Method for manufacturing semiconductor device

Abstract

The present application relates to a method for manufacturing a semiconductor device, including forming a multilayer photoresist structure including a metal-containing photoresist above a substrate. The multilayer photoresist structure includes two or more metal-containing photoresist layers having different physical parameters. The metal-containing photoresist is a reaction product of a first precursor and a second precursor, and each layer of the multilayer photoresist structure is formed using different photoresist layer formation parameters. The different photoresist layer formation parameters are one or more selected from the group consisting of: a first precursor, an amount of the first precursor, a second precursor, an amount of the second precursor, a length of time for each photoresist layer formation operation, and a heating condition for the photoresist layer. The multilayer photoresist structure is selectively exposed to actinic radiation to form a latent pattern, and the latent pattern is developed by applying a developer to the selectively exposed multilayer photoresist structure to form a pattern.

Description

Technical Field

[0001] The present disclosure relates to a method for manufacturing a semiconductor device. Background Art

[0002] As consumer devices become smaller in response to consumer demand, the individual components of these devices must also decrease in size. Semiconductor devices that constitute the main components of devices such as mobile phones, computer tablets, etc. have been forced to become smaller and smaller, which in turn forces the individual devices within the semiconductor devices (e.g., transistors, resistors, capacitors, etc.) to decrease in size.

[0003] One enabling technology used in the manufacture of semiconductor devices is the use of photolithographic materials. Such materials are applied to the surface of the layer to be patterned and then exposed to energy that has itself been patterned. Such exposure changes the chemical and physical properties of the exposed areas of the photosensitive material. This modification, and the lack of modification in the unexposed areas of the photosensitive material, can be exploited to remove one area without removing another area.

[0004] However, as the size of individual devices decreases, the process window for lithographic processing becomes increasingly tighter. Thus, advances in the field of lithographic processing are necessary to maintain the ability to scale down devices, and further improvements are needed to meet the desired design standards so that the march toward smaller and smaller components can be maintained.

[0005] As the semiconductor industry has progressed to nanotechnology process nodes in pursuit of higher device density, higher performance and lower cost, there are challenges in reducing semiconductor feature size. Extreme ultraviolet lithography (EUVL) has been developed to form smaller semiconductor device feature sizes and increase device density on semiconductor wafers. In order to improve EUVL, it is necessary to increase wafer exposure throughput. Wafer exposure throughput can be improved by increasing exposure power or increasing resist photospeed. Summary of the invention

[0006] According to one embodiment of the present disclosure, there is provided a method for manufacturing a semiconductor device, comprising:

[0007] forming a multi-layer photoresist structure including a metal-containing photoresist over the substrate,

[0008] wherein the multilayer photoresist structure comprises two or more metal-containing photoresist layers having different physical parameters,

[0009] wherein the metal-containing photoresist is a reaction product of a first precursor and a second precursor, and

[0010] wherein different photoresist layer formation parameters are used to form each layer of the multi-layer photoresist structure,

[0011] wherein the different photoresist layer formation parameters are one or more selected from the group consisting of: a first precursor, an amount of the first precursor, a second precursor, an amount of the second precursor, a time length of each photoresist layer formation operation, and a heating condition of the photoresist layer;

[0012] selectively exposing the multilayer photoresist structure to actinic radiation to form a latent pattern; and

[0013] The latent pattern is developed by applying a developer to the selectively exposed multi-layer photoresist structure to form a pattern.

[0014] According to another embodiment of the present disclosure, there is provided a method for forming a pattern, comprising:

[0015] forming a first resist layer having first physical parameters on the substrate;

[0016] forming a second resist layer having a second physical parameter over the first resist layer, wherein the first physical parameter and the second physical parameter are different;

[0017] cross-linking the first resist layer and the second resist layer pattern by pattern; and

[0018] removing uncrosslinked portions of the first resist layer and the second resist layer to form patterns in the first resist layer and the second resist layer,

[0019] wherein the first resist layer and the second resist layer are reaction products of a first metal-containing precursor and a second precursor,

[0020] wherein the first resist layer and the second resist layer are formed using different resist layer formation parameters,

[0021] The different resist layer formation parameters are one or more selected from the group consisting of: a first metal-containing precursor, an amount of the first metal-containing precursor, a second precursor, an amount of the second precursor, a length of time for each resist layer formation operation, and heating conditions for the resist layer.

[0022] According to another embodiment of the present disclosure, there is provided a method for forming a pattern, comprising:

[0023] forming a first photoresist layer on the substrate by depositing a first photoresist composition in a first vapor deposition operation with first deposition parameters;

[0024] forming a second photoresist layer on the first photoresist layer by depositing a second photoresist composition in a second vapor deposition operation with second deposition parameters,

[0025] wherein the first deposition parameter is different from the second deposition parameter, and

[0026] wherein the first deposition parameter and the second deposition parameter are one or more selected from the group consisting of: the amount of the first photoresist composition, the amount of the second photoresist composition, the length of time of each photoresist layer forming operation, the pressure, the vapor flow rate, and the heating conditions of the photoresist layer;

[0027] selectively exposing the first photoresist layer and the second photoresist layer to actinic radiation to form a latent pattern; and

[0028] The latent pattern is developed by applying a developer to the selectively exposed first photoresist layer and the second photoresist layer to form a pattern. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The present disclosure will be best understood from the following detailed description when read in conjunction with the accompanying drawings. It is emphasized that, in accordance with standard practice in the industry, various features are not drawn to scale and are used for illustration purposes only. In fact, the size of the various features may be arbitrarily increased or reduced for clarity of discussion.

[0030] Figure 1 A process flow for manufacturing a semiconductor device according to an embodiment of the present disclosure is shown.

[0031] Figure 2 The process stages are shown in sequential operation according to one embodiment of the present disclosure.

[0032] Figure 3A and Figure 3B The process stages are shown in sequential operation according to one embodiment of the present disclosure.

[0033] Figure 4A and Figure 4B The process stages are shown in sequential operation according to one embodiment of the present disclosure.

[0034] Figure 5 The process stages are shown in sequential operation according to one embodiment of the present disclosure.

[0035] Figure 6 The process stages are shown in sequential operation according to one embodiment of the present disclosure.

[0036] Fig. 7A An organometallic precursor according to an embodiment of the present disclosure is shown. Figure 7B The reactions that the metal precursor undergoes as a result of exposure to actinic radiation are shown. Figure 7C Examples of embodiments of organometallic precursors according to embodiments of the present disclosure are shown.

[0037] Figure 8 A photoresist deposition apparatus according to some embodiments of the present disclosure is shown.

[0038] Fig. 9 The reaction that a photoresist layer undergoes due to exposure to actinic radiation and heat according to one embodiment of the present disclosure is shown.

[0039] Fig. 10A , 10B 10C and 10C illustrate sequential operations according to one embodiment of the present disclosure.

[0040] Fig.11A and 11B A table showing parameters of a photoresist layer having a multi-layer photoresist structure according to an embodiment of the present disclosure.

[0041] Fig. 12A , 12B 12C illustrate sequential operations according to one embodiment of the present disclosure.

[0042] Fig.13A , 13B 13C illustrate sequential operations according to one embodiment of the present disclosure.

[0043] Fig.14 The process stages are shown in sequential operation according to one embodiment of the present disclosure.

[0044] Fig.15A and 15B The process stages are shown in sequential operation according to one embodiment of the present disclosure.

[0045] Fig.16A and Fig. 16B The process stages are shown in sequential operation according to one embodiment of the present disclosure.

[0046] Fig.17 The process stages are shown in sequential operation according to one embodiment of the present disclosure.

[0047] Fig.18 The process stages are shown in sequential operation according to one embodiment of the present disclosure. DETAILED DESCRIPTION

[0048] It should be understood that the following disclosure provides many different embodiments or examples for realizing the different features of the present disclosure. Specific embodiments or examples of components and arrangements are described below to simplify the present disclosure. Of course, these are only examples and are not intended to be limiting. For example, the size of the element is not limited to the disclosed range or value, but may depend on the process conditions and / or the desired characteristics of the device. In addition, in the following description, forming a first feature above or on a second feature may include an embodiment in which the first feature and the second feature are formed to be in direct contact, and may also include an additional feature inserted between the first feature and the second feature, so that the first feature and the second feature may not be in direct contact. For simplicity and clarity, various features may be arbitrarily drawn in different proportions.

[0049] In addition, for ease of description, spatially relative terms such as "below", "below", "lower", "above", "upper", etc. may be used herein to describe the relationship of one element or feature as shown in the figure to another one or more elements or features. In addition to the orientation depicted in the figure, spatially relative terms are also intended to cover different orientations of the device in use or operation. The device can be oriented in other ways (rotated 90 degrees or in other orientations), and the spatially relative descriptors used in this article can be interpreted accordingly. In addition, the term "made of" can mean "including" or "consisting of".

[0050] Metal-containing photoresists are used in extreme ultraviolet lithography because metals have high EUV radiation absorption capabilities. However, metal-containing photoresist layers may outgas during processing, which can cause the quality of the photoresist layer to vary over time and may cause contamination, which can negatively affect lithography performance and increase defects.

[0051] In addition, uneven exposure of the photoresist (especially at the deeper part of the photoresist layer) may result in uneven crosslinking of the photoresist. Less light energy reaches the lower part of the photoresist layer, resulting in uneven exposure. Low exposure dose may result in increased line width roughness and reduced critical dimension uniformity. Low exposure dose and uneven exposure at the lower part of the photoresist may result in poor line width roughness (LWR). The low exposure dose at the lower part of the photoresist layer may result in a T-shaped top resist profile instead of a straight-edge resist profile. Due to the low exposure dose at the lower part of the photoresist layer, the crosslinking in the upper part of the photoresist layer may be greater than the crosslinking in the lower part of the photoresist layer. Therefore, when developing, a T-shaped top resist profile may be produced. The T-shaped top resist profile is a resist profile in which the resist portion at the upper part is wider than the resist portion below the upper part as seen in the cross-sectional view. A profile shaped like a capital letter T is an example of a T-shaped top resist profile.

[0052] In an embodiment of the present disclosure, the above problems are solved by forming a multilayer photoresist structure on a substrate, wherein the multilayer photoresist structure includes two or more photoresist layers with different physical parameters. In some embodiments, the multilayer photoresist structure includes three to five photoresist layers stacked on top of each other, wherein adjacent photoresist layers have different physical parameters.

[0053] Figure 1 1 shows a process flow 100 for manufacturing a semiconductor device according to an embodiment of the present disclosure. In some embodiments, in operation S110, a photoresist is coated on a surface of a layer to be patterned or a substrate 10 to form a multi-layer photoresist structure 15, such as Figure 2As shown. In some embodiments, the multilayer photoresist structure 15 includes 2 photoresist layers 15a, 15b, while in other embodiments, the multilayer photoresist structure 15 includes 3, 4, 5 or more photoresist layers. Then, in some embodiments, the multilayer photoresist structure 15 undergoes a first heating operation (or pre-exposure baking (or pre-exposure baking)) S120 of the photoresist composition. The multilayer photoresist structure 15 is heated at a temperature and time sufficient to cure the multilayer photoresist structure 15. In some embodiments, the multilayer photoresist structure 15 is heated to a temperature of about 50°C to about 200°C for about 10 seconds to about ten minutes. In other embodiments, the multilayer photoresist structure is heated to a temperature of about 100°C to about 150°C for about 1 minute to about 5 minutes. In some embodiments, the heating operation S120 is performed after each photoresist layer is formed. In some embodiments, the first heating operation S120 is not performed. If the heating operation is performed at a temperature or time less than the disclosed ranges, crosslinking may be insufficient and the LWR of the photoresist structure may be reduced. If the heating operation is performed at a temperature or time greater than these ranges, excessive crosslinking may occur and the LWR of the photoresist structure may be reduced.

[0054] In operation S130, the multilayer photoresist structure 15 is selectively exposed to actinic radiation 45 / 97 (see Figure 3A and Figure 3B ). In some embodiments, the multilayer photoresist structure 15 is selectively exposed to ultraviolet radiation. In some embodiments, the ultraviolet radiation is deep ultraviolet radiation (DUV). In some embodiments, the ultraviolet radiation is extreme ultraviolet (EUV) radiation. In some embodiments, the actinic radiation is an electron beam.

[0055] like Figure 3A As shown, in some embodiments, exposure radiation 45 passes through photomask 30 before irradiating multilayer photoresist structure 15. In some embodiments, the photomask has a pattern to be replicated in multilayer photoresist structure 15. In some embodiments, the pattern is formed by an opaque pattern 35 on photomask substrate 40. Opaque pattern 35 can be formed of a material that is opaque to ultraviolet radiation (e.g., chrome), while photomask substrate 40 is formed of a material that is transparent to ultraviolet radiation (e.g., fused silica).

[0056] In some embodiments, EUV lithography is used to perform selective exposure of the multilayer photoresist structure 15 to form exposed regions 50 and unexposed regions 52. In an EUV lithography operation, a reflective photomask 65 is used to form a patterned exposure light, such as Figure 3BAs shown. The reflective photomask 65 includes a low thermal expansion glass substrate 70, on which a reflective multilayer 75 of Si and Mo is formed. A capping layer 80 and an absorber layer 85 are formed on the reflective multilayer 75. A rear conductive layer 90 is formed on the back side of the low thermal expansion substrate 70. In EUV lithography, EUV radiation 95 is directed toward the reflective photomask 65 at an incident angle of about 6°. A portion 97 of the EUV radiation is reflected by the Si / Mo multilayer 75 toward the photoresist-coated substrate 10, while a portion of the EUV radiation incident on the absorber layer 85 is absorbed by the photomask. In some embodiments, additional optical devices including mirrors are provided between the reflective photomask 65 and the photoresist-coated substrate.

[0057] In some embodiments, exposure to radiation is performed by placing the photoresist-coated substrate in a lithography tool. The lithography tool includes a photomask 30 / 65, an optical device, an exposure radiation source that provides radiation 45 / 97 for exposure, and a movable stage for supporting and moving the substrate under the exposure radiation.

[0058] In some embodiments, optics (not shown) are used in the lithography tool to expand, reflect, or otherwise control the radiation 45 / 97 before or after it is patterned by the photomask 30 / 65. In some embodiments, the optics include one or more lenses, mirrors, filters, and combinations thereof to control the radiation 45 / 97 along the path of the optics.

[0059] In some embodiments, the radiation is electromagnetic radiation, such as g-line (wavelength of about 436 nm), i-line (wavelength of about 365 nm), ultraviolet radiation, far ultraviolet radiation, extreme ultraviolet radiation, electron beam, etc. In some embodiments, the radiation source is selected from the group consisting of: mercury vapor lamp, xenon lamp, carbon arc lamp, KrF excimer laser (wavelength of 248 nm), ArF excimer laser (wavelength of 193 nm), F2 excimer laser (wavelength of 157 nm) or CO2 laser excited Sn plasma (extreme ultraviolet, wavelength of 13.5 nm).

[0060] The amount of electromagnetic radiation can be characterized by a flux or dose, which is obtained by integrating the radiation flux over the entire exposure time. In some embodiments, a suitable radiation flux is about 1 mJ / cm 2 About 150mJ / cm 2 , in other embodiments, about 2 mJ / cm 2 About 100mJ / cm 2 , in other embodiments, about 3 mJ / cm 2 to about 50mJ / cm 2One of ordinary skill in the art will recognize that other ranges of radiant flux within the explicit ranges above are contemplated and within the present disclosure.

[0061] In some embodiments, selective or pattern-by-pattern exposure is performed by scanning an electron beam. With electron beam lithography, the electron beam induces secondary electrons, thereby changing the irradiated material. High resolution can be achieved using electron beam lithography and the metal-containing resists disclosed herein. The electron beam can be characterized by the energy of the beam, and in some embodiments, suitable energies are in the range of about 5V to about 200kV (kilovolts), and in other embodiments, in the range of about 7.5V to about 100kV. In some embodiments, the near-field corrected beam dose at 30kV is about 0.1μC / cm 2 to about 5μC / cm 2 In other embodiments, about 0.5 μC / cm 2 to about 1μC / cm 2 and in other embodiments, about 1 μC / cm 2 to about 100μC / cm 2 One of ordinary skill in the art can calculate corresponding doses at other beam energies based on the teachings herein, and will recognize that other ranges of electron beam performance within the explicit ranges above are contemplated and within the present disclosure.

[0062] The regions of the photoresist structure exposed to the radiation 50 undergo a chemical reaction that changes its solubility in a subsequently applied developer relative to the regions of the photoresist layer that were not exposed to the radiation 52. In some embodiments, the portions of the photoresist structure exposed to the radiation 50 undergo a reaction that renders the exposed portions more soluble in the developer. In other embodiments, the portions of the photoresist structure exposed to the radiation 50 undergo a cross-linking reaction that renders the exposed portions less soluble in the developer.

[0063] Next, in some embodiments, the multilayer photoresist structure 15 is subjected to a second heating (or post-exposure baking) in operation S140. In some embodiments, depending on the thickness of the photoresist layer and the desired degree of crosslinking, the multilayer photoresist structure 15 is heated to a temperature of about 50°C to about 250°C for about 20 seconds to about 10 minutes. In some embodiments, the multilayer photoresist structure 15 is heated to a temperature of about 100°C to about 200°C for about 1 minute to about 5 minutes. In some embodiments, the post-exposure baking further crosslinks the exposed portion 50 of the photoresist structure, thereby increasing the solubility difference between the exposed area 50 and the unexposed area 52. If the heating operation is performed at a temperature or time less than the disclosed range, the crosslinking may be insufficient and the photoresist structure LWR may be reduced. If the temperature or time of the heating operation is greater than these ranges, too much crosslinking may occur and the LWR of the photoresist structure may be reduced. If there is too little crosslinking, a portion of the exposed area that should not be removed during the development operation may be removed during the development operation, and the resulting pattern does not have the desired clarity. If there is too much crosslinking in portions of the unexposed areas that should be removed during the development operation, they may not be removed and the resulting pattern will not have the desired clarity.

[0064] The selectively exposed photoresist structure is then developed in operation S150. In some embodiments, the multilayer photoresist structure 15 is developed by applying a solvent-based developer 57 to the selectively exposed multilayer photoresist structure 15. Figure 4A As shown, liquid developer 57 is supplied from dispenser 62 to multilayer photoresist structure 15. In some embodiments, due to exposure to actinic radiation or post-exposure baking, exposed portion 50 of photoresist structure undergoes a cross-linking reaction, and unexposed portions of photoresist structure 52 are removed by developer 57, thereby forming a pattern of openings 55 in photoresist structure 15 to expose substrate 10, as shown in FIG. Figure 5 shown.

[0065] In some embodiments, the photoresist developer 57 comprises a solvent and an acid or a base. In some embodiments, the concentration of the solvent is about 60 wt % to about 99 wt % based on the total weight of the photoresist developer. The concentration of the acid or base is about 0.001 wt % to about 20 wt % based on the total weight of the photoresist developer. In certain embodiments, the concentration of the acid or base in the developer is about 0.01 wt % to about 15 wt % based on the total weight of the photoresist developer.

[0066] In some embodiments, the developer 57 is applied to the multilayer photoresist structure 15 using a spin coating process. In the spin coating process, the developer 57 is applied to the multilayer photoresist structure 15 from above the multilayer photoresist structure 15 while the substrate coated with the photoresist is being rotated, such as Figure 4A As shown. In some embodiments, the developer 57 is supplied at a rate between about 5 ml / min and about 800 ml / min while the photoresist-coated substrate 10 is rotated at a speed between about 100 rpm and about 2000 rpm. In some embodiments, the developer is at a temperature between about 10° C. and about 80° C. In some embodiments, the development operation lasts from about 30 seconds to about 10 minutes.

[0067] In some embodiments, the developer 57 is an organic solvent. The organic solvent can be any suitable solvent. In some embodiments, the solvent is selected from one or more of the following: propylene glycol methyl ether acetate (PGMEA), propylene glycol monomethyl ether (PGME), 1-ethoxy-2-propanol (PGEE), γ-butyrolactone (GBL), cyclohexanone (CHN), ethyl lactate (EL), methanol, ethanol, propanol, n-butanol, 4-methyl-2-pentanol, acetone, methyl ethyl ketone, dimethylformamide (DMF), isopropyl alcohol (IPA), tetrahydrofuran (THF), methyl isobutyl carbinol (MIBC), n-butyl acetate (nBA), 2-heptanone (MAK), tetrahydrofuran (THF), and dioxane.

[0068] Although a spin coating operation is a suitable method for developing the multilayer photoresist structure 15 after exposure, it is intended to be illustrative and not intended to limit the embodiments. Instead, any suitable developing operation may alternatively be used, including an immersion process, a puddle process, and a spray coating method. All such developing operations are included within the scope of the embodiments.

[0069] In some embodiments, a dry developer 105 is applied to the selectively exposed multilayer photoresist structure 15, such as Figure 4B As shown. In some embodiments, dry developer 105 is plasma or chemical vapor, and dry development operation S150 is plasma etching or chemical etching operation. Dry development uses the difference related to composition, crosslinking degree and film density to selectively remove the resist of the desired part. In some embodiments, the dry development process uses a mild plasma (high pressure, low power) or thermal process in a heated vacuum chamber while making dry development chemicals such as BCl3, BF3 or other Lewis acids flow in a vapor state. In some embodiments, BCl3 removes unexposed material, leaving the pattern of the exposed film, which is transferred to the layer below by a plasma-based etching process.

[0070] In some embodiments, dry development includes a plasma process, including transformer coupled plasma (TCP), inductively coupled plasma (ICP), or capacitively coupled plasma (CCP). In some embodiments, the plasma process is performed at a pressure of about 5 mTorr to about 20 mTorr, a power level of about 250 W to about 1000 W, a temperature of about 0° C. to about 300° C., and at a flow rate of about 100 to about 1000 sccm for about 1 to about 3000 seconds.

[0071] In some embodiments, the pattern of openings 55 in the multilayer photoresist structure 15 extends into the layer to be patterned or the substrate 10 to produce a pattern of openings 55' in the substrate 10, thereby transferring the pattern in the photoresist layer 15 to the substrate 10, such as Figure 6 As shown. Using one or more suitable etchants, the pattern is extended into the substrate by etching. In some embodiments, the exposed multi-layer photoresist structure 15 is at least partially removed during the etching operation. In other embodiments, after etching the substrate 10, the exposed photoresist layer 15 is removed by using a suitable photoresist stripping solvent or by a photoresist ashing operation.

[0072] In some embodiments, substrate 10 includes a single crystal semiconductor layer on at least a portion of its surface. Substrate 10 may include a single crystal semiconductor material, such as but not limited to Si, Ge, SiGe, GaAs, InSb, GaP, GaSb, InAlAs, InGaAs, GaSbP, GaAsSb, and InP. In some embodiments, substrate 10 is a silicon layer of a SOI (silicon on insulator) substrate. In certain embodiments, substrate 10 is made of crystalline Si.

[0073] The substrate 10 may include one or more buffer layers (not shown) in its surface region. The buffer layer may be used to gradually change the lattice constant from the lattice constant of the substrate to the lattice constant of the subsequently formed source / drain region. The buffer layer may be formed of an epitaxially grown single crystalline semiconductor material, such as but not limited to Si, Ge, GeSn, SiGe, GaAs, InSb, GaP, GaSb, InAlAs, InGaAs, GaSbP, GaAsSb, GaN, GaP, and InP. In one embodiment, a silicon germanium (SiGe) buffer layer is epitaxially grown on the silicon substrate 10. The germanium concentration of the SiGe buffer layer may increase from 30 atomic % of the bottommost buffer layer to 70 atomic % of the topmost buffer layer.

[0074] In some embodiments, the substrate 10 includes one or more layers of at least one metal, metal alloy, and metal having the formula MA aA metal nitride / sulfide / oxide / silicide of 200 μm / s, wherein M is a metal and A is N, S, Se, O, Si, and a is from about 0.4 to about 2.5. In some embodiments, substrate 10 comprises titanium, aluminum, cobalt, ruthenium, titanium nitride, tungsten nitride, tantalum nitride, and combinations thereof.

[0075] In some embodiments, substrate 10 includes a dielectric material having at least the formula MA b Silicon or metal oxide or nitride, wherein M is metal or Si, A is N or O, and b ranges from about 0.4 to about 2.5. In some embodiments, the substrate 10 comprises silicon dioxide, silicon nitride, aluminum oxide, hafnium oxide, lanthanum oxide, and combinations thereof.

[0076] A photoresist layer is a photosensitive layer patterned by exposure to actinic radiation. Typically, the chemical properties of the photoresist area struck by the incident radiation change in a manner that depends on the type of photoresist used. A photoresist layer is a positive resist or a negative resist. A positive resist refers to a photoresist material that becomes soluble in a developer when exposed to radiation (such as ultraviolet light), while the unexposed (or less exposed) areas of the photoresist are insoluble in the developer. On the other hand, a negative resist refers to a photoresist material that becomes insoluble in a developer when exposed to radiation, while the unexposed (or less exposed) areas of the photoresist are soluble in the developer. The areas of a negative resist that become insoluble when exposed to radiation may become insoluble due to crosslinking reactions caused by exposure to radiation.

[0077] In some embodiments, the photoresist layer is made of a photoresist composition comprising a first compound or a first precursor and a second compound or a second precursor combined in a vapor state. In some embodiments, the first precursor or the first compound is a compound having a formula M a R b X c Organic metals, such as Fig. 7AAs shown, wherein M is one or more metals selected from Sn, Bi, Sb, In and Te; R is a substituted or unsubstituted alkyl, alkenyl or carboxylate group. In some embodiments, R is a C3-C6 alkyl, alkenyl or carboxylate. In some embodiments, R is one or more selected from propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, pentyl, isopentyl, sec-pentyl, tert-pentyl, hexyl, isohexyl, sec-hexyl and tert-hexyl. In some embodiments, X is a ligand, ion or other fragment that reacts with a second compound or a second precursor; 1≤a≤2, b≥1, c≥1, and b+c≤5. In some embodiments, the alkyl, alkenyl or carboxylate group is substituted with one or more fluorine groups. In some embodiments, the organometallic precursor is a dimer, such as Fig. 7A As shown, each monomer unit is connected by an amine group. Each monomer has a formula M as defined above. a R b X c .

[0078] In some embodiments, R is fluorinated, for example having the formula C n F x H ((2n+1)-x) , wherein 3≤n≤6. In some embodiments, R has at least one β-hydrogen or β-fluorine. In some embodiments, R is one or more selected from isopropyl, n-propyl, tert-butyl, isobutyl, n-butyl, sec-butyl, n-pentyl, isopentyl, tert-pentyl and sec-pentyl.

[0079] In some embodiments, X is any fragment that is easily replaced by a second compound or a second precursor to produce an M-OH fragment, such as a fragment selected from the group consisting of: amine (including dialkylamino and monoalkylamino); alkoxy; carboxylate, halogen and sulfonate. In some embodiments, the sulfonate group is substituted with one or more amine groups. In some embodiments, the halide is one or more selected from the group consisting of F, Cl, Br and I. In some embodiments, the sulfonate group comprises a substituted or unsubstituted C1-C3 group.

[0080] In some embodiments, the first organometallic compound or the first organometallic precursor includes a metal core M + , whose ligand L is connected to the metal core M + ,like Figure 7B In some embodiments, the metal core M +In some embodiments, ligand L includes C3-C12 aliphatic or aromatic groups.Aliphatic or aromatic groups can be unbranched or branched with cyclic or non-cyclic saturated side groups (including alkyl, alkenyl and phenyl) containing 1 to 9 carbons. Branched groups can be further replaced by oxygen or halogen. In some embodiments, C3-C12 aliphatic or aromatic groups include heterocyclic groups. In some embodiments, C3-C12 aliphatic or aromatic groups are connected to metal by ether or ester bonds. In some embodiments, C3-C12 aliphatic or aromatic groups include nitrite and sulfonate substituents.

[0081] Figure 7B The reaction that a metal precursor undergoes in some embodiments due to exposure to actinic radiation is shown. Due to exposure to actinic radiation, the ligand group L is removed from the metal core M of the metal precursor. + separate, and two or more metal precursor cores are bonded to each other.

[0082] In some embodiments, the organometallic precursor or organometallic compound includes secondary hexyltri(dimethylamino)tin, tert-hexyltri(dimethylamino)tin, isohexyltri(dimethylamino)tin, n-hexyltri(dimethylamino)tin, secondary amyltri(dimethylamino)tin, tert-amyltri(dimethylamino)tin, isopentyltri(dimethylamino)tin, n-amyltri(dimethylamino)tin, secondary butyltri(dimethylamino)tin, tert-butyltri(dimethylamino)tin, isobutyltri(dimethylamino)tin, n-butyltri(dimethylamino)tin, secondary butyltri(dimethylamino)tin, isopropyltri(dimethylamino)tin In some embodiments, the organometallic precursor or organometallic compound is fluorinated. In some embodiments, the boiling point of the organometallic precursor or compound is less than about 200°C.

[0083] Figure 7C Examples of organometallic precursors according to embodiments of the present disclosure are shown. Figure 7C In the above, Bz refers to a phenyl group.

[0084] In some embodiments, the first compound or the first precursor comprises one or more unsaturated bonds that can coordinate with functional groups (eg, hydroxyl groups) on the surface of the substrate or the intermediate underlayer to improve adhesion of the photoresist layer to the substrate or the underlayer.

[0085] In some embodiments, the second precursor or second compound is one or more selected from water, amines, boranes, and phosphines. In some embodiments, the amine has the formula N p H n X m , wherein 0≤n≤3, 0≤m≤3, n+m=3 when p is 1, and n+m=4 when p is 2, and each X is independently a halogen selected from F, Cl, Br and I. In some embodiments, the borane has the formula B p H n X m , wherein 0≤n≤3, 0≤m≤3, n+m=3 when p is 1, and n+m=4 when p is 2, and each X is independently a halogen selected from F, Cl, Br and I. In some embodiments, the phosphine has the formula P p H n X m , wherein 0≤n≤3, 0≤m≤3, n+m=3 when p is 1, or n+m=4 when p is 2, and each X is independently a halogen selected from F, Cl, Br and I.

[0086] In some embodiments, the second precursor or compound is water, ammonia or hydrazine. The reaction product of water, ammonia or hydrazine with the organometallic precursor or compound can form hydrogen bonds, which increase the boiling point of the reaction product and prevent the emission of the metal photoresist material, thereby preventing metal contamination. In some embodiments, hydrogen bonds can also help prevent moisture from affecting the quality of the photoresist layer.

[0087] In some embodiments, the operation S110 of depositing the photoresist composition is performed by a vapor deposition operation. In some embodiments, the vapor deposition operation includes atomic layer deposition (ALD) or chemical vapor deposition (CVD). In some embodiments, ALD includes plasma enhanced atomic layer deposition (PE-ALD), and CVD includes plasma enhanced chemical vapor deposition (PE-CVD), metal organic chemical vapor deposition (MO-CVD); atmospheric pressure chemical vapor deposition (AP-CVD) and low pressure chemical vapor deposition (LP-CVD).

[0088] According to some embodiments of the present disclosure, the resist layer deposition apparatus 200 is Figure 8. In some embodiments, the deposition apparatus 200 is an ALD or CVD apparatus. The deposition apparatus 200 includes a vacuum chamber 205. A substrate support table 210 in the vacuum chamber 205 supports a substrate 10 such as a silicon wafer. In some embodiments, the substrate support table 210 includes a heater. In some embodiments, a first precursor or compound gas supplier 220 and a carrier gas / purge gas supplier 225 are connected to an inlet 230 in the chamber via a gas line 235, and a second precursor or compound gas supplier 240 and a carrier gas / purge gas supplier 225 are connected to another inlet 230' in the chamber 230' via another gas line 235'. The chamber is evacuated, and excess reactants and reaction byproducts are removed via an outlet 250 and an exhaust line 255 by a vacuum pump 245. In some embodiments, the flow rates or pulses of precursor gases and carrier / purge gases, the exhaust of excess reactants and reaction byproducts, the pressure within the vacuum chamber 205, and the temperature of the vacuum chamber 205 or the wafer support table 210 are controlled by a controller 260 configured to control each of these parameters.

[0089] Depositing the photoresist layer includes combining a first compound or a first precursor with a second compound or a second precursor in a vapor state to form a photoresist composition. In some embodiments, the first compound or a first precursor and the second compound or a second precursor of the photoresist composition are introduced into the deposition chamber 205 (CVD chamber) via inlets 230, 230' at about the same time. In some embodiments, the first compound or a first precursor and the second compound or a second precursor are introduced into the deposition chamber 205 (ALD chamber) via inlets 230, 230' in an alternating manner, i.e., the first compound or a precursor, then the second compound or a precursor, and then the first compound or a precursor is introduced alternately and repeatedly, and then the second compound or a precursor is introduced.

[0090] In some embodiments, during the deposition operation, the temperature of the deposition chamber is in the range of about 30°C to about 400°C, and in other embodiments, between about 50°C to about 250°C. In some embodiments, during the deposition operation, the pressure in the deposition chamber is in the range of about 5mTorr to about 100Torr, and in other embodiments, in the range of about 100mTorr to about 10Torr. In some embodiments, the plasma power is less than about 1000W. In some embodiments, the plasma power is in the range of about 100W to about 900W. In some embodiments, the flow rate of the first compound or precursor and the second compound or precursor is in the range of about 100sccm to about 1000sccm. In some embodiments, the ratio of the flow rate of the organometallic compound precursor to the second compound or precursor is about 1:1 to about 1:5. In some embodiments, at operating parameters outside the above ranges, unsatisfactory photoresist layers result. In some embodiments, the formation of the photoresist layer occurs in a single chamber (single pot layer formation).

[0091] In a CVD process according to some embodiments of the present disclosure, two or more gas streams of an organic metal precursor and a second precursor are introduced into a deposition chamber 205 of a CVD apparatus in separate inlet paths 230, 235 and 230', 235', where they mix and react in the gas phase to form a reaction product. In some embodiments, separate injection inlets 230, 230' or dual booster nozzles are used to introduce each stream. The deposition apparatus is configured to mix the streams of the organic metal precursor and the second precursor in the chamber, thereby reacting the organic metal precursor and the second precursor to form a reaction product. Without limiting the mechanism, function or utility of the present disclosure, it is believed that the molecular weight of the product from the gas phase reaction becomes larger and is then condensed or otherwise deposited on the substrate 10.

[0092] In some embodiments, an ALD process is used to deposit a photoresist layer. During ALD, a layer is grown on the substrate 10 by exposing the surface of the substrate to alternating gaseous compounds (or precursors). In contrast to CVD, the precursors are introduced as a series of sequential, non-overlapping pulses. In each of these pulses, the precursor molecules react with the surface in a self-limiting manner, so that the reaction terminates once all reactive sites on the surface are consumed. Therefore, after a single exposure to all precursors (the so-called ALD cycle), the maximum amount of material deposited on the surface depends on the nature of the interaction of the precursors with the surface.

[0093] In one embodiment of the ALD process, in the first half of the reaction, the organometallic precursor is pulsed to deliver the metal-containing precursor to the surface of the substrate 10. In some embodiments, the organometallic precursor reacts with a suitable species below (e.g., OH or NH functional groups on the substrate surface) to form a new self-saturated surface. In some embodiments, excess unused reactants and reaction byproducts are removed by vacuuming downward using a vacuum pump 245 and / or by flowing an inert purge gas. Then, in some embodiments, a second precursor such as ammonia (NH3) is pulsed into the deposition chamber. NH3 reacts with the organometallic precursor on the substrate to obtain a reaction product photoresist on the substrate surface. The second precursor also forms a self-saturated bond with the reactive species below to provide another self-limiting and saturated second half reaction. In some embodiments, a second purge is performed to remove unused reactants and reaction byproducts. The pulses of the first and second precursors are alternately performed with the purge operation in the middle until the desired photoresist layer thickness is obtained.

[0094] In some embodiments, each photoresist layer is formed to a thickness of about 5nm to about 50nm, and in other embodiments, is formed to a thickness of about 10nm to about 30nm. Those of ordinary skill in the art will recognize that other ranges of thickness within the above-defined range are expected and within the present disclosure. The thickness can be evaluated based on the optical properties of the photoresist layer using a non-contact method of X-ray reflectivity and / or ellipsometry. In some embodiments, the thickness of each photoresist layer is relatively uniform to facilitate processing. In some embodiments, the thickness variation of the deposited photoresist layer differs from the average thickness by no more than ±25%, and in other embodiments, the thickness of each photoresist layer differs from the average photoresist layer thickness by no more than ±10%. In some embodiments, such as high uniformity deposition on a larger substrate, the uniformity of the photoresist layer can be evaluated with a 1 cm edge exclusion, that is, the layer uniformity of the coating portion within 1 cm of the edge is not evaluated. Those of ordinary skill in the art will recognize that other ranges within the above-defined range are expected and within the present disclosure.

[0095] In some embodiments, the first compound or precursor and the second compound or precursor are delivered with a carrier gas into the deposition chamber 205. The carrier gas, purge gas, deposition gas, or other process gas may include nitrogen, hydrogen, argon, neon, helium, or combinations thereof.

[0096] In some embodiments, the organometallic compound comprises tin (Sn), antimony (Sb), bismuth (Bi), indium (In) and / or tellurium (Te) as metal components, but the present disclosure is not limited to these metals. In other embodiments, other suitable metals include titanium (Ti), zirconium (Zr), hafnium (Hf), vanadium (V), cobalt (Co), molybdenum (Mo), tungsten (W), aluminum (Al), gallium (Ga), silicon (Si), germanium (Ge), phosphorus (P), arsenic (As), yttrium (Y), lanthanum (La), cerium (Ce), lutetium (Lu) or a combination thereof. These other metals can be used as a substitute or supplement for Sn, Sb, Bi, In and / or Te.

[0097] The specific metal used can significantly affect the absorption of radiation. Therefore, the metal composition can be selected based on the desired radiation and absorption cross section. Tin, antimony, bismuth, tellurium and indium can strongly absorb extreme ultraviolet light at 13.5nm. Hafnium provides good electron beam absorption and extreme ultraviolet radiation absorption. Metal compositions containing titanium, vanadium, molybdenum or tungsten have strong absorption at longer wavelengths to provide, for example, sensitivity to ultraviolet light at a wavelength of 248nm.

[0098] Fig. 9 The reactions that components of a photoresist composition according to one embodiment of the present disclosure undergo as a result of exposure to actinic radiation and heat are shown. Fig. 9 2 shows an exemplary chemical structure of a photoresist structure (PR) at various stages of a photoresist structure patterning method according to an embodiment of the present disclosure. Fig. 9 As shown, the photoresist composition includes an organic metal compound (e.g., SnX2R2), and a second compound, such as ammonia (NH3). When the organic metal compound and ammonia are combined, the organic metal compound reacts with some ammonia in the gas phase to form a reaction product having an amine group connected to the metal (Sn) of the organic metal compound. The amine group in the deposited photoresist layer has a hydrogen bond, which can substantially increase the boiling point of the deposited photoresist layer and prevent the degassing of the metal-containing photoresist material, thereby preventing the metal in the metal-containing photoresist from contaminating the deposition chamber and semiconductor device processing equipment. In the metal-containing photoresist. In addition, the hydrogen bond of the amine group can control the effect of moisture on the quality of the photoresist layer.

[0099] When subsequently exposed to EUV radiation using a mask, the organometallic compound absorbs the EUV radiation and one or more organic R groups are cleaved from the organometallic compound, thereby forming an amide metal compound in the radiation exposed areas. Then, in some embodiments, when a post-exposure bake (PEB) is performed, the amide metal compound is cross-linked through the amine groups, such as Fig. 9In some embodiments, the metal amide compound is partially crosslinked due to exposure to extreme ultraviolet radiation. The selectively exposed photoresist is then developed, and the crosslinked radiation-exposed pattern is retained on the substrate while the unexposed radiation areas are removed during development.

[0100] As described above, uneven exposure of the photoresist (especially at deeper portions of the photoresist layer) may result in uneven crosslinking of the photoresist, which results in poor line width roughness (LWR), profile of the T-top resist, and / or formation of photoresist scum in the developed area of ​​the photoresist pattern. In order to prevent problems caused by uneven photoresist exposure, embodiments of the present disclosure use a multilayer or gradient photoresist layer structure as the photoresist structure 15. By adjusting the amount of water present during the deposition operation, changing the thickness of the metal-containing resist, changing the flow rate of the metal resist precursor, or changing the heating conditions (time and temperature) of the photoresist structure, a multilayer photoresist structure or a gradient photoresist layer 15 with different crosslinking degrees can be formed to overcome the uneven exposure problem.

[0101] like Fig. 10A , 12A As shown in Figures 13A, multiple layers are formed by changing the photoresist layer formation parameters (including the amount of water), changing the metal-containing resist thickness, changing the metal resist precursor, and changing the photoresist baking conditions. Depending on the layer formation conditions (including the amount of water), the amount of metal resist precursor, and the baking / heating conditions of the photoresist before exposure to actinic radiation, some crosslinking occurs in the photoresist layer. Exposure to actinic radiation and post-exposure baking substantially increase the amount of crosslinking in the exposed areas of the photoresist layer, and in some embodiments is responsible for most of the crosslinking.

[0102] For example, in Fig. 10A In the embodiment, an upper layer 15c having a first crosslinking density is formed on an intermediate layer 15b having a second crosslinking density (greater than the first crosslinking density of the upper layer 15c), which in turn is formed on an underlying layer 15a having a third crosslinking density (greater than the second crosslinking density of the intermediate layer 15b). The upper layer of the photoresist absorbs more radiation than the lower layer. Fig. 10B As shown, when EUV light 45 passes through a multi-layer photoresist structure having an upper layer 15 c with a low cross-linking density and a large energy absorption, a middle layer 15 b with a medium cross-linking density and a medium energy absorption, and a lower layer 15 a with a high cross-linking density and a lower energy absorption, in some embodiments, the total thickness of the exposed portion of the photoresist structure will have the same degree of cross-linking, thereby providing an improved LWR for the photoresist pattern 55 without a T-top shape, as shown in FIG. Fig. 10C shown.

[0103] In some embodiments, Fig. 10A and 10B In the photoresist structure shown, the upper photoresist layer 15c is thinner than the middle photoresist layer 15b, and the middle photoresist layer 15b is thinner than the lower photoresist layer 15a. Fig. 10A and 10B In the photoresist structure shown, the metal resist precursor concentration of the upper photoresist layer 15c is lower than that of the middle photoresist layer 15b, and the metal resist precursor concentration of the middle photoresist layer 15b is lower than that of the lower photoresist layer 15a. In other embodiments, the upper photoresist layer 15c is pre-exposed and baked at a lower temperature or a shorter time than the middle photoresist layer 15b, and the middle photoresist layer 15b is pre-exposed and baked at a lower temperature or a shorter time than the lower photoresist layer 15a. In other embodiments, the amount (concentration) of the second compound or precursor in the deposition chamber during the deposition operation of the upper photoresist layer 15c is less than the amount (concentration) of the second compound or precursor during the deposition operation of the middle photoresist layer 15b, and the amount of the second compound or precursor in the deposition chamber during the deposition operation of the middle photoresist layer 15b is less than the amount of the second compound or precursor during the deposition operation of the lower photoresist layer 15a. In some embodiments, the amount of the second compound or precursor in the deposition chamber is controlled by controlling the pressure of the second compound or precursor introduced into the deposition chamber, controlling the flow rate of the second compound or precursor introduced into the deposition chamber, or controlling the time that the second precursor or compound flows into the deposition chamber. In some embodiments, the second precursor or compound is water vapor.

[0104] In some embodiments, the degree of crosslinking or crosslinking density is determined based on the processing parameters. For example, a higher concentration or flow rate of the second compound or precursor, a longer amount of time that the second precursor or compound flows into the deposition chamber, a higher heating temperature, or a longer duration of heating the deposited resist layer provides a higher degree of crosslinking or a higher crosslinking density of the photoresist layer. Conversely, a lower concentration or flow rate of the second compound or precursor, a shorter amount of time that the second precursor or compound flows into the deposition chamber, a lower heating temperature, or a shorter duration of heating the deposited resist layer provides a lower degree of crosslinking or a lower crosslinking density of the photoresist layer.

[0105] In some embodiments, the thickness of each of the photoresist layers 15a, 15b, 15c is in the range of about 5 nm to about 50 nm. At a thickness of less than about 5 nm, the photoresist layer does not have sufficient thickness to fully function as desired and protect the underlying substrate from subsequent processing including etching. At a thickness greater than about 50 nm, no additional performance improvement is obtained and the semiconductor manufacturing process efficiency is reduced.

[0106] In various embodiments, different methods are used to obtain the arrangement of the photoresist layers in the multi-layer photoresist structure, such as Fig.11A and 11B shown. Fig.11A and 11B A table showing parameters of a photoresist layer of a multi-layer photoresist structure according to an embodiment of the present disclosure is shown.

[0107] In one embodiment, if Fig.11A As shown, a multilayer photoresist 15 is formed by changing the concentration of an organic metal precursor in a deposition chamber during formation of a photoresist layer. The multilayer photoresist 15 has a lower layer 15a with a high crosslinking density, an intermediate layer 15b with a medium crosslinking density, and an upper layer 15c with a low crosslinking density, corresponding to Fig. 10A A multilayer photoresist structure 15. The thickness of each photoresist layer is approximately the same, and the water concentration in the deposition chamber is approximately the same. By changing the concentration of the organic metal precursor in the deposition chamber during the formation of the photoresist layer, the upper layer 15c is formed under a lower concentration of the organic metal precursor, the middle layer 15b is formed under a higher organic metal precursor concentration of the upper layer 15c, and the lower layer 15a is formed under a higher organic metal precursor concentration than the middle layer 15b, thereby obtaining the desired crosslinking density of each layer. In some embodiments, the concentration of the organic metal precursor of each layer and the degree of crosslinking or crosslinking density are determined based on the processing parameters. For example, a higher concentration or flow rate of the first compound or precursor or a longer time for the first precursor or compound to flow into the deposition chamber provides a higher concentration of the organic metal precursor and a higher degree of crosslinking or a higher crosslinking density of the photoresist layer. Conversely, a lower concentration or flow rate of the first compound or precursor or a shorter time for the second precursor or the second compound to flow into the deposition chamber provides a lower concentration of the organic metal precursor and a lower degree of crosslinking or a lower crosslinking density of the photoresist layer. The greater the concentration of the organometallic precursor in the deposition chamber during the formation of the photoresist layer, the greater the amount of the organometallic precursor that may undergo cross-linking during the formation of the photoresist layer.

[0108] In another embodiment, Fig. 11BAs shown, a multilayer photoresist structure 15 is formed by changing the water concentration in the photoresist deposition chamber. The multilayer photoresist structure 15 has a high cross-linking density lower layer 15a, a middle cross-linking density middle layer 15b and a low cross-linking density upper layer 15c, corresponding to Fig. 10B A multilayer photoresist structure 15 is provided. The thickness of each photoresist layer is approximately the same, and the metal concentration in each photoresist layer is approximately the same. The desired crosslink density of each layer is obtained by changing the water concentration in the photoresist deposition chamber so that the upper layer 15c is formed at a lower water concentration, the middle layer 15b is formed at a greater water concentration than the formation of the upper layer 15c, and the lower layer 15a is formed at a greater concentration than the formation of the middle layer 15b.

[0109] In some embodiments, the amount of water in the deposition chamber is controlled to maintain a water vapor concentration of less than about 10 weight percent of the total weight of water vapor and other reactant precursors or compounds used to form the photoresist layer in the deposition chamber. In some embodiments, the water vapor concentration is about 0.1 weight percent to about 10 weight percent based on the total amount of water and reactant precursors or compounds. In some embodiments, the molar ratio of the metal-containing precursor or compound to water is about 1:0.1 to about 1:2. The higher the water vapor concentration, the higher the degree of crosslinking or crosslinking density of the photoresist layer. Conversely, a lower water vapor concentration provides a lower degree of crosslinking or crosslinking density of the photoresist layer. If the water vapor concentration is above about 10%, the photoresist structure LWR is reduced. If the water vapor concentration is less than about 0.1%, the crosslinking in the photoresist structure may be insufficient. If there is too little crosslinking, a portion of the exposed area that should not be removed during the development operation may be removed during the development operation, and the resulting pattern does not have the desired clarity. If there is too much crosslinking in the portion of the unexposed area that should be removed during the development operation, it may not be removed, and the resulting pattern does not have the desired clarity.

[0110] In some embodiments, the degree of crosslinking or crosslinking density is determined based on the processing parameters. For example, a higher concentration or flow rate of water vapor or a longer time for the water vapor to flow into the deposition chamber provides a higher degree of crosslinking or a higher crosslinking density of the photoresist layer. Conversely, a lower concentration or flow rate of water vapor or a shorter time for the water vapor to flow into the deposition chamber provides a lower degree of crosslinking or a lower crosslinking density of the photoresist layer.

[0111] In another embodiment, Figures 12A-12CAs shown, by changing the formation parameters of the photoresist layer (including the concentration of H2O), changing the thickness of the metal-containing resist, changing the metal resist precursor, and changing the photoresist baking conditions, the upper photoresist layer 15c has the highest cross-linking density and the lower photoresist layer 15a has the lowest cross-linking density. In some embodiments, the higher cross-linking density of the upper photoresist layer 15c prevents degassing problems. The lower photoresist layer 15a with a low cross-linking density on the bottom of the multi-layer photoresist structure 15 is more easily dissolved / removed by the developer, thereby reducing scum defects.

[0112] For example, Fig. 12A As shown, an upper layer 15c having a first crosslinking density is formed on an intermediate layer 15b having a second crosslinking density (less than the first crosslinking density of the upper layer 15c), which in turn is formed on a lower layer 15a having a third crosslinking density (less than the second crosslinking density of the intermediate layer 15b). The upper layer of the photoresist absorbs more radiation than the lower layer. Fig. 12B As shown, in some embodiments, when EUV light 45 passes through an upper layer 15c having a high crosslink density and a large energy absorption, an intermediate layer 15b having a medium crosslink density and a medium energy absorption, and a lower layer 15a having a low crosslink density and a low energy absorption, the total thickness of the exposed portion of the photoresist structure will have a crosslink gradient from a high crosslink degree of the highest photoresist layer to a low crosslink degree of the lowest photoresist layer. This structure provides a photoresist pattern 55 with a higher density upper layer and a lower density lower layer, wherein the higher density upper layer prevents degassing of the photoresist and subsequent contamination in the deposition chamber, while the lower density lower layer can improve the development of the lower photoresist layer and prevent the formation of photoresist scum in the lower photoresist layer, as shown in FIG. Fig. 12C In some embodiments, the patterned photoresist features have a wider width at the upper portion of the photoresist pattern 50 than at the lower portion of the photoresist pattern 50 due to the higher crosslink density in the upper portion and the lower crosslink density in the lower portion, as shown in FIG. Fig. 12C As shown. In some embodiments, the degree of crosslinking in each photoresist layer is controlled so as to obtain a desired resist profile. If the difference in crosslinking between the upper photoresist layer and the lower photoresist layer is too large, the resulting taper of the patterned resist profile may be too large. In some embodiments, an intermediate layer between the upper resist layer and the lower resist layer improves the adhesion between the upper resist layer and the lower resist layer.

[0113] In some embodiments, Fig. 12A and 12BIn the photoresist structure shown in FIG. 1 , the upper photoresist layer 15c is thicker than the middle photoresist layer 15b, and the middle photoresist layer 15b is thicker than the lower photoresist layer 15a. Fig. 12A and 12B In the photoresist structure shown, the upper photoresist layer 15c has a higher metal resist precursor concentration than the middle photoresist layer 15b, and the middle photoresist layer 15b has a higher metal resist precursor concentration than the lower photoresist layer 15a. In other embodiments, the upper photoresist layer 15c is pre-exposed and baked at a higher temperature or longer time than the middle photoresist layer 15b, and the middle photoresist layer 15b is pre-exposed and baked at a higher temperature or longer time than the lower photoresist layer 15a. In other embodiments, during the deposition operation of the upper photoresist layer 15c, the amount of the second compound or precursor in the deposition chamber is greater than the amount of the second compound or precursor in the deposition chamber during the deposition operation of the middle photoresist layer 15b, and the amount of the second compound or precursor in the deposition chamber during the deposition operation of the middle photoresist layer 15b is greater than the amount of the second compound or precursor in the deposition chamber during the deposition operation of the lower photoresist layer 15a.

[0114] In another embodiment, Figures 13A-13C As shown, the multilayer photoresist structure 15 includes multiple photoresist layers 15a, 15b, 15c, 15d, 15e with different cross-linking densities and thicknesses to eliminate scum and provide improved LWR. In some embodiments, as disclosed herein, adjusting the photoresist layer formation parameters to solve the T-top formation may not solve the scum defects and photoresist outgassing. On the other hand, in some embodiments, as disclosed herein, adjusting the photoresist layer formation parameters to solve the scum defects and photoresist outgassing problems may not solve the T-top formation. Therefore, in some embodiments, multiple photoresist layers with different cross-linking densities are formed and arranged to eliminate scum and outgassing while providing improved LWR. For example, in some embodiments, a bottom layer 15a having a first thickness and a first cross-linking density is formed above the substrate 10. Then, three intermediate layers 15b, 15c, 15d are formed above the bottom layer 15a. The three intermediate layers 15b, 15c, 15d are similar to those in Figures 10A-10CAn upper intermediate layer 15d having a second crosslink density and a second thickness is formed over a second intermediate layer 15c, the second intermediate layer 15c having a third crosslink density greater than the second crosslink density of the upper intermediate layer 15d, the second intermediate layer 15c in turn being formed over a lower intermediate layer 15b having a fourth crosslink density greater than the third crosslink density of the second intermediate layer 15c and having a fourth thickness. A top layer 15e having a fifth crosslink density and a fifth thickness is formed over the upper intermediate layer 15d.

[0115] The fifth crosslink density of the top layer 15e is greater than the first crosslink density of the bottom layer 15a, the second crosslink density of the upper middle layer 15d, and the third crosslink density of the second middle layer 15c. The first crosslink density of the bottom layer 15a is less than the third crosslink density of the second middle layer 15c, the fourth crosslink density of the lower middle layer 15b, and the fifth crosslink density of the top layer 15e. In some embodiments, the first thickness of the bottom layer 15a is less than the second thickness of the upper middle layer 15d, the third thickness of the second middle layer 15c, and the fourth thickness of the lower middle layer 15b. In some embodiments, the fifth thickness of the top layer 15e is less than the second thickness of the upper middle layer 15d, the third thickness of the second middle layer 15c, and the fourth thickness of the lower middle layer 15b.

[0116] In some embodiments, the first thickness of the bottom layer 15a and the fifth thickness of the top layer 15e are independently in the range of about 0.5 nm to about 45 nm. In some embodiments, the second thickness of the upper intermediate layer 15d, the third thickness of the second intermediate layer 15c, and the fourth thickness of the lower intermediate layer 15b are independently in the range of about 5 nm to about 50 nm.

[0117] In some embodiments of the present disclosure, rather than forming separate discrete photoresist layers, the photoresist structure 15 is formed as one continuous layer, wherein the photoresist deposition parameters are varied during deposition of the photoresist layer to produce a photoresist layer having a gradient crosslink density across the thickness of the photoresist layer. In some embodiments, the crosslink density of the photoresist varies continuously from a maximum crosslink density at the photoresist layer 15 / substrate 10 interface to a minimum crosslink density at the upper surface of the photoresist layer 15. In other embodiments, the crosslink density of the photoresist varies continuously from a minimum crosslink density at the photoresist layer 15 / substrate 10 interface to a maximum crosslink density at the upper surface of the photoresist layer 15.

[0118] like Fig. 13BAs shown, the multilayer photoresist structure 15 is pattern-wise exposed to EUV light 45. The high crosslink density of the top photoresist layer 15e reduces or prevents outgassing of the photoresist multilayer structure 15 and subsequent contamination of semiconductor device processing chambers and tools. Fig. 13C As shown, the low cross-link density of the bottom photoresist layer 15a reduces or prevents scum defects. Fig. 13C As shown, the three intermediate layers 15b, 15c, 15d are arranged in sequence starting from the lower intermediate layer upwards, with decreasing crosslinking density to obtain approximately the same degree of crosslinking after exposure to actinic radiation, thereby obtaining the same Figures 10A-10C The embodiment is similar to the improved LWR.

[0119] In some embodiments, before forming the multilayer photoresist structure 15, the layer 60 to be patterned is disposed on the substrate, such as Fig.14 As shown. In some embodiments, the layer 60 to be patterned is a metallization layer or a dielectric layer disposed above the metallization layer, such as a passivation layer. In embodiments in which the layer 60 to be patterned is a metallization layer, the layer 60 to be patterned is formed of a conductive material using a metallization process and a metal deposition technique including chemical vapor deposition, atomic layer deposition, and physical vapor deposition (sputtering). Similarly, if the layer 60 to be patterned is a dielectric layer, the layer 60 to be patterned is formed by a dielectric layer formation technique including thermal oxidation, chemical vapor deposition, atomic layer deposition, and physical vapor deposition.

[0120] The multilayer photoresist structure 15 is then selectively exposed to actinic radiation 45 to form exposed regions 50 and unexposed regions 52 in the multilayer photoresist structure, such as Fig.15A and 15B As stated above, and herewith Figure 3A and 3B As explained herein, in some embodiments, the photoresist layers 15a, 15b are negative photoresists.

[0121] like Fig.16A As shown, the unexposed photoresist areas 52 are developed by dispensing developer 57 from a dispenser 62, or by a dry developing operation, such as Fig. 16B As shown, a photoresist pattern 55 is formed to develop the unexposed photoresist region 52, as shown in FIG. Fig.17 The development operation is similar to that described in the present invention. Figure 4A , 4B and 5.

[0122] Then, if Fig.18As shown, an etching operation is used to transfer the pattern 55 in the photoresist layer 15 to the layer 60 to be patterned, and the photoresist layer is removed, as shown in FIG. Figure 6 As explained, a pattern 55" is thereby formed in the layer 60 to be patterned.

[0123] Other embodiments include other operations before, during, or after the above operations. In some embodiments, the disclosed method includes forming a fin field effect transistor (FinFET) structure. In some embodiments, a plurality of active fins are formed on a semiconductor substrate. Such an embodiment further includes etching the substrate through the openings of the patterned hard mask to form trenches in the substrate; filling the trenches with a dielectric material; performing a chemical mechanical polishing (CMP) process to form shallow trench isolation (STI) features; epitaxially growing or recessing the STI features to form a fin-shaped active area. In some embodiments, one or more gate electrodes are formed on the substrate. Some embodiments include forming gate spacers, doped source / drain regions, contacts for gate / source / drain features, and the like. In other embodiments, the target pattern is formed as a metal line in a multilayer interconnect structure. For example, the metal line can be formed in an interlayer dielectric (ILD) layer of the substrate, which has been etched to form a plurality of trenches. The trenches may be filled with a conductive material, such as a metal; and a process such as chemical mechanical planarization (CMP) may be used to polish the conductive material to expose the patterned ILD layer, thereby forming metal lines in the ILD layer. The above are non-limiting examples of devices / structures that may be manufactured and / or improved using the methods described herein.

[0124] In some embodiments, active components such as diodes, field effect transistors (FETs), metal oxide semiconductor field effect transistors (MOSFETs), complementary metal oxide semiconductor (CMOS) transistors, bipolar transistors, high voltage transistors, high frequency transistors, FinFETs, other three-dimensional (3D) FETs, other memory cells, and combinations thereof are formed according to embodiments of the present disclosure.

[0125] By adjusting the amount of the second compound or precursor (e.g., water), changing the thickness of the metal-containing photoresist, the metal-containing photoresist precursor, and the time and temperature of the photoresist baking conditions, a merged multilayer photoresist structure with different crosslinking degrees is formed to overcome the uneven exposure problem. The photoresist layer structure and patterning method disclosed herein prevent T-shaped top resist pattern profiles, reduce scum defects, and prevent degassing and subsequent contamination of semiconductor manufacturing processing tools. The embodiments disclosed herein improve line width roughness and the difference between the exposed and unexposed portions of the photoresist. The embodiments disclosed herein provide increased semiconductor device yields.

[0126] An embodiment of the present disclosure is a method for manufacturing a semiconductor device, the method including forming a multilayer photoresist structure above a substrate, the multilayer photoresist structure including a metal-containing photoresist. The multilayer photoresist structure includes two or more metal-containing photoresist layers with different physical parameters. The metal-containing photoresist is a reaction product of a first precursor and a second precursor, and each layer of the multilayer photoresist structure is formed using different photoresist layer formation parameters. The different photoresist layer formation parameters are one or more selected from the group consisting of: a first precursor, an amount of the first precursor, a second precursor, an amount of the second precursor, a length of time for each photoresist layer formation operation, and a heating condition for the photoresist layer. The multilayer photoresist structure is selectively exposed to actinic radiation to form a latent pattern, and the latent pattern is developed by applying a developer to the selectively exposed multilayer photoresist structure to form a pattern. In one embodiment, the actinic radiation is extreme ultraviolet radiation. In one embodiment, the method includes post-exposure heating the multilayer photoresist structure at a temperature in the range of 50°C to 250°C after selectively exposing the multilayer photoresist structure to actinic radiation to form a latent pattern and before developing the latent pattern. In one embodiment, the method includes heating each photoresist layer at a temperature in the range of 50°C to 200°C after forming each layer. In one embodiment, the different physical parameters of the photoresist layers include different photoresist layer crosslink densities or different photoresist layer thicknesses. In one embodiment, the multilayer photoresist structure is formed by chemical vapor deposition (CVD) or atomic layer deposition (ALD). In one embodiment, a multilayer photoresist structure includes a first photoresist layer covering a substrate and a second photoresist layer covering the first photoresist layer, the photoresist layer being a reaction product of a first precursor and a second precursor, the first photoresist layer being formed by combining a second precursor having a first concentration with a first precursor, and the second photoresist layer being formed by combining a second precursor having a second concentration with a first precursor, wherein the first concentration and the second concentration of the second precursor are different. In one embodiment, the method includes forming a third photoresist layer over the second photoresist layer, wherein the third photoresist layer is formed by combining a second precursor having a third concentration with a first precursor, and the third concentration is different from the first concentration and the second concentration. In one embodiment, the amount of H2O present during formation of the multilayer photoresist structure over the substrate is varied to provide two or more photoresist layers having different physical parameters. In one embodiment, the two or more photoresist layers have different thicknesses. In one embodiment, the method includes performing a heating operation after forming each of the two or more photoresist layers.

[0127] Another embodiment of the present disclosure is a method for forming a pattern, the method comprising: forming a first resist layer having a first physical parameter on a substrate; and forming a second resist layer having a second physical parameter on top of the first resist layer. The first physical parameter and the second physical parameter are different. The first resist layer and the second resist layer are cross-linked pattern by pattern, and the uncross-linked portions of the first resist layer and the second resist layer are removed to form patterns in the first resist layer and the second resist layer. The first resist layer and the second resist layer are reaction products of a first metal-containing precursor and a second precursor. The first resist layer and the second resist layer are formed using different resist layer formation parameters. The different resist layer formation parameters are one or more selected from the group consisting of: a first metal-containing precursor, an amount of the first metal-containing precursor, a second precursor, an amount of the second precursor, a length of time for each resist layer formation operation, and a heating condition of the resist layer. In one embodiment, the method comprises forming a third resist layer having a third physical parameter on top of the second resist layer, wherein the third physical parameter is different from the first physical parameter and the second physical parameter. In one embodiment, the first physical parameter and the second physical parameter are the crosslink density of the first resist layer and the second resist layer. In one embodiment, the first physical parameter and the second physical parameter are the thickness of the first resist layer and the second resist layer. In one embodiment, the method includes heating the first resist layer and the second resist layer after forming each resist layer. In one embodiment, the uncrosslinked portions of the first resist layer and the second resist layer are removed by a dry etching operation. In one embodiment, the first resist layer and the second resist layer are formed by atomic layer deposition (ALD) or chemical vapor deposition (CVD). In one embodiment, crosslinking the first resist layer and the second resist layer pattern by pattern includes exposing the first resist layer and the second resist layer pattern by pattern to actinic radiation, and heating the first resist layer and the second resist layer after pattern by pattern exposure. In one embodiment, the actinic radiation includes extreme ultraviolet radiation or an electron beam. In one embodiment, the temperature of heating the first resist layer and the second resist layer is 50°C to 250°C.

[0128] Another embodiment of the present disclosure is a method for forming a pattern, the method comprising: forming a first photoresist layer on a substrate by depositing a first photoresist composition with a first deposition parameter in a first vapor deposition operation, and forming a second photoresist layer on the first photoresist layer by depositing a second photoresist composition with a second deposition parameter in a second vapor deposition operation. The first deposition parameter is different from the second deposition parameter. The first deposition parameter and the second deposition parameter are one or more selected from the group consisting of: the amount of the first photoresist composition, the amount of the second photoresist composition, the length of time of each photoresist layer forming operation, the pressure, the vapor flow rate, and the heating conditions of the photoresist layer. The first photoresist layer and the second photoresist layer are selectively exposed to actinic radiation to form a latent pattern. The latent pattern is developed by applying a developer to the selectively exposed first photoresist layer and the second photoresist layer to form a pattern. In one embodiment, the first vapor deposition operation and the second vapor deposition operation are atomic layer deposition (ALD) or chemical vapor deposition (CVD). In one embodiment, the method includes forming a third photoresist layer over the second photoresist layer by a third vapor deposition operation at a third deposition parameter, wherein the third deposition parameter is different from the first deposition parameter and the second deposition parameter. In one embodiment, the amount of the third deposition parameter is between the amount of the first deposition parameter and the amount of the second deposition parameter. In one embodiment, the actinic radiation is extreme ultraviolet radiation or an electron beam. In one embodiment, the method includes post-exposure heating of the first photoresist layer and the second photoresist layer at a temperature of 50° C. to 250° C. after selectively exposing the first photoresist layer and the second photoresist layer to actinic radiation to form a latent pattern and before developing the latent pattern. In one embodiment, the first photoresist layer and the second photoresist layer include a metal-containing photoresist composition. In one embodiment, the first photoresist layer and the second photoresist layer have different thicknesses. In one embodiment, the first photoresist layer and the second photoresist layer have different crosslink densities.

[0129] Another embodiment of the present disclosure is a method for manufacturing a semiconductor device, the method comprising forming a first photoresist layer over a substrate by performing a vapor deposition operation at a first water vapor concentration in a deposition chamber. Forming a second photoresist layer over the first photoresist layer by performing a second vapor deposition operation at a second water vapor concentration in the deposition chamber. The first water vapor concentration and the second water vapor concentration are different. The first photoresist layer and the second photoresist layer are selectively exposed to actinic radiation to form a latent pattern. The latent pattern is developed by applying a developer to the selectively exposed first photoresist layer and the second photoresist layer to form a pattern. In one embodiment, the second water vapor concentration is greater than the first water vapor concentration. In one embodiment, the first water vapor concentration is greater than the second water vapor concentration. In one embodiment, the method comprises forming a third photoresist layer on the second photoresist layer by performing a third vapor deposition operation at a third water vapor concentration, wherein the third water vapor concentration is different from the first water vapor concentration and the second water vapor concentration. In one embodiment, the second water vapor concentration is greater than the first water vapor concentration, and the third water vapor concentration is greater than the second water vapor concentration. In one embodiment, the first water vapor concentration is greater than the second water vapor concentration, and the second water vapor concentration is greater than the third water vapor concentration. In one embodiment, the deposition chamber is an atomic layer deposition chamber or a chemical vapor deposition chamber. In one embodiment, the developer is a plasma etchant. In one embodiment, the method includes etching the exposed portion of the substrate after developing the latent pattern.

[0130] Another embodiment of the present disclosure is a method of manufacturing a semiconductor device, including depositing a reaction product of an organometallic precursor and a second precursor over a substrate to form a first resist layer over the substrate, the first resist layer having a first concentration of the second precursor. The reaction product of the organometallic precursor and the second precursor is deposited over the first resist layer to form a second resist layer, the second resist layer having a second concentration of the second precursor. The second concentration is different from the first concentration. The organometallic precursors each independently have the formula: a R b X c, wherein M is one or more selected from Sn, Bi, Sb, In and Te; R is a substituted or unsubstituted alkyl, alkenyl or carboxylate group; X is a halogen or sulfonate group, and 1≤a≤2, b≥1, c≥1, and b+c≤5. The second precursor is independently selected from water, amine, borane and phosphine. The first resist layer and the second resist layer are cross-linked pattern by pattern to form a latent pattern in the first resist layer and the second resist layer. The latent pattern is developed by applying a developer to the first resist layer and the second resist layer that are cross-linked pattern by pattern to form a pattern that exposes a portion of the substrate. In one embodiment, the second concentration is greater than the first concentration. In one embodiment, the first concentration is greater than the second concentration. In one embodiment, the method includes depositing a reaction product of an organometallic precursor and a second precursor over the second resist layer before pattern by pattern cross-linking to form a third resist layer over the second resist layer, the third resist layer having a third concentration of the second precursor, wherein the third concentration is different from the first concentration and the second concentration. In one embodiment, the second concentration is greater than the first concentration, and the third concentration is greater than the first concentration. In one embodiment, the first concentration is greater than the second concentration, and the second concentration is greater than the third concentration. In one embodiment, the first resist layer, the second resist layer, and the third resist layer are formed by the same organic metal precursor. In one embodiment, the first resist layer, the second resist layer, and the third resist layer are formed by the same second precursor. In one embodiment, pattern-by-pattern crosslinking of the resist layer includes: exposing the first resist layer and the second resist layer to extreme ultraviolet radiation pattern by pattern; and heating the first resist layer and the second resist layer exposed pattern by pattern. In one embodiment, the heating is performed at a temperature ranging from 50°C to 250°C. In one embodiment, the amine is ammonia or hydrazine. In one embodiment, the amine, borane, or phosphine comprises a halide substituent.

[0131] Another embodiment is a method of manufacturing a semiconductor device, the method including depositing a reaction product of an organometallic precursor and a second precursor over a substrate by a vapor deposition operation to form a first photoresist layer over the substrate, the first photoresist layer having a first concentration of the second precursor. Depositing the reaction product of the organometallic precursor and the second precursor over the first photoresist layer by a vapor deposition operation to form a second photoresist layer over the first photoresist layer, the second photoresist layer having a second concentration of the second precursor. The second concentration is different from the first concentration. The organometallic precursors are each independently of the formula: a R b X c, wherein M is one or more selected from Sn, Bi, Sb, In and Te; R is a substituted or unsubstituted alkyl, alkenyl or carboxylate group; X is a halogen or sulfonate group; and 1≤a≤2, b≥1, c≥1, and b+c≤5. The second precursors are each independently selected from water, amines, boranes and phosphines. The first photoresist layer and the second photoresist layer are selectively exposed to actinic radiation to form a latent pattern in the first photoresist layer and the second photoresist layer. The latent pattern is developed by applying a developer to the selectively exposed first photoresist layer and the second photoresist layer to form a pattern that exposes a portion of the substrate. In one embodiment, the method includes depositing a reaction product of an organometallic precursor and a second precursor over the second photoresist layer by a vapor deposition operation before selectively exposing the first precursor and the second precursor to form a third photoresist layer, the third photoresist layer having a third concentration of the second precursor, wherein the third concentration is different from the first concentration and the second concentration. In one embodiment, the method includes heating the first photoresist layer, the second photoresist layer, and the third photoresist layer at a temperature ranging from 50°C to 250°C after selectively exposing and before developing the latent pattern. In one embodiment, the vapor deposition operation is selected from chemical vapor deposition or atomic layer deposition. In one embodiment, the method includes heating the first photoresist layer, the second photoresist layer, and the third photoresist layer at a temperature ranging from 50°C to 200°C after forming each of the first photoresist layer, the second photoresist layer, and the third photoresist layer and before selective exposure. In one embodiment, the first photoresist layer, the second photoresist layer, and the third photoresist layer have different thicknesses. In one embodiment, X is a sulfonate group substituted with one or more amine groups. In one embodiment, an alkyl, alkenyl, or carboxylate group is substituted with one or more fluorine groups. In one embodiment, an amine, borane, or phosphine comprises a halide substituent. In one embodiment, the actinic radiation is extreme ultraviolet radiation or an electron beam.

[0132] Another embodiment of the present disclosure is a method of manufacturing a semiconductor device, comprising: depositing a first photoresist layer over a substrate by atomic layer deposition (ALD) or chemical vapor deposition (CVD), and depositing a second photoresist layer over the first photoresist layer by ALD or CVD. The first photoresist layer comprises a first photoresist composition comprising a first reaction product of a first compound and a second compound, and the second photoresist layer comprises a second photoresist composition comprising a second reaction product of the first compound and the second compound. The first compound is independently selected from tert-butyl tris (dimethylamino) tin, isobutyl tris (dimethylamino) tin, n-butyl tris (dimethylamino) tin, sec-butyl tris (dimethylamino) tin, isopropyl tris (dimethylamino) tin, n-propyl tris (diethylamino) tin, tert-butyl tris (tert-butoxy) tin, isobutyl tris (butoxy) tin, n-butyl tris (butoxy) tin, sec-butyl tris (butoxy) tin, isopropyl (tri) dimethylamino tin and n-propyl tris (butoxy) tin. The second compound is independently selected from water, amine, borane and phosphine. The concentration of the second compound in the first photoresist composition is different from the concentration of the second compound in the second photoresist composition. The first photoresist layer and the second photoresist layer are selectively exposed to actinic radiation to form a latent pattern. The latent pattern is developed by applying a developer to the selectively exposed first photoresist layer and the second photoresist layer to form a pattern of a portion of the exposed substrate. In one embodiment, the method includes removing a portion of the substrate exposed by development. In one embodiment, removing a portion of the substrate exposed by development includes etching the substrate. In one embodiment, the actinic radiation is extreme ultraviolet radiation or an electron beam. In one embodiment, the method includes heating the first photoresist layer and the second photoresist layer at a temperature in the range of 50° C. to 250° C. after selectively exposing the first photoresist layer and the second photoresist layer to actinic radiation to form a latent pattern and before developing the latent pattern. In one embodiment, the first compound is substituted with one or more fluorine groups. In one embodiment, the first compound in the first photoresist composition is the same as the first compound in the second photoresist composition. In one embodiment, the second compound in the first photoresist composition is the same as the second compound in the second photoresist composition. In one embodiment, the method includes depositing a third photoresist layer over the second photoresist layer via ALD or CVD, wherein the third photoresist layer comprises a third photoresist composition, the third photoresist composition comprising a third reaction product of a first compound and a second compound, and a concentration of the second compound in the third photoresist composition is greater than a concentration of the second compound in the second photoresist composition, and a concentration of the second compound in the second photoresist composition is greater than a concentration of the second compound in the first photoresist composition.In one embodiment, the method includes depositing a third photoresist layer over the second photoresist layer via ALD or CVD, wherein the third photoresist layer comprises a third photoresist composition, the third photoresist composition comprising a third reaction product of a first compound and a second compound, and the concentration of the second compound in the third photoresist composition is less than the concentration of the second compound in the second photoresist composition, and the concentration of the second compound in the second photoresist composition is less than the concentration of the second compound in the first photoresist composition. In one embodiment, the amine is ammonia or hydrazine. In one embodiment, the amine, borane or phosphine comprises a halide substituent.

[0133] Another embodiment of the present disclosure is a method for manufacturing a semiconductor device, including forming a multilayer resist structure over a substrate, wherein the multilayer resist structure includes two or more resist layers. Each of the two or more resist layers comprises a reaction product of an organic metal compound and a compound selected from water, an amine, a borane, and a phosphine. Each of the two or more resist layers has different physical parameters. The multilayer resist structure is cross-linked pattern by pattern to form a latent pattern in the multilayer resist structure. The latent pattern is developed by applying a developer to the multilayer resist structure layer cross-linked pattern by pattern to form a pattern in the multilayer resist structure. In one embodiment, the cross-linking multilayer resist structure pattern by pattern includes exposing two or more resist layers to actinic radiation pattern by pattern, and heating the two or more resist layers after the pattern by pattern exposure. In one embodiment, the actinic radiation includes extreme ultraviolet radiation or an electron beam. In one embodiment, heating the two or more resist layers includes heating the two or more resist layers at a temperature in the range of 50°C to 250°C. In one embodiment, the physical parameter is the cross-linking density of the two or more resist layers. In one embodiment, the physical parameter is the thickness of the two or more resist layers. In one embodiment, the organometallic compound has the formula: M a R b X c , wherein M is selected from one or more of Sn, Bi, Sb, In and Te; R is a substituted or unsubstituted alkyl, alkenyl or carboxylate group; X is a halogen or sulfonate group; 1≤a≤2, b≥1, c≥1, b+c≤5. In one embodiment, the alkyl, alkenyl or carboxylate group is substituted with one or more fluorine groups. In one embodiment, the sulfonate group is substituted with one or more amine groups. In one embodiment, the two or more resist layers include 3 to 6 resist layers. In one embodiment, the amine is ammonia or hydrazine. In one embodiment, the amine, borane or phosphine comprises a halide substituent.

[0134] Another embodiment of the present disclosure is a method for forming a pattern, the method comprising: forming a first photoresist layer over a substrate, and forming a second photoresist layer over the first photoresist layer. Forming a third photoresist layer over the second photoresist layer. Forming a fourth photoresist layer over the third photoresist layer. Forming a fifth photoresist layer over the fourth photoresist layer. The first photoresist layer, the second photoresist layer, the third photoresist layer, the fourth photoresist layer, and the fifth photoresist layer have different physical parameters, and the first photoresist layer, the second photoresist layer, the third photoresist layer, the fourth photoresist layer, and the fifth photoresist layer form a multilayer photoresist structure. The multilayer photoresist structure is selectively exposed to actinic radiation to form a latent pattern. The latent pattern is developed by applying a developer to the selectively exposed multilayer photoresist structure to form a pattern. In one embodiment, the actinic radiation is extreme ultraviolet radiation. In one embodiment, the method includes post-exposure heating the multilayer photoresist structure at a temperature in the range of 50°C to 250°C after selectively exposing the multilayer photoresist structure to actinic radiation to form a latent pattern and before developing the latent pattern. In one embodiment, the photoresist layer includes a metal-containing photoresist composition. In one embodiment, the different physical parameters of the photoresist layers include different crosslink densities or different photoresist layer thicknesses. In one embodiment, the first photoresist layer has a first crosslink density, the second photoresist layer has a second crosslink density, the third photoresist layer has a third crosslink density, the fourth photoresist layer has a fourth crosslink density, and the fifth photoresist layer has a fifth crosslink density, the second crosslink density is greater than the first crosslink density, the third crosslink density, and the fourth crosslink density, and the third crosslink density is greater than the first crosslink density and the fourth crosslink density. In one embodiment, the method includes performing a heating operation after forming each of the first photoresist layer, the second photoresist layer, the third photoresist layer, the fourth photoresist layer, and the fifth photoresist layer.

[0135] Some exemplary implementations are described below:

[0136] Embodiment 1. A method for manufacturing a semiconductor device, comprising:

[0137] forming a multi-layer photoresist structure including a metal-containing photoresist over the substrate,

[0138] wherein the multilayer photoresist structure comprises two or more metal-containing photoresist layers having different physical parameters,

[0139] wherein the metal-containing photoresist is a reaction product of a first precursor and a second precursor, and

[0140] wherein different photoresist layer formation parameters are used to form each layer of the multi-layer photoresist structure,

[0141] wherein the different photoresist layer formation parameters are one or more selected from the group consisting of: a first precursor, an amount of the first precursor, a second precursor, an amount of the second precursor, a time length of each photoresist layer formation operation, and a heating condition of the photoresist layer;

[0142] selectively exposing the multilayer photoresist structure to actinic radiation to form a latent pattern; and

[0143] The latent pattern is developed by applying a developer to the selectively exposed multi-layer photoresist structure to form a pattern.

[0144] Embodiment 2. The method of embodiment 1, wherein the actinic radiation is extreme ultraviolet radiation.

[0145] Embodiment 3. The method according to embodiment 1 also includes post-exposure heating of the multilayer photoresist structure at a temperature of 50°C to 250°C after selectively exposing the multilayer photoresist structure to actinic radiation to form a latent pattern and before developing the latent pattern.

[0146] Embodiment 4. The method of embodiment 1, further comprising heating each photoresist layer at a temperature ranging from 50° C. to 200° C. after forming each layer.

[0147] Embodiment 5. The method of embodiment 1, wherein the different physical parameters of the photoresist layer include different cross-linking densities or different photoresist layer thicknesses.

[0148] Embodiment 6. The method of embodiment 1, wherein the multilayer photoresist structure is formed by chemical vapor deposition (CVD) or atomic layer deposition (ALD).

[0149] Embodiment 7. The method of embodiment 1, wherein:

[0150] The multi-layer photoresist structure comprises a first photoresist layer covering the substrate and a second photoresist layer covering the first photoresist layer.

[0151] The photoresist layer is a reaction product of a first precursor and a second precursor,

[0152] forming the first photoresist layer by combining a second precursor having a first concentration with the first precursor,

[0153] forming the second photoresist layer by combining a second precursor having a second concentration with the first precursor, and

[0154] The first concentration and the second concentration of the second precursor are different from each other.

[0155] Embodiment 8. The method of embodiment 7 further comprising forming a third photoresist layer over the second photoresist layer,

[0156] wherein the third photoresist layer is formed by combining a second precursor having a third concentration with a first precursor, and

[0157] The third concentration is different from the first concentration and the second concentration.

[0158] Embodiment 9. The method of embodiment 1, wherein the amount of H 2 O present during formation of the multilayer photoresist structure on the substrate is varied to provide the two or more photoresist layers with different physical parameters.

[0159] Embodiment 10. The method of embodiment 1, wherein the two or more photoresist layers have different thicknesses.

[0160] Embodiment 11. The method of embodiment 1, further comprising performing a heating operation after forming each of the two or more photoresist layers.

[0161] Embodiment 12. A method of forming a pattern, comprising:

[0162] forming a first resist layer having first physical parameters on the substrate;

[0163] forming a second resist layer having a second physical parameter over the first resist layer, wherein the first physical parameter and the second physical parameter are different;

[0164] cross-linking the first resist layer and the second resist layer pattern by pattern; and

[0165] removing uncrosslinked portions of the first resist layer and the second resist layer to form patterns in the first resist layer and the second resist layer,

[0166] wherein the first resist layer and the second resist layer are reaction products of a first metal-containing precursor and a second precursor,

[0167] wherein the first resist layer and the second resist layer are formed using different resist layer formation parameters,

[0168] The different resist layer formation parameters are one or more selected from the group consisting of: a first metal-containing precursor, an amount of the first metal-containing precursor, a second precursor, an amount of the second precursor, a length of time for each resist layer formation operation, and a heating condition for the resist layer.

[0169] Embodiment 13. The method according to embodiment 12 further includes: forming a third resist layer having a third physical parameter over the second resist layer, wherein the third physical parameter is different from the first physical parameter and the second physical parameter.

[0170] Embodiment 14. The method of embodiment 12, wherein the first physical parameter and the second physical parameter are crosslink densities of the first resist layer and the second resist layer.

[0171] Embodiment 15. The method of embodiment 12, wherein the first physical parameter and the second physical parameter are thicknesses of the first resist layer and the second resist layer.

[0172] Embodiment 16. The method of embodiment 12, further comprising heating the first resist layer and the second resist layer after forming each resist layer.

[0173] Embodiment 17. A method of forming a pattern, comprising:

[0174] forming a first photoresist layer on the substrate by depositing a first photoresist composition in a first vapor deposition operation with first deposition parameters;

[0175] forming a second photoresist layer on the first photoresist layer by depositing a second photoresist composition in a second vapor deposition operation with second deposition parameters,

[0176] wherein the first deposition parameter is different from the second deposition parameter, and

[0177] wherein the first deposition parameter and the second deposition parameter are one or more selected from the group consisting of: the amount of the first photoresist composition, the amount of the second photoresist composition, the length of time of each photoresist layer forming operation, the pressure, the vapor flow rate, and the heating conditions of the photoresist layer;

[0178] selectively exposing the first photoresist layer and the second photoresist layer to actinic radiation to form a latent pattern; and

[0179] The latent pattern is developed by applying a developer to the selectively exposed first photoresist layer and the second photoresist layer to form a pattern.

[0180] Embodiment 18. The method of embodiment 17, wherein the first vapor deposition operation and the second vapor deposition operation are atomic layer deposition (ALD) or chemical vapor deposition (CVD).

[0181] Embodiment 19. The method according to embodiment 17 further comprises: forming a third photoresist layer on the second photoresist layer by a third vapor deposition operation under a third deposition parameter,

[0182] The third deposition parameter is different from the first deposition parameter and the second deposition parameter.

[0183] Embodiment 20. The method of embodiment 19, wherein the amount of the third deposition parameter is between the amount of the first deposition parameter and the amount of the second deposition parameter.

[0184] The features of several embodiments or examples are summarized above so that those skilled in the art can better understand the various aspects of the present disclosure. Those skilled in the art should understand that they can easily use the present disclosure as a basis for designing or modifying other processes and structures to carry out the same purposes and / or achieve the same advantages as the embodiments or examples introduced herein. Those skilled in the art should also recognize that such equivalent constructions do not depart from the spirit and scope of the present disclosure, and that they can make various changes, substitutions and modifications herein without departing from the spirit and scope of the present disclosure.

Claims

1. A method for manufacturing a semiconductor device, comprising: forming a multi-layer photoresist structure including a metal-containing photoresist over the substrate, wherein the multilayer photoresist structure comprises two or more metal-containing photoresist layers having different physical parameters, wherein the metal-containing photoresist is a reaction product of a first precursor and a second precursor, and wherein different photoresist layer formation parameters are used to form each layer of the multi-layer photoresist structure, wherein the different photoresist layer formation parameters are one or more selected from the group consisting of: a first precursor, an amount of the first precursor, a second precursor, an amount of the second precursor, a time length of each photoresist layer formation operation, and a heating condition of the photoresist layer; selectively exposing the multilayer photoresist structure to actinic radiation to form a latent pattern; and The latent pattern is developed by applying a developer to the selectively exposed multi-layer photoresist structure to form a pattern.

2. The method according to claim 1, wherein: The actinic radiation is extreme ultraviolet radiation.

3. The method of claim 1 further comprising, after selectively exposing the multilayer photoresist structure to actinic radiation to form a latent pattern and before developing the latent pattern, subjecting the multilayer photoresist structure to post-exposure heating at a temperature of 50° C. to 250° C. 4 . The method of claim 1 , further comprising heating each photoresist layer at a temperature ranging from 50° C. to 200° C. after forming each layer.

5. The method according to claim 1, wherein: The different physical parameters of the photoresist layer include different cross-linking densities or different photoresist layer thicknesses.

6. The method according to claim 1, wherein: The multi-layer photoresist structure is formed by chemical vapor deposition or atomic layer deposition.

7. The method according to claim 1, wherein: The multi-layer photoresist structure comprises a first photoresist layer covering the substrate and a second photoresist layer covering the first photoresist layer. The photoresist layer is a reaction product of a first precursor and a second precursor, forming the first photoresist layer by combining a second precursor having a first concentration with the first precursor, forming the second photoresist layer by combining a second precursor having a second concentration with the first precursor, and The first concentration and the second concentration of the second precursor are different from each other.

8. The method according to claim 7, further comprising forming a third photoresist layer over the second photoresist layer, in, forming the third photoresist layer by combining the second precursor having a third concentration with the first precursor, and The third concentration is different from the first concentration and the second concentration.

9. The method of claim 1, wherein an amount of H2O present during formation of the multi-layer photoresist structure on the substrate is varied to provide the two or more photoresist layers with different physical parameters.

10. The method according to claim 1, wherein: The two or more photoresist layers have different thicknesses. 11 . The method of claim 1 , further comprising performing a heating operation after forming each of the two or more photoresist layers.

12. A method for forming a pattern, comprising: forming a first resist layer having first physical parameters on the substrate; forming a second resist layer having a second physical parameter over the first resist layer, wherein the first physical parameter and the second physical parameter are different; cross-linking the first resist layer and the second resist layer pattern by pattern; and removing uncrosslinked portions of the first resist layer and the second resist layer to form patterns in the first resist layer and the second resist layer, wherein the first resist layer and the second resist layer are reaction products of a first metal-containing precursor and a second precursor, wherein the first resist layer and the second resist layer are formed using different resist layer formation parameters, The different resist layer formation parameters are one or more selected from the group consisting of: a first metal-containing precursor, an amount of the first metal-containing precursor, a second precursor, an amount of the second precursor, a length of time for each resist layer formation operation, and a heating condition for the resist layer.

13. The method according to claim 12, further comprising: A third resist layer having a third physical parameter is formed over the second resist layer, wherein the third physical parameter is different from the first physical parameter and the second physical parameter.

14. The method according to claim 12, wherein: The first physical parameter and the second physical parameter are crosslinking densities of the first resist layer and the second resist layer.

15. The method according to claim 12, wherein: The first physical parameter and the second physical parameter are thicknesses of the first resist layer and the second resist layer. 16 . The method of claim 12 , further comprising heating the first resist layer and the second resist layer after forming each resist layer.

17. A method for forming a pattern, comprising: forming a first photoresist layer on the substrate by depositing a first photoresist composition in a first vapor deposition operation with first deposition parameters; forming a second photoresist layer on the first photoresist layer by depositing a second photoresist composition in a second vapor deposition operation with second deposition parameters, wherein the first deposition parameter is different from the second deposition parameter, and wherein the first deposition parameter and the second deposition parameter are one or more selected from the group consisting of: the amount of the first photoresist composition, the amount of the second photoresist composition, the length of time of each photoresist layer forming operation, the pressure, the vapor flow rate, and the heating conditions of the photoresist layer; selectively exposing the first photoresist layer and the second photoresist layer to actinic radiation to form a latent pattern; and The latent pattern is developed by applying a developer to the selectively exposed first photoresist layer and the second photoresist layer to form a pattern.

18. The method according to claim 17, wherein: The first vapor deposition operation and the second vapor deposition operation are atomic layer deposition (ALD) or chemical vapor deposition (CVD).

19. The method according to claim 17, further comprising: forming a third photoresist layer on the second photoresist layer by a third vapor deposition operation under a third deposition parameter, The third deposition parameter is different from the first deposition parameter and the second deposition parameter.

20. The method according to claim 19, wherein: The amount of the third deposition parameter is between the amount of the first deposition parameter and the amount of the second deposition parameter.

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