Precursor compound for forming thin film and method of manufacturing semiconductor device using the same

Abstract

The present technology provides a precursor compound for forming a thin film [Chemical Formula 1] and a method for preparing the same, in which pattern collapse of a photoresist layer can be prevented by reducing the exposure time of pattern formation and minimizing the thickness of a lower layer or omitting the lower layer during post-exposure etching, the lower layer having etching selectivity similar to that of a photoresist. (In the chemical formula 1, R0 is Si, Sn, Ge, Sb, In, Hf, Zr, Ti or Te; r1 is CH3, CF3, CH = CH2, halogen or phenyl; r2 and R2'are each independently an alkyl group or an alkoxy group; r3 is amine or halogen; r is hydrogen or halogen; and n is an integer of 1-7).

Description

TECHNICAL FIELD

[0001] The present disclosure relates to a precursor compound for forming a thin film and a method of manufacturing a semiconductor device, and to a precursor compound for forming an underlayer under a photoresist layer and a method of manufacturing a semiconductor device using the same. BACKGROUND

[0002] A photoresist technology is a technology of forming a high-resolution circuit within a semiconductor device by exposing a photoresist (hereinafter, referred to as "resist") on a substrate to a light source.

[0003] In general, the photoresist technology can be performed by the following method using a resist.

[0004] First, after a resist composition including a polymer matrix, a photoacid generator, a solvent, and other additives capable of improving performance is spin-coated on a silicon wafer, the resist composition is cured to form a resist film. Next, the formed resist film is exposed to a light source in a pattern form, and selective heating is performed, thereby inducing a post-exposure bake (PEB) chemical conversion. When a solubility difference between an exposed area and an unexposed area of the resist film is generated due to this chemical conversion, a resist pattern image is generated on the wafer by a developing process using a solvent. In the exposure process, radiation having a wavelength ranging from near ultraviolet (UV) to deep ultraviolet (DUV) and extreme ultraviolet (EUV) is generally used as a light source.

[0005] In this photoresist process, a stack in which a substrate, an underlayer, and a photoresist layer are stacked is generally used. In order to form a pattern on the stack, when etching is performed after exposure, a pattern is formed by selectively etching the underlayer. However, when an actual process is applied, since the photoresist layer on the surface of the stack is also etched when etching is performed after exposure, a pattern shape is not good, thereby reducing the performance of a semiconductor device. SUMMARY

[0006] Embodiments of the present disclosure provide a precursor compound for forming a thin film and a method of manufacturing the same, which can reduce an exposure time for forming a pattern, and also can prevent a pattern collapse of a photoresist layer by minimizing or omitting a thickness of an underlayer having an etching selectivity similar to that of the photoresist when etching is performed after exposure.

[0007] The precursor compound for forming a thin film according to the embodiments of the present disclosure can be a precursor compound for forming a thin film including a material of Chemical Formula 1.

[0008] [Chemical Formula 1]

[0009]

[0010] (In Chemical Formula 1, R0 Si, Sn, Ge, Sb, In, Hf, Zr, Ti, or Te, R 1 CH3, CF3, CH=CH2, halogen, or phenyl, R 2 and R 2 each independently alkyl or alkoxy, R 3 amine or halogen, R is hydrogen or halogen, and n is an integer of 1 to 7

[0011] Preferably, in Chemical Formula 1, R 0 may be Si or Sn, R 1 may be CF3or I, R 2 and R 2 may each independently be CH3, C2H5, C3H7, OCH3, or OC2H5, R 3 may be N(CH3)2or N[(CH2)CH3]2, and Rmay be H. In this case, in Chemical Formula 1, n can be an integer of 1 to 4.

[0012] A method of manufacturing a semiconductor device according to an embodiment of the disclosure can include preparing a substrate, preparing a precursor of a material including Chemical Formula 1 (i.e., a material for forming a lower layer), forming a lower layer by depositing the precursor of the material including Chemical Formula 1 on the substrate through an atomic layer deposition (ALD) method, and forming a photoresist layer on the lower layer.

[0013] The forming of the lower layer includes supplying the precursor of the material including Chemical Formula 1 and supplying a purge gas. The supply of the precursor and the supply of the purge gas define one cycle, which can be repeated at least once.

[0014] The present technology can reduce an exposure time for forming a pattern and also can prevent a pattern collapse of the photoresist layer by minimizing or omitting a thickness of the lower layer, which has an etching selectivity similar to that of the photoresist at the time of etching after exposure.

[0015] In addition, the lower layer can be formed as an ultra-thin film of and sufficient adhesion strength between the photoresist layer and the substrate can be ensured. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 is a diagram schematically showing a stacked structure of a semiconductor device 100 according to the present embodiment.

[0017] Figure 2 is a process flow diagram for describing a method of manufacturing a semiconductor device according to the present embodiment.

[0018] Figure 3 is a diagram simply explaining a process of depositing a precursor according to one embodiment. DETAILED DESCRIPTION

[0019] The terms or words used in the specification and the claims should not be understood as having a commonly used meaning or meaning in the dictionary, but should be interpreted as having a meaning and concept meeting the technical spirit of the present disclosure, with the principle that the inventor can appropriately define the concept of the terms in order to describe his or her disclosure in the best way.

[0020] The terms used in the specification are only used to describe the exemplary embodiments and are not intended to limit the present embodiments. Unless the context clearly dictates otherwise, the singular expression also includes the plural expression.

[0021] In each process, the symbols are used for convenience of description, and the symbols do not represent the order of the process. Unless a specific order is explicitly described in the context, the execution order of the process can be different from the order described in the context. That is, the process can be performed in the following order: the order, can be performed substantially simultaneously, or can be performed in reverse order.

[0022] It should be understood that in the present specification, the terms "include", "comprise", or "have" and the like are intended to denote the presence of the features, numbers, steps, components or combinations thereof, and do not exclude the presence or addition of one or more other features, numbers, steps, components or combinations thereof.

[0023] An atomic layer deposition (ALD) process can be performed using a. source gas input, b. purge, c. reaction gas input, and d. purge as one cycle, or can include a half ALD process, which is performed by using two processes a'. gas input and b' purge as one cycle. In the present specification, the "ALD process using a precursor compound of Chemical Formula 1" can be performed by a half ALD process.

[0024] Reference Figure 1 The present embodiments relate to a precursor compound for forming a thin film and a method of preparing the same. More specifically, a precursor compound for forming a lower layer 120 can be supplied onto a substrate 110, and a lower layer 120 can be formed under a photoresist layer 130.

[0025] The precursor compound for forming a thin film according to the present embodiments can be represented as Chemical Formula 1.

[0026] [Chemical Formula 1]

[0027]

[0028] (In Chemical Formula 1, R 0 is Si, Sn, Ge, Sb, In, Hf, Zr, Ti, or Te, R 1 is CH3, CF3, CH=CH2, halogen, or phenyl, R2 and R 2 each independently alkyl or alkoxy, R 3 is amine or halogen, R is hydrogen or halogen, and n is an integer of 1 to 7.

[0029] As the precursor including Chemical Formula 1, preferably, R 0 is Si or Sn, R 1 is CF3or I, R 2 and R 2 each independently CH3, C2H5, C3H7, OCH3or OC2H5, R 3 is N(CH3)2or N[(CH2)CH3]2, and a compound having an integer of 1 to 4 is used as n.

[0030] In the precursor of Chemical Formula 1, the precursors exemplarily represented as Chemical Formulas 2 to 9 can be applied.

[0031] [Chemical Formula 2]

[0032]

[0033] [Chemical Formula 3]

[0034]

[0035] [Chemical Formula 4]

[0036]

[0037] [Chemical Formula 5]

[0038]

[0039] [Chemical Formula 6]

[0040]

[0041] [Chemical Formula 7]

[0042]

[0043] [Chemical Formula 8]

[0044]

[0045] [Chemical Formula 9]

[0046]

[0047] The precursor material represented by Chemical Formula 1 is a precursor compound capable of forming a thin film or a metal thin film on a semiconductor substrate, and a hydrophobic group such as an alkyl group or an olefin is formed at one end thereof, and an amine group or a halogen group is formed at the other end thereof. The one end thereof can form a bonding force with the photoresist layer 130. The other end thereof can form a bonding force with the substrate 110.

[0048] Specifically, a carbon straight chain such as an alkyl group or an olefin is formed at one end of the precursor material represented by Chemical Formula 1. Thus, the bonding force due to the enhancement of the van der Waals force can be enhanced, and the bonding force due to the physical entanglement of the carbon straight chain with the photoresist layer 130 can be enhanced. Since the surface deposition coverage is improved by the formation of a self-assembled monolayer, the bonding force with the photoresist layer 130 can be improved; in addition, since R 1 is introduced, the bonding force with the photoresist layer 130, that is, the hydrophobicity, can be further improved due to the increase in the dipole moment.

[0049] In particular, when R 1 is CF3, the bonding force with the photoresist layer 130 is further improved due to the further enhancement of the hydrophobicity. Since the absorption rate of the EUV light source becomes excellent at the time of exposure for pattern formation, the EUV dose for pattern formation can be reduced.

[0050] In addition, if a halogen material is included as the functional group, since the halogen material itself has an excellent absorption efficiency, the EUV dose can be reduced.

[0051] Figure 2 is a process flow diagram for describing a method of manufacturing a semiconductor device according to the present embodiment. Referring to Figure 2 A method of manufacturing a semiconductor device according to the present embodiment is described. In addition, for the convenience of description, Figure 1 A semiconductor device manufactured according to the present embodiment is shown.

[0052] First, Figure 1 is a diagram schematically showing a stack structure of a semiconductor device 100 manufactured by a method of manufacturing a semiconductor device according to the present embodiment.

[0053] The semiconductor device 100 manufactured by the method of manufacturing a semiconductor device according to the present embodiment includes a substrate 110, a lower layer 120 formed on the substrate 110 by depositing a precursor of Chemical Formula 1, and a photoresist layer 130 formed on the lower layer 120.

[0054] [Chemical Formula 1]

[0055]

[0056] (In Chemical Formula 1, R 0 is Si, Sn, Ge, Sb, In, Hf, Zr, Ti, or Te, R1 CH3, CF3, CH=CH2, halogen or phenyl, R 2 and R 2 each independently alkyl or alkoxy, R 3 is amine or halogen, R is hydrogen or halogen, and n is an integer of 1 to 7.

[0057] The precursor of Chemical Formula 1 is the same as described above, and thus a repeated description thereof is omitted.

[0058] Elements, circuits, films, etc. can be formed in the substrate 110. The substrate includes a base substrate 111 and a surface film 112. The base substrate 111 can be formed of Group IV materials, such as silicon and germanium, or can be formed of compounds, such as Group III-V materials, such as GaAs, GaN, InP and InGaN, Group II-VI materials, such as ZnSe, and Group IV-IV materials, such as SiC and SiGe.

[0059] The surface of the substrate 110 can include silicon oxynitride (SiON) or amorphous carbon. Specifically, the surface film 112 including silicon oxynitride or amorphous carbon can be formed on the surface of the substrate. For example, the surface of the substrate 110 can include a silicon oxynitride film or an amorphous carbon film as the surface film 112.

[0060] As described above, the substrate 110 can include silicon oxynitride or amorphous carbon on the surface thereof. The surface of the substrate has a silicon oxynitride film. Thus, if the precursor of Chemical Formula 1 includes an amine group, a high bonding force with the substrate 110 can be formed. Thus, by depositing the precursor of Chemical Formula 1 on the substrate 110, a film can be easily formed.

[0061] The lower layer 120 can be formed by an ALD process or a semi-ALD process.

[0062] The lower layer 120 can be formed by depositing the precursor of Chemical Formula 1 on the substrate 110 by an ALD process. The thickness of the lower layer 120 can be or less, or can be to

[0063] The conventional lower layer 120 is formed by a spin coating method, and is formed relatively thickly to or more. In this case, the minimum light dose required to form a semiconductor pattern is large, and the etching time is long. Thus, there is a problem in that, although the lower layer 120 is selectively etched only in a pattern forming process, there is a problem in that the photoresist layer 130 is also etched, resulting in pattern collapse.

[0064] In the semiconductor device 100 according to the present embodiment, since the lower layer 120 is formed by using an ALD method, a thickness of or less. In this case, if the lower layer 120 is implemented in the form of an ultra-thin film, since the light dose for forming a pattern can be reduced and the etching time can be reduced, a pattern can be formed without damaging the photoresist layer 130. In addition, since the amount of etchant used at the time of etching can be reduced, the cost consumed by the process can be reduced.

[0065] The ALD method can include a process of first vaporizing a liquid precursor (denoted as Chemical Formula 1), depositing the precursor on the substrate 110, and purging the precursor. The process can be repeatedly performed by using deposition and purging as one cycle.

[0066] In this case, when the vaporized precursor of Chemical Formula 1 is delivered, an inert gas (for example, argon (Ar), nitrogen (N2), or helium (He)) can also be used as a carrier gas, but the type of the carrier gas is not limited thereto. In addition, the inert gas can be used as a purge gas used in the purging process, but the present disclosure is not limited thereto.

[0067] The photoresist layer 130 formed on the lower layer 120 can include at least one of a chemically amplified resist (CAR) type and a metal oxide resist (MOR) type.

[0068] Figure 2 is a process flow diagram for describing a method of manufacturing a semiconductor device 100 according to the present embodiment. Referring to Figure 2 A method of manufacturing a semiconductor device 100 according to the present embodiment is described.

[0069] The present embodiment includes a method of manufacturing a semiconductor device 100, including a process S10 of preparing a substrate 110, a process S20 of preparing a precursor of Chemical Formula 1 (i.e., a material for forming a lower layer 120), a process S30 of forming the lower layer 120 by depositing the precursor of Chemical Formula 1 on the substrate 110 through an atomic layer deposition (ALD) method, and a process S40 of forming a photoresist layer 130 on the lower layer 120.

[0070] The precursor of Chemical Formula 1 is the same as described above, and thus a repeated description thereof is omitted.

[0071] The process S10 is a process of preparing the substrate 110, and can be a process of loading the substrate 110 into a reaction chamber.

[0072] The substrate 110 has elements, circuits, films, etc. formed thereon. The substrate includes a base substrate 111 and a surface film 112. The base substrate 111 can be formed of a Group IV material, such as silicon and germanium, or can be formed of a compound, such as a Group III-V material like GaAs, GaN, InP, and InGaN, a Group II-VI material like ZnSe, and a Group IV-IV material like SiC and SiGe.

[0073] The surface of the substrate 110 can include silicon oxynitride or amorphous carbon. Specifically, a surface layer film 112 including silicon oxynitride or amorphous carbon can be formed on the surface of the substrate. For example, the surface of the substrate 110 can include a silicon oxynitride film or an amorphous carbon film as the surface layer film 112.

[0074] The process S20 is a process of preparing a precursor including Chemical Formula 1, i.e., a material for forming the lower layer 120. The precursor including Chemical Formula 1 is in a liquid state at room temperature. In this process, in order to apply the precursor to the ALD method, the precursor can be vaporized through a vaporizer.

[0075] The process S30 is a process of forming the lower layer 120 by supplying the precursor including Chemical Formula 1 to the chamber and allowing the precursor to react therein. This process can be repeatedly performed for at least one cycle. The one cycle includes the process S31 of supplying the precursor including Chemical Formula 1 and the process S32 of supplying a purge gas. This process can be performed at a temperature ranging from 100°C to 250°C. According to the R 0 to R 3 The defined precursor has a different decomposition temperature according to the type of the precursor. Therefore, it is preferable to perform this process at a temperature lower than the decomposition temperature of the corresponding precursor.

[0076] In the process S31, the vaporized precursor including Chemical Formula 1 is supplied to the chamber in which the substrate 110 is accommodated. In this case, an inert gas such as argon (Ar), nitrogen (N2), or helium (He) can be supplied to the chamber together with the vaporized precursor including Chemical Formula 1 as a carrier gas.

[0077] The amine group formed at one end of the precursor supplied to the chamber in which the substrate 110 is accommodated has hydrophilicity and can be deposited on the thin film on the surface of the substrate 110 by bonding and combining with the silicon oxynitride or amorphous carbon having hydrophilicity on the surface of the substrate 110. Specifically, the amine group of the precursor including Chemical Formula 1 can form a reaction portion as the amine group is stripped at a high temperature, and form a monolayer in which the amine group is arranged in a row by bonding and combining with the hydroxyl group, the amino group, or the sp2 carbon (i.e., a nucleophile) on the surface of the substrate 110. Referring to Figure 3 This series of processes can be more clearly understood.

[0078] Figure 3 is a diagram simply illustrating a process of depositing a precursor according to one embodiment. In Figure 3 In the illustrated embodiment, R of the precursor represented by Chemical Formula 1 is explained as an example of a precursor, i.e., H.

[0079] First, when the precursor of Chemical Formula 1 is exposed to heat, R of the precursor 0 is bonded with the unsaturated bond, the hydroxyl group, or the amino group (i.e., a nucleophile) of the surface layer film 112 on the surface of the substrate 110. While R 3peeling. Thus, the precursors including Chemical Formula 1 on the surface of the surface layer film 112 can be combined in a row to form a monolayer.

[0080] Meanwhile, a process S32 is performed to purge the unreacted reactants and by-products (including gas products generated by the reaction) in the previous process, which can be performed by supplying an inert gas to the chamber. In this case, for example, argon (Ar), nitrogen (N2), or helium (He) can be used as the inert gas, but the present disclosure is not limited thereto.

[0081] The process S40 is a process of forming a photoresist layer 130 on the lower layer 120, which can be a process of forming the photoresist layer 130 on the lower layer 120 by using an ALD method. In this case, the photoresist layer 130 can be formed of any one material among a chemical amplified resist (CAR) type and a metal oxide resist (MOR) type, or can simultaneously include the CAR type and the MOR type.

[0082] As described above, the lower layer 120 is formed in a monolayer form in which the precursors including Chemical Formula 1 are arranged in a row. In this case, the hydrophilic portion is located at one side of the substrate 110, and the hydrophobic portion of the alkyl or olefin carbon chain structure is located at the other side thereof. When the lower layer 120 is deposited on the substrate 110 through the process of forming the lower layer 120, the surface of the lower layer 120 exposed to the outside has hydrophobicity. Thus, when the photoresist layer 130 is formed on the surface of the lower layer 120 having hydrophobicity by using a photoresist material, a strong bonding force is formed between the surface of the lower layer 120 having hydrophobicity and the photoresist layer 130 having hydrophobicity due to the action of van der Waals force. The carbon chain structure of the precursors including Chemical Formula 1 can form an additional bonding force by entangling with the photoresist layer 130. In particular, when R 1 of Chemical Formula 1 is CF3or a phenyl group, the bonding force with the photoresist layer is further improved. When R 1 of Chemical Formula 1 is CF3, the bonding force is most excellent.

[0083] The semiconductor device 100 according to the present embodiment can reduce the EUV dose for forming a pattern since the EUV absorbance of the lower layer 120 is improved. The lower layer 120 is formed by an ALD process from a thin film of 10 or thinner. Thus, since the EUV exposure time of the photoresist layer 130 and the time for which the photoresist layer is exposed to an etchant can be reduced, damage (pattern collapse) to the photoresist layer 130 can be prevented. The process cost can be reduced and the process time can be reduced by reducing the dose, reducing the amount of etchant, reducing the time for forming a pattern, etc.

[0084] Further, compared to the semiconductor device 100 of the comparative example in which the lower layer 120 is formed using the conventional spin coating process, the semiconductor device 100 according to the present embodiment has similar minimum critical dimension (CD) values with reduced line width roughness (LWR) and pattern collapse, but can significantly reduce the dose (DtS). It can be seen that the DtS is reduced by about 3% to 30% compared to the conventional spin coating method.

[0085] The above has described the embodiments of the present disclosure, but those skilled in the art can make various modifications and changes to the present disclosure by supplementing, changing, deleting, or adding components, etc. without departing from the spirit of the present disclosure recited in the claims. All such embodiments can be considered to belong to the scope of the present disclosure.

[0086] Industrial applicability

[0087] According to the present disclosure, the method of manufacturing a semiconductor device using a precursor compound for forming a thin film has industrial applicability because it has the effect of being able to reduce the exposure time for forming a pattern and prevent the collapse of the pattern of the photoresist layer by minimizing or omitting the thickness of the lower layer having an etching selectivity similar to the photoresist upon etching after exposure.

Claims

1. A precursor compound for forming a thin film, the precursor compound comprising a material of Chemical Formula 1 [Chemical Formula 1] (In Chemical Formula 1, R 0 is Si, Sn, Ge, Sb, In, Hf, Zr, Ti, or Te, R 1 is CH3, CF3, CH=CH2, halogen, or phenyl, R 2 and R 2 are each independently alkyl or alkoxy, R 3 is amine or halogen, R is hydrogen or halogen, and n is an integer of 1 to 7).

2. The precursor compound according to claim 1, wherein, In the chemical formula 1, R 0 is Si or Sn, R 1 is CF3or I, R 2 and R 2 are each independently CH3, C2H5, C3H7, OCH3or OC2H5, R 3 is N(CH3)2or N[(CH2)CH3]2, and wherein R is H.

3. The precursor compound according to claim 2, wherein, n in Chemical Formula 1 is an integer of 1 to 4.

4. The precursor compound of claim 1, wherein, The precursor compound for forming a thin film is any one of materials shown in the following Chemical Formula 2 to Chemical Formula 9: [Chemical Formula 2] [Chemical Formula 3] [Chemical Formula 4] [Chemical Formula 5] [Chemical Formula 6] [Chemical Formula 7] [Chemical Formula 8] [Chemical Formula 9] 5. The precursor compound of claim 1, wherein, The precursor compound for forming a thin film is a precursor for forming a thin film on a surface of a semiconductor substrate.

6. The precursor compound according to claim 5, wherein, The thickness of the film is or less.

7. The precursor compound of claim 5, wherein, The surface of the semiconductor substrate comprises silicon oxynitride or amorphous carbon. 8.A method of manufacturing a semiconductor device, comprising: preparing a substrate; forming a lower layer by depositing a precursor of Chemical Formula 1 on the substrate by an atomic layer deposition (ALD) method; and forming a photoresist layer on the lower layer [Chemical Formula 1] (In the Chemical Formula 1, R 0 is Si, Sn, Ge, Sb, In, Hf, Zr, Ti or Te, R 1 is CH3, CF3, CH=CH2, halogen or phenyl, R 2 and R 2 are each independently alkyl or alkoxy, R 3 is amine or halogen, R is hydrogen or halogen, and n is an integer of 1 to 7). 9.The method of claim 8, wherein: forming the lower layer comprises supplying the precursor comprising Chemical Formula 1 and supplying a purge gas, and the supply of the precursor and the supply of the purge gas are defined as one cycle, and the cycle is repeated at least once.

10. The method of claim 8, wherein, The formation of the lower layer is performed at a temperature of 100℃ to 250℃.

11. The method of claim 8, wherein, A surface of the substrate comprises silicon oxynitride or amorphous carbon.

12. The method of claim 8, wherein, The thickness of the lower layer is or less.

13. The method of claim 8, wherein, The precursor is any one of materials shown in the following Chemical Formula 2 to Chemical Formula 9: [Chemical Formula 2] [Chemical Formula 3] [Chemical Formula 4] [Chemical Formula 5] [Chemical Formula 6] [Chemical Formula 7] [Chemical Formula 8] [Chemical Formula 9]

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