperature in the range of 0° C. to 400° C. In some embodiments, the substrate is maintained at a temperature greater than or equal to about 0° C., greater than or equal to about 30° C., greater than or equal to about 50° C., greater than or equal to about 100° C., greater than or equal to about 200° C., or greater than or equal to about 300° C. In some embodiments, the substrate is maintained at a temperature less than or equal to about 400° C., less than or equal to about 300° C., less than or equal to about 200° C., less than or equal to about 100° C., less than or equal to about 50° C., or less than or equal to about 30° C.

[0051] Additionally, other processing parameters may be controlled during formation of polymer film 510. Examples of controllable parameters include, but are not limited to, processing chamber pressure, monomer selection, use of inert diluents or carrier gases, partial pressures of monomers, pulse sequences of monomers, and pulse periods to allow polymer material to flow.

[0052] Loop 110 continues to operation 116. Figure 6 As shown, at 116, at least a portion of the metal material 410 is selectively removed. The metal material 410 is removed from the top surface 215 without substantially affecting any material below the polymer film. As used in this context, a process that does not "substantially affect" a material layer does not result in any reduction in volume, thickness, or composition. Those skilled in the art will recognize that the polymer film 510 acts as an etch stop layer during the removal of a portion of the metal material 410.

[0053] In some embodiments, operation 116 also removes a portion of the metal material 410 from the sidewalls 214. In some embodiments, any metal material 410 present on the sidewalls 214 below the upper surface of the polymer film 510 may remain intact and not be removed.

[0054] In some embodiments, the selective removal of the metal material 410 is performed by exposing the substrate surface 205 of the substrate 300 to a NF 3 In some embodiments, the substrate is maintained at a temperature in the range of 80°C to 110°C.

[0055] In some embodiments, the selective removal of the metal material 410 is performed by the following sequence: oxidizing the metal material 410 and exposing the oxidized material to a metal halide to etch the oxidized material. In some embodiments, when the metal material comprises tungsten, the metal halide comprises WCl 5 .

[0056] Loop 110 continues to optional operation 118. Figure 7 As shown, at 118, the polymer film 510 is removed to expose the metal material 410 beneath the polymer film 510. In some embodiments, the removal of the polymer film 510 leaves a residue of the polymer film 510 on the surface of the metal material 410, illustrated as an X. In some embodiments, the removal of the polymer film 510 is complete and leaves no residue.

[0057] In some embodiments, the substrate surface 205 of the substrate 300 is exposed to H 2 The polymer film 510 is removed by plasma treatment. In some embodiments, the polymer film 510 is removed by exposure to O 2 In some embodiments, the polymer film 510 is removed by exposure to heat at high temperature. 2 environment to remove the polymer film 510.

[0058] Loop 110 continues to optional operation 119. Figure 8 As shown, at 119, residue X (if any) is cleaned from the surface of the metal material 410. The cleaning process can be any suitable process for cleaning the surface of the metal material. In some embodiments, the cleaning process does not oxidize the metal surface.

[0059] In some embodiments, at the end of cycle 110, the surface of metal material 410 does not contain any contaminants or residues of polymer layer 410. Specifically, in some embodiments, no carbon or oxygen residues are present on the surface of metal material 410. In some embodiments, when method 100 includes repeating cycle 110 (see below), no contaminants or residues are present between the amounts of metal material 410 deposited in subsequent cycles. In some embodiments, when method 100 includes depositing a second metal material 1010 (see below), no contaminants or residues are present between metal material 410 and second metal material 1010.

[0060] In some embodiments, this is achieved by a removal process due to operation 118 that leaves no residue or contaminants. In some embodiments, this is achieved by performing a cleaning process due to operation 119. In some embodiments, the monomer is selected so as not to contain any oxygen atoms that could oxidize the surface of the metal material 410 during the removal of the polymer layer 510.

[0061] The method 100 continues to a decision point 120. At point 120, the substrate is evaluated to determine whether the metal material 410 has reached a predetermined thickness or whether a predetermined number of cycles 110 have been performed. If the condition is met, the method 100 continues to operation 130. If the condition is not met, the method 100 returns to starting the cycle 110 with operation 112. In those embodiments, where the cycle 110 is repeated to form additional material, one skilled in the art will appreciate that the operation 112 is performed frequently to deposit the necessary additional metal material. In some embodiments, the predetermined thickness is in the range of about 2 nm to about 10 nm.

[0062] Method 100 continues to optional operation 130. Fig. 9 As shown, at 130, the metal material 410 is etched. In some embodiments, the metal material 410 is etched to remove portions of the metal material 410 that extend upwardly along the sidewalls 214. When being etched, the metal material 410 is also thinned at the bottom 216 of the feature 210. Thus, one skilled in the art will recognize that the metal material 410 may be deposited to a greater bottom thickness than desired in the final product to provide a sacrificial material that will be removed when the metal material is etched from the sidewalls 214.

[0063] Without being bound by theory, the inventors have discovered that removing the sidewall portions of metal material 410 simplifies the subsequent deposition of second metal material 1010 at operation 140. The uniformly flat surface provided by operation 130 allows second metal material 1010 to grow in a bottom-up manner without growing laterally from sidewalls 214.

[0064] Method 100 continues with optional operation 140. Fig.10 As shown, at 140, the second metal material 1010 is selectively deposited on the metal material 410. The deposition process is selective to the surface of the metal material 410 as compared to other substrate surface materials (e.g., layer 320). The selective deposition process provides a gap fill material including the second metal material 1010, which is formed in a bottom-up manner without being deposited laterally from the sidewalls 214. In some embodiments, the second metal material is deposited without forming any voids or gaps in the second metal material 1010.

[0065] In some embodiments, metal material 410 and second metal material 1010 comprise the same metal. In some embodiments, metal material 410 and second metal material 1010 comprise different metals. In some embodiments, the first metal material comprises or consists essentially of tungsten, molybdenum, or ruthenium.

[0066] The method may end after operation 140 or it may continue with optional post-processing at optional operation 150. The optional post-processing operation 150 may be, for example, a process for modifying film properties (e.g., annealing or plasma treatment), an additional film deposition process for growing additional films (e.g., additional ALD or CVD processes), or an additional etching process for forming a desired predetermined component architecture. In some embodiments, the optional post-processing operation 150 may be a process for modifying the properties of the deposited film. In some embodiments, the optional post-processing operation 150 includes annealing the substrate 300. In some embodiments, the annealing is performed at a temperature greater than or equal to about 300° C., greater than or equal to about 400° C., greater than or equal to about 500° C., greater than or equal to about 600° C., greater than or equal to about 700° C., greater than or equal to about 800° C., greater than or equal to about 900° C., or greater than or equal to about 1000° C. The annealing environment of some embodiments includes one or more of the following: an inert gas (e.g., molecular nitrogen (N 2 ), argon (Ar) or reducing gas (e.g., molecular hydrogen (H 2 ) or ammonia (NH 3 )) or an oxidizing agent, such as, but not limited to, oxygen (O 2 ), ozone (O 3 ), or peroxide. Annealing can be performed for any suitable length of time. In some embodiments, the substrate is annealed for a predetermined time in the range of about 15 seconds to about 90 minutes, or in the range of about 1 minute to about 60 minutes.

[0067] Fig.111 is a schematic top view of an exemplary multi-chamber processing system 1100 according to an embodiment of the present disclosure. The processing system 1100 generally includes a factory interface 1102, load lock chambers 1104, 1106, transfer chambers 1108, 1110 with corresponding transfer robots 1112, 1114, holding chambers 1116, 1118, and processing chambers 1120, 1122, 1124, 1126, 1128, 1130. As described in detail herein, wafers in the processing system 1100 can be processed in each chamber and transferred between each chamber without exposing the wafer to an ambient environment (e.g., an atmospheric ambient environment, such as may exist in a factory) external to the processing system 1100. For example, the wafer can be processed in each chamber and transferred between each chamber under a low pressure (e.g., less than or equal to about 300 Torr) or vacuum environment without breaking the low pressure or vacuum environment between each process performed on the wafer in the processing chamber 1100. Thus, the processing system 1100 may provide an integrated solution for some processing of a wafer.

[0068] Without being bound by theory, this integrated environment can aid in handling throughput and simplify processing schemes since a capping layer to prevent oxidation or metal is no longer required.In some embodiments, the disclosed methods are performed without breaking vacuum.

[0069] Examples of processing systems that may be suitably modified according to the teachings provided herein include or An integrated processing system or other suitable processing system is commercially available from Applied Materials, Inc., located in Santa Clara, Calif. It is contemplated that other processing systems, including those from other manufacturers, may be adapted to benefit from the aspects described herein.

[0070] exist Fig.11 In the illustrated example, the factory interface 1102 includes a docking station 1140 and a factory interface robot 1142 to facilitate the transfer of wafers. The docking station 1140 is configured to receive one or more front opening unified pods (FOUPs) 1144. In some examples, each factory interface robot 1142 generally includes a blade 1148 disposed on one end of the corresponding factory interface robot 1142, which is configured to transfer the wafer from the factory interface 1102 to the load lock chambers 1104, 1106.

[0071] The load lock chambers 1104, 1106 have respective ports 1150, 1152 coupled to the factory interface 1102 and respective ports 1154, 1156 coupled to the transfer chamber 1108. The transfer chamber 1108 further has respective ports 1158, 1160 coupled to the holding chambers 1116, 1118 and respective ports 1162, 1164 coupled to the processing chambers 1120, 1122. Similarly, the transfer chamber 1110 has respective ports 1166, 1168 coupled to the holding chambers 1116, 1118 and respective ports 1170, 1172, 1174, 1176 coupled to the processing chambers 1124, 1126, 1128, 1130. Ports 1154, 1156, 1158, 1160, 1162, 1164, 1166, 1168, 1170, 1172, 1174, 1176 may be, for example, slit valve openings with slit valves for transferring wafers therethrough by transfer robots 1112, 1114 and for providing a seal between the respective chambers to prevent transfer of gas between the respective chambers. In general, any port is open for transferring a wafer therethrough. Otherwise, the port is closed.

[0072] The load lock chambers 1104, 1106, the transfer chambers 1108, 1110, the holding chambers 1116, 1118, and the processing chambers 1120, 1122, 1124, 1126, 1128, 1130 may be fluidly coupled to a gas and pressure control system (not specifically shown). The gas and pressure control system may include one or more gas pumps (e.g., turbo pumps, cryopumps, roughing pumps), gas sources, various valves, and conduits fluidly coupled to the various chambers. In operation, the factory interface robot 1142 transfers a wafer from the FOUP 1144 through the port 1150 or 1152 to the load lock chamber 1104 or 1106. The gas and pressure control system then evacuates the load lock chamber 1104 or 1106. The gas and pressure control system further maintains the transfer chambers 1108, 1110 and the holding chambers 1116, 1118 to have an internal low pressure or vacuum environment (which may include an inert gas). Thus, evacuating the load lock chamber 1104 or 1106 facilitates transferring wafers between, for example, the atmospheric environment of the factory interface 1102 and the low pressure or vacuum environment of the transfer chamber 1108 .

[0073] While the wafer is in the evacuated load lock chamber 1104 or 1106, the transfer robot 1112 transfers the wafer from the load lock chamber 1104 or 1106 into the transfer chamber 1108 through the port 1154 or 1156. The transfer robot 1112 can then transfer the wafer to and / or between any of the processing chambers 1120, 1122 through the respective ports 1162, 1164 for processing, and to the holding chambers 1116, 1118 through the respective ports 1158, 1160 for holding awaiting further transfer. Similarly, the transfer robot 1114 is capable of accessing wafers in the holding chamber 1116 or 1118 through the port 1166 or 1168, and is capable of transferring wafers to any of the processing chambers 1124, 1126, 1128, 1130 and / or between any of these processing chambers for processing through the corresponding ports 1170, 1172, 1174, 1176, and transferring to the holding chamber 1116, 1118 for holding awaiting further transfer through the corresponding ports 1166, 1168. Transferring and holding wafers within and among the various chambers may be in a low pressure or vacuum environment provided by a gas and pressure control system.

[0074] Processing chambers 1120, 1122, 1124, 1126, 1128, 1130 may be any suitable chamber for processing a wafer according to method 100. In some embodiments, processing chamber 1120 may be capable of performing a pre-treatment process, processing chambers 1122, 1124 may be capable of performing a deposition process, processing chambers 1126, 1128 may be capable of performing an etching process, and processing chamber 1130 may be capable of performing a cleaning process. Processing chamber 1120 may be a SiCoNi® wafer available from Applied Materials, Inc. of Santa Clara, California. TM The processing chambers 1126, 1128 may be Selectra, each available from Applied Materials, Inc., Santa Clara, California. TM Etch chamber, MCxT chamber or Volta chamber.

[0075] A system controller 1190 is coupled to the processing system 1100 for controlling the processing system 1100 or components thereof. For example, the system controller 1190 may control the operation of the processing system 1100 using direct control of the chambers 1104, 1106, 1108, 1116, 1118, 1110, 1120, 1122, 1124, 1126, 1128, 1130 of the processing system 1100 or by controlling controllers associated with the chambers 1104, 1106, 1108, 1116, 1118, 1110, 1120, 1122, 1124, 1126, 1128, 1130. In operation, the system controller 1190 enables data collection and feedback from the respective chambers to coordinate the performance of the processing system 1100.

[0076] The system controller 1190 generally includes a central processing unit (CPU) 1192, a memory 1194, and support circuits 1196. The CPU 1192 may be one of any form of general purpose processor that may be used in an industrial environment. The memory 1194 or non-transitory computer readable medium is accessible by the CPU 1192 and may be one or more memories such as random-access memory (RAM), read only memory (ROM), a floppy disk, a hard disk, or any other form of digital storage (local or remote). The support circuits 1196 are coupled to the CPU 1192 and may include caches, clock circuits, input / output subsystems, power supplies, and the like. The various methods disclosed herein may be implemented by the CPU 1192 executing computer instruction code (e.g., as a software routine) stored in the memory 1194 (or in the memory of a particular processing chamber) generally under the control of the CPU 1192. When the computer instruction code is executed by the CPU 1192 , the CPU 1192 controls the chamber to perform processes according to various methods.

[0077] Other processing systems can have other configurations. For example, more or fewer processing chambers can be coupled to the transfer device. In the example shown, the transfer device includes transfer chambers 1108, 1110 and holding chambers 1116, 1118. In other examples, more or fewer transfer chambers (e.g., one transfer chamber) and / or more or fewer holding chambers (e.g., no holding chamber) can be implemented as a transfer device in a processing system.

[0078] The process may be generally stored as a software routine in the memory of the system controller 1190, which, when executed by the processor, causes the processing chamber to perform the process of the present disclosure. The software routine may also be stored and / or executed by a second processor (not shown) that is remote from the hardware controlled by the processor. Some or all of the methods of the present disclosure may also be performed in hardware. Thus, the process may be implemented in software and executed in hardware using a computer system, as, for example, a special application integrated circuit or other type of hardware implementation, or as a combination of software and hardware. When executed by the processor, the software routine converts a general-purpose computer into a special-purpose computer (controller) that controls the chamber operation so that the process is performed.

[0079] Embodiments of the present disclosure relate to a non-transitory computer-readable medium. In one or more embodiments, the non-transitory computer-readable medium includes instructions that, when executed by a controller of a processing chamber, cause the processing chamber to perform the operations of any of the methods described herein (e.g., method 100). In one or more embodiments, the controller causes the processing chamber to perform the operations of method 100. In one or more embodiments, the controller causes the processing chamber to perform an operation of forming a polymer film on a substrate surface (operation 114). In one or more embodiments, the controller causes the processing chamber to perform an operation of removing a metal material (operation 116).

[0080] For ease of description, spatially relative terms (such as "below," "under," "lower," "above," "upper," and the like) may be used herein to describe the relationship of one component or feature to another component or feature shown in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of components in use or operation, in addition to the orientations depicted in the figures. For example, if the components in the figures are flipped, components described as "below" or "beneath" other components or features would be oriented "above" the other components or features. Thus, the exemplary term "below" can include both below and above orientations. Components may be otherwise oriented (rotated 90 degrees or in other orientations) and the spatially relative descriptors used herein interpreted accordingly.

[0081] Unless otherwise indicated herein or clearly denied by context, the use of the terms "a" and "an" and "the" and similar references in the context of describing the materials and methods discussed herein (particularly in the context of the following claims) will be understood to cover the singular and the plural. Unless otherwise indicated herein, the recording of the value range herein is merely intended to be used as a shorthand method of independently referring to each individual value falling into the range, and each individual value is incorporated into the specification as if it were independently recorded herein. Unless otherwise indicated herein or clearly denied by context, all methods described herein can be performed in any suitable order. The use of any and all examples, or exemplary language (e.g., "such as") provided herein is intended only to better illustrate the materials and methods, and does not confer limitations on the scope unless otherwise claimed. The language in the specification should not be interpreted as indicating that any unclaimed element is essential to practicing the disclosed materials and methods.

[0082] References throughout this specification to "one embodiment," "certain embodiments," "one or more embodiments," or "an embodiment" mean that a particular feature, structure, material, or characteristic described in connection with the embodiment is included in at least one embodiment of the present disclosure. Thus, the appearance of phrases such as "in one or more embodiments," "certain embodiments," "in an embodiment," or "in an embodiment" in various places throughout this specification do not necessarily refer to the same embodiment of the present disclosure. In one or more embodiments, the particular features, structures, materials, or characteristics are combined in any suitable manner.

[0083] Although the disclosure herein has been described with reference to specific embodiments, it will be understood that these embodiments are merely illustrative of the principles and applications of the disclosure. It will be apparent to those skilled in the art that various modifications and variations may be made to the methods and apparatus of the disclosure without departing from the spirit and scope of the disclosure. Therefore, the disclosure is intended to include modifications and variations within the scope of the appended claims and their equivalents.

Claims

1. A method for selective metal removal, the method comprising the following steps: forming a flowable polymer film on a surface of a substrate having at least one feature formed therein, the at least one feature having an opening with an opening width at a top surface, at least one sidewall, and a bottom, the at least one feature extending a feature depth from the top surface to the bottom, the flowable polymer film being formed within the at least one feature and having a polymer depth less than or equal to the feature depth; and At least a portion of the metallic material is selectively removed from the top surface without substantially affecting any material beneath the polymer film.

2. The method of claim 1, wherein the step of forming a polymer film comprises the step of exposing the substrate surface to one or more monomers.

3. The method of claim 2, wherein the monomer consists essentially of a single, difunctional monomer.

4. The method of claim 2, wherein the monomer consists essentially of two difunctional monomers.

5. The method of claim 2, wherein the monomer comprises a monofunctional terminal monomer.

6. The method of claim 1, wherein the step of selectively removing the metal material is performed by exposing the substrate surface to NF3 radicals.

7. The method of claim 1, further comprising the steps of: The metallic material is deposited on the substrate surface prior to forming the polymer film, the metallic material having a top thickness on the top surface and a bottom thickness on the bottom of the at least one feature.

8. The method of claim 7, wherein the metal material is deposited by physical vapor deposition (PVD) and has a sidewall thickness that is less than the top thickness and the bottom thickness.

9. The method of claim 1, further comprising the steps of: The polymer film is removed to expose the metal layer beneath the polymer film.

10. The method of claim 9, wherein the polymer film is removed by exposing the substrate surface to H2 plasma treatment.

11. The method of claim 9, further comprising the steps of: A second metal material is selectively deposited on the metal layer.

12. The method of claim 1, further comprising the steps of: depositing the metallic material on the substrate surface prior to forming the polymer film, the metallic material having a top thickness on the top surface and a bottom thickness on the bottom of the at least one feature; removing the polymer film to expose the metal material beneath the polymer film; as well as The cycle of depositing the metal material, forming the polymer film, selectively removing the metal material, and removing the polymer film is repeated to form a predetermined thickness of the metal material on the bottom of the at least one feature.

13. The method of claim 12, wherein the predetermined thickness is in a range of about 2 nm to about 10 nm.

14. The method of claim 12, wherein substantially no carbon or oxygen residues are present between layers of the metallic material at the bottom of the at least one feature.

15. The method of claim 1, wherein the opening width is in a range of about 8 nm to about 20 nm.

16. The method of claim 1, wherein the feature depth is in the range of about 60 nm to about 100 nm.

17. The method of claim 1, wherein a ratio of the feature depth to the opening width is in a range of about 2 to about 15.

18. The method of claim 1, wherein the polymer depth is in the range of about 1 nm to about 10 nm.

19. The method of claim 1, wherein the metal material comprises one or more of tungsten, molybdenum, or ruthenium.

20. A method for selective tungsten removal, the method comprising the following steps: depositing a tungsten material on a surface of a substrate having at least one feature formed therein, the at least one feature having an opening with an opening width at a top surface, at least one sidewall, and a bottom, the at least one feature extending a feature depth from the top surface to the bottom; forming a flowable polymer film within the at least one feature, the flowable polymer film formed having a polymer depth less than or equal to a depth of the feature; selectively removing at least a portion of the tungsten material from the top surface without substantially affecting the tungsten material beneath the polymer film; removing the polymer film to expose the tungsten material beneath the polymer film; etching the tungsten material from the at least one sidewall; as well as A second metal material is selectively deposited on the tungsten material.

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