Method for forming photosensitive organometallic oxides by chemical vapor polymerization

Abstract

Method embodiments are provided for forming an EUV-active photoresist film for use in an EUV photolithography process. The methods disclosed herein may generally include forming an extreme ultraviolet (EUV)-active photoresist film on a surface of a semiconductor substrate, where the EUV-active photoresist film is an organometallic oxide having polymerized carbon-carbon bonds, and patterning the EUV-active photoresist film using EUV lithography to form a patterned photoresist on the surface of the semiconductor substrate.

Description

[Technical Field]

[0001] This application claims priority to U.S. Provisional Patent Application No. 63 / 394,471, filed August 2, 2022, U.S. Provisional Patent Application No. 63 / 442,079, filed January 30, 2023, and U.S. Provisional Patent Application No. 63 / 456,343, filed March 31, 2023, each of which is entitled "Method of Forming Photosensitive Organometallic Oxides by Chemical Vapor Polymerization," the disclosures of which are expressly incorporated herein by reference in their entireties.

[0002] The present invention relates generally to extreme ultraviolet (EUV) lithography, and in particular embodiments to EUV-active films and methods for forming the same. [Background technology]

[0003] Generally, semiconductor devices such as integrated circuits (ICs) are fabricated by successively depositing and patterning layers of dielectric, conducting, and semiconducting materials across a semiconductor substrate to form a monolithically integrated network of electronic components and interconnect elements (e.g., transistors, resistors, capacitors, metal lines, contacts, and vias). Each successive technology node reduces costs by shrinking minimum feature sizes and roughly doubling component packing density.

[0004] A common patterning method is to use a photolithography process to expose a coating of photoresist on a target layer to a pattern of actinic radiation, and then transfer the relief pattern to an underlying hard mask layer formed on the target layer or the target. Using this technique, the minimum feature size is limited by the resolution of the optical system. Feature size scaling in advanced technology nodes is driving lithography to improve resolution. For technology nodes below 10 nm (e.g., 7 nm and 5 nm technology nodes), 13.5 nm extreme ultraviolet (EUV) lithography is commonly used to pattern photoconductive films with EUV radiation.

[0005] EUV lithography technology offers significant advantages in patterning sub-10 nm features with its high optical resolution. However, one major engineering challenge of EUV lithography is that photoresists developed for conventional photolithography systems may not meet the cost and / or quality requirements for patterning sub-10 nm features. For example, chemically amplified resists (CARs) or similar polymer resists commonly used in 193 nm lithography are typically fabricated using liquid-based spin-on techniques, which consume significant amounts of complex metal cluster precursors and result in very high costs. CARs also tend to have low absorption coefficients at 13.5 nm and therefore may suffer from poor sensitivity. Furthermore, diffusion of photoactive species in CARs can cause blurring in subsequently formed patterns and increased line edge roughness (LER).

[0006] As an alternative to CAR, deposited metal oxide-containing films have been investigated for use as EUV-active hard masks in EUV lithography techniques. For example, U.S. Patent No. 9,996,004, entitled "EUV Photopatterning of Vapor-Deposited Metal Oxide-Containing Hardmasks," describes various processes for forming metal oxide-containing hard masks for use in EUV patterning. In the '004 patent, EUV-sensitive metal oxide-containing films are vapor-deposited onto semiconductor substrates by chemical vapor deposition (CVD) or atomic layer deposition (ALD). During the vapor deposition process, organotin oxide precursors are reacted with a carbon dioxide-containing plasma at relatively high vapor deposition temperatures (e.g., 250°C to 350°C) to vapor-deposit the EUV-sensitive metal oxide-containing films onto semiconductor substrates. After CVD / ALD vapor deposition, the metal oxide-containing film is transferred to an EUV patterning tool and patterned by direct EUV exposure (i.e., without the use of a photoresist), followed by pattern development to form a metal oxide-containing hard mask. The process described in the '004 patent suffers from various drawbacks. For example, the deposition process described in the '004 patent involves reacting various organotin oxide precursors with an oxidizing agent (e.g., carbon dioxide or carbon monoxide) in a typical CVD / ALD process to form a solid metal oxide-containing film on a semiconductor substrate. The oxidizing agent utilized in the CVD / ALD deposition process increases the density of the metal oxide-containing film and breaks Sn-R bonds (wherein -R is -CxHy, -OCxHy, -Cl, or -NCxHy) in the organotin precursor, creating weak and unstable bonds (e.g., Sn-OH and Sn-O-Sn bonds), which worsens the EUV light sensitivity of the subsequently formed hard mask. Summary of the Invention [Problem to be solved by the invention]

[0007] Innovations in EUV photolithography technology are needed to meet the cost and quality requirements for patterning in the sub-10 nm node region, and to meet these needs, it would be desirable to develop a new class of photoresists for EUV lithography with better performance. [Means for solving the problem]

[0008] The present disclosure provides improved processes and methods for forming EUV-active photoresist films containing organometallic oxides polymerized through carbon-carbon bonds. The present disclosure utilizes chemical vapor polymerization (CVP) to deposit a non-solid organometallic oxide polymer layer on the surface of a semiconductor substrate. In some embodiments of the present disclosure, the non-solid organometallic oxide polymer layer can be deposited on the substrate surface by a low-temperature, low-ion energy plasma process, which exposes the substrate surface to a plasma-excited vapor containing a metal precursor having carbon-carbon double bonds. The low-temperature, low-ion energy plasma process forms a non-solid organometallic oxide polymer layer (comprising liquid oligomeric units) having carbon-carbon bonds on the substrate surface. The semiconductor substrate is then subjected to a thermal treatment (e.g., a thermal bake) to further polymerize the non-solid organometallic oxide polymer layer and form an organometallic oxide polymer film having carbon-carbon bonds, which forms the EUV-active photoresist film.

[0009] The processes and methods disclosed herein offer various advantages over conventional methods of forming EUV-active photoresist films. For example, the disclosed methods provide EUV-active photoresists with higher EUV absorbance, better photoresist sensitivity, and better etch resistance compared to conventional chemically amplified resists (CARs). In some embodiments, the higher EUV absorbance may advantageously allow for a reduction in the thickness of the EUV-active photoresist required for acceptable performance. Compared to conventional metal oxide resists, the disclosed methods provide EUV-active photoresists with greater mechanical strength and photosensitivity.

[0010] According to one embodiment, a method for processing a semiconductor substrate is provided herein. The method may generally begin by forming an extreme ultraviolet (EUV)-active photoresist film on a surface of the semiconductor substrate, the EUV-active photoresist film comprising an organometallic oxide having polymerized carbon-carbon bonds. In some embodiments, the organometallic oxide may comprise a central metal atom selected from the group consisting of tin (Sn), zirconium (Zr), indium (In), antimony (Sb), bismuth (Bi), zinc (Zn), hafnium (Hf), aluminum (Al), and combinations thereof. In an exemplary embodiment, the organometallic oxide may comprise tin (Sn). After the EUV-active photoresist film is formed, the method may further include patterning the EUV-active photoresist film using EUV lithography to form a patterned photoresist on the surface of the semiconductor substrate.

[0011] In some embodiments, an EUV-active photoresist film can be formed by (a) exposing a surface of a semiconductor substrate to a plasma-excited vapor containing a metal precursor having a carbon-carbon double bond to form a non-solid organometallic oxide polymer layer on the surface of the semiconductor substrate, and (b) heat-treating the semiconductor substrate to further polymerize the non-solid organometallic oxide polymer layer and form an organometallic oxide having a polymerized carbon-carbon bond.

[0012] In some embodiments, exposing the surface of the semiconductor substrate to the plasma-excited vapor may be performed without exposing the substrate to an oxidizing agent, such as oxygen (O), ozone (O), water (HO), hydrogen peroxide (HO), carbon dioxide (CO), or carbon monoxide (CO). In some embodiments, exposing the surface of the semiconductor substrate to the plasma-excited vapor may be performed at a relatively low ion energy (e.g., less than 50 eV, and in some embodiments, from about 0 eV to about 5 eV) and a relatively low substrate temperature (e.g., less than about 100°C, and in some embodiments, from about -50°C to about 0°C). In such embodiments, the non-solid organometallic oxide polymer layer formed on the substrate surface may include liquid oligomeric units having carbon-carbon bonds.

[0013] In some embodiments, heat treating the semiconductor substrate can include maintaining the semiconductor substrate at a substrate temperature of about 0° C. to about 200° C. In other embodiments, heat treating the semiconductor substrate can include maintaining the semiconductor substrate at a substrate temperature of about 200° C. to about 400° C. During the heat treating step, the liquid oligomeric units having carbon-carbon bonds polymerize to form an organometallic oxide having polymerized carbon-carbon bonds.

[0014] According to another embodiment, another method for processing a semiconductor substrate is provided herein. The method may generally begin by exposing a surface of the semiconductor substrate to a plasma-excited vapor containing a metal precursor having a carbon-carbon double bond to form a non-solid organometallic oxide polymer layer on the surface of the semiconductor substrate. During the aforementioned exposure, the semiconductor substrate is maintained at a first substrate temperature of about −50° C. to about 0° C. The method may further include heat-treating the semiconductor substrate at a second substrate temperature of about 0° C. to about 400° C. to further polymerize the non-solid organometallic oxide polymer layer and form an organometallic oxide having polymerized carbon-carbon bonds. In some embodiments, the second substrate temperature may be about 0° C. to about 200° C. In other embodiments, the second substrate temperature may be about 200° C. to about 400° C. The organometallic oxide formed as a result of the exposure and heat-treating steps is an extreme ultraviolet (EUV) active photoresist film. The method may then include patterning the EUV active photoresist film using EUV lithography to form a patterned photoresist on the surface of the semiconductor substrate.

[0015] The methods described herein may utilize a variety of metal precursors. For example, the metal precursor may include a metal alkoxide. In some embodiments, the metal precursor may include tin (Sn) and may be represented by the formula Sn α O β (OC m H n )ΓC x H y (wherein m, n, and α are any integers equal to or greater than 1, β, Γ, x, and y are any integers equal to or greater than 0, and β and Γ are not simultaneously equal to 0). In one example, the metal precursor can include SnR1(O-R2)3, SnR12(O-R2)2, or SnHR1(O-R2)2 (wherein R1: CH3, C2H3, C3H5, C4H7, or C6H6 and R2: CH3, C2H5, C3H7, or C4H9). In another example, the metal precursor can include SnCH3 t Bu(O- t Bu)2, Sn t Bu(O- t Bu)3, Sn t Bu(O-C3H7)3, Snt Bu(O-C2H5)3, Sn t Bu(O-CH3)3, SnCH3C2H3(O- t In other embodiments, the metal precursor may include tin (Sn) and may have the formula Sn x C y H z where x, y, and z are any integers equal to or greater than 1. For example, the metal precursor may be selected from the group consisting of Sn(CH3)4, Sn(C2H5)4, SnH(CH3)3, and SnH(C2H5)3. In further embodiments, the metal precursor may include a metal (M) and have the formula M α O β (OC m H n )ΓC x H y (wherein m, n, and α are any integers equal to or greater than 1, β, Γ, x, and y are any integers equal to or greater than 0, and β and Γ are not simultaneously 0).

[0016] In some embodiments, the plasma-excited vapor may further include additional precursors. For example, the metal precursor may include tin (Sn) and have the formula Sn α O β (OC m H n )ΓC x H y In the case of a compound having the formula Sn, an additional precursor added to the plasma excited vapor may contain tin (Sn) and have the formula Sn α C x H y wherein m, n, and α are any integers equal to or greater than 1. The metal precursor may comprise a metal (M) and have the formula M α O β (OC m H n )ΓC x H y where m, n, and a are any integers equal to or greater than 1, then the additional precursor added to the plasma excited vapor may include a metal (M) and have the formula MαCxHy.

[0017] In some embodiments, the plasma-excited vapor can further include an additional monomer to increase the sensitivity of the EUV-active photoresist film to EUV radiation. In some embodiments, the additional monomer can include a hydrocarbon containing a carbon-oxygen double bond. For example, the additional monomer can include a ketone, an aldehyde, or an ester.

[0018] Various embodiments of methods for processing semiconductor substrates, and more particularly for forming EUV-active photoresist films comprising organometallic oxides polymerized through carbon-carbon bonds, are provided herein. It should be understood that the order of description of the various steps described herein is presented for clarity of explanation. In general, these steps may be performed in any suitable order. In addition, although various features, techniques, configurations, etc. described herein may be described in separate sections of this disclosure, it is understood that each concept may be implemented independently of one another or in combination with one another. Accordingly, the present invention may be embodied and viewed in many different ways.

[0019] It should be noted that this Summary section does not specify every embodiment and / or inherently novel aspect of the present disclosure or claimed invention. Rather, this Summary merely provides a preliminary discussion of various embodiments and corresponding aspects that are novel over the prior art. For additional details and / or anticipated aspects of the invention and embodiments, the reader is referred to the Detailed Description section and corresponding drawings of the present disclosure as further discussed below.

[0020] A more detailed understanding of the present invention and its advantages can be obtained by reference to the following description in conjunction with the accompanying drawings, in which like reference numerals indicate like features, and in which it should be noted, however, that the accompanying drawings illustrate only exemplary embodiments of the disclosed concepts and do not limit the scope of the present invention, as the disclosed concepts may encompass other embodiments that are equally effective. [Brief explanation of the drawings]

[0021] [Figure 1A] FIG. 1 is a process flow diagram illustrating an exemplary process flow for forming an EUV active photoresist film on a surface of a semiconductor substrate according to one embodiment of the present disclosure. [Figure 1B] Exemplary chemistries that can be utilized in the chemical vapor polymer deposition and thermal treatment steps shown in FIG. 1A are shown, including exemplary metal precursors that can be used during a plasma processing step to form exemplary non-solid organometallic oxide polymer layers on a substrate surface, and exemplary EUV-active photoresist films that can be formed during a subsequent thermal treatment step. [Figure 2A] FIG. 1B is a process flow diagram illustrating an exemplary process flow for patterning and developing the EUV-active photoresist film formed in FIG. 1A. [Figure 2B] 2B illustrates exemplary reactions that occur during the EUV exposure step and (optional) post-exposure bake (PEB) step shown in FIG. 2A. [Figure 3] FIG. 1 is a flow chart diagram illustrating one embodiment of a method for processing a semiconductor substrate according to the present disclosure. [Figure 4] FIG. 10 is a flow chart diagram illustrating another embodiment of a method for processing a semiconductor substrate according to the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0022] FIELD OF THE DISCLOSURE The present disclosure relates to photolithography processes, and more particularly to methods of forming extreme ultraviolet (EUV) active photoresists containing organometallic moieties for use in EUV photolithography processes.

[0023] Embodiments of the present disclosure provide an improved process flow and method for forming an EUV-active photoresist film containing an organometallic oxide polymerized through carbon-carbon bonds. The present disclosure utilizes chemical vapor polymerization (CVP) to deposit a non-solid organometallic oxide polymer layer on the surface of a semiconductor substrate. In some embodiments, the non-solid organometallic oxide polymer layer can be deposited on the substrate surface by a low-temperature, low-ion energy plasma process, which exposes the substrate surface to a plasma-excited vapor containing a metal precursor having carbon-carbon double bonds. The low-temperature, low-ion energy plasma process forms a non-solid organometallic oxide polymer layer (comprising liquid oligomeric units) having carbon-carbon bonds on the substrate surface. The semiconductor substrate is then subjected to a thermal treatment (e.g., a thermal bake) to further polymerize the non-solid organometallic oxide polymer layer and form an organometallic oxide polymer film having carbon-carbon bonds. In various embodiments, the organometallic oxide polymer film is responsive to EUV exposure, which induces a change in material properties that allows portions of the organometallic oxide polymer film to be removed during a subsequent patterning and development step, forming a patterned photoresist on the surface of the semiconductor substrate.

[0024] The methods described herein can be used to produce carbon-carbon bond polymerized organometallic oxides as extreme ultraviolet (EUV)-active photoresists. The EUV-active photoresists disclosed herein offer various advantages over conventional photoresists used in EUV lithography. For example, the EUV-active photoresists disclosed herein have higher EUV absorbance compared to conventional chemically amplified resists (CARs), thereby providing better resist sensitivity. In some embodiments, the higher EUV absorbance can reduce the photoresist thickness required for acceptable performance. The EUV-active photoresists described herein may also have the advantage of exhibiting better etch resistance than conventional CARs. Additionally, the methods herein can provide a uniform chemical composition for the EUV-active photoresist, which can be beneficial in reducing issues with blurring or line edge roughness.

[0025] Furthermore, EUV-active photoresists according to various embodiments of the present disclosure can be formed on a substrate and developed by dry or wet processes. While conventional techniques used to apply and develop CARs are based on wet processes, the dry processes for forming and developing EUV-active photoresists disclosed herein provide better process control at the nanoscale than wet processes (e.g., when forming features with critical dimensions of a few nanometers or less). While dry processes are preferred, conventional spin-on processes for deposition and wet processes using developers can also be used with the methods of the present disclosure.

[0026] In addition to the CAR, the EUV-active photoresists disclosed herein offer various advantages over conventionally deposited metal oxide-containing films, such as those described in the '004 patent. Unlike the conventional process disclosed in the '004 patent, which involves reacting various organotin oxide precursors with an oxidizing agent (e.g., carbon dioxide or carbon monoxide) to form a solid metal oxide-containing film on a semiconductor substrate in a typical CVD / ALD process, the improved process flow and method disclosed herein uses a low-temperature, low-ion energy plasma process that exposes the substrate surface to a plasma-excited vapor containing a metal precursor having a carbon-carbon double bond to deposit a non-solid organometallic oxide polymer layer (comprising liquid oligomeric units) having carbon-carbon bonds on the substrate surface. The carbon-carbon double bonds present in the metal precursor promote polymerization during a subsequent thermal treatment step, forming an organometallic oxide polymer film having carbon-carbon bonds. The presence of carbon-carbon bonds in organometallic oxide polymer films increases the mechanical strength and stability of the EUV-active photoresists disclosed herein compared to conventionally deposited metal oxide-containing films containing Sn—OH and Sn—O—Sn bonds.

[0027] Referring now to the drawings, FIG. 1A illustrates one embodiment of a process flow 100 used to form an EUV-active photoresist on a surface of a semiconductor substrate in accordance with one embodiment of the present disclosure. As shown in FIG. 1A, the process flow 100 begins by performing a low-temperature, low-ion energy plasma process 120 that exposes the surface of the semiconductor substrate 110 to a plasma-excited vapor 125 containing a metal precursor having a carbon-carbon double bond. In some embodiments, additional precursors may also be included in the plasma-excited vapor 125. Examples of suitable metal precursors and additional precursors are described in further detail below. During the plasma process 120, the semiconductor substrate 110 is maintained at a relatively low substrate temperature (e.g., a substrate temperature below about 100° C., more preferably below about 0° C.), while the ions in the plasma-excited vapor 125 are maintained at a relatively low ion energy (e.g., an ion energy of less than about 50 eV, more preferably between about 0 eV and about 5 eV). Under these conditions, a non-solid organometallic oxide polymer layer 135 is deposited on the surface of the semiconductor substrate 110 by chemical vapor phase polymerization (CVP) 130 .

[0028] Once the non-solid organometallic oxide polymer layer 135 is deposited on the substrate surface, the semiconductor substrate 110 is subjected to a thermal treatment 140 (e.g., a thermal bake) to further polymerize the non-solid organometallic oxide polymer layer 135 and form an organometallic oxide polymer film 145 having carbon-carbon bonds on the substrate surface. The organometallic oxide polymer film 145 formed according to process flow 100 is an EUV-active photoresist film that can be patterned and developed using EUV lithography, for example, as shown in FIG. 2A and described below.

[0029] As described above, the plasma process 120 shown in FIG. 1A is performed at a relatively low substrate temperature and ion energy. According to one embodiment, the substrate temperature during plasma exposure can be, for example, less than about 100° C. In other embodiments, the substrate temperature during plasma exposure can be about −50° C. to about 0° C., about −50° C. to about −25° C., or about −25° C. to about 0° C. According to one embodiment, the ion energy of the ions in the plasma-excited vapor 125 can be about 50 eV. In other embodiments, the ion energy can be less than 50 eV, for example, about 0 eV to about 50 eV, or about 0 eV to about 5 eV. The use of an ion energy of about 0 eV to about 5 eV is believed to be beneficial for minimizing plasma damage to the non-solid organometallic oxide polymer layer 135 deposited on the substrate surface during the plasma process 120.

[0030] The plasma process 120 shown in FIG. 1A can be performed in a variety of plasma processing systems and / or chambers. In some embodiments, the plasma process 120 can be performed in a capacitively coupled plasma (CCP) processing chamber. In some examples, a 13.56 MHz to 60 MHz CCP source with a power of about 10 W to about 500 W can be used to generate plasma conditions including ion energies of about 50 eV (or less). The gas pressure in the CCP processing chamber can be, for example, about 100 mTorr to about 20 mTorr. The substrate temperature, as described above, can be less than about 100°C.

[0031] In other embodiments, the plasma process 120 shown in FIG. 1A can be performed using a plasma processing system including a remote plasma source. Examples of such plasma processing systems include the use of remote plasma sources that use radio frequency (RF), very high frequency (VHF), and microwave frequency (MWF). A plasma processing system including a remote plasma source can include (a) a vacuum chamber divided into a plasma space and a separate wafer space by a separator plate with multiple holes, or (b) a plasma source attached to the vacuum chamber. A remote plasma source can be desirable in some embodiments because it is effective in minimizing or eliminating exposure of the substrate to high-energy ions.

[0032] The thermal treatment 140 shown in FIG. 1 involves thermally treating the semiconductor substrate 110, including the non-solid organometallic oxide polymer layer 135 formed thereon, to further polymerize the non-solid organometallic oxide polymer layer 135 and form an organometallic oxide having polymerized carbon-carbon bonds. A variety of methods can be utilized to thermally treat the semiconductor substrate 110. According to one embodiment, the thermal treatment 140 can be performed in a vacuum chamber at an elevated substrate temperature. In such an embodiment, the thermal treatment can be performed under reduced pressure in the presence of an additional gas, which can include, for example, hydrogen bromide (HBr), hydrogen (H), helium (He), argon (Ar), neon (Ne), xenon (Xe), nitrogen (N), and / or carbon monoxide (CO). In one example, the thermal treatment can be performed using a substrate holder functioning as a hot plate. Furthermore, the thermal treatment can be performed without plasma excitation or with plasma excitation of an additional gas. In another example, the thermal treatment can be performed by optical means, such as laser heating. According to one embodiment, the substrate temperature during the thermal treatment 140 step can be from about 0°C to about 400°C. In other embodiments, the substrate temperature during the thermal treatment 140 step can be from about 0°C to about 50°C, from about 50°C to about 100°C, from about 100°C to about 200°C, from about 200°C to about 300°C, from about 0°C to about 200°C, or from about 200°C to about 400°C. Other methods for performing the polymerization shown in FIG. 1A include, but are not limited to, the use of a hot filament on the substrate or activation with an electron beam, UV, EUV, high NA EUV, or next generation high NA / hyper NA EUV.

[0033] During the plasma process 120 shown in FIG. 1A , various metal precursors can be used to form an EUV-active photoresist film. For example, a metal precursor including an EUV metal can be used. In this disclosure, the term “EUV metal” can refer to a metal component having a high EUV absorption coefficient. According to one embodiment, the EUV metal can include tin (Sn). In other embodiments, the EUV metal can include zirconium (Zr), indium (In), antimony (Sb), bismuth (Bi), hafnium (Hf), or aluminum (Al). According to one embodiment, the organometallic oxide of the EUV-active photoresist film includes a central metal atom selected from the group consisting of tin (Sn), zirconium (Zr), indium (In), antimony (Sb), bismuth (Bi), zinc (Zn), hafnium (Hf), aluminum (Al), and combinations thereof. In the following description, various embodiments, including the figures, are described using tin (Sn) as an exemplary metal component of the EUV-active photoresist film. However, it is recognized that the metal component is not limited to tin (Sn) and that other metals may also be present in the EUV-active photoresist film.

[0034] According to one embodiment, the metal precursor comprises tin (Sn) and has the formula Sn α O β (OC m H n )ΓC x H y (wherein m, n, and α are any integers equal to or greater than 1, β, Γ, x, and y are any integers equal to or greater than 0, and β and Γ are not simultaneously equal to 0). Examples include SnR1(O-R2)3, SnR12(O-R2)2, and SnHR1(O-R2)2 (wherein R1: CH3, C2H3, C3H5, C4H7, or C6H6, and R2: CH3, C2H5, C3H7, or C4H9). Further examples of metal precursors containing tin (Sn) include SnCH3 t Bu(O- t Bu)2, Sn t Bu(O- t Bu)3, Sn t Bu(O-C3H7)3, Sn t Bu(O-C2H5)3, Snt Bu(O-CH3)3, SnCH3C2H3(O- t Examples of tin (Sn)-containing metal precursors include Sn(C2H4O2) and Sn(OR)2, where R can be selected from CH3, C2H5, and C4H9. Still other examples include a mixture of Sn(N(CH3)2)4 and HOCH2CH2OH.

[0035] According to another embodiment, the metal precursor comprises tin (Sn) and has the formula Sn x C y H z where x, y, and z are any integers equal to or greater than 1. In one example, the metal precursor is selected from the group consisting of Sn(CH), Sn(C,H), SnH(CH,), and SnH(C,H). In such an embodiment, the plasma-excited vapor 125 containing the metal precursor may further include an additional gas such as, but not limited to, hydrogen (H), helium (He), argon (Ar), neon (Ne), krypton (KR), nitrogen (N), or acetylene (C,H).

[0036] According to yet another embodiment, the metal precursor comprises a metal (M) and has the formula M α O β (OC m H n )ΓC x H y (wherein m, n, and α are any integers equal to or greater than 1, β, Γ, x, and y are any integers equal to or greater than 0, and β and Γ are not simultaneously equal to 0.) Examples of metals with high EUV absorption coefficients include, but are not limited to, tin (Sn), zirconium (Zr), antimony (Sb), indium (In), bismuth (Bi), zinc (Zn), hafnium (Hf), and aluminum (Al).

[0037] In some embodiments, the plasma-excited vapor 125 can include a metal precursor and an additional precursor. For example, the metal precursor can include tin (Sn) and have the formula Sn α Oβ (OC m H n )ΓC x H y , the additional precursor added to the plasma excited vapor 125 may include tin (Sn) and have the formula Sn α C x H y wherein m, n, and α are any integers equal to or greater than 1. The metal precursor may comprise a metal (M) and have the formula M α O β (OC m H n )ΓC x H y , the additional precursor added to the plasma excited vapor 125 may include a metal (M) and may have the formula MαCxHy, where m, n, and α are any integers equal to or greater than 1.

[0038] According to one embodiment, the sensitivity of the EUV-active photoresist film to EUV radiation can be amplified with additional monomers by introducing species having a carbon-oxygen double bond (C=O) surrounding the organometallic oxide. According to one embodiment, the plasma-excited vapor 125 can further include additional monomers, such as hydrocarbons containing a C=O bond. For example, the plasma-excited vapor 125 can further include additional monomers, such as ketones, aldehydes, or esters, each of which contains a carbonyl group having a carbon-oxygen double bond (C=O). The ketones can be selected from the group consisting of acetone, methyl ethyl ketone, methyl propyl ketone, and methyl isopropyl ketone. The aldehydes can be selected from the group consisting of formaldehyde, acetaldehyde, and propionaldehyde. The esters can be selected from the group consisting of ethyl methanoate, methyl acetate, ethyl acetate, methyl acrylate, methyl butanoate, and methyl salicylate.

[0039] According to one embodiment, the plasma-excited vapor 125 may include a metal precursor including tin (Sn), and the additional monomer may include a ketone, an aldehyde, or an ester. According to one embodiment, the plasma-excited vapor 125 may further include an additional gas, such as, but not limited to, hydrogen (H), helium (He), argon (Ar), neon (Ne), xenon (Xe), nitrogen (N), carbon monoxide (CO), ammonia (NH), or hydrogen sulfide (HS).

[0040] 1A, including an exemplary metal precursor 127 that can be used in plasma process 120 to form an exemplary non-solid organometallic oxide polymer layer 135 on the surface of semiconductor substrate 110. In FIG. 1B, metal precursor 127 is an organotin compound containing a carbon-carbon double bond 129. Plasma excitation of the organotin compound affects the carbon-carbon double bond 129 to form non-solid organometallic oxide polymer layer 135 on the surface of semiconductor substrate 110. In some embodiments, the plasma excitation can include an additional gas, such as, for example, hydrogen (H), helium (He), argon (Ar), neon (Ne), krypton (Kr), nitrogen (N), acetylene (C2H2), or carbon monoxide (CO).

[0041] FIG. 1B schematically illustrates two alkoxide-based metal precursor molecules being plasma-excited in the absence of an oxidizing agent, such as oxygen (O), ozone (O), water (HO), hydrogen peroxide (HO), carbon dioxide (CO), or carbon monoxide (CO), to form a non-solid organometallic oxide polymer layer 135 on the surface of a semiconductor substrate 110. The plasma-based reaction forms liquid oligomeric units 137 of an organometallic oxide on the substrate surface. A subsequent thermal treatment (e.g., thermal bake) can be used to further polymerize the liquid oligomeric units 137 of the non-solid organometallic oxide polymer layer 135 to form an organometallic oxide polymer film 145. For example, as shown schematically in FIG. 1B, the liquid oligomeric units 137 of the non-solid organometallic oxide polymer layer 135 polymerize during the thermal treatment to form an organometallic oxide having polymerized carbon-carbon bonds.

[0042] Chemical vapor polymerization (CVP), shown in Figures 1A and 1B, i.e., plasma excitation of organotin compounds followed by thermal treatment of the semiconductor substrate, forms organometallic oxides with polymerized carbon-carbon bonds, which improve the mechanical strength and photosensitivity of EUV-active photoresist films.

[0043] In the exemplary chemical reaction shown in FIG. 1B, the organotin compound is C m H n It contains Sn-O- units protected by ligands (e.g., methane (CH3) and ethyl radicals (C2H5)). m H n The ligands create carbon-carbon bonds to improve the stability and strength of the film. The CmHn ligands also prevent Sn-O-Sn bonds in a given polymer molecule from bonding with other Sn-O-Sn bonds in other polymer molecules of the subsequently formed film. In another aspect, C m H nThe ligands promote solubility of the portions of the EUV-active photoresist that are subsequently removed (e.g., in the non-EUV-exposed areas) during a subsequent development step. Additionally, the organotin compounds containing carbon-carbon double bonds 129 promote polymerization during a thermal treatment 140 step to form an organometallic oxide polymer film 145 having a polymerized carbon-carbon backbone 146, enhancing the mechanical strength and photosensitivity of the EUV-active photoresist film. In some embodiments, the photosensitivity of the EUV-active photoresist film can be increased by adding a monomer to the plasma-excited vapor 125 (not shown in FIG. 1B ), where the additional monomer has a carbon-oxygen double bond (C═O) surrounding the organometallic oxide.

[0044] Figure 2A illustrates one embodiment of a process flow 200 used to pattern and develop an EUV-active photoresist film, such as the EUV-active photoresist film formed in Figure 1 A. Figure 2B schematically illustrates exemplary reactions that may occur during the EUV lithography process and (optional) thermal treatment step shown in Figure 2A.

[0045] As shown in FIG. 2A , the EUV lithography process can be performed by exposing the surface of the semiconductor substrate 110, including the EUV-active photoresist film (i.e., organometallic oxide polymer film 145), to EUV radiation 155 (e.g., at a wavelength of 13.5 nm) in an EUV exposure 150 step. The EUV lithography process can utilize a photomask (not shown) so that the photo-induced reaction occurs only in the regions 147 of the EUV-active photoresist exposed to the EUV radiation 155. The regions of the EUV-active photoresist 147 exposed to the EUV radiation 155 are converted to a reacted photoresist. The regions of the EUV-active photoresist 149 not exposed to the EUV radiation 155 remain unreacted. After the EUV exposure 150 step, an optional thermal treatment step (e.g., a post-exposure bake (PEB)) 160 can be performed to complete the reaction initiated during the exposure, thereby stabilizing the EUV-exposed photoresist and promoting -(Sn-O-)n cross-linking in the EUV-exposed regions. In some embodiments, the optional heat treatment step 160 can prevent changes in line edge roughness (LER), line width roughness (LWR) and / or critical dimension (CD).

[0046] After the EUV exposure 150 and optional post-exposure bake (PEB) 160 are completed, a development step 170 can be performed to remove portions of the EUV-active photoresist for patterning, thereby resulting in patterned photoresist 175 on the substrate surface. The development step 170 can be a wet or dry process. Traditionally, portions of the EUV-active photoresist can be removed by treating the substrate with a developer to dissolve the reacted areas (in the case of a positive-tone resist) or unreacted areas (in the case of a negative-tone resist) of the EUV-active photoresist. Similar wet processes can be applied to various embodiments. Alternatively, in other embodiments, a dry process can be used to remove the reacted or unreacted areas of the EUV-active photoresist. The dry process can include, for example, a selective plasma etching process or a thermal process, advantageously eliminating the use of a developer solution. In certain embodiments, the dry process can be performed using a reactive ion etching (RIE) process or atomic layer etching (ALE).

[0047] FIG. 2B illustrates potential reactions that may occur during EUV exposure 150, with an optional thermal treatment step (post-exposure bake (PEB)) 160 shown in FIG. 2A. As shown in FIG. 2B, a first reaction 157 can occur during EUV exposure 150 to form metal (e.g., tin) alkoxide oligomers. As shown in FIG. 2B, during the EUV exposure 150 step, tin (Sn) atoms absorb EUV photons and emit secondary electrons to surrounding -C bonds, cleaving Sn-C, O-C bonds and thus forming Sn-H and Sn-OH bonds. During the optional PEB 160, the converted Sn-H and Sn-OH bonds form a larger network of stable Sn-O-Sn bonds in a second reaction 165.

[0048] 3 and 4 illustrate various embodiments of methods for processing a semiconductor substrate in accordance with the present disclosure. More specifically, FIGS. 3 and 4 illustrate various embodiments of methods that can be used to form an EUV-active photoresist film comprising a polymerized organometallic oxide with carbon-carbon bonds for use in an EUV photolithography process. It will be understood that the embodiments of FIGS. 3-4 are merely exemplary, and that additional methods may use the techniques described herein. Furthermore, the described processing steps are not intended to be exclusive, and additional steps may be added to the methods shown in FIGS. 3-4. Furthermore, the order of steps is not limited to the order shown in the figures, as different orders may occur and / or various steps may be combined or performed simultaneously.

[0049] FIG. 3 illustrates one embodiment of a method 300 for processing a semiconductor substrate. The method 300 illustrated in FIG. 3 may generally begin by forming (at step 310) an extreme ultraviolet (EUV)-active photoresist film on a surface of a semiconductor substrate. The EUV-active photoresist film formed in step 310 is an organometallic oxide having polymerized carbon-carbon bonds. In some embodiments, the organometallic oxide may include a central metal atom selected from the group consisting of tin (Sn), zirconium (Zr), indium (In), antimony (Sb), bismuth (Bi), zinc (Zn), hafnium (Hf), aluminum (Al), and combinations thereof. In an exemplary embodiment, the organometallic oxide may include tin (Sn). After the EUV-active photoresist film is formed in step 310, the method 300 may further include (at step 320) patterning the EUV-active photoresist film using EUV lithography to form a patterned photoresist on the surface of the semiconductor substrate.

[0050] In some embodiments, in step 310, the EUV-active photoresist film may be formed by (a) exposing the surface of the semiconductor substrate to a plasma-excited vapor containing a metal precursor having a carbon-carbon double bond to form a non-solid organometallic oxide polymer layer on the surface of the semiconductor substrate, and (b) heat-treating the semiconductor substrate to further polymerize the non-solid organometallic oxide polymer layer and form an organometallic oxide having a polymerized carbon-carbon bond.

[0051] In some embodiments, exposing the surface of the semiconductor substrate to plasma-excited vapor for polymerization of the organic polymer may be performed without exposing the substrate to an oxidizing agent such as oxygen (O), ozone (O), water (HO), hydrogen peroxide (HO), carbon dioxide (CO), or carbon monoxide (CO).

[0052] In some embodiments, exposing the surface of the semiconductor substrate to the plasma-excited vapor may be performed at a relatively low ion energy (e.g., less than 50 eV, more specifically, from about 0 eV to about 5 eV) and a relatively low substrate temperature (e.g., less than about 100°C, more specifically, from about -50°C to about 0°C). In such embodiments, the non-solid organometallic oxide polymer layer formed on the substrate surface may include liquid oligomeric units having carbon-carbon bonds.

[0053] In some embodiments, exposing the surface of the semiconductor substrate to the plasma-excited vapor may be performed at a relatively high reactive power. α O β (OC m H n )ΓC x H y When using organometallic precursors with saturated hydrocarbon ligands such as Sn (where y = 2x + 1), reducing the hydrogen partial pressure in the plasma-excited vapor promotes the polymerization of carbon-carbon (C-C) bonds to form organic films. The reactivity of the plasma-excited vapor is controlled by RF power. α O β (OC m H n )ΓC x Hy The precursor molecules are cleaved by highly reactive plasma-excited vapor to generate Sn-O-Sn bonds in the photoresist polymer with C-C bonds. The ratio of (-Sn-O-Sn-) / (-C-C-) improves the stability and mechanical strength of the organic resist film.

[0054] In some embodiments, heat treating the semiconductor substrate can include maintaining the semiconductor substrate at a substrate temperature of about 0° C. to about 200° C. In other embodiments, heat treating the semiconductor substrate can include maintaining the semiconductor substrate at a substrate temperature of about 200° C. to about 400° C. During the heat treating step, the liquid oligomeric units having carbon-carbon bonds polymerize to form an organometallic oxide having polymerized carbon-carbon bonds.

[0055] FIG. 4 illustrates another embodiment of a method 400 for processing a semiconductor substrate. The method 400 illustrated in FIG. 4 may generally begin by exposing (at step 410) a surface of the semiconductor substrate to a plasma-excited vapor containing a metal precursor having a carbon-carbon double bond to form a non-solid organometallic oxide polymer layer on the surface of the semiconductor substrate. During such exposure, the semiconductor substrate is maintained at a first substrate temperature of about −50° C. to about 0° C. The method 400 may further include (at step 420) thermally treating the semiconductor substrate at a second substrate temperature of about 0° C. to about 400° C. to further polymerize the non-solid organometallic oxide polymer layer and form an organometallic oxide having polymerized carbon-carbon bonds. The organometallic oxide formed in step 420 is an extreme ultraviolet (EUV)-active photoresist film. The method 400 may then include patterning the EUV-active photoresist film using EUV lithography to form a patterned photoresist on the surface of the semiconductor substrate.

[0056] The methods 300 and 400 shown in Figures 3-4 can utilize a variety of metal precursors in plasma-excited vapors. For example, the metal precursor can include a metal alkoxide. In some embodiments, the metal precursor includes tin (Sn) and has the formula Sn α O β (OC mH n )ΓC x H y (wherein m, n, and α are any integers equal to or greater than 1, β, Γ, x, and y are any integers equal to or greater than 0, and β and Γ are not simultaneously equal to 0). In one example, the metal precursor can include SnR1(O-R2)3, SnR12(O-R2)2, or SnHR1(O-R2)2 (wherein R1: CH3, C2H3, C3H5, C4H7, or C6H6, and R2: CH3, C2H5, C3H7, or C4H9). In another example, the metal precursor can include SnCH3 t Bu(O- t Bu)2, Sn t Bu(O- t Bu)3, Sn t Bu(O-C3H7)3, Sn t Bu(O-C2H5)3, Sn t Bu(O-CH3)3, SnCH3C2H3(O- t In other embodiments, the metal precursor may comprise tin (Sn) and have the formula Sn x C y H z where x, y, and z are any integers equal to or greater than 1. For example, the metal precursor may be selected from the group consisting of Sn(CH3)4, Sn(C2H5)4, SnH(CH3)3, and SnH(C2H5)3. In further embodiments, the metal precursor comprises a metal (M) and has the formula M α O β (OC m H n )ΓC x H y (wherein m, n, and α are any integers equal to or greater than 1, β, Γ, x, and y are any integers equal to or greater than 0, and β and Γ are not simultaneously 0).

[0057] In some embodiments, the plasma-excited vapor can include a metal precursor and an additional precursor. For example, the metal precursor can include tin (Sn) and have the formula Sn α O β (OC m H n )ΓC x H yIn the case of a compound having the formula Sn, an additional precursor added to the plasma excited vapor may contain tin (Sn) and have the formula Sn α C x H y wherein m, n, and α are any integers equal to or greater than 1. The metal precursor may comprise a metal (M) and have the formula M α O β (OC m H n )ΓC x H y where m, n, and a are any integers equal to or greater than 1, then the additional precursor added to the plasma excited vapor may include a metal (M) and have the formula MαCxHy.

[0058] In some embodiments, the plasma-excited vapor can further include an additional monomer to increase the sensitivity of the EUV-active photoresist film to EUV radiation. In some embodiments, the additional monomer can include a hydrocarbon containing a carbon-oxygen double bond. For example, the additional monomer can include a ketone, an aldehyde, or an ester.

[0059] Improved process flows and methods for forming EUV-active photoresist films containing organometallic oxides polymerized through carbon-carbon bonds for use in EUV photolithography processes are described in various embodiments. The process flows and methods disclosed herein improve upon conventional methods for forming EUV-active photoresists by utilizing chemical vapor polymerization (CVP) to deposit metal oxide resist complexes on substrate surfaces using a low-temperature, low-ion energy plasma process. The low-temperature, low-ion energy plasma process uses various metal precursors with carbon-carbon double bonds to form liquid oligomeric units on the substrate surface, which further polymerize upon thermal treatment to form novel organometallic compounds with improved mechanical strength and stability compared to conventional EUV-active photoresists. Using the process flows and methods disclosed herein, the novel organometallic compounds are formed with excellent uniformity and better nucleation on underlying surfaces, even hydrophobic surfaces. The process flows and methods disclosed herein also result in faster deposition on hydrophobic surfaces by depositing liquid oligomeric units on the substrate surface using CVP instead of depositing hard metal oxide films using conventional CVD or ALD. While the novel organometallic compounds described herein can be deposited at a variety of thicknesses (e.g., from less than 10 nm to hundreds of nm), the process flows and methods disclosed herein can enable the deposition of thinner, more uniform photoresist coatings on substrate surfaces, which can then be used to transfer sub-10 nm features into underlying layers of the substrate.

[0060] As used herein, the term "substrate" refers to and includes the basic material or structure upon which a material is formed. It will be understood that a substrate can include a single material, multiple layers of different materials, one or more layers having regions of different materials or structures therein, etc. These materials can include semiconductors, insulators, conductors, or combinations thereof. For example, a substrate can be a semiconductor substrate, a base semiconductor layer on a support structure, a metal electrode, or a semiconductor substrate having one or more layers, structures, or regions formed thereon. A substrate can be a conventional silicon substrate or other bulk substrate containing a layer of semiconducting material. As used herein, the term "bulk substrate" refers to and includes not only silicon wafers, but also silicon-on-insulator ("SOI") substrates such as silicon-on-sapphire ("SOS") substrates and silicon-on-glass ("SOG") substrates, epitaxial layers of silicon on a base semiconductor substrate, and other semiconductor or optoelectronic materials such as silicon germanium, germanium, gallium arsenide, gallium nitride, and indium phosphide. The substrate may be doped or undoped.

[0061] Substrate may also include any material portion or structure of a device, particularly a semiconductor device or other electronic device, and may be a base substrate structure such as a semiconductor substrate or a layer on or located on the base substrate structure. Thus, the term "substrate" is not intended to be limited to any base structure, underlying or overlying layer, patterned or unpatterned layer, but rather is intended to include any such layer or base structure and any combination of layers and / or base structures.

[0062] It should be noted that throughout this specification, references to "one embodiment" or "an embodiment" mean that a particular feature, structure, material, or characteristic described in connection with this embodiment is included in at least one embodiment of the invention, but do not mean that it is present in all embodiments. Thus, the appearances of the phrase "in one embodiment" or "in an embodiment" in various places throughout this specification do not necessarily refer to the same embodiment of the invention. Furthermore, particular features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments. In other embodiments, various additional layers and / or structures may be included and / or described features may be omitted.

[0063] Those skilled in the art will understand that various embodiments can be practiced without one or more of the specific details, or with other alternative and / or additional methods, materials, or components. In other instances, well-known structural, material, or operational details are not shown or described to avoid obscuring aspects of the various embodiments of the invention. Similarly, for purposes of explanation, specific numbers, materials, and configurations are set forth to provide a thorough understanding of the invention. Nevertheless, the invention can be practiced without the specific details. Furthermore, it should be understood that the various embodiments shown in the figures are illustrative representations and are not necessarily drawn to scale.

[0064] Further modifications and alternative embodiments of the methods described herein will be apparent to those skilled in the art in view of this description. Accordingly, it will be appreciated that the described methods are not limited by these exemplary configurations. It is understood that the forms of the methods shown and described herein should be construed as exemplary embodiments. Various changes in implementation may be made. Thus, although the invention is described herein with reference to specific embodiments, various modifications and changes may be made without departing from the scope of the invention. Accordingly, the specification and drawings should be regarded in an illustrative, rather than a restrictive, sense, and such modifications are intended to be included within the scope of the invention. Furthermore, benefits, advantages, or solutions to problems described herein with respect to particular embodiments are not intended to be construed as essential, required, or essential features or elements of the claims.

Claims

1. A method for processing semiconductor substrates, A step of forming an extreme ultraviolet (EUV) active photoresist film on the surface of the semiconductor substrate, wherein the EUV active photoresist film comprises an organometallic oxide having polymerized carbon-carbon bonds, and the step of forming the film is: A step of depositing a non-solid organometallic oxide polymer layer on the surface of the semiconductor substrate using chemical vapor deposition (CVP), and The process involves heat-treating the semiconductor substrate to further polymerize the non-solid organometallic oxide polymer layer, thereby forming the organometallic oxide having polymerized carbon-carbon bonds. A process having, A step of patterning the EUV-activated photoresist film using EUV lithography to form a patterned photoresist on the surface of the semiconductor substrate, A method having.

2. The method according to claim 1, wherein the organometallic oxide comprises a central metal atom of tin (Sn), zirconium (Zr), indium (In), antimony (Sb), bismuth (Bi), zinc (Zn), hafnium (Hf), or aluminum (Al) or a combination thereof.

3. The step of depositing the non-solid organometallic oxide polymer layer on the surface of the semiconductor substrate using chemical vapor deposition (CVP) is: The process of exposing the surface of the semiconductor substrate to a plasma-excited vapor containing a metal precursor having a carbon-carbon double bond to form the non-solid organometallic oxide polymer layer on the surface of the semiconductor substrate. The method according to claim 1, comprising:

4. The method according to claim 3, wherein the non-solid organometallic oxide polymer layer comprises liquid oligomer units having carbon-carbon bonds.

5. The step of exposing the surface of the semiconductor substrate to the plasma-excited vapor is performed by oxygen (O ２ ), ozone (O ３ ), water (H ２ O), hydrogen peroxide (H ２ O ２ ), carbon dioxide (CO2) ２ The method according to claim 3, which is carried out without exposure to ) or carbon monoxide (CO).

6. The method according to claim 3, wherein the metal precursor comprises a metal alkoxide.

7. The metal precursor contains tin (Sn) and has the general formula Sn α O β (O - C ｍ H ｎ )ΓC ｘ H ｙ where m, n, and α are any integers greater than or equal to 1, β, Γ, x, and y are any integers greater than or equal to 0, and β and Γ are not both 0 at the same time. The method according to claim 3.

8. The plasma-excited vapor further comprises an additional precursor, the additional precursor containing tin (Sn), and the general formula is Sn α C ｘ H ｙ The method according to claim 7, wherein m, n, and α are any integers of 1 or more.

9. The aforementioned metal precursor is SnR1(O-R2) ３ SnR1 ２ (O-R2) ２ , or SnHR1(O-R2) ２ It has, where R1:CH ３ , C ２ H ３ , C ３ H ５ , C ４ H ７ , or C ６ H ６ And R2:CH ３ , C ２ H ５ , C ３ H ７ , or C ４ H ９ The method according to claim 3.

10. The aforementioned metal precursor is SnCH ３ ｔ Bu(O- ｔ Bu) ２ Sn ｔ Bu(O- ｔ Bu) ３ Sn ｔ Bu(O-C) ３ H ７ ) ３ Sn ｔ Bu(O-C) ２ H ５ ) ３ Sn ｔ Bu(O-CH) ３ ) ３ SnCH ３ C ２ H ３ (O- ｔ Bu) ２ , or SnCH ３ (C ２ H ３ ) (O-CH ３ ) ２ The method according to claim 3, including the method described in claim 3.

11. The aforementioned metal precursor contains tin (Sn), and the general formula is Sn ｘ C ｙ H ｚ The method according to claim 3, wherein x, y, and z are any integers of 1 or more.

12. The aforementioned metal precursor is Sn(CH ３ ) ４ , Sn(C ２ H ５ ) ４ SnH(CH ３ ) ３ , or SnH(C ２ H ５ ) ３ The method according to claim 11, including the method described in claim 11.

13. The aforementioned metal precursor contains a metal (M), and the general formula is M α O β (O-C) ｍ H ｎ )ΓC ｘ H ｙ The method according to claim 3, wherein m, n, and α are any integers greater than or equal to 1, and β, Γ, x, and y are any integers greater than or equal to 0, and β and Γ are not both 0.

14. The method according to claim 13, wherein the plasma-excited vapor further comprises an additional precursor, the additional precursor comprising the metal (M) and having the general formula MαCxHy, where m, n, and α are any integers of 1 or more.

15. The plasma-excited vapor further contains an additional monomer, thereby enhancing the photosensitivity of the EUV-activated photoresist film to EUV radiation. The method according to claim 3, wherein the additional monomer comprises a hydrocarbon containing a carbon-oxygen double bond.

16. The method according to claim 15, wherein the additional monomer comprises a ketone, an aldehyde, or an ester.

17. The step of exposing the surface of the semiconductor substrate to the plasma-excited vapor is, A step of maintaining an ion energy of approximately 50 eV or less in the plasma-excited vapor, During the aforementioned exposure, the process involves maintaining a substrate temperature of less than approximately 100°C, The method according to claim 3, having the following characteristics.

18. The method according to claim 1, wherein the heat treatment step comprises a step of maintaining the semiconductor substrate at a substrate temperature between approximately 0°C and approximately 200°C.

19. The method according to claim 1, wherein the heat treatment step includes a step of maintaining the semiconductor substrate at a substrate temperature between approximately 200°C and approximately 400°C.

20. A method for processing semiconductor substrates, A step of forming a non-solid organometallic oxide polymer layer on the surface of a semiconductor substrate by exposing the surface of the semiconductor substrate to a plasma-excited vapor containing a metal precursor having a carbon-carbon double bond, wherein the semiconductor substrate is maintained at a first substrate temperature between approximately -50°C and approximately 0°C during the exposure step. A step comprising: heat-treating the semiconductor substrate at a second substrate temperature between approximately 0°C and approximately 400°C to further polymerize the non-solid organometallic oxide polymer layer, thereby forming an organometallic oxide having polymerized carbon-carbon bonds, wherein the organometallic oxide forms an extreme ultraviolet (EUV) active photoresist film. A step of patterning the EUV-activated photoresist film using EUV lithography to form a patterned photoresist on the surface of the semiconductor substrate, A method having.

21. The method according to claim 20, wherein the temperature of the second substrate is between approximately 0°C and approximately 200°C.

22. The method according to claim 20, wherein the second substrate temperature is between approximately 200°C and approximately 400°C.

23. The method according to claim 20, wherein the metal precursor comprises a metal alkoxide.

24. The plasma-excited vapor further contains an additional monomer, thereby enhancing the photosensitivity of the EUV-activated photoresist film to EUV radiation. The method according to claim 20, wherein the additional monomer comprises a hydrocarbon containing a carbon-oxygen double bond.

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