Methods of forming polycrystalline molybdenum films and related structures including polycrystalline molybdenum films

Abstract

Methods for forming a polycrystalline molybdenum film on a substrate surface are disclosed. The method may include providing a substrate into a reaction chamber; depositing a nucleation membrane directly on the exposed surface of the substrate, wherein the nucleation membrane comprises one of a metal oxide nucleation membrane or a metal nitride nucleation membrane; and depositing the polycrystalline molybdenum film directly on the nucleating film; wherein the polycrystalline molybdenum film comprises a plurality of molybdenum crystallites having an average crystallite size of less than 80. Structures including a polycrystalline molybdenum film disposed on a surface of a substrate having an intermediate nucleation film are also disclosed.

Description

[0001] This application is a divisional application of the patent application filed on August 17, 2020, with application number 202010823880.8 and entitled "Method for forming a polycrystalline molybdenum film and related structures including a polycrystalline molybdenum film".

[0002] Cross-reference to related applications

[0003] This application relates to a co-application entitled “Method for depositing a molybdenum nitride film on a substrate surface by a cyclic deposition process and an associated semiconductor device structure including a molybdenum nitride film” (application serial number 62 / 891,254), which was filed on the same date as this application and whose entire contents are incorporated herein by reference. Technical Field

[0004] This disclosure generally relates to methods for forming polycrystalline molybdenum films on a substrate surface, and more particularly to methods for directly depositing a nucleation film on the substrate surface and then directly depositing a polycrystalline molybdenum film on the nucleation film. This disclosure also generally relates to structures including a polycrystalline molybdenum film directly disposed on the nucleation film. Background Technology

[0005] Semiconductor device manufacturing processes in advanced technology nodes typically require existing deposition processes to form metal films, such as polycrystalline molybdenum films.

[0006] A common requirement for depositing metal films is that the deposition process is highly conformal. For example, conformal deposition is often required to uniformly deposit metal films over three-dimensional structures that include high aspect ratio nonplanar features. Another common requirement for depositing metal films is that the deposition process can deposit continuous ultrathin films over large substrate areas. In the specific case where the metal film is conductive, it may be necessary to optimize the deposition process to produce low resistivity films. For example, low resistivity metal films commonly used in prior art semiconductor device applications can include tungsten and / or copper. However, tungsten and copper films typically require a thick barrier layer between the metal film and the dielectric material. The thick barrier layer can be used to prevent the metal material from diffusing into the underlying dielectric material, thereby improving device reliability and device yield. However, thick barrier layers typically exhibit high resistivity, thus leading to an increase in the overall resistivity of the semiconductor device structure.

[0007] Potential replacements for tungsten and copper films in next-generation devices could include molybdenum films. For example, molybdenum (Mo), a low-resistivity refractory metal, could potentially replace tungsten as a material in memory, logic circuits, and other devices using polycrystalline silicon-metal gate electrode structures. Molybdenum films can also be used in some organic light-emitting diodes, liquid crystal displays, and thin-film solar cells and photovoltaic cells.

[0008] Additionally, in certain semiconductor manufacturing processes, it may be necessary to form metal films, such as polycrystalline molybdenum films, within non-planar features (e.g., vertical and / or horizontal trenches) disposed in / on a substrate. Forming metal films within non-planar features can at least partially or completely fill the non-planar features with the metal film; this method is commonly referred to as "gap filling." As the geometry of semiconductor device structures has decreased, and high aspect ratio non-planar features have become increasingly prevalent in device structures such as DRAM, 3D-NAND, flash memory, and logic circuits, filling non-planar features with metal films possessing the desired properties has become increasingly difficult.

[0009] Therefore, there is a need for methods and related structures for forming polycrystalline molybdenum films with low resistivity and physical properties that enable polycrystalline molybdenum interstitial filling processes on substrates including nonplanar features. Summary of the Invention

[0010] This overview is provided to introduce a set of concepts in a simplified form. These concepts are described in more detail below in the detailed description of exemplary embodiments of this disclosure. This overview is not intended to identify key or essential features of the claimed subject matter, nor is it intended to limit the scope of the claimed subject matter.

[0011] In some embodiments, a method for forming a polycrystalline molybdenum film above a substrate surface is provided. The method may include: providing a substrate into a reaction chamber; depositing a nucleation film directly onto an exposed surface of the substrate, wherein the nucleation film comprises one of a metal oxide nucleation film or a metal nitride nucleation film; and depositing a polycrystalline molybdenum film directly onto the nucleation film, wherein the polycrystalline molybdenum film comprises a plurality of molybdenum crystallites having an average crystallite size of less than 80 Å.

[0012] In some embodiments, a structure including a polycrystalline molybdenum film is provided. The structure may include: a substrate surface; a nucleation film directly disposed on the substrate surface, wherein the nucleation film comprises at least one of a metal oxide nucleation film or a metal nitride nucleation film; and a polycrystalline molybdenum film directly disposed on the nucleation film; wherein the polycrystalline molybdenum film comprises a plurality of molybdenum crystallites having an average crystallite size of less than 80 Å.

[0013] For the purpose of summarizing the invention and its advantages over the prior art, certain objectives and advantages of the invention have been described in the foregoing. It should be understood, of course, that not all such objectives or advantages may be achieved according to any particular embodiment of the invention. Therefore, by way of example, those skilled in the art will recognize that the invention may be embodied or practiced in a manner that achieves or optimizes one or more advantages taught or stated herein, without necessarily achieving other objectives or advantages that may be taught or stated herein.

[0014] All these embodiments are intended to be within the scope of the disclosed invention. These and other embodiments will be apparent to those skilled in the art from the following detailed description of certain embodiments taken in conjunction with the accompanying drawings, and the invention is not limited to any particular embodiment disclosed. Attached Figure Description

[0015] Although this specification concludes with claims that specifically point out and expressly claim protection to the contents regarded as embodiments of the invention, the advantages of embodiments of the present disclosure can be more readily determined by reading in conjunction with the accompanying drawings, which illustrate certain examples of embodiments of the present disclosure:

[0016] Figure 1A A simplified cross-sectional schematic diagram of a prior art structure including multiple vertical grooves is shown;

[0017] Figure 1B This shows the process after a gap-filling membrane is formed within the vertical trench. Figure 1A A simplified cross-sectional schematic diagram of the existing technology structure;

[0018] Figure 2 An exemplary process flow is shown, illustrating a method for forming a polycrystalline molybdenum film on a substrate surface according to embodiments of the present disclosure;

[0019] Figure 3 An exemplary process flow is shown, illustrating a first cyclic deposition process for directly depositing a nucleation film onto an exposed surface of a substrate according to embodiments of the present disclosure.

[0020] Figure 4 An exemplary process flow is shown, which demonstrates a second cyclic deposition process for directly depositing a polycrystalline molybdenum film onto a nucleation film according to embodiments of the present disclosure.

[0021] Figure 5A A simplified cross-sectional schematic diagram of a structure including a substrate with multiple non-planar features is shown;

[0022] Figure 5B This illustrates the process of directly depositing a nucleation film onto the exposed surface of a substrate according to embodiments of the present disclosure. Figure 5A A simplified cross-sectional diagram of the structure; and

[0023] Figure 5C The following is illustrated in an embodiment of the present disclosure after a polycrystalline molybdenum film is directly deposited on a nucleation film. Figure 5B A simplified cross-sectional diagram of the structure. Detailed Implementation

[0024] Although certain embodiments and examples are disclosed below, those skilled in the art will understand that the invention extends beyond the specific embodiments and / or uses disclosed herein, as well as obvious modifications and equivalents thereof. Therefore, it is intended that the scope of the invention be limited not to the specific disclosed embodiments described below.

[0025] Furthermore, the illustrations presented herein are not intended to be actual views of any particular material, structure, or device, but are merely idealized representations used to describe embodiments of this disclosure.

[0026] As used herein, the term “substrate” can refer to any one or more underlying materials that can be used or on which structures, devices, circuits, or films can be formed.

[0027] As used herein, the term “cyclic deposition” can refer to the sequential introduction of one or more precursors (reactants) into a reaction chamber to deposit a film over a substrate and includes deposition techniques such as atomic layer deposition and cyclic chemical vapor deposition.

[0028] As used herein, the term “cyclic chemical vapor deposition” can refer to any process in which a substrate is sequentially exposed to two or more volatile precursors, which react and / or decompose on the substrate to deposit the desired film.

[0029] As used herein, the term "atomic layer deposition" (ALD) can refer to a vapor-phase deposition process in which deposition cycles, preferably multiple consecutive deposition cycles, are performed in a reaction chamber. Typically, during each deposition cycle, a precursor is chemisorbed onto the deposition surface (e.g., a substrate surface or a previously deposited lower layer surface, such as material from a previous ALD deposition cycle), thereby forming a monolayer or sub-monolayer that is not readily reacting with additional precursors (i.e., a self-limiting reaction). Subsequently, if desired, a reactant (e.g., another precursor or reactive gas) can be subsequently introduced into the reaction chamber to convert the chemisorbed precursor into the desired material on the deposition surface. Typically, this reactant is capable of further reacting with the precursor. Furthermore, a purging step may be utilized during each deposition cycle to remove excess precursor and / or excess reactant and / or reaction byproducts from the reaction chamber after the conversion of the chemisorbed precursor. Furthermore, when performed using alternating pulses of precursor composition, reactant gas, and purge gas (e.g., inert carrier gas), the term "atomic layer deposition" as used herein is also intended to include processes specified by related terms such as "chemical vapor deposition," "atomic layer epitaxy (ALE)," molecular beam epitaxy (MBE), gas source MBE or organometallic MBE, and chemical beam epitaxy.

[0030] As used herein, the term "membrane" can refer to any physically continuous or discontinuous structure and material formed or deposited by the methods disclosed herein. For example, a "membrane" can include 2D materials, nanolaminates, nanorods, nanotubes, nanoparticles, partial or complete molecular layers, partial or complete atomic layers, or clusters of atoms and / or molecules. A "membrane" can also contain materials or layers with pinholes, but still remain at least partially continuous.

[0031] As used herein, the term "molybdenum halide precursor" may refer to a reactant that contains at least a molybdenum component and a halide component, wherein the halide component may include one or more of a chlorine component, an iodine component, or a bromine component.

[0032] As used herein, the term "molybdenum oxyhalide" may refer to a reactant comprising at least a molybdenum component, an oxygen component, and a halogen component.

[0033] As used in this article, the term "reducing agent" can refer to a reactant that donates electrons to another species in a redox chemical reaction.

[0034] As used herein, the term "polycrystalline film" can refer to a film exhibiting at least a short-range order of crystalline structure, and also includes the terms "multicrystalline film" or "polycrystal film". "Polycrystalline film" can also refer to a film comprising multiple microcrystals.

[0035] As used herein, the terms “amorphous” and “amorphous film” can refer to films that do not substantially exhibit an ordered structure.

[0036] As used herein, the term “crystal size” can refer to the average size of multiple crystallites within a polycrystalline film, as determined by X-ray diffraction (XRD) measurements of the polycrystalline film.

[0037] As used herein, the term "nonplanar feature" may refer to an opening or cavity disposed between two opposing surfaces of a nonplanar substrate, and may include "vertical nonplanar features" and "horizontal nonplanar features".

[0038] As used herein, the term "vertical nonplanar feature" can include: an opening or cavity disposed between opposing inclined sidewalls of two protrusions extending upward from a substrate surface, or opposing inclined sidewalls extending downward into a recess in the substrate surface. Non-limiting examples of "vertical nonplanar feature" may include, but are not limited to: V-shaped vertical trenches, tapered vertical trenches, concave vertical trenches, vertical openings, vertical gaps, and vertical silicon via trenches. For example, a vertical nonplanar feature may include adjacent sidewalls joined at a point at a feature base, or a vertical nonplanar feature may include a feature base flush with a flat substrate surface. As used herein, "vertical" does not specifically limit the slope of opposing sidewalls to being perpendicular to the horizontal plane of the substrate.

[0039] As used herein, the term "horizontal nonplanar feature" may include: an opening or cavity disposed between two substantially horizontal opposing surfaces that define the "horizontal nonplanar feature".

[0040] As used herein, the term "line bending" can refer to a bending or deformation of a substrate region disposed between adjacent nonplanar features, which is caused by the formation of a gap-fill film within the nonplanar features. For example, a nonplanar substrate may include multiple "vertical nonplanar features," such as vertical trenches, extending downward into the substrate. The region between adjacent "vertical nonplanar features" can be referred to as a line feature. When a gap-fill metal is formed within a substrate comprising multiple nonplanar features, the line feature may undergo line bending (i.e., deformation).

[0041] Reference to the concept of "line bending" Figure 1A Let's go to B for a more detailed explanation. Figure 1A Section B illustrates a prior art method for forming a gap-filling film within multiple non-planar features.

[0042] In more detail, Figure 1A A simplified cross-sectional schematic diagram of structure 100 before the gap-filling process is shown. Structure 100 includes a substrate 102 comprising an array of non-planar features 104, which in this example include vertical trenches disposed within the substrate 102. A plurality of line features 106 are disposed between each adjacent vertical trench 104. The plurality of line features 106 may have a substantially regular spacing (x), wherein the spacing (x) can be defined as the distance between the intermediate vertical axis of a line feature (e.g., axis 108A) and the intermediate vertical axis of an adjacent line feature (e.g., axis 108B). Figure 1A The array of vertical grooves 104 shown may include sloping sidewalls, wherein the width of each vertical groove decreases from the top / opening of the vertical groove to the base of the vertical groove. The width (y) of each groove in the array of vertical grooves can be determined by measuring the distance between the opposite sidewalls of the vertical grooves. For example, in Figure 1A In structure 100, the vertical grooves comprise V-shaped vertical grooves, wherein the (y) of each V-shaped groove can be determined by measuring the distance between the uppermost extents of the opposite sidewalls, such as... Figure 1A As shown in the image.

[0043] As a non-limiting example, before filling the deposition gaps with a film, Figure 1A Structure 100 may include a portion of a partially fabricated dynamic random access memory (DRAM) device structure, wherein the partially fabricated DRAM device structure includes a regular array of buried word line (bWL) trenches (e.g., vertical trench 104) and DRAM word lines (e.g., line features 106).

[0044] Figure 1B A simplified cross-sectional schematic diagram of the prior art structure 110 is shown, which includes structure 100 after depositing a gap-filling film within a vertical trench array. Figure 1A (of which), thus the vertical grooves are filled with a gap-filling membrane. For example... Figure 1B As shown, due to the deposition of the gap-filling film 112, the line features 106 disposed between adjacent vertical trenches 104 will bend (or deform), and the previously regular array of line features 106 will become more disordered due to the deposition of the gap-filling film. The bending of the line features 106 leads to an increase in the variation of the width of the vertical non-planar structure 104, as represented by the width (z), for example, as in Figure 1B The measurement is taken at the uppermost part of the V-shaped vertical groove.

[0045] As used herein, the term "line bend percentage" quantifies the degree of line bend caused by the deposition of a gap-filling film on a substrate comprising a regular array of nonplanar and linear features. The line bend percentage can be calculated using the following equation (I):

[0046]

[0047] The offset is calculated by the following equation (II):

[0048]

[0049] In other words, the offset value is equal to the absolute value of the average width of the non-planar features (e.g., vertical trenches) before gap-filling film deposition (the average of (z)) minus the average of the average widths (y) of the non-planar features (e.g., vertical trenches) before gap-filling film deposition. As a non-limiting example, the offset can be statistically determined by measuring the widths (y) of multiple non-planar features before gap-filling film deposition and subsequently measuring the widths (z) of multiple non-planar features after gap-filling film deposition in the non-planar features. The average of (z) and the average of (y) can be determined using high-magnification microscopy techniques such as scanning electron microscopy.

[0050] As used herein, the term "seam" can refer to a line or one or more macroscopic voids formed by the abutment of the leading edges of a gap-filling film. For example, a seam can refer to the region in a metallic gap-filling film where the leading edges of two metal films grown on opposite sidewalls of a non-planar feature come into contact with each other. Therefore, "seams" are generally located at the center of a metallic non-planar feature. The formation of seams in metallic gap-filling films is undesirable and can lead to poor device performance and subsequent problems in device fabrication. The presence of "seams" within a gap-filling film can be observed using scanning transmission electron microscopy (STEM) or transmission electron microscopy (TEM).

[0051] Although many exemplary materials are given throughout the various embodiments of this disclosure, it should be noted that the chemical formulas given for each of these exemplary materials should not be construed as limiting, and the exemplary materials given should not be limited by the given example stoichiometry.

[0052] This disclosure includes a method for forming a polycrystalline molybdenum film on a substrate surface using intermediate nucleation. Polycrystalline molybdenum films can be used in many applications, such as low-resistivity metal gap-filling films, padding layers for 3D-NAND, DRAM word line features, or as interconnect materials in CMOS logic circuit applications. The ability to deposit a polycrystalline molybdenum film on a substrate surface using an intermediate nucleation film (i.e., without using a high-resistivity padding layer) allows interconnects in logic circuit applications (i.e., CMOS structures) and word lines / bit lines in memory applications (e.g., 3D-NAND structures and DRAM structures) to have lower resistivity.

[0053] Furthermore, embodiments of this disclosure can provide nucleation films for depositing polycrystalline molybdenum films, wherein the nucleation film can improve the quality of the polycrystalline molybdenum film. For example, depositing a nucleation film prior to depositing a polycrystalline molybdenum film can produce a polycrystalline molybdenum film with reduced surface roughness and / or reduced crystallite size. The improved properties of the polycrystalline molybdenum film formed according to embodiments of this disclosure can improve the interstitial metal filling film and reduce the line curvature percentage of structures including arrays of nonplanar features and line features.

[0054] Therefore, embodiments of this disclosure may include a method for depositing a polycrystalline molybdenum film on a substrate surface using an intermediate nucleation film. The method of this disclosure may include: providing a substrate into a reaction chamber; depositing a nucleation film directly onto an exposed surface of the substrate, wherein the nucleation film comprises one of a metal oxide nucleation film or a metal nitride nucleation film; and depositing a polycrystalline molybdenum film directly onto the nucleation film, wherein the polycrystalline molybdenum film comprises a plurality of molybdenum crystallites having an average crystallite size of less than 80 Å.

[0055] refer to Figure 2This illustrates an exemplary process for forming a polycrystalline molybdenum film on a substrate surface using an intermediate nucleation film. Exemplary Process 200 ( Figure 2 It can include two different deposition processes: a first deposition process for directly depositing a nucleation film on the exposed surface of the substrate, and a second deposition process for directly depositing a polycrystalline molybdenum film on the nucleation film.

[0056] More details and reference Figure 2 Exemplary process 200 can be initiated by means of process frame 210, which includes providing a substrate into a reaction chamber.

[0057] In some embodiments of this disclosure, the substrate may comprise a nonplanar substrate including a plurality of nonplanar features, as previously described herein. It should be noted that embodiments of this disclosure are not limited to metal gap-filling methods for filling vertical and / or horizontal nonplanar features, and other geometries of nonplanar features disposed in and / or on the substrate can be filled with polycrystalline molybdenum films using the processes disclosed herein.

[0058] In some embodiments, the non-planar substrate may comprise one or more materials and material surfaces, including but not limited to semiconductors, dielectrics, and metal particles.

[0059] In some embodiments, the substrate may include a semiconductor material and a surface, such as, but not limited to, silicon (Si), germanium (Ge), germanium-tin (GeSn), silicon-germanium (SiGe), silicon-germanium-tin (SiGeSn), silicon carbide (SiC), or group III-V semiconductor materials.

[0060] In some embodiments, the substrate may include a metallic material and a surface, such as, but not limited to, pure metals, metal nitrides, metal carbides, metal borides, and mixtures thereof.

[0061] In some embodiments, the substrate may include a dielectric material and a surface, such as, but not limited to, silicon-containing dielectric materials and metal oxide dielectric materials. In some embodiments, the silicon-containing dielectric material may comprise one or more of the following: silicon dioxide (SiO2), low-oxide silicon, silicon nitride (Si3N4), silicon oxynitride (SiON), silicon oxycarbide (SiOC), silicon oxycarbonide (SiOCN), and silicon carbonitride (SiCN). In some embodiments, the metal oxide dielectric material may comprise one or more of the following: aluminum oxide (Al2O3), hafnium oxide (HfO2), tantalum oxide (Ta2O5), zirconium oxide (ZrO2), titanium oxide (TiO2), and hafnium silicate (HfSiO2). x ) and lanthanum oxide (La2O3).

[0062] In some embodiments of this disclosure, the substrate may comprise an engineered substrate in which a semiconductor layer is disposed above a body support and therein is an embedded oxide (BOX).

[0063] In some embodiments, the substrate utilized in the methods described herein may include device structures, including device structures formed in or partially fabricated on the surface of the substrate. For example, the substrate may contain fabricated and / or partially fabricated device structures, such as transistors and memory elements. In some embodiments, the substrate may contain a single-crystal surface and / or one or more subsurfaces, said subsurfaces may include non-single-crystal surfaces, such as polycrystalline surfaces and / or amorphous surfaces.

[0064] The substrate may be loaded into a reaction chamber configured to form a polycrystalline molybdenum film. In some embodiments, a nucleus film may be directly deposited on the exposed surface of the substrate using one or more deposition processes, including but not limited to chemical vapor deposition (CVD), immersion deposition, plasma-enhanced chemical vapor deposition (PECVD), or physical vapor deposition (PVD). In a particular embodiment of this disclosure, a first cycle deposition process may be used to deposit the nucleus film.

[0065] In some embodiments, a polycrystalline molybdenum film can be directly deposited on the nucleation film using deposition processes including, but not limited to, chemical vapor deposition (CVD), immersion deposition, plasma-enhanced chemical vapor deposition (PECVD), or physical vapor deposition (PVD). In a specific embodiment of this disclosure, a second-cycle deposition process can be used to deposit the polycrystalline molybdenum film.

[0066] In some embodiments, nucleation films and polycrystalline molybdenum films can be deposited using cyclic deposition processes due to the inherent conformality and achievable stepped coverage of the cyclic deposition process, especially when depositing films on non-planar substrates with high aspect ratio features.

[0067] The reactor and associated reaction chamber capable of forming the polycrystalline molybdenum film of this disclosure can be configured to perform a cyclic deposition process, such as atomic layer deposition (ALD) or cyclic chemical vapor deposition (CCVD). Therefore, in some embodiments, the reactor suitable for performing embodiments of this disclosure may include an ALD reactor configured to provide precursors and a CVD reactor. According to some embodiments, a nozzle reactor may be used. According to some embodiments, cross-flow, batch, small-batch, or space ALD reactors may be used.

[0068] In some embodiments of this disclosure, a batch reactor may be used. In some embodiments, a vertical batch reactor may be used. For example, a vertical batch reactor may include a reaction chamber and a lift constructed and arranged to move a boat configured to support a batch of 10 to 200 substrates in or outside the reaction chamber. In other embodiments, the batch reactor includes a small-batch reactor configured to accommodate 10 or fewer wafers, 8 or fewer wafers, 6 or fewer wafers, 4 or fewer wafers, or 2 or fewer wafers. In some embodiments where a batch reactor is used, the inter-wafer inhomogeneity is less than 3% (1σ), less than 2%, less than 1%, or even less than 0.5%.

[0069] The exemplary processes for forming polycrystalline molybdenum as described herein can optionally be performed in reactors and associated reaction chambers connected to a clustering tool. In a clustering tool, because each reaction chamber is dedicated to a specific process type, the temperature of the reaction chamber in each module can be kept constant, which increases productivity compared to reaction chambers where the substrate is heated to process temperature before each run. Additionally, the time required to pump the reaction chamber pressure to the required process pressure between substrates can be reduced in a clustering tool. In some embodiments, the exemplary processes disclosed herein can be performed in a clustering tool comprising multiple reaction chambers, wherein each individual reaction chamber can be used to expose the substrate to a separate reactant, and the substrate can be transferred between different reaction chambers to expose to multiple reactants, the transfer of the substrate being performed in a controlled environment to prevent contamination of the substrate and the film deposited thereon. For example, the deposition of a nucleation film can be performed via a cyclic deposition process in a first reaction chamber associated with the clustering tool, while the deposition of a polycrystalline molybdenum film can be performed via a cyclic deposition process in a second reaction chamber associated with the same clustering tool, wherein the transfer between the first and second reaction chambers occurs in a controlled environment to prevent contamination. In some embodiments of this disclosure, the process of this disclosure can be performed in a cluster tool comprising multiple reaction chambers, wherein each individual reaction chamber can be configured to heat the substrate to a different temperature.

[0070] In some embodiments, the deposition process of this disclosure can be performed in a single, independent reactor, which may be equipped with a loading lock. In such embodiments, it is not necessary to cool the reaction chamber between each run. For example, the single, independent reactor may be configured to deposit both core films and polycrystalline films, thereby eliminating the need to transfer the substrate between two or more reaction chambers.

[0071] Once the substrate is loaded into a suitable reaction chamber, such as one configured for a cyclic deposition process, the exemplary process 200 for forming a polycrystalline molybdenum film can proceed via process frame 220. Figure 2The process framework includes depositing a nucleation film directly onto an exposed surface of a substrate, wherein the nucleation film comprises one of a metal oxide nucleation film or a metal nitride nucleation film. (See reference...) Figure 3 The process block 220 and the subprocesses constituting the process block are described in more detail. The figure illustrates an exemplary first cycle deposition process for depositing a nucleation film directly onto the exposed surface of a substrate.

[0072] More specifically, the first cycle deposition process for directly depositing the nucleation film onto the exposed surface of the substrate (i.e., Figure 3 Process 220 can be continued by means of a subprocess block 310, which includes heating the substrate to the desired deposition temperature, i.e., the substrate temperature. For example, the substrate can be heated to a deposition temperature below approximately 800°C, or below approximately 700°C, or below approximately 600°C, or below approximately 500°C, or below approximately 400°C, or below approximately 300°C, or even below approximately 200°C. In some embodiments of this disclosure, the substrate temperature during the first cycle deposition process can be between 250°C and 800°C, or between 300°C and 600°C, or between 550°C and 600°C.

[0073] In some embodiments, the deposition temperature for depositing the nucleation film may depend on the composition of the nucleation film being deposited. For example, in some embodiments of this disclosure, the nucleation film may comprise a metal oxide nucleation film, including but not limited to alumina nucleation films, molybdenum oxide nucleation films, tungsten oxide nucleation films, ruthenium oxide nucleation films, rhenium oxide nucleation films, or iridium oxide nucleation films. In such example embodiments, the substrate temperature during the deposition of the metal oxide nucleation film may be below about 800°C, or below about 600°C, or below about 500°C, or below about 400°C, or even below about 300°C. In some embodiments, the substrate temperature during the deposition of the metal oxide nucleation film may be between 250°C and 550°C.

[0074] In some embodiments, the nucleation film may comprise a metal nitride nucleation film. For example, the metal nitride nucleation film may comprise a molybdenum nitride nucleation film. In such example embodiments, the substrate temperature during the deposition of the molybdenum nitride nucleation film may be below about 700°C, or below about 600°C, or below about 500°C, or below about 400°C, or even below about 300°C, or even below about 200°C. In some embodiments, the substrate temperature during the deposition of the molybdenum nitride nucleation film may be between 200°C and 700°C, or between 350°C and 600°C, or even between 450°C and 550°C.

[0075] Furthermore, in order to achieve the desired deposition temperature (i.e., the desired substrate temperature), an exemplary first cycle deposition of process frame 220 ( Figure 3 The pressure within the reaction chamber can also be adjusted during the cyclic deposition process to obtain a nucleated film with desired properties. For example, in some embodiments of this disclosure, an exemplary first cyclic deposition process of process block 220 ( Figure 3 The deposition can be carried out in a reaction chamber where the pressure is adjusted to less than 300 Torr, or less than 200 Torr, or less than 100 Torr, or less than 50 Torr, or less than 25 Torr, or less than 15 Torr, or even less than 2 Torr. In some embodiments, the pressure in the reaction chamber during the deposition of the nucleation film can be adjusted to a pressure between 2 Torr and 300 Torr, or between 30 Torr and 80 Torr.

[0076] Once the substrate has been heated to the desired temperature and the pressure in the reaction chamber has been adjusted to the desired level, the exemplary first cycle deposition process of process frame 220 can continue by means of a first cycle deposition stage 305, which may include an atomic layer deposition (ALD) process or a cycle chemical vapor deposition (CCVD) process.

[0077] Non-limiting example embodiments of cyclic deposition processes may include atomic layer deposition (ALD), where ALD is based on typically self-limiting reactions, in which approximately one atomic (or molecular) monolayer is deposited in each cell using sequential and alternating pulses of reactants. Deposition conditions and precursors are typically selected to provide a self-saturating reaction, such that an adsorbed layer of one reactant leaves a surface termination state unreacted to the gaseous reactants of the same reactant. Subsequently, the substrate is brought into contact with different reactants, which react with the previous termination state to achieve continued deposition. Thus, each cycle of alternating pulses typically leaves no more than approximately one monolayer of the desired material. However, as mentioned above, those skilled in the art will recognize that, for example, despite the alternating nature of the process, more than one monolayer of material can be deposited in one or more ALD deposition cycles if some gaseous reactions occur.

[0078] In some embodiments, a first cycle deposition process (e.g., an ALD deposition process) can be used to deposit a nucleation film. For example, the first cycle deposition process may include performing a first cycle deposition stage 305 (… Figure 3 One or more first-unit deposition cycles.

[0079] In some embodiments of this disclosure, the first unit deposition cycle of the first cyclic deposition stage 305 may include: exposing the substrate to a first gaseous reactant, removing any unreacted first gaseous reactant and reaction byproducts from the reaction chamber, and exposing the substrate to a second gaseous reactant, followed by a second removal step. In some embodiments of this disclosure, the first gaseous reactant may contain a metal precursor, and the second gaseous reactant may contain either a nitrogen precursor or an oxygen precursor.

[0080] In some embodiments, the precursors can be separated by an inert gas such as argon (Ar) or nitrogen (N2) to prevent gas-phase reactions between reactants and to achieve a self-saturating surface reaction. However, in some embodiments, the substrate can be moved to contact the first and second gas-phase reactants separately. Because the reaction is self-saturating, strict temperature control of the substrate and precise dosage control of the precursors may not be necessary. However, the substrate temperature is preferably such that any accompanying gaseous species neither condense into a monolayer nor decompose on the surface. Before contacting the substrate with the next reactant, any remaining precursors and reaction byproducts (if present) are removed from the substrate surface, such as by purging the reaction chamber or by moving the substrate. Undesirable gaseous molecules can be effectively removed from the reaction chamber by means of an inert purge gas. A vacuum pump can be used to assist in purging the reaction chamber.

[0081] According to some non-limiting embodiments of this disclosure, the ALD process can be used to deposit nucleation films directly on the exposed surface of a substrate. In some embodiments of this disclosure, the cyclic deposition stage 305 of the ALD process for depositing nucleation films may include a first unit deposition, which may include two distinct deposition stages. In the first stage of the first unit deposition cycle, the substrate may be contacted with a metal precursor to form no more than about one monolayer reactant species on the substrate surface. In the second stage of the first unit deposition cycle, the substrate may be contacted with either a nitrogen precursor or an oxygen precursor.

[0082] Therefore, in some embodiments, the first cycle deposition stage 305 of the first cycle deposition process 220 ( Figure 3 The process can continue using a subprocess frame 320, which includes contacting the substrate with a first gaseous reactant, and in a particular embodiment, contacting the substrate with a first gaseous reactant containing a metal precursor.

[0083] In some embodiments, the nucleation film may comprise a metal oxide nucleation film. For example, the metal oxide nucleation film may comprise at least one of the following: aluminum oxide nucleation film, molybdenum oxide nucleation film, tungsten oxide nucleation film, ruthenium oxide nucleation film, rhenium oxide nucleation film, or iridium oxide nucleation film.

[0084] In some embodiments, the nucleation film may comprise an alumina nucleation film, and in such embodiments, the metal precursor, i.e. the aluminum precursor, may comprise at least one of the following: trimethylaluminum (TMA), triethylaluminum (TEA), dimethylaluminum hydride (DMAH), tri-tert-butylaluminum (TTBA), aluminum trichloride (AlCl3), or dimethylaluminum isopropoxide (DMAI).

[0085] In some embodiments, the nucleation film may comprise a tungsten oxide nucleation film, and in such embodiments, the metal precursor, i.e., the tungsten precursor, may comprise a metal-organic tungsten precursor. In some embodiments, the metal-organic tungsten precursor may comprise a cyclopentadienyl tungsten compound, a tungsten β-diketone compound, a tungsten alkylamine compound, an amidoyltungsten compound, or other metal-organic tungsten compounds. In some embodiments, the metal-organic tungsten precursor may comprise bis(tert-butylimino)bis(tert-butylamino)tungsten (VI), bis(isopropylcyclopentadienyl)tungsten (IV) dihydrogenide, or tetracarbonyl(1,5-cyclooctadiene)tungsten (O).

[0086] In some embodiments, the nucleation film may comprise a ruthenium oxide nucleation film, and in such embodiments, the metal precursor, i.e. the ruthenium precursor, may comprise at least one of the following: ruthenium tetroxide (RuO)4, bis(cyclopentadienyl)ruthenium(II), bis(ethylcyclopentadienyl)ruthenium(II), and dodecacarbonyltriruthenium.

[0087] In some embodiments, the nucleation film may comprise a rhenium oxide nucleation film, and in such embodiments, the metal precursor, i.e., the rhenium precursor, may comprise at least one of the following: a rhenium halide precursor, a rhenium halide precursor, an alkyl rhenium oxide precursor, a cyclopentadienyl-based rhenium precursor, or a carbonyl rhenium halide precursor. Further information relating to rhenium precursors is described in U.S. Patent Application No. 16 / 219,555, entitled “Method for Forming Rhenium-Containing Films on a Substrate by Cyclic Deposition Process and Related Semiconductor Device Structures,” the entire contents of which are incorporated herein by reference.

[0088] In some embodiments, the nucleation membrane may comprise an iridium oxide nucleation membrane, and in such embodiments, the metal precursor, i.e. the iridium precursor, may comprise at least one of the following: 1,5-cyclooctadiene (acetylacetonate)iridium (I), 1,5-cyclooctadiene (hexafluoroacetylacetonate)iridium (I), 1-ethylcyclopentadienyl-1,3-cyclohexadiene iridium (I), acetylacetonate iridium (II), (methylcyclopentadienyl)(1,5-cyclooctadiene)iridium (I), and tris(norbornadiene)(acetylacetonate)iridium (III).

[0089] In some embodiments, the nucleation film may comprise a molybdenum oxide nucleation film, and in such embodiments, the metal precursor, i.e., the molybdenum precursor, may comprise a molybdenum halide precursor. In some embodiments, the molybdenum halide precursor may comprise a molybdenum chloride precursor, a molybdenum iodide precursor, or a molybdenum bromide precursor. As a non-limiting example, the molybdenum halide precursor may comprise at least one of the following: molybdenum pentachloride (MoCl5), molybdenum hexachloride (MoCl6), molybdenum hexafluoride (MoF6), molybdenum triiodide (MoI3), or molybdenum dibromide (MoBr2). In some embodiments, the molybdenum halide precursor may comprise a molybdenum chalcogenide, and in certain embodiments, the molybdenum halide precursor may comprise a chalcogenide molybdenum halide. For example, a chalcogenide molybdenum halide precursor may comprise a molybdenum halide selected from the group consisting of molybdenum oxychloride, molybdenum oxyiodide, or molybdenum oxybromide. In specific embodiments of this disclosure, the molybdenum halide precursor may comprise molybdenum oxychloride, including (but not limited to) molybdenum trichloride (V) (MoOCl3), molybdenum tetrachloride (VI) (MoOCl4), or molybdenum dichloride (IV) (MoO2Cl2).

[0090] In alternative embodiments, the molybdenum precursor may comprise a metal-organic molybdenum precursor, such as Mo(CO)6, Mo(tBuN)2(NMe2)2, Mo(NBu)2(StBu)2, (Me2N)4Mo, and (iPrCp)2MoH2.

[0091] In some embodiments, the nucleation film may comprise a metal nitride nucleation film. For example, the metal nitride nucleation film may comprise a molybdenum nitride nucleation film. In such embodiments where the metal nitride nucleation film comprises a molybdenum nitride nucleation film, the metal precursor, i.e., the molybdenum precursor, may comprise molybdenum halide, examples of which have been previously described herein. In specific embodiments of this disclosure, the molybdenum precursor may comprise molybdenum oxychloride, including (but not limited to) molybdenum trichloride (V) (MoOCl3), molybdenum tetrachloride (VI) (MoOCl4), or molybdenum dichloride (IV) (MoO2Cl2). In alternative embodiments, the molybdenum precursor may comprise an organometallic molybdenum as previously described herein.

[0092] In some embodiments, the nucleation film may comprise a metal silicide nucleation film or a metal boride nucleation film, such as a molybdenum silicide nucleation film or a molybdenum boride nucleation film. For example, the metal silicide nucleation film may be deposited using a silicon-containing precursor, such as silane (SiH4), disilane (Si2H6), propane (Si3H8), or butane (Si4H6). 10 ) or has a general empirical Si x H (2x+2) More advanced silanes. In additional instances, metal boride nucleation films can be deposited using boron-containing precursors, such as borane (BH3), diborane (B2H6), or other boranes, such as decaborane (B2H6). 10 H14 ).

[0093] In some embodiments, contacting the substrate with the metal precursor can include a time period between about 0.1 seconds and about 60 seconds, or between about 0.1 seconds and about 10 seconds, or between about 0.5 seconds and about 5.0 seconds. Additionally, during the contact between the substrate and the metal precursor, the flow rate of the metal precursor can be less than 1000 sccm, or less than 500 sccm, or less than 100 sccm, or less than 10 sccm, or even less than 1 sccm. Furthermore, during the contact between the substrate and the metal precursor, the flow rate of the metal precursor can be in the range of about 1 to 2000 sccm, about 5 to 1000 sccm, or about 10 to about 500 sccm.

[0094] The first cycle deposition process 220, first cycle deposition stage 305 ( Figure 3 The reaction can be continued by purging the reaction chamber. For example, excess metal precursors and reaction byproducts (if any) can be removed from the substrate surface, for instance, by pumping with an inert gas. In some embodiments of this disclosure, the purging process may comprise a purging cycle in which the substrate surface is purged for a period of less than about 5.0 seconds, or less than about 3.0 seconds, or even less than about 2.0 seconds. Excess metal precursors and any possible reaction byproducts can be removed by means of a vacuum generated by a pumping system in fluid communication with the reaction chamber.

[0095] After purging the reaction chamber with a purge cycle, the first cycle deposition stage 305 of the first cycle deposition process 220 ( Figure 3 The process can be continued by means of a subprocess frame 330, which includes contacting the substrate with a second gaseous reactant, particularly contacting the substrate with one of a nitrogen precursor or an oxygen precursor.

[0096] In some embodiments, the nucleation film may comprise a metal oxide nucleation film, and in such embodiments, the first gas-phase reactant may comprise a metal precursor and the second gas-phase reactant may comprise an oxygen precursor. In some embodiments, the nucleation film may comprise a metal nitride nucleation film, and in such embodiments, the first gas-phase reactant may comprise a metal precursor and the second gas-phase reactant may comprise a nitrogen precursor.

[0097] In embodiments of this disclosure employing metal oxide nucleation, the second gas-phase reactant may comprise one or more oxygen precursors selected from the group consisting of: water (H2O), hydrogen peroxide (H2O2), ozone (O3), or oxides of nitrogen, such as nitric oxide (NO), nitrous oxide (N2O), or nitrogen dioxide (NO2). As a further non-limiting example, the oxygen precursor may comprise: an organic alcohol, such as isopropanol, or an oxygen plasma, wherein the oxygen plasma may comprise: atomic oxygen, oxygen free radicals, and excited oxygen species.

[0098] In embodiments of this disclosure employing metal nitride nucleation, the second gas-phase reactant may comprise a nitrogen precursor. For example, the nitrogen precursor may comprise at least one of the following: ammonia (NH3), hydrazine (N2H4), triazine (N3H5), tert-butylhydrazine (C4H9N2H3), methylhydrazine (CH3NHNH2), dimethyl sulfide ((CH3)2N2H2), or a nitrogen plasma, wherein the nitrogen plasma comprises: atomic nitrogen, nitrogen radicals, and excited nitrogen species.

[0099] In some embodiments of this disclosure, contacting the substrate with a second gaseous reactant, i.e., an oxygen precursor or a nitrogen precursor, may include a contact time between about 0.01 seconds and about 120 seconds, about 0.05 seconds and about 60 seconds, or about 0.1 seconds and about 10 seconds. Additionally, during the contact between the substrate and the second gaseous reactant, the flow rate of the second gaseous reactant may be less than 10,000 sccm, less than 5,000 sccm, or even less than 100 sccm.

[0100] After contacting the substrate with either a nitrogen precursor or an oxygen precursor, the first cycle deposition stage 305 of process frame 220 ( Figure 3 The reaction can be continued by purging the reaction chamber. For example, as previously described herein, excess second gaseous reactants and reaction byproducts (if any) can be removed from the substrate surface.

[0101] After the second gaseous reactants and any reaction byproducts are completely purged from the reaction chamber, the first cycle deposition stage 305 of the first cycle deposition process 220 ( Figure 3 The process can proceed to decision gate 340, which depends on the desired average film thickness of the deposited nucleated film. For example, if the deposited thickness of the nucleated film is insufficient for the desired application, the cyclic deposition stage 305 can be repeated by returning to subprocess frame 320 and continuing with another first-unit deposition cycle. This first-unit deposition cycle may include contacting the substrate with a metal precursor (subprocess frame 320), purging the reaction chamber, contacting the substrate with either a nitrogen or oxygen precursor (subprocess frame 330), and purging the reaction chamber again. The first-unit deposition cycle of cyclic deposition stage 305 can be repeated one or more times until a nucleated film of the desired average thickness is deposited on the substrate. Once the nucleated film has been deposited to the desired average thickness, the first cyclic deposition process of process frame 220 can exit via subprocess frame 350, and the substrate on which the nucleated film has been deposited can undergo… Figure 2 Another process for forming polycrystalline molybdenum films 200.

[0102] It should be understood that in some embodiments of this disclosure, the sequence of contacting the substrate with the first gas-phase reactant (e.g., a metal precursor) and the second gas-phase reactant (e.g., a nitrogen precursor or an oxygen precursor) may be such that the substrate is first contacted with the second gas-phase reactant, and then with the first gas-phase reactant. Additionally, in some embodiments, the cyclic deposition stage 305 of the first cyclic deposition process 220 may include contacting the substrate with the first gas-phase reactant once or multiple times, and then contacting the substrate with the second gas-phase reactant once or multiple times. Furthermore, in some embodiments, the cyclic deposition stage 305 of the exemplary process 220 may include contacting the substrate with the second gas-phase reactant once or multiple times, and then contacting the substrate with the first gas-phase reactant once or multiple times.

[0103] In embodiments where the nucleation film comprises a molybdenum nitride film, the cyclic deposition stage 305 may additionally include contacting the substrate with a third gas-phase reactant containing a reducing agent. For example, the nitrogen precursor and reducing agent may be introduced into the reaction chamber simultaneously, or alternatively, the nitrogen precursor and reducing agent may be introduced into the reaction chamber separately, with or without a purge cycle. Further information regarding the method of depositing molybdenum nitride films is described in U.S. Application No. 62 / 891,254, entitled “Method for Depositing Molybdenum Nitride Films on a Substrate Surface by Cyclic Deposition Process and Related Semiconductor Device Structures” by Stevens et al., the entire contents of which are incorporated herein by reference.

[0104] In some embodiments, the first cyclic deposition process as described herein may comprise a hybrid ALD / CVD process or a cyclic CVD process. For example, in some embodiments, the deposition rate of the first cyclic deposition process (e.g., an ALD process) may be lower compared to the deposition rate of the CVD process. An exemplary method to increase the deposition rate of the first cyclic deposition process may be to operate at a higher substrate temperature than typically used in ALD processes, thereby producing some portions of the CVD process while still utilizing the sequential introduction of precursors; such a process may be referred to as cyclic CVD. In some embodiments, the cyclic CVD process may comprise the introduction of two or more precursors into a reaction chamber, wherein there may be overlapping time periods between the two or more precursors in the reaction chamber, thereby producing both ALD deposition components and CVD deposition components. For example, the cyclic CVD process may include a continuous flow of one precursor and a periodic pulse of a second precursor entering the reaction chamber.

[0105] In some embodiments of this disclosure, the nucleation film can be deposited directly on the exposed surface of the substrate at a growth rate of from about 0.05 Å / cycle to about 5 Å / cycle, or from about 0.1 Å / cycle to about 2 Å / cycle.

[0106] In some embodiments of this disclosure, the nucleation film can be deposited as a physically continuous film. For example, low-energy ion scattering (LEIS) can be used to determine the thickness that makes the film physically continuous. In some embodiments, a physically continuous nucleation film can be deposited to an average film thickness of less than 100 Å, or less than 50 Å, or less than 40 Å, or less than 30 Å, or less than 20 Å, or less than 10 Å, or even less than 5 Å. In some embodiments, a physically continuous nucleation film can be deposited to an average film thickness between approximately 5 Å and 50 Å.

[0107] In some embodiments of this disclosure, the nucleation film deposition is a physically discontinuous film having an average film thickness of less than 50 Å, or less than 40 Å, or less than 30 Å, or less than 20 Å, or less than 10 Å, or less than 5 Å, or less than 2 Å, or even less than 1 Å. In some embodiments, the physically discontinuous nucleation film can be deposited to an average film thickness between approximately 1 Å and 50 Å.

[0108] In some embodiments of this disclosure, the nucleation film can be deposited as an amorphous film. For example, the nucleation film may comprise one of an amorphous metal oxide film or an amorphous metal nitride film.

[0109] In some embodiments, the exposed surface of the substrate may include multiple non-planar features, such as vertical non-planar features and / or horizontal non-planar features. As a non-limiting example, the substrate surface may include multiple vertical trenches (e.g., V-shaped vertical trenches, or tapered vertical trenches), and the step coverage of the nucleation film deposited on the non-planar surface of the substrate may be greater than about 50%, or greater than about 80%, or greater than about 90%, or greater than about 95%, or greater than about 98%, or even greater than about 99%. In some embodiments, the non-planar features may include vertical non-planar features having an aspect ratio (e.g., the ratio of the height of the vertical trench to the width of the vertical trench), said aspect ratio being greater than 2:1, or greater than 5:1, or greater than 10:1, or greater than 25:1, or greater than 50:1, or even greater than 100:1, wherein “greater than” as used in such examples means that the height of the vertical non-planar feature is greater. In some embodiments, the substrate may include a plurality of horizontal non-planar features, wherein the horizontal non-planar features may have the following aspect ratio (height:width): greater than 1:2, or greater than 1:5, or greater than 1:10, or greater than 1:25, or greater than 1:50, or even greater than 1:100, wherein “greater than” as used in such instances means that the width of the horizontal non-planar features has a greater distance.

[0110] It should also be noted that the nucleation film of this disclosure does not constitute a barrier layer or barrier material commonly used in semiconductor device applications to prevent metal species from diffusing into the underlying dielectric material. The nucleation film of this disclosure is used to improve the material quality of the subsequently deposited polycrystalline molybdenum film and does not constitute a high resistivity barrier layer or barrier material used in common semiconductor device manufacturing processes.

[0111] In some embodiments, the nucleation film of this disclosure can improve subsequent processes for directly depositing polycrystalline molybdenum films on the nucleation film. For example, using the nucleation film before depositing the polycrystalline molybdenum film can increase the processability window for high-quality film deposition, i.e., the deposition process is insensitive to variability in process parameters (e.g., deposition temperature, pressure, pulse period, cycle time, etc.).

[0112] After directly depositing the nucleation film onto the exposed surface of the substrate, an exemplary polycrystalline molybdenum film formation process 200 ( Figure 2 The process can be continued using process frame 230, which includes depositing a polycrystalline molybdenum film directly onto the nucleation film.

[0113] More specifically, process block 230 for depositing a polycrystalline molybdenum film may include a second cycle deposition process. In some embodiments, process block 230 may employ alternative deposition methods as previously described herein. (Refer to...) Figure 4 The process block 230 and its associated sub-process blocks are described in more detail. The figure illustrates a second cycle deposition process for depositing polycrystalline molybdenum films.

[0114] In some embodiments, Figure 4 The second cycle deposition process 230 may comprise an atomic layer deposition process or a cyclic chemical vapor deposition process as previously described herein. As a non-limiting example, the second cycle deposition process 230 may comprise an ALD process, which may be initiated by means of a subprocess block 410, which includes heating the substrate to a desired deposition temperature. For example, the substrate may be heated to a substrate temperature below approximately 800°C, or below approximately 700°C, or below approximately 600°C, or below approximately 500°C, or below approximately 400°C, or below approximately 300°C, or even below approximately 200°C. In some embodiments of this disclosure, the substrate temperature during the second cycle deposition 230 may be between 200°C and 800°C, or between 300°C and 700°C, or between 400°C and 600°C, or between 500°C and 550°C.

[0115] Furthermore, to achieve the desired deposition temperature (i.e., the desired substrate temperature), the second cycle deposition process 230 can also adjust the pressure within the reaction chamber during the deposition process to obtain the desired properties of the deposited polycrystalline molybdenum film. For example, in some embodiments of this disclosure, the second cycle deposition process 230 can be performed in a reaction chamber adjusted to a pressure of less than 300 Torr, or less than 200 Torr, or less than 100 Torr, or less than 50 Torr, or less than 25 Torr, or even less than 10 Torr. In some embodiments, the pressure within the reaction chamber during deposition can be adjusted between 10 Torr and 300 Torr, or between 30 Torr and 80 Torr, or even equal to or greater than 30 Torr.

[0116] After heating the substrate to the desired deposition temperature and adjusting the pressure inside the reaction chamber, the second cycle deposition process 230 ( Figure 4 The process can continue with a second cycle deposition stage 405. The second cycle deposition stage 405 can be continued by means of a sub-process frame 420, which includes contacting the substrate with a third gas-phase reactant that may contain a molybdenum halide precursor.

[0117] In some embodiments, the molybdenum halide precursor may comprise a molybdenum chloride precursor, a molybdenum iodide precursor, or a molybdenum bromide precursor. For example, the molybdenum halide precursor may comprise one or more of the following: molybdenum pentachloride (MoCl5), molybdenum hexachloride (MoCl6), molybdenum hexafluoride (MoF6), molybdenum triiodide (MoI3), or molybdenum dibromide (MoBr2). In specific embodiments, the molybdenum halide precursor may comprise a molybdenum chloride precursor, such as molybdenum pentachloride (MoCl5) or molybdenum hexachloride (MoCl6).

[0118] In alternative embodiments, the molybdenum precursor may comprise a metal-organic molybdenum precursor, such as Mo(CO)6, Mo(tBuN)2(NMe2)2, Mo(NBu)2(StBu)2, (Me2N)4Mo, and (iPrCp)2MoH2.

[0119] In some embodiments, the molybdenum halide precursor may comprise a chalcogenide molybdenum halide precursor. For example, the chalcogenide molybdenum halide precursor may comprise molybdenum halide selected from the group consisting of molybdenum oxychloride, molybdenum oxyiodide, or molybdenum oxybromide. In specific embodiments of this disclosure, the molybdenum halide precursor may comprise molybdenum oxychloride, including but not limited to molybdenum trichloride (V) (MoOCl3), molybdenum tetrachloride (VI) (MoOCl4), or molybdenum dichloride (IV) (MoO2Cl2).

[0120] In some embodiments of this disclosure, the substrate may be in contact with the molybdenum halide precursor for a period of time between about 0.1 seconds and about 60 seconds, or between about 0.1 seconds and about 10 seconds, or between about 0.5 seconds and about 5.0 seconds. Furthermore, during the contact between the substrate and the molybdenum halide precursor, the flow rate of the molybdenum halide precursor may be less than 1000 sccm, or less than 500 sccm, or less than 100 sccm, or less than 10 sccm, or even less than 1 sccm. Additionally, during the contact between the substrate and the molybdenum halide precursor, the flow rate of the molybdenum precursor may be in the range of about 1 to 2000 sccm, about 5 to 1000 sccm, or about 10 to about 500 sccm.

[0121] The second cycle deposition process 230, second cycle stage 405 ( Figure 4 The reaction can be continued by purging the reaction chamber. For example, excess molybdenum halide precursors and reaction byproducts (if any) can be removed from the substrate surface, for instance, by pumping inert gas. In some embodiments of this disclosure, the purging process may comprise one or more purging cycles as previously described herein.

[0122] After purging the reaction chamber, a second cycle deposition 405 can continue by means of a subprocess frame 430, which includes contacting the substrate with a fourth gaseous reactant that may contain a reducing agent. For example, the reducing agent may contain at least one of the following: syngas (H2 + N2), ammonia (NH3), hydrazine (N2H4), alkyl hydrazine (e.g., tert-butylhydrazine (C4H4)). 12 The reducing agent may contain: N2), molecular hydrogen (H2), hydrogen atoms (H), hydrogen plasma, hydrogen radicals, hydrogen excited species, alcohols, aldehydes, carboxylic acids, boranes, or amines. In other examples, the reducing agent may contain at least one of the following: silane (SiH4), disilane (Si2H6), propane (Si3H8), germanane (GeH4), digermanane (Ge2H6), borane (BH3), or diborane (B2H6). In specific embodiments of this disclosure, the reducing agent may contain molecular hydrogen (H2).

[0123] In some embodiments of this disclosure, the substrate may be in contact with the reducing agent for a period of time between about 0.01 seconds and about 180 seconds, or between about 0.05 seconds and about 60 seconds, or between about 0.1 seconds and about 10.0 seconds. Furthermore, during the contact of the substrate with the reducing agent, the flow rate of the reducing agent may be less than 30 slm, or less than 15 slm, or less than 10 slm, or less than 5 slm, or less than 1 slm, or even less than 0.1 slm. Additionally, during the contact of the substrate with the reducing agent, the flow rate of the reducing agent may be in the range of about 0.1 to 30 slm, about 5 to 15 slm, or equal to or greater than 10 slm.

[0124] After the substrate is brought into contact with the reducing agent, the second cycle deposition stage 405 can be carried out by purging the reaction chamber, as previously described herein.

[0125] After the reducing agent (and any reaction byproducts) has been completely purged from the reaction chamber, the second cycle deposition stage 405 can proceed to decision gate 440, where decision gate 440 depends on the desired average thickness of the deposited polycrystalline molybdenum film. For example, if the average deposition thickness of the polycrystalline molybdenum metal is insufficient for the desired application, the cycle deposition stage 405 can be repeated by returning to subprocess box 420 and continuing with a second unit deposition cycle, where the second unit deposition cycle of the second cycle deposition process 230 may include contacting the substrate with the molybdenum halide precursor (subprocess box 420), purging the reaction chamber, contacting the substrate with the reducing agent (subprocess box 430), and purging the reaction chamber again. The second unit deposition cycle of cycle deposition stage 405 can be repeated one or more times until the desired average thickness of polycrystalline molybdenum metal is deposited directly on the nucleation film. Once the polycrystalline molybdenum film has been deposited to the desired average thickness, the second cycle deposition process 230 can exit via subprocess box 450.

[0126] After completing the process for depositing a polycrystalline molybdenum film (process block 230), an exemplary process 200 for forming a polycrystalline molybdenum film ( Figure 2 The process can end via process frame 240, where the substrate leaving the process and on which the polycrystalline molybdenum film is disposed can be further processed to manufacture a desired structure, such as a semiconductor device structure.

[0127] It should be understood that in some embodiments of this disclosure, the sequence of contact between the substrate and the molybdenum precursor and the reducing agent may be as follows: first, the substrate is contacted with the reducing agent, and then with the molybdenum precursor. Additionally, in some embodiments, the cyclic deposition stage 405 of the second cyclic deposition process 230 may include contacting the substrate with the molybdenum precursor once or multiple times, and then contacting the substrate with the reducing agent once or multiple times. Furthermore, in some embodiments, the cyclic deposition stage 405 of the second cyclic deposition process 230 may include contacting the substrate with the reducing agent once or multiple times, and then contacting the substrate with the molybdenum precursor once or multiple times.

[0128] In some embodiments, the second cycle deposition process 230 for depositing polycrystalline molybdenum films may include a hybrid ALD / CVD process or a cycle CVD process, as previously described herein.

[0129] The polycrystalline molybdenum film deposited by the methods disclosed herein can be a physically continuous film. In some embodiments, the polycrystalline molybdenum film can be physically continuous with an average film thickness of less than about 100 Å, or less than about 60 Å, or less than about 50 Å, or less than about 40 Å, or less than about 30 Å, or less than about 20 Å, or even less than about 10 Å.

[0130] In some embodiments of this disclosure, the polycrystalline molybdenum film may have an average film thickness of about 20 Å to 250 Å, or about 50 Å to 200 Å, or even about 100 Å to 150 Å. In some embodiments, the polycrystalline molybdenum film may have an average film thickness greater than about 20 Å, or greater than about 30 Å, or greater than about 40 Å, or greater than about 50 Å, or greater than about 60 Å, or greater than about 100 Å, or greater than about 250 Å, or even greater than about 500 Å. In some embodiments, the polycrystalline molybdenum film may have an average film thickness less than about 250 Å, or less than about 100 Å, or less than about 50 Å, or less than about 25 Å, or less than about 10 Å, or even less than about 5 Å. In some embodiments, the polycrystalline molybdenum film of this disclosure may have an average film thickness between about 100 Å and 250 Å.

[0131] In some embodiments, the polycrystalline molybdenum film may comprise a plurality of molybdenum crystallites (also referred to as molybdenum grains), wherein the plurality of molybdenum crystallites may comprise micron- or even nanon-scale regions of crystalline molybdenum forming the polycrystalline molybdenum film. In some embodiments, the molybdenum crystallites formed by the methods disclosed herein may have an average crystallite size of less than 100 Å, or less than 80 Å, or less than 60 Å, or less than 40 Å, or less than 20 Å, or even less than 10 Å. In some embodiments, the molybdenum crystallites may have an average crystallite size between about 10 Å and 100 Å, or between about 20 Å and 75 Å, or even between about 25 Å and 50 Å. As a non-limiting example, the polycrystalline molybdenum film may be deposited directly on a molybdenum nitride nucleation film and the molybdenum crystallites of the polycrystalline molybdenum metal may have an average crystallite size of less than about 60 Å, or less than about 50 Å, or even less than about 40 Å. The average size of the plurality of molybdenum crystallites may be determined by x-ray diffraction (XRD) measurements.

[0132] In some embodiments, the average crystallite size of the polycrystalline molybdenum film can be adjusted by changing the properties of the nucleating film below, such as surface roughness, composition, and average crystallite size.

[0133] In some embodiments, the use of an intermediate nucleation film can improve the surface roughness of the polycrystalline molybdenum film subsequently deposited directly on the nucleation film. For example, the polycrystalline molybdenum film formed according to embodiments of the present disclosure can have an rms surface roughness (Rm) of less than 5 Å, or less than 3 Å, or less than 2 Å, or even less than 1 Å. a In some embodiments, the RMS surface roughness (Rm) of the polycrystalline molybdenum film is... a It can be between approximately 1 Å and 10 Å, or between approximately 2 Å and 5 Å, or even between approximately 2 Å and 3 Å.

[0134] In some embodiments, the surface roughness of the polycrystalline molybdenum film can be expressed as a roughness percentage of the average total thickness of the polycrystalline molybdenum film. For example, the surface roughness percentage of the polycrystalline molybdenum film can be less than 10%, or less than 5%, or less than 3%, or even less than 1%. As a non-limiting example, the nucleation film can comprise a molybdenum nitride nucleation film having an average film thickness of approximately 20 Å, and the polycrystalline molybdenum film deposited directly on the molybdenum nitride nucleation can have an average film thickness of approximately 100 Å, wherein the polycrystalline molybdenum film has an rms surface roughness (Rm) of less than 4 Å. a (and less than 4% of the corresponding surface roughness percentage).

[0135] In some embodiments, the substrate may comprise a dielectric material, and the nucleation film may be deposited directly on the exposed surface of the dielectric material. In some embodiments, the substrate may comprise a metallic material, and the nucleation film may be deposited directly on the exposed surface of the metallic material. In some embodiments, the substrate may comprise a semiconductor material, and the nucleation film may be deposited directly on the exposed surface of the semiconductor material.

[0136] The embodiments of this disclosure, which employ an intermediate nucleation film between the substrate surface and the polycrystalline molybdenum film, can produce polycrystalline molybdenum films with a higher mass than those formed by directly depositing the polycrystalline molybdenum film on the exposed surface of the substrate (i.e., without employing an intermediate nucleation film).

[0137] As a non-limiting example, the exposed surface of the substrate may comprise an alumina (e.g., Al₂O₃) surface, and the molybdenum nitride nucleation film may be deposited directly on the exposed alumina surface, achieving an average nucleation film thickness of less than 25 Å. Following the deposition of the molybdenum nitride nucleation film, a polycrystalline molybdenum film may be deposited directly on top of the molybdenum nitride nucleation film. In such examples, the polycrystalline molybdenum film may have an rms surface roughness (Rm) of less than 5 Å, or less than 4 Å, or less than 3 Å, or even less than 2 Å. a Additionally, polycrystalline molybdenum films of this type can have a surface roughness percentage of less than 5%, or less than 4%, or less than 3%, or even less than 2%.

[0138] In some embodiments, the substrate may comprise a dielectric material, and the nucleation film may be deposited directly on the exposed surface of the dielectric material. In some embodiments, the substrate may comprise a semiconductor material, and the nucleation film may be deposited directly on the exposed surface of the semiconductor material. In some embodiments, the substrate may comprise a metallic material, and the nucleation film may be deposited directly on the exposed surface of the metallic material. In some embodiments, the nucleation film may be deposited directly on the exposed surface of a non-planar substrate, wherein the exposed surface may comprise one or more of a dielectric surface, a semiconductor surface, or a metallic surface. As a non-limiting example, the nucleation film may comprise a molybdenum nitride nucleation film deposited directly on one or more of a dielectric surface, a metallic surface, or a semiconductor surface.

[0139] In some embodiments, the polycrystalline molybdenum film directly disposed on the nucleation film constitutes a bilayer with low resistivity. For example, the bilayer formed according to embodiments of the present disclosure may have a resistivity of less than 50 μΩ-cm, or less than 30 μΩ-cm, or less than 20 μΩ-cm, or even less than 25 μΩ-cm, wherein the bilayer may comprise an average nucleation film thickness of less than 20 Å and an average polycrystalline molybdenum film thickness of less than 100 Å.

[0140] As a non-limiting example, the bilayer can be directly deposited on the dielectric material, i.e., directly deposited on the exposed surface of the dielectric material via a nucleation film, and the polycrystalline molybdenum film can be directly deposited on the nucleation film. In such examples, the bilayer can have a resistivity of less than 50 μΩ-cm, or less than 30 μΩ-cm, or less than 20 μΩ-cm, or even less than 25 μΩ-cm, wherein the bilayer can contain an average nucleation film thickness of less than 20 Å and an average polycrystalline molybdenum film thickness of less than 100 Å.

[0141] In some embodiments, the exposed surface of the nucleation film on which the polycrystalline molybdenum film is deposited may include multiple non-planar features, such as vertical non-planar features and / or horizontal non-planar features. As a non-limiting example, the surface of the nucleation film may include multiple vertical trenches (e.g., V-shaped vertical trenches, or conical vertical trenches), and the step coverage of the polycrystalline molybdenum film deposited directly on the non-planar surface of the nucleation film may be greater than about 50%, or greater than about 80%, or greater than about 90%, or greater than about 95%, or greater than about 98%, or even greater than about 99%. In some embodiments, the non-planar features of the nucleation film may include vertical non-planar features having an aspect ratio (e.g., the ratio of the height to the width of the vertical trenches) greater than 2:1, or greater than 5:1, or greater than 10:1, or greater than 25:1, or greater than 50:1, or even greater than 100:1, wherein “greater than” as used in such examples means that the height of the vertical non-planar feature is greater.

[0142] The polycrystalline molybdenum films formed by the deposition methods disclosed herein can be used in a wide range of applications. For example, applications may include (but are not limited to) logic and memory contact filling, DRAM buried word line (bWL) filling, vertically integrated memory gate / word line filling, and 3D-integrated processes such as through-silicon via filling. The molybdenum gap filling process disclosed herein can also be used to fill horizontally non-planar features, such as 3D-NAND word lines.

[0143] The deposition method and polycrystalline silicon molybdenum film disclosed herein are advantageous for the aforementioned example applications, and even in film applications, due to the low resistivity of the polycrystalline silicon molybdenum film. Current disadvantages of interstitial metal films, such as tungsten films, include: high-resistivity nucleation layers, high-resistivity barrier layers, and undesirable resistivity increases, as thinner nucleation and barrier layers are required as device feature sizes decrease. Replacing thin, high-resistivity films with the nucleation and polycrystalline molybdenum films disclosed herein can allow for reduced power losses and reduced heating in integrated circuit applications.

[0144] Another drawback of current interstitial metal filling processes and materials is the occurrence of "line bending," which can be observed, for example, in substrates with a large number of non-planar features with narrow spacing or in substrates with a large number of high aspect ratio non-planar features that are adjacent to each other (as referenced in this paper). Figure 1A -B as previously described. Significant line bending is observed in DRAM buried word line (bWL) structures when conventional metal films such as tungsten are used as gap fill materials for (bWL) trench structures. The presence of line bending during device fabrication can cause undesirable device non-uniformity and reduced device yield. Replacing conventional gap fill deposition processes and materials with the deposition process and nucleation film / polycrystalline molybdenum film disclosed herein can allow for a reduction or even elimination of line bending during device fabrication.

[0145] Reference Figure 5A -C indicates a non-limiting example of the application of this disclosure. Figure 5A This shows a substrate comprising numerous vertical non-planar features prior to the formation of the gap-filling metal. Figure 5B This illustrates the process after the nucleation film is directly deposited on the exposed surface of the substrate. Figure 5A The previous structure, and Figure 5C This shows the effect after a polycrystalline molybdenum film is directly deposited on a nucleation film. Figure 5B The previous structure.

[0146] In more detail, Figure 5AThe structure 500 shown may include a substrate 502 comprising a plurality of non-planar features, particularly a plurality of vertical non-planar features 504. For example, the plurality of vertical non-planar features 504 may comprise a large number of V-shaped vertical trenches disposed in the substrate 502. In some embodiments, the vertical non-planar features may comprise high aspect ratio features, which may have an aspect ratio (height:width) greater than 2:1, or greater than 5:1, or greater than 10:1, or greater than 25:1, or greater than 50:1, or even greater than 100:1. Figure 5A In the example shown, the width of the V-shaped vertical groove can be determined by measuring the distance between the uppermost extents of the opposite sidewalls of each V-shaped vertical groove.

[0147] In other applications, substrate 500 may include a plurality of alternative vertical nonplanar features as previously described herein, or a combination of various vertical nonplanar features and / or horizontal nonplanar features.

[0148] like Figure 5A As shown, a plurality of line features 506, such as protruding semiconductor or dielectric wires, or protruding semiconductor fin structures, are disposed between adjacent vertical non-planar features 504.

[0149] In some embodiments of this disclosure, the plurality of line features 506 may be arranged in a regular array. For example, the line features 506 may be arranged such that the spacing (x) between adjacent line features 500 is substantially uniform, wherein the spacing (x) may be defined as the distance between the middle vertical axis of a line feature (e.g., axis 508A) and the middle vertical axis of an adjacent line feature (e.g., axis 508B).

[0150] Furthermore, multiple vertical non-planar features 504 can have substantially uniform profiles and dimensions. For example, such as Figure 5A The illustrated vertical non-planar feature 504 includes a V-shaped vertical groove with sloping sidewalls, wherein the width of the V-shaped vertical groove decreases from the opening of the groove to the base of the groove. As a non-limiting example, a plurality of vertical non-planar features may contain substantially uniform widths (y), wherein the width of each feature in the array of vertical non-planar features can be determined by measuring the distance between each opening of the vertical non-planar feature, i.e., measuring the distance between the uppermost extents of the opposite sidewalls of the vertical non-planar features.

[0151] As a non-restrictive example, Figure 5A Structure 500 may correspond to a portion of a DRAM device structure partially fabricated prior to metal gap filling deposition, wherein a plurality of vertical non-planar features 504 may include DRAM buried word line trenches, and a plurality of line features 506 may include DRAM word lines.

[0152] Figure 5B Structure 510 is shown, which comprises the previous structure 500 after the nucleation film 512 is directly deposited on the exposed surface of the substrate 502. Figure 5A The nucleation film 512 can be formed by employing a deposition process as described herein (e.g., Figure 3 The first cycle deposition process 220 is used to deposit the nucleation film 512, and the nucleation film 512 can have all the properties (material, thickness, crystallinity, etc.) as previously described herein. Figure 5B As shown, the nucleation membrane 512 may comprise a physically continuous membrane, but it should be noted that in alternative embodiments, the nucleation membrane 512 may comprise a physically discontinuous membrane (not shown).

[0153] As a non-restrictive example, Figure 5B The exemplary structure 510 may correspond to a portion of a DRAM device structure fabricated after the nucleation film has been deposited directly on the DRAM buried word line trench and DRAM word line.

[0154] Figure 5C Structure 514 is shown, which comprises the previous structure 510 after the polycrystalline molybdenum film 516 is directly deposited on the nucleation film 512. Figure 5B The polycrystalline silicon molybdenum film 516 can be deposited using a deposition process as described herein (e.g., Figure 4 The second cycle deposition process 230 is used to deposit the polycrystalline silicon molybdenum film 516, which can have all the properties (resistivity, thickness, crystallinity, etc.) as previously described herein. Figure 5C As shown, the polycrystalline molybdenum film 516 fills the entire non-planar feature 504, for example, from the base of the vertical trench to at least the uppermost part of the vertical trench (or the opening). Furthermore, as... Figure 5C As shown, a polycrystalline molybdenum film 516, placed within and filling the plurality of non-planar features 504, is deposited without forming seams.

[0155] also, Figure 5C This demonstrates that after the deposition of the polycrystalline molybdenum film 516, multiple line features 506 disposed between adjacent filled nonplanar structures 504 have reduced line bending (or deformation), or even no line bending (i.e., compared to...). Figure 1B (Pre-existing technology structure 110). After the metal gap filling process, the reduction or elimination of line curvature in the plurality of line features 506 can be evident from the uniformity of the width of each feature in the vertical non-planar features 504. As a non-limiting example, the plurality of vertical non-planar features 504 of the metal filling may include a width (z), wherein the width (z) of each feature in the array of vertical non-planar features of the metal filling can be determined by measuring the distance across the uppermost extent of the vertical non-planar features of the metal filling.

[0156] In some embodiments, the reduction or elimination of line bend caused by the deposition process and materials of this disclosure can be quantified by determining the line bend percentage.

[0157] As used herein, the term "line bend percentage" can refer to the degree of line bend caused by the deposition of a gap-filling film on a substrate comprising a regular array of nonplanar features. The line bend percentage can be calculated using the following equation (I):

[0158]

[0159] The offset is calculated by the following equation (II):

[0160]

[0161] Or in other words, the offset value is equal to the absolute value of the average width of the non-planar feature after gap-filling film deposition. Figure 5C The average value of (z) minus the average width of the non-planar features before gap-filling film deposition. Figure 5A The average value of (y). As a non-limiting example, the offset can be statistically determined by measuring the width (y) of multiple non-planar features before gap-filling film deposition and subsequently measuring the width (z) of multiple non-planar features after gap-filling film deposition in the non-planar features.

[0162] Therefore, in some embodiments, after the polycrystalline molybdenum film 516 is formed directly on a plurality of nonplanar features 504 disposed between adjacent line features, the line curvature percentage of the plurality of line features 506 may be less than 20%, or less than 10%, or less than 5%, or less than 2%, or less than 1%.

[0163] As a non-limiting example, the substrate may comprise multiple vertical non-planar features and multiple line features. In such an example, the nucleation film may comprise a molybdenum nitride nucleation film deposited directly on the multiple vertical non-planar features and multiple line features. After depositing the molybdenum nitride nucleation film, a polycrystalline molybdenum film may be deposited directly on the molybdenum nitride nucleation film, thereby filling the multiple vertical non-planar features (e.g., V-shaped vertical trenches, or conical vertical trenches) with the polycrystalline molybdenum film. In such an example, the line curvature percentage of the multiple line features may be less than 20%, or less than 10%, or less than 5%, or less than 2%, or even less than 1%. Furthermore, the polycrystalline molybdenum film may comprise multiple molybdenum crystallites having an average crystallite size of less than 90 Å, or less than 80 Å, or less than 70 Å, or less than 60 Å, or even less than 50 Å. In this non-limiting example, the molybdenum nitride nucleation film may have an average film thickness of approximately 20 Å, and the polycrystalline molybdenum film may have an average film thickness of approximately 100 Å and a surface roughness percentage of less than 5%.

[0164] In some embodiments, by performing a pretreatment process on the exposed surface of the substrate prior to the deposition of the nucleation layer, line bends caused by the deposition of interstitial filling metals (e.g., polycrystalline molybdenum films) can be reduced or even eliminated. In some embodiments, the pretreatment process may involve contacting the exposed surface of the substrate, which includes non-planar features, with the pretreatment process. In some embodiments, the pretreatment gas may contain an aluminum component, such as one or more of the following: trimethylaluminum (TMA), triethylaluminum (TEA), dimethylaluminum hydride (DMAH), tri-tert-butylaluminum (TTBA), aluminum trichloride (AlCl3), or dimethylaluminum isopropoxide (DMAI). In some embodiments, the pretreatment gas may contain a silicon component, such as silane gas. In some embodiments, the silane pretreatment gas may contain one or more of the following: silane (SiH4), diethylsilane (Si2H6), propane (Si3H8), butane (Si4H4H6), etc. 10 ), possessing a general empirical Si x H (2x+2) Higher silanes or even chlorosilanes, such as dichlorosilane (DCS). In another embodiment, the pretreatment gas may contain water vapor (H2O) or ammonia (NH3).

[0165] In some embodiments of this disclosure, the pretreatment process may be performed on one or more of a dielectric surface, a semiconductor surface, or a metal surface. In a particular embodiment, the pretreatment process may be performed on a non-planar substrate containing a dielectric surface.

[0166] In some embodiments, in addition to depositing a nucleation film prior to polycrystalline molybdenum film deposition, a pretreatment process may be employed that involves contacting the non-planar substrate with a pretreatment gas. For example, a polycrystalline molybdenum film formation process may include: contacting the exposed surface of the non-planar substrate with a pretreatment gas, subsequently depositing a nucleation film directly onto the pretreated surface of the non-planar substrate, and then depositing the polycrystalline molybdenum film directly onto the nucleation film. In alternative embodiments, the pretreatment process may be applied to the exposed surface of the non-planar substrate, and the nucleation film deposition step may be omitted. For example, a polycrystalline molybdenum film formation process may include contacting the exposed surface of the non-planar substrate with a pretreatment gas, and subsequently depositing a polycrystalline molybdenum film directly onto the pretreated surface of the non-planar substrate.

[0167] Therefore, in some embodiments of this disclosure, the line bend percentage of multiple line features can be reduced or even eliminated by contacting the exposed surface of a non-planar substrate with a pretreatment gas, with or without depositing an intermediate nucleation film prior to the deposition of a polycrystalline molybdenum film. For example, in such embodiments employing pretreatment of the exposed surface of a non-planar substrate, the line bend percentage of multiple pretreated line features may be less than 20%, or less than 10%, or less than 5%, or less than 2%, or less than 1%.

[0168] As a non-restrictive example, Figure 5C Structure 514 may correspond to a portion of a DRAM device structure partially fabricated after inter-metal gap filling deposition, wherein multiple vertical non-planar features 504 comprise DRAM buried word line trenches filled with a polycrystalline molybdenum film 516. Additionally, line features 506 may comprise DRAM word lines, and in this non-limiting example, the line bending percentage of the multiple DRAM word lines may be less than 20%, or less than 10%, or less than 5%, or less than 2%, or less than 1%.

[0169] Embodiments of this disclosure may also provide structures including a polycrystalline molybdenum film formed according to the methods described herein. For example, embodiments of this disclosure may provide a semiconductor device structure, including a partially fabricated semiconductor device structure, the structure including a polycrystalline molybdenum film formed according to embodiments of this disclosure. The structures provided herein may include: a substrate, a nucleation film directly disposed on the surface of the substrate, and a polycrystalline molybdenum film directly disposed on the nucleation film. The structures of this disclosure may be referred to... Figure 5C The structure is shown in 514.

[0170] In more detail, Figure 5C Structure 514 may include: a substrate surface; a nucleation film directly disposed on the substrate surface, wherein the nucleation film comprises at least one of a metal oxide nucleation film or a metal nitride nucleation film; and a polycrystalline molybdenum film directly disposed on the nucleation film; wherein the polycrystalline molybdenum film comprises a plurality of molybdenum crystallites having an average crystallite size of less than 80 Å.

[0171] More specifically, in some embodiments, structure 514 ( Figure 5C The substrate 502 may comprise at least one of a dielectric material, a metallic material, and a semiconductor material. The substrate 502 may comprise one or more of the previously disclosed substrate materials. Additionally, the surface 518 of the substrate 502 may comprise at least one of a dielectric surface, a metallic surface, or a semiconductor surface. The surface 518 of the substrate 502 may comprise one or more of the previously described substrate materials and surfaces.

[0172] Furthermore, the surface 518 of the substrate 502 may include multiple non-planar features, such as vertical non-planar features and / or horizontal non-planar features. For example, the substrate 502 ( Figure 5C ) includes multiple vertical non-planar features 504 ( Figure 5CSurface 518 (shown as a V-shaped vertical trench). It should be understood that surface 518 as described herein may include one or more or a combination of previously disclosed nonplanar features having relevant dimensions, profiles, aspect ratios, etc. In another embodiment, substrate 502 and associated surface 518 may also include a plurality of line features 506, each of which may be disposed between adjacent nonplanar features 504.

[0173] In some embodiments of this disclosure, structure 514 ( Figure 5C The substrate 502 may also include a nucleation film 512, which may be directly disposed on the surface 518 of the substrate 502. In some embodiments, the nucleation film 512 may include at least one of a metal oxide nucleation film or a metal nitride nucleation film.

[0174] In embodiments where nucleation film 512 comprises a metal oxide nucleation film, the metal oxide nucleation film may comprise at least one of the following: aluminum oxide nucleation film, molybdenum oxide nucleation film, tungsten oxide nucleation film, ruthenium oxide nucleation film, rhenium oxide nucleation film, or iridium oxide nucleation film. The metal oxide nucleation film of this disclosure may comprise a physically continuous nucleation film (such as one formed by...). Figure 5C The nucleation film 512 shown herein may be a physically discontinuous nucleation film (not shown). In embodiments where the metal oxide nucleation film is physically continuous, the metal oxide nucleation film may be physically continuous with an average film thickness of less than 40 Å. Alternatively, the metal oxide nucleation film may have an average film thickness as previously disclosed herein, and in certain embodiments, the metal oxide nucleation film may have an average film thickness of less than 30 Å. In some embodiments, the metal oxide nucleation film may comprise an amorphous metal oxide nucleation film.

[0175] In embodiments where nucleation film 512 comprises a metal nitride nucleation film, the metal nitride nucleation film may comprise a molybdenum nitride nucleation film. The metal nitride nucleation film of this disclosure may comprise a physically continuous nucleation film (e.g., formed by...). Figure 5C The nucleation film 512 shown herein may be a physically discontinuous nucleation film (not shown). For example, a molybdenum nitride nucleation film may be physically continuous with an average film thickness of less than 40 Å. Alternatively, a metal nitride nucleation film may have an average film thickness as previously disclosed herein, and in certain embodiments, a metal nitride nucleation film may have an average film thickness of less than 30 Å. In some embodiments, the metal nitride nucleation film may comprise a metal nitride nucleation film.

[0176] In some embodiments of this disclosure, structure 514 ( Figure 5C It may also include a polycrystalline molybdenum film 516, which can be directly disposed on the surface of the nucleation film 512.

[0177] In some embodiments, a polycrystalline molybdenum film 516 may be disposed within a plurality of non-planar features 504 of a substrate 502, wherein the polycrystalline molybdenum film 516 fills the plurality of non-planar features 504 without any observable seams. For example, the substrate 502 may include a surface 518 comprising a plurality of vertical non-planar features 504 (e.g., Figure 5C (Illustrated as a vertical V-shaped groove). In some embodiments, the polycrystalline molybdenum film 516 disposed within the plurality of non-planar features 504 may be examined for the presence of observable seams using high-magnification microscopy techniques, such as transmission electron microscopy (TEM), scanning electron microscopy (SEM), or scanning tunneling electron microscopy (STEM). If such high-magnification microscopy does not reveal the presence of seams, it should be understood that the polycrystalline molybdenum film 516 disposed within the plurality of non-planar features 504 is seamless, i.e., seamless.

[0178] In another embodiment of this disclosure, the surface 518 of the substrate 502 further includes a plurality of vertical non-planar features 504, and the nucleation film 512 is directly disposed on the plurality of vertical non-planar features 504. Furthermore, a polycrystalline molybdenum film 516 may be directly disposed on the nucleation film 512, wherein the polycrystalline molybdenum film 516 fills the plurality of vertical non-planar features 504, and as previously described, no observable seams are observed, as determined using high-magnification microscopy.

[0179] In some embodiments, the structure 514, particularly the surface 518 of the substrate 502, may further include a plurality of line features 506. For example, each line feature 506 may be disposed between adjacent vertical non-planar features 504, such as... Figure 5C The adjacent V-shaped vertical grooves are shown. In some embodiments, the plurality of line features 506 can be sealed with a nucleation film 512 directly disposed on the plurality of line features 506. Alternatively, a polycrystalline molybdenum film 516 can be directly disposed on the nucleation film 512 sealing the plurality of line features 506. In some embodiments, the plurality of line features 506 of structure 514 may have a line bend percentage of less than 20%, or less than 10%, or less than 5%, or less than 2%, or less than 1%. In a particular embodiment, the plurality of line features 506 of structure 514 may have a line bend percentage of less than 20%. In another embodiment, the plurality of line features 506 of structure 514 may have a line bend percentage of less than 10%. In some embodiments, the plurality of line features 506 of structure 514 may have a line bend percentage between approximately 1% and 20%. In some embodiments, the plurality of line features 506 of structure 514 may be substantially free of line bend, i.e., have a line bend percentage of approximately 0%.

[0180] In some embodiments, the surface roughness of the polycrystalline molybdenum film 516 of structure 514 can be expressed as a roughness percentage of the total average film thickness of the polycrystalline molybdenum film 516. For example, in some embodiments, the surface roughness percentage of the polycrystalline molybdenum film 516 may be less than 10%, or less than 5%, or less than 3%, or less than 1.5%, or even less than 1%. In some embodiments, the surface roughness percentage of the polycrystalline molybdenum film 516 may be between approximately 1% and 10%.

[0181] In some embodiments, the polycrystalline molybdenum film 516 of structure 514 may comprise a plurality of molybdenum crystallites, wherein the average crystallite size may be less than 100 Å, or less than 80 Å, or less than 60 Å, or less than 40 Å, or even less than 20 Å. In some embodiments, the molybdenum crystallites may have an average crystallite size between approximately 20 Å and 100 Å, or between approximately 20 Å and 75 Å, or even between approximately 20 Å and 50 Å.

[0182] As a non-limiting example, the polycrystalline molybdenum film 516 can be directly deposited on the molybdenum nitride nucleation film, and the molybdenum crystallites of the polycrystalline molybdenum film 516 can have an average crystallite size of less than about 60 Å, or less than about 50 Å, or even less than about 40 Å, or between about 20 Å and 60 Å. In a particular example, the nucleation film 512 can comprise a molybdenum nitride nucleation film, and the polycrystalline molybdenum film 516 has an average crystallite size of less than 60 Å and a roughness percentage of less than 10%.

[0183] In some embodiments, the nucleation film 512 and the polycrystalline molybdenum film 516 together form a bilayer directly disposed on the surface 518 of the substrate 502. In some embodiments, the bilayer may have a resistivity of less than 50 μΩ-cm, or less than 30 μΩ-cm, or less than 20 μΩ-cm, or even less than 25 μΩ-cm, or between approximately 25 μΩ-cm and 50 μΩ-cm, wherein the bilayer may comprise a nucleation film having an average film thickness of less than 20 Å and a polycrystalline molybdenum film having an average film thickness of more than 100 Å.

[0184] In some embodiments of this disclosure, structure 514 ( Figure 5C The device may include a device structure, and in some embodiments, it may include a partially manufactured device structure. For example, a partially manufactured device structure may include at least one of a DRAM device structure, a 3D-NAND device structure, a 3D integrated device structure, or an integrated logic device structure.

[0185] In embodiments where structure 514 includes a partially fabricated DRAM device structure, the non-planar substrate 502 may include a plurality of non-planar features 504 comprising a plurality of DRAM buried word line trenches, and the plurality of line features 506 may include a plurality of DRAM word lines. In such embodiments, the nucleation film 512 may be directly disposed on the plurality of DRAM buried word line trenches and directly disposed on the plurality of DRAM word lines.

[0186] In embodiments where structure 514 includes a partially fabricated DRAM device structure, a polycrystalline molybdenum film 516 may be disposed within and fill a plurality of DRAM buried word line trenches. In such embodiments, the polycrystalline molybdenum film 516 disposed within and filling the plurality of DRAM buried word line trenches may contain unobservable seams, i.e., the filled DRAM buried word line trenches are seamless, as determined by high-magnification microscopy techniques as previously described herein.

[0187] Additionally, in embodiments where structure 514 includes a partially fabricated DRAM device structure, the line bending percentage of the plurality of DRAM word lines may be less than 20%, or less than 10%, or less than 5%, or less than 2%, or less than 1%, or even between approximately 1% and 20%. In some embodiments, the plurality of DRAM word lines may be substantially free of line bending, i.e., have a line bending percentage of approximately 0%.

[0188] As a non-limiting example, structure 514 may comprise a partially fabricated DRAM device structure comprising a polycrystalline molybdenum film 516 directly disposed on a molybdenum nitride nucleation film 512. In such a partially fabricated DRAM device structure, the plurality of molybdenum crystallites of the polycrystalline molybdenum film 516 may have an average crystallite size of less than about 60 Å, or less than about 50 Å, or even less than about 40 Å, or between about 40 Å and 60 Å. As a specific example of a partially fabricated DRAM device structure, the nucleation film 512 may comprise a molybdenum nitride nucleation film and the polycrystalline molybdenum film 516 may have an average crystallite size of less than 60 Å and a roughness percentage of less than 10% for the polycrystalline molybdenum film 516.

[0189] The exemplary embodiments described above do not limit the scope of the invention, as these embodiments are merely examples of embodiments of the invention, which is defined by the appended claims and their legal equivalents. Any equivalent embodiments are intended to be included within the scope of the invention. In fact, various modifications to this disclosure, such as alternative combinations of the described elements, will be apparent to those skilled in the art from the specification, in addition to those shown and described herein. Such modifications and embodiments are also intended to fall within the scope of the appended claims.

Claims

1. A method for forming a polycrystalline molybdenum film on a substrate surface, the method comprising: The substrate is provided into the reaction chamber; The nucleation film is deposited directly on the exposed surface of the substrate, wherein the nucleation film comprises one of a metal oxide nucleation film or a metal nitride nucleation film; as well as Polycrystalline molybdenum film is directly deposited on the nucleation film; The polycrystalline molybdenum film comprises multiple molybdenum crystallites with an average crystallite size of less than 80 angstroms. Prior to depositing the nucleation film, a pretreatment process is performed on the exposed surface of the substrate. This pretreatment process includes contacting the substrate with a pretreatment gas, which includes an aluminum component, a silicon component, water vapor, ammonia, or a combination thereof. The exposed surface of the substrate includes multiple vertical non-planar features and multiple line features, wherein the line curvature percentage of the multiple line features is less than 20% after the deposition of the nucleation film and the polycrystalline molybdenum film. The line curvature percentage is quantified by the degree of line curvature caused by the deposition of the polycrystalline molybdenum film on the substrate. The percentage of line curvature is calculated by the following equation: Line curvature percentage (%) = (offset / spacing) x 100 Wherein, the offset is equal to the absolute value of the average width of the non-planar feature after deposition minus the average width of the non-planar feature before deposition. The spacing is defined as the distance between the middle vertical axis of a line feature and the middle vertical axis of an adjacent line feature.

2. The method of claim 1, wherein depositing the nucleation film comprises performing one or more first unit deposition cycles of a first cycle deposition process, wherein the first unit deposition cycle comprises contacting the substrate sequentially with a metal precursor and with one of an oxygen precursor or a nitrogen precursor.

3. The method of claim 1, wherein depositing the polycrystalline molybdenum metal film comprises performing one or more second unit deposition cycles of a second cyclic deposition process, wherein the second unit deposition cycle comprises contacting the substrate sequentially with a molybdenum halide precursor and a reducing agent.

4. The method according to claim 3, wherein the molybdenum halide precursor comprises at least one of the following: molybdenum trichloride (V) (MoOCl3), molybdenum tetrachloride (VI) (MoOCl4), or molybdenum dichloride (IV) (MoO2Cl2).

5. The method of claim 1, wherein the metal nitride nucleation film comprises a molybdenum nitride nucleation film, and the molybdenum nitride nucleation film has an average film thickness of less than 30 Å.

6. The method of claim 1, wherein the polycrystalline molybdenum film is deposited within a plurality of nonplanar features, wherein the polycrystalline molybdenum film fills the plurality of nonplanar features without forming seams.

7. The method of claim 1, wherein the bilayer of the polycrystalline molybdenum film and the nucleation film has a resistivity of less than 25 μΩ-cm with an average nucleation film thickness of less than 20 Å and an average polycrystalline molybdenum film thickness of less than 100 Å.

8. The method of claim 1, wherein the nucleating membrane is a physically continuous membrane with an average membrane thickness of less than 50 Å.

9. The method of claim 1, wherein the nucleation film is deposited directly on the exposed surface, and the polycrystalline molybdenum film is deposited directly on the nucleation film, wherein the polycrystalline molybdenum film fills the plurality of vertical non-planar features without forming seams.

10. The method of claim 9, wherein the exposed surface comprises a dielectric surface.

11. The method of claim 1, wherein the substrate further comprises a plurality of line features, wherein the line bending percentage of the plurality of line features is less than 10% after the nucleation film and the polycrystalline molybdenum film are deposited.

12. The method of claim 1, wherein the polycrystalline molybdenum film has an average crystallite size of less than 60 Å.

13. The method of claim 1, wherein the polycrystalline molybdenum film has a roughness percentage of less than 10%.

14. The method of claim 1, wherein the polycrystalline molybdenum film has a roughness percentage of less than 5%.

15. The method of claim 1, wherein the nucleating film comprises a molybdenum nitride nucleating film and the polycrystalline molybdenum film has a roughness percentage of less than 10%.

16. The method of claim 1, wherein the exposed surface of the substrate comprises a dielectric surface.

17. A structure comprising a polycrystalline molybdenum film formed according to the method of claim 1.

18. A reaction system configured to perform the method according to claim 1.

19. A structure comprising: The surface of the substrate; A nucleation film directly disposed on the surface of the substrate, wherein the nucleation film comprises one of a metal oxide nucleation film or a metal nitride nucleation film; and A polycrystalline molybdenum film directly disposed on the nucleation film; The polycrystalline molybdenum film comprises multiple molybdenum crystallites with an average crystallite size of less than 80 Å. The surface of the substrate includes a plurality of vertical non-planar features and a plurality of line features, wherein the line curvature percentage of the plurality of line features is less than 20%. in, The line curvature percentage is quantified by the degree of line curvature caused by the deposition of the polycrystalline molybdenum film on the substrate. The percentage of line curvature is calculated by the following equation: Line curvature percentage (%) = (offset / spacing) x 100 Wherein, the offset is equal to the absolute value of the average width of the non-planar feature after deposition minus the average width of the non-planar feature before deposition. The spacing is defined as the distance between the middle vertical axis of a line feature and the middle vertical axis of an adjacent line feature.

20. The method of claim 19, wherein the metal nitride nucleation film comprises a molybdenum nitride nucleation film, and the molybdenum nitride nucleation film has an average film thickness of less than 30 Å.

21. The structure of claim 19, wherein the polycrystalline molybdenum film is disposed within a plurality of non-planar features, wherein the polycrystalline molybdenum film fills the plurality of non-planar features without observable seams.

22. The structure of claim 19, wherein the bilayer comprising the polycrystalline molybdenum film and the nucleation film has a resistivity of less than 25 μΩ-cm with an average nucleation film thickness of less than 20 Å and an average polycrystalline molybdenum film thickness of less than 100 Å.

23. The structure of claim 19, wherein the nucleating membrane is a physically continuous membrane with an average membrane thickness of less than 40 Å.

24. The structure according to claim 19, wherein the nucleating film is directly disposed on the plurality of vertical non-planar features, and the polycrystalline molybdenum film is directly disposed on the nucleating film, wherein the polycrystalline molybdenum film fills the plurality of vertical non-planar features without observable seams.

25. The structure of claim 19, wherein the surface of the substrate comprises a dielectric surface.

26. The structure of claim 24, wherein the substrate further comprises a plurality of line features, wherein the line bending percentage of the plurality of line features is less than 10%.

27. The structure according to claim 19, wherein the polycrystalline molybdenum film has an average crystallite size of less than 60 Å.

28. The structure according to claim 19, wherein the polycrystalline molybdenum film has a roughness percentage of less than 10%.

29. The structure of claim 19, wherein the substrate comprises a partially fabricated device structure, the partially fabricated device structure comprising at least one of the following: a DRAM device structure, a 3D-NAND device structure, a 3D integrated device structure, or an integrated logic device structure.

30. The structure of claim 29, wherein the substrate comprises a partially fabricated DRAM device structure, wherein the substrate comprises a plurality of DRAM buried word line trenches and a plurality of DRAM word lines.

31. The structure according to claim 30, wherein the nucleation film is directly disposed on the plurality of DRAM embedded word line trenches and directly disposed on the plurality of DRAM word lines.

32. The structure according to claim 31, wherein the polycrystalline molybdenum film is disposed within and fills the plurality of DRAM embedded word line trenches.

33. The structure of claim 32, wherein the line bending percentage of the plurality of DRAM word lines is less than 20%.

34. The structure of claim 33, wherein the nucleating film comprises a molybdenum nitride nucleating film and the polycrystalline molybdenum film has a roughness percentage of 1.5%.

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