Field-suppressed metal gap fill

Abstract

The embodiments of the present disclosure relate to methods for bottom-up metal gap filling without substantial deposition outside the feature. Additional embodiments provide a method for forming a metal material on the top surface of a substrate and on the bottom surface of a feature before depositing the metal gap fill.

Description

Technology Field

[0001] The embodiments of the present disclosure relate to methods for depositing metal films within substrate features. More specifically, the embodiments of the present disclosure relate to methods for minimizing deposition outside substrate features while providing a bottom-up gapfill. Background Technology

[0002] The gap-fill process is essential for various semiconductor manufacturing processes. The gap-fill process can be used to fill gaps (or features) with insulating or conductive materials. For example, shallow trench isolation, intermetallic dielectric layers, passivation layers, and dummy gates are all typically implemented by gap-fill processes.

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

[0004] The most common deposition methods, particularly chemical vapor deposition methods, deposit more material on the substrate surface than within the feature, especially near the bottom of the feature.

[0005] Consequently, the film on the substrate surface must be removed via an etching process after the gap-fill deposition is completed. This additional processing step reduces throughput, which increases manufacturing costs.

[0006] Other gap-fill methods rely on atomic layer deposition to form metallic gap-fill materials. These methods typically create shape-following films on all substrate surfaces. Accordingly, these methods also require etching of the material deposited outside the feature, but they also often create gap-fills with seams in the middle as the films are formed from sidewalls and meet in the middle.

[0007] Accordingly, there is a need for gap-fill methods that allow for greater throughput by minimizing field deposition, and also for processes that deposit in a bottom-up manner to avoid defects in the gap-fill.

[0008] One or more embodiments of the present disclosure relate to a method for depositing a metal gap fill. The method comprises the step of exposing a substrate surface to a first metal halide and a reducing agent to form a first metal gap fill within at least one feature — at least one feature is formed on the substrate surface —. The at least one feature has an opening, two sidewalls, and extends to a depth from the top surface to the bottom. The thickness of the first metal on the bottom is greater than the thickness of the first metal on the top surface.

[0009] Additional embodiments of the present disclosure relate to a method for depositing a first metal gap fill. The method comprises the steps of depositing a second metal material comprising tungsten on a substrate surface by physical vapor deposition—where at least one feature is formed on the substrate surface—and exposing the substrate surface to a reducing agent comprising a first metal halide comprising MoCl5 and H2 to form a first metal gap fill in a bottom-up, non-shape-following manner within the at least one feature. The at least one feature has an opening, two sidewalls, and extends in depth from the top surface to the bottom. The second metal material is deposited on the top surface and the bottom. The molar ratio of the reducing agent to the first metal halide is about 3000 or less, and the at least one feature is filled without substantial deposition on the top surface. Brief explanation of the drawing

[0010] To ensure that the features of the above-mentioned disclosure are understood in detail, a more specific description of the disclosure briefly summarized above may be made with reference to embodiments, some of which are illustrated in the accompanying drawings. However, it should be noted that the accompanying drawings are merely illustrative of typical embodiments of the disclosure and should not be construed as limiting the scope of the disclosure, as the disclosure may allow for other equally valid embodiments. In the illustrations of the accompanying drawings where similar reference numerals indicate similar elements, embodiments as described herein are illustrated as examples, not as limitations. FIG. 1 illustrates a process flow diagram of a deposition method according to one or more embodiments. FIGS. 2a to 2c illustrate cross-sectional views of a substrate during processing according to one or more embodiments. FIG. 3 illustrates a schematic plan view of a multi-chamber processing system according to one or more embodiments. Specific details for implementing the invention

[0011] Before describing some exemplary embodiments of the present disclosure, it should be understood that the present disclosure is not limited to the details of the configurations or process steps described in the following description. Other embodiments of the present disclosure are possible and may be implemented or carried out in various ways.

[0012] The term "approximately" as used herein means approximately or nearly, and in the context of a stated numerical value or range, means a variation of ±15% or less of the numerical value. For example, values ​​differing by ±14%, ±10%, ±5%, ±2%, ±1%, ±0.5%, or ±0.1% will satisfy the definition of approximately.

[0013] As used in this specification and the appended claims, the terms “substrate” or “wafer” refer to a surface or a portion of a surface on which a process is performed. It will also be understood by those skilled in the art that references to a substrate may refer to only a portion of the substrate unless the context clearly indicates otherwise. Additionally, references to deposition on a substrate may mean both a substrate on which one or more films or features are deposited or formed and a bare substrate.

[0014] As used herein, the term “substrate” refers to any substrate or a material surface formed on a substrate upon which film treatment is performed during a manufacturing process. For example, substrate surfaces upon which treatment may be performed include, depending on the application, materials such as silicon, silicon oxide, strained silicon, silicon on insulator (SOI), carbon-doped silicon oxides, amorphous silicon, doped silicon, germanium, gallium arsenide, and any other materials, such as metals, metal nitrides, metal alloys, and other conductive materials. Substrates include, without limitation, semiconductor wafers. Substrates may be exposed to a pretreatment process to polish, etch, reduce, oxidize, hydroxylate, anneale, and / or bake the substrate surface. In the present disclosure, in addition to performing film treatment directly on the surface of the substrate itself, any of the disclosed film treatment steps may also be performed on an underlying layer formed on the substrate, as disclosed in more detail below, and the term “substrate surface” is intended to include such underlying layer as indicated by the context. Accordingly, for example, where a film / layer or partial film / layer is deposited on the substrate surface, the exposed surface of the newly deposited film / layer becomes the substrate surface.

[0015] As used herein, the term “substrate surface” refers to any substrate surface on which a layer may be formed. The substrate surface may have one or more features formed on the substrate surface, one or more layers formed on the substrate surface, and combinations thereof. The shape of the features may 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 intentional surface irregularity. Suitable examples of features include, but are not limited to, trenches extending into the substrate and having a top, two sidewalls, and a bottom, and vias having one or more sidewalls extending into the substrate to the bottom.

[0016] As used in this specification and the appended claims, the term “selectively” refers to a process that acts with greater effect on a first surface than on a second surface. Such a process will be described as acting “selectively” on the first surface relative to the second surface. In this regard, the term “over” does not mean the physical orientation of one surface on the top of another surface, but rather the relationship of the thermodynamic or kinetic properties of the chemical reaction between one surface and the other surface.

[0017] The terms "on" or "on" indicate that direct contact exists between elements. The term "directly on" indicates that direct contact exists between elements without any intervening elements.

[0018] As used in this specification and the appended claims, terms such as "precursor," "reactant," and "reactive gas" are used interchangeably to refer to any gaseous species capable of reacting with the substrate surface.

[0019] Embodiments of the present disclosure advantageously provide methods for depositing a metallic gap fill in which deposition outside of substrate features is reduced or eliminated. Additional embodiments advantageously provide methods for depositing a gap fill in which the need for subsequent etching to remove deposition outside of filled features is reduced. Additional embodiments provide methods for forming a metallic gap fill in a bottom-up manner.

[0020] Embodiments of the present disclosure are described by drawings illustrating processes and substrates according to one or more embodiments of the present disclosure. The illustrated processes, diagrams, and resulting substrates are merely illustrative of the disclosed processes, and a person skilled in the art will recognize that the disclosed processes are not limited to the illustrative applications.

[0021] Referring to FIGS. 1 to 2c, the present disclosure relates to a method (100) for depositing a metal gap fill. FIG. 1 depicts a process flowchart of a deposition method (100) according to one or more embodiments of the present disclosure. FIGS. 2a to 2c depict a substrate during processing according to one or more embodiments of the present disclosure.

[0022] FIG. 2a illustrates a substrate (200) having a substrate surface (205). As identified above, the substrate surface refers to an exposed surface of the substrate on which a layer may be formed. The substrate surface (205) has at least one feature (210) formed on the substrate surface. Although only a single feature is shown in the drawings, a person skilled in the art will recognize that multiple features will be affected in a similar manner by the disclosed methods.

[0023] At least one feature (210) has an opening (212) having a width (W). The opening (212) is formed on the uppermost surface (215) of the substrate (200). The feature (210) also has one or more side walls (214), and a depth (D) extends from the uppermost surface (215) to the lowermost (216). Although straight vertical side walls are shown in the drawings, the disclosed methods can also be performed on inclined, irregular, or reentrant side walls.

[0024] In some embodiments, the width (W) of the opening (212) is about 10 nm or more, about 15 nm or more, about 20 nm or more, about 25 nm or more, about 30 nm or more, or about 35 nm or more. In some embodiments, the width (W) is in the range of about 10 nm to about 35 nm. Those skilled in the art will recognize that the difficulty of depositing metal gap fills on features that are narrowing (also known as critical dimension (CD)) is increasing. In some embodiments, at least one feature has an aspect ratio (D / W) in the range of about 1 to about 10 or in the range of about 1 to about 6.

[0025] Referring to FIG. 1 and FIG. 2b, in some embodiments, the method (100) begins with an optional operation (110). In 110, a second metal material (220) is deposited on a substrate surface (205). As illustrated, the second metal material (220) is deposited prior to the first metal gap fill (230) discussed below. To avoid confusion, the alias "second" is used only as a distinguishing identifier and should not be interpreted as implying any order of operations of the methods disclosed herein. In some embodiments, as illustrated in FIG. 2b, the second metal material is deposited on the top surface (215) and the bottom surface (216). In some embodiments, the second metal material is not deposited on the sidewall (214).

[0026] In some embodiments, the second metal material (220) has a top thickness (T) on the top surface (215). T ) and the lowest thickness (T) on the lowest part (216) B It has ). In some embodiments, the top thickness (T T ) is the lowest thickness (T B It is greater than ). In some embodiments, the top thickness (T T ) is at least 50 Å. In some embodiments, the bottom thickness (T B ) is at least 25 Å. In some embodiments, the top thickness (T T ) is approximately 60 Å, and the bottom thickness (T B ) is within the range of about 30 Å to about 40 Å.

[0027] In some embodiments, the operation (110) is performed by physical vapor deposition (PVD). In some embodiments, the temperature of the PVD process is in the range of about 350 °C to about 450 °C or about 400 °C. In some embodiments, the pressure of the PVD process is in the range of about 200 mTorr to about 500 mTorr, in the range of about 300 mTorr to about 400 mTorr or about 325 mTorr. In some embodiments, the RF power of the PVD process is in the range of about 3000 W to about 5000 W or about 4000 W. In some embodiments, the bias of the PVD process is in the range of about 20 W to about 100 W or about 50 watts.

[0028] In some embodiments, the second metal material (220) deposited by the operation (110) is essentially composed of tungsten (W). As used in this context, a material "essentially composed of," that is, essentially composed of the mentioned element, contains more than about 98%, more than about 99%, or more than about 99.5% of the mentioned element on an atomic basis.

[0029] In some embodiments, the top surface (215) and the bottom surface (216) comprise a metallic material, while the sidewall (214) comprises a dielectric. Although such an arrangement of material surfaces is conceived to exist after operation (110), it is equally conceived by the inventors that such an arrangement of material surfaces can be achieved by other means known to those skilled in the art. In some embodiments, the metallic material on the top surface (215) and / or the bottom (216) comprises one or more of ruthenium (Ru), molybdenum (Mo), or tungsten (W).

[0030] The method (100) continues in operation (120), wherein a substrate surface is exposed to a first metal halide and a reducing agent to form a first metal gap fill (230) within at least one feature (210). In some embodiments, the thickness of the first metal gap fill (230) on the bottom (216) is greater than the thickness of the first metal gap fill (230) on the top surface (215).

[0031] Without being bound by theory, one possible explanation is that the metal halide acts to perform both deposition and etching of the deposited film. Consequently, since the top surface is exposed to the metal halide more, the deposited metal on the top surface is etched more easily than the deposited metal on the bottom of the feature, which is better protected. Another possible explanation is that deposition on the top surface is inhibited by the top surface becoming saturated with halide reaction byproducts.

[0032] In some embodiments, in operation (120), the substrate surface (205) is simultaneously exposed to the first metal halide and the reducing agent. In other words, in some embodiments, the reaction between the first metal halide and the reducing agent occurs primarily within the gaseous phase on the substrate. Those skilled in the art will recognize this as a chemical vapor deposition (CVD) process. In some embodiments, both the first metal halide and the reducing agent flow continuously into the processing space on the substrate. In some embodiments, the metal halide flows continuously, while the reducing agent flows pulsed or intermittently.

[0033] The first metal halide may be any suitable compound containing halide ligands that reacts with a reducing agent to form a metal film. In some embodiments, the first metal halide comprises one or more of molybdenum (Mo), cobalt (Co), or tungsten (W). In some embodiments, the first metal halide comprises one or more of MoCl5, MoOCl4, MoO2Cl2, or MoF6. In some embodiments, the first metal halide is essentially composed of MoCl5. In some embodiments, the first metal halide comprises one or more of CoCl2, CoF2, or CoF3. In some embodiments, the first metal halide comprises one or more of WF6 and WCl6.

[0034] In some embodiments, the first metal halide is delivered from a heated ampoule together with a carrier gas. The carrier gas may be any suitable inert gas that does not react with the first metal halide or otherwise alter it. In some embodiments, the carrier gas comprises argon.

[0035] The reducing agent may be any suitable compound for reducing the first metal halide to form the first metal gap fill. In some embodiments, the reducing agent comprises H2 or is essentially composed of H2. As used in this context, a reactant "essentially composed of," that is, essentially composed of the mentioned compound, comprises at least about 98%, at least about 99%, or at least about 99.5% of the mentioned compound on a molar basis. It is noted that inert carriers and / or diluent gases are not included.

[0036] The inventors have surprisingly discovered that using a relatively large amount of the first metal halide relative to the reducing agent still provides suitable growth on the bottom surface while providing little to no growth on the top surface. In some embodiments, the molar ratio of the reducing agent to the first metal halide is about 3000 or less. In some embodiments, the molar ratio is 2800 or less, 2500 or less, or 2000 or less. As used herein, the molar ratio is the molar ratio of the total gas flows over a certain period of time. For example, when the metal halide is continuously flowing while the reducing agent is pulsed, the molar ratio is based on both the total flow of the reducing agent and the total flow of the metal halide (even when the reducing agent is not flowing).

[0037] In some embodiments, the processing conditions of the method (100) may be controlled. In some embodiments, the substrate (200) is maintained at a predetermined temperature during the operation (120). In some embodiments, the substrate (200) is maintained at a temperature within the range of about 350°C to about 450°C. In some embodiments, the substrate (200) is maintained at a temperature of 425°C.

[0038] In some embodiments, the first metal gap fill (230) is deposited in a non-shape-following manner. "Non-shape-following manner" means that the deposited material has a variable thickness over the substrate surface (205). For example, in some embodiments, the thickness of the first metal gap fill on the bottom (216) may be thicker than the thickness of the first metal gap fill (230) on the sidewall (214) or the top surface (215).

[0039] In some embodiments, the first metal gap fill (230) is deposited in a bottom-up manner. The 'bottom-up manner' means that the method does not deposit the first metal gap fill (230) on the sidewall (214) with little to no deposit, but rather, the deposition of the first metal gap fill (230) occurs mainly on the bottom (216). Accordingly, the first metal gap fill (230) grows upward from the bottom (216) of at least one feature (210).

[0040] In some embodiments, as illustrated in FIG. 2c, the first metal gap fill (230) fills the entire depth (D) of at least one feature (210). In some embodiments, at least one feature (210) is filled without substantial deposition on the top surface (215). As used in this context, "substantial deposition" refers to the deposition of a continuous film having a thickness of about 5%, about 2%, or about 1% of the depth of at least one feature (210). In other words, the gap fill process is optional, with a thickness of about 20 times, about 50 times, or about 100 times greater than the bottom surface relative to the top surface.

[0041] To achieve the desired molar ratio and the resulting gap-filling effect, the inventors have discovered that increasing the ampoule temperature can help provide additional metal halides into the reaction space and achieve the desired molar ratio. In some embodiments, the ampoule temperature is set within the range of about 90 °C to about 120 °C. Additionally, the inventors have discovered that a lower processing pressure helps to volatilize additional amounts of the first metal halide and helps achieve the desired molar ratio. In some embodiments, the operation (120) is performed at a pressure within the range of about 20 Torr to about 50 Torr, or about 30 Torr to about 60 Torr.

[0042] FIG. 3 is a schematic plan view of an exemplary multi-chamber processing system (300) according to embodiments of the present disclosure. The processing system (300) generally comprises a factory interface (302), load lock chambers (304, 306), transfer chambers (308, 310) having individual transfer robots (312, 314), holding chambers (316, 318), and processing chambers (320, 322, 324, 326, 328, 330). As described in detail herein, wafers within the processing system (300) can be processed in various chambers and transferred between the chambers without exposing the wafers to an ambient environment outside the processing system (300) (e.g., an atmospheric environment that may exist in a fab). For example, wafers may be processed in various chambers of a low pressure (e.g., about 300 Torr or less) or vacuum environment between various processes performed on wafers within the processing system (300), and may be transferred between the various chambers without breaking the low pressure or vacuum environment. Accordingly, the processing system (300) can provide an integrated solution for some processing of wafers.

[0043] Examples of processing systems that may be suitably modified in accordance with the teachings provided herein include Endura®, Producer®, or Centura® integrated processing systems or other suitable processing systems that are commercially available from Applied Materials, Inc., located in Santa Clara, California. Other processing systems (including processing systems from other manufacturers) are considered to be adaptable to benefit from the aspects described herein.

[0044] In the example illustrated in FIG. 3, the factory interface (302) includes a docking station (340) and factory interface robots (342) to facilitate the transfer of wafers. The docking station (340) is configured to accommodate one or more front opening unified pods (FOUPs) (344). In some examples, each factory interface robot (342) generally includes a blade (348) positioned on one end of the individual factory interface robot (342) configured to transfer wafers from the factory interface (302) to load lock chambers (304, 306).

[0045] The load lock chambers (304, 306) have individual ports (350, 352) coupled to the factory interface (302) and individual ports (354, 356) coupled to the transfer chamber (308). The transfer chamber (308) additionally has individual ports (358, 360) coupled to the holding chambers (316, 318) and individual ports (362, 364) coupled to the processing chambers (320, 322). Similarly, the transfer chamber (310) has individual ports (366, 368) coupled to the holding chambers (316, 318) and individual ports (370, 372, 374, 376) coupled to the processing chambers (324, 326, 328, 330). The ports (354, 356, 358, 360, 362, 364, 366, 368, 370, 372, 374, 376) may be slit valve openings having slit valves to allow wafers to pass through them by, for example, transfer robots (312, 314) and to provide a seal between individual chambers to prevent gas from passing between individual chambers. Generally, any port is opened to transfer wafers through the port. Otherwise, the port is closed.

[0046] Load lock chambers (304, 306), transfer chambers (308, 310), holding chambers (316, 318), and processing chambers (320, 322, 324, 326, 328, 330) may be fluidly coupled to a gas and pressure control system (not specifically illustrated). The gas and pressure control system may include one or more gas pumps (e.g., turbopumps, cryo-pumps, roughing pumps), gas sources, various valves, and conduits fluidly coupled to the various chambers. In operation, a factory interface robot (342) transfers a wafer from the FOUP (344) to the load lock chamber (304 or 306) through a port (350 or 352). Next, the gas and pressure control system pumps down the load lock chamber (304 or 306). The gas and pressure control system additionally maintains the transfer chambers (308, 310) and holding chambers (316, 318) in a low-pressure or vacuum environment (which may contain an inert gas). Thus, pumping down the load lock chamber (304 or 306) facilitates, for example, transferring a wafer between the atmospheric environment of the factory interface (302) and the low-pressure or vacuum environment of the transfer chamber (308).

[0047] With the wafer in the pumped-down load lock chamber (304 or 306), the transfer robot (312) transfers the wafer from the load lock chamber (304 or 306) into the transfer chamber (308) through the port (354 or 356). Subsequently, the transfer robot (312) can transfer the wafer to any of the processing chambers (320, 322) for processing through individual ports (362, 364) and to holding chambers (316, 318) for holding to wait for further transfer, and / or transfer between any of the processing chambers and the holding chambers. Similarly, the transfer robot (314) can access the wafer in the holding chamber (316 or 318) through the port (366 or 368), and can transfer the wafer to any of the processing chambers (324, 326, 328, 330) for processing through the individual ports (370, 372, 374, 376) and to the holding chambers (316, 318) for holding to await further transfer, and / or transfer it between any of the processing chambers and the holding chambers. Transfer and holding of the wafer within and between the various chambers can be performed in a low-pressure or vacuum environment provided by a gas and pressure control system.

[0048] The processing chambers (320, 322, 324, 326, 328, 330) may be any suitable chamber for processing wafers. In some embodiments, the processing chamber (320) may be capable of performing an annealing process, the processing chamber (322) may be capable of performing a cleaning process, and the processing chambers (324, 326, 328, 330) may be capable of performing epitaxial growth processes. In some embodiments, the processing chamber (322) may be capable of performing a cleaning process, the processing chamber (320) may be capable of performing an etching process, and the processing chambers (324, 326, 328, 330) may be capable of performing individual epitaxial growth processes. The processing chamber (322) may be a SiCoNi™ Preclean chamber available from Applied Materials in Santa Clara, California. The processing chamber (320) may be a Selectra™ Etch chamber available from Applied Materials in Santa Clara, California.

[0049] A system controller (390) is coupled to the processing system (300) to control the processing system (300) or its components. For example, the system controller (390) can control the operation of the processing system (300) by using direct control of the chambers (304, 306, 308, 316, 318, 310, 320, 322, 324, 326, 328, 330) of the processing system (300) or by controlling controllers associated with the chambers (304, 306, 308, 316, 318, 310, 320, 322, 324, 326, 328, 330). During operation, the system controller (390) enables data collection and feedback from individual chambers to adjust the performance of the processing system (300).

[0050] The system controller (390) generally includes a central processing unit (CPU) (392), memory (394), and support circuits (396). The CPU (392) may be any type of general-purpose processor that can be used in an industrial setting. The memory (394) or non-transient computer-readable medium is accessible by the CPU (392) and may be one or more of memory, such as random access memory (RAM), read-only memory (ROM), floppy disk, hard disk, or any other type of local or remote digital storage. The support circuits (396) are coupled to the CPU (392) and may include caches, clock circuits, input / output subsystems, power supplies, etc. The various methods disclosed herein may generally be implemented under the control of the CPU (392) by the CPU (392) executing computer instruction code stored in memory (394) (or memory of a specific process chamber) as a software routine, for example. When a computer instruction code is executed by the CPU (392), the CPU (392) controls the chambers to perform processes according to various methods.

[0051] Other processing systems may have different configurations. For example, more or fewer processing chambers may be combined with a transfer device. In the illustrated example, the transfer device includes transfer chambers (308, 310) and holding chambers (316, 318). In other examples, more or fewer transfer chambers (e.g., one transfer chamber) and / or more or fewer holding chambers (e.g., no holding chambers) may be implemented as the transfer device of the processing system.

[0052] The processes may generally be stored in the memory of a system controller (390) as software routines that cause the process chamber to perform the processes of the present disclosure when executed by a processor. The software routines may also be stored and / or executed by a second processor (not shown) located remotely from the hardware controlled by the processor. Some or all of the methods of the present disclosure may also be performed in hardware. Therefore, the processes may be implemented in software and executed in hardware using a computer system, such as as a custom integrated circuit or other type of hardware implementation, or as a combination of software and hardware. When executed by a processor, the software routines convert a general-purpose computer into a specific-purpose computer (controller) that controls the chamber operation to perform the processes.

[0053] Embodiments of the present disclosure relate to a non-transient computer-readable medium. In one or more embodiments, the non-transient computer-readable medium comprises instructions, which, when executed by a controller of a processing chamber, cause the processing chamber to perform operations of any of the methods described herein (e.g., deposition method (100)). In one or more embodiments, the controller causes the processing chamber to perform operations of the deposition method (100). In one or more embodiments, the controller causes the processing chamber to perform operations (operations (110)) of depositing a second metal material on a substrate surface having at least one feature. The at least one feature includes at least one surface defining a via having a bottom surface and at least one sidewall. In one or more embodiments, the controller causes the processing chamber to perform operations (operations (120)) of exposing to a first metal halide and a reducing agent to form a first metal gap fill within the at least one feature.

[0054] Spatially relative terms such as “below,” “bottom,” “lower,” “top,” and “upper” may be used herein for ease of description to explain the relationship of one element or feature to another element(s) or feature(s) as illustrated in the drawings. It will be understood that spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientations illustrated in the drawings. For example, if the device in the drawings is inverted, elements described as “below” or “bottom” of other elements or features will be oriented “top” of other elements or features. Accordingly, the exemplary term “below” may encompass both top and bottom orientations. The device may be oriented in other ways (rotated 90 degrees or other orientations), and the spatially relative terms used herein are interpreted accordingly.

[0055] In the context of describing the materials and methods discussed herein (particularly in the context of the following claims), the use of singular terms and similar referents is to be interpreted as encompassing both singular and plural forms, unless otherwise indicated herein or clearly negated by the context. Unless otherwise indicated herein, references to ranges of values ​​herein are intended merely to serve as a method of abbreviating each distinct value within that range, and each distinct value is included in the specification as they are individually referred to herein. Unless otherwise indicated herein or clearly negated by the context, all methods described herein may be performed in any suitable order. Any and all examples provided herein, or the use of exemplary vocabulary (e.g., “for instance” and “same as”), are intended merely to clarify the materials and methods and, unless otherwise stated, do not limit the scope. No vocabulary in the specification shall be interpreted as indicating any unstated element as essential to carrying out the disclosed materials and methods.

[0056] Throughout this specification, references to “one embodiment,” “specific embodiments,” “one or more embodiments,” or “exemplars” mean that a specific feature, structure, material, or property described in relation to an embodiment is included in at least one embodiment of this disclosure. Accordingly, the appearance of phrases such as “in one or more embodiments,” “in specific embodiments,” “in one embodiment,” or “in an embodiment” at various locations throughout this specification does not necessarily refer to the same embodiment of this disclosure. In one or more embodiments, specific features, structures, materials, or properties are combined in any suitable manner.

[0057] Although the disclosure herein has been described with reference to specific embodiments, it should be understood that such 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. Accordingly, the disclosure is intended to include modifications and variations within the scope of the appended claims and their equivalents.

Claims

Claim 1 As a method, the step of exposing a substrate surface on which at least one feature is formed to a first metal halide and a reducing agent to form a first metal gap fill within at least one feature — said at least one feature has an opening, two sidewalls, and extends in depth from a top surface to a bottom surface, said top surface and said bottom surface comprise a metallic material and said sidewalls comprise a dielectric material —; A method comprising the step of depositing a second metal material comprising tungsten (W) on the substrate surface before forming the first metal gap fill—the second metal material being directly deposited by physical vapor deposition (PVD) on the top surface and the bottom surface and not on the sidewalls, the first metal gap fill being deposited in a bottom-up, non-shape-following manner, and at least one feature being filled without substantial deposition of the first metal gap fill on the top surface, and the thickness of the first metal gap fill on the bottom surface being greater than the thickness of the first metal gap fill on the top surface. Claim 2 A method according to claim 1, wherein the first metal halide and the reducing agent are simultaneously exposed to the surface of the substrate. Claim 3 A method according to paragraph 2, wherein the reducing agent is pulsed or intermittently flowed while the metal halide is continuously flowed. Claim 4 A method according to claim 1, wherein the first metal halide comprises one or more of molybdenum, cobalt, or tungsten. Claim 5 A method according to claim 1, wherein the first metal halide is essentially composed of MoCl5. Claim 6 In claim 1, the reducing agent comprises H2. Claim 7 A method according to claim 1, wherein the molar ratio of the reducing agent to the first metal halide is 3000 or less. Claim 8 A method according to claim 1, wherein the opening has a width within the range of 10 nm to 35 nm. Claim 9 A method according to claim 1, wherein the ratio between the depth and width of the opening is within the range of 1 to 10. Claim 10 delete Claim 11 A method according to claim 1, wherein the metallic material comprises one or more of Ru, Mo, or W. Claim 12 delete Claim 13 A method according to claim 1, wherein the substrate is maintained at a temperature within the range of 350 ℃ to 450 ℃. Claim 14 delete Claim 15 delete Claim 16 delete Claim 17 A method according to claim 1, wherein the second metal material has a thickness of at least 25 Å on the lowest surface and a thickness of at least 50 Å on the uppermost surface. Claim 18 delete Claim 19 delete Claim 20 As a method, a second metallic material comprising tungsten (W) is deposited on a substrate surface by physical vapor deposition (PVD) ― said substrate surface has at least one feature formed, said at least one feature has an opening and two sidewalls and extends in depth from a top surface to a bottom surface, said top surface and said bottom surface comprise a metallic material and said sidewalls comprise a dielectric material, and said second metallic material is deposited on said top surface and said bottom surface and not on said sidewalls ―; A method comprising the step of exposing the substrate surface to a reducing agent comprising a first metal halide comprising MoCl5 and H2 in order to form a first metal gap fill on the second metal material on the bottom surface in a bottom-up non-shape-following manner within the at least one feature — wherein the molar ratio of the reducing agent to the first metal halide is 3000 or less, and the at least one feature is filled without substantial deposition of the first metal gap fill on the top surface.

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