High purity alkynes for selective deposition

Abstract

The disclosed and claimed invention relates to high purity alkynes that are substantially free of residual alkyl halides, water and / or carboxylic acids, and their use (e.g., in formulations) for enhanced passivation of metal substrates.

Description

[Technical field]

[0001] The disclosed and claimed invention relates to high purity alkynes useful for selectively depositing dielectric films on non-metallic substrates. More particularly, the disclosed and claimed invention relates to high purity alkynes and their use for enhanced passivation of metallic substrates. [Background technology]

[0002] Transition metal-containing films are used in semiconductor and electronic applications. Chemical vapor deposition (CVD) and atomic layer deposition (ALD) are the primary deposition techniques used to produce thin films for semiconductor devices. These methods allow for the achievement of conformal films (metal, metal oxide, metal nitride, metal silicide, etc.) through chemical reactions of metal-containing compounds (precursors). These chemical reactions occur on surfaces, which may include metal, metal oxide, metal nitride, metal silicide, and other surfaces. In CVD and ALD, precursor molecules play a critical role in achieving high quality films with high conformality and low impurity content. The substrate temperature in CVD and ALD processes is a major consideration in the selection of precursor molecules. Relatively high substrate temperatures ranging from 150 to 500° C. promote higher deposition rates. Preferred precursor molecules should be stable in this temperature range. Preferred precursors can be delivered to the reaction vessel in liquid phase. Liquid phase delivery of precursors generally provides more uniform delivery of precursors to the reaction vessel compared to solid phase precursors.

[0003] CVD and ALD processes are increasingly used because they have the advantages of enhanced composition control, high film uniformity, and effective control of doping. In addition, CVD and ALD processes provide excellent conformal step coverage on the highly non-planar topography associated with modern microelectronic devices. CVD and ALD are particularly attractive for producing conformal metal-containing films using these metal-containing precursors on substrates such as silicon, silicon oxide, metal nitride, metal oxide, and other metal-containing layers. In these techniques, the vapor of a volatile metal complex is introduced into a process chamber where it contacts the surface of a silicon wafer, and then a chemical reaction occurs to deposit a thin film of a pure metal or metal compound.

[0004] CVD is a chemical process in which precursors are used to form thin films on a substrate surface. In a typical CVD process, precursors are flowed onto the surface of a substrate (e.g., a wafer) in a low-pressure or ambient pressure reaction chamber. The precursors react and / or decompose on the substrate surface to form a thin film of deposited material. Plasma can be used to assist the reaction of the precursors or to improve the properties of the material. Non-volatile by-products are removed by flowing gas through the reaction chamber. The deposited film thickness can be difficult to control, as it depends on the coordination of many parameters such as temperature, pressure, gas volume flow and uniformity, chemical depletion effects, and time. Thus, CVD occurs when precursors react on the wafer surface, either thermally or with reagents added simultaneously in the process chamber, and film growth occurs in steady-state deposition. CVD can be applied in a continuous or pulsed mode to achieve the desired film thickness.

[0005] ALD is a chemical method for the deposition of thin films. It is a self-limiting, continuous and unique film growth technique based on surface reactions that can provide precise thickness control and can deposit conformal thin films of materials provided by precursors on surface substrates of various compositions. In ALD, precursors are separated during reaction. A first precursor is flowed onto the substrate surface to produce a monolayer on the substrate surface. Excess unreacted precursor is evacuated from the reaction chamber. A second precursor or co-reactant is then flowed onto the substrate surface and reacts with the first precursor to form a second monolayer of film on the first formed monolayer of film on the substrate surface. Plasma can be used to assist the reaction of precursors or co-reactants or to improve material quality. This cycle is repeated until a film of the desired thickness is formed. ALD provides deposition of ultra-thin, yet continuous, metal-containing films with precise control of film thickness, excellent film thickness uniformity and exceptionally conformal film growth for flat coating of deeply etched and highly intricate structures such as interconnect vias and trenches. Therefore, ALD is typically preferred for depositing thin films on features with high aspect ratios.

[0006] Thin films, particularly metal-containing thin films, have a variety of important applications in nanotechnology and in the manufacture of semiconductor devices. Examples of such applications include capacitor electrodes, gate electrodes, adhesive diffusion barriers, and integrated circuits. However, the size of microelectronic components, such as semiconductor devices, is constantly shrinking, presenting several technical challenges and creating a demand for improved thin film technologies. In particular, microelectronic components may contain features on or within a substrate that require filling, for example, to form conductive paths or to form interconnects. Filling such features, especially in smaller and smaller microelectronic components, can be difficult as these features can become increasingly thinner or narrower. As a result, complete filling of a feature, for example by ALD, would require infinitely long cycle times as the feature thickness approaches zero. Furthermore, when the feature thickness becomes thinner than the molecular size of the precursor, the feature cannot be completely filled. As a result, ALD may leave a hollow seam in the center of the feature. The presence of such a hollow seam in the feature is undesirable as it may lead to device failure. Therefore, there is great interest in developing thin film deposition methods, particularly ALD methods, that can selectively grow films on more than one substrate and achieve improved filling of features on or in a substrate, such as depositing metal-containing films such that the features are substantially filled without the introduction of voids.

[0007] As can be seen from the above, in conventional semiconductor device manufacturing, patterning is a "top-down" process based mainly on photolithography and etching, which is the main bottleneck for device size reduction. In contrast, area-selective deposition (e.g., CVD and ALD) is an alternative "bottom-up" patterning method for advanced semiconductor manufacturing, in which a metal layer (e.g., Ru) is grown on the bottom metal surface (e.g., Ru and TiN) adjacent to a passivated dielectric substrate, rather than on the dielectric (e.g., SiO2) sidewalls. See, e.g., FIG. 1. It is also desirable that these processes be oxygen-free and / or have relatively low resistance.

[0008] In other applications, it is desirable to deposit dielectric films only on other dielectric films and not on metal surfaces. See, for example, FIG. 2. One potential application of such a process is self-aligned fabrication. The most common strategy to achieve selective growth is based on selective passivation of the non-growth surface. Small volatile molecules are highly desirable for passivation because they can be delivered via the gas phase. Selective passivation of non-metal surfaces that have a high concentration of hydroxyl groups is becoming widely used, which can be achieved by a variety of silylating agents, e.g., R x SiCl y , R x Si(NR2) y On the other hand, selective passivation of metal surfaces is much more difficult, and the selectivity of this method can be easily lost due to desorption of the passivating agent, incomplete passivation due to residual impurities on the surface of the metal film, etc. To passivate non-growth surfaces, single-component reagents are typically used. However, single-component reagents may not provide complete surface coverage of the metal surface due to the presence of various sites on the metal surface, such as "bare" metal, halogen-terminated metal, oxygen- or hydroxyl-terminated metal, etc.

[0009] Alkynes have been used to passivate metal surfaces to deposit films on growing dielectric surfaces while substantially inhibiting film growth on metallic non-growth surfaces. However, previously disclosed alkynes provide insufficient passivation on metal sites due to contamination with traces of moisture, halides, and carboxylic acids. Typically, substituted alkynes are prepared by reacting metal acetylides with alkyl halides, followed by aqueous workup. See, for example, Morrison and Boyd, Organic Chemistry, 558-560 (1983). As a result, the alkynes are contaminated with traces of residual alkyl halides, moisture, and carboxylic acids.

[0010] For example, US Patent Application Publication No. 2020 / 0347493 discloses a method for selective deposition of a dielectric film on a non-metallic surface. The disclosed method requires passivation or blocking of the metal surface prior to depositing the dielectric film. In some embodiments, the method includes treatment of the metal surface with an unsaturated hydrocarbon having at least one carbon-carbon triple bond (e.g., 3-hexyne, 4-octyne, 5-decyne, 6-dodecyne, and 7-tetradecyne). According to the application, the unsaturated hydrocarbon is believed to inhibit nucleation and growth on the metal substrate. Although the application provides a method for blocking a metal surface, it does not teach or suggest a process for passivating residual metal oxide sites present on the metal surface.

[0011] Reproducible selective passivation of metal surfaces requires careful design of precursors and deposition processes. In fact, it is highly desirable to reduce and / or eliminate passivation of dielectric surfaces while enhancing passivation of metal surfaces. The disclosed and claimed invention provides compositions and methods for enhanced passivation and / or blocking of metal surfaces and enhanced selective deposition of non-metallic surfaces relative to metal surfaces.

[0012] To achieve selective surface growth during semiconductor manufacturing (i.e., simultaneous or substantially simultaneous growth and non-growth on different surfaces), it is typically desirable to utilize (i) metal surfaces that are believed to be free or substantially free of hydroxyl groups, and (ii) non-metal surfaces that contain a high concentration of hydroxyl groups. Examples of suitable metal surfaces include, but are not limited to, copper, cobalt, tungsten, molybdenum, nickel, ruthenium, and the like. Examples of non-metal surfaces include, but are not limited to, silicon oxide, low K carbon doped silicon oxide, silicon nitride, silicon carbonitride, and metal oxides such as aluminum oxide, tantalum oxide, hafnium oxide, zirconium oxide, and the like. Examples of films deposited on non-metal surfaces include, but are not limited to, silicon oxide, aluminum oxide, tantalum oxide, titanium oxide, hafnium oxide, zirconium oxide, tantalum nitride, titanium nitride, and the like. These films are deposited on the non-metal surfaces by chemical vapor deposition and atomic layer deposition processes as described above. Precursors useful for depositing the films include, but are not limited to, trimethylaluminum, tetrakis(dimethylamido)titanium, pentakis(dimethylamido)tantalum, tert-butylimido-tris(dimethylamido)tantalum, tert-butylimido-tris(dimethylamido)niobium, etc. Co-reactants include, but are not limited to, water, ammonia, etc.

[0013] To achieve selective deposition, the metal surface must be passivated and must be free or substantially free of chemical groups reactive to the precursors and co-reactants, e.g., ammonia, used in the next process step for film deposition. On the other hand, the reactants used to passivate the metal surface should not passivate the desired growth on the non-metallic surfaces. The disclosed and claimed formulations are uniquely designed to balance these needs in a selective deposition process. [Prior art documents] [Patent documents]

[0014] [Patent Document 1] US Patent Application Publication No. 2020 / 0347493 [Non-patent literature]

[0015] [Non-Patent Document 1] Morrison and Boyd,Organic Chemistry,558-560(1983) Summary of the Invention

[0016] The disclosed and claimed invention relates to high purity alkynes that are substantially free of residual alkyl halides, water and / or carboxylic acids, and their use (e.g., in formulations) for enhanced passivation of metal substrates.

[0017] In another aspect, the disclosed and claimed invention includes the use of the above formulation in a selective CVD deposition process.

[0018] In another aspect, the disclosed and claimed invention includes the use of the above formulation in a selective ALD deposition process.

[0019] The accompanying drawings are intended to provide a further understanding of the disclosed invention, and are incorporated in and constitute a part of this specification, illustrate embodiments of the disclosed invention, and together with the detailed description of the invention, serve to explain the principles of the disclosed invention. [Brief description of the drawings]

[0020] [Figure 1] FIG. 1 shows an exemplary target for a selective deposition process in which a metal film is selectively deposited onto a conductive film, while a dielectric film is passivated. [Diagram 2] FIG. 2 shows an exemplary target for a selective deposition process in which a dielectric film is selectively deposited on a dielectric film while a metal surface is passivated. [Diagram 3]FIG. 3 shows the dependence of the Ta XPS signal on the passivation process conditions, such as the purity of the passivation agent (SAM) and the exposure time (SAM grafting time). DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] All references cited herein, including but not limited to publications, patent applications, and patents, are herein incorporated by reference to the same extent as if each individual reference was individually and specifically indicated to be incorporated by reference and was set forth in its entirety.

[0022] The use of the singular and similar referents in the context of the description of the disclosed and claimed invention (especially in the context of the subclaims) should be construed to include both the singular and the plural, unless otherwise indicated or clearly contradicted by the context. The terms "comprise," "having," "including," and "containing" should be construed as non-exclusive (i.e., meaning "including, but not limited to"), unless otherwise indicated. The recitation of numerical ranges, unless otherwise indicated herein, is merely intended to serve as a shorthand method of referring to each and every separate value falling within the range, and each separate value shall be set forth in the specification as if each were set forth herein individually. All methods described herein may be performed in any suitable order, unless otherwise indicated or otherwise clearly contradicted by the context. The use of any and all examples or exemplary language (e.g., "etc.") described herein, unless otherwise indicated, is merely intended to facilitate easier understanding of the disclosed and claimed invention, and does not limit the scope of the disclosed and claimed invention. Nothing in the specification should be construed as representing any non-claimed subject matter as essential to the practice of the disclosed and claimed invention. Use of the term "comprising" in the specification and claims encompasses the narrower scope of "consisting essentially of" and "consisting of."

[0023] Aspects of the disclosed and claimed invention are described herein, including the best mode known to the inventors for carrying out the disclosed and claimed invention. Variations of these aspects may become apparent to those of skill in the art upon reading the foregoing description. The inventors anticipate that such variations may be employed by those of skill in the art, and the inventors also intend that the disclosed and claimed invention may be practiced otherwise than as specifically described herein. Accordingly, the disclosed and claimed invention is intended to include all modifications and equivalents / methods of the claimed invention to the extent permitted by applicable law. Moreover, any combination of the above-described features in all possible variations thereof is included in the disclosed and claimed invention unless otherwise indicated or clearly contradicted by context.

[0024] The reference to "silicon" is understood to also include polysilicon when deposited as a material on a microelectronic device.

[0025] For ease of reference, the term "microelectronic device" or "semiconductor device" refers to semiconductor wafers having integrated circuits, memories, or other mounted electronic structures manufactured for use in microelectronic, integrated circuit, or computer chip applications, as well as other products such as flat panel displays, phase change memory devices, solar panels, solar cell substrates, photovoltaic devices, and microelectromechanical systems (MEMS). Solar cell substrates include, but are not limited to, silicon, amorphous silicon, polycrystalline silicon, single crystalline silicon, CdTe, copper indium selenide, copper indium sulfide, and gallium-on-gallium arsenide. Solar cell substrates may be doped or undoped. The terms "microelectronic device" or "semiconductor device" are not meant to be limiting in any way and include any substrate that will ultimately become a microelectronic device or microelectronic assembly.

[0026] As defined herein, the term "barrier material" corresponds to any material used in the art to encapsulate metal lines, e.g., copper interconnects, to minimize diffusion of said metal, e.g., copper, into dielectric materials. Preferred barrier layer materials include tantalum, titanium, ruthenium, hafnium, and other refractory metals, and their nitrides and silicides.

[0027] "Substantially free" is defined herein as less than 0.001% by weight. "Substantially free" also includes 0.000% by weight. The term "free" means 0.000% by weight. As used herein, "about" or "approximately" is intended to mean within ±5% of the stated value.

[0028] The term "alkylene", unless otherwise specified, means a linear saturated divalent hydrocarbon radical having from one to six carbon atoms or a branched saturated divalent hydrocarbon radical having three to six carbon atoms (e.g., methylene, ethylene, propylene, 1-methylpropylene, 2-methylpropylene, butylene, pentylene, and the like).

[0029] "Heteroalkylene" refers to an -(alkylene)- group as defined above in which one, two or three carbons in the alkylene chain are replaced by -O-, N(H, alkyl, or substituted alkyl), S, SO, SO2, or CO. In some preferred embodiments, said carbons are replaced by O or N.

[0030] In all such compositions, when specific components of the composition are described in terms of weight percentage (or "wt %") ranges including a zero lower limit, it is understood that such components may or may not be present in various specific embodiments of the composition, and that when such components are present, they may be present in concentrations as low as 0.001 weight percent, based on the total weight of the composition in which such components are used. All percentages of components are weight percent and are based on the total weight of the composition (i.e., 100%). References to "one or more" or "at least one" include "two or more," "three or more," etc.

[0031] If applicable, and unless otherwise indicated, all weight percentages are "net," meaning that they do not include the aqueous solution they are in when added to the composition. For example, "net" refers to the weight percent amount of undiluted acid or other material (i.e., if you have 100 g of 85% phosphoric acid, it is made up of 85 g of that acid and 15 g of diluent).

[0032] Furthermore, when compositions described herein are stated in terms of weight percent, it is understood that in any case the weight percents of all components, including non-essential components such as impurities, do not add up to more than 100 weight percent. In a composition "consisting essentially" of the described components, such components may add up to 100 weight percent of the composition or may add up to less than 100 weight percent. When the components add up to less than 100 weight percent, such compositions may contain some small amount of non-essential contaminants or impurities. For example, in one such embodiment, the formulation may contain 2 weight percent or less of impurities. In another embodiment, the formulation may contain 1 weight percent or less of impurities. In yet another embodiment, the formulation may contain 0.05 weight percent or less of impurities. In other such embodiments, the components may comprise at least 90 weight percent, more preferably at least 95 weight percent, more preferably at least 99 weight percent, more preferably at least 99.5 weight percent, and most preferably at least 99.9 weight percent, and may include other components that do not substantially affect performance. Otherwise, in the absence of significant non-essential impurity components, the composition of all essential constituents will be understood to add up to essentially 100% by weight.

[0033] The headings used herein are not intended to be limiting; they are included solely for organizational purposes.

[0034] As previously described, the disclosed and claimed invention relates to high purity alkynes substantially free of residual alkyl halides, water, carboxylic acids, and their use (e.g., in formulations) for enhanced passivation of metal substrates. In particular, it has been found that the high purity alkynes can easily passivate metal surfaces that are free or substantially free of hydroxyl groups by strongly adsorbing on the "bare" metal surfaces. For example, it has been found that the alkynes strongly adsorb on "bare" copper surfaces with adsorption energies of -40 to 45 kcal / mol. On the other hand, this behavior is at best inconsistent on partially hydroxylated metal surfaces; for example, it has been found that unsubstituted alkynes do not adsorb well on hydroxylated metal surfaces such as copper(I) oxide. Thus, while on the one hand the alkynes can be utilized on "bare" metal surfaces, most metal surfaces contain residual oxides that require further processing to render them free reactive. It is therefore important to eliminate impurities that may form hydroxylated metal surfaces. It has also been found that dissociative adsorption of alkyl halides on metal surfaces is thermodynamically highly favored. Residual halides on metal surfaces react with precursors and reactants used for selective deposition, suppressing process selectivity. Therefore, it is important to eliminate halogen-containing impurities that can form halide-containing species on metallic substrates.

[0035] Disclosed and Claimed Formulations Given the above, in one aspect, the disclosed and claimed invention relates to high-purity alkynes that are substantially free of residual alkyl halides, water, and / or carboxylic acids. Preferred high-purity alkynes include those exemplified in Tables 1 to 3. However, it should be understood that the high-purity alkynes are not limited to those exemplified in Tables 1 to 3.

[0036] [Table 1]

[0037] [Table 2]

[0038] [Table 3]

[0039] One preferred high purity alkyne is 5-decyne (3E).

[0040] Another preferred high purity alkyne is 3-hexyne (1I).

[0041] In one embodiment, the high purity alkynes are substantially free of water. In one aspect of this embodiment, the high purity alkynes have a residual water concentration of less than about 500 ppm. In one aspect of this embodiment, the high purity alkynes have a residual water concentration of less than about 100 ppm. In one aspect of this embodiment, the high purity alkynes have a residual water concentration of less than about 50 ppm. In one aspect of this embodiment, the high purity alkynes have a residual water concentration of less than about 25 ppm. In one aspect of this embodiment, the high purity alkynes have a residual water concentration of less than about 10 ppm. In one aspect of this embodiment, the high purity alkynes have no detectable water. In one aspect of this embodiment, the high purity alkynes are free of water.

[0042] In one embodiment, the high purity alkynes are substantially free of carboxylic acids. In one aspect of this embodiment, the high purity alkynes have a residual concentration of carboxylic acids of less than about 1000 ppm. In one aspect of this embodiment, the high purity alkynes have a residual concentration of carboxylic acids of less than about 500 ppm. In one aspect of this embodiment, the high purity alkynes have a residual concentration of carboxylic acids of less than about 100 ppm. In one aspect of this embodiment, the high purity alkynes have no detectable carboxylic acids. In one aspect of this embodiment, the high purity alkynes are free of carboxylic acids.

[0043] In one embodiment, the high purity alkynes are substantially free of impurities that may react with metal surfaces during a passivation process, hi one embodiment, the high purity alkynes are substantially free of impurities that may react with precursors during a deposition process.

[0044] In one embodiment, the high purity alkynes are substantially free of impurities that passivate and inhibit growth on non-metallic surfaces.

[0045] In one embodiment, the high purity alkynes are substantially free of halogen-containing impurities. In one aspect of this embodiment, the halogen-containing impurities are one or more of fluorine-containing hydrocarbons, chlorine-containing hydrocarbons, bromine-containing hydrocarbons, and iodine-containing hydrocarbons. In one aspect of this embodiment, the high purity alkynes have a residual concentration of halogen-containing impurities less than about 1000 ppm. In one aspect of this embodiment, the high purity alkynes have a residual concentration of halogen-containing impurities less than about 500 ppm. In one aspect of this embodiment, the high purity alkynes have a residual concentration of halogen-containing impurities less than about 100 ppm. In one aspect of this embodiment, the high purity alkynes have a residual concentration of halogen-containing impurities less than about 50 ppm. In one aspect of this embodiment, the high purity alkynes have a residual concentration of halogen-containing impurities less than about 10 ppm. In one aspect of this embodiment, the high purity alkynes are free of halogen-containing impurities. In the following aspects, residual concentrations of halogen-containing impurities are detected by one or more of the following: gas chromatography (GC) and its related hybrid techniques (such as, but not limited to, GC-FID, GC-ECD, GC-MS); liquid chromatography (which is defined to include LC, HPLC or UPLC variations) and its related hybrid techniques (such as, but not limited to, LC-DAD and LC-MS); ion chromatography (IC) and its related forms; spectroscopic techniques, such as, but not limited to, infrared (IR), ultraviolet / visible (UV / Vis), near infrared, infrared (NIR), infrared (IR), infrared (UV / Vis ... (NIR), Raman and nuclear magnetic resonance (NMR) spectroscopy; inductively coupled plasma spectroscopy or spectrometry (ICP) and their related hybrid techniques (such as, but not limited to, ICP-MS, ICP-OES, GC-ICP-MS, and GC-ICP-OES); elemental analysis, such as X-ray fluorescence spectroscopy (XRF) and related forms thereof (e.g., WD-XRF) or atomic absorption spectroscopy (AA) and forms thereof; and finally wet chemical techniques (such as, but not limited to, titration (e.g., halogen titration with silver nitrate) and electrochemical detection methods (e.g., cyclic voltammetry, ion selective electrodes, etc.).In one embodiment of the above aspect, the residual concentration of halogen-containing impurities is detected by one or more of GC-MS, GC-ICP-MS, GC-ICP-OES, GC-FID, GC-ECD, HPLC, and UV / Vis.

[0046] In one embodiment, the high purity alkynes are purified by adsorption on alumina. In one aspect of this embodiment, the alkynes are passed through an adsorption bed packed with acidic alumina. In another aspect of this embodiment, the alkynes are passed through an adsorption bed packed with neutral alumina. In another aspect of this embodiment, the alkynes are passed through an adsorption bed packed with basic alumina. In another aspect of this embodiment, the alkynes are passed through an adsorption bed containing a combination of acidic, basic and neutral aluminas.

[0047] In one embodiment, the high purity alkynes are purified by exposure to molecular sieves. In one embodiment, the high purity alkynes are purified by exposure to silica gel. In one embodiment, the high purity alkynes are purified by exposure to one or more adsorbent materials.

[0048] In one embodiment, the high purity alkynes are purified by treatment with one or more Group (I) metals, followed by a distillation process. In one aspect of this embodiment, the alkynes are treated with metallic sodium. In another aspect of this embodiment, the metal and alkynes are separated by filtration, and the alkynes are distilled to remove non-volatile products of the reaction of the impurities with the metal.

[0049] In one embodiment, the high purity alkynes are purified by treatment with one or more Group (II) metals, followed by a distillation process. In one aspect of this embodiment, the alkynes are treated with metallic magnesium. In another aspect of this embodiment, the metal and alkynes are separated by filtration, and the alkynes are distilled to remove non-volatile products of the reaction of the impurities with the metal.

[0050] In one embodiment, the high purity alkynes are purified by exposure to activated charcoal. In one aspect of this embodiment, the alkynes are separated by filtration and distilled to remove non-volatile products after treatment with activated charcoal.

[0051] In another aspect of this embodiment, the (i) one or more alkynes are high purity alkynes.

[0052] How to use The disclosed and claimed invention further includes the use of one or more of the disclosed and claimed high purity alkynes in chemical vapor deposition processes known to those skilled in the art. As used herein, the term "chemical vapor deposition process" refers to any process in which a substrate is exposed to one or more volatile precursors that react and / or decompose on the substrate surface to produce a desired deposit.

[0053] In one embodiment, the method includes the use of one or more of the disclosed and claimed high purity alkynes to passivate the metal surface of a substrate and prevent the growth of oxide or nitride films on the metal surface in a film deposition step that follows the surface passivation. Metal surfaces may include, but are not limited to, Au, Pd, Rh, Ru, W, Mo, Al, Ni, Cu, Ti, Co, Pt, and metal silicides (e.g., TiSi2, CoSi2, and NiSi2). Metal nitride films deposited on prepassivated metal surfaces may include, but are not limited to, TaN, TiN, WN, MoN, TaCN, TiCN, TaSiN, and TiSiN, and silicon nitride. Metal oxide films deposited on prepassivated metal substrates may include, but are not limited to, SiO2, SiON, HfO2, Ta2O5, ZrO2, TiO2, Al2O3, strontium barium titanate, and combinations thereof.

[0054] When utilized in such deposition methods and processes, the high purity alkynes can be delivered to a reaction chamber, such as an ALD reactor, in a variety of ways. In some cases, a liquid delivery system can be used. In other cases, a combined liquid delivery and flash vaporization process unit, such as a Turbo Vaporizer manufactured by MSP Corporation of Showaview, Minnesota, can be used to enable volumetric delivery of low volatility materials, thereby allowing reproducible transport and deposition without pyrolysis of the precursor. The formulations claimed herein can be effectively used as source reagents via direct liquid injection (DLI) to provide a vapor stream of these metal precursors into an ALD reactor.

[0055] For use in these processes, the high purity alkynes can be combined with a hydrocarbon solvent, which is particularly desirable because such solvents can be dried to sub-ppm water content. Exemplary hydrocarbon solvents that can be used for the precursors include, but are not limited to, toluene, mesitylene, cumene (isopropylbenzene), p-cymene (4-isopropyltoluene), 1,3-diisopropylbenzene, octane, dodecane, 1,2,4-trimethylcyclohexane, n-butylcyclohexane, and decahydronaphthalene (decalin). In some embodiments, the hydrocarbon solvent is a high boiling solvent or has a boiling point of 100° C. or higher.

[0056] A flow of argon and / or other gases may be used as a carrier gas to help deliver the vapor containing the claimed formulation into the reaction chamber during formulation pulses. When delivering the high purity alkynes, the reaction chamber process pressure is between 1 and 100 Torr, preferably between 5 and 20 Torr.

[0057] Substrate temperature can be one of the important process variables in the passivation of metal-containing films. Typical substrate temperatures range from about 150° C. to about 350° C.

[0058] In one aspect, the disclosed and claimed invention includes a method of treating a metal surface in the presence of at least one other surface, the method comprising the steps of: a. providing said at least one surface of a substrate in a reaction vessel; b. forming at least one passivated surface by exposing said at least one surface to the disclosed and claimed high purity alkynes; Includes.

[0059] In step (b), the at least one surface is passivated by exposing the at least one surface to one or more of the disclosed and claimed high purity alkynes to form a passivating film on the at least one surface. In yet another aspect of this embodiment, the method includes depositing a nitride film on the at least one passivated surface. In yet another aspect of this embodiment, the method includes depositing an oxide film on the at least one passivated surface.

[0060] In one embodiment, the method includes depositing one or more precursors known in the art as a film on a passivated film using an atomic layer deposition process (ALD), including plasma enhanced ALD (PEALD). As used herein, the term "atomic layer deposition process" or ALD refers to a self-limiting (e.g., constant amount of film material deposited in each reaction cycle) continuous surface chemistry that deposits a film of material on a substrate of various compositions. Although the precursors, reagents, and sources used herein are sometimes described as "gaseous", it is understood that the precursors can be liquid or solid that are transported into the reactor via direct vaporization, bubbling, or sublimation, with or without an inert gas. In some cases, the vaporized precursors can be passed through a plasma generator. As used herein, the term "reactor" includes, but is not limited to, a reaction chamber, a reaction vessel, or a deposition chamber.

[0061] In yet another aspect of this embodiment, the method includes introducing at least one reactant into the reaction vessel, the at least one reactant being selected from the group of water, dioxygen, oxygen plasma, ozone, NO, NO, NO, NO, carbon monoxide, carbon dioxide, and combinations thereof. In another aspect of this embodiment, the method includes introducing at least one reactant into the reaction vessel, the at least one reactant being selected from the group of ammonia, hydrazine, monoalkylhydrazine, dialkylhydrazine, nitrogen, nitrogen / hydrogen, ammonia plasma, nitrogen plasma, nitrogen / hydrogen plasma, and combinations thereof. In another aspect of this embodiment, the method includes introducing at least one reactant into the reaction vessel, the at least one reactant being selected from the group of hydrogen, hydrogen plasma, a mixture of hydrogen and helium, a mixture of hydrogen and argon, hydrogen / helium plasma, hydrogen / argon plasma, a boron-containing compound, a silicon-containing compound, and combinations thereof.

[0062] The deposition methods and processes may also include one or more purge gases. The purge gas used to purge unconsumed reactants and / or reaction by-products is an inert gas that does not react with the precursor. Exemplary purge gases include, but are not limited to, argon (Ar), nitrogen (N2), helium (He), neon, and mixtures thereof. For example, a purge gas such as Ar is fed into the reactor at a flow rate ranging from about 10 sccm to about 2000 sccm for about 0.1 seconds to about 10,000 seconds to purge unreacted materials and by-products that may remain in the reactor.

[0063] The deposition methods and processes require the addition of energy to at least one of the precursors, oxidizers, other precursors, or combinations thereof to induce a reaction and form a metal-containing film or coating on the substrate. Such energy can be provided by, but is not limited to, thermal, plasma, pulsed plasma, helicon plasma, high density plasma, inductively coupled plasma, x-ray, electron beam, photon, remote plasma methods, and combinations thereof. In some processes, a secondary RF frequency source can be used to modify the plasma characteristics at the substrate surface. When utilizing plasma, the plasma generation process can include direct plasma generation processes, where the plasma is generated directly in the reactor, or alternatively, remote plasma generation processes, where the plasma is generated outside the reactor and fed into the reactor.

[0064] When utilized in such deposition methods and processes, suitable precursors can be delivered into a reaction chamber, such as an ALD reactor, in a variety of ways. In some cases, a liquid delivery system can be used. In other cases, a combined liquid delivery and flash vaporization process unit, such as a Turbo Vaporizer manufactured by MSP Corporation of Showaview, Minnesota, can be used to enable volumetric delivery of low volatility materials, thereby allowing reproducible transport and deposition without pyrolysis of the precursor. The precursor compositions described herein can be effectively used as source reagents via direct liquid injection (DLI) to provide a vapor stream of these metal precursors into an ALD reactor.

[0065] For use in these deposition methods and processes, the precursors can be combined with a hydrocarbon solvent, which is particularly desirable because such solvents can be dried to sub-ppm water content. Exemplary hydrocarbon solvents that can be used for the precursors include, but are not limited to, toluene, mesitylene, cumene (isopropylbenzene), p-cymene (4-isopropyltoluene), 1,3-diisopropylbenzene, octane, dodecane, 1,2,4-trimethylcyclohexane, n-butylcyclohexane, and decahydronaphthalene (decalin). In some embodiments, the hydrocarbon solvent is a high boiling solvent or has a boiling point of 100° C. or higher. The precursors can also be mixed with other suitable metal precursors, and the mixture is used to simultaneously deliver both metals for the growth of bimetallic-containing films.

[0066] A flow of argon and / or other gases may be used as a carrier gas to help deliver the precursor-containing vapor to the reaction chamber during the precursor pulse. When delivering the precursor, the reaction chamber process pressure is between 1 and 50 Torr, preferably between 5 and 20 Torr.

[0067] Substrate temperature can be one of the important process variables in the deposition of high quality metal-containing films. Typical substrate temperatures range from about 150° C. to about 550° C. Higher temperatures can promote faster film growth rates.

[0068] In view of the above, one of ordinary skill in the art will appreciate that the disclosed and claimed invention includes the use of the disclosed and claimed formulations in chemical vapor deposition (CVD) processes as follows.

[0069] In one aspect, the disclosed and claimed invention includes a method of forming a metal-containing film on at least one surface of a substrate, the method comprising the steps of: a. providing said at least one surface of a substrate in a reaction vessel; b. forming at least one passivated surface by exposing said at least one surface to one or more of the disclosed and claimed high purity alkynes; and c. forming a transition metal-containing film on the at least one pre-passivated surface by a chemical vapor deposition (CVD) process using one or more precursors during a deposition process; Includes.

[0070] In step (b), the at least one surface is passivated by exposing the at least one surface to one or more of the disclosed and claimed high purity alkynes to form a passivating film on the at least one surface. In yet another aspect of this embodiment, the method includes introducing at least one reactant into the reaction vessel. In yet another aspect of this embodiment, the method includes introducing at least one reactant into the reaction vessel, the at least one reactant being selected from the group of water, dioxygen, oxygen plasma, ozone, NO, NO, NO, NO, carbon monoxide, carbon dioxide, and combinations thereof. In another aspect of this embodiment, the method includes introducing at least one reactant into the reaction vessel, the at least one reactant being selected from the group of ammonia, hydrazine, monoalkylhydrazine, dialkylhydrazine, nitrogen, nitrogen / hydrogen, ammonia plasma, nitrogen plasma, nitrogen / hydrogen plasma, and combinations thereof. In another aspect of this embodiment, the method includes introducing at least one reactant into a reaction vessel, where the at least one reactant is selected from the group of hydrogen, hydrogen plasma, a mixture of hydrogen and helium, a mixture of hydrogen and argon, hydrogen / helium plasma, hydrogen / argon plasma, a boron-containing compound, a silicon-containing compound, and combinations thereof.

[0071] In one aspect, the disclosed and claimed invention includes a method of forming a metal-containing film via a thermal atomic layer deposition (ALD) process or a thermal ALD-like process, the method comprising the steps of: a. providing a substrate in a reaction vessel; b. forming at least one passivated surface by exposing the at least one surface to one or more of the high purity alkynes disclosed and claimed; c. purging the reaction vessel with a first purge gas; d. introducing one or more precursors into the reaction vessel; e. introducing a source gas into the reaction vessel; f. purging the reaction vessel with a second purge gas; and g. successively repeating steps c through f until a desired thickness of the transition metal-containing film is obtained; Includes.

[0072] In step (b), the at least one surface is passivated by exposing the at least one surface to one or more of the disclosed and claimed high purity alkynes to form a passivating film on the at least one surface. In yet another aspect of this embodiment, the source gas is one or more oxygen-containing source gases selected from water, dioxygen, ozone, NO, NO, NO, NO, carbon monoxide, carbon dioxide, and combinations thereof. In another aspect of this embodiment, the source gas is one or more nitrogen-containing source gases selected from ammonia, hydrazine, monoalkylhydrazine, dialkylhydrazine, nitrogen, nitrogen / hydrogen, ammonia plasma, nitrogen plasma, nitrogen / hydrogen plasma, and mixtures thereof. In yet another aspect of this embodiment, the first and second purge gases are each independently selected from one or more of argon, nitrogen, helium, neon, and combinations thereof. In yet another aspect of this embodiment, the method further comprises applying energy to the one or more precursors, source gases, substrates, and combinations thereof, where the energy is one or more of thermal, plasma, pulsed plasma, helicon plasma, high density plasma, inductively coupled plasma, x-ray, electron beam, photon, remote plasma, and combinations thereof. In yet another aspect of this embodiment, step b of the method further comprises introducing one or more of the disclosed and claimed formulations into the reaction vessel using a flow of carrier gas to deliver vapor of one or more of the disclosed and claimed formulations into the reaction vessel. In yet another aspect of this embodiment, step b of the method further comprises using a solvent comprising one or more of toluene, mesitylene, isopropylbenzene, p-cymene (4-isopropyltoluene), 1,3-diisopropylbenzene, octane, dodecane, 1,2,4-trimethylcyclohexane, n-butylcyclohexane, and decahydronaphthalene (decalin), and combinations thereof.

[0073] In one aspect of this disclosure, the precursors may be used to codeposit a multicomponent oxide film, which may include oxides of two or more elements selected from magnesium, calcium, strontium, barium, aluminum, gallium, indium, titanium, zirconium, hafnium, vanadium, niobium, tantalum, molybdenum, tungsten, tellurium, and antimony.

[0074] Examples of precursors and co-precursors include, but are not limited to, trimethylaluminum, tetrakis(dimethylamido)titanium, tetrakis(ethylmethylamino)zirconium, tetrakis(ethylmethylamido)hafnium, pentakis(dimethylamido)tantalum, and tris(isopropylcyclopentadienyl)lanthanum. EXAMPLES

[0075] Below, more specific aspects of the disclosure and experimental results supporting such aspects are described. Below, examples are provided to more fully explain the disclosed and claimed invention, but should not be construed as in any way limiting the disclosed invention.

[0076] It will be apparent to those skilled in the art that various modifications and variations can be made to the disclosed invention and the specific examples provided herein without departing from the spirit or scope of the disclosed invention. Thus, the disclosed invention, including the description provided by the following examples, is intended to cover modifications and variations of the disclosed invention that come within the scope of any claims and their equivalents.

[0077] Materials and Methods: All reactions and manipulations described in the examples were carried out under a nitrogen atmosphere using an inert atmosphere glove box or standard Schlenk techniques. Unless otherwise indicated, all reagents were purchased from Sigma-Aldrich and used as received without further purification. The computer simulation program Dmol3 from Biovia using M11-L / DNP density functional theory was used to calculate and verify the adsorption properties of the disclosed and claimed invention. The high purity alkynes were characterized by Karl Fischer titration, GC-FID and GC-ECD. In the table below the following abbreviations are used in the various compositions:

[0078] [Table 4]

[0079] Examples Example 1: Adsorption of 5-decyne on a "bare" copper surface This example evaluates the adsorption of 5-decyne (3E) on "bare" copper surfaces. 5-Decyne was calculated to chemisorb strongly on the copper(100) surface with an adsorption energy of -43 kcal / mol and on the copper(111) surface with an adsorption energy of -40 kcal / mol.

[0080] Example 2: Adsorption of 5-decyne (3E) on copper(I) oxide This example calculates the adsorption of 5-decyne (3E) on hydroxyl-rich copper(I) and copper(II) oxides. Copper(I) oxide (Cu2O) is a common impurity on metallic copper. The results show that 5-decyne adsorption on hydroxyl-rich Cu2O is weak (i.e., the adsorption energy is only -6.3 kcal / mol). Therefore, it is expected to passivate Cu2O sites on the copper surface with little or no effect. Therefore, it is important to minimize and / or eliminate water (and other impurities) in 5-decyne and other alkynes, as they can lead to the formation of Cu2O sites on the copper surface, thereby inhibiting surface passivation with 5-decyne and other alkynes.

[0081] [Table 5]

[0082] Example 3: Adsorption of 1-bromobutane and dibromobutane on "bare" copper surfaces This example evaluated the adsorption of 1-bromobutane and dibromobutane on a "bare" copper surface. 1-bromobutane and dibromobutane, respectively, are occasionally used in the synthesis of substituted alkynes. However, their use can lead to the presence of residual halogen impurities in the synthesized alkynes. It was calculated that 1-bromobutane and dibromobutane strongly chemisorb onto a copper (100) surface with adsorption energies of -21.4 kcal / mol for 1-bromobutane, -24.4 kcal / mol for 1,2-dibromobutane, and -26.1 kcal / mol for 1,4-dibromobutane, respectively. The adsorption is dissociative; it cleaves the bromide-carbon bond, resulting in a copper surface contaminated with bromide, which inhibits passivation of the copper surface with alkynes. Therefore, high purity alkynes, substantially free of alkyl halides, including alkyl bromides, are desirable for selective deposition.

[0083] Example 4: Preparation of high-purity 5-decyne (3E) High-purity 5-decyne substantially free of water was produced by recycling 3 kg of 5-decyne through a column packed with 300 g of 3 Å molecular sieves. As analyzed by Karl Fischer titration, the water content in 5-decyne before purification was more than 50 ppm, and after purification it was 15 ppm.

[0084] Example 5: Preparation of high-purity 5-decyne (3E) High purity 5-decyne was produced by distilling 14.4 kg of 5-decyne through a column of Pro-Pak® distillation packing. The purity of 5-decyne was 99.7% before purification and 99.92% after purification as analyzed by GC-FID. The 1,4-dibromobutane content was 257 ppm before purification and less than 1 ppm after purification as analyzed by a combination of GC-FID and GC-ECD. The 1-bromobutane content was 72 ppm before purification and 0.02 ppb after purification as analyzed by a combination of GC-ECD and GC-MS.

[0085] Example 6: Comparison of copper passivation using high-purity 5-decyne (3E) and 5-decyne (3E) with added bromobutane In this experiment, a sample of high-purity 5-cyne and a sample of high-purity 5-cyne spiked with 1,4-dibromobutane were used to verify the passivation of the Cu surface. The high-purity 5-cyne was purified by the methods described in Examples 4 and 5. The amount of residual 1,4-dibromobutane was less than 1.5 ppm as measured by GC-MS. A spiked sample was produced by spiked with 1000 ppm of 1,4-bromobutane to the purified 5-cyne sample.

[0086] PVD Cu coupons from ADVACTIV Technologies were used for the tests. The coupons were loaded into the reactor chamber and pre-cleaned by treatment with hydrogen gas at 350°C for 600 seconds under 1.75 torr chamber pressure to remove residual surface oxide. After this step, the coupons were exposed to 5-decyne vapor at 250°C for 180-300 seconds. In one experiment, high purity 5-decyne was used, and in the other experiment, 5-decyne with added 1,4-bromobutane was used. After the exposure, the coupons were transferred to another process chamber without exposure to air. The coupons were exposed to 25 ALD cycles for the deposition of TaN films. Cycle conditions: pentakis(dimethylamido)tantalum pulse for 2 seconds; Ar purge for 20 seconds; NH3 pulse for 7 seconds; Ar purge for 20 seconds. TaN films were deposited at a wafer temperature of 250°C and a chamber pressure of 1 torr.

[0087] The amount of Ta deposited on the Cu surface passivated with high-purity 5-decyne and added 5-decyne was measured by XPS. Figure 3 shows the integrated area of ​​the Ta XPS peak for two different exposure times (SAM grafting times) of 180 seconds and 300 seconds. In both cases, the amount of Ta deposited on the Cu surface passivated with high-purity 5-decyne was significantly less than that of the Cu surface passivated with added decyne. This experiment shows that high-purity 5-decyne, which is substantially free of haloalkanes (e.g., bromoalkanes), provides a much better passivation of the Cu surface.

[0088] It is anticipated that the disclosed and claimed methods may also be used with deposition tools typically found at semiconductor manufacturing sites for the production of molybdenum-containing layers for logic applications and other possible functions.

[0089] The foregoing description is intended primarily for purposes of illustration. Although the disclosed and claimed invention has been illustrated and described with respect to exemplary embodiments thereof, it should be understood by those skilled in the art that various other changes, omissions and additions thereto in form and detail may be made without departing from the spirit and scope of the disclosed and claimed invention.

Claims

1. 1. A method for forming a metal-containing film via a chemical vapor deposition (CVD) process, comprising: a. providing at least one substrate in a reaction vessel; b) forming at least one passivated surface by exposing at least one surface of said at least one substrate to one or more high-purity alkynes or formulations thereof, said one or more high-purity alkynes or formulations thereof having a concentration of halogen-containing impurities of less than about 100 ppm, where "about" refers to within ±5% of the stated value; c. forming a metal-containing film on the at least one passivated surface using one or more precursors during a deposition process; The method comprising:

2. 1. A method for forming a metal-containing film via a thermal atomic layer deposition (ALD) process, comprising: a. providing at least one substrate in a reaction vessel; b) forming at least one passivated surface by exposing at least one surface of said at least one substrate to one or more high-purity alkynes or formulations thereof, said one or more high-purity alkynes or formulations thereof having a concentration of halogen-containing impurities of less than about 100 ppm, where "about" corresponds to within ±5% of the stated value; c. purging the reaction vessel with a first purge gas; d. introducing one or more precursors into the reaction vessel; e. introducing a source gas into the reaction vessel; f. purging the reaction vessel with a second purge gas; and g. successively repeating steps c through f until a desired thickness of the metal-containing film is obtained; The method comprising:

3. 10. The method of claim 1, further comprising depositing a multicomponent oxide film on the at least one passivated surface, wherein the multicomponent oxide film comprises oxides of two or more elements selected from magnesium, calcium, strontium, barium, aluminum, gallium, indium, titanium, zirconium, hafnium, vanadium, niobium, tantalum, molybdenum, tungsten, tellurium, and antimony.

4. The method of claim 2, further comprising depositing a multi-component oxide film on the at least one passivated surface, wherein the multi-component oxide film comprises oxides of two or more elements selected from magnesium, calcium, strontium, barium, aluminum, gallium, indium, titanium, zirconium, hafnium, vanadium, niobium, tantalum, molybdenum, tungsten, tellurium, and antimony.

5. The method of claim 1, wherein the one or more high-purity alkynes or preparations thereof have a concentration of halogen-containing impurities of less than about 50 ppm, where "about" corresponds to within ±5% of the stated value.

6. The method of claim 2, wherein the one or more high-purity alkynes or preparations thereof have a concentration of halogen-containing impurities of less than about 50 ppm, where "about" corresponds to within ±5% of the stated value.

7. The method of claim 1, wherein the one or more high-purity alkynes or preparations thereof have a concentration of halogen-containing impurities of less than about 10 ppm, where "about" corresponds to within ±5% of the stated value.

8. The method described in claim 2, wherein the one or more high-purity alkynes or preparations thereof have a concentration of halogen-containing impurities of less than about 10 ppm, where "about" corresponds to within ±5% of the stated value.

9. The method of claim 1, wherein the one or more high-purity alkynes or preparations thereof have a water concentration of less than about 50 ppm, where "about" corresponds to within ±5% of the stated value.

10. The method of claim 2, wherein the one or more high-purity alkynes or preparations thereof have a water concentration of less than about 50 ppm, where "about" corresponds to within ±5% of the stated value.

11. The method of claim 1, wherein the one or more high-purity alkynes or preparations thereof have a concentration of carboxylic acids of less than about 500 ppm, where "about" corresponds to within ±5% of the stated value.

12. The method of claim 2, wherein the one or more high-purity alkynes or preparations thereof have a concentration of carboxylic acids of less than about 500 ppm, where "about" corresponds to within ±5% of the stated value.

13. The method of claim 1, wherein the one or more high purity alkynes or preparations thereof have a concentration of halogen-containing impurities of less than about 10 ppm, a concentration of water of less than about 10 ppm, and a concentration of carboxylic acids of less than about 100 ppm, wherein "about" corresponds to within ±5% of the stated values.

14. The method of claim 2, wherein the one or more high purity alkynes or preparations thereof have a concentration of halogen-containing impurities of less than about 10 ppm, a concentration of water of less than about 10 ppm, and a concentration of carboxylic acids of less than about 100 ppm, where "about" corresponds to within ±5% of the stated values.

15. The method of claim 1, wherein the one or more high-purity alkynes or preparations thereof comprise one or more of the following: Table 1 16. The method of claim 2, wherein the one or more high-purity alkynes or preparations thereof comprise one or more of the following: Table 2 17. The method of claim 1, wherein the one or more high-purity alkynes or preparations thereof include one or more of 5-decyne (3E), 1-decyne (3A), 4-octyne (1X), 1-octyne (1U), 3-hexyne (1I), and 1-hexyne (1G).

18. The method of claim 2, wherein the one or more high-purity alkynes or preparations thereof include one or more of 5-decyne (3E), 1-decyne (3A), 4-octyne (1X), 1-octyne (1U), 3-hexyne (1I), and 1-hexyne (1G).

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