A film-forming composition containing a Group 4 metal element-containing precursor compound, and a method for forming a film using the same

Abstract

The present invention relates to a film-forming composition containing a Group 4 metal element-containing precursor compound, and a method for forming a Group 4 metal element-containing film using the same. The use of the film-forming composition containing the Group 4 metal element-containing precursor compound of the present invention achieves self-limiting film growth by atomic layer deposition (ALD) in a wide temperature range from low to high, enabling the formation of Group 4 metal element-containing films for various purposes at various process temperatures. In particular, according to the method for forming a Group 4 metal element-containing film of the present invention, the ALD film formation rate (GPC) is constant over a wide temperature range, and a Group 4 metal element-containing film of uniform thickness can be formed even on a surface having a groove with a large aspect ratio. Therefore, the above method can be advantageously used in the manufacture of various semiconductor devices such as DRAMs and 3D NAND flash memories.

Description

Technical Field

[0001] The present invention relates to a film-forming composition containing a Group 4 metal element-containing precursor compound and a method for forming a film using the same.

Background Art

[0002] Group 4 metal element-containing films, particularly Group 4 metal oxide films having a high dielectric constant, are essential thin films for operating non-memory semiconductor devices such as logic devices and memory semiconductor devices such as DRAM, flash memory, resistive memory (ReRAM), ferroelectric memory (FeRAM), and phase change memory (PCRAM).

[0003] In particular, such Group 4 metal element-containing films are used in state-of-the-art technologies of organic light-emitting diodes (OLEDs) in the display field and gate insulating films and capacitor high-k dielectric films of memory devices.

[0004] On the other hand, in the semiconductor field and non-semiconductor fields, products having complex shapes such as high aspect ratios and three-dimensional structures are being developed in various ways. As a result, there is a demand for a film-forming composition containing a Group 4 metal element-containing precursor compound for forming a Group 4 metal element-containing film that can be used for atomic layer deposition (ALD), is suitable for process temperatures in various application fields, and can overcome a high step ratio.

Prior Art Documents

Non-Patent Documents

[0005]

Non-Patent Document 1

Disclosure of the Invention

[0006] The technical problem to be solved by the present invention is to provide a method for forming a Group 4 metal element-containing film that can obtain a uniform film with excellent step coverage even on a surface having a complex shape, without changing the film formation rate (GPC), which is film growth for each ALD gas supply cycle, in a wide temperature range.

[0007] Another technical problem to be solved by the present invention is to provide a film-forming composition containing a Group 4 metal element-containing precursor compound having a specific structure.

[0008] However, the problems to be solved by the present invention are not limited to the above, and those skilled in the art will clearly understand other problems from the following description. Solutions to the problems

[0009] To achieve the above object, the present invention provides a method for forming a Group 4 metal element-containing film, including a step of reacting a film-forming composition containing a Group 4 metal element-containing precursor compound represented by the following formula 1 with a reaction gas to form a Group 4 metal element-containing film on a substrate.

[0010]

Chemical formula

[0011] In formula 1, M is Zr or Hf, R1 is a methyl group, R2 is selected from the group consisting of linear or branched C3-C4 alkyl groups, and R3 to R8 are each independently selected from the group consisting of linear or branched C1-C4 alkyl groups.

[0012] Furthermore, a film-forming composition containing the Group 4 metal element-containing precursor compound represented by the above formula 1 is provided. Advantageous effects of the invention

[0013] By using the film-forming composition containing the Group 4 metal element-containing precursor compound of the present invention, self-limiting film growth of ALD can be achieved in a wide temperature range, particularly at high temperatures. Therefore, it is possible to form Group 4 metal element-containing films for various applications at various process temperatures.

[0014] In particular, according to the method for forming the Group 4 metal element-containing film of the present invention, since GPC does not change in a wide temperature range from low temperature to high temperature, it is possible to form a Group 4 metal element-containing film with a uniform thickness even on a surface having grooves with a large aspect ratio. Therefore, it can be advantageously used for manufacturing various semiconductor devices such as DRAM and 3D NAND flash memories.

Brief Description of the Drawings

[0015]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Best Mode for Carrying Out the Invention

[0016] The present application is described in more detail below in this specification.

[0017] The advantages and features of the present invention and the methods for achieving them will become apparent with reference to the embodiments described below in this specification. However, the present invention is not limited to the embodiments described below and may be embodied in various different forms. These embodiments are provided so that the disclosure of the present invention will be thorough and complete, and will fully convey the scope of the present invention to those skilled in the art. The present invention is defined only by the claims.

[0018] Furthermore, in this specification, when it is mentioned that a certain component is formed "on" another component, it means not only that one component is directly formed "on" another component, but also that other component(s) may be interposed therebetween.

[0019] In this specification, when a certain part is referred to as "including" a component, it should be understood that, unless otherwise specified, that part does not exclude other components, but may also include other components.

[0020] All numerical values and expressions regarding the amounts of components, reaction conditions, etc. used in this specification should be understood to be modified by the term "about" unless otherwise specified.

[0021] In this specification, the terms "film" and "thin film" refer to both "film" and "thin film" unless otherwise specified.

[0022] As used herein, the term "alkyl" or "alkyl group" includes linear or branched alkyl groups and all possible isomers thereof. For example, the alkyl or alkyl group includes, but is not limited to, methyl group (Me), ethyl group (Et), normal propyl group ( n Pr), isopropyl group ( i Pr), normal butyl group ( n Bu), isobutyl group ( i Bu), tert-butyl group (tert-Bu, t Bu), sec-butyl group ( sec Bu), etc., as well as their isomers and the like.

[0023] [Method for Forming a Group 4 Metal Element-Containing Film] According to an embodiment of the present invention, there is provided a method for forming a group 4 metal element-containing film, which includes reacting a film-forming composition containing a group 4 metal element-containing precursor compound represented by the following formula 1 with a reaction gas to form a group 4 metal element-containing film on a substrate.

[0024] [Chemical Formula]

[0025] In formula 1, M is Zr or Hf, R1 is a methyl group, R2 is selected from the group consisting of linear or branched C3-C4 alkyl groups, and R3-R8 are each independently selected from the group consisting of linear or branched C1-C4 alkyl groups.

[0026] In the method for forming a group 4 metal element-containing film according to an embodiment of the present invention, since a film-forming composition containing a group 4 metal element-containing precursor compound represented by the above formula 1 is used, it is possible to form a group 4 metal element-containing film by chemical vapor deposition (CVD) or ALD with a certain GPC in a wide temperature range including both high and low temperatures.

[0027] In particular, the Group 4 metal element-containing precursor compound represented by Formula 1 may have a structure of a single composition. Here, the term "single composition" refers to a substance that does not include structural isomers. It does not necessarily mean a 100% pure substance. For example, it may contain impurities of 5% or less. Further, the term "impurities" may refer to all substances other than the Group 4 metal element-containing precursor compound represented by Formula 1.

[0028] Specifically, the Group 4 metal element-containing precursor compound represented by Formula 1 1 When analyzed by an H-NMR spectrum, it may have a structure of a single composition (single substance structure) that does not include structural isomers or a mixture thereof, and the content of impurities is, for example, 5% or less, 3% or less, 2% or less, 1% or less, or 0.5% or less. Therefore, the Group 4 metal element-containing precursor compound represented by Formula 1 has a high purity of 95% or more, exists in a liquid state advantageous for the preparation process at room temperature, and has excellent thermal stability, so that various Group 4 metal element-containing films can be easily formed.

[0029] Furthermore, it is possible to form a uniform film with excellent coverage on a substrate having a pattern (groove) on its surface, a porous substrate, a plastic substrate, or a substrate having a complex shape in a three-dimensional structure, thereby providing a high-quality Group 4 metal element-containing film. Therefore, it has technical significance in that it can be advantageously used for various applications in the field of semiconductor devices, and in that it can exhibit excellent characteristics.

[0030] Specifically, according to an embodiment of the present invention, when a film-forming composition containing a Group 4 metal element-containing precursor compound is used to form a Group 4 metal element-containing film, specifically, a zirconium (Zr)-containing film or a hafnium (Hf)-containing film, for example, at a temperature of 150°C to 500°C, 200°C to 500°C, 200°C to 450°C, 250°C to 450°C, 250°C to 400°C, 250°C to 380°C, 250°C to 360°C, 250°C to 350°C, or 250°C to 340°C by ALD, the change rate of GPC (ΔGPC, %) is close to zero or, for example, 30% or less, less than 30%, 29% or less, 25% or less, 20% or less, 18% or less, 16% or less, 15% or less, 13% or less, 12% or less, 11% or less, less than 11%, 10% or less, 9% or less, 8% or less, 7% or less, 6% or less, 5% or less, or 4% or less and is small.

[0031] The Group 4 metal element-containing precursor compound represented by Formula 1 will be described in detail in the column of "film-forming composition" below.

[0032] The method for forming a Group 4 metal element-containing film according to an embodiment of the present invention includes a step of preparing at least a part of a substrate in a reaction chamber (first step), a step of supplying a gaseous film-forming composition to the reaction chamber (second step), and a step of supplying a reaction gas to the reaction chamber (third step).

[0033] Furthermore, according to the method for forming a Group 4 metal element-containing film, the gas supply cycle including the second step and the third step can be repeated a plurality of times, for example, several times, dozens of times, hundreds of times, or thousands of times to form a Group 4 metal element-containing film having a desired thickness.

[0034] Furthermore, between the second step and the third step, a step of supplying an inert gas such as argon (Ar) gas or nitrogen (N2) gas to the reaction chamber to remove the film-forming composition (gas) remaining in the reaction chamber may be further included. Further, after the third step, a step of supplying an inert gas such as argon (Ar) gas or nitrogen (N2) gas to the reaction chamber to remove the reaction gas remaining in the reaction chamber may be further included.

[0035] Specifically, the method for forming a Group 4 metal element-containing film may include a step (first step) of preparing at least a part of a substrate in a reaction chamber.

[0036] The substrate may be one selected from a conventional semiconductor wafer, a compound semiconductor wafer, and plastic substrates (PI, PET, PES, and PEN), but is not limited thereto. Further, a substrate having holes or grooves may be used, or a porous substrate having a large surface area may be used.

[0037] In particular, for example, a Group 4 metal element-containing film having a uniform thickness of several nanometers (nm) to several micrometers (μm) can be formed on a substrate having a pattern (groove) on its surface, a porous substrate, or a plastic substrate in various temperature ranges of 150°C to 500°C. On the substrate, there is an excellent effect that a uniform Group 4 metal element-containing film can be formed on the deepest surface and the upper surface of at least one fine pattern (groove) having an aspect ratio of 1 or more, for example, about 1 to 50 or more, and a width of 1 μm or less, for example, about 1 μm to 10 nm or less.

[0038] The method for forming a Group 4 metal element-containing film may include a step (second step) of supplying a film-forming composition containing a Group 4 metal element-containing precursor compound in a gaseous state to the reaction chamber.

[0039] The film-forming composition containing a Group 4 metal element precursor compound is supplied in a gaseous state to form a Group 4 metal element-containing oxide film on a substrate. Further, a film-forming composition containing other components can be used together with the film-forming composition to form a Group 4 metal element-containing composite metal oxide film or a nano-laminated film, for example, a film of Zr—Si—O, Hf—Si—O, Hf—Zr—O, ZrO2 / Al2O3 / ZrO2, or ZrO2 / Al2O3 / TiO2.

[0040] Specifically, when the film-forming composition containing a Group 4 metal element-containing precursor compound is supplied to a reaction chamber, the film-forming composition containing a Group 4 metal element-containing precursor compound is supplied onto the substrate using a carrier gas or a dilution gas, and a Group 4 metal element-containing film can be formed at a process temperature of 150° C. to 500° C.

[0041] Furthermore, it is preferable to use a single gas or a mixed gas selected from the group consisting of argon (Ar), nitrogen (N2), helium (He), and hydrogen (H2) as the carrier gas or the dilution gas.

[0042] Furthermore, the method of supplying the film-forming composition containing a Group 4 metal element-containing precursor compound to a reaction chamber may be at least one method selected from the group consisting of a bubbling method in which the film-forming composition containing a Group 4 metal element-containing precursor compound is forcibly vaporized using a carrier gas or a dilution gas, a liquid supply system (LDS) method in which the composition is supplied in a liquid phase at room temperature and vaporized through a vaporizer, a vaporization flow control (VFC) method in which the film-forming composition containing the precursor compound is directly supplied using its vapor pressure, and a bypass method. Further, the method of supplying a gaseous film-forming composition in chemical vapor deposition (CVD) or atomic layer deposition (ALD) can be applied to the present invention.

[0043] The method for forming a Group 4 metal element-containing film according to an embodiment of the present invention may include a step of supplying a reaction gas to a reaction chamber (step 3).

[0044] According to the method for forming a Group 4 metal element-containing film, in order to deposit a Group 4 metal element-containing oxide film (ZrO2, HfO2) or a Group 4 metal element-containing composite metal oxide film (ZrSiO x , ZrAlO x , ZrHfO x , ZrHfSiO x , ZrHfAlO x , ZrHfSiAlO x , ZrON, etc.), at least one selected from the group consisting of water vapor (H2O), oxygen (O2), oxygen plasma (O2 plasma), nitrogen oxides (NO, N2O), nitrogen oxide plasma (N2O plasma), oxygen nitrate (N2O2), hydrogen peroxide (H2O2), and ozone (O3) can be used as a reaction gas.

[0045] Furthermore, in order to deposit a Group 4 metal element-containing nitride film or a Group 4 metal element-containing composite metal nitride film, at least one selected from the group consisting of ammonia (NH3), ammonia plasma (NH3 plasma), hydrazine (N2H4), and nitrogen plasma (N2 plasma) may be used during film formation.

[0046] According to an embodiment of the present invention, the film-forming composition containing a Group 4 metal element-containing precursor compound is supplied in a gaseous state, and forms at least one selected from the group consisting of a Group 4 metal element-containing nitride film, a Group 4 metal element-containing carbide film, and a Group 4 metal element-containing composite metal film on a substrate.

[0047] For example, the film-forming composition containing a Group 4 metal element-containing precursor compound is supplied in a gaseous state, and forms a Group 4 metal element-containing film, particularly a Group 4 metal element-containing oxide film, a Group 4 metal element-containing composite metal oxide film, a Group 4 metal element-containing nitride film, or a Group 4 metal element-containing composite metal nitride film on at least a part of the surface of the substrate by CVD or ALD.

[0048] The method for forming a Group 4 metal element-containing film may use any method and / or apparatus known in the relevant field to which the present invention pertains, and may be carried out using one or more additional reaction gases or the like as necessary.

[0049] The method for forming a Group 4 metal element-containing film may be carried out by CVD, for example, metalorganic chemical vapor deposition (MOCVD), or may be implemented by ALD. MOCVD or ALD may be carried out using a film-forming apparatus, film-forming conditions, and reaction gases known in the relevant field.

[0050] [Group 4 metal element-containing film] According to an embodiment of the present invention, a Group 4 metal element-containing film formed by a method for forming a Group 4 metal element-containing film is provided.

[0051] The Group 4 metal element-containing film may have a thickness of about 1 nanometer (nm) to several micrometers (μm), and may be variously applied according to the intended use. Specifically, the Group 4 metal element-containing film may be formed in a thickness range of 1 nm to 500 nm.

[0052] The Group 4 metal element-containing film may be formed on a substrate (or circuit board).

[0053] The substrate is as described above.

[0054] The Group 4 metal element-containing film according to an embodiment of the present invention becomes a high-quality one having stable and consistent physical properties and excellent step coverage by forming a film using a composition containing a Group 4 metal element-containing precursor compound having a specific structure.

[0055] The Group 4 metal element-containing film may be at least one selected from the group consisting of a Group 4 metal element-containing oxide film, a Group 4 metal element-containing composite metal oxide film, a Group 4 metal element-containing nitride film, and a Group 4 metal element-containing composite metal nitride film. Specifically, the Group 4 metal element-containing film may include at least one selected from the group consisting of a Group 4 metal element-containing oxide film and a Group 4 metal element-containing composite metal oxide film.

[0056] Furthermore, the Group 4 metal element-containing film may include, for example, a nano-laminated film of Zr—Si—O, Hf—Si—O, Hf—Zr—O, ZrO2 / Al2O3 / ZrO2, or ZrO2 / Al2O3 / TiO2.

[0057] Furthermore, the Group 4 metal element-containing film can have extremely excellent step coverage.

[0058] For example, when an oxide film or a nitride film having a thickness of about 5 nm to 20 nm is formed in a groove having an aspect ratio of 10:1 or more by ALD at a process temperature of about 300° C. or higher using the film-forming composition according to an embodiment of the present invention, the thickness deviation calculated by measuring the film thicknesses at the upper, central, and lower portions is extremely small, indicating extremely excellent step coverage (%). In this case, the step coverage refers to the ratio of the lower thickness to the upper thickness ((lower thickness / upper thickness)×100).

[0059] Specifically, the film-forming composition according to an embodiment of the present invention can have a step coverage of 80% or more, 82% or more, 85% or more, 90% or more, 92% or more, 93% or more, 95% or more, or 96% or more.

[0060] In particular, when forming an oxide film or a nitride film in a groove having a large aspect ratio, it is difficult to form a film having a constant thickness because the thickness deviation of the film formed from the upper portion to the lower portion is large. However, the film-forming composition according to an embodiment of the present invention can form a film having a uniform thickness even in a groove having a large aspect ratio. Therefore, it is more effective when manufacturing various semiconductor devices such as DRAM and 3D NAND flash memory.

[0061] More specifically, when a hafnium (Hf)-containing oxide film having a thickness of about 6 to 7 nm is formed on a substrate on which a titanium nitride (TiN) film is formed in a groove having an aspect ratio of 11:1 by ALD at process temperatures of about 350 °C and about 400 °C using the film-forming composition according to an embodiment of the present invention, the step coverage rate (%) calculated by measuring the thickness of the hafnium (Hf)-containing oxide film in the transmission electron microscope (TEM) photographs of the upper, central, and lower portions of the groove shown in FIG. 6 can be extremely excellent and not less than a specific value.

[0062] According to one embodiment, when a Group 4 metal element-containing film is formed on a substrate having an aspect ratio of 11:1 at a temperature of about 350 °C, the Group 4 metal element-containing film, for example, a hafnium (Hf)-containing oxide film, may have a step coverage rate (%) of, for example, 80% or more, 82% or more, 85% or more, 90% or more, 92% or more, 93% or more, 95% or more, or 96% or more.

[0063] Furthermore, when a Group 4 metal element-containing film is formed on a substrate having an aspect ratio of 11:1 at a temperature of about 400 °C, the Group 4 metal element-containing film, for example, a hafnium (Hf)-containing oxide film, may have a step coverage rate (%) of, for example, 85% or more, 90% or more, 92% or more, 93% or more, 95% or more, 96% or more, 97% or more, or 98% or more.

[0064] Furthermore, when a zirconium (Zr)-containing oxide film having a thickness of about 12 to 15 nm is formed on a substrate on which a silicon oxide film is formed in a groove having an aspect ratio of 20:1 by ALD at process temperatures of about 340 °C and about 360 °C using the film-forming composition according to an embodiment of the present invention, the step coverage rate (%) calculated by measuring the thickness of the zirconium (Zr)-containing oxide film in the transmission electron microscope (TEM) photographs of the upper, central, and lower portions of the groove shown in FIGS. 4 and 5 can be extremely excellent and not less than a specific value.

[0065] According to one embodiment, when forming a Group 4 metal element-containing film on a substrate having an aspect ratio of 20:1 at a temperature of about 300°C, the Group 4 metal element-containing film, for example, a zirconium (Zr)-containing oxide film, may have a step coverage rate (%) of, for example, 80% or more, 82% or more, 85% or more, 90% or more, 92% or more, 93% or more, 95% or more, or 96% or more.

[0066] Furthermore, when forming a Group 4 metal element-containing film on a substrate having an aspect ratio of 20:1 at a temperature of about 340°C, the Group 4 metal element-containing film, for example, a zirconium (Zr)-containing oxide film, may have a step coverage rate (%) of, for example, 80% or more, 82% or more, 85% or more, 90% or more, 92% or more, 93% or more, 95% or more, or 96% or more.

[0067] Furthermore, when forming a Group 4 metal element-containing film on a substrate having an aspect ratio of 20:1 at a temperature of about 360°C, the Group 4 metal element-containing film, for example, a zirconium (Zr)-containing oxide film, may have a step coverage rate (%) of, for example, 85% or more, 90% or more, 92% or more, 93% or more, 95% or more, 96% or more, 97% or more, 98% or more, or 99% or more.

[0068] When the Group 4 metal element-containing film has a step coverage rate (%) that satisfies the above range, high step ratios and fine thickness control become possible, and it can be advantageously used for manufacturing various semiconductor devices such as DRAM and 3D NAND flash memories.

[0069] [Composition for film formation] The composition for film formation according to an embodiment of the present invention may contain a Group 4 metal element-containing precursor compound represented by the following formula 1.

[0070] [Chemical formula]

[0071] In Formula 1, M is Zr or Hf, R1 is a methyl group, R2 is selected from the group consisting of linear or branched C3-C4 alkyl groups, and R3-R8 are each independently selected from the group consisting of linear or branched C1-C4 alkyl groups.

[0072] Since the film-forming composition according to the embodiment of the present invention contains the compound represented by Formula 1, for example, when forming a film at a process temperature in a wide temperature range such as 250°C to 400°C, the change rate of GPC (ΔGPC, %) with respect to the temperature represented by the following Formula A may be as small as 30% or less, less than 30%, 25% or less, 20% or less, 18% or less, 15% or less, 13% or less, 12% or less, 11% or less, less than 11%, 10% or less, 8% or less, 7% or less, 6% or less, or 5% or less.

[0073]

Number

[0074] In Formula A, GPC 250 is the GPC at 250°C, and GPC temp is the GPC at the process temperature.

[0075] Specifically, according to the embodiment of the present invention, when forming a film at a process temperature of 250°C to 320°C using the film-forming composition, for example, the change rate of GPC (ΔGPC, %) with respect to the temperature may be as small as 30% or less, less than 30%, 25% or less, 20% or less, 10% or less, 8% or less, 7% or less, 6% or less, 5% or less, 4% or less, 3% or less, 2% or less, 1.5% or less, or 1% or less.

[0076] According to another embodiment of the present invention, when forming a film at a process temperature of 250°C to 340°C using the film-forming composition, for example, the change rate of GPC (ΔGPC, %) with respect to the temperature may be as small as 30% or less, less than 30%, 25% or less, 20% or less, less than 20%, 18% or less, 15% or less, 13% or less, 12% or less, 11% or less, less than 11%, 10% or less, 8% or less, 7% or less, or 6% or less.

[0077] According to another embodiment of the present invention, when forming a film using the film-forming composition at a process temperature of, for example, 250°C to 360°C, the rate of change of GPC with respect to temperature (ΔGPC, %) may be as small as, for example, 30% or less, less than 30%, 25% or less, 20% or less, 18% or less, 15% or less, 13% or less, 12% or less, 11% or less, less than 11%, 10% or less, or 9% or less.

[0078] According to another embodiment of the present invention, when forming a film using the film-forming composition at a process temperature of, for example, 250°C to 380°C, the rate of change of GPC with respect to temperature (ΔGPC, %) may be as small as, for example, 30% or less, less than 30%, 25% or less, 20% or less, 18% or less, 15% or less, 13% or less, or 12% or less.

[0079] According to another embodiment of the present invention, when forming a film using the film-forming composition at a process temperature of, for example, 300°C to 360°C, the rate of change of GPC with respect to temperature (ΔGPC, %) may be 30% or less, less than 30%, 25% or less, 20% or less, 18% or less, 15% or less, 13% or less, 12% or less, 11% or less, less than 11%, 10% or less, 8% or less, 7% or less, 6% or less, or 5% or less. Here, in Formula A, instead of GPC 250 GPC 300 (that is, GPC at 300°C) may be used for calculation.

[0080] According to another embodiment of the present invention, when forming a film using the film-forming composition at a process temperature of, for example, 330°C to 390°C, the rate of change of GPC with respect to temperature (ΔGPC, %) may be, for example, 30% or less, less than 30%, 25% or less, 20% or less, 18% or less, 15% or less, 13% or less, 12% or less, 11% or less, less than 11%, 8% or less, 7% or less, 6% or less, or 5% or less. Here, in Formula A, instead of GPC 250 GPC 330 (that is, GPC at 330°C) may be used for calculation.

[0081] According to another embodiment of the present invention, when forming a film using the film-forming composition at a process temperature of, for example, 360°C to 400°C, the rate of change of GPC with respect to temperature (ΔGPC, %) may be, for example, 30% or less, less than 30%, 25% or less, 20% or less, 18% or less, 15% or less, 13% or less, 12% or less, 11% or less, less than 11%, 8% or less, 7% or less, 6% or less, 5% or less, 4% or less, or 3% or less. Here, in formula A, GPC 250 may be used instead of GPC 360 (that is, GPC at 360°C) for calculation.

[0082] More specifically, the film-forming composition according to an embodiment of the present invention contains a Group 4 metal element-containing precursor compound represented by the following formula 2. When forming a zirconium (Zr)-containing film by ALD at a process temperature of 250°C to 380°C, the rate of change of GPC with respect to temperature (ΔGPC, %) represented by the above formula A may be, for example, 30% or less, less than 30%, 25% or less, 20% or less, 18% or less, 15% or less, 13% or less, 12% or less, 11% or less, less than 11%, 10% or less, 8% or less, 7% or less, 6% or less, 5% or less, or 4% or less.

[0083] [Chemical formula]

[0084] In formula 2, R1 is a methyl group, R2 is selected from the group consisting of linear or branched C3-C4 alkyl groups, and R3 to R8 are each independently selected from the group consisting of linear or branched C1-C4 alkyl groups.

[0085] Furthermore, when forming a film using the compound represented by Formula 2 at a process temperature of, for example, 250°C to 340°C, 250°C to 360°C, 250°C to 380°C, 300°C to 360°C, 330°C to 390°C, or 360°C to 400°C, the rate of change of GPC (ΔGPC, %) with respect to temperature is as small as 30% or less, respectively, as described above. That is, since GPC does not change significantly over a wide temperature range from low to high temperatures, a Group 4 metal element-containing film with a uniform thickness can also be formed on a surface having grooves with a large aspect ratio.

[0086] The Group 4 metal element-containing precursor compound may be a compound represented by any one of the following Formulas 2-1 to 2-3.

[0087]

Chemical formula

[0088] Furthermore, the film-forming composition contains a Group 4 metal element-containing precursor compound represented by the following Formula 3. When forming a hafnium (Zr)-containing film by ALD at a process temperature of 250°C to 400°C, the rate of change of GPC (ΔGPC, %) with respect to the temperature represented by the above Formula A may be as small as, for example, 30% or less, less than 30%, 25% or less, 20% or less, 18% or less, 15% or less, 13% or less, 12% or less, 11% or less, less than 11%, 10% or less, 8% or less, 7% or less, 6% or less, 5% or less, 4% or less, 3% or less, 1% or less, less than 1%, 0% or less, or less than 0%.

[0089]

Chemical formula

[0090] In Formula 3, R1 is a methyl group, R2 is selected from the group consisting of linear or branched C3-C4 alkyl groups, and R3 to R8 are each independently selected from the group consisting of linear or branched C1-C4 alkyl groups.

[0091] Furthermore, when forming a film using the compound represented by Formula 3 at a process temperature of, for example, 250°C to 340°C, 250°C to 360°C, 250°C to 380°C, 250°C to 400°C, 250°C to 420°C, 250°C to 430°C, 300°C to 360°C, 330°C to 390°C, or 360°C to 400°C, the rate of change of GPC with respect to temperature (ΔGPC, %) is as described, each being as small as 30% or less. That is, since GPC does not change significantly over a wide temperature range from low temperature to high temperature, a Group 4 metal element-containing film with a uniform thickness can also be formed on a surface having grooves with a large aspect ratio.

[0092] The Group 4 metal element-containing precursor compound may be a compound represented by any one of the following Formulas 3-1 to 3-3.

[0093] [Chemical formula]

[0094] The rate of change of GPC with respect to temperature (ΔGPC, %) can be measured in units of 1°C to 50°C during film formation. Specifically, the rate of change of GPC with respect to temperature (ΔGPC, %) can be measured in units of, for example, 5°C, 10°C, 15°C, 20°C, 25°C, or 30°C.

[0095] On the other hand, when forming a Group 4 metal element-containing film by ALD using ozone (O3) as a reaction gas with a Group 4 metal element-containing precursor compound, it is possible to achieve a GPC of 0.5 to 1.0 Å / cycle, 0.6 to 1.0 Å / cycle, 0.7 to 1.0 Å / cycle, 0.8 to 1.0 Å / cycle, 0.6 to 0.9 Å / cycle, 0.7 to 0.9 Å / cycle, 0.8 to 0.9 Å / cycle, 0.6 to 0.8 Å / cycle, or 0.7 to 0.8 Å / cycle at 150°C to 400°C.

[0096] For example, when the Group 4 metal element-containing precursor compound is a Group 4 metal element-containing precursor compound represented by Formula 2 and a zirconium (Zr)-containing film is formed by ALD using ozone (O3) as a reaction gas, the GPC may be 0.5 to 0.9 Å / cycle, 0.6 to 0.9 Å / cycle, 0.7 to 0.9 Å / cycle, or 0.8 to 0.9 Å / cycle at 150°C to 400°C, for example, 200°C to 400°C or 250°C to 400°C.

[0097] As another example, when the Group 4 metal element-containing precursor compound is a Group 4 metal element-containing precursor compound represented by Formula 3 and a hafnium (Hf)-containing film is formed by ALD using ozone (O3) as a reaction gas, the GPC may be 0.5 to 0.9 Å / cycle, 0.6 to 0.9 Å / cycle, 0.7 to 0.9 Å / cycle, 0.6 to 0.8 Å / cycle, or 0.7 to 0.8 Å / cycle at 150°C to 410°C, for example, 150°C to 400°C or 250°C to 400°C.

[0098] The Group 4 metal element-containing precursor compound has a specific structure of Formula 1, for example, Formula 2 or Formula 3, and by using a film-forming composition containing the precursor compound, a Group 4 metal element-containing film can be uniformly formed by ALD in a wide temperature range.

[0099] The Group 4 metal element-containing precursor compound represented by Formula 1, for example, Formula 2 or Formula 3, can be synthesized by using an alkyl-substituted cyclopentadiene instead of cyclopentadiene (C5H6) in the generally known synthesis method of the CpZr(NMe2)3 compound or the CpHf(NMe2)3 compound. MODE FOR INVENTION

[0100] Hereinafter, the present invention will be described in detail with reference to examples. The following examples illustrate the present invention, and the scope of the present invention is not limited thereto.

[0101] Preparation Example <Preparation Example 1> Preparation of 1-Methyl-3-propylcyclopenta-1,3-diene

Chemical formula

[0102] A 1-L Schlenk flask dried by flame was filled with about 27 g (about 0.281 mol) of 3-methyl-2-cyclopenten-1-one (MCPO) and about 100 mL of tetrahydrofuran (THF, C4H8O) at room temperature. About 40.4 g (about 0.393 mol) of n-propylmagnesium chloride ( n PrMgCl) was slowly added dropwise to the flask, and then the reaction solution was stirred at room temperature for about 4 hours.

[0103] About 33.7 g (about 0.562 mol) of acetic acid (CH3COOH) mixed with about 200 mL of distilled water (DI water) was slowly added dropwise to the flask, and then the reaction solution was stirred at room temperature for 1 day. The aqueous layer was removed using a separatory funnel. Then, about 14.9 g (about 0.140 mol) of sodium carbonate (Na2CO3) mixed with about 150 mL of distilled water (DI water) was slowly added dropwise, and the reaction solution was stirred at room temperature for about 2 hours. The aqueous layer was removed using a separatory funnel. Then, water was removed using magnesium sulfate (MgSO4). The solvent was removed under reduced pressure, and the resulting product was distilled under reduced pressure to obtain about 17 g (yield 49.5%) of 1-methyl-3-n-propylcyclopenta-1,3-diene represented by Formula 4-1 as a colorless transparent liquid compound, and a composition for film formation was prepared using this.

[0104] <Preparation Example 2> Preparation of 3-butyl-1-methylcyclopenta-1,3-diene

Chemical formula

[0105] Instead of n-propylmagnesium chloride ( n PrMgCl), n-butylmagnesium chloride ( nUsing the same method as in Preparation Example 1 except for using BuMgCl, about 18 g (yield 47%) of 3-butyl-1-methylcyclopenta-1,3-diene represented by Formula 4-2 was obtained as a colorless transparent liquid compound, and a film-forming composition was synthesized using this compound.

[0106] <Preparation Example 3> Preparation of Methylpropylcyclopentadiene Mixed Composition

Chemical Formula

[0107] A 1000 mL Schlenk flask dried by flame was filled with about 50.0 g (0.624 mol) of methylcyclopentadiene and about 400 mL of tetrahydrofuran (THF, C4H8O) at room temperature and cooled to -20°C. About 173.79 g (0.624 mol) of n-butyllithium ( n BuLi) was slowly added dropwise to the flask while maintaining the temperature at -20°C, and then the reaction solution was stirred at room temperature for about 4 hours.

[0108] After completion of the reaction, 67.07 g (0.562 mol) of 1-bromopropane (C3H7Br) was slowly added dropwise while maintaining the temperature at -20°C, and then the reaction solution was slowly warmed to room temperature and stirred for 12 hours.

[0109] After completion of the reaction, the salt formed during the reaction was removed by a filtration process, the organic layer was extracted with diethyl ether ((C2H5)2O), the moisture was removed using magnesium sulfate (MgSO4), the solvent and volatile by-products were removed by distillation under reduced pressure, and 28.12 g (37.2%) of a colorless transparent liquid mixed composition represented by Formula 4-1, Formula 4-3, and Formula 4-4 was obtained. A film-forming composition of Comparative Example 5 was synthesized using this.

[0110] <Preparation Example 4> Preparation of Diethylcyclopentadiene Mixed Composition

Chemical Formula

[0111] A flame-dried 1-liter Schlenk flask was filled with about 41.88 g (about 1.074 moles) of sodium amide (NaNH2) and about 500 mL of tetrahydrofuran (THF, C4H8O), and then stirred. About 100 g (about 1.074 moles) of ethylcyclopentadiene (C7H 10 ) was slowly added at about -20 °C, and then the temperature was gradually raised to room temperature with stirring, and then it was stirred for 17 hours. After completion of the reaction, about 116.98 g (about 1.074 moles) of bromoethane (C2H5Br) was slowly added at about -20 °C, and then the temperature was gradually raised to room temperature with stirring, and then it was stirred for 17 hours. After completion of the reaction, the salts formed during the reaction were removed by a filtration process, and the solvent and volatile by-products were removed by distillation under reduced pressure to obtain 62 g (yield 47.7%) of a colorless transparent liquid mixture composition represented by Formula 4-5, Formula 4-6, and Formula 4-7. Using this, a film-forming composition of Comparative Example 4 was synthesized.

[0112] Example <Example 1> [(Me, n Pr)Cp]Zr(NMe2)3 and Preparation of a Film-Forming Composition Containing the Same

Chemical Formula

[0113] A flame-dried 1-liter Schlenk flask was filled with about 80 g (about 0.300 moles) of tetrakis(dimethylamido)zirconium(VI) and about 500 mL of n-hexane (C6H 14 ) at room temperature. About 39 g (about 0.315 moles) of 1-methyl-3-propylcyclopenta-1,3-diene obtained in Preparation Example 1 was slowly added dropwise to the flask, and then the reaction solution was stirred at room temperature for about 3 hours.

[0114] After completion of the reaction, the solvent was removed under reduced pressure, and the resulting product was distilled under reduced pressure to obtain about 61 g (yield 60%) of a pale yellow liquid compound represented by Formula 2-1, and using this, a film-forming composition was prepared.

[0115] Boiling point (bp): 100 °C (0.3 Torr) 1 1H-NMR (400 MHz, C6D6, 25 °C): δ 5.797, 5.763 (m, 3H, [(CH3CH2CH2)(CH3)(C5H * 3)]Zr[N(CH3)2]3, δ 3.033 (s, 18H, [(CH3CH2CH2)(CH3)(C5H3)]Zr[N(CH * 3)2]3, δ 2.448 (t, 2H, [(CH3CH2CH * 2)(CH3)(C5H3)]Zr[N(CH3)2]3, δ 2.094 (s, 3H, [(CH3CH2CH2)(CH * 3)(C5H3)]Zr[N(CH3)2]3, δ 1.577 (m, 2H, [(CH3CH * 2CH2)(CH3)(C5H3)]Zr[N(CH3)2]3, δ 0.923 (t, 3H, [(CH * 3CH2CH2)(CH3)(C5H3)]Zr[N(CH3)2]3

[0116] <Example 2> Preparation of [(Me,nBu)Cp]Zr(NMe2)3 and a film-forming composition containing the same

Chemical formula

[0117] A pale yellow liquid compound represented by Formula 2-2, about 65 g (yield 60%), was obtained in the same manner as in Example 1, except that 3-butyl-1-methylcyclopenta-1,3-diene obtained in Preparation Example 2 was used instead of 1-methyl-3-propylcyclopenta-1,3-diene, and a film-forming composition was synthesized using this compound.

[0118] Boiling point (bp): 110 °C (0.3 Torr) 1 1H-NMR (400 MHz, C6D6, 25 °C): δ 5.818, 5.777 (m, 3H, [(CH3CH2CH2CH2)(CH3)(C5H * 3)]Zr[N(CH3)2]3, δ 2.973 (s, 18H, [(CH3CH2CH2CH2)(CH3)(C5H3)]Zr[N(CH * 3)2]3, δ 2.493 (t, 2H, [(CH3CH2CH2CH * 2)(CH3)(C5H3)]Zr[N(CH3)2]3, δ 2.102 (s, 3H, [(CH3CH2CH2CH2)(CH * 3)(C5H3)]Zr[N(CH3)2]3, δ 1.547 (m, 2H, [(CH3CH2CH * 2CH2)(CH3)(C5H3)]Zr[N(CH3)2]3, δ 1.338 (m, 2H, [(CH3CH * 2CH2CH2)(CH3)(C5H3)]Zr[N(CH3)2]3, δ 0.904 (t, 3H, [(CH * 3CH2CH2CH2)(CH3)(C5H3)]Zr[N(CH3)2]3

[0119] <Example 3> Preparation of [(Me,nPr)Cp]Hf(NMe2)3 and a film-forming composition containing the same

Chemical formula

[0120] A 1-liter Schlenk flask dried by flame was filled with about 65 g (about 0.184 mol) of tetrakis(dimethylamide)hafnium(VI) and about 400 mL of n-hexane (C6H 14 ) at room temperature. About 27 g (about 0.220 mol) of 1-methyl-3-propylcyclopenta-1,3-diene obtained in Preparation Example 1 was slowly added dropwise to the flask, and then the reaction solution was stirred at room temperature for about 3 hours.

[0121] After the reaction was completed, the solvent was removed under reduced pressure, and the resulting product was distilled under reduced pressure to obtain about 42 g (yield 53%) of a pale yellow liquid compound represented by Formula 3-1. A film-forming composition was prepared using this compound.

[0122] Boiling point (bp): 100 °C (0.3 Torr) 1 H-NMR (400 MHz, C6D6, 25 °C): δ 5.750, 5.724 (m, 3H, [(CH3CH2CH2)(CH3)(C5H * 3)]Hf[N(CH3)2]3, δ 2.987 (s, 18H, [(CH3CH2CH2)(CH3)(C5H3)]Hf[N(CH * 3)2]3, δ 2.466 (t, 2H, [(CH3CH2CH * 2)(CH3)(C5H3))Hf[N(CH3)2]3, δ 2.119 (s, 3H, [(CH3CH2CH2)(CH * 3)(C5H3))Hf[N(CH3)2]3, δ 1.541 (m, 2H, [(CH3CH * 2CH2)(CH3)(C5H3))Hf[N(CH3)2]3, δ 0.909 (t, 3H, [(CH * 3CH2CH2)(CH3)(C5H3))Hf[N(CH3)2]3

[0123] <Example 4> Preparation of [(Me,nBu)Cp]Hf(NMe2)3 and a Film-Forming Composition Containing the Same

Chemical Formula

[0124] A pale yellow liquid compound represented by Formula 3-2 was obtained in an amount of about 65 g (yield 60%) using the same method as in Example 3, except that 3-butyl-1-methylcyclopenta-1,3-diene obtained in Preparation Example 2 was used instead of 1-methyl-3-propylcyclopenta-1,3-diene. A film-forming composition was synthesized using this compound.

[0125] Boiling point (bp): 110 °C (0.3 Torr) 1 1H-NMR (400 MHz, C6D6, 25 °C): δ 5.767, 5.759 (m, 3H, [(CH3CH2CH2CH2)(CH3)(C5H * 3)]-Hf[N(CH3)2]3, δ 3.011 (s, 18H, [(CH3CH2CH2CH2)(CH3)(C5H3)]Hf[N(CH * 3)2]3, δ 2.524 (t, 2H, [(CH3CH2CH2CH * 2)(CH3)(C5H3)]Hf[N(CH3)2]3, δ 2.132 (s, 3H, [(CH3CH2CH2CH2)(CH * 3)(C5H3)]Hf[N(CH3)2]3, δ 1.537 (m, 2H, [(CH3CH2CH * 2CH2)(CH3)(C5H3)]Hf[N(CH3)2]3, δ 1.330 (m, 2H, [(CH3CH * 2CH2CH2)(CH3)(C5H3)]Hf[N(CH3)2]3, δ 0.901 (t, 3H, [(CH * 3CH2CH2CH2)(CH3)(C5H3)]Hf[N(CH3)2]3

[0126] <Comparative Example 1> The product of UP Chemical's cyclopentadienyl-tris(dimethylamide)zirconium (CpZr(NMe2)3 or CpZr) was used.

[0127] <Comparative Example 2> The product of UP Chemical's cyclopentadienyl-tris(dimethylamide)hafnium (CpHf(NMe2)3 or CpHf) was used.

[0128] <Comparative Example 3> UP Chemical's n propylcyclopentadienyl-tris(dimethylamide)zirconium (n PrCp)Zr(NMe2)3 or n a product of PrCpZr) was used.

[0129] <Comparative Example 4> Preparation of [(Et)2Cp]Zr(NMe2)3 Mixed Composition

Chemical formula

[0130] Except for using the diethylcyclopentadiene mixed composition represented by Formulas 4-5 to 4-7 obtained in Preparation Example 4 instead of 1-methyl-3-propylcyclopenta-1,3-diene, the same method as in Example 1 was used to obtain a pale yellow liquid mixed composition represented by Formulas 2-4 and 2-5, about 49 g (yield 71.1%). A film-forming composition was synthesized using this.

[0131] <Comparative Example 5> Preparation of [(nPr,Me)Cp]Hf(NMe2)3 Mixed Composition

Chemical formula

[0132] A 1-liter Schlenk flask dried by flame was filled with about 54 g (about 0.152 mol) of tetrakis(dimethylamide)hafnium(VI) and about 500 mL of n-hexane (C6H 14 ) at room temperature. About 27 g (about 0.220 mol) of the methylpropylcyclopentadiene mixture represented by Formulas 4-1, 4-3, and 4-4 obtained in Preparation Example 3 was slowly added dropwise to the flask, and then the reaction solution was stirred at room temperature for about 3 hours.

[0133] After completion of the reaction, the solvent was removed under reduced pressure, and the resulting product was distilled under reduced pressure to obtain a pale yellow liquid mixed composition represented by Formulas 3-1 and 3-4 having a composition of about 1:1.87, about 42.2 g (yield 64%). The ratio of the two isomers having the same molecular weight is 1In the 1H-NMR (400 MHz, C6D6, 25 °C) spectrum, it was determined as the relative ratio of the integral values of the 1H-NMR peaks of the methyl (CH3) hydrogen atoms bonded to the cyclopentadiene ring of the ligand at 2.119 ppm (Formula 3-1) and 2.043 ppm (Formula 3-4). 1 - Determined as the relative ratio of the integral values of the 1H-NMR peaks.

[0134] Boiling point (bp): 100 °C (0.3 Torr) 1 1H-NMR (400 MHz, C6D6, 25 °C): Compound represented by Formula 3-1: [(1- n Pr,3-Me)Cp]Hf(NMe2)3 δ 5.750, 5.724 (m, 3H, [(CH3CH2CH2)(CH3)(C5H * 3)]Hf[N(CH3)2]3, δ 2.987 (s, 18H, [(CH3CH2CH2)(CH3)(C5H3)]Hf[N(CH * 3)2]3, δ 2.466 (t, 2H, [(CH3CH2CH * 2)(CH3)(C5H3))Hf[N(CH3)2]3, δ 2.119 (s, 3H, [(CH3CH2CH2)(CH * 3)(C5H3))Hf[N(CH3)2]3, δ 1.541 (m, 2H, [(CH3CH * 2CH2)(CH3)(C5H3))Hf[N(CH3)2]3, δ 0.909 (t, 3H, [(CH * 3CH2CH2)(CH3)(C5H3))Hf[N(CH3)2]3 Compound represented by Formula 3-4: [(1- n Pr,2-Me)Cp]Hf(NMe2)3 δ 5.913, 5.842 (m, 3H [(CH3CH2CH2)(CH3)(C5H * 3)]Hf[N(CH3)2]3, δ 2.995 (s, 18H, [(CH3CH2CH2)(CH3)(C5H3)]Hf[N(CH * 3)2]3, δ 2.408 (t, 2H, [(CH3CH2CH * 2)(CH3)(C5H3))Hf[N(CH3)2]3, δ 2.043 (s, 3H, [(CH3CH2CH2)(CH * 3)(C5H3))Hf[N(CH3)2]3, δ 1.498 (m, 2H, [(CH3CH * 2CH2)(CH3)(C5H3))Hf[N(CH3)2]3, δ 0.886 (t, 3H, [(CH * 3CH2CH2)(CH3)(C5H3))Hf[N(CH3)2]3

[0135] Test Example <Test Example 1> Structural Analysis of Precursor Compounds 1 1H-NMR (400 MHz, C6D6, 25 °C) analysis was performed to analyze the structures of the Group 4 metal element-containing precursor compounds prepared in the examples and comparative examples. The results are shown in the above examples and comparative examples.

[0136] Furthermore, as can be seen from Fig. 1, the hafnium (Hf)-containing precursor compound of Comparative Example 5 had a composition of two structures (mixed structure) due to structural isomers. 1 In the 1H-NMR spectrum, at 2.119 ppm (Formula 3-1) and 2.043 ppm (Formula 3-4) where the hydrogen of the methyl (CH3) bonded to the cyclopentadiene ring of the ligand appears 1 1H-NMR peaks were observed (the ratio of Formula 3-1 to Formula 3-4 (relative ratio of peak integral values) was approximately 1:1.87). On the other hand, the hafnium (Hf)-containing precursor compound prepared in Example 3 of the present invention 1 was confirmed to have a single composition in 1H-NMR analysis.

[0137] From the results of the structural analysis, it was confirmed that the hafnium (Hf)-containing precursor compound of Example 3 is a precursor of sufficiently high purity to be applied to the ALD process. Therefore, the Group 4 metal element-containing precursor compound prepared by the method of the examples can be used for the purpose of forming various films.

[0138] <Test Example 2> Evaluation of Zirconium (Zr)-containing Oxide Film Formed by Atomic Layer Deposition (ALD) and GPC with Respect to Temperature Using the film-forming composition containing the zirconium (Zr)-containing precursor compound prepared by the method of Example 1 and ozone (O3) as the reaction gas, a zirconium (Zr)-containing oxide film was formed on a silicon substrate heated to a temperature (process temperature) of about 250°C to 400°C by ALD.

[0139] Specifically, first, a silicon substrate was prepared in an ALD reaction chamber.

[0140] Thereafter, the film-forming composition prepared by the method of Example 1 was filled into a stainless steel canister and heated to about 120°C. An argon (Ar) carrier gas was flowed through the stainless steel canister at a flow rate of about 200 to 500 sccm, and the gaseous film-forming composition was supplied to the reaction chamber. The temperature of the gas supply pipe connected from the stainless steel canister to the reaction chamber was about 120°C to 150°C. It was hotter closer to the reaction chamber. Oxygen gas (O2) was supplied to an ozone (O3) generator at a flow rate of 500 to 1000 sccm to generate ozone (O3) at a concentration of about 180 to 220 g / m 3 and this was supplied to the reaction chamber and used as the reaction gas. In order to remove the zirconium (Zr)-containing precursor, ozone (O3), and reaction by-products remaining in the reaction chamber, argon (Ar) gas was supplied to the reaction chamber at a flow rate of about 500 to 2000 sccm. The processing pressure of the reaction chamber was maintained at 0.9 to 1.2 Torr.

[0141] The ALD gas supply cycle was repeated 100 times to form a zirconium (Zr)-containing oxide film. Here, each ALD gas supply cycle includes a step of supplying a gaseous film-forming composition for about 5 to 30 seconds, a step of supplying argon (Ar) gas for about 5 to 30 seconds to remove the film-forming composition (gas) remaining in the reactor, a step of supplying ozone (O3) as a reaction gas for about 5 to 30 seconds, and a step of supplying argon (Ar) gas for about 5 to 30 seconds to remove the ozone (O3) remaining in the reactor.

[0142] Using the compositions containing the zirconium (Zr)-containing precursor compounds of Comparative Example 1, Comparative Example 3, and Comparative Example 4, stainless steel canisters were heated to 100 °C, 110 °C, and 120 °C, respectively, to vaporize the respective compositions containing the zirconium (Zr)-containing precursor compounds of Comparative Example 1, Comparative Example 3, and Comparative Example 4. Then, zirconium (Zr) oxide films were formed under the same conditions as in the above film formation method of Test Example 2.

[0143] The thicknesses of the respective zirconium (Zr) oxide films formed using the film-forming compositions prepared by the methods of Example 1, Comparative Example 1, Comparative Example 3, and Comparative Example 4 were measured using a polarization analyzer (M-2000, J.A. Woollam).

[0144] Thereafter, the measured thickness was divided by the number of gas supply cycles (100 times) to calculate the GPC. Specifically, the GPC regarding the temperature (process temperature) in the range of 250 °C to 400 °C was calculated. The results are shown in Figure 2 and Table 1.

[0145] Furthermore, the rate of change (ΔGPC, %) of the GPC with respect to the process temperature according to the following formula A was calculated. The results are shown in Table 1.

[0146]

Equation

[0147] In Equation A, GPC 250 is the GPC at 250 °C, and GPC tempis GPC at the process temperature.

[0148] <Test Example 3> Evaluation of GPC of hafnium (Hf)-containing oxide film formed by atomic layer deposition (ALD) and temperature Using a film-forming composition containing a hafnium (Hf)-containing precursor compound prepared by the method of Example 3 and ozone (O3) as a reaction gas, a hafnium (Hf)-containing oxide film was formed on a silicon substrate heated to a process temperature of about 250°C to 400°C by ALD.

[0149] Specifically, first, a silicon substrate was prepared in an ALD reaction chamber.

[0150] Thereafter, the film-forming composition prepared by the method of Example 3 was filled in a stainless steel canister and heated to about 120°C. An argon (Ar) carrier gas was flowed through the stainless steel canister at a flow rate of about 200 to 500 sccm, and the gaseous film-forming composition was supplied to the reaction chamber. The temperature of the gas supply pipe connected from the stainless steel canister to the reaction chamber was about 120°C to 150°C. It was hotter closer to the reaction chamber. Oxygen gas (O2) was supplied to an ozone (O3) generator at a flow rate of 500 to 1000 sccm to generate ozone (O3) at a concentration of about 180 to 220 g / m 3 and this was supplied to the reaction chamber and used as a reaction gas. In order to remove the hafnium (Hf)-containing precursor, ozone (O3), and reaction by-products remaining in the reaction chamber, argon (Ar) gas was supplied to the reaction chamber at a flow rate of about 500 to 2000 sccm. The processing pressure of the reaction chamber was maintained at 0.9 to 1.2 Torr.

[0151] The ALD gas supply cycle was repeated 100 times to form a hafnium (Hf)-containing oxide film. Here, each ALD gas supply cycle includes a step of supplying a film-forming composition in a gaseous state for about 5 to 30 seconds, a step of supplying argon (Ar) gas for about 5 to 30 seconds to remove the film-forming composition (gas) remaining in the reactor, a step of supplying ozone (O3) as a reaction gas for about 5 to 30 seconds, and a step of supplying argon (Ar) gas for about 5 to 30 seconds to remove the ozone (O3) remaining in the reactor.

[0152] Using the film-forming composition containing the hafnium (Hf)-containing precursor compound of Comparative Example 2, a stainless steel canister was heated to 100 °C to vaporize the film-forming composition containing the hafnium (Hf)-containing precursor compound of Comparative Example 2. Then, a hafnium (Hf) oxide film was formed under the same conditions as in the film formation method of Test Example 3.

[0153] The thicknesses of the respective hafnium (Hf) oxide films formed using the film-forming compositions prepared by the methods of Example 3 and Comparative Example 2 were measured using a polarization analyzer (M-2000, J.A. Woollam).

[0154] Thereafter, the GPC was calculated by dividing the measured thickness by the number of gas supply cycles (100 times). Specifically, the GPC regarding the temperature (process temperature) in the range of 250 °C to 450 °C was calculated. The results are shown in Figure 3 and Table 2.

[0155] Furthermore, the rate of change (ΔGPC, %) of the GPC with respect to temperature according to the above formula A was calculated. The results are shown in Table 2.

[0156]

Table 1

[0157] As can be seen from FIG. 2 and Table 1, when using the film-forming composition containing the zirconium (Zr)-containing precursor compound of the present invention, self-limiting film growth of ALD could be achieved in a wide temperature range, particularly at high temperatures. Furthermore, when using the film-forming composition of Example 1, GPC did not change.

[0158] Specifically, when using the film-forming compositions of Comparative Example 1 and Comparative Example 4 respectively, the precursor compounds had low thermal stability. Therefore, as the temperature increased, GPC changed rapidly, resulting in a GPC change rate (ΔGPC) exceeding 100% at 330 °C or 360 °C respectively.

[0159] This is considered to be due to the film growing by gas-phase reaction other than surface reaction due to the thermal decomposition of the precursor compounds used in Comparative Example 1 and Comparative Example 4. That is, when the film grows by gas-phase reaction, the film grows rapidly above the groove, while the film grows slowly in the lower part (bottom) of the narrow and deep groove. In such a case, the merit of ALD that a film with a uniform thickness can be formed on the surface with deep grooves by surface reaction cannot be obtained.

[0160] On the other hand, when using the film-forming composition of Example 1 of the present invention, the zirconium (Zr)-containing precursor compound contained in the film-forming composition had excellent thermal stability without thermal decomposition. Therefore, even when high temperature was used for ALD, GPC did not change, and the change rate of GPC (ΔGPC) was maintained at 10% or less up to about 370 °C.

[0161] Furthermore, when using the film-forming composition of Comparative Example 3, the change rate of GPC (ΔGPC) at 380 °C was about 22%, showing a significant difference from Example 1 where the change rate of GPC (ΔGPC) was about 12% at the same temperature.

[0162] [Table 2]

[0163] As can be seen from FIG. 3 and Table 2, when the film-forming composition containing the hafnium (Hf)-containing precursor compound of the present invention was used, self-limiting film growth of ALD could be achieved in a wide temperature range, particularly at high temperatures. Furthermore, when the film-forming composition of Example 3 was used, GPC did not change.

[0164] Specifically, in Comparative Example 2, the precursor compound had low thermal stability. Therefore, as the temperature increased, GPC changed rapidly, resulting in a change rate of GPC (ΔGPC) exceeding 100% at 400°C.

[0165] This is considered to be due to the film growing by gas-phase reaction other than surface reaction due to the thermal decomposition of the precursor compound used in Comparative Example 2. That is, when the film grows by gas-phase reaction, the film grows rapidly above the groove, while it grows slowly in the lower part (bottom) of the narrow and deep groove. In such a case, the merit of ALD that a film of uniform thickness can be formed on a surface with deep grooves by surface reaction cannot be obtained.

[0166] On the other hand, in Example 3 of the present invention, the hafnium (Hf)-containing precursor compound contained in the film-forming composition had excellent thermal stability without thermal decomposition. Therefore, even when a high temperature was used in ALD, GPC did not change, and the change rate of GPC (ΔGPC) was maintained at 8% or less up to about 440°C.

[0167] <Test Example 4> Evaluation of Step Coverage of Zirconium (Zr)-Containing Oxide Film The step coverages of the zirconium (Zr)-containing oxide films formed using the film-forming compositions of Example 1, Comparative Example 1, Comparative Example 3, and Comparative Example 4 were evaluated, respectively.

[0168] Specifically, using the film-forming compositions of Example 1, Comparative Example 1, Comparative Example 3, and Comparative Example 4, respectively, a zirconium (Zr)-containing oxide film having a thickness of about 12 to 15 nm was formed on a substrate having grooves with an aspect ratio of 20:1 in a silicon oxide (SiO2) film by ALD at process temperatures of about 300°C, 340°C, and 360°C.

[0169] The thickness and step coverage rate (%) of the zirconium (Zr)-containing oxide film were measured in the transmission electron microscope (TEM) images of the upper, middle, and lower parts of the grooves shown in FIGS. 4 and 5.

[0170] [Table 3]

[0171] [Table 4]

[0172] As can be seen from FIGS. 4 and 5 and Tables 3 and 4, when a zirconium (Zr)-containing oxide film was formed on a substrate having grooves with an aspect ratio of 20:1 at 300 °C, 340 °C, and 360 °C using the film-forming composition of Example 1 of the present invention, the step coverage rate (%) was excellent compared to Comparative Example 1, Comparative Example 3, and Comparative Example 4.

[0173] Furthermore, when the film-forming composition of Example 1 was used, it was confirmed that a zirconium (Zr)-containing oxide film having an extremely uniform thickness with a step coverage rate of about 99.3% was formed even at a high temperature of about 360 °C.

[0174] From the above results, by using the film-forming composition containing the zirconium (Zr)-containing precursor compound of the present invention, self-limiting film growth of ALD can be achieved in a wide temperature range, particularly at a high temperature of about 360 °C, and it was confirmed that zirconium (Zr)-containing films for various applications can be formed at a wide range of process temperatures.

[0175] In particular, according to the method for forming a zirconium (Zr)-containing film of the present invention, since the GPC does not change in a wide temperature range, it is possible to form a zirconium (Zr)-containing film with a uniform thickness even on a surface having grooves with a large aspect ratio. Therefore, it can be advantageously used for manufacturing various semiconductor devices such as DRAM and 3D NAND flash memories.

[0176] <Test Example 5> Evaluation of Step Coverage of Hafnium (Hf)-Containing Oxide Film The step coverages of hafnium (Hf)-containing oxide films formed using the film-forming compositions of Example 3 and Comparative Example 2 were evaluated, respectively.

[0177] Specifically, using the film-forming compositions of Example 3 and Comparative Example 2 respectively, a hafnium (Hf)-containing oxide film having a thickness of about 6 - 7 nm was formed by ALD at process temperatures of about 350 °C and about 400 °C on a substrate on which a titanium nitride (TiN) film was formed in a groove with an aspect ratio of 11:1.

[0178] The thickness and step coverage (%) of the hafnium (Hf)-containing oxide film were measured in the transmission electron microscope (TEM) images of the upper, middle, and lower parts of the groove shown in Fig. 6.

[0179] [Table 5]

[0180] As can be seen from Fig. 6 and Table 5, when a hafnium (Hf)-containing oxide film was formed at 350 °C and 400 °C on a substrate having a step with an aspect ratio of 11:1 using the film-forming composition of Example 3 of the present invention, the step coverage (%) was good.

[0181] Specifically, when the film-forming composition of Example 3 was used, it was confirmed that a hafnium (Hf)-containing oxide film having an extremely uniform thickness with a step coverage of about 98.7% was formed even at a high temperature of about 400 °C.

[0182] From the above results, by using the film-forming composition containing the hafnium (Hf)-containing precursor compound of the present invention, self-limiting film growth of ALD can be achieved in a wide temperature range, particularly at a high temperature of about 400 °C, and it was confirmed that hafnium (Hf)-containing films for various applications can be formed at a wide range of process temperatures.

[0183] In particular, according to the method for forming a hafnium (Hf)-containing film of the present invention, since the GPC does not change in a wide temperature range, it is possible to form a hafnium (Hf)-containing film with a uniform thickness even on a surface having grooves with a large aspect ratio. Therefore, it can be advantageously used for manufacturing various semiconductor devices such as DRAM and 3D NAND flash memories.

Claims

1. A method for forming a Group 4 metal element-containing film, comprising reacting a film-forming composition containing a Group 4 metal element-containing precursor compound represented by the following formula 1 with a reaction gas to form a Group 4 metal element-containing film on a substrate. 【Chemical 1】 [In Formula 1, M is Zr or Hf, and R １ is a methyl group, and R ２ is selected from the group consisting of linear or branched C ３ to C ４ alkyl groups, and R ３ to R ８ are each independently selected from the group consisting of linear or branched C １ to C ４ alkyl groups.]

2. The method for forming a Group 4 metal element-containing film is a step of preparing at least a part of the substrate in a reaction chamber, a step of supplying the film-forming composition in a gaseous state to the reaction chamber, and a step of supplying the reaction gas to the reaction chamber, wherein a Group 4 metal element-containing film is formed on at least a part of the surface of the substrate by chemical vapor deposition (CVD) or atomic layer deposition (ALD). The method for forming a Group 4 metal element-containing film according to claim 1.

3. The method for forming a Group 4 metal element-containing film according to claim 1, wherein film formation is carried out in a temperature range of 150°C to 500°C.

4. The method for forming a Group 4 metal element-containing film according to claim 1, wherein the Group 4 metal element-containing precursor compound has a single-composition structure.

5. The method for forming a Group 4 metal element-containing film according to claim 1, wherein the Group 4 metal element-containing precursor compound is a compound represented by the following formula 2. [Chemical Formula 2] [In Formula 2, R １ is a methyl group, and R ２ is selected from the group consisting of linear or branched C ３ to C ４ alkyl groups, and R ３ to R ８ are each independently selected from the group consisting of linear or branched C １ to C ４ alkyl groups.]

6. The method for forming a Group 4 metal element-containing film according to claim 5, wherein the Group 4 metal element-containing precursor compound is a compound represented by one of the following formulas 2-1 to 2-3. [Chemical Formula 3]

7. When a zirconium (Zr)-containing film is formed by atomic layer deposition (ALD) at a process temperature of 250°C to 380°C using the compound represented by formula 2, the change rate (ΔGPC, %) of the film formation rate (GPC) with respect to the temperature represented by the following formula A is 30% or less. The method for forming a Group 4 metal element-containing film according to claim 5. 【Number 1】 [In Formula A, GPC ２５０ is GPC at 250 °C, and GPC ｔｅｍｐ is GPC at the process temperature.]

8. The method for forming a Group 4 metal element-containing film according to claim 7, wherein when a zirconium (Zr)-containing film is formed by atomic layer deposition (ALD) at a process temperature of 250°C to 400°C using the compound represented by formula 2, the change rate (ΔGPC, %) of GPC is 30% or less.

9. The method for forming a Group 4 metal element-containing film according to claim 7, wherein when a zirconium (Zr)-containing film is formed by atomic layer deposition (ALD) at a process temperature of 250°C to 360°C using the compound represented by formula 2, the change rate (ΔGPC, %) of GPC is 30% or less.

10. The method for forming a Group 4 metal element-containing film according to claim 1, wherein the Group 4 metal element-containing precursor compound is a compound represented by the following formula 3. [Chemical Formula 4] [In Formula 3, R １ is a methyl group, and R ２ is selected from the group consisting of linear or branched C ３ -C ４ alkyl groups, and R ３ to R ８ are each independently selected from the group consisting of linear or branched C １ -C ４ alkyl groups. ]

11. The method for forming a Group 4 metal element-containing film according to claim 10, wherein the Group 4 metal element-containing precursor compound is a compound represented by one of the following formulas 3-1 to 3-3. [Chemical Formula 5]

12. When a hafnium (Hf)-containing film is formed by atomic layer deposition (ALD) at a process temperature of 250°C to 400°C using the compound represented by formula 3, the rate of change (ΔGPC, %) of the film formation rate (GPC) with respect to the temperature represented by the following formula A is 30% or less. The method for forming a Group 4 metal element-containing film according to claim 10. 【Number 2】 [In Formula A, GPC ２５０ is the GPC at 250°C, and GPC ｔｅｍｐ is the GPC at the process temperature.]

13. The method for forming a Group 4 metal element-containing film according to claim 1, wherein the Group 4 metal element-containing film is formed on a substrate having at least one groove with an aspect ratio of 1 or more and a width of 1 μm or less.

14. The method for forming a Group 4 metal element-containing film according to claim 1, wherein the Group 4 metal element-containing film is formed in a thickness range of 1 nm to 500 nm.

15. A film-forming composition containing a Group 4 metal element-containing precursor compound represented by the following formula 1. [Chemical Formula 6] [In Formula 1, M is Zr or Hf, and R １ is a methyl group, and R ２ is selected from the group consisting of linear or branched C ３ to C ４ alkyl groups, and R ３ to R ８ are each independently selected from the group consisting of linear or branched C １ to C ４ alkyl groups.]

16. The film-forming composition according to claim 15, wherein the Group 4 metal element-containing precursor compound is a compound represented by one of the following formulas 2-1 to 2-3. [Chemical Formula 7]

17. The film-forming composition according to claim 15, wherein the Group 4 metal element-containing precursor compound is a compound represented by one of the following formulas 3-1 to 3-3. 【Chemical 8】

18. The film-forming composition according to claim 15, wherein the Group 4 metal element-containing precursor compound has a single-composition structure.

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