Compositions for Depositing Silicon-Containing Films and Methods Using the Same

Abstract

The composition and method are used to form a silicon-containing film, such as, but not limited to, a silicon carbide, silicon oxynitride, carbon-doped silicon nitride, carbon-doped silicon oxide, or carbon-doped silicon oxynitride film, on at least one surface of a substrate having surface features. The silicon-containing film is deposited using an alkylhydridosilane compound containing at least one Si-H bond.

Description

Technical Field

[0001] Described herein is a process for the manufacture of electronic devices. More specifically, described herein is a composition for forming a silicon-containing film during a deposition process such as, but not limited to, a fluidized chemical vapor deposition process. Exemplary silicon-containing films that can be deposited using the compositions and methods described herein include, but are not limited to, silicon carbide, silicon oxynitride, carbon-doped silicon oxide, or carbon-doped silicon nitride films.

Background Art

[0002] U.S. Patent Application Publication No. 2013 / 0217241 discloses the deposition and treatment of Si-C-N-containing fluidized layers. Si and C can be derived from Si-C-containing precursors, while N can be derived from N-containing precursors. The initial Si-C-N-containing fluidized layer is treated to remove components that enable fluidity. Removal of these components can increase etch resistance, reduce shrinkage, and adjust film stress and electrical properties. The post-treatment can be thermal annealing, UV exposure, or high-density plasma.

[0003] U.S. Patent No. 8889566 discloses a method for depositing a fluidized film by exciting a silicon precursor with a local plasma and depositing with a second plasma. The silicon precursor can be a silylamine, a higher-order silane, or a halogenated silane. The second reaction gas can be NH 3 , N 2 , H 2 and / or O 2 .

[0004]

[0005] U.S. Patent No. 7825040 discloses a method for filling gaps by introducing an alkoxysilane or aminosilane precursor and depositing a fluidized Si-containing film by plasma reaction. The precursor does not contain Si-C or C-C bonds.U.S. Pat. Nos. 8,889,566, 7,521,378, and 8,575,040 describe an approach for depositing silicon oxide films using a fluidized chemical vapor deposition process to achieve vapor phase polymerization. Compounds such as trisilylamine (TSA) are used to deposit Si, H, and N-containing oligomers, and these oligomers are then oxidized to SiO x films using ozone exposure.

[0006] U.S. Pat. No. 8,846,536 discloses a method for depositing and modifying a fluid dielectric film. The wet etching rate of the fluid dielectric film can be varied by at least a factor of 10 by one or more integrated processes.

[0007] The disclosures of the patents and patent applications specifically identified above are incorporated herein by reference. SUMMARY OF THE INVENTION PROBLEMS TO BE SOLVED BY THE INVENTION

[0008] Despite recent activity in the technical fields related to fluidized chemical vapor deposition and other film deposition processes, problems still remain. One of these problems relates to film stress and void formation. Fluid films are mainly deposited at relatively low temperatures, but high-temperature, high-energy post-treatment leads to high film stress and creates voids in the features. Since the film quality is low at low process temperatures, reducing the wet etching rate has continued to be a challenge. Therefore, there is a need to provide alternative precursor compounds, precursor combinations, or modified techniques or combinations thereof. MEANS FOR SOLVING THE PROBLEMS

[0009] The compositions or formulations described herein and the methods using them overcome the problems of the prior art by depositing a silicon-containing film on at least a portion of the substrate surface that provides desirable film properties at the time of post-deposition processing. The inventive compositions and methods can provide a silicon-containing film having the following properties: i) a film tensile stress in the range of about 10 to about 20 MPa after thermal curing and in the range of about 150 to about 190 MPa after UV curing, when measured using a TOKYO SEIMITSU stress tool, and ii) a density of about 1.35 to about 2.10 g / cm 3 as measured by X-ray reflectivity. The film in the as-deposited state is fluid and can fill features having an aspect ratio of 2:1 or greater and less than 50 nm in width, and can be fully annealed using an energy source such as, but not limited to, heat, UV light, or an electron beam. The annealed film is stable to air and does not result in the formation of voids within the features.

[0010] The silicon-containing film is selected from the group consisting of silicon carbide, silicon oxide, carbon-doped silicon nitride, and carbon-doped oxynitride films. In some embodiments, the substrate includes surface features. As used herein, the term "surface features" means a substrate or a partially fabricated substrate that includes one or more of pores, trenches, shallow trench isolation (STI), vias, reentrant features, and the like. The composition can be a premixed composition (mixed prior to use in the deposition process) or an in-situ mixture (mixed during the deposition process). Thus, in the present disclosure, the terms "mixture", "formulation", and "composition" are interchangeable.

[0011] In one aspect, in a method of depositing a silicon-containing film, placing a substrate having surface features in a reactor at one or more temperatures in the range of -20°C to about 200°C; and introducing into the reactor a compound having at least one silicon-hydrogen bond and having the formula R n SiH 4-n wherein R is a linear or branched C2 ~C 6 alkyl or C 6 ~C 10 selected independently from aryl groups, where n is a number selected from 1, 2, or 3; providing a plasma source in a reactor and at least partially reacting a compound to form a fluid liquid or oligomer, where the fluid liquid or oligomer at least partially fills a portion of the surface features; A method comprising is provided.

[0012] In one particular embodiment, the plasma source is selected from the group consisting of nitrogen plasma; plasma containing nitrogen and helium; plasma containing nitrogen and argon; ammonia plasma; plasma containing ammonia and helium; plasma containing ammonia and argon; helium plasma; argon plasma; hydrogen plasma; plasma containing hydrogen and helium; plasma containing hydrogen and argon; plasma containing ammonia and hydrogen; organic amine plasma; plasma containing oxygen; plasma containing oxygen and hydrogen, and mixtures thereof.

[0013] In another embodiment, the plasma source is selected from the group consisting of hydrocarbon plasma, plasma containing hydrocarbon and helium, plasma containing hydrocarbon and argon, carbon dioxide plasma, carbon monoxide plasma, plasma containing hydrocarbon and hydrogen, plasma containing hydrocarbon and a nitrogen source, plasma containing hydrocarbon and an oxygen source, and carbon source plasmas including mixtures thereof.

[0014] The plasma source can be an in-situ source or a remote source such as a remote microwave or remote plasma source.

[0015] In any of the above embodiments or a modified embodiment, the method further includes subjecting at least a portion of the deposited material to a heat treatment at one or more temperatures within the range of about 100 °C to about 1000 °C to densify the at least a portion of the deposited material.

[0016] According to another exemplary embodiment, the material after heat treatment is exposed to plasma, infrared light, chemical treatment, electron beam or UV light to form a high density film.

[0017] Some or all of the above steps define a cycle, and this cycle can be repeated until the desired thickness of the silicon-containing film is obtained. In this or other embodiments, each step of the method described herein can be performed in various orders, sequentially or simultaneously (e.g., during at least a portion of another step), and these can be combined. Each step of supplying the compound and other reagents can be performed by varying the duration of their supply to change the stoichiometric composition of the resulting silicon-containing film.

[0018] Another embodiment of the present invention relates to a film formed by an inventive method and a film having the previously identified properties.

[0019] The various embodiments of the present invention can be used alone or in combination with each other.

Brief Description of the Drawings

[0020]

Figure 1

Modes for Carrying Out the Invention

[0021] Described herein is a method of utilizing an alkylhydridosilane compound to deposit a flowable film via a chemical vapor deposition (CVD) process on at least a portion of a substrate having surface features. As previously discussed, films deposited by flowable CVD are often prone to film shrinkage during post-processing due to low process temperatures. Voids and seams may form in such films due to significant film shrinkage and increased film stress. Thus, it has been difficult to densify films without increasing film stress or creating voids. The method described herein overcomes these problems by improving the filling of at least a portion of the surface features on the substrate. The method includes depositing a flowable film by a chemical vapor deposition (CVD) process in which R is a linear or branched C 2 ~C 6 Alkyl or C 6 ~C 10 aryl groups, and n is a number selected from 1, 2, and 3; n SiH 4-n The reaction is carried out using an alkylhydridosilane precursor compound having the formula: Exemplary precursor compounds include, but are not limited to, ethylsilane, diethylsilane, triethylsilane, isopropyldiethylsilane, phenyldiethylsilane, and benzyldiethylsilane.

[0022] In the above formula and throughout this specification, the term "linear or branched alkyl" refers to a straight chain functional group having 2 to 6 carbon atoms. Exemplary linear or branched alkyl groups include, but are not limited to, ethyl (Et), isopropyl (Pr), ... i ), isobutyl (Bu i ), sec-Butyl (Bu s ), tert-Butyl (Bu t) include iso-pentyl, tert-pentyl(am), isohexyl, and neohexyl. In some embodiments, the alkyl group may have one or more functional groups attached thereto, such as, but not limited to, an alkoxy group, a dialkylamino group, or a combination thereof. In other embodiments, the alkyl group has no one or more functional groups attached thereto. The alkyl group may be saturated or alternatively unsaturated.

[0023] Throughout the above formulas and throughout this specification, the term "cyclic alkyl" means a cyclic group having 3 to 10 atoms. Exemplary cyclic alkyl groups include, but are not limited to, cyclobutyl, cyclopentyl, cyclohexyl, and cyclooctyl groups. In some embodiments, the cyclic alkyl group has a straight-chain or branched substituent of 3 to 10 atoms or a substituent containing an oxygen or nitrogen atom. The cyclic alkyl group may have as a substituent one or more straight-chain or branched alkyl or alkoxy groups, such as a methylcyclohexyl group or a methoxycyclohexyl group.

[0024] Throughout the above formulas and throughout this specification, the term "aryl group" means a group having 3 to 10 atoms. Exemplary aryl groups include, but are not limited to, methylbenzene, benzyl, and phenyl.

[0025] In some embodiments, one or more of the alkyl groups in the formula may be "substituted" or may have one or more atoms or groups of atoms substituted, for example, in place of a hydrogen atom. Exemplary substituents include, but are not limited to, oxygen, sulfur, halogen atoms (such as F, Cl, I, or Br), nitrogen, alkyl groups, and phosphorous acid.

[0026] The silicon precursor compounds described herein can be delivered in various forms to a reaction chamber such as a CVD or ALD reactor. In one embodiment, a liquid delivery system is used. In a variant embodiment, a combined liquid delivery and flash vaporization process unit, such as a turbo vaporizer manufactured by MSP Corporation of Shoreview, MN, is utilized to volumetrically deliver low volatility materials, thus leading to reproducible transport and deposition without thermal decomposition of the precursor. In liquid delivery formulations, the precursors described herein can be delivered in neat liquid form or alternatively utilized in a solvent formulation or composition containing the same. Thus, in some embodiments, the precursor formulation contains a solvent component having suitable properties that are desirable and advantageous for forming a film on a substrate in a given end-use application area. Examples of suitable solvents include at least one member selected from the group consisting of nonpolar alkane solvents such as cyclohexane and cyclohexanone.

[0027] The silicon precursor compound preferably substantially does not contain halide ions such as chloride or metal ions such as Al. As used herein, the term "substantially does not contain" in relation to halide ions (or halides), such as chloride and fluoride, bromide, iodide, Al 3+ ions, Fe 2+ , Fe 3+ , Ni 2+ , Cr 3+ means less than 5 ppm (by mass), preferably less than 3 ppm, more preferably less than 1 ppm, and most preferably 0 ppm. Chloride or metal ions are known to act as decomposition catalysts for silicon precursors. A significant level of chloride in the final product can cause degradation of the silicon precursor. The progressive degradation of the silicon precursor directly affects the film deposition process and can make it difficult for semiconductor manufacturers to comply with film specifications. Furthermore, the shelf life or stability of the precursor is negatively affected when the degradation rate of the silicon precursor is high, thus making it difficult to guarantee a shelf life of 1 - 2 years.

[0028] The method used to form the films or coatings described herein is a fluidized chemical vapor deposition process. Examples of suitable deposition processes for the methods disclosed herein include, but are not limited to, circulating fluidized chemical vapor deposition (CFCVD), or plasma-enhanced fluidized chemical vapor deposition (PEFCVD), remote activated chemical vapor deposition (RACVD). The term "fluidized chemical vapor deposition process" as used herein refers to exposing a substrate to one or more volatile precursors that react and / or decompose above or on the substrate surface to provide a fluidized oligomeric silicon-containing species that then produces a solid film or material at the point of further processing, and in some cases at least a portion of the oligomeric species contains polymeric species, and any process where the precursors, reagents, and feeds, although sometimes described as "gaseous", are understood to be either liquids or solids that are transported into the reactor with or without an inert gas via direct vaporization, bubbling, or sublimation. In some cases, the vaporized precursors pass through a plasma generator. In one embodiment, the film is deposited using a plasma-based (e.g., remote generated or in-situ) CVD process. The term "reactor" as used herein includes, but is not limited to, a reaction chamber or deposition chamber.

[0029] The precursor compounds described herein can be delivered to a fluidized chemical vapor deposition reactor in a variety of ways, including, but not limited to, vapor draw, bubbling, or direct liquid injection (DLI). In one embodiment, a liquid delivery system may be used. In another embodiment, the reactor may be equipped with a dual-plenum showerhead to keep remotely generated plasma species separated from the vapor of the precursor until they are combined within the reactor to deposit a flowing liquid. In a variant embodiment, a combined liquid delivery and flash vaporization process unit, such as a turbo vaporizer manufactured by MSP Corporation of Shoreview, MN, may be utilized to volumetrically deliver low volatility materials, thus leading to reproducible transport and deposition without thermal decomposition of the precursor. In liquid delivery formulations, the precursors described herein can be delivered in neat liquid form or alternatively utilized in a solvent formulation or composition containing the same. Thus, in some embodiments, the precursor formulation may include a solvent component having suitable properties that are desirable and advantageous for forming a film on a substrate in a given end-use application area.

[0030] In some embodiments, the substrate can be exposed to one or more pre-deposition treatments, including, but not limited to, plasma treatment, heat treatment, chemical treatment, ultraviolet light exposure, electron beam exposure, and combinations thereof, to affect one or more properties of the film. These pre-deposition treatments can be performed under an atmosphere selected from inert, oxidative, and / or reductive.

[0031] Energy is applied to at least one of a precursor compound, a nitrogen-containing source, an oxygen source, a hydrogen source, other precursors, or combinations thereof to induce a reaction and form a silicon-containing film or coating on a substrate. Such energy can be provided, without limitation, by heat, plasma, pulsed plasma, helicon plasma, high density plasma, inductively coupled plasma, X-rays, e-beams, photons, remote plasma methods, and combinations thereof. In some embodiments, a secondary RF frequency source can be used to modify plasma characteristics at the substrate surface. In embodiments where plasma is involved in the deposition, the plasma generation process can include a direct plasma generation process in which plasma is generated directly within the reactor, or alternatively, a remote plasma generation process in which plasma is generated outside the reactor and supplied into the reactor.

[0032] As previously mentioned, the method deposits a film on at least a portion of the surface of a substrate that includes surface features. The substrate is disposed within a reactor and the substrate is maintained at one or more temperatures within the range of about -20 °C to about 200 °C. In one particular embodiment, the temperature of the substrate is lower than the walls of the chamber. For the purpose of limiting film shrinkage during curing, it may be advantageous to deposit a flowable film at the maximum temperature at which flowability is exhibited, preferably at a temperature below 150 °C.

[0033] As mentioned above, the substrate includes one or more surface features. In one particular embodiment, the surface features have a width of 1 μm or less, or 500 nm or less, or 50 nm or less or 10 nm. In this or other embodiments, when surface features are present, their aspect ratio (depth to width ratio) is 0.1:1 or more or 1:1 or more or 10:1 or more, or 20:1 or more, or 40:1 or more. The substrate can be a single crystal silicon wafer, a silicon carbide wafer, an aluminum oxide (sapphire) wafer, a glass sheet, a metal foil, an organic polymer film, or alternatively, a three-dimensional item made of polymer, glass, silicon or metal. The substrate can be coated with various materials well-known in the art, including films such as silicon oxide, silicon nitride, amorphous carbon, silicon oxycarbide, silicon oxynitride, silicon carbide, gallium arsenide, gallium nitride. These coatings may completely cover the substrate, may be made up of multiple layers of various materials, and may be partially etched to expose underlying material layers. Similarly, the surface has a photoresist material on top that is exposed and developed in a certain pattern to partially coat the substrate.

[0034] In one aspect of the present invention, the substrate comprises at least one member selected from the group consisting of Si, SiO x , SiN, SiGe, SiOC and SiON. In another aspect of the present invention, the inventive silicon-containing film can be utilized as a hard mask, providing etch selectivity with respect to the photoresist. In a further aspect of the present invention, the inventive silicon-containing film functions as a dielectric film between conductive materials, as a barrier between a conductive material and another dielectric, or as a film inside a sandwich dielectric.

[0035] In some embodiments, the reactor is at a pressure below atmospheric pressure or 750 Torr or less, or 100 Torr or less. In other embodiments, the pressure of the reactor is maintained within the range of about 0.1 Torr to about 10 Torr.

[0036] In one particular embodiment, the introduction step in which at least one compound and plasma are introduced into the reactor is carried out at one or more temperatures within the range of about -20 to about 200 °C. In these or other embodiments, the substrate includes a semiconductor substrate including surface features. The plasma containing nitrogen can be selected from the group consisting of nitrogen plasma, nitrogen / hydrogen plasma, nitrogen / helium plasma, nitrogen / argon plasma, ammonia plasma, ammonia / helium plasma, ammonia / argon plasma, ammonia / nitrogen plasma, NF 3 NF 3 plasma, organic amine plasma, and mixtures thereof. The at least one compound and the nitrogen source react to form a silicon nitride film (which is non-stoichiometric) or a silicon carbonitride film on at least a portion of the surface features and the substrate. As used herein, the term "organic amine" refers to an organic compound having at least one nitrogen atom. Examples of organic amines include, but are not limited to, methylamine, ethylamine, propylamine, isopropylamine, tert-butylamine, sec-butylamine, tert-amylamine, ethylenediamine, dimethylamine, trimethylamine, diethylamine, pyrrole, 2,6-dimethylpiperidine, di-n-propylamine, di-iso-propylamine, ethylmethylamine, N-methylaniline, pyridine, and triethylamine.

[0037] In another embodiment, the plasma source is selected from the group consisting of, but not limited to, hydrocarbon plasma, plasma containing hydrocarbon and helium, plasma containing hydrocarbon and argon, carbon dioxide plasma, carbon monoxide plasma, plasma containing hydrocarbon and hydrogen, plasma containing hydrocarbon and nitrogen source, plasma containing hydrocarbon and oxygen source, and carbon source plasma including mixtures thereof. The at least one compound and the carbon source react to form a silicon carbide film (which is non-stoichiometric) or a silicon carbonitride film on at least a portion of the surface features and the substrate.

[0038] In different embodiments, the plasma source is selected from, without limitation, hydrogen plasma, helium plasma, argon plasma, xenon plasma, and mixtures thereof. At least one compound and the plasma react to form a silicon carbide film or a silicon carbonitride film on at least a portion of the surface features and the substrate.

[0039] In some embodiments, after the silicon-containing film is deposited, the substrate is optionally treated with an oxygen-containing source under certain process conditions sufficient to form silicon oxide or silicon oxynitride on the silicon nitride film and convert the silicon carbide film to a carbon-doped silicon oxide film. The oxygen-containing source can be selected from the group consisting of water (H 2 O), oxygen (O 2 ), oxygen plasma, ozone (O 3 ), NO, N 2 O, carbon monoxide (CO), carbon dioxide (CO 2 ), N 2 O plasma, carbon monoxide (CO) plasma, carbon dioxide (CO 2 ) plasma, and combinations thereof.

[0040] In some embodiments, the fluid liquid or oligomer is treated at one or more temperatures in the range of about 100 °C to about 1000 °C to densify at least a portion of the material.

[0041] In some embodiments, the material after heat treatment is exposed to plasma, infrared light, chemical treatment, electron beam, or UV light to form a high-density film.

[0042] The above steps define one cycle for the method described herein; this cycle can be repeated until the desired thickness of the silicon-containing film is obtained. In this or other embodiments, each step of the method described herein can be performed in various orders, sequentially or simultaneously (e.g., during at least a portion of another step), or a combination thereof. Each step of supplying the compounds and other reagents can be performed by varying the duration of their supply to change the stoichiometric composition of the resulting silicon-containing film.

[0043] In one aspect, a method of depositing a silicon-containing film during a fluidized chemical vapor deposition process comprising disposing a substrate having surface features in a reactor at one or more temperatures within the range of -20 °C to about 200 °C; Formula R n SiH 4-n introducing into the reactor at least one alkylhydridosilane compound having at least one Si-H bond selected from the group consisting of: wherein R is independently selected from linear or branched C 2 ~C 6 alkyl or C 6 ~C 10 aryl groups, and n is a number selected from 1, 2, and 3; providing a plasma source in the reactor and reacting the first and second compounds at least partially to form a fluid liquid or oligomer, wherein the fluid liquid or oligomer at least partially fills a portion of the surface features; A method is provided that includes the following. The steps described above define one cycle for the method described herein; this cycle can be repeated until the desired thickness of the silicon-containing film is obtained. In this or other embodiments, each step of the method described herein can be performed in various orders, sequentially or simultaneously (e.g., during at least a portion of another step), or a combination thereof. Each step of supplying the compounds and other reagents can be performed by varying the duration of their supply to change the stoichiometric composition of the resulting silicon-containing film.

[0044] The plasma containing nitrogen can be selected from the group consisting of nitrogen plasma, nitrogen / hydrogen plasma, nitrogen / helium plasma, nitrogen / argon plasma, ammonia plasma, ammonia / helium plasma, ammonia / argon plasma, ammonia / nitrogen plasma, organic amine plasma, and mixtures thereof.

[0045] In another embodiment, the plasma source can be selected from the group consisting of, without limitation, hydrocarbon plasma, plasma containing hydrocarbon and helium, plasma containing hydrocarbon and argon, carbon dioxide plasma, carbon monoxide plasma, plasma containing hydrocarbon and hydrogen, plasma containing hydrocarbon and a nitrogen source, plasma containing hydrocarbon and an oxygen source, and carbon source plasma including mixtures thereof.

[0046] In any of the above embodiments or a variant embodiment, the plasma source can be selected from the group consisting of, without limitation, hydrogen plasma, helium plasma, argon plasma, xenon plasma, and mixtures thereof. At least one compound and the plasma react to form a silicon carbide film on at least a portion of the surface features and the substrate.

[0047] In some embodiments, after the silicon-containing film is deposited, the substrate is optionally treated with an oxygen-containing source under certain process conditions sufficient to form a silicon oxide or silicon oxynitride or carbon-doped silicon oxide film on the silicon carbide or silicon carbonitride film. The oxygen-containing source is water (H 2 O), oxygen (O 2 ), oxygen plasma, ozone (O 3 ), NO, N 2 O, carbon monoxide (CO), carbon dioxide (CO 2 ), N 2 O plasma, carbon monoxide (CO) plasma, carbon dioxide (CO 2 ) plasma, and combinations thereof.

[0048] In any of the above-described embodiments or a variant embodiment, the fluid liquid or oligomer is treated at one or more temperatures in the range of about 100 °C to about 1000 °C to densify at least a portion of the material.

[0049] In some embodiments, the material after heat treatment is exposed to plasma, infrared light, chemical treatment, electron beam, or UV light to form a high-density film. In one embodiment of the present invention, the post-treatment including exposure to UV light is performed under conditions for emitting gaseous by-products of ethylene and silane.

[0050] The following examples are provided for the purpose of illustrating some embodiments of the present invention and are not intended to limit the scope of the appended claims.

Example

[0051] A fluid chemical vapor deposition (FCVD) film was deposited on a single crystal silicon wafer substrate and a Si patterned wafer having a median resistivity (8 - 12 Ωcm). In some examples, the resulting silicon-containing film or coating can be exposed to pre-deposition treatments such as, but not limited to, plasma treatment, heat treatment, chemical treatment, ultraviolet light exposure, infrared light exposure, electron beam exposure, and / or other treatments to affect one or more properties of the film.

[0052] A fluidized chemical vapor deposition (FCVD) film was deposited on a single-crystalline silicon wafer substrate with a median resistivity (8 - 12 Ωcm) and a Si pattern wafer. For the pattern wafer, the preferred pattern width is 20 - 100 nm with an aspect ratio of 5:1 - 20:1. Deposition was carried out using a dual-plenum showerhead on a modified FCVD chamber on an Applied Materials Precision 5000 system. The chamber was equipped with a direct liquid injection (DLI) delivery capability. The precursor was a liquid, and the delivery temperature was determined by the boiling point of the precursor. To deposit the initial fluidized silicon oxide film, the typical liquid precursor flow rate was in the range of about 100 - about 5000 mg / min, preferably 1000 - 2000 mg / min; the chamber pressure was in the range of about 0.75 - 12 Torr, preferably 0.5 - 2 Torr. Specifically, the remote power was provided by an MKS microwave generator operating at a frequency of 2.455 GHz at 2 - 8 Torr with 0 - 3000 W. To densify the deposited fluidized film, the film was thermally annealed and / or UV cured in vacuum using a modified PECVD chamber at 100 - 1000 °C, preferably 300 - 400 °C. The thickness and refractive index (RI) at 632 nm were measured using an SCI reflectometer or a Woollam ellipsometer. The typical film thickness was in the range of about 10 - about 2000 nm. The bonding characteristic hydrogen content (Si - H and C - H) of the silicon-based film was measured and analyzed using a Nicolet transmission Fourier transform infrared spectroscopy (FTIR) tool. X-ray photoelectron spectroscopy (XPS) analysis was performed to determine the elemental composition of the film. A mercury probe was employed for electrical property measurements including dielectric constant, leakage current, and breakdown electric field. The fluidity and gap filling effect on the AI patterned wafer were observed by cross-sectional scanning electron microscopy (SEM) using a Hitachi S-4800 system with a resolution of 2.0 nm.

[0053] Example 1: Deposition of a fluidized silicon carbonitride film using triethylsilane (3ES) and ammonia

[0054] Triethylsilane (3ES) was used as a precursor for the deposition of a flowing SiNC film by a remote plasma source (RPS). 3ES was delivered through a showerhead that bypassed the remote microwave. The liquid flow rate was 2100 mg / min, and 200 sccm of helium was added as a carrier gas for DLI delivery. A mixture of 500 sccm of helium and 500 sccm of ammonia was flowed through the microwave applicator, while the pressure was 0.2 torr. The substrate temperature was 40 °C. The microwave power was 3000 W. The thickness and refractive index of the deposited film were 152 nm and 1.55, respectively. After thermal annealing, the thickness and refractive index were 150 nm and 1.54, respectively, showing a slight loss of volatile oligomers at high temperature. After thermal annealing, the film was UV-cured at 400 °C for 4 minutes, and the thickness and refractive index were 65 nm and 1.54, respectively.

[0055] Example 2: Deposition of a flowing silicon carbonitride film using triethylsilane (3ES) and ammonia for XPS

[0056] The fluidic film deposited from 3ES and ammonia is unstable in air and will absorb approximately 20 atomic % oxygen over time as measured by XPS. Therefore, the sample was deposited and then in-situ capped with a standard high-density silicon carbonitride PECVD film deposited using tetramethylsilane and ammonia for the purpose of obtaining the exact elemental composition of the film. 3ES was delivered through a showerhead that bypassed the remote microwave. The liquid flow rate was 2500 mg / min and 200 sccm of helium was added as a carrier gas for DLI delivery. A mixture of 500 sccm of helium and 500 sccm of ammonia was flowed through the microwave applicator and the pressure was 0.7 torr. The substrate temperature was 40 °C. The microwave power was 3000 W. The thickness and refractive index of the deposited film were 165 nm and 1.53, respectively. The sample was then thermally annealed at 300 °C for 5 minutes and capped with 100 nm of high-density SiCN from tetramethylsilane. The elemental composition of the thermally annealed film measured by XPS was C 62%, C 12%, Si 25% and O 1%. Different samples were deposited under the same conditions, thermally annealed at 300 °C for 5 minutes, UV annealed at 400 °C for 4 minutes, and then in-situ capped with 100 nm of high-density SiCN using tetramethylsilane. The elemental composition of the film after thermal annealing and UV curing measured by XPS was C 36%, N 20%, Si 38% and O 6%, indicating the presence of carbon loss in the film associated with UV curing.

[0057] Example 3: Deposition of a fluidic silicon carbonitride film using triethylsilane (3ES) and ammonia for SEM For the deposition of the flowable SiNC film by the remote plasma source (RPS), triethylsilane (3ES) was used. 3ES was delivered through a showerhead that bypassed the remote microwave. The liquid flow rate was 2500 mg / min, and 200 sccm of helium was added as the carrier gas for DLI delivery. A mixture of 100 sccm of helium and 500 sccm of ammonia was flowed through the microwave applicator, and the pressure was 0.7 torr. The substrate temperature was 40 °C. The microwave power was 2000 W. The as-deposited film was thermally annealed at 300 °C for 5 minutes. The thickness and refractive index of the as-deposited film were 1675.8 nm and 1.431, respectively. After thermal annealing, the thickness and refractive index were 1249.9 nm and 1.423, respectively, indicating a slight loss of some volatile oligomers at high temperature. The elemental composition of the thermally annealed film measured by XPS was C 30.6%, O 40.0%, and Si 29.4%. The dielectric constant of the film after thermal annealing was 3.50, which may be due to some water absorption caused by dangling bonds. After UV curing, the thickness and refractive index were 968.3 nm and 1.349, respectively, indicating that the film was modified by UV curing and some porosity was introduced. The elemental composition of the film after thermal annealing and UV curing measured by XPS was C 21.6%, O 45.4%, and Si 33.0%, indicating the presence of carbon loss in the film associated with UV curing. The dielectric constant of the UV-cured film was 2.56. Cross-sectional SEM showed that excellent gap filling was achieved on the patterned wafer. Figure 1 is a cross-sectional SEM image of an OSG film showing excellent gap filling for the thermally annealed sample.

[0058] In the provided example, since there is no nitrogen in the alkylhydridosilane, the nitrogen observed in the deposited film is predicted to be derived from ammonia. Thus, if oxygen-containing active species were utilized, it would be expected that oxygen would be incorporated into the deposited film. Alternatively, if hydrogen were used as the active gas, it would be predicted that the deposited film would also contain some hydrogen and would consist of silicon and carbon.

[0059] Although some principles of the present invention have been described in connection with aspects or embodiments, it should be clearly understood that this description is made as merely an example and not as limiting the scope of the present invention.

Claims

Claim 1 A method of depositing a silicon-containing film during a flowing chemical vapor deposition process, comprising: placing a substrate including surface features in a reactor at one or more temperatures within the range of -20 °C to 200 °C; and Formula R ｎ SiH ４－ｎ A step of introducing a precursor compound having into the reactor, wherein R in the formula is a linear or branched C ２ -C ６ alkyl or C ６ -C １０ independently selected from aryl groups, and n is 3; providing a plasma source in the reactor, wherein the compound is at least partially reacted to form a flowing liquid or oligomer, wherein the flowing liquid or oligomer at least partially fills a portion of the surface features to form a first film. A method comprising the above steps. Claim 2 The method according to claim 1, wherein the plasma source in the providing step comprises at least one plasma source selected from the group consisting of a nitrogen plasma, a plasma containing nitrogen and hydrogen, a plasma containing nitrogen and helium, a plasma containing nitrogen and argon, an ammonia plasma, a plasma containing ammonia and helium, a plasma containing ammonia and argon, a plasma containing ammonia and nitrogen, an organic amine plasma, and combinations thereof. Claim 3 The method according to claim 1, wherein the plasma source in the providing step comprises at least one plasma source selected from the group consisting of a carbon source plasma, a hydrocarbon plasma, a plasma containing hydrocarbon and helium, a plasma containing hydrocarbon and argon, a carbon dioxide plasma, a carbon monoxide plasma, a plasma containing hydrocarbon and hydrogen, a plasma containing hydrocarbon and a nitrogen source, a plasma containing hydrocarbon and an oxygen source, and combinations thereof. Claim 4 The method according to claim 1, wherein the plasma source in the providing step comprises at least one plasma source selected from the group consisting of a hydrogen plasma, a helium plasma, an argon plasma, a xenon plasma, and combinations thereof. Claim 5 The plasma source in the step of providing is at least one plasma source selected from the group consisting of water (H ２ O) plasma, oxygen plasma, ozone (O ３ ) plasma, NO plasma, N ２ O plasma, carbon monoxide (CO) plasma, carbon dioxide (CO ２ ) plasma, and combinations thereof, according to the method of claim 1. Claim 6 The method according to claim 1, further comprising heat-treating at one or more temperatures within the range of 100 °C to 1000 °C to densify the first film. Claim 7 The method according to claim 6, further comprising exposing the densified first film to at least one further treatment selected from the group consisting of a plasma, infrared light, a chemical treatment, an electron beam, and UV light to further densify the densified first film. Claim 8 The method according to claim 1, wherein the plasma source is generated in situ. **Claim 9** The method according to claim 1, wherein the plasma source is generated remotely. **Claim 10** The method according to claim 1, wherein the pressure of the reactor is maintained at 100 Torr or less. **Claim 11** The method according to claim 1, wherein the silicon-containing film is selected from the group consisting of silicon carbide, silicon oxide, carbon-doped silicon nitride, carbon-doped silicon oxide, and carbon-doped oxynitride films. **Claim 12** The method according to claim 1, wherein the precursor compound is selected from the group consisting of triethylsilane, isopropyldiethylsilane, phenyldiethylsilane, and benzyldiethylsilane. **Claim 13** The method according to claim 1, wherein the precursor compound is triethylsilane.

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