Selective ETCH of titanium-containing materials

Abstract

Exemplary semiconductor processing methods may include providing an oxygen-containing precursor to a remote plasma region of a semiconductor processing chamber. The methods may include forming plasma effluents of the oxygen-containing precursor in the remote plasma region. The methods may include providing the plasma effluents of the oxygen-containing precursor to a processing region. A substrate may be housed within the processing region. The substrate may define an exposed region of a titanium-and-nitrogen containing material and an exposed region of one or more silicon-containing materials. The methods may include providing a fluorine-containing precursor to the processing region. The fluorine-containing precursor may be provided plasma-free. The methods may include contacting the substrate with the plasma effluents of the oxygen-containing precursor and the fluorine-containing precursor. The contacting may etch at least a portion of the exposed region of a titanium-and-nitrogen containing material.

Description

PATENTKTS No.: 080042-44025719W001-1483249SELECTIVE ETCH OF TITANIUM-CONTAINING MATERIALS TECHNICAL FIELD

[0001] The present technology7relates to semiconductor processes and equipment. More specifically, the present technology7relates to selectively etching titanium-containing materials.BACKGROUND

[0002] Integrated circuits are made possible by processes which produce intricately patterned material layers on substrate surfaces. Producing patterned material on a substrate requires controlled methods for removal of exposed material. Chemical etching is used for a variety of purposes including transferring a pattern in photoresist into underlying layers, thinning layers, or thinning lateral dimensions of features already present on the surface. Often it is desirable to have an etch process that etches one material faster than another facilitating, for example, a pattern transfer process. Such an etch process is said to be selective to the first material. As a result of the diversity7of materials, circuits, and processes, etch processes have been developed with a selectivity towards a variety of materials.

[0003] Etch processes may be termed wet or dry7based on the materials used in the process. For example, a wet etch may preferentially remove some oxide dielectrics over other dielectrics and materials. However, wet processes may have difficulty penetrating some constrained trenches and also may sometimes deform the remaining material. Dry7etches produced in local plasmas formed within the substrate processing region can penetrate more constrained trenches and exhibit less deformation of delicate remaining structures. However, local plasmas may damage the substrate through the production of electric arcs as they discharge.

[0004] Thus, there is a need for improved systems and methods that can be used to produce high quality devices and structures. These and other needs are addressed by the present technology.SUMMARY

[0005] Exemplary semiconductor processing methods may include providing an oxygencontaining precursor to a remote plasma region of a semiconductor processing chamber. The methods may include forming plasma effluents of the oxygen-containing precursor in the remote plasma region of the semiconductor processing chamber. The methods may include providing the plasma effluents of the oxy gen-containing precursor to a processing region of the semiconductor processing chamber. A substrate may be housed within the processing region. The substrate may define an exposed region of a titanium-and-nitrogen containing material and an exposed region of one or more silicon-containing materials. The methods may include providing a fluorine-containing precursor to the processing region of the semiconductor processing chamber. The fluorine-containing precursor may be provided plasma-free. The methods may include contacting the substrate with the plasma effluents of the oxygen-containing precursor and the fluorine-containing precursor. The contacting may etch at least a portion of the exposed region of a titanium-and-nitrogen containing material.

[0006] In embodiments, the oxygen-containing precursor may be or include atomic oxygen (O), diatomic oxygen (O2), ozone (Os), nitrous oxide (N2O), nitrogen dioxide (NO2), water or steam (H2O). or hydrogen peroxide (H2O2). The remote plasma effluents of the oxygencontaining precursor may be formed at a plasma power of between about 50 W and about 600 W. The one or more silicon-containing materials may be or include polysilicon, a silicon-and-oxygen-containing material, or a silicon-and-nitrogen-containing material. The fluorine-containing precursor may be or include tungsten hexafluoride (WFe), nitrogen trifluoride (NF3), or carbon tetrafluoride (CF4). A flow rate of the oxygen-containing precursor may be greater than or about a flow rate of the fluorine-containing precursor. The processing region may be maintained plasma-free while contacting the substrate with the remote plasma effluents of the oxygen-containing precursor and the fluorine-containing precursor.Contacting the substrate with the remote plasma effluents of the oxygen-containing precursor may at least partially oxidize the exposed region of one or more silicon-containing materials. The remote plasma effluents of the oxy gen-containing precursor may at least partially excite the fluorine-containing precursor. Contacting the substrate with the fluorine-containing precursor may at least partially convert the exposed region of the titanium-and-nitrogen containing material to a titanium-and-fluorine containing material.

[0007] Some embodiments of the present technology may encompass semiconductor processing methods. The methods may include providing an oxy gen-containing precursor and a fluorine-containing precursor to a processing region of a semiconductor processing chamber. A substrate may be housed within the processing region. The substrate may define an exposed region of a titanium-and-nitrogen containing material and an exposed region of one or more silicon-containing materials. The methods may include forming plasma effluents of the oxy gen-containing precursor and / or the fluorine-containing precursor. The methods may include contacting the substrate with the plasma effluents of the oxy gen-containing precursor and / or the fluorine-containing precursor. The contacting may etch at least a portion of the exposed region of a titanium-and-nitrogen containing material.

[0008] In embodiments, a flow rate ratio of the fluorine-containing precursor relative to the oxygen-containing precursor may be between about 1 : 500 and about 500:1. A temperature within the processing region may be maintained at greater than or about 100 °C. A pressure within the processing region may be maintained at less than or about 100 Torr. Contacting the substrate with the plasma effluents of the oxygen-containing precursor and / or the fluorine-containing precursor may etch the portion of the titanium-and-nitrogen containing material at an etch rate of greater than or about 15 A / min. Contacting the substrate with the plasma effluents of the oxygen-containing precursor and / or the fluorine-containing precursor may etch the titanium-and-nitrogen containing material relative to the one or more silicon-containing materials at a selectivity of greater than or about 10: 1.

[0009] Some embodiments of the present technology may encompass semiconductor processing methods. The methods may include providing an oxy gen-containing precursor to a remote plasma region of a semiconductor processing chamber. The methods may include forming remote plasma effluents of the oxy gen-containing precursor in the remote plasma region of the semiconductor processing chamber. The methods may include providing the remote plasma effluents of the oxygen-containing precursor to a processing region of the semiconductor processing chamber. A substrate may be housed within the processing region. The substrate may define an exposed region of a titanium-and-nitrogen containing material and an exposed region of one or more silicon-containing materials. The methods may include providing a fluorine-containing precursor to the processing region of the semiconductor processing chamber. The fluorine-containing precursor may be provided plasma-free. The methods may include contacting the substrate with the remote plasma effluents of the oxy gen-containing precursor and the fluorine-containing precursor. Thecontacting may etch at least a portion of the exposed region of a titanium-and-nitrogen containing material. A temperature within the processing region may be maintained at greater than or about 200 °C. A pressure within the processing region may be maintained at greater than or about 1 Torr.

[0010] In embodiments, the oxygen-containing precursor may be or include diatomic oxy gen (O2). The fluorine-containing precursor may be or include tungsten hexafluoride (WFe). The methods may include providing one or more inert gases with the oxygencontaining precursor and / or the fluorine-containing precursor. Contacting the substrate with the remote plasma effluents of the oxygen-containing precursor and the fluorine-containing precursor may etch the portion of the titanium-and-nitrogen containing material at an etch rate of greater than or about 25 A / min.

[0011] Such technology may provide numerous benefits over conventional systems and techniques. For example, the processes may allow dry etching to be performed that may protect features of the substrate. Additionally, the processes may selectively remove titanium-containing films relative to other exposed materials on the substrate. These and other embodiments, along with many of their advantages and features, are described in more detail in conjunction with the below description and attached figures.BRIEF DESCRIPTION OF THE DRAWINGS

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

[0013] FIG. 1 shows a top plan view of one embodiment of an exemplary processing system according to some embodiments of the present technology.

[0014] FIG. 2A shows a schematic cross-sectional view of an exemplary processing chamber according to some embodiments of the present technology.

[0015] FIG. 2B shows a detailed view of a portion of the processing chamber illustrated in FIG. 2A according to some embodiments of the present technology.

[0016] FIG. 3 shows a bottom plan view of an exemplary7showerhead according to some embodiments of the present technology.

[0017] FIG. 4 shows exemplary operations in a method according to some embodiments of the present technology.

[0018] FIGS. 5A-5B show schematic cross-sectional views of materials etched according to some embodiments of the present technology.

[0019] Several of the figures are included as schematics. It is to be understood that the figures are for illustrative purposes, and are not to be considered of scale unless specifically stated to be of scale. Additionally, as schematics, the figures are provided to aid comprehension and may not include all aspects or information compared to realistic representations, and may include additional or exaggerated material for illustrative purposes.

[0020] In the appended figures, similar components and / or features may have the same reference label. Further, various components of the same ty pe may be distinguished by following the reference label by a letter that distinguishes among the similar components. If only the first reference label is used in the specification, the description is applicable to any one of the similar components having the same first reference label irrespective of the letter.DETAILED DESCRIPTION

[0021] Diluted acids may be used in many different semiconductor processes for cleaning substrates and removing materials from those substrates. For example, diluted hydrofluoric acid (“dHF”) can be an effective etchant for silicon oxide, aluminum oxide, titanium oxide, and other materials, and may be used to remove these materials from substrate surfaces. After the etching or cleaning operation is complete, the acid may be dried from the wafer or substrate surface. Using dHF may be termed a “wet” etch where the diluent is often water. Additional etching processes may be used that utilize precursors delivered to the substrate. For example, plasma enhanced processes may also selectively etch materials by enhancing precursors through the plasma to perform a dry etch.

[0022] Although wet etchants using aqueous solutions or water-based processes may operate effectively for certain substrate structures, the water may pose challenges in a variety of conditions. For example, utilizing water during etch processes may cause issues when disposed on substrates including metal materials. For example, certain later fabrication processes, such as recessing gaps, removing oxide dielectric, or other processes to remove oxygen-containing materials, may be performed after an amount of metallization has beenformed on a substrate. If water is utilized in some fashion during the etching, an electrolyte may be produced, which when contacting the metal material, may cause galvanic corrosion to occur between dissimilar metals, and the metal may be corroded or displaced in various processes. In addition, because of the surface tension of the water diluent, pattern deformation and collapse may occur with minute structures. The water-based material may also be incapable of penetrating some high aspect ratio features due to surface tension effects. Plasma etching may overcome the issues associated with water-based etching, although additional issues may occur. For example, a reactive ion etch process may expose the metal to ion activity, which through bombardment can damage the structure, and affect electrical characteristics.

[0023] The present technology overcomes these issues by performing a dry etch process that may passivate a number of materials relative to a material to be etched, and in some embodiments a process may be plasma free during the etching. By utilizing particular precursors that may facilitate halogen dissociation to provide etchant materials, an etch process may be performed that may protect the surrounding structures. Additionally, the materials and conditions used may allow improved etching relative to conventional techniques.

[0024] Although the remaining disclosure will routinely identify specific etching processes utilizing the disclosed technology, it will be readily understood that the systems and methods are equally applicable to deposition and cleaning processes as may occur in the described chambers, as well as other etching technology and other etching that may be performed with a variety of exposed materials that may be maintained or substantially maintained.Accordingly, the technology should not be considered to be so limited as for use with the exemplary etching processes or chambers alone. Moreover, although an exemplary chamber is described to provide foundation for the present technology, it is to be understood that the present technology can be applied to virtually any semiconductor processing chamber that may allow the operations described.

[0025] FIG. 1 shows a top plan view of one embodiment of a processing system 100 of deposition, etching, baking, and curing chambers according to embodiments. In the figure, a pair of front opening unified pods (FOUPs) 102 supply substrates of a variety of sizes that are received by robotic arms 104 and placed into a low pressure holding area 106 before being placed into one of the substrate processing chambers 108a-f, positioned in tandem sections109a-c. A second robotic arm 110 may be used to transport the substrate wafers from the holding area 106 to the substrate processing chambers 108a-f and back. Each substrate processing chamber 108a-f, can be outfitted to perform a number of substrate processing operations including the dry etch processes described herein in addition to cyclical layer deposition (CLD), atomic layer deposition (ALD), chemical vapor deposition (CVD), physical vapor deposition (PVD), etch, pre-clean, degas, orientation, and other substrate processes.

[0026] The substrate processing chambers 108a-f may include one or more system components for depositing, annealing, curing, and / or etching a dielectric film on the substrate wafer. In one configuration, two pairs of the processing chambers, e.g., 108c-d and 108e-f, may be used to deposit dielectric material on the substrate, and the third pair of processing chambers, e.g.. 108a-b, may be used to etch the deposited dielectric. In another configuration, all three pairs of chambers, e.g., 108a-f, may be configured to etch a dielectric film on the substrate. Any one or more of the processes described may be carried out in chamber(s) separated from the fabrication system shown in different embodiments. It will be appreciated that additional configurations of deposition, etching, annealing, and curing chambers for dielectric films are contemplated by system 100.

[0027] FIG. 2A shows a cross-sectional view of an exemplary process chamber system 200 with partitioned plasma generation regions within the processing chamber. During film etching, e.g., titanium nitride, tantalum nitride, tungsten, silicon, poly silicon, silicon oxide, silicon nitride, silicon oxynitride, silicon oxy carbide, etc., a process gas may be flowed into the first plasma region 215 through a gas inlet assembly 205. A remote plasma system (RPS) 201 may optionally be included in the system, and may process a first gas which then travels through gas inlet assembly 205. The inlet assembly 205 may include two or more distinct gas supply channels where the second channel (not shown) may bypass the RPS 201, if included.

[0028] A cooling plate 203, faceplate 217, ion suppressor 223, showerhead 225, and a pedestal 265 or substrate support, having a substrate 255 disposed thereon, are shown and may each be included according to embodiments. The pedestal 265 may have a heat exchange channel through which a heat exchange fluid flows to control the temperature of the substrate, which may be operated to heat and / or cool the substrate or wafer during processing operations. The wafer support platter of the pedestal 265. which may include aluminum, ceramic, or a combination thereof, may also be resistively heated in order to achieverelatively high temperatures, such as from up to or about 100° C to above or about 1100° C, using an embedded resistive heater element.

[0029] The faceplate 217 may be pyramidal, conical, or of another similar structure with a narrow top portion expanding to a wide bottom portion. The faceplate 217 may additionally be flat as shown and include a plurality7of through-channels used to distribute process gases. Plasma generating gases and / or plasma excited species, depending on use of the RPS 201, may pass through a plurality of holes, shown in FIG. 2B, in faceplate 217 for a more uniform delivery into the first plasma region 215.

[0030] Exemplary configurations may include having the gas inlet assembly 205 open into a gas supply region 258 partitioned from the first plasma region 215 by faceplate 217 so that the gases / species flow through the holes in the faceplate 217 into the first plasma region 215. Structural and operational features may be selected to prevent significant backflow of plasma from the first plasma region 215 back into the supply region 258, gas inlet assembly 205, and fluid supply system 210. The faceplate 217, or a conductive top portion of the chamber, and showerhead 225 are show n with an insulating ring 220 located betw een the features, which allows an AC potential to be applied to the faceplate 217 relative to showerhead 225 and / or ion suppressor 223. The insulating ring 220 may be positioned between the faceplate 217 and the showerhead 225 and / or ion suppressor 223 enabling a capacitively coupled plasma (CCP) to be formed in the first plasma region. A baffle (not show n) may additionally be located in the first plasma region 215, or otherwise coupled with gas inlet assembly 205, to affect the flow of fluid into the region through gas inlet assembly 205.

[0031] The ion suppressor 223 may comprise a plate or other geometry that defines a plurality of apertures throughout the structure that are configured to suppress the migration of ionically-charged species out of the first plasma region 215 while allowing uncharged neutral or radical species to pass through the ion suppressor 223 into an activated gas delivery region between the suppressor and the showerhead. In embodiments, the ion suppressor 223 may comprise a perforated plate with a variety of aperture configurations. These uncharged species may include highly reactive species that are transported with less reactive carrier gas through the apertures. As noted above, the migration of ionic species through the holes may¬ be reduced, and in some instances completely suppressed. Controlling the amount of ionic species passing through the ion suppressor 223 may advantageously provide increased control over the gas mixture brought into contact with the underlying wafer substrate, whichin turn may increase control of the deposition and / or etch characteristics of the gas mixture. For example, adjustments in the ion concentration of the gas mixture can significantly alter its etch selectivity. In alternative embodiments in which deposition is performed, it can also shift the balance of conformal-to-flowable style depositions for dielectric materials.

[0032] The plurality of apertures in the ion suppressor 223 may be configured to control the passage of the activated gas, i.e.. the ionic, radical, and / or neutral species, through the ion suppressor 223. For example, the aspect ratio of the holes, or the hole diameter to length, and / or the geometry of the holes may be controlled so that the flow of ionically-charged species in the activated gas passing through the ion suppressor 223 is reduced. The holes in the ion suppressor 223 may include a tapered portion that faces the plasma excitation region 215, and a cylindrical portion that faces the showerhead 225. The cylindrical portion may be shaped and dimensioned to control the flow of ionic species passing to the showerhead 225. An adjustable electrical bias may also be applied to the ion suppressor 223 as an additional means to control the flow of ionic species through the suppressor.

[0033] The ion suppressor 223 may function to reduce or eliminate the amount of ionically charged species traveling from the plasma generation region to the substrate. Uncharged neutral and radical species may still pass through the openings in the ion suppressor to react with the substrate. It should be noted that the complete elimination of ionically charged species in the reaction region surrounding the substrate may not be performed in embodiments. In certain instances, ionic species are intended to reach the substrate in order to perform the etch and / or deposition process. In these instances, the ion suppressor may help to control the concentration of ionic species in the reaction region at a level that assists the process.

[0034] Showerhead 225 in combination with ion suppressor 223 may allow a plasma present in first plasma region 215 to avoid directly exciting gases in substrate processing region 233. while still allowing excited species to travel from chamber plasma region 215 into substrate processing region 233. In this way, the chamber may be configured to prevent the plasma from contacting a substrate 255 being etched. This may advantageously protect a variety of intricate structures and films patterned on the substrate, which may be damaged, dislocated, or otherwise warped if directly contacted by a generated plasma. Additionally, when plasma is allowed to contact the substrate or approach the substrate level, the rate at which oxide species etch may increase. Accordingly, if an exposed region of material isoxide, this material may be further protected by maintaining the plasma remotely from the substrate.

[0035] The processing system may further include a power supply 240 electrically coupled with the processing chamber to provide electric power to the faceplate 217, ion suppressor 223, showerhead 225, and / or pedestal 265 to generate a plasma in the first plasma region 215 or processing region 233. The power supply may be configured to deliver an adjustable amount of power to the chamber depending on the process performed. Such a configuration may allow for a tunable plasma to be used in the processes being performed. Unlike a remote plasma unit, which is often presented with on or off functionality, a tunable plasma may be configured to deliver a specific amount of power to the plasma region 215. This in turn may allow development of particular plasma characteristics such that precursors may be dissociated in specific ways to enhance the etching profiles produced by these precursors.

[0036] A plasma may be ignited either in chamber plasma region 215 above showerhead 225 or substrate processing region 233 below showerhead 225. Plasma may be present in chamber plasma region 215 to produce the radical precursors from an inflow of, for example, a fluorine-containing precursor or other precursor. An AC voltage typically in the radio frequency (RF) range may be applied between the conductive top portion of the processing chamber, such as faceplate 217, and showerhead 225 and / or ion suppressor 223 to ignite a plasma in chamber plasma region 215 during deposition. An RF power supply may generate a high RF frequency of 13.56 MHz but may also generate other frequencies alone or in combination with the 13.56 MHz frequency.

[0037] FIG. 2B shows a detailed view 253 of the features affecting the processing gas distribution through faceplate 217. As shown in FIGS. 2A and 2B, faceplate 217, cooling plate 203, and gas inlet assembly 205 intersect to define a gas supply region 258 into which process gases may be delivered from gas inlet 205. The gases may fill the gas supply region 258 and flow to first plasma region 215 through apertures 259 in faceplate 217. The apertures 259 may be configured to direct flow in a substantially unidirectional manner such that process gases may flow into processing region 233, but may be partially or fully prevented from backflow' into the gas supply region 258 after traversing the faceplate 217.

[0038] The gas distribution assemblies such as showerhead 225 for use in the processing chamber section 200 may be referred to as dual channel showerheads (DCSH) and are additionally detailed in the embodiments described in FIG. 3. The dual channel showerheadmay provide for etching processes that allow for separation of etchants outside of the processing region 233 to provide limited interaction with chamber components and each other prior to being delivered into the processing region.

[0039] The showerhead 225 may comprise an upper plate 214 and a lower plate 216. The plates may be coupled with one another to define a volume 218 between the plates. The coupling of the plates may be so as to provide first fluid channels 219 through the upper and lower plates, and second fluid channels 221 through the lower plate 216. The formed channels may be configured to provide fluid access from the volume 218 through the lower plate 216 via second fluid channels 221 alone, and the first fluid channels 219 may be fluidly isolated from the volume 218 between the plates and the second fluid channels 221. The volume 218 may be fluidly accessible through a side of the showerhead 225.

[0040] FIG.3 is a bottom view of a showerhead 325 for use with a processing chamber according to embodiments. Showerhead 325 may correspond with the showerhead 225 shown in FIG. 2A. Through-holes 365, which show? a view of first fluid channels 219, may have a plurality of shapes and configurations in order to control and affect the flow of precursors through the showerhead 225. Small holes 375, which show a view of second fluid channels 221, may be distributed substantially evenly over the surface of the showerhead, even amongst the through-holes 365, and may help to provide more even mixing of the precursors as they exit the showerhead than other configurations.

[0041] The chamber discussed previously may be used in performing exemplary methods including etching methods. Turning to FIG. 4, exemplary’ operations in a method 400 according to embodiments of the present technology are illustrated. Method 400 may include one or more operations prior to the initiation of the method, including front end processing, deposition, gate formation, etching, polishing, cleaning, or any other operations that may be performed prior to the described operations. The method may include a number of optional operations, which may or may not be specifically associated with some embodiments of methods according to the present technology. For example, many of the operations are described in order to provide a broader scope of the processes performed, but are not critical to the technology, or may be performed by alternative methodology as will be discussed further below. Method 400 may describe operations shown schematically in FIGS. 5A-5B, the illustrations of which will be described in conjunction with the operations of method 400. It is to be understood that the figures illustrate only partial schematic views, and a substratemay contain any number of additional materials and features having a variety of characteristics and aspects as illustrated in the figures.

[0042] Method 400 may or may not involve optional operations to develop the semiconductor structure to a particular fabrication operation. It is to be understood that method 400 may be performed on any number of semiconductor structures or substrates 505, as illustrated in FIG. 5A, including exemplary structures on which a titanium nitride removal operation may be performed. Exemplary semiconductor structures may include a trench, via, or other recessed features that may include one or more exposed materials. For example, an exemplary substrate may contain silicon or some other semiconductor substrate material as well as one or more dielectric materials through which a recess, trench, via, or isolation structure may be formed. Exposed materials at any time during the etch process may be or include metal materials such as a gate, a dielectric material, a contact material, a transistor material, or any other material that may be used in semiconductor processes. In embodiments, an exemplar.' structure 500 may include a first dielectric material 510. The first dielectric material may define the recess, trench, via, or isolation structure, which may generally be referred to as a feature 512. previously discussed. A liner material 515 may conformally line the feature 512. The liner material 515, like first dielectric material 510, may be a dielectric material. One or more regions of a titanium-containing material 520 may be disposed within the feature 512 and, in embodiments, may be separated by a second dielectric material. The titanium-containing material 520 may be, for example, a titanium-and-nitrogen-containing material. Each of the first dielectric material 510. the liner material 515, and the second dielectric material 525 may be the same or different dielectric materials. For example, the first dielectric material 510, the liner material 515, and the second dielectric material 525 may be silicon-containing materials, such as epitaxial silicon, polysilicon, a silicon-and-oxy gen-containing material, a silicon-and-nitrogen-containing material, or any other silicon-containing dielectric material. In an exemplary embodiment, the first dielectric material 510 may be epitaxial silicon, the liner material 515 may be silicon-and-oxygen-containing material, and the second dielectric material 525 may be poly silicon. As illustrated in FIG. 5A, the titanium-containing material 520 may be exposed relative to one or more of these materials including multiple different dielectric materials or any number of other semiconductor materials relative to which the titanium-containing material 520 is to be at least partially removed. Together, the exemplar}7substrate may form or be part of a dynamic random access memory7(DRAM) vertical channel transistor (VCT).

[0043] It is to be understood that the noted structure is not intended to be limiting, and any of a variety of other semiconductor structures including titanium-containing materials are similarly encompassed. Other exemplary structures may include two-dimensional and three-dimensional structures common in semiconductor manufacturing, and within which a titanium-containing material, such as titanium nitride, is to be removed relative to one or more other materials, as the present technology may selectively remove titanium-containing materials relative to other exposed materials, such as dielectric materials (e.g., silicon-containing materials) or any of the other materials discussed elsewhere. Additionally, although removal within the feature 512, such as a high-aspect-ratio structure, may benefit from the present technology, the technology may be equally applicable to lower aspect ratios and any other structures. Nevertheless, the substrate 505 may define an exposed region of titanium-containing material 520, such as titanium-and-nitrogen containing material, and an exposed region of one or more silicon-containing materials, such as the first dielectric material 510, the liner material 515, and the second dielectric material 525.

[0044] For example, features 512 according to the present technology may be characterized by any aspect ratios, or the height-to- width ratio of the feature 512. though in some embodiments the features 512 may be characterized by larger aspect ratios, which may not allow sufficient etching utilizing conventional technology7or methodology. For example, in some embodiments the aspect ratio of the features may be greater than or about 2:1, and may be greater than or about 3:1, greater than or about 4:1. greater than or about 5:1, greater than or about 10: 1, greater than or about 20: 1, or greater. Additionally, the feature 512 may be characterized by a reduced width or thickness less than or about 100 nm, less than or about 80 nm, less than or about 60 nm, less than or about 50 nm, less than or about 40 nm, less than or about 30 nm, less than or about 20 nm, less than or about 10 nm, less than or about 5 nm, less than or about 1 nm, or less, including any fraction of any of the stated numbers, such as 20.5 nm, 1.5 nm, etc. This combination of high aspect ratio and minimal width may frustrate many conventional etching operations, or require substantially longer etch times to remove a layer, such as titanium nitride. Moreover, damage to or removal of other exposed layers may occur with conventional technologies as well.

[0045] Method 400 may be performed to remove an exposed titanium-containing material in embodiments, though any number of nitride or titanium-containing materials may be removed in any number of structures in embodiments of the present technology'. The methods may include specific operations for the removal of titanium-containing materials,and may include one or more optional operations to prepare or treat the titanium-containing materials. For example, an exemplary substrate structure may have previous processing residues on a film to be removed, such as titanium nitride. For example, residual photoresist or byproducts from previous processing may reside on the titanium nitride layer. These materials may prevent access to the titanium nitride, or may interact with etchants differently than a clean titanium nitride surface, which may frustrate one or more aspects of the etching. Accordingly, in some embodiments an optional pre-treatment of the titanium-containing material may be performed. Exemplary pre-treatment operations may include a thermal treatment, wet treatment, or plasma treatment, for example, which may be performed in chamber 200 as well as any number of chambers that may be included in system 100 described above.

[0046] In one exemplary plasma treatment, a remote or local plasma may be developed from a precursor intended to interact with residues in one or more ways. For example, utilizing chambers such as chamber 200 described above, either a remote or local plasma may be produced from one or more precursors. For example, an oxygen-containing precursor, a hydrogen-containing precursor, a nitrogen-containing precursor, a helium-containing precursor, or some other precursor may be flowed into a remote plasma region or into the processing region, where a plasma may be struck. The plasma effluents may be flowed to the substrate 405, and may contact the residue material. The plasma process may be either physical or chemical depending on the material to be removed to expose the titanium-containing material. For example, plasma effluents may be flowed to contact and physically remove the residue, such as by a sputtering operation, or the precursors may be flowed to interact with the residues to produce volatile byproducts that may be removed from the chamber.

[0047] Exemplary precursors used in the pre-treatment may be or include hydrogen, a hydrocarbon, water vapor, an alcohol, hydrogen peroxide, or other materials that may include hydrogen as would be understood by the skilled artisan. Exemplary oxygen-containing precursors may include molecular oxygen, ozone, nitrous oxide, nitric oxide, or other oxygen-containing materials. Nitrogen gas may also be used, or a combination precursor having one or more of hydrogen, oxygen, and / or nitrogen may be utilized to remove particular residues. Once the residue or byproducts have been removed, a clean titanium nitride surface may be exposed for etching.

[0048] After any optional pre-treatment. method 400 may include providing an oxy gencontaining precursor to the remote plasma region of the semiconductor processing chamber at operation 405. The oxy gen-containing precursor may be or include atomic oxygen (O), diatomic oxygen (O2), ozone (O3), nitrous oxide (N2O), nitrogen dioxide (NO2), water or steam (H2O), hydrogen peroxide (H2O2), or any other oxy gen-containing precursor used or useful in semiconductor processing. In embodiments, the oxygen-containing precursor may be metal-free. The oxygen-containing precursor may also be provided with any number of carrier gases, which may include nitrogen, helium, argon, or other noble, inert, or useful precursors. The carrier gases may serve to dilute the oxy gen-containing precursor, which may control oxidation, as well as distribute the oxygen-containing precursor.

[0049] A flow rate of the oxy gen-containing precursor may be sufficient to provide adequate oxidation of the one or more dielectric materials, such as the first dielectric material 510, the liner material 515, and the second dielectric material 525. Oxidizing the first dielectric material 510, the liner material 515, and / or the second dielectric material 525 may reduce or prevent etching of the dielectric materials, which again may be silicon-containing materials, to allow for enhanced selectivity of the titanium-containing material removal.

[0050] The flow rate of the oxy gen-containing precursor may be tuned, including in situ, to control the oxidation. For example, the flow rate of the oxygen-containing precursor may be reduced, maintained, or increased during the removal operations. In embodiments, the flow rate of the oxygen-containing precursor may be greater than or about 1 seem, and may be greater than or about 5 seem, greater than or about 10 seem, greater than or about 15 seem, greater than or about 20 seem, greater than or about 25 seem, greater than 50 seem, greater than or about 75 seem, greater or about 100 seem, greater or about 200 seem, or more.Conversely, to limit or control the degree of oxygen-containing precursor present and the resultant oxidation, the flow rate of the oxygen-containing precursor may be less than or about 1,000 seem, and may be less than or about 750 seem, less than or about 500 seem, less than or about 250 seem, less than or about 200 seem, less than or about 150 seem, less than or about 100 seem, less than or about 75 seem, less than or about 50 seem, less than or about 40 seem, less than or about 30 seem, less than or about 20 seem, less than or about 10 seem, or less.

[0051] At operation 410, method 400 may include forming remote plasma effluents of the oxygen-containing precursor in the remote plasma region of the semiconductor processingchamber. Forming plasma effluents of the oxy gen-containing precursor may allow for an increased rate of oxidation of the one or more dielectric materials, such as the first dielectric material 510, the liner material 515, and / or the second dielectric material 525. Additionally, by forming the plasma effluents remotely, the structure 500 may not be directly exposed to plasma formation. Further, ions in the plasma effluents of the oxygen-containing precursor may be filtered in the remote plasma region or when providing the remote plasma effluents of the oxygen-containing precursor to a processing region, as further discussed below.However, while remote plasma formation is discussed, it is also contemplated that the plasma effluents of the oxy gen-containing precursor may be formed locally, such as in the processing region housing the substate 505, instead of remotely.

[0052] A plasma power, or source power, used to form remote plasma effluents of the oxygen-containing precursor may be between about 50 W and about 600 W. At reduced plasma powers, the plasma may not be stable. As such, the plasma power may be greater than or about 50 W, and may be greater than or about 100 W, greater than or about 150 W, greater than or about 200 W, greater than or about 250 W, greater than or about 300 W, greater than or about 350 W. greater than or about 400 W. greater than or about 450 W. greater than or about 500 W, greater than or about 550 W, greater than or about 600 W, or more. Conversely, at increased plasma powers, the resultant plasma effluents may be too aggressive, impacting surface morphology and other materials in the structure 500. As such, the plasma power may be less than or about 600 W, and may be less than or about 550 W, less than or about 500 W. less than or about 450 W, less than or about 400 W. less than or about 350 W, less than or about 300 W, less than or about 250 W, less than or about 200 W, less than or about 150 W, less than or about 100 W, less than or about 50 W, or less.

[0053] Method 400 may include providing the remote plasma effluents of the oxy gencontaining precursor to the processing region of the semiconductor processing chamber at operation 415, which house structure 500. As previously discussed, forming plasma effluents of the oxygen-containing precursor remotely may allow for filtration, or removal, of oxygencontaining ions while providing the remote plasma effluents of the oxygen-containing precursor to the processing region.

[0054] At operation 420, method 400 may include providing a fluorine-containing precursor to the processing region of the semiconductor processing chamber. In embodiments, operations 415 and 420 may be performed simultaneously, such that theremote plasma effluents of the oxy gen-containing precursor and the fluorine-containing precursor are provided to the processing region together. However, it is also contemplated that the remote plasma effluents of the oxy gen-containing precursor and the fluorine-containing precursor may be fluidly isolated and separate until they are in the processing region.

[0055] The fluorine-containing precursor may be provided to the processing region of the semiconductor processing chamber plasma-free. As such, the fluorine-containing precursor may bypass the remote plasma region. The fluorine-containing precursor may be provided in an unexcited state. However, when contacting the remote plasma effluents of the oxy gencontaining precursor, some amount of plasma effluents of the fluorine-containing precursor may form.

[0056] The fluorine-containing precursor may be or include atomic tungsten hexafluoride (WFe), nitrogen trifluoride (NF3), carbon tetrafluoride (CF4), or any other fluorine-containing precursor used or useful in semiconductor processing. Additionally, similar to the oxygencontaining precursor, the fluorine-containing precursor may also be provided with any number of carrier gases, which may include nitrogen, helium, argon, or other noble, inert, or useful precursors. The earner gases may serve to dilute the oxygen-containing precursor, which may control etching, as well as distribute the fluorine-containing precursor.

[0057] The flow rate of the fluorine-containing precursor may be tuned, including in situ, to control the etching. For example, the flow rate of the fluorine-containing precursor may be reduced, maintained, or increased during the removal operations. In embodiments, the flow rate of the fluorine-containing precursor may be greater than or about 1 seem, and may be greater than or about 5 seem, greater than or about 10 seem, greater than or about 15 seem, greater than or about 20 seem, greater than or about 25 seem, greater than 50 seem, greater than or about 75 seem, greater or about 100 seem, greater or about 200 seem, or more.Conversely, to limit or control the degree of oxygen-containing precursor present and the resultant oxidation, the flow rate of the fluorine-containing precursor may be less than or about 1,000 seem, and may be less than or about 750 seem, less than or about 500 seem, less than or about 250 seem, less than or about 200 seem, less than or about 150 seem, less than or about 100 seem, less than or about 75 seem, less than or about 50 seem, less than or about 40 seem, less than or about 30 seem, less than or about 20 seem, less than or about 10 seem, or less.

[0058] A flow rate ratio of the oxy gen-containing precursor provided at operation 405 relative to the fluorine-containing precursor provided at operation 420 may balance and control oxidation and etching. An increased amount to of oxygen-containing precursor relative to the fluorine-containing precursor may result in increased oxidation and reduced etching. As such, an increased amount to of oxygen-containing precursor relative to the fluorine-containing precursor may result in increased selectivity when etching the titani urncontaining material 520 relative to other materials on the substrate 505. In embodiments, the flow rate of the oxy gen-containing precursor may be greater than or about the flow rate of the fluorine-containing precursor. However, if the oxygen-containing precursor is provided in large excess to the fluorine-containing precursor, etching of the titanium-containing material 520 may reduce and even halt. As such, a flow rate ratio of the oxy gen-containing precursor relative to the fluorine-containing precursor may be between about 1:500 and about 500: 1. For example, the flow rate ratio of the oxy gen-containing precursor relative to the fluorine-containing precursor may be greater than or about 1:500, and may be greater than or about 1:250, greater than or about 1 : 100, greater than or about 1 :75. greater than or about 1 :50. greater than or about 1 :25. greater than or about 1:10. greater than or about 1:5, greater than or about 1: 1, greater than or about 5:1, greater than or about 10:1, greater than or about 25 : 1 , greater than or about 50:1, greater than or about 75:1, greater than or about 100:1, greater than about 250: 1, greater than or about 500: 1, or more.

[0059] Method 400 may include contacting the substrate 505 with the remote plasma effluents of the oxygen-containmg precursor and the fluorine-containing precursor.Contacting the substrate 505 with the remote plasma effluents of the oxy gen-containing precursor and the fluorine-containing precursor may also contact the titanium-containing material 520 with the remote plasma effluents of the oxygen-containing precursor and the fluorine-containing precursor. As illustrated in FIG. 5B, the contacting may etch at least a portion of an exposed region of the titanium containing material 520.

[0060] The remote plasma effluents of the oxygen-containing precursor may interact with dielectric materials, other than silicon-and-oxy gen-containing materials, to oxidize the dielectric material. For example, the remote plasma effluents of the oxygen-containing precursor may form Si-0 bonds with any of the dielectric materials, such as the first dielectric material 510, the liner material 515, and the second dielectric material 525. The formation of Si-0 bonds may protect and / or prevent etching of the oxidized dielectric material by the fluorine-containing precursor. Further, the fluorine-containing precursor may interact withthe titanium-containing material 520. The contacting may at least partially form titanium-and-fluorine-containing material from the titanium-containing material 520, which may be titanium-and-nitrogen-containing material, which may volatilize and be removed from the processing region of the semiconductor processing chamber.

[0061] While contacting the substrate 505 with the remote plasma effluents of the oxygencontaining precursor and the fluorine-containing precursor, the processing region may be maintained plasma-free. That is, the processing region may be maintained free of active plasma formation. As such, the only plasma species may be the remotely-formed plasma effluents of the oxygen-containing precursor. However, the remote plasma effluents of the oxygen-containing precursor may interact with the fluorine-containing precursor to at least partially excite the fluorine-containing precursor, which may form plasma effluents of the fluorine-containing precursor.

[0062] By performing operations according to embodiments of the present technology, titanium nitride or other titanium-containing material 520 may be etched selectively relative to other materials, including dielectric materials (e.g., silicon-containing materials), such as the first dielectric material 510, the liner material 515, and the second dielectric material 525. Embodiments of the present technology may etch the titanium-containing material 520 relative to the first dielectric material 510, the liner material 515, and the second dielectric material 525 at a rate of at least about 2:1, and may etch titanium nitride relative to silicon oxide or other materials noted at a selectivity greater than or about 3:1, greater than or about 4:1, greater than or about 5:1, greater than or about 6:1. greater than or about 7:1, greater than or about 8: 1, greater than or about 9:1, greater than or about 10:1, greater than or about 15:1, greater than or about 20: 1, greater than or about 25:1, greater than or about 30:1, greater than or about 35:1, greater than or about 40: 1, greater than or about 45:1, greater than or about 50: 1, or more. For example, etching performed according to some embodiments of the present technology may etch the titanium-containing material 520 while substantially or essentially maintaining the first dielectric material 510, the liner material 515, and the second dielectric material 525.

[0063] Contacting the substrate 505, including the titanium-containing material 520, with the plasma effluents of the oxygen-containing precursor and / or the fluorine-containing precursor may etch the titanium-containing material 520 at an etch rate of greater than or about 15 A / min, and may etch the titanium-containing material 520 at an etch rate of greaterthan or about 15 A / min, greater than or about 20 A / min, greater than or about 22 A / min, greater than or about 24 A / min, greater than or about 25 A / min. greater than or about 26 A / min, greater than or about 28 A / min, greater than or about 30 A / min, or more.

[0064] Processing conditions may impact and facilitate etching according to the present technology. As temperature increases above or about 0 °C, for example, etching begins to increase. As temperature continues to increase, the etch rate may further increase.Accordingly, in some embodiments of the present technology, method 300 may be performed at substrate, pedestal, and / or chamber temperatures of greater than or about 25 °C, and may be performed at temperatures greater than or about 50 °C, greater than or about 75 °C, greater than or about 100 °C, greater than or about 150 °C, greater than or about 200 °C, greater than or about 250 °C, greater than or about 300 °C. greater than or about 350 °C, greater than or about 400 °C, greater than or about 450 °C, greater than or about 500 °C. or more. To control, or reduce, the etch rate, the temperature may be maintained lower. For example, method 300 may be performed at substrate, pedestal, and / or chamber temperatures of less than or about 500 °C, and may be performed at temperatures less than or about 450 °C, less than or about 400 °C, less than or about 350 °C. less than or about 300 °C, less than or about 250 °C, less than or about 200 °C, less than or about 150 °C, less than or about 100 °C, less than or about 75 °C, less than or about 50 °C, less than or about 25 °C, or less. The temperature within the processing region may be maintained at any temperature within these ranges, within smaller ranges encompassed by these ranges, or between any of these ranges.

[0065] The pressure within the chamber may also affect the operations performed.Accordingly, in some embodiments, the pressure within the processing region may be maintained at less than or about 100 Torr, and may be maintained at less than or about 75 Torr, less than or about 50 Torr, less than or about 40 Torr, less than or about 30 Torr, less than or about 20 Torr, less than or about 10 Torr, less than or about 8 Torr, less than or about 6 Torr, less than or about 5 Torr, less than or about 4 Torr, less than or about 3 Torr, less than or about 2 Torr, less than or about 1 Torr, or less, or in the mTorr range (e.g., less than or about 0 Torr). Conversely, at higher temperatures, etch rates may increase. As such, the pressure within the processing region may be maintained at greater than or about 0 Torr, and may be maintained at greater than or about 1 Torr, greater than or about 2 Torr, greater than or about 3 Torr, above or about 4 Ton, greater than or about 5 Torr, greater than or about 6 Torr, greater than or about 7 Torr, greater than or about 8 Torr, greater than or about 9 Torr, greater than or about 10 Torr, greater than or about 15 Torr, greater than or about 20 Torr, greater thanor about 25 Torr, greater than or about 30 Torr, greater than or about 40 Torr, greater than or about 50 Torr, greater than or about 75 Torr, greater than or about 100 Torr, or more. The pressure may also be maintained at any pressure within these ranges, within smaller ranges encompassed by these ranges, or between any of these ranges.

[0066] The previously discussed methods may allow the removal of titanium-containing materials relative to a number of other exposed materials. By utilizing etchants at operating conditions previously described, improved etching of titanium nitride may be performed, which may both increase selectivity over conventional techniques, as well as improve etching access in small pitch features.

[0067] In the preceding description, for the purposes of explanation, numerous details have been set forth in order to provide an understanding of various embodiments of the present technology. It will be apparent to one skilled in the art, however, that certain embodiments may be practiced without some of these details, or with additional details.

[0068] Having disclosed several embodiments, it will be recognized by those of skill in the art that various modifications, alternative constructions, and equivalents may be used without departing from the spirit of the embodiments. Additionally, a number of well-known processes and elements have not been described in order to avoid unnecessarily obscuring the present technology. Accordingly, the above description should not be taken as limiting the scope of the technology. Additionally, methods or processes may be described as sequential or in steps, but it is to be understood that the operations may be performed concurrently, or in different orders than listed.

[0069] Where a range of values is provided, it is understood that each intervening value, to the smallest fraction of the unit of the lower limit, unless the context clearly dictates otherwise, between the upper and low er limits of that range is also specifically disclosed. Any narrow er range betw een any stated values or unstated intervening values in a stated range and any other stated or intervening value in that stated range is encompassed. The upper and lower limits of those smaller ranges may independently be included or excluded in the range, and each range where either, neither, or both limits are included in the smaller ranges is also encompassed within the technology, subject to any specifically excluded limit in the stated range. Where the stated range includes one or both of the limits, ranges excluding either or both of those included limits are also included. "About" and / or “approximately” as used herein when referring to a measurable value such as an amount, atemporal duration, and the like, encompasses variations of ±20% or ±10%, ±5%, or ±0.1% from the specified value, as such variations are appropriate to in the context of the systems, devices, circuits, methods, and other implementations described herein. ‘■Substantially” as used herein when referring to a measurable value such as an amount, a temporal duration, a phy sical attribute (such as frequency), and the like, also encompasses variations of ±20% or ±10%, ±5%, or ±0.1% from the specified value, as such variations are appropriate to in the context of the systems, devices, circuits, methods, and other implementations described herein.

[0070] As used herein and in the appended claims, the singular forms “a”, “an”, and “the” include plural references unless the context clearly dictates otherwise. Thus, for example, reference to “a precursor” includes a plurality of such precursors, and reference to “the material” includes reference to one or more materials and equivalents thereof known to those skilled in the art, and so forth.

[0071] Also, the words “comprise(s)”, “comprising”, “contain(s)”, “containing”, “include(s)”, and “including”, when used in this specification and in the following claims, are intended to specify the presence of stated features, integers, components, or operations, but they do not preclude the presence or addition of one or more other features, integers, components, operations, acts, or groups.

Claims

CLAIMS:

1. A semiconductor processing method comprising:providing an oxygen -containing precursor to a remote plasma region of a semiconductor processing chamber;forming remote plasma effluents of the oxy gen-containing precursor in the remote plasma region of the semiconductor processing chamber;providing the remote plasma effluents of the oxy gen-containing precursor to a processing region of the semiconductor processing chamber, wherein a substrate is housed within the processing region, and wherein the substrate defines an exposed region of a titanium-and-nitrogen containing material and an exposed region of one or more silicon-containing materials;providing a fluorine-containing precursor to the processing region of the semiconductor processing chamber, wherein the fluorine-containing precursor is provided plasma-free; and contacting the substrate with the remote plasma effluents of the oxy gen-containing precursor and the fluorine-containing precursor, wherein the contacting etches at least a portion of the exposed region of a titanium-and-nitrogen-containing material.

2. The semiconductor processing method of claim 1 , wherein the oxygen-containing precursor comprises atomic oxygen (O). diatomic oxygen (O2). ozone (O3), nitrous oxide (N2O), nitrogen dioxide (NO2), water or steam (H2O), or hydrogen peroxide (H2O2).

3. The semiconductor processing method of claim 1 , wherein the remote plasma effluents of the oxy gen-containing precursor are formed at a plasma power of between about 50 W and about 600 W.

4. The semiconductor processing method of claim 1. wherein the one or more silicon-containing materials comprise polysilicon, a silicon-and-oxygen-containing material, or a silicon-and-nitrogen-containing material.

5. The semiconductor processing method of claim 1, wherein the fluorine-containing precursor comprises tungsten hexafluoride (WF<>). nitrogen trifluoride (NFs), or carbon tetrafluoride (CF4).

6. The semiconductor processing method of claim 1, wherein a flow rate of the oxygencontaining precursor is greater than or about a flow rate of the fluorine-containing precursor.

7. The semiconductor processing method of claim 1, wherein the processing region is maintained plasma-free while contacting the substrate with the remote plasma effluents of the oxygen-containing precursor and the fluorine-containing precursor.

8. The semiconductor processing method of claim 1, wherein contacting the substrate with the remote plasma effluents of the oxy gen-containing precursor at least partially oxidizes the exposed region of one or more silicon-containing materials.

9. The semiconductor processing method of claim 1 , wherein the remote plasma effluents of the oxy gen-containing precursor at least partially excite the fluorine-containing precursor.

10. The semiconductor processing method of claim 1, wherein contacting the substrate with the fluorine-containing precursor at least partially converts the exposed region of the titanium-and-nitrogen containing material to a titanium-and-fluorine containing material.

11. A semiconductor processing method comprising:providing an oxygen-containing precursor and a fluorine-containing precursor to a processing region of a semiconductor processing chamber, wherein a substrate is housed within the processing region, and wherein the substrate defines an exposed region of a titanium-and-nitrogen containing material and an exposed region of one or more silicon-containing materials;forming plasma effluents of the oxygen-containing precursor and / or the fluorine-containing precursor; andcontacting the substrate with the plasma effluents of the oxygen-containing precursor and / or the fluorine-containing precursor, w herein the contacting etches at least a portion of the exposed region of a titanium-and-nitrogen containing material.

12. The semiconductor processing method of claim 11 , wherein a flow rate ratio of the fluorine-containing precursor relative to the oxygen-containing precursor is between about 1:500 and about 500:1.

13. The semiconductor processing method of claim 11 , w h erein a temperature within the processing region is maintained at greater than or about 100 °C.

14. The semiconductor processing method of claim 11 , wherein a pressure within the processing region is maintained at less than or about 100 Ton.

15. The semiconductor processing method of claim 11, wherein contacting the substrate with the plasma effluents of the oxygen-containing precursor and / or the fluorine-containing precursor etches the portion of the titanium-and-nitrogen containing material at an etch rate of greater than or about 15 A / min.

16. The semiconductor processing method of claim 11, wherein contacting the substrate with the plasma effluents of the oxygen-containing precursor and / or the fluorine-containing precursor etches the titanium-and-nitrogen containing material relative to the one or more silicon-containing materials at a selectivity' of greater than or about 10: 1.

17. A semiconductor processing method compri sing:providing an oxygen-containing precursor to a remote plasma region of a semiconductor processing chamber;forming remote plasma effluents of the oxy gen-containing precursor in the remote plasma region of the semiconductor processing chamber;providing the remote plasma effluents of the oxy gen-containing precursor to a processing region of the semiconductor processing chamber, wherein a substrate is housed within the processing region, and wherein the substrate defines an exposed region of a titanium-and-nitrogen containing material and an exposed region of one or more silicon-containing materials;providing a fluorine-containing precursor to the processing region of the semiconductor processing chamber, wherein the fluorine-containing precursor is provided plasma-free; and contacting the substrate with the remote plasma effluents of the oxy gen-containing precursor and the fluorine-containing precursor, wherein the contacting etches at least a portion of the exposed region of a titanium-and-nitrogen containing material, wherein a temperature within the processing region is maintained at greater than or about 200 °C and a pressure within the processing region is maintained at greater than or about 1 Torr.

18. The semiconductor processing method of claim 17, wherein:the oxygen-containing precursor comprises diatomic oxygen (O2); andthe fluorine-containing precursor comprises tungsten hexafluoride (WFe).

19. The semiconductor processing method of claim 17, further comprising: providing one or more inert gases with the oxygen-containing precursor and / or the fluorine-containing precursor.

20. The semiconductor processing method of claim 17, wherein contacting the substrate wi th the remote plasma effluents of the oxy gen-containing precursor and the fluorine-containing precursor etches the portion of the titanium-and-nitrogen containing material at an etch rate of greater than or about 25 A / min.

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