Forming siCN thin films

Abstract

Methods of depositing a silicon-containing film, such as a SiCN film, on a substrate in a reaction space are provided. The methods can include a vapor deposition process utilizing a gas-phase silicon precursor comprising a halogen and a second gas-phase reactant comprising an amine reactant. In some embodiments, an atomic layer deposition (ALD) cycle includes alternating and sequential contacting of the substrate with a silicon precursor comprising a halogen and a second reactant comprising an amine reactant. In some embodiments, a SiCN film is deposited by alternatingly contacting the substrate with a halosilane, such as octachlorotrisilane, and an amine reactant comprising a diamine or triamine.

Description

[0001] Citation of relevant applications

[0002] This application claims priority to U.S. Provisional Application No. 62 / 962,575, filed January 17, 2020, which is incorporated herein by reference in its entirety. Technical Field

[0003] This disclosure generally relates to the field of semiconductor device manufacturing, and more specifically, to the formation of silicon nitride carbon films. Background Technology

[0004] There is an increasing need for dielectric materials with relatively low dielectric constant (k) values ​​and relatively low acid- or base-based wet etching rates. Typically, deposition processes for forming silicon-containing carbonitride (SiCN) films require nitrogen-containing plasma steps. Summary of the Invention

[0005] In one aspect, a method for forming a silicon-containing thin film, such as a Si(C,N) film, is provided. In some embodiments, the method for forming a silicon-containing thin film, such as a SiCN thin film, on a substrate comprises contacting the substrate alternately and sequentially with a silicon precursor containing a halogen and an amine reactant.

[0006] In some embodiments, a silicon-containing thin film is deposited on a substrate in a reaction chamber using an atomic layer deposition (ALD) process, the ALD process comprising at least one deposition cycle in which the substrate is contacted with a halogen-containing fumed silicon precursor and a fumed amine reactant. In some embodiments, two or more deposition cycles are performed sequentially. In some embodiments, the substrate is contacted with the silicon precursor and amine reactant at a temperature of about 200 to about 400°C.

[0007] In some embodiments, the plasma reactants are not used in at least one deposition cycle. That is, the substrate is not in contact with the plasma during the deposition cycle. In some embodiments, plasma is not used during any deposition cycle. In some embodiments, plasma is not used in the deposition process.

[0008] In some embodiments, the silicon reactant has the formula Si n X 2n+2 Where X is a halogen and n is an integer greater than or equal to 1. In some embodiments, the silicon precursor is an alkyl halosilane. In some embodiments, the silicon precursor is octachlorotrisilane, hexachlorodisilane, pentachlorodisilane, silicon tetrachloride, or trichlorosilane. In some embodiments, the silicon precursor is a bridged halosilane, such as octachlorosiloxane or bis(trichlorosilyl)methane. In some embodiments, the silicon precursor comprises two different halogens.

[0009] In some embodiments, the amine reactant has the formula C a N b H c Where a, b, and c are integers. In some embodiments, the amine reactant comprises a diamine, a triamine, a tetraamine, or a pentamine. In some embodiments, the amine reactant comprises ethylenediamine or propyltriamine.

[0010] In some embodiments, after at least one deposition cycle, the substrate is contacted with an oxidizing reactant. In some embodiments, the oxidizing reactant is selected from the group consisting of: O2, O3, H2O3, H2O, oxygen plasma, and oxygen free radicals.

[0011] In some embodiments, the silicon precursor comprises octachlorotrisilane, and the amine reactant comprises ethylenediamine. Attached Figure Description

[0012] Figure 1 This is a process flow diagram of depositing SiCN thin films using atomic layer deposition (ALD) according to some embodiments.

[0013] Figure 2 This is a process flow diagram of depositing SiOCN thin films using the ALD process according to some embodiments. Detailed Implementation

[0014] Silicon-containing thin films, such as SiCN and SiOCN films, have a wide range of applications, including in integrated circuit manufacturing. In some embodiments, the silicon-containing films described herein can be used as, for example, dielectric layers, etch stop layers, sacrificial layers, low-k spacers, anti-reflective layers (ARLs), passivation layers, and for void-filling applications.

[0015] According to some embodiments, various silicon-containing films, precursors, and methods for depositing said films by vapor deposition, such as by atomic layer deposition (ALD). In some embodiments, the film comprises silicon, carbon, and nitrogen, and may be referred to as a Si(C,N) film. In some embodiments, the film comprises silicon, carbon, hydrogen, and nitrogen. In some embodiments, the film is deposited by a process that does not use plasma, free radicals, or excited-state species. In some embodiments, the film is deposited using a non-oxidizing process, i.e., a process that does not use oxidants. In some embodiments, the process does not use oxidants, such as O2, O3, H2O2, H2O, oxygen plasma, or oxygen free radicals.

[0016] In some embodiments, the silicon-containing thin film is not deposited using liquid-phase methods. In some embodiments, the silicon-containing thin film is deposited on a three-dimensional structure, such as on fins forming a FinFET device.

[0017] In some embodiments, a SiCN film is deposited. In some embodiments, a SiOCN film is deposited. In some embodiments, the SiCN film may be deposited and further processed to form a SiOCN film.

[0018] In some embodiments, silicon-containing films, such as films containing silicon, carbon, hydrogen, and nitrogen, are deposited via a molecular layer deposition (MLD) process, which involves contacting a substrate with one or more silicon halides and one or more organic amines. Exemplary reactants are described below. In some embodiments, a cyclic vapor deposition process is used to deposit silicon-containing films, such as SiCN films. For example, an ALD or cyclic CVD process may be used. In some embodiments, the vapor deposition process for forming SiCN films as described herein does not utilize plasma.

[0019] In some embodiments, an ALD process is used to deposit SiCN films. In some embodiments, the ALD process for forming SiCN films as described herein does not utilize plasma. ALD-type processes are based on controlled, typically self-limiting, surface reactions. Gas-phase reactions are typically avoided by alternating and sequentially contacting the substrate with the reactants. Gas-phase reactants are separated from each other in the reaction chamber, for example, by removing excess reactants and / or reactant byproducts between reactant pulses. Reactants can be removed from near the substrate surface by means of purge gases and / or vacuum. In some embodiments, excess reactants and / or reactant byproducts are removed from the reaction space, for example, by purging with an inert gas.

[0020] In some embodiments, the process for forming a silicon-containing thin film, such as a SiCN film, does not utilize oxidizing reactants. For example, in some embodiments, the process for forming a SiCN film does not utilize oxidizing reactants such as O2, O3, H2O2, H2O, oxygen plasma, or oxygen radicals. In some embodiments, the post-deposition treatment step may utilize plasma or other reactive species, such as oxygen plasma, ozone plasma, hydrogen peroxide, or ozone. In some embodiments, the post-deposition treatment plasma step utilizes nitrogen, hydrogen, N2-H2, or argon plasma. In some embodiments, the post-deposition treatment step is used to adjust film properties. In some embodiments, the post-deposition treatment step is performed after one, two, three, or more deposition cycles. In some embodiments, the post-deposition treatment step is performed after depositing a silicon-containing thin film of a specific thickness. In some embodiments, the post-deposition treatment step is performed at one, two, or more intervals during the deposition process.

[0021] In short, in some embodiments of the vapor deposition process, a substrate or workpiece is placed in a reaction chamber and subjected to alternating, repeated surface reactions. In some embodiments, a silicon-containing film, such as a SiCN film, is deposited via a deposition process, such as a cyclic deposition process, wherein the substrate is exposed to a vapor-phase silicon precursor and a vapor-phase second reactant. In some embodiments, the process is a cyclic CVD process. In some embodiments, the SiCN film is formed by repeating a cycle in which the substrate is alternately contacted with the silicon precursor and the second reactant. In some embodiments, the cycle is an ALD cycle in which the substrate is alternately and sequentially contacted with the silicon precursor and the second reactant. As discussed below, in some embodiments, the silicon precursor is a silicon halide, and the second reactant comprises an amine. In some embodiments, the second reactant is not NH3.

[0022] In some embodiments, for forming a silicon-containing film, such as a SiCN film, each deposition cycle comprises at least two distinct stages. The contact of the reactants with the substrate and their removal from the substrate can be considered as one stage. In some embodiments, additional stages may be added to achieve the desired composition. Reaction conditions, such as temperature, reactants, pressure, etc., can be adjusted to produce a film with the desired characteristics.

[0023] In the first stage, a gaseous first reactant containing a silicon precursor, such as silicon halide, is contacted with a substrate, and no more than about one monolayer of silicon species is formed on the substrate surface. In some embodiments, the silicon reactant contains silicon atoms bonded to one or more halogen atoms and can be bridged by atoms or atomic chains, such as carbon, hydrogen, oxygen, and / or nitrogen atoms. This reactant is also referred to herein as a "silicon precursor," "silicon-containing precursor," or "silicon reactant." This stage may be referred to as the "silicon stage."

[0024] In some embodiments, the silicon precursor is a bis(trichlorosilyl)alkane, a bis(tribromosilyl)alkane, or a bis(triiodosilyl)alkane, such as bis(trichlorosilyl)methane, bis(trichlorosilyl)ethane, bis(triiodosilyl)ethane, and bis(trichlorosilyl)benzene. In some embodiments, the silicon precursor is octachlorotrisiloxane or hexachlorodisiloxane.

[0025] In some embodiments, the silicon precursor may have the general formula X a Y 3-a -Si-R(Ar)-Si-X b Y 3-bIn this context, 'X' is a halogen group, such as fluorine, chlorine, bromine, or iodine, and 'Y' can be hydrogen, alkyl, or alkoxy, and a and b are integers greater than or equal to one, and 'R' can be a substituted or unsubstituted, saturated or unsaturated, branched or straight-chain alkyl chain, and 'Ar' is a substituted or unsubstituted aromatic group, such as benzene, methylbenzene, or nitrobenzene. In some embodiments, the alkyl or aryl bridge may contain carbon atoms, for example, greater than or equal to 1, greater than or equal to 3, or up to 10 carbon atoms. It should be understood that any alkyl or aryl group may contain hydrogen not explicitly described herein. In some embodiments, the silicon precursor may have more than two silicon atoms bridged by alkyl or aromatic groups.

[0026] In some embodiments, the silicon precursor comprises a silane having at least one halogen. In some embodiments, the silicon precursor is a linear, branched, or cyclic halosilane. In some embodiments, the silicon precursor may have the following general formula:

[0027] Si n X 2n+2 or Si n X 2n+2-c L c

[0028] Where n and c are integers greater than or equal to 1, L is a ligand, and X is a halogen. In some embodiments, X can be Cl, F, Br, or I. In some embodiments, L can be hydrogen, alkyl, such as methyl or alkoxy. In some embodiments, the silicon precursor contains two or more different halogen groups.

[0029] In some embodiments, the silicon precursor is a carbon-substituted halosilane, such as an alkyl halosilane. In some embodiments, the silicon precursor is an alkyl-bridged halosilane.

[0030] In some embodiments, the silicon precursor may be, for example, octachlorotrisilane (OCTS), hexachlorodisilane (HCDS), alkyl-substituted halosilanes such as methylpentachlorodisilane, dimethylhexachlorotrisilane, silicon tetrachloride, dichlorosilane, diiodosilane, silicon tetraiodide (SiI4), pentachlorodisilane, or trichlorosilane.

[0031] In the second stage, a second reactant comprising an amine reactant is brought into contact with a substrate. This stage may be referred to as the "amine stage," and the reactant may be referred to as the "amine reactant." In some embodiments, the amine is a diamine or a triamine. In some embodiments, the amine has the formula C a N b H cWhere a, b, and c are integers and greater than or equal to 1. In some embodiments, b is greater than or equal to 2. In some embodiments, the amine may contain saturated or unsaturated ligands, such as saturated or unsaturated alkyl or aryl groups. In some embodiments, the amine may be an aromatic amine, such as an aromatic diamine, triamine, tetraamine, or even a pentaamine. In some embodiments, the organic amine is tetraethylenepentamine, triethylenetetraamine, ethylenediamine, or diethylenetriamine. In some embodiments, the amine may have the formula NH2-R-NH2, where R is a saturated or unsaturated alkyl or aryl group; or NH2-Ar-NH2, where Ar represents an aromatic group. In some embodiments, the second reactant contains ethylenediamine. In some embodiments, the second reactant contains propyltriamine. In some embodiments, the amine reactant may contain up to 20 carbon atoms, less than 15 carbon atoms, less than 10 carbon atoms, or up to 6 carbon atoms. In some embodiments, the amine reactant may contain up to 10 nitrogen atoms, less than 6 carbon atoms, or 1-5 nitrogen atoms. Any alkyl or aryl group in the organic amine may contain hydrogen atoms not explicitly described herein.

[0032] In some embodiments, one or more deposition cycles may be performed at process temperatures below about 600°C, below about 500°C, or below about 450°C. In some embodiments, the deposition temperature is about 150°C to about 450°C, or about 200°C to about 350°C. In some embodiments, the deposition cycle is performed at a process temperature below or equal to about 350°C. In some embodiments, the deposition cycle may be performed at a process temperature of about 100°C or higher. The deposition temperature can be adjusted to obtain a film having the desired composition and characteristics. For example, the temperature can be adjusted to achieve the desired N and / or C concentration in the film.

[0033] In some embodiments, the substrate is not in contact with reactive species generated by plasma during one or more deposition cycles. In some embodiments, the substrate is not in contact with reactive species generated by plasma during any deposition cycle.

[0034] Additional stages can be added, and stages can be removed as needed to adjust the composition of the final film. For example, an oxidation stage may be included in one or more deposition cycles, or after multiple deposition cycles, to form SiOCN. In some embodiments, oxidants such as air, O2, O3, H2O3, H2O, oxygen plasma, or oxygen radicals may be used.

[0035] In some embodiments, one or more stages may be repeated two or more times in a single deposition cycle. For example, in some embodiments, the deposition process may include contacting the substrate with the first reactant two or more times before contacting the substrate with the second reactant.

[0036] In some embodiments, one or more different deposition cycles are provided in the deposition process.

[0037] One or more of the silicon precursor and the second reactant can be provided by means of a carrier gas, such as Ar or He. In some embodiments, the silicon precursor and the second reactant are provided by means of a carrier gas.

[0038] In some embodiments, optional or supplementary steps include exposing the substrate to one or more heterocyclic compounds containing carbon, nitrogen, sulfur, oxygen, or hydrogen atoms. In some embodiments, the heterocyclic compound is pyridine, alkyl-substituted pyridine, pyrrole, imidazole, triazole, thiophene, etc. In some embodiments, the heterocyclic compound is continuously or intermittently flowed into the reaction chamber throughout the deposition process. In some embodiments, the heterocyclic compound flows as a post-deposition process. One or more heterocyclic compounds may be included in a purging step, in which one or more reactants or reaction byproducts are removed from the substrate. For example, in some embodiments, supplementary or optional steps include a purging step in which the substrate is exposed to a purging gas. In some embodiments, supplementary steps are performed in addition to a nitrogen (N2) or argon purging step. In some embodiments, the purging step includes exposing the substrate to a non-reactive gas, such as diatomic nitrogen or argon; and a heterocyclic compound, such as pyridine, alkyl-substituted pyridine, pyrrole, imidazole, pyrimidine, thiophene, etc.

[0039] In some embodiments, two or more stages may overlap or be combined. For example, the silicon precursor and amine reactant may be contacted with the substrate simultaneously in partially or fully overlapping stages. Additionally, although referred to as first and second stages and first and second reactants, the numbering does not necessarily specify the order of the stages or the order in which the substrate is contacted with the reactants. That is, the order of the stages may be varied. Each ALD cycle may begin at either stage. In some embodiments, the deposition cycle may begin by contacting the substrate with the silicon precursor, followed by contacting the substrate with the amine reactant. In some embodiments, the deposition cycle may begin by contacting the substrate with the amine reactant, followed by contacting the substrate with the silicon precursor. Unless otherwise stated, the reactants may be contacted with the substrate in any order, and the process may begin with either reactant.

[0040] In some embodiments, a third oxidation stage is used to form the SiOCN film. In some embodiments, the oxidation stage is used in each deposition cycle. In some embodiments, the oxidation stage is included only after a certain number of deposition cycles. That is, a deposition cycle including the oxidation stage may be included after a SiCN film of the desired thickness has been formed. In some embodiments, the oxidation stage is not included in any deposition cycle. In some embodiments, after depositing a SiCN film of the desired thickness, an oxidation process is performed to convert SiCN into SiOCN. In embodiments of forming the SiOCN film, the silicon precursor may comprise a silicon reactant containing oxygen, such as a siloxane, such as hexachlorodisiloxane or octachlorotrisiloxane.

[0041] In some embodiments, the substrate to be deposited, such as a semiconductor workpiece, is loaded into a reaction space or reactor. The reactor may be part of a clustering tool, in which various different methods are used in the integrated circuit formation process. In some embodiments, a flow reactor is utilized. In some embodiments, a nozzle-type reactor is utilized. In some embodiments, a space-divided reactor is utilized. In some embodiments, a single-wafer ALD reactor capable of high-volume manufacturing is used. In other embodiments, a batch reactor containing multiple substrates is used. For embodiments using a batch ALD reactor, the number of substrates ranges from 10 to 200, from 50 to 150, or from 100 to 130.

[0042] In some embodiments, the exposed surfaces of the workpiece may be pretreated, if necessary, to provide reactive sites for the first stage of the ALD process. In some embodiments, a separate pretreatment step is not required. In some embodiments, the substrate is pretreated to provide the desired surface termination.

[0043] Between reactant contact phases, excess reactants and reaction byproducts (if any) are removed from the vicinity of the substrate, and particularly from the substrate surface. In some embodiments, excess reactants and reaction byproducts (if any) are removed from the substrate surface, for example, by purging the reaction chamber between reactant contact phases, such as by purging with an inert gas. The flow rate and contact time for each reactant are adjustable, just like the removal steps, thereby allowing control over the quality and various properties of the film. In some embodiments, the substrate can be moved such that it contacts one reactant at a time.

[0044] In some embodiments, a gas is continuously supplied to the reaction chamber during each deposition cycle or throughout the entire ALD process. In some embodiments, the gas may contain an inert gas, such as helium or argon. The flowing gas may serve as a carrier gas for one or more reactants and may also serve as a purge gas.

[0045] In some embodiments, a gas is continuously supplied to the reaction chamber during each deposition cycle or throughout the entire deposition process. In some embodiments, the gas may contain one or more heterocyclic compounds, ammonia, hydrazine, or any alkyl-substituted hydrazine.

[0046] The deposition cycle is repeated until a film with the desired thickness and composition is obtained. In some embodiments, deposition parameters, such as temperature, precursor flow rate, contact time, removal time, and / or the reactants themselves, may be varied in one or more deposition cycles during the ALD process to obtain a film with the desired composition and characteristics.

[0047] In some embodiments, a pulse of reactant is supplied to a reaction space containing a substrate. The term "pulse" can be understood as encompassing a predetermined amount of time during which reactant is supplied to the reaction chamber. The term "pulse" does not limit the length or duration of the pulse, and the pulse can be of any duration. In some embodiments, the substrate is moved to the reaction space containing reactant. In some embodiments, the substrate is subsequently moved from the reaction space containing a first reactant to a second, different reaction space containing a second reactant.

[0048] In some embodiments, if necessary or required, the substrate is contacted with a first silicon halide reactant after initial surface termination. For example, a first silicon reactant pulse may be supplied to a reaction chamber containing the substrate. According to some embodiments, the silicon reactant comprises volatile silane halide species, such as octachlorotrisilane, that are reactive to the substrate surface of interest. Thus, the species of the silicon reactant are adsorbed onto these substrate surfaces. In some embodiments, the first reactant pulse causes the substrate surface to self-saturate, such that any excess component of the first reactant does not further react with the molecular layer of silicon species formed on the substrate during this portion of the deposition cycle.

[0049] Each reactant may be supplied in gaseous form. For the purposes of this specification, a reactant is considered “volatile” if the species exhibits sufficient vapor pressure under process conditions to deliver the species to the reaction chamber at a sufficient concentration to saturate the exposed surface of the substrate.

[0050] In some embodiments, the contact time between the silicon reactant and the substrate surface is approximately 0.05 seconds to approximately 5.0 seconds, approximately 0.1 seconds to approximately 3 seconds, or approximately 0.2 seconds to approximately 1.0 seconds. A skilled technician can easily determine the optimal contact time based on the specific circumstances.

[0051] After approximately one molecular layer of silicon species has had sufficient time to form on the substrate surface, excess first silicon reactant and reaction byproducts (if any) are removed from the substrate surface. In some embodiments, removing excess reactant and reaction byproducts (if any) may include purging the reaction chamber. In some embodiments, the reaction chamber may be purged by: stopping the flow of the first reactant while continuing to flow the carrier gas; or by allowing the purge gas to flow for sufficient time to diffuse or purge excess reactant and reactant byproducts (if any) from the reaction space. In some embodiments, excess first silicon precursor is purged using an inert gas, such as nitrogen or argon, that can flow throughout the deposition cycle. In some embodiments, the substrate may be moved from the reaction space containing the first reactant to a second, different reaction space. In some embodiments, the first reactant is removed for approximately 0.1 seconds to approximately 10 seconds, approximately 0.3 seconds to approximately 5 seconds, or approximately 0.3 seconds to approximately 1 second. Contact with and removal of silicon reactant may be considered as the first stage or silicon stage of the deposition cycle.

[0052] In the second stage, the substrate is contacted with a second reactant comprising an amine, such as a diamine or triamine. The amine reactant may be provided to the substrate in one or more reactant pulses. In some embodiments, the second reactant is provided in two or more distinct pulses, without introducing another reactant between any of the two or more pulses. For example, in some embodiments, the diamine or triamine is provided in two or more consecutive pulses, without introducing a silicon precursor between the consecutive pulses.

[0053] In some embodiments, the second reactant is in contact with the substrate for about 0.1 seconds to about 10 seconds. In some embodiments, the second reactant is in contact with the substrate for about 0.1 seconds to about 10 seconds, about 0.5 seconds to about 5 seconds, or about 0.5 seconds to about 2.0 seconds. However, depending on the reactor type, substrate type, and its surface area, the contact time of the second reactant can even be longer than about 10 seconds. In some embodiments, the contact time can be on the order of minutes.

[0054] After the second reactant has sufficient time to react with the silicon species on the substrate surface, excess second reactant and reaction byproducts (if any) are removed from the substrate surface. In some embodiments, the removal of excess second reactant and reaction byproducts (if any) may include purging the reaction chamber. In some embodiments, the reaction chamber may be purged by: stopping the flow of the second reactant while continuing to flow the carrier gas; or by allowing the purge gas to flow for sufficient time to diffuse or purge excess reactant and reactant byproducts (if any) from the reaction space. In some embodiments, excess second reactant is purged using an inert gas, such as nitrogen or argon, that can flow throughout the deposition cycle. In some embodiments, the substrate may be moved from the reaction space containing the second reactant to a different reaction space. In some embodiments, the second reactant is removed for about 0.1 seconds to about 10 seconds, about 0.3 seconds to about 5 seconds, or about 0.3 seconds to about 1 second. The contact and removal of the second reactant may be considered as a second stage of the deposition cycle.

[0055] The substrate on which the thin film is deposited can contain a variety of materials. In some embodiments, the substrate can contain an integrated circuit artifact. In some embodiments, the substrate can contain silicon. In some embodiments, the substrate can contain silicon oxide, such as a thermal oxide. In some embodiments, the substrate can contain a high-k dielectric material. In some embodiments, the substrate can contain carbon. For example, the substrate can contain an amorphous carbon layer, graphene, and / or carbon nanotubes.

[0056] In some embodiments, the substrate may comprise a metal, including but not limited to W, Cu, Ni, Co, and / or Al. In some embodiments, the substrate may comprise a metal nitride, including but not limited to TiN and / or TaN. In some embodiments, the substrate may comprise a metal carbide, including but not limited to Ti(Al)C, TiC, and / or TaC. In some embodiments, the substrate may comprise a metal chalcogenide, including but not limited to MoS2, Sb2Te3, and / or GeTe. In some embodiments, the substrate may comprise a material that has been oxidized or otherwise damaged by exposure to a reactive oxygen source, such as oxygen plasma.

[0057] In some embodiments, the substrate described herein for use in vapor deposition processes, such as ALD processes, may comprise organic materials. For example, the substrate may comprise organic materials such as plastics, polymers, and / or photoresists. In some embodiments where the substrate comprises organic materials, the reaction temperature of the ALD process may be below about 300°C or below about 200°C. In some embodiments, the reaction temperature may be below about 150°C, below about 100°C, below about 75°C, or below about 50°C.

[0058] In some embodiments where the substrate comprises organic material, the maximum process temperature can be as low as about 100°C. In some embodiments where the substrate comprises organic material, the absence of plasma or oxidants allows for the deposition of SiCN films on organic material, which would otherwise be degraded in deposition processes involving plasma generated by oxygen or other reactive oxygen species.

[0059] According to some embodiments, the pressure in the reaction chamber is maintained at about 0.01 Torr to about 50 Torr, or about 0.1 Torr to about 10 Torr, during processing. In some embodiments, the pressure in the reaction chamber is greater than about 6 Torr or about 20 Torr. In some embodiments, the SiCN deposition process can be carried out at a pressure of about 20 Torr to about 500 Torr, about 20 Torr to about 50 Torr, or about 20 Torr to about 30 Torr.

[0060] In some embodiments, the deposition process of a silicon-containing thin film, such as a SiCN film, may include multiple deposition cycles, wherein at least one deposition cycle is performed in a high-pressure system. For example, a deposition cycle may include alternating and sequentially contacting a substrate with a silicon precursor and a second reactant under high pressure. In some embodiments, one or more deposition cycles may be performed at process pressures of about 6 to about 500 Torr, about 6 to about 100 Torr, or about 6 to about 50 Torr. In some embodiments, one or more deposition cycles may be performed at process pressures greater than about 20 Torr (including about 20 to about 500 Torr, about 30 to about 500 Torr, about 40 to about 500 Torr, or about 50 to about 500 Torr). In some embodiments, one or more deposition cycles may be performed at process pressures of about 20 to about 30 Torr, about 20 to about 100 Torr, about 30 to about 100 Torr, about 40 to about 100 Torr, or about 50 to about 100 Torr.

[0061] In some embodiments, silicon precursors, such as halosilanes reacting with amines, are used in the deposition cycle. See also Figure 1 Furthermore, according to some embodiments, an ALD deposition process 100 is used to deposit a silicon-containing thin film on a substrate in a reaction space, the ALD deposition process comprising one or more deposition cycles, the deposition cycle comprising:

[0062] In step 120, the substrate is brought into contact with a vapor silicon precursor, such as a halosilane, such as octachlorotrisilane, so that silicon species are adsorbed onto the substrate surface.

[0063] In step 140, excess silicon precursors and reaction byproducts (if any) are removed from the substrate surface;

[0064] In step 160, the substrate is contacted with a second reactant containing an amine, such as a diamine or triamine; and

[0065] In step 180, excess amine reactants and reaction byproducts (if any) are removed from the substrate surface.

[0066] The deposition cycle, including steps 120, 140, 160 and 180, can be repeated 190 to form a SiCN film with the desired thickness.

[0067] In some embodiments, the substrate is contacted alternately and sequentially with a silicon precursor and an amine reactant during a deposition cycle. In some embodiments, the substrate is contacted alternately and sequentially with a halosilane and a diamine or triamine. In some embodiments, the substrate is contacted alternately and sequentially with octachlorotrisilane and ethylenediamine.

[0068] To obtain the desired membrane, it can be modified. Figure 1 The temperature of the deposition process is shown. In some embodiments, a temperature of about 200°C to about 400°C is used to form the SiCN film. In some embodiments, the temperature may be about 250°C to about 350°C. The nitrogen and carbon concentrations can be adjusted by regulating the temperature, precursor dosage, and / or purge time.

[0069] In some embodiments, after multiple deposition cycles for forming SiCN, the substrate is contacted with an oxidant to form SiOCN. (Reference) Figure 2 Furthermore, according to some embodiments, a silicon-containing thin film is deposited on a substrate in a reaction space by an ALD deposition process 200 comprising at least one cycle, said at least one cycle comprising:

[0070] In step 210, the substrate is brought into contact with a vapor silicon precursor, such as a halosilane, such as octachlorotrisilane, so that silicon species are adsorbed onto the substrate surface.

[0071] In step 220, excess silicon precursors and reaction byproducts (if any) are removed from the substrate surface;

[0072] In step 230, the substrate is contacted with a second reactant containing an amine, such as a diamine or triamine; and

[0073] In step 240, excess amine reactants and reaction byproducts (if any) are removed from the substrate surface.

[0074] The deposition cycle, including steps 210, 220, 230, and 240, can be repeated more than 250 times to form a SiCN film with the desired thickness. When the desired thickness is reached, the SiCN film can be treated with an oxidant 260 to convert some or all of the deposited SiCN into SiOCN.

[0075] In some embodiments, after the oxidant treatment, further cycles of SiCN deposition and subsequent oxidation 270 are performed. Oxidation can be carried out using oxidants such as air, water, oxygen, ozone, hydrogen peroxide, or oxygen plasma, such as O2 / O3 plasma.

[0076] SiCN membrane characteristics

[0077] Silicon-containing thin films, such as SiCN films, deposited according to some embodiments discussed herein can achieve impurity levels or concentrations of one or more impurities below about 3 at%, below about 1 at%, below about 0.5 at%, or below about 0.1 at%. In some films, the total impurity level excluding hydrogen can be below about 5 at%, below about 2 at%, below about 1 at%, or below about 0.2 at%. And in some films, the hydrogen level can be below about 30 at%, below about 20 at%, below about 15 at%, or below about 10 at%. As used herein, with respect to SiCN films, impurities can be considered any element other than Si, C, and / or N.

[0078] According to some embodiments, silicon-containing thin films, such as SiCN thin films, can exhibit step coverage greater than about 50%, greater than about 80%, greater than about 90%, or greater than about 95%. In some cases, the step coverage can be greater than about 98%, and in some cases, about 100% (within the accuracy of the measuring tool or method). In some embodiments, the step coverage and pattern loading effect can be greater than about 100%, greater than about 110%, greater than about 120%, greater than about 130%, or greater than about 140%. These values ​​can be achieved in features having an aspect ratio of about 2 or greater, in some embodiments a feature having an aspect ratio of about 3 or greater; in some embodiments a feature having an aspect ratio of about 5 or greater; and in some embodiments a feature having an aspect ratio of about 8 or greater.

[0079] In some embodiments, the tiered coverage may be between about 50% and about 110%, between about 80% and about 110%, between about 90% and about 110%, between about 95% and about 110%, between about 98% and about 110%, or between about 100% and about 110%. In some embodiments, the tiered coverage may be between about 50% and about 100%, between about 80% and about 100%, between about 90% and about 100%, between about 95% and about 100%, or between about 98% and 100%.

[0080] In some embodiments, the membrane growth rate is approximately To date In some embodiments, the membrane growth rate is greater than approximately Greater than approximately Greater than approximately Greater than approximately Greater than approximately Greater than approximately Greater than approximately or even greater than approximately

[0081] In some embodiments, silicon-containing thin films, such as SiCN films, are deposited to thicknesses of about 3 nm to about 50 nm, about 5 nm to about 30 nm, and about 5 nm to about 20 nm. Feature dimensions (widths) of these thicknesses can be below about 100 nm, below about 50 nm, below about 30 nm, below about 20 nm, and in some cases below about 15 nm. According to some embodiments, SiCN films are deposited on three-dimensional structures, and the thickness at the sidewalls can be slightly or even greater than about 10 nm. In some embodiments, silicon-containing thin films, such as SiCN films, can be deposited to thicknesses greater than about 50 nm. In some embodiments, silicon-containing thin films, such as SiCN films, can be deposited to thicknesses greater than about 100 nm. In some embodiments, silicon-containing thin films, such as SiCN films, are deposited to thicknesses greater than about 1 nm, greater than about 2 nm, greater than about 3 nm, greater than about 5 nm, and greater than about 10 nm.

[0082] According to some embodiments, silicon-containing thin films, such as SiCN films, can be deposited with various wet etch rates (WER). In some embodiments, when using blanket-coated WER at 0.5% dHF (nm / min), the SiCN film may have a WER value of less than about 50 nm / min. In some embodiments, the SiCN film may have a WER value of greater than about 30 nm / min in 0.5% dHF.

[0083] In some embodiments, the k value is less than about 10, less than about 7, or less than about 5. In some embodiments, the nitrogen content is less than about 40 at%, or less than about 30 at%, or less than about 25 at%, or less than about 15 at%, or less than about 10 at%, or less than about 5 at%, and the carbon content is less than about 40 at%, less than about 30 at%, less than about 25 at%, less than about 15 at%, less than about 10 at%, or less than about 5 at%.

[0084] For simplicity, unless otherwise indicated, all atomic percentage (i.e., at%) values ​​provided herein do not include hydrogen, as it is difficult to analyze hydrogen accurately in a quantitative manner. However, in some embodiments, where it is possible to analyze hydrogen with reasonable precision, the hydrogen content of the membrane is less than about 20 at%, less than about 10 at%, or less than about 5 at%.

[0085] In some embodiments, the deposited silicon-containing thin film, such as a SiCN thin film, may contain up to about 40% carbon on an atomic basis (at%). In some embodiments, the deposited silicon-containing thin film, such as a SiCN thin film, may contain up to about 50% silicon on an atomic basis (at%). In some embodiments, the silicon-containing thin film, such as a SiCN film, may contain about 10% to about 50%, about 15% to about 40%, or about 20% to about 35% silicon on an atomic basis. In some embodiments, the silicon-containing thin film, such as a SiCN film, may contain at least about 15%, about 20%, about 25%, or about 30% silicon on an atomic basis.

[0086] In some embodiments, the silicon-containing thin film, such as a SiCN film, is a continuous film. In some embodiments, the k-value of the SiCN film is less than about 10. In some embodiments, the k-value of the SiCN film is less than about 5. For example, in some embodiments, the k-value of a SiCN film deposited at a temperature of about 200°C to about 400°C may be less than about 5. In some embodiments, the k-value of the SiCN film is from about 4 to about 10.

[0087] In some embodiments, the silicon-containing thin films deposited according to this disclosure, such as SiCN films, do not contain laminate or nanolaminate structures.

[0088] For simplicity, the terms “membrane” and “thin film” are used herein. “Membrane” and “thin film” refer to any continuous or discontinuous structure and material deposited by the methods disclosed herein. For example, “membrane” and “thin film” can include 2D materials, nanorods, nanotubes, or nanoparticles, or even single, partial, or complete molecular layers or partial or complete atomic layers or atomic and / or molecular clusters. “Membrane” and “thin film” may contain materials or layers with pores, but are still at least partially continuous.

[0089] Those skilled in the art will understand that numerous and varied modifications can be made without departing from the spirit of the invention. The described features, structures, characteristics, and precursors can be combined in any suitable manner. Therefore, it should be clearly understood that the form of the invention is merely illustrative and is not intended to limit the scope of the invention. It is intended that all modifications and variations fall within the scope of the invention as defined in the appended claims.

Claims

1. A method for forming a SiCN thin film on a substrate in a reaction space by an atomic layer deposition (ALD) process comprising at least one deposition cycle, said at least one deposition cycle comprising alternating and sequentially: Contact the substrate with a halogen-containing fumed silicon precursor; and contacting the substrate with an amine reactant having the formula C a N b H c where a, b, and c are integers, and b is greater than or equal to 2, wherein no plasma reactant is utilized in the deposition cycle.

2. The method of claim 1, wherein the silicon precursor has the formula Si n X 2n+2 , where X is a halogen and n is an integer greater than or equal to 1.

3. The method of claim 1, wherein the silicon precursor comprises an alkyl halosilane.

4. The method according to claim 1, wherein the silicon precursor comprises octachlorotrisilane, hexachlorodisilane, pentachlorodisilane, silicon tetrachloride, or trichlorosilane.

5. The method according to claim 1, wherein the amine reactant comprises a diamine or a triamine.

6. The method according to claim 1, wherein the amine reactant comprises ethylenediamine or propyltriamine.

7. The method of claim 1, wherein the silicon precursor comprises a bridged halosilane.

8. The method of claim 7, wherein the silicon precursor comprises octachlorosiloxane or bis(trichlorosilyl)methane.

9. The method of claim 1, further comprising contacting the substrate with an oxidizing reactant after at least one deposition cycle.

10. The method according to claim 9, wherein the oxidizing reactant is selected from the group consisting of: O2, O3, H2O2, H2O, oxygen plasma, and oxygen free radicals.

11. A method for forming a SiCN thin film on a substrate, comprising contacting the substrate alternately and sequentially with a silicon precursor comprising a halogen and an amine reactant via an ALD process, wherein the silicon precursor comprises octachlorotrisilane, pentachlorodisil, hexachlorodisil, or trichlorosilane, wherein the amine reactant comprises a diamine or a triamine, wherein a plasma reactant is not used in the ALD process.

12. The method of claim 11, wherein the substrate is in contact with the silicon precursor and the amine reactant at a temperature of 200 to 400°C.

13. The method of claim 11, wherein the amine reactant comprises ethylenediamine or propyltriamine.

14. The method of claim 11, wherein the silicon precursor comprises octachlorotrisilane, and the amine reactant comprises ethylenediamine.

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