Precursor compound for thin film formation and method for manufacturing a semiconductor device using the same

Abstract

This technology provides a precursor compound for thin film formation containing chemical formula 1 and a method for producing the same, which can prevent pattern collapse of the photoresist layer by shortening the exposure time for pattern formation and minimizing or eliminating the thickness of the lower layer having an etching selectivity ratio similar to that of the photoresist during post-exposure etching (in the chemical formula 1, R 0 is Si, Sn, Ge, Sb, In, Hf, Zr, Ti or Te, and R 1 R is CH3, CF3, CH=CH2, halogen or phenyl, 2 and R 2’ Each is independently an alkyl or alkoxy, and R 3 (where is an amine or halogen, R is hydrogen or halogen, and n is an integer between 1 and 7).

Description

[Technical Field]

[0001] The present invention relates to a precursor compound for thin film formation and a method for manufacturing a semiconductor device, and more particularly to a precursor compound for a lower layer formed below a photoresist layer and a method for manufacturing a semiconductor device using the same. [Background technology]

[0002] Photolithography is a technique that uses a photoresist (hereinafter referred to as "resist") on a substrate to expose it to a light source to form high-resolution circuits within semiconductor devices.

[0003] The lithography technique using the aforementioned resist can usually be performed in the following manner.

[0004] First, a resist composition containing a polymer matrix, a photoacid generator, a solvent, and other additives that can improve performance is spin-coated onto a silicon wafer and then cured to form a resist film. Next, the formed resist film is exposed to a light source in a pattern-wise manner and selectively heated to bring about a post-exposure bake (PEB) chemical transformation. When such a chemical transformation creates a difference in solubility between the exposed and unexposed regions of the resist film, a development process using a solvent is performed to generate a resist pattern image on the wafer. In the exposure process, radiation with wavelengths ranging from near ultraviolet (UV) to deep ultraviolet (DUV) and extreme ultraviolet (EUV) is typically used as the light source.

[0005] In such lithography processes, a laminate consisting of a substrate, a base layer, and a photoresist layer is generally used. To form a pattern on the laminate, the base layer is selectively etched during post-exposure etching. However, in actual process applications, the surface photoresist layer is also etched during post-exposure etching, resulting in a poor pattern shape and a decrease in the performance of the semiconductor device. [Overview of the project] [Problems that the invention aims to solve]

[0006] The embodiments of the present invention provide a precursor compound for thin film formation and a method for producing the same, which can prevent pattern collapse of the photoresist layer by shortening the exposure time for pattern formation and by minimizing or omitting the thickness of the lower layer having an etching selectivity ratio similar to that of the photoresist during post-exposure etching. [Means for solving the problem]

[0007] The thin-film formation precursor compound according to the embodiment of the present invention may be a thin-film formation precursor compound containing a substance of chemical formula 1;

[0008] TIFF2026513140000002.tif29170[Chemical formula 1] (In the above chemical formula 1, R 0 is Si, Sn, Ge, Sb, In, Hf, Zr, Ti or Te, and R 1 R is CH3, CF3, CH=CH2, halogen or phenyl, 2 and R 2’ Each of these is independently an alkyl group or an alkoxy group, and R 3 (where is an amine or halogen, R is hydrogen or halogen, and n is an integer between 1 and 7).

[0009] Preferably, the R of chemical formula 1. 0 is Si or Sn, and R 1 is CF3 or I, and R2 and R 2’ are each independently CH3, C2H5, C3H7, OCH3, OC2H5, and R 3 is N(CH3)2, N[(CH2)CH3]2, and R may be H. At this time, n in the chemical formula 1 may be an integer from 1 to 4.

[0010] The method for manufacturing a semiconductor device according to an embodiment of the present invention includes a step of preparing a substrate, a step of preparing a precursor containing a substance of chemical formula 1, which is a substance for forming a lower layer, and a step of depositing a precursor containing a substance of chemical formula 1 on the substrate by an atomic layer deposition (ALD) method to form a lower layer, and a step of forming a photoresist layer on the lower layer.

[0011] The step of forming the lower layer includes a step of supplying a precursor containing the substance of chemical formula 1 and a step of supplying a purge gas. A cycle defined by a step of supplying a precursor and a step of supplying a purge gas may be repeated at least once or more.

Advantages of the Invention

[0012] This technology can prevent pattern collapse of the photoresist layer by shortening the exposure time for pattern formation and minimizing or omitting the thickness of the lower layer having an etching selectivity similar to that of the photoresist during post-exposure etching.

[0013] In addition, the lower layer can sufficiently secure the adhesive force between the photoresist layer and the substrate and can be formed into an ultra-thin film of 10 Å or less.

Brief Description of the Drawings

[0014] [Figure 1] It is a diagram schematically showing the stacked structure of the semiconductor device 100 according to this embodiment. [Figure 2] It is a process flowchart for explaining the method for manufacturing a semiconductor device of this embodiment. [Figure 3] FIG. is a diagram schematically showing the deposition process of a precursor according to an embodiment.

BEST MODE FOR CARRYING OUT THE INVENTION

[0015] The terms and words used in this specification and the claims should not be construed as being limited to their ordinary or dictionary meanings. In accordance with the principle that the inventor can appropriately define the concept of the terms in order to explain his invention in the best way, they must be construed in a meaning and concept consistent with the technical idea of this embodiment.

[0016] The terms used in this specification are merely used to explain exemplary embodiments and are not intended to limit this embodiment. Singular expressions include plural expressions unless the context clearly indicates otherwise.

[0017] In each step, the identification codes are used for convenience of explanation, and the identification codes do not explain the order of each step. Unless each step clearly describes a specific order in the context, it may be implemented in a different order from the specified order. That is, each step may be implemented in the same order as the specified order, may be implemented substantially simultaneously, or may be implemented in the reverse order.

[0018] In this specification, terms such as "including", "comprising", or "having" are intended to specify the existence of implemented features, numbers, steps, components, or combinations thereof, and it should be understood that they do not preclude the possibility of the existence or addition of one or more other features, numbers, steps, components, or combinations thereof in advance.

[0019] The atomic layer deposition (ALD) process may be carried out as a single cycle consisting of a. source gas injection, b. purging, c. reaction gas injection, and d. purging, or as a half atomic layer deposition process consisting of two steps: a'. gas injection and b'. purging. Within this specification, "atomic layer deposition process using a precursor compound of chemical formula 1" may be carried out as such a half atomic layer deposition process.

[0020] Referring to Figure 1, this embodiment relates to a precursor compound for thin film formation and a method for producing the same. More specifically, the precursor compound for thin film formation is formed on a substrate 110 and can form a lower layer 120 that is formed below the photoresist layer 130.

[0021] The precursor compound for thin film formation according to this embodiment may be represented by chemical formula 1;

[0022] TIFF2026513140000003.tif29170[Chemical formula 1] (In the above chemical formula 1, R 0 is Si, Sn, Ge, Sb, In, Hf, Zr, Ti or Te, and R 1 R is CH3, CF3, CH=CH2, halogen or phenyl, 2 and R 2’ Each of these is independently an alkyl group or an alkoxy group, and R 3 (where is an amine or halogen, R is hydrogen or halogen, and n is an integer between 1 and 7).

[0023] As a precursor containing the above chemical formula 1, preferably, R 0 is Si or Sn, and R 1 is CF3 or I, and R 2 and R 2’ Each of these is independently CH3, C2H5, C3H7, OCH3, or OC2H5, and R 3 Compounds can be used where is N(CH3)2 or N[(CH2)CH3]2, R is H, and n is an integer from 1 to 4.

[0024] Among the precursors containing the aforementioned chemical formula 1, the precursors represented by the following chemical formulas 2 to 9 are applicable as examples.

[0025] TIFF2026513140000004.tif29170[Chemical formula 2]

[0026] TIFF2026513140000005.tif25170[Chemical formula 3]

[0027] TIFF2026513140000006.tif25170[Chemical formula 4]

[0028] TIFF2026513140000007.tif28170[Chemical formula 5]

[0029] TIFF2026513140000008.tif28170[Chemical formula 6]

[0030] TIFF2026513140000009.tif24170[Chemical formula 7]

[0031] TIFF2026513140000010.tif26170[Chemical formula 8]

[0032] TIFF2026513140000011.tif30170[Chemical formula 9]

[0033] 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. One end has a hydrophobic group such as an alkyl or olefin formed on it, and the other end has an amine group or a halogen group formed on it, so that one end can bond with the photoresist layer 130 and the other end can bond with the substrate 110.

[0034] Specifically, a linear carbon chain, such as alkyl or olefin, is formed at one end of the precursor material represented by chemical formula 1, thereby improving the bonding strength through improved van der Waals forces and through physical entanglement between the linear carbon chain and the photoresist layer 130. This improves surface deposition coverage by forming a self-assembling monolayer and enhances the bonding strength with the photoresist layer 130. In addition, R 1 The introduction of these functional groups improves the dipole moment, further enhancing the bonding strength with the hydrophobic photoresist layer 130.

[0035] In particular, R 1 In the case of CF3, the hydrophobicity is further increased, the bonding strength with the photoresist layer 130 is further improved, and the absorbance to the EUV light source is excellent during exposure for pattern formation, so the amount of EUV irradiation required to form the pattern can be reduced.

[0036] Furthermore, if a halogen substance is included as a functional group, the amount of EUV irradiation can be reduced due to the excellent light absorption efficiency of the halogen substance itself.

[0037] Figure 2 is a process flowchart illustrating the manufacturing method of the semiconductor device according to this embodiment. The manufacturing method of the semiconductor device according to this embodiment will be explained with reference to Figure 2. For the sake of explanation, Figure 1 shows the semiconductor device manufactured according to this embodiment.

[0038] First, Figure 1 is a schematic diagram showing the stacked structure of the semiconductor device 100 manufactured by the semiconductor device manufacturing method of this embodiment.

[0039] A semiconductor device 100 manufactured by the semiconductor device manufacturing method of this embodiment includes a substrate 110, a lower layer 120 formed by depositing a precursor of chemical formula 1 onto the substrate 110, and a photoresist layer 130 formed on the lower layer 120;

[0040] TIFF2026513140000012.tif29170[Chemical formula 1] (In the above chemical formula 1, R 0 is Si, Sn, Ge, Sb, In, Hf, Zr, Ti or Te, and R 1 R is CH3, CF3, CH=CH2, halogen or phenyl, 2 and R 2’ Each of these is independently an alkyl group or an alkoxy group, and R 3 (where is an amine or halogen, R is hydrogen or halogen, and n is an integer between 1 and 7).

[0041] Since the precursor containing the aforementioned chemical formula 1 is the same as that described earlier, a redundant explanation will be omitted.

[0042] The substrate 110 is capable of forming elements, circuits, or films, and includes a base substrate 111 and a surface film 112. The base substrate 111 may be formed from a group IV material such as silicon or germanium, or from a compound such as a group III-V material such as GsAs, GaN, InP, or InGaN, a group II-VI material such as ZnSe, or a group IV-IV material such as SiC or SiGe.

[0043] The surface of the substrate 110 may contain silicon oxynitride (SiON) or amorphous carbon. Specifically, the substrate may have a surface film 112 formed on its surface that contains silicon oxynitride or amorphous carbon. For example, the substrate 110 may have a silicon oxynitride film or an amorphous carbon film as the surface film 112 on its surface.

[0044] Thus, the substrate 110 containing silicon oxynitride or amorphous carbon on its surface has hydrophilic properties, so when the precursor represented by chemical formula 1 contains an amine group, it can form a strong bond with the substrate 110, and a film can be easily formed by depositing the precursor represented by chemical formula 1 onto the substrate 110.

[0045] The lower layer 120 may be formed by an atomic layer deposition process or a half atomic layer deposition process.

[0046] A precursor represented by chemical formula 1 can be deposited onto the substrate 110 by an atomic layer deposition process to form a lower layer 120, and the thickness of the lower layer 120 may be 10 Å or less, or 1 to 10 Å.

[0047] Conventionally, the lower layer 120 is formed by a spin coating method and is formed to a thickness of 50 Å or more. However, in this case, the minimum amount of light irradiation required for semiconductor pattern formation is large, and the etching time is long. Therefore, only the lower layer 120 must be selectively etched during the pattern formation process, but the photoresist layer 130 is also etched, resulting in the problem of pattern collapse.

[0048] In this embodiment, the semiconductor device 100 forms the lower layer 120 using an atomic layer deposition method, making it possible to form a lower layer 120 with a thickness of 10 Å or less. When the lower layer 120 is realized in an ultrathin film form, the amount of light irradiation for pattern formation can be reduced, shortening the etching time, and thus the pattern can be formed without damaging the photoresist layer 130. In addition, it is possible to reduce the amount of etching solution used during etching, thereby reducing the costs associated with the process.

[0049] The atomic layer deposition method may first include the steps of vaporizing a liquid precursor represented by chemical formula 1, depositing it onto a substrate 110, and purging, and the deposition and purging may be repeated multiple times as one cycle.

[0050] At this time, when transporting the vaporized precursor of chemical formula 1, inert gases such as argon (Ar), nitrogen (N2), and helium (He) can be used as carrier gases, but are not limited to these. Similarly, the purge gas used in the purge step can also be the inert gases mentioned above, but are not limited to these.

[0051] The photoresist layer 130 formed on the lower layer 120 may include at least one of CAR (Chemical amplified Resist) Type and MOR (Metal Oxide Resist) Type.

[0052] Figure 2 is a process flowchart illustrating the manufacturing method of the semiconductor device 100 in this embodiment. The manufacturing method of the semiconductor device 100 in this embodiment will be explained with reference to Figure 2.

[0053] This embodiment includes a method for manufacturing a semiconductor device 100, comprising the steps of: preparing a substrate 110 (S10); preparing a precursor of chemical formula 1, which is a material for forming a lower layer 120 (S20); forming a lower layer 120 by depositing the precursor of chemical formula 1 onto the substrate 110 using an atomic layer deposition (ALD) method (S30); and forming a photoresist layer 130 on the lower layer 120 (S40).

[0054] The precursor represented by chemical formula 1 is the same as the one described earlier, so a redundant explanation will be omitted.

[0055] Step S10 is a step of preparing the substrate 110, and may also be a step of placing the substrate 110 into the reaction chamber.

[0056] The substrate 110 is on which elements, circuits, or films are formed, and includes a base substrate 111 and a surface film 112. The base substrate 111 may be formed of a group IV material such as silicon or germanium, or of a compound such as a group III-V material such as GsAs, GaN, InP, or InGaN, a group II-VI material such as ZnSe, or a group IV-IV material such as SiC or SiGe.

[0057] The surface of the substrate 110 may contain silicon oxynitride or amorphous carbon. Specifically, the substrate may have a surface film 112 formed on its surface that contains silicon oxynitride or amorphous carbon. For example, the substrate 110 may have a silicon oxynitride film or an amorphous carbon film as the surface film 112 on its surface.

[0058] Step S20 is a step of preparing a precursor containing chemical formula 1, which is a material for forming the lower layer 120. Since the precursor containing chemical formula 1 exists in liquid form at room temperature, in this step the precursor can be vaporized by a vaporizer for application to the atomic layer deposition (ALD) method.

[0059] Step S30 is a step of supplying a precursor containing chemical formula 1 to the chamber and reacting it to form the lower layer 120, and the steps of supplying the precursor containing chemical formula 1 in step S31 and supplying the purge gas in step S32 may be considered as one cycle, and at least one cycle may be repeated. This step may be carried out in a temperature range of 100 to 250°C, and R 0 ~R 3 Since each type of precursor defined by the method has a different decomposition temperature, it is preferable to carry out the decomposition at a temperature below the decomposition temperature of the precursor.

[0060] In step S31, the vaporized precursor containing chemical formula 1 is supplied in gaseous form to the chamber containing the substrate 110. At this time, an inert gas such as argon (Ar), nitrogen (N2), and helium (He) may be supplied to the chamber as a carrier gas along with the vaporized precursor containing chemical formula 1.

[0061] The amine group formed at one end of the precursor supplied to the chamber containing the substrate 110 has hydrophilic properties, and can therefore bond with the hydrophilic silicon oxynitride or amorphous carbon on the surface of the substrate 110, allowing it to be deposited as a thin film on the surface of the substrate 110. Specifically, the amine group of the precursor containing chemical formula 1 is degassed at high temperature to form a reaction portion, which then bonds with nucleophilic hydroxyl groups, amino groups, or sp2 carbon bonds on the surface of the substrate 110 to form a single film (monolayer) arranged in a line. This series of processes can be understood more clearly by looking at Figure 3.

[0062] Figure 3 shows an example of the deposition process of a precursor containing chemical formula 1 according to one embodiment. In the embodiment shown in Figure 3, the example will be explained using a precursor in which R is H, represented by chemical formula 1.

[0063] First, when the precursor of chemical formula 1 is exposed to heat, the nucleophile hydroxyl group, amino group, or unsaturated bond of the surface film 112, which is the surface of the substrate 110, interacts with the precursor's R 0 They combine, R 3 The molecules separate, allowing the precursor containing chemical formula 1 to bond in a single line to the surface of the surface film 112, thereby forming a single film.

[0064] On the other hand, step S32 is performed to purge the unreacted reactants from the previous step and by-products, including gaseous products generated by the reaction, and may be done by supplying an inert gas into the chamber. In this case, the inert gas can be, but is not limited to, argon (Ar), nitrogen (N2), and helium (He).

[0065] Step S40 is a step of forming a photoresist layer 130 on the lower layer 120, and may be a step of forming the photoresist layer 130 on the lower layer 120 using an atomic layer deposition method, in which case the photoresist layer 130 may be formed of or include at least one of CAR (Chemical amplified Resist) type and MOR (Metal Oxide Resist) type materials.

[0066] As explained earlier, the lower layer 120 is formed as a single film in which precursors containing chemical formula 1 are arranged in a single line. At this time, the hydrophilic portion is located on the substrate 110 side, and the hydrophobic portion of the alkyl or olefin carbon chain structure is located on the opposite side. When the lower layer 120 is deposited on the substrate 110 during the lower layer formation step, the surface of the lower layer 120 exposed to the outside exhibits hydrophobic characteristics. Therefore, when a photoresist layer 130 is formed on the surface of the hydrophobic lower layer 120 using a photoresist material, van der Waals forces act between the surface of the hydrophobic lower layer 120 and the hydrophobic photoresist layer 130, forming a strong bonding force. The carbon chain structure of the precursor containing chemical formula 1 can then intertwine with the photoresist layer 130 to form an additional bonding force. In particular, the R of the precursor of chemical formula 1 1 When CF3 or a phenyl group is used, the bonding strength with the photoresist layer is further improved, with CF3 exhibiting the best bonding strength.

[0067] In this embodiment, the semiconductor device 100 has an improved EUV absorption rate of the lower layer 120, which allows for a reduction in the amount of EUV irradiation required for pattern formation. Since the lower layer 120 is formed as a thin film of 10 Å or less by the atomic layer deposition process, the EUV exposure time and the time the photoresist layer 130 is exposed to the etching solution can be shortened, preventing damage to the photoresist layer 130 (pattern collapse). This enables a reduction in process costs and a reduction in process time through a reduction in irradiation amount, a reduction in the amount of etching solution used, and a reduction in pattern formation time.

[0068] Furthermore, when comparing the semiconductor device 100 of this embodiment with a comparative example semiconductor device 100 in which the lower layer 120 was formed by a normal spin coating process, the line width reduction (LWR) and the minimum critical dimension (CD) value at which the pattern is damaged are similar, but the dose to size (DtS) can be significantly reduced, and a reduction in DtS of approximately 3-30% was observed compared to the normal spin coating method.

[0069] Although one embodiment of the present invention has been described above, a person with ordinary skill in the art can modify and change the present invention in various ways by adding, changing, deleting, or adding components, without departing from the spirit of the invention as described in the claims, and this is also included within the scope of the rights of the present invention. [Industrial applicability]

[0070] The method for manufacturing a semiconductor device using the thin-film formation precursor compound according to the present invention has the effect of preventing pattern collapse of the photoresist layer by shortening the exposure time for pattern formation and minimizing or omitting the thickness of the lower layer, which has an etching selectivity ratio similar to that of the photoresist, during post-exposure etching. Therefore, it has industrial applicability.

Claims

1. A precursor compound for thin film formation containing the substance of chemical formula 1; [Chemical formula 1] (In the above chemical formula 1, R ０ is Si, Sn, Ge, Sb, In, Hf, Zr, Ti, or Te, and R １ CH ３ CF ３ ienCH=CH ２ , halogen or phenyl, R ２ and R ２’ Each of these is independently an alkyl group or an alkoxy group, and R ３ (where is an amine or halogen, R is hydrogen or halogen, and n is an integer from 1 to 7).

2. In the above Chemical Formula 1, R ０ is Si or Sn, R １ is CF ３ or I, R ２ and R ２’ are each independently CH ３ C ２ H ５ C ３ H ７ OCH ３ OC ２ H ５ and R ３ is N(CH ３ ) ２ N[(CH ２ )CH ３ ) ２ where R is H. The precursor compound for thin film formation according to Claim 1.

3. The precursor compound for thin film formation according to claim 2, wherein n in the chemical formula 1 is an integer from 1 to 4.

4. The thin film formation precursor compound according to claim 1, characterized in that the thin film formation precursor compound is one of the substances represented by the following chemical formulas 2 to 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 thin-film formation precursor compound according to claim 1, wherein the thin-film formation precursor compound is a precursor for forming a thin film on the surface of a semiconductor substrate.

6. The precursor compound for forming a thin film according to claim 5, wherein the thickness of the thin film is 10 Å or less.

7. The precursor compound for thin film formation according to claim 5, wherein the surface of the semiconductor substrate contains silicon oxynitride or amorphous carbon.

8. The steps include preparing the circuit board and The steps include: depositing a precursor of chemical formula 1 onto the substrate using an atomic layer deposition (ALD) method to form a lower layer; A method for manufacturing a semiconductor device, comprising the step of forming a photoresist layer on the lower layer; [Chemical formula 1] (In the above chemical formula 1, R ０ is Si, Sn, Ge, Sb, In, Hf, Zr, Ti, or Te, and R １ CH ３ CF ３ ienCH=CH ２ , halogen or phenyl, R ２ and R ２’ Each of these is independently an alkyl group or an alkoxy group, and R ３ (where is an amine or halogen, R is hydrogen or halogen, and n is an integer from 1 to 7).

9. The step of forming the lower layer is, The process includes the steps of supplying a precursor containing the aforementioned chemical formula 1 and supplying a purge gas. A method for manufacturing a semiconductor device according to claim 8, wherein a cycle in which the steps of supplying a precursor and supplying a purge gas are defined as one cycle is repeated at least once.

10. The method for manufacturing a semiconductor device according to claim 8, wherein the step of forming the lower layer is performed at a temperature of 100 to 250°C.

11. The method for manufacturing a semiconductor device according to claim 8, wherein the surface of the substrate contains silicon oxynitride or amorphous carbon.

12. The method for manufacturing a semiconductor device according to claim 8, wherein the thickness of the lower layer is 10 Å or less.

13. The method for manufacturing a semiconductor device according to claim 8, characterized in that the precursor is one of the substances represented by the following chemical formulas 2 to 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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