Precursor for forming silicon containing thin film with high-strength and low-dielectric constant and manufacturing method of silicon containing thin film using the same

Abstract

To provide a high strength low dielectric constant thin film having an excellent mechanical strength even though having a low dielectric constant, and a manufacturing method of the same.SOLUTION: A precursor for a silicon containing thin film formation according to one embodiment of the present invention is a compound represented by a chemical formula 1 or a chemical formula 2 below. In the chemical formula 1 and the chemical formula 2, A is a cycloalkyl group with a carbon number of 4 to 7, R1, R4, and R5 are independently selected from hydrogen and a substituted or an unsubstituted alkyl group with a carbon number of 1 to 3, and R2, R3, and R6 are independently an alkyl group with a carbon number of 1 or 2. Accordingly, the present invention can provide a silicon containing thin film having high-strength and low-dielectric properties by utilizing a silicon precursor with an asymmetric structure containing a cycloalkyl group.SELECTED DRAWING: Figure 1

Description

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 same, and more particularly, to a silicon-containing thin film having high strength and low dielectric constant characteristics and a method for manufacturing the same.

Background Art

[0002] As electronic technology develops, the demand for miniaturization and weight reduction of semiconductor elements used in various electronic devices has been rapidly increasing. In order to form fine semiconductor elements, various physical and chemical vapor deposition methods have been proposed, and various studies are underway to form metal-containing thin films, dielectric thin films, etc. by such vapor deposition methods.

[0003] On the other hand, when manufacturing semiconductor elements, silicon dioxide (SiO2) or silicon oxyfluoride (SiOF), which are mainly used as interlayer insulating films, have problems such as high capacitance and resistance capacitance delay (RC delay) during the manufacture of ultra-high integrated circuits with a line width of 0.5 μm or less. Therefore, in order to reduce the resistance capacitance delay of the multilayer metal film used in the integrated circuit of the semiconductor element, research has been actively carried out in recent years to form the interlayer insulating film used for the metal wiring with a material having a low dielectric constant (relative dielectric constant, k ≤ 3.0). Such low dielectric constant thin films may be formed of inorganic substances such as SiCOH films in which Si, O, C, H, etc. are mixed and amorphous carbon (a-C:F) films doped with fluorine, or may be formed of organic substances containing carbon (C).

[0004] Such silicon-based low dielectric constant thin films can be formed by a Spin-on Dielectric (SOD) or can be formed in a Chemical Vapor Deposition (CVD) process. A spin-on dielectric film means an insulating film formed by spin-on coating a silicon precursor material and then performing a heat treatment (for example, 300°C to 600°C) to convert it into a silicon oxide film. In the case of an insulating film formed in this way, there are problems such as a relatively low heat resistance limit temperature (about 450°C or lower), poor thermal stability, volume shrinkage occurring after heat treatment, and low mechanical strength. Also, there are problems such as poor adhesion to upper and lower wiring materials, high stress due to heat curing, and a change in dielectric constant due to adsorption of surrounding moisture, resulting in poor device reliability.

[0005] In the chemical vapor deposition process, a thin film can be formed by a thermal induction chemical reaction between a precursor material and a reactive gas on the surface of a substrate. Therefore, although the deposition process is carried out under high-temperature conditions, in this case, there is a problem that the structure of the device having a layer formed on the substrate is damaged by the high temperature.

[0006] To solve such problems, a Plasma Enhanced Chemical Vapor Deposition (PECVD) method that can deposit metal and dielectric thin films at a relatively low temperature has been proposed.

[0007] In the plasma enhanced CVD process, high-frequency (RF) energy is applied to the reaction region to promote the excitation and / or dissociation of the reactive gas and generate a plasma of highly reactive species. Due to the high reactivity of the plasma thus generated, the energy required for a chemical reaction to occur is reduced. Therefore, in such a plasma enhanced CVD process, the temperature required for thin film formation can be lowered. With the introduction of such devices and methods, the size of the structure of semiconductor devices has been significantly reduced. SUMMARY OF THE INVENTION PROBLEMS TO BE SOLVED BY THE INVENTION

[0008] Conventionally, as silicon precursors used to form low dielectric constant silicon thin films, there are octamethylcyclotetrasiloxane (OMCTS), diethoxymethylsilane (DEMS), tetraethoxysilicate (TEOS), and the like. Such precursors exist in a liquid state at normal temperature and are excellent in the ease of the process, but have the disadvantages that pores having a large size and a non-uniform distribution are formed in the thin film and the hardness is low. Therefore, the mechanical strength of the thin film is insufficient, there are various difficulties in manufacturing semiconductor elements, and the applicable range is limited.

[0009] Therefore, an object of the present invention is to provide a high-strength low dielectric constant thin film having a low dielectric constant and excellent mechanical strength, and a method for manufacturing the same. The problems of the present invention are not limited to the problems mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the following description.

Means for Solving the Problems

[0010] The silicon-containing thin film-forming precursor according to an embodiment of the present invention is represented by the following Chemical Formula 1 or Chemical Formula 2.

[0011]

Table 1

[0012] In Chemical Formula 1 and Chemical Formula 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.

[0013] The silicon-containing thin film according to an embodiment of the present invention is manufactured by depositing the precursor. The method for manufacturing a silicon-containing thin film according to an embodiment of the present invention includes a step of depositing a silicon precursor represented by Chemical Formula 1 or Chemical Formula 2 on a substrate by Plasma Enhanced Chemical Vapor Deposition (PECVD).

[0014] Specific matters of other embodiments are included in the detailed description and the drawings.

Effects of the Invention

[0015] The silicon precursor represented by Chemical Formula 1 or Chemical Formula 2 according to an embodiment of the present invention is a silicon compound having an asymmetric structure containing a cycloalkyl group. When a silicon thin film is formed using the same, it is possible to provide a high-strength low-dielectric constant thin film having excellent mechanical strength while having a low dielectric constant. Further, it may be possible to form a silicon-containing thin film having a high strength and a low dielectric constant by using a single silicon precursor without separately supplying a substance such as a halogen.

[0016] In addition, the silicon compound having an asymmetric structure containing a cycloalkyl group according to an embodiment of the present invention has a high vapor pressure at a low process temperature, and enables smooth supply of a reactive gas to the surface of the substrate during thin film deposition.

[0017] In addition, the silicon precursor according to an embodiment of the present invention can be easily decomposed when energy is applied in the thin film formation process. Therefore, it is possible to form a thin film having low dielectric constant characteristics, and there is an advantage that the bonding ratio of Si-CH3 in the thin film can be easily adjusted.

[0018] The effects according to the present invention are not limited to the contents illustrated above, and more various effects are included in the present invention.

Brief Description of the Drawings

[0019]

Figure 1

Figure 2

Figure 3

Figure 4

BEST MODE FOR CARRYING OUT THE INVENTION

[0020] The advantages and features of the present invention, and the method for achieving them, will become clear by referring to the examples described in detail below together with the accompanying drawings. However, the present invention is not limited to the examples disclosed below, and is embodied in various different shapes. Merely, these examples are provided so that the disclosure of the present invention becomes complete and that those with ordinary knowledge in the technical field to which the present invention pertains are fully informed of the scope of the invention. The present invention is only defined by the scope of the claims.

[0021] In explaining the present invention, when it is determined that a specific explanation of related known technologies may obscure the gist of the present invention, the detailed explanation thereof is omitted. When terms such as "including," "having," "made" are used in the present invention, other parts may be added as long as "only" is not used. When a component is expressed in the singular, it includes the case of including a plurality unless otherwise explicitly stated.

[0022] In interpreting a component, it is interpreted as including an error range even without a separate explicit description. The silicon precursor for forming a silicon-containing thin film according to an embodiment of the present invention can be represented by the following Chemical Formula 1 or Chemical Formula 2.

[0023]

Table 2

[0024] R1 in Chemical Formula 1, R4 and R5 in Chemical Formula 2 can each independently be selected from hydrogen and alkyl groups having 1 to 3 carbon atoms. For example, in Chemical Formula 1, R1, and in Chemical Formula 2, R4 and R5 can each independently be selected from a methyl group and an ethyl group. Preferably, for example, in Chemical Formula 1, R1, and in Chemical Formula 2, R4 and R5 can each be a methyl group. In this case, a thin film with a low vapor pressure, an easy deposition process, and a high deposition rate can be formed.

[0025] For example, the alkyl group having 1 to 3 carbon atoms can be substituted with one or more substituents among an amino group, a hydroxyl group, a cyano group, a halogen group, a nitro group, and an alkoxy group, but is not limited thereto.

[0026] R2 and R3 in Chemical Formula 1, and R6 in Chemical Formula 2 can each independently be an alkyl group having 1 or 2 carbon atoms. For example, in Chemical Formula 1, R2 and R3, and in Chemical Formula 2, R6 can each be a methyl group. In this case, a thin film with a low vapor pressure, an easy deposition process, and a high deposition rate can be formed.

[0027] In Chemical Formulas 1 and 2, A is a cycloalkyl group having 4 to 7 carbon atoms. The cycloalkyl group is a functional group of a cyclic saturated hydrocarbon structure, and when forming a thin film deposition, it forms nano-pores in the thin film to provide a silicon-containing thin film with excellent strength and low dielectric constant characteristics. In addition, the cyclic saturated hydrocarbon contains a large number of C-Hx bond structures and can provide a thin film with excellent mechanical strength and elasticity.

[0028] Optionally, selectively, the cycloalkyl group having 4 to 7 carbon atoms can further contain a substituent. For example, the cycloalkyl group having 4 to 7 carbon atoms can be substituted with one or more substituents among an alkyl group having 1 to 6 carbon atoms, an amino group, a hydroxyl group, a cyano group, a halogen group, a nitro group, and an alkoxy group, but is not limited thereto.

[0029] For example, in Chemical Formula 1 and Chemical Formula 2, A can be independently 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 Chemical Formula 2 has the advantages of being thermally stable, having a low dielectric constant, and excellent strength.

[0030] For example, the precursor for forming a silicon thin film can be selected from cyclopentyldiethoxymethylsilane, cyclopentyldimethylethoxysilane, cyclohexyldimethoxymethylsilane, and cyclohexyldimethylmethoxysilane. In this case, it is even more excellent in the strength of the thin film formed during vapor deposition, has a low dielectric constant, and can be utilized as various elements.

[0031] Specifically, for example, the silicon precursor can be selected from the compounds represented by the following Chemical Formula 3 and the following Chemical Formula 4.

[0032]

Table 3

[0033] The silicon precursors according to Chemical Formula 3 and Chemical Formula 4 have an asymmetric structure in which a cyclopentyl group or a cyclohexyl group with a bulky structure is bonded to Si, and a methoxy group and a methyl group. Therefore, nano-pores are effectively formed on the substrate during vapor deposition. The thin film formed in this way is thermally stable, and nano-pores are formed by the bulky cyclopentyl group or cyclohexyl group, and has low dielectric constant characteristics. Therefore, it has the advantages of excellent mechanical strength, high strength and low dielectric characteristics, and is suitable for semiconductor elements. In addition, the thin film formed from the silicon precursor of the present invention can maintain effective low dielectric characteristics even when the power is increased.

[0034] According to the present invention, when manufacturing a silicon-containing thin film, a high-strength low-dielectric-constant silicon-containing thin film can be formed by using only the silicon precursors of Chemical Formula 1 and / or Chemical Formula 2 without adding auxiliary substances such as halogen compounds. Specifically, since the silicon precursors of Chemical Formula 1 and Chemical Formula 2 according to the present invention contain a cycloalkyl group, nano-pores can be formed inside the thin film without using a compound such as a halogen in addition to the silicon precursor.

[0035] Further, the silicon precursor of the present invention is a single molecule having an asymmetric structure in which one silicon atom is contained in one molecule, and since it has a low vapor pressure, a thin film can be formed at a high deposition rate during the deposition process. Therefore, a silicon thin film having a lower dielectric constant while satisfying the mechanical strength level required in the semiconductor process can be formed.

[0036] Also, if necessary, there is an advantage that it is easy to adjust the carbon content in the silicon-containing thin film, and through this, a thin film having a desired dielectric constant can be easily manufactured while improving the mechanical strength.

[0037] In addition, the thin film formed of the silicon precursors of Chemical Formula 1 and Chemical Formula 2 according to the present invention is thermally stable and has a very low level of low-dielectric-constant characteristics, so it is suitable for the manufacturing process of semiconductor elements. Further, by providing a thin film with a low dielectric constant, it can be used instead of the dielectric layer conventionally used for the metal multilayer wiring of semiconductor elements. In this case, the resistance capacitance signal delay increased by the miniaturization and integration of the metal multilayer wiring can be improved to improve the performance of the element.

[0038] As described above, the silicon precursor according to the present invention contains one silicon atom in one molecule. Therefore, it has the characteristic of having a low vapor pressure. For example, the silicon precursors represented by Chemical Formula 1 and Chemical Formula 2 may have a vapor pressure of 0.03 mmHg to 0.2 mmHg at 25°C.

[0039] Thus, by having the property of low vapor pressure, the silicon precursors of Chemical Formula 1 and Chemical Formula 2 can be easily supplied in the vapor phase to the reactor during thin film formation through a Plasma Enhanced Chemical Vapor Deposition (PECVD) process. Specifically, the silicon precursors of Chemical Formula 1 and Chemical Formula 2 of the present invention can be advantageously used to supply the precursor material to the reactor using a bubbler. Furthermore, a silicon-containing thin film with excellent deposition rate can be provided.

[0040] In addition, the silicon precursors of Chemical Formula 1 and Chemical Formula 2 contain a cyclic saturated hydrocarbon structure, which contains a large number of C-Hx structures, can provide a thin film with excellent mechanical strength and improved elasticity.

[0041] The precursors of Chemical Formula 1 and Chemical Formula 2 can be used for the formation of a silicon-containing thin film. For example, the silicon-containing thin film may be formed by depositing the precursor of Chemical Formula 1 and / or Chemical Formula 2 on a substrate using a plasma enhanced chemical vapor deposition process. The plasma enhanced chemical vapor deposition method generates a plasma of highly reactive species to effectively decompose and excite the silicon precursor, which can react with the reaction gas and polymerize on the substrate to form a silicon-containing thin film.

[0042] The silicon-containing thin film formed thereby can include a SiOCH film. Specifically, for example, a silicon-containing thin film deposited using a silicon precursor in which A is a cyclopentyl group in Chemical Formula 1 and Chemical Formula 2 can include a SiOCH film having a structure represented by Chemical Formula A below. However, it is not limited thereto.

[0043] The SiOCH film having the structure represented by Chemical Formula A forms nano-pores inside the thin film by a cyclopentyl group which is a cyclic hydrocarbon functional group, and can contain a large number of C-H x bonding structures due to the cyclic hydrocarbon.

[0044] [Table 4]

[0045] For example, the thickness of the silicon-containing thin film may be from 0.1 μm to 0.5 μm. Further, the silicon-containing thin film has characteristics in which fine voids having a size of nanometers or less are uniformly distributed, and although it has a low dielectric constant, it has excellent mechanical strength. Therefore, the silicon-containing thin film can be advantageously used as a dielectric layer between multilayer metal wirings in semiconductor elements.

[0046] In the following, the step of depositing a silicon-containing thin film on a substrate by a plasma-enhanced chemical vapor deposition method using the silicon precursors of Chemical Formula 1 and Chemical Formula 2 will be specifically described. A method for manufacturing a high-strength and low-dielectric-constant silicon-containing thin film includes a step of supplying a substrate to a plasma deposition reactor and stabilizing it, a step of supplying a silicon precursor represented by Chemical Formula 1 and / or Chemical Formula 2 to the reactor, a step of using plasma to polymerize the silicon precursor substance to form a silicon-containing thin film on the substrate, and a step of post-treating the thin film.

[0047]

Table 5

[0048] Since the silicon precursors represented by Chemical Formula 1 and Chemical Formula 2 are the same as those described above, duplicate descriptions are omitted. First, the step of supplying a substrate to a plasma deposition reactor and stabilizing it is a step of supplying the substrate to the reaction chamber of the plasma deposition reactor and removing impurities above the substrate and inside the chamber. For example, after supplying the substrate, an inert gas such as argon or helium can be purged into the chamber to remove impurities. However, it is not limited to this. By removing impurities in this way, the generation of by-products due to side reactions can be suppressed, and 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.

[0049] Next, a silicon precursor represented by Chemical Formula 1 and / or Chemical Formula 2 is supplied to the reactor. For example, the silicon precursor substance can be supplied in a bubbling manner using a bubbler. Specifically, when the silicon precursor represented by Chemical Formula 1 and / or Chemical Formula 2 is supplied into the bubbler and the bubbler is heated, the silicon precursor can be vaporized in the bubbler. The vaporized silicon precursor substance can flow through a transport pipe and be injected into the reactor.

[0050] Optionally, the silicon precursor can be selectively supplied together with a carrier gas or a dilution gas. The carrier gas has no reactivity with the silicon precursor, is lighter than the silicon precursor, and can easily transfer the vaporized silicon precursor to the reaction chamber. The dilution gas has no reactivity with the silicon precursor, does not induce side reactions, and enables easy control of reactions such as the growth rate of the thin film by controlling its flow rate.

[0051] For example, the carrier gas or dilution gas can include one or more selected from argon (Ar), helium (He), and neon (Ne). The carrier gas and the dilution gas can also be supplied in a bubbling manner using a bubbler, but are not limited thereto. The supplied carrier gas and dilution gas can move through the transport pipe together with the vaporized silicon precursor and be 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.

[0052] Next is the step of supplying a reaction gas to the reactor. For example, the reaction gas includes one or more of nitrogen monoxide (N2O) and oxygen (O2). The reaction gas can react with the silicon precursors of Chemical Formula 1 and Chemical Formula 2 to form a high-quality thin film.

[0053] Next is the step of reacting and depositing the silicon precursor on the substrate using plasma to form a silicon-containing thin film. When a silicon precursor and a reaction gas are supplied into a reactor and high-frequency energy is applied through an RF power source connected to a substrate, plasma particles can be formed. The silicon precursor and the reaction gas activated in this way can chemically react to form a silicon-containing thin film including an SiOCH film.

[0054] In the step of forming the silicon-containing thin film, the temperature of the substrate may 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, it is not limited to this.

[0055] In the step of forming the silicon-containing thin film, the power supplied to the reactor may be 10 W to 40 W. Thin film formation is possible within this range. If the power is less than 10 W or exceeds 40 W, a thin film having the target level of high-strength and low dielectric characteristics may not be formed. However, it is not limited to this.

[0056] Next is the step of post-treating the polymer thin film. For example, the post-treatment can be performed by any one of an inductively coupled plasma (ICP) treatment process, a rapid thermal annealing (RTA) process, or a combination thereof. After forming the thin film in this way, post-treatment can further lower the dielectric constant of the silicon-containing thin film.

[0057] The method for manufacturing a high-strength and low-dielectric constant silicon-containing thin film according to an embodiment of the present invention can generate a plasma of highly reactive species, so that the silicon precursors of Chemical Formula 1 and Chemical Formula 2 can be effectively decomposed and excited. The precursor substances decomposed and excited in this way can perform various chemical reactions, and a silicon thin film can be formed on the substrate by reacting with a reaction gas. The silicon-containing thin film manufactured in this way has nano-sized pores formed by the cycloalkyl group contained in the silicon precursor and has a low dielectric constant. Further, the thin film contains a large number of C-Hx bond structures and is excellent in mechanical strength.

[0058] Therefore, according to the present invention, a high-strength and low-dielectric-constant silicon-containing thin film can be manufactured by using a single silicon precursor substance without adding auxiliary substances such as porogens. Hereinafter, the effects of the present invention will be described in more detail through examples. However, this is only presented to assist in understanding the present invention, and the present invention is not limited to the following examples.

[0059] [Example 1] 1) Production of precursor In a 2L Schlenk flask dried by flame, 100 g (0.525 mol) of cyclopentyltrimethoxysilane and 1 L of n-hexane were charged and stirred at room temperature. 169.5 ml (0.525 mol) of a methyllithium solution (methyllithium in diethoxymethane 3.1 M) was added dropwise to the flask at 0 °C or lower, and then the reaction solution was stirred at room temperature for 12 hours. The lithium salt generated after the reaction was filtered through a filter, the solvent was removed under reduced pressure, and then distilled under reduced pressure to obtain 36.63 g (yield 40%) of a colorless transparent liquid compound, cyclopentyl dimethoxy methyl silane.

[0060] 2) Production of silicon-containing thin film Using a PECVD apparatus, a silicon wafer was placed on the RF electrode in the reactor, and 10 -2Maintain a vacuum state at the Torr level. Next, put the cyclopentyldimethoxymethylsilane produced above as a silicon precursor into a bubbler canister, heat it to 75 °C to vaporize the precursor solution. Ultra-high purity argon (Ar) and helium (He) gases of 99.999% were used as carrier gases. The carrier gas was passed through the bubbler, through the transport pipe, through the showerhead of the reactor to inject the silicon precursor, and oxygen (O2) was introduced as a reaction gas to perform plasma deposition on the substrate. At this time, an AC power supply of 13.56 Hz and 40 W or less was supplied for plasma generation, and plasma polymerization proceeded at a pressure of 1.0 Torr or less and a temperature of 400 °C or less. Through this, a thin film with a thickness of 4000 Å was manufactured.

[0061] [Example 2] 1) Production of precursor In a 2 L Schlenk flask dried by flame, 100 g (0.525 mol) of cyclopentyltrimethoxysilane and 1 L of n-hexane were added, and then stirred at room temperature. 355.95 ml (1.103 mol) of a methyllithium solution (methyllithium in diethoxymethane 3.1 M) was added dropwise to the flask at 0 °C or lower, 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, 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.

[0062] 2) Production of silicon-containing thin film A thin film was produced in the same manner as in Example 1, except that cyclopentylmethoxydimethylsilane produced in Example 2 was used as the silicon precursor.

[0063] [Comparative Example 1] Using a PECVD apparatus, a silicon wafer was placed on the RF electrode in the reactor, 10 -2Maintain a vacuum state at the Torr level. Next, as the silicon precursor material, cyclopentyl trimethoxysilane (CPTMS) of Chemical Formula 1a was placed in a bubbler canister and heated to 75 °C to vaporize the precursor solution. Ultra-high purity argon (Ar) and helium (He) gases of 99.999% were used as the carrier gas. The carrier gas was passed through a bubbler and through a transport pipe to inject the silicon precursor material into the reactor through the showerhead of the reactor. As the reaction gas, oxygen (O2) was introduced to perform plasma deposition on the substrate. At this time, an AC power supply of 13.56 Hz and 40 W or less was supplied for plasma generation, and plasma polymerization proceeded at a pressure of 1.0 Torr or less and a temperature of 400 °C or less.

[0064] [Table 6]

[0065] [Experimental Example] The refractive indices of the silicon thin films produced according to Example 1, Example 2, and Comparative Example 1 were measured, and FT-IR and H-NMR analyses of the silicon precursors were performed. The results thereof are shown in Table 1 and FIGS. 1 to 4 below.

[0066] FIG. 1 shows the H-NMR analysis result of the silicon precursor produced according to Example 1, FIG. 2 shows the H-NMR analysis result of the silicon precursor produced according to Example 2, FIG. 3 shows the thermogravimetric analysis result of the silicon precursor produced according to Example 1, and FIG. 4 shows the thermogravimetric analysis result of the silicon precursor produced according to Example 2.

[0067] [Table 1]

[0068] [Table 7]

[0069] First, referring to FIGS. 1 and 2, from the H-NMR analysis results, the synthesis of cyclopentyldimethoxymethylsilane according to Example 1 and cyclopentylmethoxydimethylsilane according to Example 2 can be confirmed.

[0070] Referring to FIG. 3, for the silicon precursor of Example 1, T 1 / 2 is about 100° C., and for the silicon precursor of Example 2, T 1 / 2 is about 90° C., and it can be confirmed that the half-life of Example 2 with a larger number of methyl groups is even lower. From this, it can be seen that when using the silicon precursor of Example 2, it is easily vaporized in the deposition process and is relatively advantageous for the process.

[0071] On the other hand, referring to Table 1, from the FT-IR analysis results, it can be confirmed that the ratio of the Si—CH3 bond increases as the number of methyl groups 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 Example 2 has the highest Si—CH3 bond ratio. It can also be confirmed that the refractive index decreases as the Si—CH3 bond ratio increases. Therefore, it can be confirmed that Examples 1 and 2 have a lower refractive index than Comparative Example 1, and Example 2 has the lowest refractive index.

[0072] Through this, it can be seen that when using the silicon precursor substances according to Examples 1 and 2, compared with using the precursor of Comparative Example 1, it is excellent in mechanical strength, and it is possible to form a high-strength low-dielectric constant thin film having a lower dielectric constant value.

[0073] The precursor for forming a silicon-containing thin film, the silicon-containing thin film, and the method for manufacturing the silicon-containing thin film according to various embodiments of the present invention can be described as follows. The precursor for forming a silicon-containing thin film according to an embodiment of the present invention is represented by the following Chemical Formula 1 or Chemical Formula 2.

[0074]

Table 8

[0075] 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.

[0076] According to another feature of the present invention, the precursor may have a vapor pressure of 0.03 mmHg to 0.2 mmHg at 25°C. According to still another feature of the present invention, in Chemical Formulas 1 and 2, A may each independently be a cyclopentyl group or a cyclohexyl group.

[0077] According to still another feature of the present invention, the precursor may be selected from cyclopentyldiethoxymethylsilane, cyclopentyldimethylethoxysilane, cyclohexyldimethoxymethylsilane, and cyclohexyldimethylmethoxysilane.

[0078] According to still another feature of the present invention, the precursor may be selected from the compounds represented by the following Chemical Formula 3 and the following Chemical Formula 4.

[0079] [Table 9]

[0080] The silicon-containing thin film according to an embodiment of the present invention is manufactured by depositing the precursor. According to another feature of the present invention, the thickness of the thin film may be 0.1 μm to 0.5 μm. According to still another feature of the present invention, the thin film may be formed by plasma enhanced chemical vapor deposition (PECVD).

[0081] According to still another feature of the present invention, the thin film may contain a SiOCH film. The method for manufacturing a silicon-containing thin film according to an embodiment of the present invention includes a step of depositing a silicon precursor represented by Chemical Formula 1 or Chemical Formula 2 below on a substrate by Plasma Enhanced Chemical Vapor Deposition (PECVD).

[0082]

Table 10

[0083] 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.

[0084] According to another feature of the present invention, the step of depositing on the substrate may include a step of supplying a silicon precursor to a reactor and a step of irradiating plasma to deposit the silicon precursor on the substrate to form a silicon-containing thin film.

[0085] According to still another feature of the present invention, it may further include a step of supplying a reaction gas to the reactor before irradiating plasma. According to still another feature of the present invention, the reaction gas may include one or more of nitrous oxide (N2O) and oxygen (O2).

[0086] According to still another feature of the present invention, the silicon-containing thin film may include a SiOCH film. According to still another feature of the present invention, it further includes a step of post-treating the thin film after the step of forming the silicon-containing thin film, and the post-treatment step may be performed by any one method of an inductively coupled plasma (ICP) treatment step, a rapid thermal annealing (RTA) step, or a combination thereof.

[0087] In the above, the present invention has been described in detail through examples. However, the present invention is not necessarily limited to such examples, and can be variously modified and implemented within the scope not departing from the technical idea of the present invention. Therefore, the examples disclosed in the present invention are not for limiting the technical idea of the present invention, but for explanation, and the scope of the technical idea of the present invention is not limited by such examples. Therefore, it should be understood that the examples described above are illustrative in all aspects and not restrictive. The protection scope of the present invention should be interpreted by the following claims, and all technical ideas within the equivalent scope should be interpreted as being included in the scope of rights of the present invention.

Claims

1. A precursor for forming a silicon-containing thin film represented by the following formula 1 or 2: 【Table 1】 In the above Chemical Formula 1 and Chemical Formula 2, A is a cycloalkyl group having 4 to 7 carbon atoms; R １ , R ４ and R ５ are each independently selected from hydrogen; and a substituted or unsubstituted alkyl group having 1 to 3 carbon atoms; R ２ , R ３ and R ６ are each independently an alkyl group having 1 or 2 carbon atoms.

2. 2. The silicon-containing thin film-forming precursor according to claim 1, wherein the precursor has a vapor pressure of 0.03 mmHg to 0.2 mmHg at 25°C.

3. 2. The silicon-containing thin film precursor according to claim 1, wherein in the formula 1 and the formula 2, A is each independently a cyclopentyl group or a cyclohexyl group.

4. 2. The silicon-containing thin film-forming precursor 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, selected from the compounds represented by the following formula 3 and the following formula 4: 【Table 2】

6. 6. A silicon-containing thin film produced by vapor deposition of the precursor of any one of claims 1 to 5.

7. The silicon-containing thin film of 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 of claim 6 , wherein the thin film comprises a SiOCH film.

10. A method for producing a silicon-containing thin film, comprising the steps of depositing a silicon precursor represented by the following formula 1 or 2 on a substrate by plasma enhanced chemical vapor deposition (PECVD): 【Table 3】 In the above Chemical Formula 1 and Chemical Formula 2, A is a cycloalkyl group having 4 to 7 carbon atoms; R １ , R ４ and R ５ are each independently selected from hydrogen; and a substituted or unsubstituted alkyl group having 1 to 3 carbon atoms; R ２ , R ３ and R ６ are each independently an alkyl group having 1 or 2 carbon atoms.

11. The step of depositing on the substrate comprises: providing the silicon precursor to a reactor; and The method for producing a silicon-containing thin film according to claim 10, comprising irradiating a plasma to deposit the silicon precursor on the substrate to form a silicon-containing thin film.

12. The method for producing a silicon-containing thin film according to claim 11 , further comprising the step of supplying a reaction gas to the reactor before irradiating the plasma.

13. The reaction gas is nitric oxide (N ２ O) and oxygen (O ２ The method for producing a silicon-containing thin film according to claim 12, further comprising:

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

15. The method further includes a step of post-treating the thin film after the step of forming the silicon-containing thin film, 12. The method of claim 11, wherein the post-treatment step 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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