Precursor for forming silicon-containing thin film having high hardness and low dielectric constant, and method for manufacturing silicon-containing thin film using same

Abstract

According to one embodiment of the present disclosure, a precursor for forming a silicon-containing thin film is a compound represented by the following Chemical Formula 1 or 2: wherein in Chemical Formula 1 and 2, A is a cycloalkyl group having 4 to 7 carbon atoms, R1, R4, and R5 are each independently selected from hydrogen, and a substituted or unsubstituted alkyl group having 1 to 3 carbon atoms; and R2, R3 and R6 are each independently an alkyl group having 1 or 2 carbon atoms. Accordingly, a silicon-containing thin film having high hardness and low dielectric constant characteristics can be provided using a silicon precursor having an asymmetric structure including a cycloalkyl group.

Description

Cross - reference to related applications This application claims the priority of Korean Patent Application No. 10 - 2023 - 0182236, filed on December 14, 2023, with the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference. Technical field

[0001] The present invention relates to a precursor for forming a silicon - containing thin film and a method for manufacturing a silicon - containing thin film using the precursor, and more particularly, to a silicon - containing thin film having high hardness and low dielectric constant characteristics and a method for manufacturing the same. Background art

[0002] With the development of electronic technology, the demand for miniaturization and light weight of semiconductor devices used in various electronic devices is rapidly increasing. Various physical and chemical deposition methods have been proposed to form fine semiconductor devices, and various studies have been conducted to form metal - containing thin films, dielectric thin films, etc. using these deposition methods.

[0003] Meanwhile, silicon dioxide (SiO2) or silicon oxyfluoride (SiOF), which is mainly used as an inter - layer insulating film in semiconductor device manufacturing, has problems such as high capacitance and resistance - capacitance delay (RC delay) when manufacturing ultra - high - density circuits of 0.5 μm or less. Therefore, in order to reduce the RC delay of multi - layer metal films used in semiconductor device integrated circuits, recently, active research has been conducted to form an inter - layer insulating film used in metal wiring with a material having a low dielectric constant (relative dielectric constant k≤3.0). These low - dielectric - constant thin films are formed of inorganic materials such as SiCOH films mixed with Si, O, C, and H and doped fluorine amorphous carbon (a - C:F) films, or formed of organic materials containing carbon (C).

[0004] These silicon - based thin films with low dielectric constants can be formed by spin - on dielectric (SOD) films or chemical vapor deposition (CVD) processes. SOD films refer to insulating films formed by coating a silicon precursor using a spin - coating method and then converting the precursor into a silicon oxide film by heat treatment (e.g., at 300 °C to 600 °C). In the case of such formed insulating films, there are problems such as poor thermal stability due to a relatively low heat - resistant limit temperature (about 450 °C or lower), volume shrinkage occurring after heat treatment, and low mechanical strength. In addition, there are also problems such as poor adhesion to upper and lower wiring materials, high stress caused by thermal curing, and dielectric constant changes due to environmental moisture adsorption, which reduce the reliability of the device.

[0005] In the CVD process, a thin film can be formed by a thermally induced chemical reaction between a precursor and a reaction gas on the surface of a substrate. Therefore, the deposition process is carried out under high - temperature conditions, in which case there is a problem that the structure of the device having a layer formed on the substrate is damaged due to the high temperature.

[0006] To solve these problems, plasma enhanced chemical vapor deposition (PECVD) has been proposed to deposit metal and dielectric films at relatively low temperatures.

[0007] In the PECVD process, radio frequency (RF) energy is applied to the reaction zone to promote the excitation and / or dissociation of the reaction gases, thereby generating highly reactive plasma species. Due to the high reactivity of the plasma generated in this way, the energy required to initiate the chemical reaction is reduced. Therefore, in the PECVD process, the temperature required to form the film-forming material can be reduced. Due to the introduction of these devices and methods, the structural dimensions of semiconductor devices have been significantly reduced. SUMMARY OF THE INVENTION

[0008] Silicon precursors for forming conventional silicon films with a low dielectric constant include octamethylcyclotetrasiloxane (OMCTS), diethoxymethylsilane (DEMS), tetraethoxysilicate (TEOS), etc. These precursors exist in a liquid state at room temperature, making the process easy, but they have the disadvantage of low hardness due to the formation of large non-uniformly distributed pores within the film. As a result, the mechanical strength of the film is insufficient, which causes various difficulties in the manufacture of semiconductor devices and limits the scope of applications.

[0009] Accordingly, an object of the present disclosure is to provide a film having high hardness and a low dielectric constant and excellent mechanical strength while having a low dielectric coefficient, and a method for manufacturing the same.

[0010] The object of the present disclosure is not limited to the above object, and other objects not mentioned above will be apparent to those skilled in the art from the following description.

[0011] According to an embodiment of the present disclosure, a precursor for forming a silicon-containing film is represented by the following Chemical Formula 1 or 2.

[0012] [Chemical Formula 1] [Chemical Formula 2]

[0013] In Chemical Formulas 1 and 2, A is a cycloalkyl group having 4 to 7 carbon atoms, and R1, R4, and R5 are each independently selected from hydrogen and a substituted or unsubstituted alkyl group having 1 to 3 carbon atoms; R2, R3, and R6 are each independently an alkyl group having 1 or 2 carbon atoms.

[0014] A silicon-containing film according to an embodiment of the present disclosure is manufactured by depositing the precursor.

[0015] A method for manufacturing a silicon-containing film according to an embodiment of the present disclosure includes depositing a silicon precursor represented by the above Chemical Formula 1 or 2 on a substrate by plasma enhanced chemical vapor deposition (PECVD).

[0016] Details of other embodiments will be included in the detailed description and drawings of the present invention.

[0017] According to this embodiment of the present disclosure, the silicon precursor represented by Chemical Formula 1 or 2 is a silicon compound having an asymmetric structure containing a cycloalkyl group, and when the silicon precursor is used to form a silicon thin film, a thin film having high hardness and low dielectric constant can be provided, and the thin film has excellent mechanical strength while having a low dielectric constant. In addition, by using a single silicon precursor, a silicon-containing thin film having high hardness and low dielectric constant can be formed without separately supplying materials such as a pore-forming agent.

[0018] In addition, the silicon compound having an asymmetric structure containing a cycloalkyl group according to an embodiment of the present disclosure has a high vapor pressure at a low process temperature, so that the reaction gas can be stably supplied to the substrate surface during the thin film deposition process.

[0019] In addition, when energy is applied during the thin film formation process, the silicon precursor according to an embodiment of the present disclosure can be easily decomposed, so it has the advantages of being able to form a thin film with low dielectric constant characteristics and easily controlling the bonding ratio of Si-CH3 in the thin film.

[0020] The effects of the present disclosure are not limited to the above effects, and through the following description, those of ordinary skill in the art will clearly understand other effects not mentioned above.

[0021] The above objects to be achieved by the present disclosure, the means for achieving the objects, and the effects of the present disclosure do not specifically describe the essential features of the claims. Therefore, the scope of the claims is not limited to the content of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The above and other aspects, features, and other advantages of the present disclosure will be more clearly understood by combining the following detailed description with the accompanying drawings, in which: Figure 1 Shows the H-NMR analysis results of the silicon precursor manufactured according to Example 1; Figure 2 Shows the H-NMR analysis results of the silicon precursor manufactured according to Example 2; Figure 3 Shows the thermogravimetric analysis results of the silicon precursor manufactured according to Example 1; and Figure 4 Shows the thermogravimetric analysis results of the silicon precursor manufactured according to Example 2. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0023] Advantages and features of the present disclosure and a method of realizing the present disclosure will be more clearly understood from embodiments described below in detail with reference to the accompanying drawings. However, the present disclosure is not limited to the following embodiments, but may be implemented in various different forms. The embodiments are provided only to complete the disclosure of the present application and to provide a complete content of the category of the present invention to those of ordinary skill in the art to which the present disclosure pertains.

[0024] When describing the present disclosure, if it is determined that related known technologies unnecessarily obscure the gist of the present disclosure, detailed descriptions of these technologies will be omitted. Terms such as "comprising", "having", and "consisting of" used herein generally intend to allow the addition of other components, unless these terms are used together with the word "only". When a component is expressed in the singular form, the singular form may include the plural form unless otherwise clearly stated.

[0025] Even if not explicitly stated, ingredients are interpreted to include ordinary error ranges.

[0026] According to an embodiment of the present disclosure, a silicon precursor for forming a silicon-containing thin film may be represented by the following Chemical Formula 1 or 2.

[0027] [Chemical Formula 1] [Chemical Formula 2]

[0028] R1 in Chemical Formula 1 and R4 and R5 in Chemical Formula 2 may each independently be selected from hydrogen and an alkyl group having 1 to 3 carbon atoms. For example, R1 in Chemical Formula 1 and R4 and R5 in Chemical Formula 2 may each independently be selected from methyl and ethyl. Preferably, for example, R1 in Chemical Formula 1 and R4 and R5 in Chemical Formula 2 may each be methyl. In this case, a thin film with a high deposition rate can be formed, and at the same time, due to the low vapor pressure, the deposition process is easy.

[0029] For example, an alkyl group having 1 to 3 carbon atoms may be substituted with one or more substituents such as an amino group, a hydroxyl group, a cyano group, a halogen, a nitro group, and an alkoxy group, but is not limited thereto.

[0030] R2 and R3 in Chemical Formula 1 and R6 in Chemical Formula 2 may each independently be an alkyl group having 1 or 2 carbon atoms. For example, R2 and R3 in Chemical Formula 1 and R6 in Chemical Formula 2 may each be methyl. In this case, a thin film with a high deposition rate can be formed, and at the same time, due to the low vapor pressure, the deposition process is easy.

[0031] In Chemical Formulas 1 and 2, A is a cycloalkyl group having 4 to 7 carbon atoms. A cycloalkyl group is a functional group having a cyclic saturated hydrocarbon structure, which forms nanopores in a thin film during the thin film deposition process, thereby providing a silicon-containing thin film having excellent hardness and low dielectric constant characteristics. In addition, the cyclic saturated hydrocarbon may include a plurality of C-Hx bond structures to provide a thin film having excellent mechanical strength and elasticity.

[0032] Optionally, if desired, the cycloalkyl group having 4 to 7 carbon atoms may further include a substituent. For example, the cycloalkyl group having 4 to 7 carbon atoms may be substituted with one or more substituents selected from an alkyl group having 1 to 6 carbon atoms, an amino group, a hydroxyl group, a cyano group, a halogen, a nitro group, and an alkoxy group, but is not limited thereto.

[0033] For example, in Chemical Formulas 1 and 2, A may each independently be selected from a cyclopentyl group and a cyclohexyl group. In this case, the silicon thin film formed from the silicon precursor represented by Chemical Formula 1 or 2 has the advantages of being thermally stable, having a low dielectric constant, and having excellent hardness.

[0034] For example, the precursor for forming the silicon thin film may be selected from cyclopentyl diethoxymethylsilane, cyclopentyl dimethylethoxysilane, cyclohexyl dimethoxymethylsilane, and cyclohexyl dimethylmethoxysilane. In this case, the thin film formed during the deposition process has good hardness and also has a low dielectric constant that can be used for various devices.

[0035] Specifically, for example, the silicon precursor may be selected from the compounds represented by the following Chemical Formulas 3 and 4.

[0036]

[0037] The silicon precursors according to Chemical Formulas 3 and 4 have an asymmetric structure in which a bulky cyclopentyl or cyclohexyl group, a methoxy group, and a methyl group are bonded to Si. Therefore, during the deposition process, nanopores are effectively formed on the substrate. The thin film formed in this way is thermally stable, has nanopores formed by a bulky cyclopentyl or cyclohexyl group, and has low dielectric constant characteristics. Therefore, due to excellent mechanical strength, high hardness, and low dielectric properties, the thin film has the advantage of being suitable for semiconductor devices. In addition, even when the power is increased, the thin film formed from the silicon precursor of the present disclosure can maintain effective low dielectric properties.

[0038] According to the present disclosure, when manufacturing a silicon-containing thin film, a silicon-containing thin film having high hardness and a low dielectric constant may be formed only using the silicon precursors of Chemical Formulas 1 and / or 2 without adding auxiliary materials such as a pore-forming agent compound. Specifically, since the silicon precursors of Chemical Formulas 1 and 2 according to the present disclosure contain a cycloalkyl group, nanopores can be formed in the thin film without using a compound such as a pore-forming agent other than the silicon precursor.

[0039] In addition, the silicon precursor of the present disclosure is a single molecule with an asymmetric structure, containing one silicon atom in one molecule and having a low vapor pressure. Therefore, a thin film can be formed at a high deposition rate during the deposition process. Thus, a silicon thin film with a lower dielectric constant can be formed while meeting the mechanical strength required in the semiconductor process.

[0040] In addition, it has the advantage that the carbon content in the silicon-containing thin film can be easily controlled as needed, so that a thin film with a desired dielectric constant can be easily manufactured while improving the mechanical strength.

[0041] In addition, due to the thermal stability and extremely low-level low dielectric constant characteristics, the thin film formed using the silicon precursors of Chemical Formulas 1 and 2 according to the present disclosure is applicable to the semiconductor device manufacturing process. In addition, a thin film with a low dielectric constant can be provided for use to replace the dielectric layer used in the metal multi-layer wiring of traditional semiconductor devices. In this case, the performance of the device can be improved by improving the resistance-capacitance signal delay that increases with the miniaturization and integration of the metal multi-layer wiring.

[0042] As described above, the silicon precursor according to the present disclosure contains one silicon atom in one molecule. Therefore, the silicon precursor has the characteristic of low vapor pressure. For example, the vapor pressure of the silicon precursors represented by Chemical Formulas 1 and 2 at 25 °C can be 0.03 mmHg to 0.2 mmHg.

[0043] Therefore, due to the low vapor pressure characteristic of the silicon precursor, when forming a thin film by a plasma-enhanced chemical vapor deposition (PECVD) process, the silicon precursors of Chemical Formulas 1 and 2 can be easily supplied to the reactor in a gaseous form. Specifically, the silicon precursors of Chemical Formulas 1 and 2 of the present disclosure can be advantageously used for supplying the precursor to the reactor using a bubbling tank. In addition, a silicon-containing thin film with an excellent deposition rate can be provided.

[0044] In addition, the silicon precursors of Chemical Formulas 1 and 2 include a cyclic saturated hydrocarbon structure, which can provide a thin film with excellent mechanical strength and improved elasticity by containing a large amount of C-Hx structures.

[0045] The precursors of Chemical Formulas 1 and 2 can be used to form a silicon-containing thin film. For example, a silicon-containing thin film can be formed by depositing the precursor of Chemical Formula 1 and / or 2 onto a substrate using a PECVD process. The PECVD method generates a plasma of highly reactive substances to effectively decompose and excite the silicon precursor, and the silicon precursor can react with the reactive gas and polymerize on the substrate to form a silicon-containing thin film.

[0046] The formed silicon-containing thin film may include a SiOCH film. Specifically, for example, the silicon-containing thin film deposited using the silicon precursor in which A is cyclopentyl in Chemical Formulas 1 and 2 may include a SiOCH film having a structure represented by the following Chemical Formula A. However, the present disclosure is not limited thereto.

[0047] The SiOCH film having the structure represented by Chemical Formula A may form nanopores inside the thin film due to cyclopentyl (which is a cycloalkane functional group), and since the cycloalkane may include a plurality of C-H x bond structures.

[0048] [Chemical Formula A]

[0049] For example, the thickness of the silicon-containing thin film may be 0.1 μm to 0.5 μm. In addition, due to the uniform distribution of micropores with a small nanoscale size, the silicon-containing film has excellent mechanical strength while having a low dielectric constant. Therefore, the silicon-containing thin film can be advantageously used as a dielectric layer between multilayer metal wirings in a semiconductor device.

[0050] Hereinafter, the process of depositing a silicon-containing thin film on a substrate by plasma-enhanced chemical vapor deposition using the silicon precursors of Chemical Formulas 1 and 2 will be described in detail.

[0051] A method for manufacturing a silicon-containing thin film having high hardness and a low dielectric constant, including supplying and stabilizing a substrate to a plasma deposition reactor, supplying a silicon precursor represented by Chemical Formulas 1 and / or 2 to the reactor, forming a silicon-containing thin film on the substrate by using plasma to polymerize the silicon precursor, and performing post-treatment on the thin film.

[0052]

[0053] The silicon precursors represented by Chemical Formulas 1 and 2 are the same as those described above, and thus repeated descriptions will be omitted.

[0054] First, supplying and stabilizing the substrate to the plasma deposition reactor is a step of supplying the substrate to the reaction chamber of the plasma deposition reactor and removing impurities from the upper part of the substrate and the inside of the chamber. For example, after supplying the substrate, an inert gas such as argon or helium may be purged in the chamber to remove impurities. However, the present disclosure is not limited thereto. Therefore, by removing impurities to suppress by-products generated due to side reactions, a high-quality thin film can be formed. After removing the impurities, the inside of the chamber is maintained in a vacuum state for the reaction.

[0055] Next, a silicon precursor represented by Chemical Formulas 1 and / or 2 is supplied to the reactor. For example, the silicon precursor may be supplied in a bubbling manner using a bubbling tank.

[0056] Specifically, a silicon precursor represented by Chemical Formula 1 and / or 2 is supplied to a bubbling tank. When the bubbling tank is heated, the silicon precursor can be vaporized inside the bubbling tank. The vaporized silicon precursor can flow through a delivery pipe and be injected into a reactor.

[0057] Optionally, if needed, the silicon precursor can be supplied together with a carrier gas or a dilution gas. The carrier gas does not react with the silicon precursor and is lighter than the silicon precursor, so it can easily transport the vaporized silicon precursor to the reaction chamber. The dilution gas is non-reactive with the silicon precursor, thus not causing side reactions, and its flow rate can be controlled to easily control the reaction, such as the growth rate of a thin film, etc.

[0058] For example, the carrier gas or the dilution gas can include one or more selected from argon (Ar), helium (He), and neon (Ne).

[0059] The carrier gas or the dilution gas can also be supplied by bubbling using the bubbling tank, but is not limited thereto. The supplied carrier gas or dilution gas can be transported together with the vaporized silicon precursor through the delivery pipe and injected into the reactor. At this time, the pressure of the carrier gas in the reactor can be 1×10 -1 torr to 100×10 -1 torr, but is not limited thereto.

[0060] The next step is to supply a reaction gas to the reactor. For example, the reaction gas includes at least one of nitrous oxide (N2O) and oxygen (O2). The reaction gas can react with the silicon precursors of Chemical Formulas 1 and 2 to form a high-quality thin film.

[0061] The next step is to react the silicon precursor by using plasma and deposit it on a substrate to form a silicon-containing thin film.

[0062] By supplying the silicon precursor and the reaction gas to the reactor and applying high-frequency energy through an RF power supply connected to the substrate, plasma particles can be formed. Therefore, the activated silicon precursor and the reaction gas can undergo a chemical reaction to form a silicon-containing thin film including a SiOCH film.

[0063] When forming the silicon-containing thin film, the temperature of the substrate can be 300°C to 400°C. Within this range, the reaction between the activated silicon precursor and the reaction gas is easy, and a high-quality silicon-containing thin film can be formed. However, the present disclosure is not limited thereto.

[0064] When forming the silicon-containing thin film, the power supplied to the reactor can be 10 W to 40 W. The thin film can be formed within this range. If the power is less than 10 W or greater than 40 W, it may not be possible to form a thin film with the desired levels of high hardness and low dielectric constant characteristics. However, the present disclosure is not limited thereto.

[0065] The next step is to post-process the polymer film. For example, the post-processing can be performed by any one of an inductively coupled plasma (ICP) processing technique, a rapid thermal annealing (RTA) technique, or a combination thereof. By forming the film in this way and then performing post-processing, the dielectric constant of the silicon-containing film can be further reduced.

[0066] A method of manufacturing a silicon-containing film having high hardness and low dielectric constant according to an embodiment of the present disclosure generates a plasma of highly reactive substances to effectively decompose and excite the silicon precursors of Chemical Formulas 1 and 2. Thus, the decomposed and excited precursors can undergo various chemical reactions and react with the reaction gas to form a silicon film on the substrate. The silicon-containing film manufactured in this way has a low dielectric constant due to the formation of nano-scale pores by the cycloalkyl group contained in the silicon precursor. In addition, the film has excellent mechanical strength by including a plurality of C-Hx bonding structures.

[0067] Therefore, according to the present disclosure, a silicon-containing film having high hardness and low dielectric constant can be manufactured using a single silicon precursor without adding auxiliary substances such as a pore-forming agent.

[0068] Hereinafter, the effects of the present disclosure will be described in more detail through examples. However, these examples are only for helping to understand the present disclosure, and the present disclosure is not limited to the following examples.

[0069] [Example 1]

[0070] 1) Preparation of precursor

[0071] In a flame-dried 2L Schlenk flask, 100 g (0.525 mol) of cyclopentyltrimethoxysilane and 1 L of n-hexane were added and stirred at room temperature. 169.5 ml (0.525 mol) of a methyllithium solution (3.1 M methyllithium in diethoxymethane) was added dropwise to the flask at 0 °C or below, and then the reaction solution was stirred at room temperature for 12 hours. The lithium salt produced after the reaction was filtered through a filter, and then the solvent was removed under reduced pressure and distilled under reduced pressure to obtain 36.63 g (yield 40%) of a colorless transparent liquid compound, cyclopentyl dimethoxymethylsilane.

[0072] 2) Manufacture of silicon-containing film

[0073] Using a PECVD apparatus, a silicon wafer was placed on the RF electrode in the reactor and maintained at 10 -2The vacuum state of the holder. Next, the prepared cyclopentyl dimethoxymethylsilane was added as a silicon precursor to the bubbling tank and heated to 75 °C to evaporate the precursor solution. 99.999% ultra-high purity argon (Ar) and helium (He) were used as carrier gases. The carrier gases passed through the bubbling tank and the delivery pipe, and the silicon precursor was injected through the nozzle of the reactor, and oxygen (O2) was added as a reaction gas for plasma deposition on the substrate. At this time, an AC power supply of 13.56 Hz and 40 W or less was provided to generate plasma, and plasma polymerization was carried out at a pressure of 1.0 Torr or less and a temperature of 400 °C or less. In this way, a film with a thickness of was fabricated.

[0074] [Example 2]

[0075] 1) Preparation of the precursor

[0076] In a flame-dried 2 L Schlenk flask, 100 g (0.525 mol) of cyclopentyltrimethoxysilane and 1 L of n-hexane were added and stirred at room temperature. 355.95 ml (1.103 mol) of a methyllithium solution (3.1 M methyllithium in diethoxymethane) was added dropwise to the flask at 0 °C or below, and then the reaction solution was stirred at room temperature for 12 hours. The lithium salt produced after the reaction was filtered through a filter, and then the solvent was removed under reduced pressure and then distilled under reduced pressure to obtain 35.77 g (yield 43%) of a colorless transparent liquid compound, cyclopentylmethoxydimethylsilane.

[0077] 2) Fabrication of the silicon-containing film

[0078] A film was fabricated in the same manner as in Example 1, except that the cyclopentylmethoxydimethylsilane prepared in Example 2 was used as the silicon precursor.

[0079] [Comparative Example 1]

[0080] Using a PECVD apparatus, a silicon wafer was placed on the RF electrode in the reactor and maintained at 10 -2 Torr of vacuum. Next, cyclopentyltrimethoxysilane (CPTMS) of Chemical Formula 1a was added as a silicon precursor to the bubbling tank and heated to 75 °C to evaporate the precursor solution. 99.999% ultra-high purity argon (Ar) and helium (He) were used as carrier gases. The carrier gases passed through the bubbling tank and the delivery pipe, and the silicon precursor was injected into the reactor through the nozzle of the reactor. Plasma was deposited on the substrate by introducing oxygen (O2) as a reaction gas. At this time, an AC power supply of 13.56 Hz and 40 W or less was provided to generate plasma, and plasma polymerization was carried out at a pressure of 1.0 Torr or less and a temperature of 400 °C or less.

[0081] [Chemical Formula 1a]

[0082] [Experimental Example]

[0083] Measure the refractive indices of the silicon thin films fabricated according to Example 1, Example 2, and Comparative Example 1, and perform FT-IR and H-NMR analyses on the silicon precursors. The results are shown in Table 1 below and Figures 1 to 4 as follows.

[0084] Figure 1 The H-NMR analysis results of the silicon precursor fabricated according to Example 1 are shown, Figure 2 and the H-NMR analysis results of the silicon precursor fabricated according to Example 2 are shown. Figure 3 The thermogravimetric analysis results of the silicon precursor fabricated according to Example 1 are shown, and Figure 4 the thermogravimetric analysis results of the silicon precursor fabricated according to Example 2 are shown.

[0085] [Table 1]

[0086] First, referring to Figure 1 and Figure 2 , the synthesis of cyclopentyl dimethoxymethylsilane according to Example 1 and cyclopentyl methoxydimethylsilane according to Example 2 can be confirmed based on the H-NMR analysis results.

[0087] Referring to Figure 3 , it can be confirmed that T 1 / 2 of the silicon precursor of Example 1 is about 100 °C, and T 1 / 2 of the silicon precursor of Example 2 is about 90 °C, and the half-life of Example 2 with a larger number of methyl groups is lower. It can be seen from this that when using the silicon precursor of Example 2, the silicon precursor is likely to evaporate during the deposition process, which is relatively beneficial for the process.

[0088] At the same time, referring to Table 1, it can be confirmed from the FT-IR analysis results that as the number of methyl groups increases, the proportion of the Si-CH3 bond also increases. Therefore, it can be confirmed that the Si-CH3 bond ratios of Examples 1 and 2 are higher than that of Comparative Example 1, and the Si-CH3 bond ratio of Example 2 is the highest. In addition, it can be confirmed that the higher the Si-CH3 bond ratio, the lower the refractive index. Therefore, it can be confirmed that Examples 1 and 2 have refractive indices lower than that of Comparative Example 1, and Example 2 has the lowest refractive index.

[0089] It can be seen from this that when using the silicon precursors according to Examples 1 and 2, a thin film with high hardness and low dielectric constant can be formed, which has excellent mechanical strength and a lower dielectric constant value compared with when using the precursor of Comparative Example 1.

[0090] Precursors for forming silicon-containing thin films, silicon-containing thin films, and methods of manufacturing silicon-containing thin films according to various embodiments of the present disclosure can be described as follows.

[0091] According to one embodiment of the present disclosure, the precursor for forming a silicon-containing thin film is represented by Chemical Formula 1 or 2 below.

[0092]

[0093] In Chemical Formulas 1 and 2, A is a cycloalkyl group having 4 to 7 carbon atoms, and R1, R4, and R5 are each independently selected from hydrogen and substituted or unsubstituted alkyl groups having 1 to 3 carbon atoms; R2, R3, and R6 are each independently an alkyl group having 1 or 2 carbon atoms.

[0094] According to another feature of the present disclosure, the precursor may have a vapor pressure of 0.03 mmHg to 0.2 mmHg at 25°C.

[0095] According to another feature of the present disclosure, in Chemical Formulas 1 and 2, A may each independently be cyclopentyl or cyclohexyl.

[0096] According to yet another feature of the present disclosure, the precursor may be selected from cyclopentyl diethoxymethylsilane, cyclopentyl dimethylethoxysilane, cyclohexyl dimethoxymethylsilane, and cyclohexyl dimethylmethoxysilane.

[0097] According to yet another feature of the present disclosure, the precursor may be selected from the compounds represented by Chemical Formulas 3 and 4 below.

[0098]

[0099] A silicon-containing thin film according to one embodiment of the present disclosure is manufactured by depositing the precursor.

[0100] According to another feature of the present disclosure, the thickness of the thin film may be 0.1 μm to 0.5 μm.

[0101] According to yet another feature of the present disclosure, the thin film may be formed by plasma-enhanced chemical vapor deposition (PECVD).

[0102] According to another feature of the present disclosure, the thin film may include a SiOCH film.

[0103] A method of manufacturing a silicon-containing thin film according to one embodiment of the present disclosure includes depositing a silicon precursor represented by Chemical Formula 1 or 2 on a substrate by plasma-enhanced chemical vapor deposition (PECVD).

[0104]

[0105] In Formulas 1 and 2, A is a cycloalkyl group having 4 to 7 carbon atoms, R1, R4, and R5 are each independently selected from hydrogen and substituted or unsubstituted alkyl groups having 1 to 3 carbon atoms, and R2, R3, and R6 are each independently alkyl groups having 1 or 2 carbon atoms.

[0106] According to another feature of the present disclosure, deposition on a substrate may include supplying a silicon precursor to a reactor and depositing the silicon precursor on the substrate by irradiating a plasma to form a silicon-containing film.

[0107] According to yet another feature of the present disclosure, the method may further include supplying a reaction gas to the reactor before irradiating the plasma.

[0108] According to another feature of the present invention, the reaction gas may include at least one of nitrous oxide (N2O) and oxygen (O 2) in.

[0109] According to yet another feature of the present disclosure, the silicon-containing film may include a SiOCH film.

[0110] According to another feature of the present disclosure, after forming the silicon-containing film, the method may further include post-treating the film, and the post-treatment may be performed by any one of an inductively coupled plasma (ICP) treatment process, a rapid thermal annealing (RTA) process, or a combination thereof.

[0111] Although various embodiments of the present disclosure have been described in detail with reference to the accompanying drawings, the present disclosure is not limited thereto and may be embodied in many different forms without departing from the technical concept of the present disclosure. Therefore, the various embodiments disclosed in the present disclosure are not intended to limit the technical spirit, but to describe the present disclosure, and the technical spirit of the present disclosure is not limited by the following embodiments. Therefore, it should be understood that the above embodiments are illustrative in all respects and do not limit the present disclosure. The protection scope of the present disclosure should be construed based on the appended claims, and all technical ideas within the equivalent scope should be construed as falling within the scope of the present disclosure.

Claims

1. A precursor for forming a silicon-containing thin film, wherein the silicon-containing thin film is represented by the following chemical formula 1 or 2: In Chemical Formulas 1 and 2, A is a cycloalkyl group having 4 to 7 carbon atoms, R1, R4 and R5 are each independently selected from hydrogen; and a substituted or unsubstituted alkyl group having 1 to 3 carbon atoms; and R2, R3 and R6 are each independently an alkyl group having 1 or 2 carbon atoms. 2 . The precursor for forming a silicon-containing thin film according to claim 1 , wherein the precursor has a vapor pressure of 0.03 mmHg to 0.2 mmHg at 25° C. 3 . The precursor for forming a silicon-containing thin film according to claim 1 , wherein in Chemical Formulas 1 and 2, A is each independently a cyclopentyl group or a cyclohexyl group.

4. The precursor for forming a silicon-containing thin film according to claim 1, wherein the precursor is selected from the group consisting of cyclopentyldiethoxymethylsilane, cyclopentyldimethylethoxysilane, cyclohexyldimethoxymethylsilane and cyclohexyldimethylmethoxysilane.

5. The precursor for forming a silicon-containing thin film according to claim 1, wherein the precursor is selected from the compounds represented by the following Chemical Formulas 3 and 4:

6. A silicon-containing thin film produced by depositing a precursor according to any one of claims 1 to 5. 7 . The silicon-containing thin film according to claim 6 , wherein the thickness of the thin film is 0.1 μm to 0.5 μm.

8. The silicon-containing thin film of claim 6, wherein the thin film is formed by plasma enhanced chemical vapor deposition (PECVD).

9. The silicon-containing thin film according to claim 6, wherein the thin film comprises a SiOCH film.

10. A method for producing a silicon-containing film, comprising: A silicon precursor represented by the following Chemical Formula 1 or 2 is deposited on the substrate by plasma enhanced chemical vapor deposition (PECVD): In Chemical Formulas 1 and 2, A is a cycloalkyl group having 4 to 7 carbon atoms, R1, R4 and R5 are each independently selected from hydrogen; and a substituted or unsubstituted alkyl group having 1 to 3 carbon atoms, and R2, R3 and R6 are each independently an alkyl group having 1 or 2 carbon atoms.

11. The method for manufacturing a silicon-containing thin film according to claim 10, wherein the depositing on the substrate comprises: supplying the silicon precursor to a reactor; as well as The silicon precursor is deposited on the substrate by irradiating plasma to form the silicon-containing thin film.

12. The method for manufacturing a silicon-containing thin film according to claim 11, further comprising: A reaction gas is supplied to the reactor before irradiating the plasma.

13. The method for manufacturing a silicon-containing thin film according to claim 12, wherein the reaction gas comprises at least one of nitric oxide (N2O) and oxygen (O2).

14. The method for manufacturing a silicon-containing thin film according to claim 11, wherein the silicon-containing thin film comprises a SiOCH film.

15. The method for manufacturing a silicon-containing thin film according to claim 11, further comprising: performing post-treatment on the silicon-containing film after forming the film, The post-treatment is performed by any one of an inductively coupled plasma (ICP) treatment process, a rapid thermal annealing (RTA) process or a combination thereof.

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