Hybrid topographic and chemical prestructures for guided self-assembly of block copolymers

Abstract

A process that exhibits: i) Forming a layer (21), hereinafter referred to as the SA layer, which has a self-assembly material, hereinafter referred to as the SA material, on an upper surface of a hybrid prestructure, and forming a cover layer (174) which is arranged on an upper surface of the SA layer (21), wherein the SA material for self-organization to form a phase-separated lamellar area structure (31) with a characteristic pitch Lo is formed, the prestructure is arranged on a substrate (60), the upper surface (13) of the prestructure has a geometric principal axis, the upper surface of the prestructure comprises a) independent raised surfaces (13) interspersed with adjacent recessed surfaces (14) and b) side walls (18) connecting the raised surfaces (13) with the recessed surfaces (14), the material located under the raised surfaces (13) of the prestructure has a higher etch resistance in a specific etching process compared to the material located under the recessed surfaces (14) of the prestructure, a certain raised surface (13) a width W E has, which is defined as the length of the determined raised surface (13) in a direction perpendicular to the principal axis, a specific recessed surface (14) a width W R has, which is defined as the length of the recessed surface (14) in a direction perpendicular to the principal axis, W R +W E for each pair of adjacent recessed and raised surfaces (13, 14) there is an independent sum with a value of approximately nLo, where n is an integer from 4 to approximately 30, W R of at least one of the recessed surfaces (14) is larger than about 2 Lo, W Eof at least one of the raised surfaces (13) is larger than about 2 Lo, each of the side walls (18) has an independent height H N from about 0.1 Lo to about 2 Lo, the SA layer (21) is in contact with the raised surfaces (13), the recessed surfaces (14) and the side walls (18) of the prestructure, and the SA layer (21) has an upper surface in contact with the topmost coating; ii) Enabling or inducing the self-organization of the SA material, thereby forming a self-organized SA layer (21) having the lamellar region structure, wherein the region structure has alternating regions (32, 33) each having chemically different components of the SA material, wherein each of the regions has a plurality of lamellae, wherein the raised surfaces (13) are neutral-wetting for the areas (32,33), each of the raised surfaces (13) touches at least one of the lamellae of each of the areas (32, 33), each of the lamellae in contact with a given raised surface (13) of the prestructure is a) oriented perpendicular to the given raised surface (13), b) in contact with the cover layer above the given raised surface (13), and c) oriented along the principal axis of the prestructure. iii) selective removal of one of the areas (32, 33) by means of an etching process, thereby forming an etched area structure that has the lamellae of a remaining area; and iv) selectively transferring the etched area structure into the material with a higher etch resistance under the raised surfaces (13) by means of a second etching process, thereby forming a transfer structure which has topographic features which material with a higher etch resistance has.

Description

BACKGROUND

[0001] The present invention relates to hybrid topographical and chemical precursors for guided self-assembly of block copolymers, and more particularly to precursors that support perpendicular alignment of self-assembled domain structures across precursor regions having different etching properties.

[0002] Directed self-assembly (DSA) of block copolymers (BCPs) is a promising resolution-enhancing technology for patterning extension. Chemical epitaxy, a form of DSA, has proven reliable in generating dense gratings and hexagonal arrays from sparsely populated chemical precursors that feature a guiding region (a non-neutral, alignment-transferring region with preferential affinity to a domain) and a non-guiding region (neutral region) that supports perpendicular alignment of the BCP domains. In chemical epitaxy for a block copolymer with a bulk periodicity (pitch) Lo ("L zero"), the width of the alignment-transferring regions can be approximately 0.5 Lo (i.e., 0.5 times Lo) or approximately 1.5 Lo.

[0003] For example, in a report on a systematic investigation of chemical epitaxy using a chemical precursor with a pitch of 3 Lo for 3x density multiplication (i.e., threefold density multiplication), where the precursor was formed of cross-linked polystyrene as the guiding region and a neutral material as the non-guiding region supporting perpendicular alignment, good DSA was achieved only when the width of the alignment transfer region of the precursor was 0.4 Lo to 0.8 Lo, or about 1.3 Lo (Detcheverry, et al., Macromolecules, 2010, Vol. 43, pages 3446-3454; Rincon, et al., “Determination of Critical Parameters for Control of Directed Self-Assembly of Block Copolymers Using Frequency Multiplication,” 2012 Report of SRC Annual Review, University of Chicago). When the width of the alignment transfer region was outside this range of values, good DSA was not obtained.Furthermore, when the alignment transfer area was larger than 2 Lo, good DSA was not obtained. Instead, inverted regions and defects were observed.

[0004] Many patterning applications require complex adjustment of dense DSA structures. Recently, adjustments of dense DSA arrays using a separate cutting layer have been implemented using two different approaches: adjustment before DSA layer formation ("cut-first") and adjustment after DSA layer formation ("cut-last").

[0005] Cut-first schemes that utilize buried alignment levels beneath the DSA guide layer have been demonstrated (Sayan et al., "Directed Self-Assembly Process Integration - Fin Patterning Approaches and Challenges," Proc. of SPIE, Advances in Patterning Materials and Processes XXXI, 2014, Vol. 9051, 90510M). Cut-last alignment of 42 nm line-space DSA structures after DSA with a dedicated mask has also been demonstrated (Liu et al., "Towards electrically testable SOI devices using Directed Self-Assembly for fin formation," Proc. SPIE 9049, Alternative Lithographic Technologies VI, 904909, 2014). However, as the pitch of DSA structures decreases, alignment of the DSA structure becomes more difficult due to the dense overlay frame.

[0006] Furthermore, document US 2014 / 0 335 324 A1 discloses a template for aligning a pattern in a block polymer film and a method for producing the pattern. Furthermore, document US 2004 / 0 295 669 A1 discloses a pattern-forming method in which a first conductive layer is formed on a previously processed layer. Additionally, phase separation of a first self-structuring material using the first conductive layer is described.

[0007] There is a need for multilayer pre-structures that support the self-aligned adaptation of perpendicularly aligned DSA domain structures over regions having different wetting properties and etch characteristics with wide design spaces to create self-aligned adapted transfer structures that minimize the need for aligning separate cutting layers. OVERVIEW

[0008] This object is achieved by the subject matter of the independent claims. Further embodiments are described by the respective dependent claims.

[0009] The features and advantages of the present invention described in the claims and others will be recognized and understood by those skilled in the art from the following detailed description, the drawings and the appended claims. BRIEF DESCRIPTION OF THE DIFFERENT VIEWS OF THE DRAWINGS Fig. Figure 1A shows Scheme 1, which illustrates an arrangement of blocks of a diblock polymer after self-assembly of the diblock polymer on a sublayer. Fig. Figure 1B shows Scheme 2, which is a schematic representation of vertically aligned lamellar regions of a self-assembled block copolymer or sublayer. Fig. Figure 1C is a cross-sectional diagram illustrating an exemplary three-layer hybrid prestructure, and Fig. Figure 1D is a top view of the hybrid pre-structure of Fig. 1C. Fig. 2A to 2E are cross-sectional layer diagrams illustrating a process of forming a self-aligned matched transfer structure with a hybrid pre-structure. Fig. 3A to 3E are cross-sectional layer diagrams illustrating Process 1 (basic method) of forming a hybrid prestructure. Fig. 4A to 4C are cross-sectional layer diagrams illustrating Method 2 of forming a hybrid pre-structure using a filler layer. Fig. 5A to 5B are cross-sectional layer diagrams illustrating Method 3 of forming a hybrid pre-structure by surface modification. Fig. 6A to 6B are cross-sectional layer diagrams illustrating Method 4 of forming a hybrid pre-structure by means of a double surface modification. Fig. 7A to 5B are cross-sectional layer diagrams illustrating Method 5 of forming a hybrid precursor by surface modification of a photoresist. Fig. Figure 8 is a series of scanning electron microscope (SEM) cross-sectional images showing well-guided self-assembly (DSA) over hybrid pre-structures of the first example with different width combinations of the raised surfaces (W E ) and the recessed surfaces (W R ). The hybrid prestructure of the first example was produced by the filling process (method 2). W E and W R were determined by integral multiples of the volume periodicity, Lo, of the block copolymer with different values ​​of W E +W R= 6 Lo, 7 Lo and 8 Lo. A good DSA was found for W E with a value of about 2 Lo to about 5 Lo. Fig. Figure 9 is a series of top-view SEM images showing an exemplary process window for good DSA (2nd example). A process window of about 10 nm for W E was observed in each of three different cases in which W E equal to approximately 2 Lo, 3 Lo and 4 Lo at a constant of W E +W R = 6 Lo. Fig. Figure 10A is a series of cross-sectional layer diagrams illustrating the process flow of the third example of i) preparing two hybrid precursors labeled "wide" and "narrow" from a patterned photoresist / stack (step 3), ii) using the precursors to form a perpendicularly aligned region structure by guided self-assembly (step 4), and iii) transferring the resulting structure to form a matched row structure (step 5). The numbering of the steps is shown in the rectangular box below each layer diagram. Fig. Figure 10B is a pair of SEMs labeled “wide” and “narrow” of the hybrid prestructures obtained by the process of Fig. 10A (3rd example). The “3” in the field corresponds to the third step in Fig. 10A. Fig. Figure 10C is a pair of SEMs labeled “wide” and “narrow” of self-assembled row structures (DSA structures) prepared using the hybrid prestructures of Fig. 10B (3rd example). The “4” in the field corresponds to the fourth step in Fig. 10A. Fig. 10D is a pair of SEMs labeled “wide” and “narrow” of transfer structures (DSA structures) made using the hybrid pre-structures of Fig. 10C (3rd example). The “5” in the field corresponds to the fifth step in Fig. 10A. Fig. 11A-11C are top-down SEMS images of DSA structures formed using hybrid pre-structures of the fourth example, which was fabricated by surface modification of the recessed surfaces. The width W E of the raised strip and the width W R of the adjacent depressed strip were measured with a constant of W E +WR = 8 Lo varied. Each of the DSA structures was a unidirectional array structure. Fig. 11A: 5 polystyrene (PS) lines are aligned on the raised stripes on the SiARC stripes and 3 PS lines are aligned on the recessed stripe. Fig. 11B: 5 PS lines are aligned on the raised stripes on SiARC and 2 PS lines are aligned on the recessed stripes. Fig. 11C: 4 PS lines are aligned on the raised stripes on SiARC and 4 PS lines are aligned on the recessed stripes. Fig. Figure 12 is a series of top-view SEMs depicting a row structure obtained from each process step of forming a customized array structure (Example 5). The hybrid precursors of the fifth example were fabricated by surface modification of the recessed surfaces using a brush polymer. Fig. Figure 13A is a series of images illustrating a two-dimensional fitting (Example 6A) for forming a target structure with a modulated line cut. The hybrid pre-structure was fabricated by surface modification of a photoresist feature (HSQ photoresist). The images include the 2D target structure, the corresponding SEM images of the photoresist structure in top view, the DSA structure, and fitting results after transferring the DSA structure. The transfer structure included various tapers in the line cut target. Fig. Figure 13B is a series of images illustrating a two-dimensional fit (Example 6B) for forming a target structure "IBM." The hybrid pre-structure was created by surface modification of a photoresist feature (HSQ photoresist). The images include the 2D target structure, the corresponding top-view SEM images of the photoresist structure, the DSA structure, and the fit results after transferring the DSA structure to the photoresist layer. The transfer structure included the IBM logo. Fig. Figure 13C is a series of images showing a two-dimensional alignment (Example 6C) using a target structure with a long, single-row taper consisting of a combination of three alternating rows with a three-row spacing. The hybrid pre-structure was fabricated using the fill-in process. The images include the 2D target structure, the corresponding top-view SEM image of the photoresist structure, the DSA structure, and alignment results after transferring the DSA structure to the photoresist layer. The final arrangement contains a three-row spacing and a single-row taper. DETAILED DESCRIPTION

[0010] Disclosed are hybrid precursors for forming customized lithographic array structures using guided self-assembly (DSA). The top surface of a hybrid precursor (referred to as a "precursor") has a geometric major axis. The top surface has independent raised surfaces interspersed with adjacent recessed surfaces and sidewalls of height H. Nthat connect the recessed surfaces to the raised surfaces. The materials underlying the raised surfaces have a higher etch resistance compared to materials underlying the recessed surfaces of the pre-structure in a given etch process. The surface properties of the raised and recessed surfaces may differ, as described in more detail below. A self-assembly (SA) layer comprising an SA material (e.g., block copolymer) designed to form lamellar regions is disposed on the upper surface of the pre-structure. That is, the SA layer has a greater thickness than H Nand is in contact with the raised surfaces, the depressed surfaces, and the sidewalls of the pre-structure. Self-assembly forms a lamellar domain structure in which the lamellae above the raised surfaces of the pre-structure are oriented perpendicularly with respect to the principal plane of the raised surface and along the principal axis of the pre-structure. The lamellae above the depressed surfaces can have a perpendicular orientation and / or a parallel orientation with respect to the principal plane of the depressed surface. Preferably, the sidewalls are in contact with a domain after self-assembly. The topology and surface properties of the pre-structure influence the self-assembly of the SA material and the global alignment of the domains.The etching contrast between the underlying materials of the raised and recessed surfaces enables the formation of customized transfer structures (e.g., unidirectional row-space arrays, two-dimensional structures). Methods for the formation and use of hybrid pre-structures are also disclosed.

[0011] An "SA material" is a material designed to self-assemble into phase-separated regions with different compositions. The SA material preferably comprises a block copolymer (BCP). Non-limiting block copolymers include diblock and triblock copolymers. An "SA layer" is a layer comprising an SA material. The SA layer is disposed on the top surface of the prestructure and is in contact with the raised surfaces, the recessed surfaces, and the sidewalls of the prestructure. Generally, the SA layer can have a thickness of about 5 nm to about 500 nm above the raised surfaces, more particularly, over 20 nm to over 50 nm.

[0012] The term "pre-structure" refers to the collection of surfaces on which the SA layer is arranged for self-assembly. The raised surfaces, recessed surfaces, and sidewalls of the top surface of the pre-structure are in contact with the SA layer. The SA layer also has a top surface in contact with the atmosphere.

[0013] Optionally, a capping layer can be applied to the top surface of the SA layer prior to self-assembly to control the alignment for the self-assembled regions. Alternatively, a capping layer can be formed by self-assembly of the SA layer (i.e., the SA layer has an embedded capping layer). In this case, a component of the SA layer undergoes phase separation to form a separate and distinct layer at the atmosphere interface of the SA layer, thereby forming a capping layer on other phase-separated regions of the self-assembled SA layer. The capping layer can be made of any material that allows self-assembly of the SA layer to form perpendicularly aligned regions in contact with and above the raised surfaces of the prestructure.

[0014] A "graphoepitaxial pre-structure" is a pre-structure where the topography and surface properties influence self-assembly. A "chemical pre-structure" is a pre-structure where self-assembly is predominantly influenced by the surface properties. There are no strict dimensional boundaries between these two pre-structure categories, as the extent of the topographical influence on self-assembly also depends on the thickness of the SA layer relative to the underlying relief surface. In general, however, when graphoepitaxial pre-structures are used, the thickness of the SA layer is usually less than or equal to the trench height of the underlying pre-structure. For chemical pre-structures, the thickness of the SA layer is greater than any trench height of the underlying topography.The hybrid precursor serves as a chemical precursor (the thickness of the SA layer is greater than the maximum sidewall height of the precursor), but has an underlying topography that influences and guides self-assembly. Furthermore, typical DSA is supported by an underlying precursor with a relatively uniform etch resistance. Unlike typical DSA precursors, hybrid precursors have significant etch contrast between the raised and depressed surfaces (e.g., the etch contrast between inorganic versus organic materials). For this reason, the term "hybrid" is used to describe the precursor.

[0015] Self-assembly can occur spontaneously upon formation of the SA layer or can be induced (for example, by thermal curing and / or curing of the SA layer with a solvent vapor).

[0016] A self-assembling block copolymer comprises at least two blocks that are immiscible with each other. Self-assembly of the block copolymer occurs by phase separation of the blocks to form a structure of separate solid-phase domains. For example, self-assembly of a diblock copolymer produces a domain structure comprising a first domain essentially containing a first block A of the diblock copolymer and a second domain essentially containing a second block B of the diblock copolymer. In this case, the first and second domains are connected by the covalent bond linking block A to block B of the block copolymer.

[0017] Here, a surface or interface is referred to as "neutral" for an SA material or "neutral-wetting" for an SA material if every region of the self-assembled SA material can wet the surface or interface (i.e., every region is in contact with the surface or interface after self-assembly). Otherwise, the surface or interface is considered "non-neutral" for the SA material. Raised surfaces of the pre-structure are neutral for the SA material. Depressed surfaces of the pre-structure can be neutral or non-neutral for the SA material, provided that the wetting properties of the depressed surfaces do not adversely affect the formation of perpendicularly oriented regions on the raised surfaces. The sidewalls of the pre-structure are preferably non-neutral surfaces.In one embodiment, the sidewalls of the pre-structure are in contact with a region of the self-assembled SA material. Depending on the final intended transfer structure, the regions formed over the respective recessed surfaces may have a perpendicular orientation, a parallel orientation, or a combination thereof with respect to the plane of the respective underlying recessed surfaces (or the plane of the lower layer of the substrate).

[0018] A surface is said to have a "preferential affinity for" or be "preferential for" a referenced region of a self-assembled SA material if the referenced region can wet the surface preferentially over another region of the self-assembled SA material. Otherwise, the interface surface is considered "non-preferential" for the regions of the SA material. The raised surfaces are not preferred for the regions of the self-assembled SA material. In one embodiment, the recessed surfaces and sidewalls have a preferential affinity for one of the regions of the self-assembled SA material.

[0019] In this document, any material of the hybrid prestructure that is in contact with the bottom surface of the SA layer is generally referred to as an "underlayer material." A layer that is in contact with the underside of the SA layer is referred to as an "underlayer" (UL). The underlayer material of the raised surfaces that is in contact with the SA layer is a first underlayer material. The underlayer material of the recessed surfaces that is in contact with the SA layer is a second underlayer material. The underlayer material of the sidewalls that is in contact with the SA layer can be a third underlayer material. The bulk material of a sublayer can be neutral or non-neutral wetting for the SA material. A non-neutral underlayer (UL) is a sublayer whose bulk material has non-neutral wetting properties for the regions of the self-assembled SA material.A non-neutral underlayer (UL) is a sublayer whose bulk material has neutral wetting properties for the regions of self-assembled SA material. Regardless of the wetting properties of the bulk material used to form a particular underlayer, the various processes used to fabricate the hybrid prestructures result in raised surfaces of the prestructure that are neutral wetting for the SA material, depressed surfaces that are neutral or non-neutral wetting for the SA material, and sidewalls that are preferentially non-neutral wetting for the SA material.The raised surfaces, recessed surfaces, and sidewalls of the pre-structure may contain residues of photoresist materials, filler materials, surface modification materials, and / or traces of materials, including small molecules, remaining on the raised surfaces after various processes. These surfaces may also contain residual SA material remaining on the raised surfaces, recessed surfaces, and sidewalls after stripping off an initially formed region structure of SA material.

[0020] Here, the atmospheric interface and / or cap layer in contact with the self-assembled SA layer supports a perpendicular alignment of the regions above the raised surfaces. Each of the lamellae above the raised surfaces is in contact with the respective raised surfaces and the atmosphere and / or cap layer.

[0021] In this document, the term "substrate" refers to an initial stack of layered materials used to form the pre-structure surfaces. The substrate may comprise one or more material layers arranged in a stack. The raised features of the top surface of the pre-structure may comprise one or more layers. As non-limiting examples, the substrate may include a silicon wafer or metal foil as a bottom layer, a hard mask layer, a dielectric layer, a metal oxide layer, a silicon oxide layer, and / or an anti-reflective coating (ARC). Generally, the substrate is the initial stack comprising a silicon wafer and any other layers used to fabricate a hybrid pre-structure.For clarity, the substrate in the figures described below is the initial stack on which a sublayer (e.g., neutral UL or non-neutral UL) is deposited as a first step in the fabrication of a hybrid pre-structure.

[0022] The term "disposed" refers to a layer that is in contact with the surface of another layer. "Disposing" or "applying" refers to the formation of a layer intended to be in contact with the surface of another layer, without limitation as to the method used, as long as the desired properties of the disposed or applied layer, such as uniformity and strength, are maintained.

[0023] The term “casting” refers to the formation of a layer of material by placing a solution of the material dissolved in a solvent on a surface and removing the solvent.

[0024] Statistical copolymers are indicated by "-co-" or "-r-" in the name. Block copolymers are indicated by "-b-" or "-block-" in the name. Alternating block copolymers are indicated by "-alt-" in the name.

[0025] In this document, the term "interface" refers to a contact boundary between two essentially immiscible phases. Each phase can be independently solid, liquid, or gaseous.

[0026] Here, self-assembly of the SA material preferably forms a domain structure comprising alternating domains containing chemically distinct components of the SA material (for example, each domain may comprise a block of a diblock copolymer). Preferably, the domains have a lamellar (i.e., thin plate or ribbon structure) or a cylindrical morphology. Each lamellar domain may have a plurality of lamellae. The lamellar or cylindrical domains may have a parallel or perpendicular orientation to the principal plane of the underlying surface or to the bottom layer of the substrate. A lamella has a parallel orientation if the principal plane of the lamella is oriented parallel to the principal plane of the underlying surface or to the bottom layer of the substrate.A lamella has a vertical orientation if the main plane of the lamella is oriented perpendicular to the main plane of the underlying surface or to the bottom layer of the substrate. A cylindrical region has a parallel orientation if the main cylinder axis is oriented parallel to the main plane of the underlying surface or to the bottom layer of the substrate. A cylindrical region has a vertical orientation if the cylinder axis is oriented perpendicular to the main plane of the underlying surface or to the bottom layer of the substrate.

[0027] A perpendicular alignment of the lamella region is desirable for the formation of high-resolution line structures by selectively etching a specific lamella region. In general, a parallel alignment is not desirable for the formation of a high-resolution line structure. The hybrid pre-structure enables the self-assembly of the SA layer to produce a region structure, wherein portions of the SA layer above the raised surfaces consist essentially of perpendicularly aligned lamellae arranged on the raised surfaces, and portions of the SA layer above the recessed surfaces have parallel and / or perpendicularly aligned lamellae. In one embodiment, the self-assembly of the SA layer creates perpendicularly aligned regions over the raised and recessed surfaces of the pre-structure with alignment over a wide range.

[0028] The examples below utilize the hybrid prestructure in the manner of a chemical prestructure (i.e., the thickness of the SA layer above the recessed surfaces is greater than the trench height (sidewall height) of the underlying topography). The SA layer is located at and above the raised and recessed surfaces of the prestructure and is in contact with the raised surfaces, recessed surfaces, and sidewalls. The topographic and surface properties of the hybrid prestructure guide the global alignment of the regions formed by self-assembly.

[0029] In summary, regarding the raised surfaces of the hybrid pre-structures, it can be said that the raised surfaces of the pre-structures are neutral for the SA material. The materials underlying the raised surfaces of the pre-structure have a higher etch resistance than the materials underlying the recessed surfaces of the pre-structure. The raised surfaces can independently have different widths W E have, where W Ethe length of the raised surface is perpendicular to the major axis of the pre-structure. The part of the self-assembled SA layer arranged on the raised surface essentially consists of regions (preferably lamellar regions) with a perpendicular orientation with respect to the major plane of the raised surface or to the bottom layer of the substrate. Each of the regions is in contact with the raised surface and the atmospheric interface (and / or a cap layer) on top of the SA layer. Furthermore, the regions are aligned with the major axis of the pre-structure.

[0030] In summary, regarding the recessed surfaces, the recessed surfaces of the hybrid pre-structure can be neutral or non-neutral for the SA material under the above assumption. In one embodiment, the recessed surfaces have a preferential affinity for a region of the self-assembled SA material. The materials underlying the recessed surfaces of the pre-structure have a higher etch resistance than the materials underlying the raised surfaces of the pre-structure. The recessed surfaces can independently have different widths W R have. W Ris the length of the recessed surface perpendicular to the major axis of the pre-structure. The part of the self-assembled SA layer disposed on the recessed surfaces may have regions (preferably lamellar regions) with a parallel and / or perpendicular orientation with respect to the major plane of the recessed surface or to the bottom layer of the substrate. One or more of the regions may be in contact with the recessed surfaces and the atmosphere interface (and / or cap layer) at the top of the SA layer. The part of the self-assembled SA layer disposed on the recessed surfaces may contain zero or more parallel regions, depending on the width and surface properties of the recessed surfaces, the SA layer thickness, and the surface properties of the sidewalls of the pre-structure.

[0031] In summary, regarding the sidewalls of the hybrid pre-structure, it can be said that the sidewalls can preferably be neutral or non-neutral for the SA material under the above assumption. The sidewalls have a height H N of at least 0.1 Lo. In one embodiment, the sidewalls have a preferred affinity for a region of the self-assembled SA material. In another embodiment, the sidewalls contact a post-self-assembly region, and the region has a perpendicular orientation relative to the respective underlying recessed surfaces.

[0032] With respect to an adjacent pair of raised and depressed surfaces, the sum of the widths can have a value approximately equal to an integer multiple of Lo, the periodicity (characteristic pitch) of the domain structure. Thus, W E + W Rfor adjacent raised and depressed surfaces approximately equal to nLo (n times L O ), where n is an integer from 2 to about 30.

[0033] The combination of surface properties, in-plane geometry, and topography (raised surfaces, depressed surfaces, and sidewalls) guide the self-assembly of the SA material across the hybrid prestructure. The preferential affinity of the sidewalls to a specific region can promote the alignment of the regions along the sidewalls. The neutral raised surfaces support the perpendicular alignment of the regions in contact with the raised surfaces. The global alignment of the regions is achieved by maintaining the in-plane dimensionality of the prestructure across the principal axis direction (i.e., W E + W R= nLo, where n is a positive integer for adjacent raised and depressed surfaces) in combination with the topography and surface properties of the pre-structure surfaces.

[0034] Fig. Figure 2B, described in more detail below, illustrates an embodiment in which a self-assembled SA layer includes vertically aligned lamellae over raised and depressed surfaces. The vertical lamellae over the raised surfaces are in contact with the raised surfaces and the atmosphere interface at the top surface of the SA layer. The vertically aligned lamellae over the depressed surfaces are arranged on a thin layer of one region (parallel region) in contact with the depressed surfaces. In this case, each of the regions of the self-assembled SA material over the depressed surfaces is in contact with the atmosphere interface, but only one region is in contact with the depressed surface.Viewed from top to bottom, the vertically aligned domain structure may appear as a uniform unidirectional lamellar domain structure extending through the SA layer (for example, as a large-scale linear array structure).

[0035] As another example, Fig. 8 vertical slats formed over the raised surfaces and adjacent to the side walls, and parallel slats formed over the central region of the recessed surfaces (W E +W R = 8 Lo for adjacent raised and depressed surfaces, SEM images of W E ~ 2 Lo, 3 Lo, and 4 Lo). Each area of ​​lamellar structure above the raised and depressed surfaces shows a long-range alignment.

[0036] The following discussion focuses on lamellar domain structures, but also applies to cylindrical domain structures. For illustrative purposes, the SA material is a self-assembling diblock copolymer. It is understood that the layer diagrams in the figures and schematics below are neither to scale nor intended to limit the possible structures that can be created using the processes described below. The diagrams are for illustrative purposes only.

[0037] Without being bound to a theory, this is Fig. Figure 1A illustrates a schematic representation of parallel-aligned lamellar domains of a self-assembled diblock copolymer. In this case, the principal plane of each lamellar domain is parallel to the plane of the sublayer surface.

[0038] Scheme 1 shows the arrangement of blocks A and B of a diblock copolymer after self-assembly of the diblock copolymer on a sublayer with a non-neutral surface, which is preferred for block A. In this example, the atmospheric interface is also preferred for block A. The first lamellar region comprises block A and the second lamellar region comprises block B. The periodicity Lo of the regions is given by 1.0 Lo (once Lo, Lo = 1.0 Lo). For lamellar regions, the thickness of a lamellar region is approximately 0.5 Lo. The individual diblock copolymer macromolecules, region boundaries, and 0.5 Lo are also given. In this example, the sublayer surface is in contact with block A of the self-assembled diblock copolymer.It is understood that within a given lamellar region (e.g., the second lamellar region of Scheme 1), blocks of different polymer macromolecules (e.g., B blocks) can be arranged continuously (shown) and / or interwoven (not shown). Each block can have a backbone that can be rigid, non-rigid, or have intermediate rigidity. Each block can exhibit any suitable coiling, rotation, and / or bending capability.

[0039] Without being bound to a theory, this is Fig. Figure 1B illustrates Scheme 2, a schematic representation of vertically aligned lamellar domains of a self-assembled block copolymer on a sublayer with a neutral surface. The principal plane of each lamellar domain is perpendicular to the plane of the sublayer (or the bottom layer of the substrate, not shown). In this example, each lamellar domain is in contact with the atmosphere interface (and / or the top layer interface, not shown) and the sublayer surface. The bulk periodicity, 1.0 Lo, is indicated, as is 0.5 Lo. In this example, the sublayer surface is in contact with both block A and block B of the self-assembled diblock copolymer.

[0040] The atmospheric interface is typically non-neutrally wetting for a block copolymer for self-assembly. Nevertheless, in some cases, the hybrid prestructures of the invention can provide a perpendicular alignment of lamellar regions over the raised surfaces and optionally recessed surfaces without the use of a neutral capping layer.

[0041] The lamellar domain structures may have a periodicity Lo in the range of about 4 nm to about 80 nm, which is useful for fabricating line features each having a half-pitch of about 2 nm to about 40 nm, in about 5 nm to about 30 nm. Hybrid prestructures

[0042] The hybrid prestructures comprise two or more layers. The hybrid prestructures have a topographical upper surface that includes raised features and depressed features. The raised features comprise raised surfaces. The depressed features comprise depressed surfaces defined by sidewalls. The raised surfaces are neutral for a particular SA material. The depressed surfaces can be neutral or non-neutral within the above assumption. The sidewalls are preferably non-neutral for the SA material. The combination of raised surfaces, depressed surfaces, and sidewalls guides self-assembly.

[0043] Fig. 1C is a cross-sectional diagram of a non-limiting example of a three-layer hybrid precursor 10 comprising a first layer 15 (e.g., a silicon wafer), a second layer 16 (e.g., a transfer layer), and a topographical layer 17 (e.g., an inorganic hard mask layer). The topographical layer 17 comprises raised features 11 comprising an etch-resistant material 19 interspersed with and adjacent to recessed features 12 (e.g., trenches). Raised features 11 comprise raised surfaces 13 that are neutral to a particular SA material for self-assembly. Raised surfaces 13 support perpendicular alignment of the self-assembled regions of the particular SA material. The material beneath the raised surfaces 13 also has a higher etch resistance in an etching process compared to the material beneath the recessed surfaces 14. The etching process may be a wet and / or dry etching process.Raised surfaces 11 may also have different widths defined by W. E1 , W E2 and W E3 which is the length of a certain raised surface 11 in a direction perpendicular to the main axis 19 ( Fig. 1D). Raised features 11 may also include one or more material layers (not shown), which may be organic, inorganic, or combinations thereof.

[0044] Recessed features 12 have recessed surfaces 14 defined by side walls 18 of height H Nare limited. Recessed surfaces 14 may be neutral or non-neutral for a particular SA material, subject to the stated proviso (i.e., that the surface properties of the recessed surfaces 12 do not adversely affect the formation of perpendicularly oriented regions above raised surfaces 13). Sidewalls 18 are preferably non-neutral to the SA material. In the case of a strong affinity between a region and recessed surfaces 14, the recessed surfaces 14 may be in contact substantially or exclusively with one of the regions of the SA material. In this case, the recessed surfaces 14 may promote a parallel alignment of the preferred region in contact with the recessed surfaces 14 (shown).In some cases, as illustrated below, the fins of each of the regions in contact with the atmosphere interface (and / or the cap layer, not shown) above the recessed surfaces may be aligned perpendicular to the underlying recessed surfaces. The sidewalls 18 may play a significant role in guiding the alignment of the regions. A strong affinity between the sidewalls and a region may enhance the alignment of the regions across the raised and recessed surfaces. The material beneath the recessed surfaces 14 also has lower etch resistance in an etch process compared to the material beneath the raised surfaces 13. Recessed features 12 may also have different widths, indicated by W. R1 and W R2 which is the length of a particular recessed surface 13 in a direction perpendicular to the main axis A' ( Fig. 1B).

[0045] The sum of the widths of a pair of adjacent raised (W Ei ) and deeper (W Ri ) surfaces is an integral multiple of the characteristic pitch Lo of the SA material (e.g., block copolymer). That is, W Ei +W Ri = n×Lo (e.g., n times Lo, or nLo), where n is an integer having a value of 2 or higher, from 2 to about 30, from 2 to about 20, and more specifically from 2 to about 10. The subscript i is a number indicating an index value for indicating proximity. At least one raised surface 13 and at least one depressed surface 14 have respective widths greater than about 2.0 Lo. The sidewall height H N can be greater than or equal to approximately 0.1 Lo. In particular, H N about 0.1 Lo to about 2.0 Lo, more specifically about 0.2 Lo to about 2.0 Lo.

[0046] Fig. Figure 1D is a top-down view of a hybrid pre-structure 10 having a major geometric axis A', raised features 11 with raised surfaces 13, depressed features 12 with depressed surfaces 14, and widths W E1 , W E2 , W E3 , W R1 and W R2 .has.

[0047] The upper surface of the hybrid pre-structure may have two or more areas that are in the value of W R , W E , W R +W E or combinations thereof, provided that W R + W E is an integer multiple of Lo for adjacent raised and depressed surfaces in each of the two or more regions. In one embodiment, the upper surface of the hybrid pre-structure has two or more regions along the major axis of the hybrid pre-structure, and the two or more regions have different values ​​of W R +W Efor adjacent raised and depressed surfaces.

[0048] Fig. 2A through 2D are cross-sectional layer diagrams illustrating an exemplary non-limiting process for fabricating a transfer structure with customized features using a hybrid pre-structure. A solution comprising an SA material and a solvent is applied to the hybrid pre-structure 10 of Fig. 1C (for example, by spin coating), followed by removal of the solvent, formation of structure 20 ( Fig. 2A). Structure 20 includes SA layer 21, which includes SA material disposed on raised surfaces 13 of raised features 11 and on recessed surfaces 14 of recessed features 12. Raised surfaces 13 are neutral-wetting for the regions of self-assembled SA material. In this example, recessed surfaces 14 and sidewalls 18 are non-neutral-wetting for the regions of self-assembled SA material. Sidewalls 18 have a height H n . Enabling or inducing self-organization of SA layer 21 leads to structure 30 ( Fig. 2B). Structure 30 has a self-assembled lamellar domain structure 31 of the self-assembled SA material, which extends over raised surfaces 13 and depressed surfaces 14. W Ei +W Ri= nLo (n times Lo) for a pair of adjacent raised and depressed surfaces, where n is an integer from 2 to about 30 and i is an index indicating the neighborhood.

[0049] Optionally, the domain structure 31 can be exposed from the structure 30 (not shown) to form a modified hybrid pre-structure. Applying a second layer of SA material to the top surface of the modified hybrid pre-structure, followed by self-assembly of the second layer, can form a second lamellar domain structure with vertically aligned domains above the raised surfaces. The second lamellar domain structure can have fewer defects associated with the self-assembled domains compared to the initial lamellar domain structure 31.

[0050] The lamellar region structure 31 alternates between the first region 32 and the second region 33. Each of the first region 32 and the second region 33 comprises a plurality of lamellae. The first region 32 and the second region 33 comprise chemically different components of the SA material (e.g., blocks of a block copolymer). Raised surfaces 13 are in contact with the first region 32 and the second region 33. The lamellae of each region that are in contact with the raised surfaces 13 are oriented perpendicular to the principal plane of the raised surfaces 13 (or to the first layer 15, which is a bottom layer of the substrate). In this example, the lamellae of each region that are in contact with the atmospheric interface 34 above the depressed surfaces 14 are oriented perpendicular to the respective underlying depressed surfaces 14.The vertically aligned lamellae above the raised surfaces 13 and the depressed surfaces 14 are aligned along the major axis (not shown) of the hybrid prestructure. The characteristic pitch Lo of the self-assembled SA material is also indicated in structure 30. In this example, the depressed surfaces 14 and the sidewalls 18 substantially or exclusively contact the material of the first region 32 due to a strong preferential affinity of the depressed surfaces 14 and the sidewalls 18 to the first region 22 (shown). Therefore, the first region 32 can take the form of a thin wetting layer on the depressed surfaces 14, as shown in structure 30. In this example, the second region 33 has substantially no contact with the depressed surfaces 14. Sidewalls 18 assist in the alignment of the lamellar region structure 31 along the major axis of the prestructure.

[0051] One of the regions has a higher etch resistance in a particular etch process, which may be a wet and / or a dry etch process. In this example, the first region 32 (for example, regions comprising a poly(styrene) (PS) block of BCP) has a higher etch resistance compared to the second region 33 (regions comprising a poly(methyl methacrylate) (PMMA) block of PCB). Therefore, the fins of the second region 33 can be selectively removed, leaving the fins of the first region 32, as shown in structure 40 ( Fig. 2C). Structure 40 includes an etched region structure 41 disposed on the second layer 16. The etched region structure 41 includes lamellae of the first region 32 disposed on the raised surfaces 43 and on the recessed surfaces 45. It is understood that the recessed surfaces 45 may have a thin residual layer of the first region 32 disposed thereon (not shown). Depending on the etching conditions, the raised features 44 may have the same or different widths, as indicated by W' E1 , W' E2 and W' E3 compared to the raised features 11. Likewise, the recessed features 46 may have the same or different widths, as indicated by W' R1 and W' R2in comparison to the recessed features 12. The recessed surfaces 45 may be upper surfaces of the second layer 16. The etched region structure 41 may then be transferred using a second etching process to the more highly etch-resistant materials underlying the raised surfaces 43, thereby forming the structure 50a ( Fig. 2D). The structure 50a includes a transfer structure 51a having topographical transfer features 55a arranged on the second layer 16. In this example, the topographical transfer features 55a comprise etch-resistant material 19. The transfer structure 51a may also include residual portions of lamellae of the first region 32 (not shown).

[0052] In this example, the transfer structure 51a has three customized features. Other customizable features are possible. A first customized feature is a first arrangement 52a comprising three transfer features 55a formed by etching the relief structures 41 over the raised feature 44 of width W'. E1 Another adapted feature is a second arrangement 53a comprising two transfer features 55a formed by etching relief structures 41 over the raised feature 44 of width W' E2 Another adapted feature is a third arrangement 54a comprising four transfer features 55a formed by etching relief structures 41 over the raised feature 44 of width W' E3 The first field 52a has a width W'' E1 which is smaller than W' E1 . The second field 53a has a width W'' E2 which is smaller than W' E2. The third field 54a has a width W'' E3 which is smaller than W' E3 . The first field 56a is separated from the second field 53a by a spatial area 56a with a width W'' R1 separated, which in this example is greater than W' R1 . A second field 53a is separated from the third field 54a by a spatial area 57a with a width W'' R2 separated, which in this example is greater than W' R2 .

[0053] Optionally, the transfer structure 51a may be selectively transferred to one or more underlying layers of the substrate using a third etching process, thereby forming the structure 50b ( Fig. 2E). In this example, structure 50b includes a second transfer structure 51b having topographical features 55b (e.g., pillars) disposed on first layer 15. In this example, topographical features 55b (shown as pillars) include residual etch-resistant material 19 and material of second layer 16.

[0054] In this example, the transmission structure 51b has three adapted features. Other adaptable features are possible. A first adapted feature is a first arrangement 52b comprising three topographical features 55b that, by transmitting, form the first field 52a of width W''. E1 in the second layer 16. Another adapted feature is a second field 53b, which has two topographical features 55b, which are formed by transferring the second field 53a of width W'' E2formed in the second layer 16. Another adapted feature is a third field 54b, which has four topographical features 55b, which are formed by transferring the third field 54a of width W'' E3 onto the second layer 16. The first field 52b has a width W'''' E1 , which is essentially equal to W' E1 The second field 53b has a width W''' E2 , which is essentially equal to W'' E2 can be equal. The third field 54b has a width W''' E3 , which is essentially equal to W'' E3 The first field 52b is separated from the second field 53b by a spatial area 56b with a width W''' R1 separated, which is for example larger than W'' R1 . The second field 53b is separated from the third field 54b by a spatial area 57b with a width W''' R2 separated, which is essentially with W'' R2 can be the same. Manufacturing processes for hybrid prestructures

[0055] Various methods for producing hybrid pre-structures are described below. Each of the methods uses a three-layer substrate 60, which is Fig. 3A. The substrate 60 comprises a first layer 61 (e.g., Si wafer) comprising a first material 65 (e.g., silicon, metal), also referred to as the bottom layer of the substrate, a second layer 62 (e.g., transfer layer, TL) comprising a second material 66 (e.g., silicon nitride (SiN x ), carbon film, spin-on carbon), and a third layer 63 (e.g., a hard mask, HM) comprising third material 67 (e.g., silicon oxide, metal oxide, an anti-reflective coating such as SiARC and / or TiARC). The third layer 63 has a surface 64. 1. Procedure

[0056] Fig. 3A to 3E illustrate Method 1 (basic method) of forming a hybrid pre-structure using a pre-formed multilayer substrate 60. A solution of a neutralizing material (a polymer that is neutral-wetting for a particular SA material, such as a block copolymer) is applied to the surface 64, followed by removal of the solvent, forming the structure 70 ( Fig. 3B). The structure 70 includes a neutral underlayer 71. The neutral underlayer 71 may be cross-linked, covalently bonded to the third layer 63, or otherwise immobilized. The neutral layer 71 has a neutral surface 72 comprising neutral material 73. The neutral surface 72 is neutral-wetting for the areas of the particular SA material. The topographic photoresist pattern is formed on the neutral surface 72 using known lithographic techniques, forming the structure 80 ( Fig. 3C). In this example, the neutral properties of surface 72 are retained after forming the photoresist pattern, transferring the photoresist pattern, and stripping the photoresist pattern.

[0057] The formation of the photoresist structure may comprise i) disposing a photoresist on a surface 72 (for example, by spin coating) and removing any solvents to form a photoresist layer, ii) optionally baking the photoresist layer, iii) exposing the cured or uncured photoresist layer to radiation (for example, E-beam, extreme UV (EUV), deep ultraviolet (DUV)), iv) optionally baking the exposed photoresist layer, v) developing the baked or unbaked exposed photoresist layer to form a positive or negative photoresist, and iv) optionally baking the photoresist structure.

[0058] Structure 80 includes a first topographical structure 81 disposed on neutral surface 72. First topographical structure 81 may be a positive structure or a negative structure. First topographical structure 81 includes topographical photoresist features 82 comprising photoresist material 85 disposed on neutral surface 72. Photoresist features 82 may have various widths (not shown). Photoresist features 82 are separated by trenches 83 and bottom surfaces 86 comprising neutral material 73. Trenches 83 may have various widths (not shown). Trenches 83 are bounded by sidewalls 84 comprising photoresist material 85 and bottom surfaces 86.

[0059] The structure 80 is then treated with one or more wet and / or dry etchings and optionally oxygen etchings, thereby producing the structure 90 ( Fig. 3D). In this example, a third material 67 of the third layer 63 and neutral material 73 of the neutral layer 71 were removed from the bottom surfaces 86 of the trenches 83 ( Fig. 3C), which shows the deepened features 93 of Fig. 3D. A portion of the photoresist features 82 may also be removed by the etching process (shown). The structure 90 includes a second topographical structure 91 having raised features 92 separated by depressed features 93. The second topographical structure 91 includes a photoresist layer 96, a neutral layer 95, and a third layer portion 94. The depressed features 93 include depressed surfaces 97 that are non-neutral to the SA material.

[0060] Removing the remaining photoresist material 85 from the structure 90 forms the structure 100 ( Fig. 3E), a hybrid pre-structure for self-assembly. The structure 100 includes a patterned layer 101 (top surface of the hybrid pre-structure) having raised features 102, depressed features 103, and sidewalls 108 connecting the raised features 102 to the depressed features 103. The patterned layer 101 includes raised features 102 including a third layer 104 including third material 67 and a neutral layer 105 including neutral material 73. The raised features 102 include raised surfaces 106 including neutral material 73 and any remaining photoresist 85. The raised surfaces 106 are neutral-wetting for the regions of SA material formed by self-assembly. In this example, the neutral properties of surface 72 are retained after forming the photoresist pattern, transferring the photoresist pattern, and stripping the photoresist pattern.Recessed features 103 have recessed surfaces 107 defined by side walls 108 of height H. N limited second material 66. In the present example, the recessed surfaces 107 and sidewalls 108 have the desired surface properties for self-assembly of the SA material without further modification. The recessed surfaces 107 can be neutral or non-neutral to the SA material under the conditions outlined above. Sidewalls 108 are preferably non-neutral to the SA material. Raised features 102 can have various widths defined by W E1 , W E2 and W E3 Recessed features 103 can have different widths, which are defined by W R1 and W R2 be displayed. W Ei +W Ri= nLo for a pair of adjacent raised and depressed surfaces, where n is an integer from 2 to about 30 and i is an index indicating the neighborhood. 2. Procedure

[0061] Fig. 4A to 4C illustrate the second process (filling process) of forming a hybrid pre-structure starting at structure 110 ( Fig. 4A). Structure 110 corresponds to the structure 90 of Fig. 3D with the restriction that the bottom surfaces 111 of the trenches 112 of Fig. 4A do not have desired surface properties for guided self-assembly of a particular SA material.

[0062] In this example, after an optional hardening of the topographical structure 113 (for example, by firing the second topographical structure 113 at a suitable elevated temperature), trenches 112 of the topographical structure 113 are partially filled with a material to a level below the top surface of the neutral layer 95, thereby forming the structure 120 ( Fig. 4B). The structure 120 includes a patterned layer 121 having raised features 125 with sidewalls 127 and trenches 123. The structure 120 also includes the fill layer 122 having fill material 124. The trenches 123 have bottom surfaces 126 having fill material 124. In this example, the patterned layer 121 includes the photoresist layer 96 and a portion of the neutral layer 95. Raised features 125 include photoresist material 85 and neutral material 73. Sidewalls 127 may interact with the filled materials 124 to form a thin layer of fill material 124 on the sidewalls 127 (not shown).

[0063] Removing the photoresist material 85 from the structure 120 forms the structure 130 ( Fig. 4C), a hybrid pre-structure for self-assembly. The structure 130 comprises a patterned layer 131 having raised features 132, recessed features 133, and sidewalls 135 connecting the raised features 132 to the recessed features 133. In this example, the raised features 132 comprise a portion of a neutral layer 95 comprising neutral material 73 and any remaining photoresist 85. Recessed features 133 have recessed surfaces 136 comprising fill material 124 defined by sidewalls 135 of height H Nare limited. Sidewalls 135 may comprise neutral material 73 (shown) and / or a thin coating of fill material 124 (not shown). Raised surfaces 134, comprising neutral material 73 and any remaining photoresist material 85, are neutral to the SA material. In the present example, recessed surfaces 136 and sidewalls 135 have the desired surface properties for self-assembly of the SA material without further modification. Recessed surfaces 136 may be neutral or non-neutral to the SA material under the conditions set forth above. Sidewalls 135 are preferably non-neutral to the SA material. The material beneath raised surfaces 134 has a higher etch resistance than the material beneath recessed surfaces 136 in a given etch process.In one embodiment, sidewalls 135 and recessed surfaces 136 have a preferred affinity to a region of the SA material. Raised features 132 may have various widths defined by W. E1 , W E2 and W E3 Recessed features 133 can have different widths, which are defined by W R1 and W R2 be displayed. W Ei +W Ri = nLo for a pair of adjacent raised and depressed surfaces, where n is an integer from 2 to about 30 and i is an index indicating the neighborhood. 3, Procedure

[0064] Fig. 5A to 5B illustrate the third method (surface modification method) of forming a hybrid pre-structure from the structure 140 ( Fig. 5 A), which, apart from the following exceptions, are similar to the structure 100 of Fig. 3E. The structure 140 comprises a patterned layer 141 having raised features 144 and depressed features 143 comprising layer 144 and layer 145. Layer 145 comprises material 147. The raised features 144 have raised surfaces 146. Depressed features 143 have depressed surfaces 142 defined by sidewalls 148 of height H'. Raised surfaces 146 are neutral for a particular SA material. The depressed surfaces 142 do not have surface properties suitable for guided self-assembly of the particular SA material. The sidewalls 148 may or may not have suitable surface properties for self-assembly of a particular SA material.

[0065] The structure 140 is treated with a non-neutral surface modification material, whereby a structure 150 ( Fig. 5B) is formed as a hybrid pre-structure. The structure 150 includes a patterned layer 151 having raised features 152 and depressed features 153. The patterned layer 151 includes a third layer 154 and a neutral layer 155. The structure 150 also includes a surface-modified second layer 157. The modified second layer 157 includes modified depressed surfaces 159 of the depressed features 153. The surface modification may change the surface properties of the sidewalls 148 (not shown). The raised surfaces 156 and sidewalls 158 may include surface modification material (not shown) in amounts that do not adversely affect the self-assembly of the particular SA material to produce perpendicularly oriented lamellae on raised surfaces 156. Thus, raised surfaces 156 are neutral for a particular SA material after surface modification.Modified recessed surfaces 159 and sidewalls 158 are non-neutral to the SA material after surface modification. The material beneath the raised surfaces 156 exhibits a higher etch resistance in a given etch process than the material beneath the modified recessed surfaces 159.

[0066] The structured layer 151 may have a substantially similar topology and dimensions as the structured layer 141 of Fig. 5A (not shown). This means that the surface modification can essentially leave the dimensions of the structured layer 141 unchanged. Typically, the surface modification leads to a difference of 5 nm in the sidewall height H'. The height H N from Fig. 5B can be substantially equal to the height H' of Fig. 5A. The widths W E1 , W E2 and W E3 of the increased features 152 of Fig. 5B may be the same or substantially the same as W' E1 , W' E2 and W' E3 of the increased features 102 of Fig. 5A. The widths W R1 and W R2 of the in-depth features 153 of Fig. 5B may be the same or substantially the same as W' R1 , and W' R2 of the deepened features 143 of Fig. 5A. In Fig. 5B applies W Ei +W Ri = nLo for a pair of adjacent raised and depressed surfaces, where n is an integer from 2 to about 30 and i is an index indicating the neighborhood. The height H N is between 0.1 Lo to about 2.0 Lo.

[0067] The surface modification may be performed, for example, by applying a dilute solution of a brush polymer to structure 140 under conditions that can reduce the deposition of the brush polymer on the raised surfaces 106, followed by firing. 4. Procedure

[0068] Fig. 6A to 6B illustrate the fourth method (double modification method) for forming a hybrid pre-structure from the structure 160 ( Fig. 6A), which, with the following exceptions, are part of the structure 130 of Fig. 4C. The structure 160 comprises a patterned layer 161 having raised features 162 and depressed features 163. The raised features 162 comprise a portion of the top layer 166 comprising top layer material 165. Depressed features 166 comprising filler material 124 are defined by sidewalls 167 of height H'. Raised features 162 have raised surfaces 164, which, in this example, do not have properties suitable for self-assembly of a particular SA material. Depressed surfaces 136 and sidewalls 167 have suitable surface properties for self-assembly of a particular SA material.

[0069] Raised surfaces 164 are surfaces modified with a neutral material, creating structure 170 ( Fig. 6B), a hybrid pre-structure. The structure 170 includes a patterned layer 171 having raised features 172 and depressed features 173. The patterned layer 171 also includes a filler layer 122 having filler material 124, a remaining third layer 94 having third material 67, and a surface-modified cap layer 174. Raised features 172 have raised surfaces 175 that are neutral to a particular SA material. Depressed features 173 have depressed surfaces 176 defined by sidewalls 177. Depressed surfaces 176 and sidewalls 177 have suitable surface properties for self-assembly of the particular SA material (i.e., their surface properties are not negatively affected by the surface modifier).The recessed surfaces 176 and sidewalls 177 may include surface modification material (not shown) in amounts that do not adversely affect the self-assembly of a particular SA material to create vertically aligned lamellae on raised surfaces 175. The material beneath the modified raised surfaces 175 exhibits a higher etch resistance than the material beneath the recessed surfaces 176 in a given etch process.

[0070] The structured layer 171 may have a substantially similar topology and dimensions as the structured layer 161 of Fig. 6A. That is, the surface modification of the raised features 162 does not necessarily fundamentally change the dimensions of the structured layer 161, but rather the surface properties of the raised features 162. The height H' of Fig. 6A can be substantially equal to the height H N from Fig. 6B. The widths W E1 , W E2 and W E3 of the increased features 172 of Fig. 6B may be equal or substantially equal to W' E1 , W' E2 and W' E3 of the increased features 162 of Fig. 6A. Likewise, the widths W R1 and W R2 of the deepened features 173 of Fig. 6B equal to or substantially equal to W' R1 , and W' R2 of the deepened features 163 of Fig. 6A. In Fig. 6B W Ei +W Ri = nLo for a pair of adjacent raised and depressed surfaces, where n is an integer from 2 to about 30 and i is an index indicating the neighborhood. The side walls 177 have the height H N which ranges from 0.1 Lo to about 2.0 Lo. 5. Procedure

[0071] Fig. 7A to 7B illustrate the fifth method (photoresist modification method) of forming a hybrid pre-structure from the structure 180 ( Fig. 7A), which, apart from the following differences in structure 80 of Fig. 3C. The structure 180 comprises a topographical photoresist structure 181 having raised features 182 and depressed features 183. Raised features 182 comprise photoresist material 187 and have sidewalls 184 of height H'. The photoresist structure 181 is disposed on a non-neutral layer 185 comprising non-neutral material 186. The depressed features 183 have depressed surfaces 188 comprising non-neutral material 186 and defined by sidewalls 184. The depressed surfaces 188 and the sidewalls 184 have suitable surface properties for self-assembly of a particular SA material. The raised surfaces 189 do not have suitable surface properties for self-assembly of a particular SA material.

[0072] The raised surfaces 189 are surface-modified with a neutral material (e.g., by treating raised surfaces 189 with a brush polymer), resulting in structure 190 ( Fig. 7B), a hybrid pre-structure. The structure 190 includes a modified photoresist structure 191 having raised features 192 and depressed features 193. Raised features 192 include raised surfaces 199 that are neutral for a particular SA material. The depressed features 193 have depressed surfaces 198 defined by sidewalls 194. Depressed surfaces 198 and sidewalls 194 have suitable surface properties for self-assembly of the particular SA material (i.e., the surface properties of the depressed surfaces 198 and sidewalls 194 are not adversely affected by the surface modifier). The depressed surfaces 198 and sidewalls 194 may include surface modifier material (not shown) in amounts that do not adversely affect the self-assembly of a particular SA material to produce perpendicularly aligned lamellae on raised surfaces 199.The material under the raised surfaces 199 has a higher etch resistance than the material under the depressed surfaces 198 in a given etching process.

[0073] The modified photoresist layer 191 may have a substantially similar topology and dimensions to a photoresist structure 181 of Fig. 7A. That is, the surface modification of the raised features 182 does not necessarily fundamentally change the dimensions of the photoresist structure 181, but rather the surface properties of the raised features 182. The height H' of Fig. 7A can be substantially equal to the height H N from Fig. 7B. The widths W E1 , W E2 and W E3 of the modified elevated features 192 of Fig. 7B may be equal or substantially equal to the widths W' E1 , W' E2 and W' E3 of the increased features 182 of Fig. 7A. Likewise, the widths W R1and W R2 the modified recessed features 193 of Fig. 7B equal or substantially equal to W' R1 , and W' R2 of the deepened features 183 of Fig. 7A. In Fig. 7B W Ei +W Ri = nLo for a pair of adjacent raised and depressed surfaces, where n is an integer from 3 to about 30 and i is an index indicating the neighborhood. The side walls 194 have the height H N which ranges from 0.1 Lo to about 2.0 Lo. Underlayer materials

[0074] In this document, an underlayer is any layer that is in contact with the bottom of the SA layer. Underlayers include neutral layers, non-neutral layers, fill layers, surface-modified photoresist layers, substrate layers, surface-modified substrate layers, and etched substrate layers. The underlayer material is any material that is in contact with the bottom of the SA layer. The underlayer material can comprise organic material, inorganic material, organometallic material, or a combination of the foregoing materials. The underlayer material can be neutral or non-neutral for a particular SA material, with the following restrictions: Underlayer materials from raised surfaces of the pre-structure are neutral for the particular SA material.Underlayer materials of the recessed surfaces and sidewalls of the pre-pattern can be neutral or non-neutral to the SA material independently, subject to the above assumption. Sidewall surfaces, which are typically preferred for a region, also serve as part of the guiding features and can be modified by the selected underlayer materials during the pre-pattern fabrication processes. The choice of underlayer materials for the raised and recessed surfaces depends on the choice of SA materials, the pre-pattern fabrication process, including the photoresist materials for the lithography and plasma etching processes, and the pre-pattern dimensions. Therefore, no attempt is made to separately categorize the neutral and non-neutral underlayer materials for forming a hybrid pre-pattern.The following is a general discussion of the underlayer materials for potential use in forming the above-described neutral layers, filler layers, non-neutral layers, and various modified surfaces. It should be understood that the surfaces of the substrate layers and the surfaces of the etched substrate layers may potentially be used for the raised and depressed surfaces of the hybrid pre-structure without further surface modification. Alternatively, the surfaces of the substrate layer and the etched substrate layers may be surface-modified, with an underlayer material having suitable wetting properties relative to the SA material.

[0075] Backsheet materials include polymers containing a hydroxyl group. These include hydroxyl-terminated polymers (e.g., hydroxyl-terminated poly(styrene-co-methyl methacrylate) and blends of hydroxyl-terminated poly(styrene), hydroxyl-terminated poly(methyl methacrylate), and poly(styrene-b-methyl methacrylate)), hydroxyl-functionalized polymers (e.g., poly(styrene-co-methyl methacrylate-co-2-hydroxyethyl methacrylate)). Other backsheet materials include materials containing reactive groups, such as those derived from epoxydicyclopentadiene methacrylate, glycidyl methacrylate, or vinyl cinnamates.Exemplary materials include reactive groups such as poly(styrene-co-epoxydicyclopentadiene methacrylate), poly(styrene-co-methyl methacrylate-co-epoxydicyclopentadiene methacrylate), poly(styrene-co-methyl methacrylate-co-glycidyl methacrylate), poly(styrene-co-methyl methacrylate-co-vinyl cinnamate), poly(styrene-co-methyl methacrylate-co-vinyl benzocyclobutane), and poly(alpha-methyl styrene-co-methyl methacrylate). The reactive polymers can react as a result of thermal or photothermal treatment, either alone or in conjunction with another crosslinking agent. In particular, catalytic species, such as strongly acidic species, can be used to facilitate the reaction. The strongly acidic species can be incorporated directly into the underlayer material or the solution comprising the underlayer material.Alternatively, a thermal acid generator or a photoacid generator molecule can be used to form an acidic species as a result of thermal or photochemical treatment. The above materials are particularly suitable for use with an SA material comprising poly(styrene-b-methyl methacrylate) block copolymers. Poly(methylglutarimide) (PMGI) can be an underlayer material for an SA material comprising a poly(styrene-b-ethylene oxide) block copolymer.

[0076] Other non-limiting examples of underlayer materials include materials used in ARC layers, which may include homopolymers and copolymers selected from the group consisting of polybisphenols, polysulfones, polycarbonates, polyhydroquinones, polyphthalates, polybenzoates, polyphenyl ethers, polyhydroquinone alkylates, polycarbamates, polymalonates, and mixtures thereof. These units are typically functionalized to optimize the required physical properties of the polymer (e.g., optical properties, surface energy, etch resistance). The polymer components also typically contain a variety of reactive sites distributed along the polymer for reaction with a crosslinking component.

[0077] Zu spezifischeren, in ARC-Schichten verwendeten Materialien gehören Poly(4,4'-methylenbisphenol-co-epichlorhydrin), Poly(4,4'-ethylidenbisphenol-co-epichlorhydrin), Poly(4,4'-isopropylidenbisphenol-co-epichlorhydrin), Poly(4,4'-isopropylidenbis[2-methylphenol]-co-epichlorhydrin), Poly(4,4'-isopropylidenbis[2,6-dimethylphenol]-co-epichlorhydrin), Poly(4,4'-cyclohexylidenbisphenol-co-epichlorhydrin), Poly(4,4'-[1-phenylethyliden]bisphenol-co-epichlorhydrin), Poly(4,4'-trifluorisopropylidenbisphenol-co-epichlorhydrin), Poly(4,4'-hexafluorisopropylidenbisphenol-co-epichlorhydrin), Poly(4,4'-sulfonylbisphenol-co-epichlorhydrin), Poly(bisphenol-AF-Adipinsäureester), Poly(bisphenol-AF-Succinsäurester), Poly(4,4'-hexafluorisopropylidendiphthalat-co-epichlorhydrin), Poly(4,4'-hexafluorisopropylidendiphthalat-co-poly(bisphenol-AF), Poly(4,4'-hexafluorisopropylidenbisbenzoat-co-epichlorhydrin), Poly(3,3',4,4'-benzophenon-tetracarboxylat-co-epichlorhydrin), Poly(4,4'-hexafluorisopropylidendiphthalat-co-epichlorhydrin-co-2,6-bis[hydroxymethyl]-p-cresol), Poly(3,3',4,4'-benzophenontetracarboxylat-co-epichlorhydrin-co-2,6-bis[hydroxymethyl]-p-cresol), Poly(terephthalat-co-epichlorhydrin), Poly(2-nitroterephthalat-co-epichlorhydrin), Poly(2-nitrophthalat-co-epichlorhydrin), Poly(2-nitroisophthalat-co-epichlorhydrin), Poly(hydrochinon-co-epichlorhydrin), Poly(methylhydrochinon-co-epichlorhydrin), Poly(1,2,4-benzentriol-co-epichlorhydrin), Poly(methylen-bis[4-aminophenyl]-co-glycerincarbamat), Poly(isopropylidenbis[4-aminophenyl]-co-glycerincarbamat), Poly(isopropyliden-bis[3-carboxy-4-aminophenyl]-co-glycerincarbamat), Poly(methylen-bis[4-hydroxyphenyl]-co-glycerincarbonat), Poly(isopropyliden-bis[4-hydroxyphenyl]-co-glycerincarbonat), Poly(isopropyliden-bis[3-carboxy-4-hydroxyphenyl]-co-glycerincarbonat), Poly(2-phenyl-1,3-propandiolmalonat), Poly(2-phenyl-1,3-propandiol-2-methyl-malonat), Poly(1,3-propandiol-benzylidenmalonat), Poly(2-phenyl-1,3-propanediol benzylidene malonate), glycidyl end-capped poly(bisphenol A-co-epichlorohydrin), and silicon-containing anti-reflective coating A940 from Shin Etsu. Another more specific sub-material features the random copolymer poly(styrene-co-epoxy dicyclopentadiene methacrylate), P(Sr-EDCPMA): where x and y are each integers greater than 1:

[0078] Other backing materials include Poly(styrene-co-methyl methacrylate-co-epoxydicyclopentadiene methacrylate), Poly(styrene-co-methyl methacrylate-co-glycidyl methacrylate), Poly(styrene-co-methyl methacrylate-co-2-hydroxyethyl methacrylate), Poly(styrene-co-methyl methacrylate-co-4-vinyl cinamamate), Poly(styrene-co-methyl methacrylate-co-vinyl-benzocyclobutane), poly(styrene-co-vinyl-benzocyclobutane), poly(alpha-methylstyrene-co-methyl methacrylate), and poly(methyl glutarimide) (PMGI).

[0079] Other backsheet materials include polymer brush materials, including hydroxyl-terminated poly(styrene-co-methyl methacrylate), poly(styrene-co-methyl methacrylate-co-2-hydroxyethyl methacrylate), hydroxyl-terminated poly(styrene), hydroxyl-terminated poly(methyl methacrylate), poly(styrene-b-methyl methacrylate) block copolymers, and combinations of the above materials.

[0080] Other underlayer materials include self-assembled monolayers.

[0081] A layer having an underlayer (e.g., a neutral layer, a non-neutral layer) may, for example, contain a thin dielectric material with a thickness between 1 nm to 20 nm.

[0082] The raised surfaces of the hybrid prestructure comprise a neutral underlayer material with substantially the same affinity for each block of a BCP used for self-assembly. The recessed surfaces may comprise a neutral underlayer material or a non-neutral underlayer material with a preferential affinity for fewer than all blocks of a BCP used for self-assembly, typically one block. In one embodiment, the neutral underlayer material and / or the non-neutral underlayer material are random copolymers. In another embodiment, the neutral underlayer material and / or the non-neutral underlayer material contain an etch-resistant material.

[0083] The mechanism for alignment control by the underlayer material in any particular context is complex. Without being bound by any particular theory, the mechanism for alignment control by the underlayer material can depend on net surface energy, wetting properties, surface energy distribution, hydrogen bonding, net dipole moments, dipole moment density, and / or composition. Underlayer surfaces that possess the desired properties can include: cross-linked organic polymers, including an epoxy-based homopolymer or copolymer; organic homopolymers or copolymers; self-assembled monolayers; polymer brushes; cross-linked organosilicates; random copolymer brushes; random cross-linked copolymers; blends of polymer brushes or cross-linked polymers; ARC materials; oxidized silicon; and combinations of the above materials. Surface modification to control alignment

[0084] Polymer brushes can provide a modified surface that is neutral or non-neutral to the SA material. A modified surface can be formed by reactively modifying a surface to a desired thickness and surface properties using polymer brush precursors with a desired composition, often followed by an additional rinsing step to remove unbound material. The composition of the random copolymer brush layer can be optimized to achieve the desired surface properties. This can be achieved in some cases by randomly copolymerizing two monomers in an exact ratio, for example, the same monomers used in the preparation of a block copolymer for self-assembly.In cases where other suitable self-assembly materials (e.g., those capable of forming domains) exist for which synthesis of random copolymers and the repeating units of all polymer block components is not feasible (since different polymerization mechanisms would be required), end-group functionalization or the incorporation of monomer-containing reaction groups can be used to functionalize polymers to provide grafting sites. Thermally cross-linkable sublayers based, for example, on vinylbenzocyclobutene can also be used. Photopatternable sublayers based on random copolymers of the monomers of the self-assembly material with a suitable functional monomer, such as monomers containing azide, glycidyl, or acryloyl groups, can also be used.

[0085] The undercoat surface may also be a coating of a crosslinked epoxy-containing polymer obtained from monomers, including glycidyl (meth)acrylate, 2,3-epoxycyclohexyl (meth)acrylate, (2,3-epoxycyclohexyl)methyl (meth)acrylate, 5,6-epoxynorbornene (meth)acrylate, epoxydicyclopentadienyl (meth)acrylate, and combinations comprising at least one of the above components. When "(meth)acrylate" is used herein, it refers to an acrylate or methacrylate unless otherwise specified. In some embodiments, for example, particularly useful monomers include glycidyl methacrylate and epoxydicyclopentadienyl methacrylate.

[0086] Epoxy-containing polymers also include copolymers or terpolymers that further contain at least one other monomer in addition to the epoxy-containing monomers.Other exemplary monomers include methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, hexyl (meth)acrylate, cyclohexyl (meth)acrylate, benzyl (meth)acrylate, ethylcyclopentyl (meth)acrylate, methylcyclopentyl (meth)acrylate, dicyclopentyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-Hydroxypropyl (meth)acrylate, hydroxyadamantyl (meth)acrylate, adamantyl (meth)acrylate, methyladamantyl (meth)acrylate, ethyladamantyl (meth)acrylate, phenyladamantyl (meth)acrylate, hydroxyadamantyl (meth)acrylate, isobornyl (meth)acrylate, benzyl (meth)acrylate, Gamma-butyrolactone (meth)acrylate, 5-methacryloxy-2,6-norbornane carbolactone, 5-Acryloxy-2,6-norbornane-carbolactone, 2,2,2-trifluoroethyl (meth)acrylate, 1,1,1,3,3,3-hexafluoroisopropyl (meth)acrylate, styrene, 4-methylstyrene, α-methylstyrene, 4-hydroxystyrene, 4-acetoxystyrene, ethylene, propylene, 1-butene, 1,3-butadiene, vinyl acetate, dihydropyran, norbornene, maleic anhydride or a combination with at least one of the above further monomers.The composition of the epoxy-containing polymer can be adjusted by varying the ratios and identities of the comonomers and / or by selecting the structure and / or functionality of the side group(s) on the (meth)acrylates.

[0087] Particularly useful epoxy-containing polymers include poly(epoxydicyclopentadienyl methacrylate) homopolymer or poly(styrene-ran-epoxydicyclopentadienyl methacrylate), a random copolymer of styrene and epoxydicyclopentadienyl methacrylate.

[0088] Organosilicate or silicon oxide-based coatings on the substrate can also be used to provide an underlayer surface. Suitable surfaces can be provided by depositing silicon dioxide or organosilicate as a vapor-deposited layer or as a spin-on layer (spin-on organic glass, abbreviated OSG). Organosilicones, organo- or hydridosilsesquioxanes, or hybrid systems of these materials can be used to provide the underlayer surface if these organosilicate coatings are advantageously crosslinkable to form a solid underlayer surface. Useful organosilicates include those derived from acid- or base-catalyzed hydrolytic condensation of hydridotrialkoxysilanes, alkyltrialkoxysilanes, alkyltrihalosilanes, dialkyldialkoxysilanes, dialkyldihalosilanes, tetraalkoxysilanes, bis(alkylenetrialkoxysilanes), and the like.Exemplary alkoxysilanes useful for preparing organosilicates include hydridotrimethoxysilane, hydridotrimethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, methyltrimethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, propyltrimethoxysilane, propyltriethoxysilane, cyclohexyltriethoxysilane, phenyltriethoxysilane, tetramethoxysilane, tetraethoxysilane (TEOS), 1,2-ethylenebis(triethoxysilane), vinyltrimethoxysilane, vinyltriethoxysilane, glycidoxypropyltrimethoxysilane, epoxycyclohexylethyltriethoxysilane, (meth)acryloxypropyltrimethoxypropylsilane, (meth)acryloxypropyltriethoxypropylsilane, combinations thereof, and the like.

[0089] An underlayer (e.g., neutral layer, non-neutral layer, photoresist layer, fill layer, substrate layer) may comprise an etch-resistant material, including, but not limited to, a material selected from hydrogen silsesquioxane, methyl silsesquioxane, an alkyl silsesquioxane, an alkene silsesquioxane, an aryl silsesquioxane, an arylene silsesquioxane, a silicon-based photoresist, an inorganic photoresist, a silicon-based ARC, a metal-based ARC, silicon oxide, a silicon oxynitride, a silicon-based spin-on dielectric, a metal, a metal oxide, a metal nitride, a metal oxynitride, and a metal carbide, provided that a suitable etch chemistry exists to selectively remove some regions of a self-assembled material from other regions and the etch-resistant material. In one embodiment, the etch-resistant material may include hydrogen silsesquioxane.

[0090] A layer of such an etch-resistant material formed on the substrate may be deposited by any suitable method and is not particularly limited. If the etch-resistant material is soluble in solutions, the application of an etch-resistant material layer to a surface of the substrate may be performed by any method including, for example, spin-coating, dip-coating, knife-coating, spray-coating, or any other suitable method usable with the processes and apparatus used in microelectronics manufacturing facilities. Exemplary casting solvents include, but are not limited to, toluene, propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monomethyl ether (PGME), ethoxyethyl propionate, anisole, ethyl lactate, 2-heptanone, cyclohexanone, amyl acetate, n-butyl acetate, γ-butyrolactone (GBL), aqueous solutions, acetone, and a combination of the above casting solvents.

[0091] In another example, the etch-resistant material may be deposited from the vapor phase by a process including chemical vapor deposition (CVD), plasma-enhanced CVD, atomic layer deposition (ALD), sputtering, thermal evaporation, electron beam evaporation, pulsed laser deposition, and any other suitable deposition method usable with the processes and apparatus used in microelectronics manufacturing equipment.

[0092] An underlayer material may be applied by any suitable method and is not particularly limited. If a polymer-based underlayer material is desired, the application of such layers to a surface of the substrate may be performed by any method including, for example, spin coating, dip coating, knife coating, spray coating, or any other suitable coating method usable with the processes and equipment used in microelectronics manufacturing facilities.

[0093] Solvents that can be used to cast underlayer materials onto a substrate vary depending on the solubility requirements of those materials. Example casting solvents include, but are not limited to: toluene, propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monomethyl ether (PGME), ethoxyethyl propionate, anisole, ethyl lactate, 2-heptanone, cyclohexanone, amyl acetate, n-butyl acetate, γ-butyrolactone (GBL), and acetone.

[0094] The surface energy or composition required for a backsheet material depends on the application. For example, to produce vertically aligned lamellae made of polystyrene (PS)-poly(methyl methacrylate) (PMMA), a PS-r-PMMA random copolymer layer can be used as a neutral backsheet material.

[0095] As another example, for a non-structured surface, a brush composition may comprise 57 to 70% polystyrene (PS). However, the ideal underlayer material for a structured surface (e.g., one with a chemical prestructure) may be different from that designed for a non-structured surface, and the ideal underlayer material may depend on the composition of the guiding portion of the chemical structure (e.g., PS or PMMA preferred) and the multiplication factor, as described in Liu et al., “Chemical Patterns for Directed Self-Assembly of Lamellae-Forming Block Copolymers with Density Multiplication of Features,” Macromolecules, 2013, 46, 1415-1424. The multiplication factor for spatial frequency multiplication refers to the ratio of the pitch of the chemical prestructure to the periodicity of a self-assembling material. The ideal underlayer material may be different for different BCP morphologies (e.g.,vertical cylinders versus slats).

[0096] For a given underlayer material, the performance and surface properties of the material can depend on various factors. For example, the performance and surface properties of an underlayer-modified substrate can depend on the thickness of the underlayer material, the surfaces beneath the underlayer materials, the processing conditions of the underlayer materials, as well as the topography and structural density of the substrate where the underlayer is applied to control surface properties. The molecular architecture of the underlayer material can have an influence. For example, a polymer brush underlayer material may have a composition range that differs from that of a cross-linked underlayer material due to the mobility difference of the brush.For the same reason, a higher molecular weight brush may behave differently than a lower molecular weight brush. Similar changes in the effectiveness of alignment control can be observed for cross-linked underlayer materials with the same composition but different molecular weights. The effectiveness of alignment control can also depend on the thickness of the self-assembly material layer above the underlayer according to the relative difference in surface free energies between the polymer block components. The exact alignment of polymer domains at the air interface or the polymer / underlayer interface need not be perpendicular to the substrate, even if the majority of each polymer domain is oriented perpendicularly. The underlying material can still function, even if it is weakly preferential. Substrat

[0097] The substrate may comprise inorganic or organic materials, such as metals, carbon, or polymers. In particular, the substrate may comprise a semiconductor material, including, for example, Si, SiGe, SiGeC, SiC, Ge alloys, GaAs, InAs, InP, as well as other III-V or II-VI compound semiconductors. The substrate may also comprise a layered semiconductor, such as Si / SiGe, or a semiconductor-on-insulator (SOI). In particular, the substrate may comprise a Si-containing semiconductor material (i.e., a semiconductor material that includes Si). The semiconductor material may be doped, undoped, or contain both doped and undoped regions therein.A substrate comprising a surface affinity material such as natural silicon oxide, silicon oxide, or silicon nitride can be preferentially wetted, for example, by PMMA block components, but not by PS block components of a PS-b-PMMA block copolymer. Therefore, surfaces comprising these surface affinity materials can guide the self-assembly of a PS-b-PMMA block copolymer through chemical epitaxy. The substrate can have a top ARC layer or a bottom ARC (BARC) layer to reduce the reflectivity of the film stack. Many suitable BARCs are known in the literature, including single-layer BARCs, bi-layer BARCs, graded BARCs, and developable BARCs (DNARCs).The substrate may also include a hard mask, a transfer layer (e.g., planarization layer, spin-coated glass layer, spin-coated carbon layer), and other materials as required for a layered device. lithograph

[0098] Various irradiation types can be used in the process of forming a hybrid pre-structure, including ultraviolet (UV) radiation with wavelengths from 400 nm to 300 nm, deep ultraviolet (DUV) radiation with wavelengths from 300 nm to 150 nm, extreme ultraviolet (EUV) radiation with wavelengths from 120 nm to 4 nm, electron beam (e-beam) radiation, X-rays, and combinations of the above. Examples of radiation sources include single-wavelength and / or narrow-band sources, special mercury emission lines, lasers, and particle beam emitters. Under less stringent conditions, a broadband multi-wavelength source can be used. In particular, the radiation wavelength for the structural exposure may be, for example, 405 nm, 313 nm, 334 nm, 257 nm, 248 nm, 193 nm, 197 nm, 126 nm or 13.5 nm.More specifically, the wavelength of the radiation for the patterned exposure may be below 250 nm. In one embodiment, the radiation wavelength is selected from the group consisting of 248 nm, 193 nm, 157 nm, and 13.5 nm.

[0099] The in-plane structures with high etch resistance (raised surfaces) and low etch resistance (recessed surfaces) of the hybrid pre-structure can be fabricated using various methods known in the art. For example, direct writing of structures can be achieved by exposing a polymer (e.g., a surface-bound polymer brush or a self-assembled monolayer) in an e-beam direct write lithographic process or an EUV interference lithography process. Alternatively, a conventional photoresist can be patterned on a sublayer (e.g., neutral layer, non-neutral layer) to form patterned photoresist features.The photoresist structure can protect the underlying surface during an etching process that creates non-neutral surfaces (e.g., areas with a specific affinity for a region of a self-assembled material) either by removing the underlayer material to expose the underlying substrate or by inducing sufficient damage to the underlying material that it preferentially becomes one of the self-assembled regions of the SA material. The protective photoresist layer can then be removed by rinsing with an organic solvent to expose the underlayer with the desired surface properties.

[0100] Instead of selectively removing or altering the underlayer material, negative-mode photopatternable underlayer materials have been developed that can be patterned on conventional anti-reflective coatings. Alternatively, direct patterning of a cross-linked negative-mode photoresist on an underlayer material can create a chemical structure. For best performance, a hydrogen silsesquioxane e-beam negative photoresist was used (used in Example 6).

[0101] A number of schemes compatible with conventional 193 nm immersion lithography have been reported as equally suitable, for example, the first-patterned-finally neutralized scheme described by Cheng et al., "Simple and Versatile Methods To Integrate Directed Self-Assembly with Optical Lithography Using a Polarity-Switched Photoresist," ACS Nano, 2010, 4, 4815-4823. In an alternative method described by Liu et al., "Fabrication of Lithographically Defined Chemically Patterned Polymer Brushes and Mats," Macromolecules, 2011, 44, 1876-1885, a photoresist is patterned on a cross-linked mat (in this case, a cross-linked poly(styrene)). A subsequent etching process is used to break the mat into the underlying substrate and to laterally trim the cross-linked mat.The photoresist is removed and an underlayer material is grafted onto the areas of the substrate not covered by the cross-linked poly(styrene) mat.

[0102] Other techniques that can be used to create suitable structures include nanoimprint lithography, polymer inking / embossing, molecular transfer printing, dip-pen lithography, and nanoprobe lithography (including thermal, electron emission, and other variants).

[0103] Any known method for creating topographical structures known in the art can be used to create the hybrid pre-structures. The topographical structures can consist of a photoresist (either cross-linked or otherwise stabilized), an anti-reflection coating (e.g., a bottom anti-reflection coating (BARC), a developable bottom anti-reflection coating (DBARC), a photosensitive bottom anti-reflection coating (PS-BARC), a silicon anti-reflection coating (SiARC), an inorganic or metallic hard mask layer, an organic planarization layer, a spin-deposited carbon layer, a dielectric layer, a CVD carbon layer, an inorganic oxide layer, an inorganic nitride layer, and / or an inorganic carbide layer).The bottom surface of the topographic pre-pattern can consist of an underlying material or another material with optimized surface properties. One method for preserving the surface properties of the underlying material is to use a negative imaging process with an organic developer to image a cross-linkable (or thermally curable) photoresist on top of the underlayer material. A polymer brush can be grafted onto one or more surfaces of the topographic pattern. Another means of creating graphoepitaxial templates is to use so-called sidewall image transfer (or self-aligned double patterning) techniques, in which a suitable inorganic material is applied via a mandrel (usually by chemical vapor deposition or a similar process).The mandrel can be removed to create a topographical structure with twice the spatial frequency. Variations of this process can be used to create topographical structures with three or four times the frequencies of the initial mandrel structure. Self-organization materials

[0104] SA materials consist of immiscible materials that can be phase separated into regions. Phase separation can occur in various types of polymer blends (e.g., binary, ternary) as well as in block copolymers, which have two or more immiscible polymer block components. The term "immiscible," as used herein, refers to two or more components (e.g., blocks of a block copolymer, polymers of a polymer blend, and the like) that are sufficiently incompatible to be phase separated under certain process conditions.

[0105] SA materials for guided self-assembly can comprise immiscible polymer blends. The immiscibility of the polymers in the polymer blends can depend on the composition as well as the film formation process of the polymer blends. The ratio of the polymers, molecular weights of individual polymers in the blend, and the presence of other additional components in the blend can be used to adjust the compatibility of the polymers in the polymer blend. Temperature, coating conditions, and properties of the sublayer surface can also influence the phase separation of the polymers. As used in this document, an "immiscible polymer" is a polymer that is deposited under suitable process conditions in a polymer blend formation phase onto a properly prepared sublayer surface.

[0106] Examples of polymers for the two or more immiscible polymer blends include: cellulose, poly(acrylamide), polyethylene, poly(acrylic acid), poly(2-ethyl-2-oxazoline), poly(ethylene oxide) and poly(vinyl alcohol), novolak resins, cresol resins, poly(hydroxystyrene), poly(acrylic acid), poly(styrenesulfonic acid), poly(vinylphosphoric acid), poly(vinylsulfonic acid), poly(2-sulfoethyl methacrylate), poly(2-sulfopropyldimethyl-3-methacrylamide), poly(1,1,1-trifluoro-2-trifluoromethyl)-2-hydroxy-pentan-4-yl methacrylate), fluoroalcohol-based polymers, poly(2-ethyl-trifluoromethanesulfonamide methacrylate), acid sulfonamide polymers, poly(styrene), poly(hydroxyadamantyl methacrylate), poly(isobornyl methacrylate), poly(phenyl methacrylate), poly(vinyl naphthalene), Polysiloxanes, polymethylsilsesquioxanes, polycarbosilanes, poly(vinylferrocene), poly(acylonitrile), poly(caprolactone), poly(lactide), poly(methyl methacrylate), poly(2-hydroxyethyl methacrylate), poly(gamma-butyrolactone methacrylate),Poly(tetrahydrofuranyl methacrylate), poly(tetrahydropyranyl methacrylate), poly(allylamine), poly(4-aminostyrene), poly(2-dimethylaminoethyl methacrylate), polyethyleneimine, poly(N-methylvinylamine), poly(vinylpyridine), poly(isoprene), poly(butadiene), poly(nobornene), poly(ethylene), poly(propylene), poly(1, 1, 1-trifluoro-2-(trifluoromethyl)-2-hydroxy-pentan-4-yl methacrylate), fluoroalcohol-based polymers, poly(2-ethyl trifluoromethanesulfonamide methacrylate), acidic fluorosulfonamide polymers, poly(2,2,2-trifluoroethyl methacrylate), poly(hexafluoroisopropyl methacrylate), poly(2,3,4,5,6-pentafluorostyrene) and replaced derivatives thereof. The two or more immiscible polymers may be selected so that each polymer is immiscible with any other polymer in the mixture.

[0107] The SA material may comprise a block copolymer or blends of block copolymers and other polymers. In one embodiment, the block copolymer consists essentially of a first polymeric block component A and a second polymeric block component B, which are immiscible with each other. Typically, homopolymers of suitable immiscible block components form a blend representing multiple glass transition temperatures representative of each homopolymer phase. Preferably, one of components A and B is selectively removable without requiring removal of the other, so as to form isolated and systematically arranged structural units composed of the unremoved component or a continuous structural layer containing isolated and systematically arranged voids formed upon removal of the removable component.Alternatively, components A and B may simply have different electrical, optical and / or magnetic properties, so that the ordered structures composed of such components A and B can be used to fabricate different device structures.

[0108] The block copolymer may comprise blocks containing one or more monomers, and at least two blocks within the block copolymer are not identical due to composition, structure, or both composition and structure. Exemplary block copolymers include diblock copolymers, triblock copolymers, or multiple block copolymers, any of which may be used in conjunction with DSA to further improve resolution. The blocks themselves may be homopolymers or copolymers, including terpolymers.The SA material forming the phase-separated structures of chemically distinct regions may comprise an amphiphilic organic block copolymer, an amphiphilic inorganic block copolymer, an organic diblock copolymer, an organic multi-block copolymer, a diblock copolymer containing an inorganic component, a multi-block copolymer containing an inorganic component, a linear block copolymer, a block star copolymer, a dendritic block copolymer, a hyperbranched block copolymer, a graft block copolymer, a bottlebrush copolymer, or a combination comprising at least one of the above block copolymers. In one embodiment, the block copolymer is a diblock copolymer. A combination of a suitable triblock copolymer and a chemical precursor may be used, for example, to quadruple the spatial frequency of the chemical precursor.

[0109] In general, any suitable microdomain-forming block can act as a block component, which may be copolymerized, attached to, or self-assembled with another dissimilar block. Blocks can be derived from various polymerizable monomers, which blocks may include, but are not limited to: polyolefins, including polydienes; polyethers, including poly(alkylene oxides) such as poly(ethylene oxide), poly(propylene oxide), poly(butylene oxide), or random or block copolymers thereof; poly((meth)acrylates), polystyrenes, polyesters, polyorganosiloxanes, polyorganogermanes, and the like.

[0110] In one embodiment, the blocks of the block copolymer comprise repeating units derived from C 2-30 olefinic monomers, (meth)acrylate monomers derived from C 1-30-alcohols, inorganic component-containing monomers including those based on Fe, Si, Ge, Sn, Al, Ti, or a combination comprising at least one of the above monomers. In a specific embodiment, exemplary monomers for use in the blocks may be the C 2-30Olefinic monomers include ethylene, propylene, 1-butene, 1,3-butadiene, isoprene, vinyl acetate, dihydropyran, norbornene, maleic anhydride, styrene, 4-hydroxystyrene, 4-acetoxystyrene, 4-methylstyrene, or alpha-methylstyrene; and (meth)acrylate monomers may include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, n-pentyl (meth)acrylate, isopentyl (meth)acrylate, neopentyl (meth)acrylate, n-hexyl (meth)acrylate, cyclohexyl (meth)acrylate, isobornyl (meth)acrylate, or hydroxyethyl (meth)acrylate. Combinations of two or more of these monomers may be used.Exemplary blocks used for homopolymers include blocks made with styrene (e.g., polystyrene blocks) or (meth)acrylate homopolymer blocks, such as poly(methyl methacrylate); exemplary random blocks include, for example, randomly copolymerized blocks of styrene and methyl methacrylate (e.g., poly(styrene-co-methyl methacrylate)); and an exemplary alternating copolymer block may contain blocks of styrene and maleic anhydride, which is known to form a styrene-maleic anhydride binary repeating structure due to the inability of maleic anhydride to homopolymerize under most conditions (e.g., poly(styrene-alt-maleic anhydride)), where "-alt-" indicates alternating polymer blocks. It is understood that such blocks are exemplary in nature and should not be considered limiting.

[0111] More specific diblock or triblock copolymers include poly(styrene-b-vinylpyridine) (PS-b-PVP), poly(styrene-b-butadiene) (PS-b-PBD), poly(styrene-b-isoprene) (PS-b-PI), poly(styrene-b-methyl methacrylate) (PS-b-PMMA), poly(styrene-b-alkenyl aromatics), Poly(isoprene-b-ethylene oxide) (PI-b-PEO), Poly(styrene-b-(ethylene propylene)), Poly(ethylene oxide-b-caprolactone), Poly(butadiene-b-ethylene oxide) (PBD-b-PEO), Poly(styrene-bt-butyl(meth)acrylate), Poly(methyl methacrylate-bt-butyl methacrylate), Poly(ethylene oxide-b-propylene oxide), Poly(styrene-b-tetrahydrofuran), Poly(styrene-b-dimethylsiloxane) (PS-b-PDMS), poly(styrene-b-ferrocenyldimethylsilane) (PS-b-PFS), poly(styrene-b-isoprene-b-ethylene oxide) (PS-b-PI-b-PEO), poly(styrene-b-isoprene-b-methyl methacrylate) (PS-b-PI-b-PMMA), poly(styrene-b-ferrocenyldimethylsilane-b-isoprene) (PS-b-PFS-b-PI), poly(styrene-b-lactide) (PS-b-PLA) or a combination comprising at least one of the above block copolymers.

[0112] Specific examples of self-assembling block copolymers may include, but are not limited to: polystyrene-block-polymethyl methacrylate (PSb-PMMA), polystyrene-block-polyisoprene (PS-b-PI), polystyrene-block-polybutadiene (PS-b-PBD), polystyrene-block-polyvinylpyridine (PS-b-PVP), polystyrene-block-polyethylene oxide (PSb-PEO), polystyrene-block-polyethylene (PS-b-PE), polystyrene-b-polyorganosilicate (PS-b-POS), polystyrene-block-polyferrocenyldimethylsilane (PS-b-PFS), polyethylene oxide-block-polyisoprene (PEO-b-PI), polyethylene oxide-block-polybutadiene (PEO-b-PBD), polyethylene oxide-block-polymethyl methacrylate (PEO-b-PMMA), polyethylene oxide-block-polyethylene (PEO-b-PEE), polybutadiene-block-polyvinylpyridine (PBD-b-PVP), and polyisoprene-block-polymethyl methacrylate (PI-b-PMMA). Other exemplary block copolymers that may be considered for use in the present process include diblock or triblock copolymers, such as poly(styrene-b-alkenylaromatics),Poly(styrol-b-(ethylenpropylen)), Poly(ethylenoxid-b-caprolacton), Poly(styrol-b-t-butyl(meth)acrylat), Poly(methylmethacrylat-b-t-butylmethacrylat), Poly(ethylenoxid-b-propylenoxid), Poly(styrol-b-tetrahydrofuran), Poly(styrol-b-dimethylsiloxan), Poly(vinylpyridin-b-dimethylsiloxan), Poly(ethylenoxid-b-dimethylsiloxan), Poly(methylmethacrylat-b-dimethylsiloxan), Poly(isopren-b-dimethylsiloxan), Poly(isopren-b-vinylpyridin), teilweise epoxidiertes Poly(styrol-b-isopren), Poly(butadien-b-vinylpyridin), Poly(trimethylsilylstyrol-b-Milchsäure), Poly(styrol-b-Milchsäure), Poly(styrol-b-hydroxystyrol), Poly(styrol-b-Acrylsäure), Poly(ethylenoxid-b-hydroxystyrol), Poly(methylmethacrylat-b-vinylpyridin), Poly(ethylenoxid-b-methylmethacrylat-b-styrol), Poly(styrol-b-isopren-b-ethylenoxid), Poly(methylmethacrylat-b-styrol-b-methylmethacrylat), Poly(isopren-b-styrol-b-ferrocenyldimethylsilan), Poly(styrol-b-trimethylsilylstyrol-b-styrol) oder Kombinationen,containing at least one of the above block copolymers.,

[0113] The polymer blends or diblock copolymers may also contain inorganic components, such as homopolymers, copolymers, and block copolymers with inorganic components, as well as monomers with inorganic components, molecules, and additives. These include, for example, those based on silicon, germanium, iron, titanium, aluminum, or similar.

[0114] The block copolymer preferably has a total molecular weight and polydispersity that are adjustable for further processing. In one embodiment, the block copolymer has an average molecular weight (Mw) of 3,000 to 200,000 g / mol. Likewise, the block copolymer has a number-average molecular weight (Mn) of 1,000 to 80,000. The block copolymer can also have a polydispersity (Mw / Mn) of 1.01 to 6, but is not particularly limited thereto. The average molecular weight, both Mw and Mn, can be determined, for example, by gel permutation chromatography using a universal calibration method calibrated to polystyrene standards.

[0115] The diblock copolymers can be prepared by methods previously described in the art, including living polymerization techniques such as atom transfer free radical polymerization (ATRP), nitroxide-mediated radical polymerization, ring-opening metathesis polymerization (ROMP), and living cationic or living anionic polymerizations.

[0116] In a particular embodiment, the block copolymer used to form the self-assembled periodic structures is PS-b-PMMA. The PS and PMMA blocks in such a PS-b-PMMA block copolymer can have a total (summed across all blocks) number-average molecular weight (Mn) in a range of 5,000 to about 300,000, with a total number-average molecular weight of about 10,000 to about 200,000 being more typical. Each block can have an Mn of 2,000 to 100,000, more preferably 5,000 to 60,000.

[0117] The morphology (e.g., shape, dimensions, and orientation) of the self-assembled domains of thin block copolymer films is a function of the composition (e.g., material, molecular weight, and volume ratio of the various blocks), the curing conditions (e.g., temperature, environment, and curing time), the interfacial properties (e.g., polymer-air interface and polymer-substrate interface), and the defined geometry (e.g., film thickness and boundary topography). Therefore, by adjusting one or more parameters, the morphology can be tailored to the requirements of specific applications.

[0118] To form the self-assembled periodic structures, the block copolymer can first be dissolved in a suitable solvent system to form a block copolymer solution, which can then be applied to the treated layer, forming a thin block copolymer layer thereon. Optionally, curing the thin block copolymer layer can assist the self-assembly process of the polymeric block components.

[0119] In one embodiment, the SA material comprises at least one block copolymer. Non-limiting examples of solvents for the SA material include substituted or unsubstituted aromatic carbons, substituted or unsubstituted aromatic ethers, substituted or unsubstituted aromatic alcohols, saturated monoalcohols containing 5 to 20 parts hydrocarbon, ketones, glycol monoethers, and glycol monoether esters. In one embodiment, the SA solvent is a glycol, glycol monoether, or glycol monoether ester, or combinations thereof. More specific solvents for the SA material include, but are not limited to, toluene, ethylene glycol, propylene glycol, propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monomethyl ether (PGME), 4-methyl-2-pentanol, n-butyl acetate, anisole, acetone, and combinations thereof.In one embodiment, the solvent for the SA material is ethylene glycol, propylene glycol, propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monomethyl ether (PGME), 4-methyl-2-pentanol, or combinations thereof. The solutions of the SA material can have a concentration between 0.1 weight percent to about 5 weight percent SA material based on the total weight of the solution. More specifically, the SA material is dissolved at a concentration ranging from about 0.5 weight percent to about 2.5 weight percent. In one embodiment, the solution of the SA material comprises about 0.5 weight percent to about 2.5 weight percent of a PS-b-PMMA block copolymer dissolved in anisole. The SA material solution may optionally further comprise additional block copolymers, homopolymers, random copolymers, surface wetting agents, and photoacid generators, photobase generators, thermal acid generators, thermal base generators, acid enhancers, and photodestructible bases.

[0120] The application of SA materials to a surface of the substrate may be performed by a method including, for example, spin casting, dip coating, doctor blade coating, spray coating, or any other suitable coating method usable with the processes and equipment used in microelectronics manufacturing facilities.

[0121] The SA material solution is cast onto the pre-structure in a casting process, followed by solvent removal, thereby disposing a thin film of SA material on at least one raised surface and at least one depressed surface of the hybrid pre-structure. In one embodiment, the SA material is disposed on substantially all raised and depressed surfaces of the hybrid pre-structure. The SA material solution can be applied using any suitable technique, including, but not limited to, spin casting, roll coating, spraying, ink coating, dip coating, and the like.

[0122] Further curing (including thermal curing, thermal gradient curing, solvent vapor curing, or another gradient field) may optionally be used to remove defects in the SA layer and / or promote self-assembly of the SA material. In particular, the SA layer may comprise a block copolymer that can be thermally cured at a temperature above the glass transition temperature (Tg) of the block copolymer but below the decomposition or degradation temperature (Td) of the block copolymer. The thermal curing step may be performed at a curing temperature of about 100°C to about 300°C. The thermal curing may be performed for a period of time from about 1 minute to about 120 hours, more preferably between 0.5 minutes to 1 hour.The thermally cured block copolymer self-assembles to form ordered domains whose orientation can be perpendicular to the underlying surface plane. Generally, the SA layer can have a thickness of 100 to 10,000 Å, specifically between 200 to 5,000 Å, and even more specifically between 300 to 2,000 Å. Second DSA

[0123] Optionally, after a first self-assembly step, all or substantially all of the first DSA layer comprising self-assembled SA material can be removed from the pre-structures using at least one solvent. In one embodiment, all or substantially all of the first DSA layer is removed from the pre-structure by applying a solvent layer to the first DSA layer and spinning the wafer dry. The application of a solvent layer can be accomplished by any method known in the art, including puddling, spraying, and / or dipping. During the removal process, dynamic wafer movement through controlled rotation or sonication can be used to facilitate removal of the first DSA layer. In another embodiment, a combination of solvents is used.In yet another embodiment, a combination of solvents is used sequentially. In yet another embodiment, the wafer (substrate) is fired after a removal process to remove any remaining solvents.

[0124] After the first DSA layer is removed, a modified pre-structure remains, comprising raised and depressed surfaces that possess the same or substantially the same wetting properties relative to the SA material. It is believed, without being bound by theory, that the raised and depressed surfaces in the SA material are slightly surface-modified relative to the original pre-structure. Thus, the remaining SA material is an underlayer material for the second SA layer. A second SA layer is then formed on the modified pre-structure using the techniques described above in connection with the formation of the first SA layer. Specifically, a (second) solution is prepared comprising one or more SA materials dissolved in a solvent.The solution is poured onto the modified pre-structure, followed by solvent removal, forming a second SA layer. The second solution of SA material may additionally contain other materials, including polymers, block copolymers, wetting agents, photoacid generators, and thermal acid generators. For example, an organosilicate resin miscible with poly(ethylene oxide) domains of the poly(ethylene oxide-block styrene) copolymer may be included. The second SA layer is allowed or induced to self-assemble, and the resulting domains align as guided by the underlying modified pre-structure to form a second domain structure with fewer defects than the first domain structure.

[0125] In this document, the term "defects" refers to those defects that arise from the DSA process itself and is not intended to refer to routine manufacturing defects that are unrelated to the DSA process (e.g., defects related to unwanted foreign particles and / or materials, and line collapse due to the removal of one of the regions). Defects in a self-assembled cylindrical structure include, for example, alignment errors, discontinuous cylindrical regions, and cylinders that do not pass through the SA film. Defects can also be alignment-related; for example, regions may be aligned parallel to the substrate when perpendicular alignment is desired. Self-organization

[0126] The self-assembly of the SA material of the SA layer can occur during film formation, during firing after deposition, or in a subsequent curing process. Suitable curing processes include thermal curing, thermal gradient curing, solvent vapor curing, or curing by other gradient fields. As with the first self-assembled structure, the second self-assembled structure comprises a first region and a second region of the SA material. The first and second regions comprise different components of SA material; that is, they differ in their composition. For example, the first region may comprise one block of a block copolymer, and the second region may comprise another block of a block copolymer. etching

[0127] One of the regions can be selectively removed (e.g., ion-etched) or modified in the presence of the other region to create a topographical or chemical contrast. Selective removal of one of the regions may also remove underlayer material and / or substrate layer material. The resulting relief structure of the openings may have a spatial frequency greater than that of the chemically patterned surface. The selected removal process may be performed by thermal firing (for thermally decomposable materials), a reactive ion etching process, dissolution in a selected solvent, or a combination thereof. Chemical modification may be achieved using a variety of known materials.For example, regions can be selectively reacted with silanes or silychlorides to introduce silicon content into a region and thereby increase resistance to plasma etching. Alternatively, chemical agents can be used to bond or chemically attach functional groups located exclusively in one type of self-assembled region, for example, to create differences in increased solubility properties that can be advantageously used to selectively remove one region in the presence of the other region. Chemical infiltration from a liquid phase can also be used to selectively deposit materials with high etch resistance onto a region in the block copolymer.The synthesis of sequential infiltration of high etch resistance materials can also be used to increase the selected etch resistance of block copolymer regions (for example, forming aluminum in a PMMA region by infiltrating trimethylaluminum into the PMMA region and reacting the trimethylaluminum with water to form aluminum).

[0128] The differences in etch rates between two ordered regions of the block copolymer and between the underlying materials of the raised and recessed surfaces of the pre-structure enable the creation of complex and customized structures. Selective removal of at least one self-assembled region by etching, solvent, or other means creates a nanoscale relief structure, for example, a pattern of line arrangements that can be transferred into the underlying substrate. The line arrangements can be further customized during transfer to the substrate.

[0129] Etching methods include all common etching techniques used in semiconductor device manufacturing, such as dry etching such as plasma etching or wet etching using selected solvents. Dry etching processes are typically used for etching in dimensions below 50 nm.

[0130] Before this area structure development / structure transfer, the self-assembled layer of the SA material can optionally be chemically modified to improve the properties required for structure transfer, such as etch resistance or mechanical properties.

[0131] Pattern transfer can be facilitated by a material stack. The material stack can include a hard mask layer, an etch-resistant inorganic layer typically located above an organic transfer layer. The material stack can include an organic transfer layer directly beneath the chemically patterned layer. In one embodiment, the material stack can provide etch selectivity required to transfer the composite structure to the underlying layers.

[0132] In certain cases, inversion of the transferred structure may be desirable, which can be achieved in several ways. In one illustrative example, voids formed by transferring the structure to the organic transfer layer can be filled with a filler material, such as a spin-on dielectric (SOD) material that exhibits etch selectivity with respect to the organic transfer layer in an etch. Optionally, the filler material can be treated to promote cross-linking or curing. The organic transfer layer can be selectively removed with respect to the filler material to form a complementary structure incorporating the filler material portions.

[0133] Also disclosed is a layered structure formed by any of the methods described above. In one embodiment, the layered structure is a semiconductor device. The method can be used to form layered structures including metal wire lines, openings for contacts or vias, isolation sections (e.g., damascene trenches or shallow trench isolation), and trenches for capacitor structures suitable for the construction of integrated circuit devices. The method can be useful for creating patterned layers of oxides, nitrides, or polysilicon.

[0134] When the SA material is a block copolymer or a blend with a block copolymer, the method advantageously enables the self-assembled structures to have a reduced feature width and increased periodicity with respect to the pre-structure feature(s). In this case, the width of the domain feature can be between 1 and 50 nm, between 1 and 30 nm, or more specifically between 1 and 20 nm. When the SA material is an immiscible polymer blend, the method enables a photoresist feature size to be below 500 nm, in particular below 150 nm, and more specifically below 100 nm. The domain feature size is more likely to be somewhat larger, between 1 and 500 nm, between 1 and 250 nm, or more specifically between 1 and 150 nm. Second, the method advantageously utilizes a self-assembled material with a reduced feature size and increased periodicity with respect to the pre-structure.

[0135] The following non-limiting examples are now presented to further illustrate the disclosed methods. EXAMPLES

[0136] The materials used in the following examples are listed in Table 1. Table 1. ABKÜRZUNG BESCHREIBUNG LIEFERANT ODL-401 Organische Hartmaske Shin Etsu SHB A-940 L10 Silizium-Antireflexionsbeschichtungsschicht Shin Etsu PGMEA Propylenglycolmethyletheracetat Sigma-Aldrich S Styrol MW 104.15 MMA Methylmethacrylat Sigma-Aldrich GMA Glycidylmethacrylat; MW 142.2 AZ PME 120 Poly(styrol-b-methylmethacrylat)-Block-Copolymer, PS-b-PMMA, Mn = 22.000 pro Block AZ Electronic ArF AIM7210JN-8 193i Fotolack JSR P(S-r-EDCPMA) Statistisches Poly(styrol-co-epoxydicyclopentadienmethacrylat)-Copolymer AZ NLD 201 Material zum Ausbilden einer neutralen Schicht AZ Electronic TMAH 0,26 N Tetramethylammoniumhydroxid, Entwickerlösung, OPTIYIELD CD Fuji Film HM8500 Carbon hard mask layer JSR AZ PME 751 PS-b-PMMA block copolymer, 27.5 nm pitch AZ Electronic AZ NLD 226 Surface modification materials AZ Electronic P(Sr-EDCPMA) Poly(styrene-co-epoxydicyclopentadiene methacrylate) random copolymer (S:EDCPMA = 70:30 mol percent, Mn = 5,800) Prepared below P(Sr-MMA-r-GMA) Poly(styrene-co-methyl methacrylate-co-glycidyl methacrylate) random copolymer (ratio of S:MMA:GMA = 56:42:2 mole percent, M n = 12.1 kg / mol) Prepared below HSQ XR-1541 hydrogen silsesquioxane electron beam negative photoresist Dow Corning QZ3501 Edge bead remover; gamma-butyrolactone / butyl acetate developer Fuji Film Production of P(Sr-MMA-r-GMA) and its formulation

[0137] Poly(styrene-co-methyl methacrylate-co-glycidyl methacrylate) random copolymer was prepared by free radical polymerization of styrene, methyl methacrylate and glycidyl methacrylate in a molar addition ratio of 58:40:2 (isolated polymer composition: 56:42:2 as determined by 13C NMR). Mn=12.1 kg / mol. PDI: 1.59. A PGMEA solution of P(Sr-MMA-r-GMA) and p-NBT (p-nitrobenzyl tosylate) [95:5 w / w ratio] was used for the formulation to form an underlayer for PS-b-PMMA. See Cheng et al., "Simple and Versatile Methods To Integrate Directed Self-Assembly with Optical Lithography Using a Polarity Switched Photoresist," ACS Nano, 2010, 4, 4815-4823, for details on the preparation of this material. Preparation of P(Sr-EDCPMA) and its formulation

[0138] Poly(styrene-co-epoxydicyclopentadiene methacrylate) random copolymer, P(Sr-EDCPMA), was prepared by free radical polymerization of styrene and epoxydicyclopentadiene methacrylate in a 70:30 molar ratio according to the process described in U.S. Patent 7,521,090 with Mn=5819 g / mol. PDI: 1.51. A PGMEA solution of poly(styrene-co-epoxydicyclopentadiene methacrylate) and N-phthalimide triflate (95:5 w / w ratio) was used for the formulation to form a sublayer for the SA material PS-b-PMMA.

[0139] Example 1: Functional example of DSA on various hybrid pre-structures produced by a backfill process. The following layer diagrams serve to illustrate this.

[0140] A silicon wafer substrate (12.7 cm (5 in) diameter) was coated with a 50 nm thick organic hard mask ("ODL", Shinetsu ODL-401) and a 10 mm thick anti-reflective silicon coating layer ("SiARC", Shinetsu SHB A-940 L10) to form the formation stack of the hybrid pre-structure. The stack was treated with an oxygen-reactive ion etch (O2 RIE) for 45 seconds to oxidize the SiARC surface. A PGMEA solution containing a random copolymer of styrene (S), methyl methacrylate (MMA), and glycidyl methacrylate (GMA), P(Sr-MMA-r-GMA)), and a thermal acid generator was then cast onto the oxidized SiARC stack, baked for 2 minutes at 215°C, and then rinsed with PGMEA to remove any non-crosslinked P(Sr-MMA-r-GMA), forming a neutral underlayer (neutral UL).The neutral underlayer, a poly(styrene)-b-poly(methyl methacrylate) block copolymer (PS-b-PMMA), referred to below, was neutral-wetting for the SA material. The P(Sr-MMA-r-GMA) is referred to as the "neutralization material." A 60 nm thick 193i photoresist ("7210", JSR ArF AIM7210JN-8) layer was then coated onto the top surface of the neutral UL. The photoresist layer was pattern-exposed using 193 nm interference lithography and developed in negative mode (unexposed areas removed) with an organic developer (2-heptanone) to create a grating prestructure with a pitch of 168 nm, 196 nm, and 224 nm, which allows a 6-, 7-, and 8-fold multiplication of the self-assembled lamellar regions for the PS-b-PMMA block copolymer with a pitch of 28 nm, respectively.

[0141] The photoresist pattern was then transferred to the underlying substrate through a series of reactive ion etchings (5 seconds of O2 RIE, 10 seconds of CF4 / H2 RIE, and 10 seconds of O2 RIE), creating an oxidized ODL layer at the bottom of the trenches and an etched photoresist as a mesa. A polarity switch / curing process was performed by exposing the photoresist pattern to a broadband deep ultraviolet (DUV) light from a 500 W Hg / X3 short-arc lamp (UXM-501MA-Ushio America) with a total flood exposure dose of 60 mJ / cm 2, followed by a hard bake at 95 °C for 60 seconds and at 200 °C for 180 seconds. After curing the photoresist, a PGMEA solution containing a poly(styrene-co-epoxydicyclopentadiene methacrylate) random copolymer, P(Sr-EDCPMA), a non-neutral wetting filler material, and a thermal acid generator was poured onto the pre-cured structure and fired at 200 °C for 2 minutes. The concentration and spin rate of the filler material were then adjusted to avoid filling the trenches up to the photoresist features (i.e., the top surface of the filler material was below the bottom interface of the photoresist feature and the neutral underlayer). The filled pre-pattern was then brought into contact with a standard aqueous alkaline developer, 0.26 N tetramethylammonium hydroxide (TMAH), for 30 seconds, followed by a rinse with deionized water (DI water) to remove the cured photoresist pattern.The resulting hybrid prestructure featured alternating depressed surfaces containing non-neutral-wetting fill material and neutral-wetting raised surfaces. The sidewalls had a height H. N of about 0.5 Lo, the sidewalls have a preferential affinity for a region of the self-assembled SA material. In this example, stripping the photoresist did not significantly change the neutral wetting properties of the neutral underlayer surface (raised surfaces).

[0142] A PGMEA solution of the SA material (AZ Electronic PME 120, poly(styrene)-b-poly(methyl methacrylate) block copolymer (PS-b-PMMA)) was then spin-coated at 1,500 rpm onto the pre-pattern shown, and the sample was cured at 225 °C for 5 minutes to form a first DSA structure. After performing a single DSA process, a solvent rinse was performed by pouring PGMEA onto the first DSA structure for 30 seconds and spinning the sample dry to remove all solvent and all or substantially all of the DSA structure. Another spin-coating of AZ PME 120 was then performed at 1,500 rpm, and the sample was cured at 255 °C for 10 minutes to generate second DSA structures with fewer defects than those of the first DSA structures.A short O2 RIE was then applied to partially remove the PMMA region of the DSA structures and to increase the contrast between the PMMA and PS regions for characterization with a scanning electron microscope (SEM).

[0143] Fig. Figure 8 shows the self-assembled block copolymer over a variety of hybrid prestructures with different geometric combinations of W E and W R W E is the width of the raised features that have a neutral layer on the SiARC plates, and W Ris the width of the recessed surfaces containing fill material P(Sr-EDCPMA) in the trenches. The self-assembly of the SA material forms a perpendicularly aligned lamellar line structure with 28 nm pitch rows on the raised surfaces, which are neutral-wetting and have an underlying material with high etch resistance. The PS rows (lamellae) can be transferred to the inorganic SiARC plates to form a composite mask for adapting the DSA arrays. In this example, W E +W R = 6 Lo, 7 Lo or 8 Lo (integer times Lo). As in Fig. As shown in Figure 8, a good DSA was achieved on hybrid prestructures with different combinations of W E and W R A good DSA was also obtained on hybrid prestructures when W E had a value other than 0.5 Lo or 1.5 Lo (for example, if W Ewas about 2 Lo, 3 Lo, 4 Lo or 5 Lo), which is not expected on the basis of conventional chemical epitaxy.

[0144] 2. Example: Determination of W E -Process window for DSA in hybrid prestructures produced by filling processes The general layer diagrams of the first example also apply to the second example.

[0145] Silicon wafer substrates were coated with a 50 nm thick organic hard mask (Shinetsu ODL-401) and 10 mm thick SiARC (Shinetsu SHB A-940 L10) to form the formation stack of the hybrid pre-structure. The stack was treated with O2 RIE for 50 seconds to oxidize the SiARC surface. P(Sr-MMA-r-GMA) with a thermal acid generator was then cast onto the oxidized SiARC stack, fired at 215 °C for 2 minutes, and rinsed with PGMEA to remove any non-crosslinked material and form a neutral underlayer. A 60 nm thick 193i photoresist (JSR ArF AIM7210JN-8) was then coated on the neutral underlayer, pattern-exposed by e-beam lithography (EBL), and developed in negative mode with an organic developer (2-heptanone) to create a lattice prestructure allowing a sixfold multiplication of the self-assembled block copolymer with a pitch of 28 nm.The pre-structures consisted of a number of dies measuring 8.5 µm × 5.8 µm. The pitch of each die was kept constant, while the trench width was systematically varied from 41 nm to 118 nm with a step size of 2 nm to 3 nm.

[0146] The EBL test structures were then transferred to the substrate through a series of RIE etchings (5 seconds of O2 RIE, 11 seconds of CF4 RIE, and 10 seconds of O2 RIE). A polarity change / curing process was initiated by exposing the etched pre-structure to a DUV broadband light from a 500 W short-arc lamp (UXM-501MA-Ushio America) with a total flood exposure dose of 60 mJ / cm 2, followed by a hard bake at 95 °C for 60 seconds and at 200 °C for 180 seconds. After curing the photoresist, a non-neutral filler material P(Sr-EDCPMA) containing a thermal acid generator was then cast onto the cured pre-pattern and fired at 200 °C for 3 minutes. The concentration and spin rate of the filler material were adjusted to avoid filling the trenches up to the photoresist features (i.e., the top surface of the filler material was below the bottom surface of the neutral underlayer). In this case, a 0.2% solution was spin-cast at 4,000 rpm. The filled pre-pattern was then brought into contact with a standard aqueous alkaline developer (0.26 N TMAH) for 60 seconds, followed by a deionized water rinse to remove the cured photoresist pattern.The resulting hybrid prestructure contained neutral-wetting raised surfaces on neutral UL / SiARC plates and non-neutral recessed strips containing fill material arranged in the trenches. The height difference H. NThe sidewall thickness between these two regions was 0.5 Lo. The SA material (block copolymer solution AZ PME 120) was then spin-coated onto the hybrid pre-structure at 1,500 rpm, and the sample was then cured at 255 °C for 5 minutes to form the first DSA structures. After performing a single DSA process, a solvent rinse was performed by pouring PGMEA onto the first DSA structure for 30 seconds and spinning the sample dry to remove all the solvent and all or substantially all of the DSA structure. Another spin-coating of AZ PME 120 was then performed at 1,500 rpm, and the sample was cured at 255 °C for 10 minutes to generate second DSA structures with fewer defects than those of the first DSA structures. The DSA structures were then etched using O2 RIE, revealing the block copolymer regions and the underlying structure.The structures can then be transferred into the stack by performing a carefully measured CF4 RIE followed by an O2 RIE. The samples were then imaged from top to bottom using SEM.

[0147] Fig. Figure 9 is a series of SEMs showing the amount of variation in the width of the raised surfaces W E for a good DSA show if W E to various integer multiples of Lo. In this series, W E +W R = 6 Lo. If W E was approximately 2 Lo (56 nm), a good DSA was achieved over the hybrid pre-structure when W E in the range of about 53 nm to 61 nm. If W E was approximately 3 Lo (84 nm), a good DSA was achieved over the hybrid pre-structure when W E in the range of about 82 nm to 90 nm. If W E was about 4 Lo (112 nm), a good DSA was achieved when W Ein the range of 107 nm to 117 nm. These ranges (8 to 10 nm) represent appropriate process windows for W E represents.

[0148] 3. Example: DSA and the adaptation of DSA arrays over hybrid pre-structures (basic process). The following layer diagrams serve to illustrate this.

[0149] Fig. Figure 10A is a series of cross-sectional layer diagrams showing the basic process flow of the third example for fabricating two hybrid precursors from a patterned photoresist / stack, with the steps numbered in the square boxes below the diagrams. The corresponding SEM images for the two hybrid precursors are shown in Fig. 10B, which are titled “wide” and “narrow”, with the corresponding step number of Fig. 10A in the square box. DSA row structures above the hybrid pre-structures are shown in Fig.10C, which are titled “wide” and “narrow”, where the step number of Fig. 10A is indicated in the square box. Adapted structures are shown in Fig. 10D, which are titled “wide” and “narrow”, where the step number of Fig. 10A is indicated in the square box. The procedure was as follows.

[0150] A stack with a 9 nm anti-reflection silicon layer (“SiARC”, Shinetsu SHB A-940 L9) and a 35 nm carbon hard mask layer (“HM8500”, JSR HM8500) was deposited on a 10 nm SiN x -layer ("SiN x") and a 30 nm amorphous carbon layer ("aC"), which were deposited onto a silicon substrate by a chemical vapor deposition (CVD) process. The stack was treated with an O2 RIE for 45 seconds to oxidize the SiARC surface. P(Sr-MMA-r-GMA) with thermal acid generators was then cast onto the oxidized SiARC stack, fired at 215 °C for 2 minutes, and rinsed with PGMEA to remove all non-crosslinked material, thus forming a neutral underlayer. A 60 nm thick 193i photoresist (JSR ArF AIM7210JN-8) was then deposited onto the neutral underlayer (labeled "N3" in Fig. 10A), exposed with 193 nm interference lithography, and developed in negative mode with an organic developer (2-heptanone) to create a lattice prestructure with a 100 nm pitch, which allows the fourfold multiplication of the block copolymer with a pitch of 25 nm.

[0151] The photoresist pre-pattern was then transferred into neutral UL / SiARC / HM8500 layers by a series of RIE etchings (4 seconds O2 RIE, 9 seconds CF4 / H2 RIE and 10 seconds O2 RIE), creating an oxidized HM8500 layer at the bottom of the trenches and an etched photoresist as a plateau ( Fig. 10A. 2nd step). The treated substrate was then contacted with a standard aqueous alkaline developer (0.26 N TMAH) for 30 seconds, followed by a rinse with deionized (DI) water to remove the cured photoresist to form a hybrid pre-structure that featured neutral raised surfaces on the plates of the neutral UR / SiARC and recessed stripes containing oxidized HM 8500 material in the trenches ( Fig. 10A, Fig. 3rd step). The side walls had a height H Nof about 0.5 Lo. In this example, stripping the photoresist did not significantly affect the neutral wetting properties of the raised surfaces.

[0152] The corresponding SEM images of Fig. 10B (labeled “3”) shows the topography of the hybrid pre-structure with different widths of W E of the raised surfaces next to the recessed stripes (oxidized HM8500). The wider stripes are the raised surfaces in Fig. 10B wide and in Fig. 10B narrow.

[0153] A 2 wt. % (based on the total solution weight) solution of SA material (PS-b-PMMA block copolymer from Polymer Source, Mn of each block 22k - 22k, 25 nm pitch) in PGMEA was spin-coated onto the hybrid pre-structure at 1,500 rpm for 30 seconds and cured at 255°C for 5 minutes to form a first guided self-assembled structure. After performing a single DSA process, a solvent rinse was performed by pouring PGMEA onto the first DSA structure for 30 seconds and spinning the sample dry to remove all solvent and all or substantially all of the DSA structure. A further spin coating of the PS-b-PMMA block copolymer solution in PMGEA was then performed at 1,500 rpm and the sample was cured at 255 °C for 5 minutes to generate a second DSA structure with fewer defects than the first DSA structure ( Fig. 10A, Fig. (Step 4). The process was repeated for two different widths of WE, designated "wide" and "narrow."

[0154] The PMMA area was removed to display the PS lines ( Fig. 10C, SEM images). Fig. 10 C-wide shows 3 HP lines on each wider raised neutral stripe.

[0155] Fig. 10 C-narrow shows 2 PS lines on each narrower raised neutral stripe.

[0156] Adjustment of the DAS arrays The aligned PS lines above the SiARC were used as an etch mask for the subsequent replacement of the SiARC layer to form the structure of Fig. 10A, Fig. 5th step. The corresponding SEM images show the etched SiARC / HM8500 structure with 3 SiARC / HM 8500 lines ( Fig. 10D wide) or 2 SiARC / HM 8500 lines ( Fig. 10D narrow).

[0157] Although not shown, the etch selectivity of SiARC over HM8500 under O2 RIE gas allows the resulting etched SiARC structure to be used as an etch mask for the HM8500 structure. Depending on the width of the raised surfaces, one or two line cuts can be realized in the HM8500 layer.

[0158] Example 4. DSA on hybrid prestructures produced by a surface modification process

[0159] Silicon substrates were coated with a 50 nm thick organic hard mask (Shinetsu ODL-401) and 10 mm thick SiARC (Shinetsu SHB A-940 L10) to form the formation stack of the hybrid pre-structure. The stack was treated with O2 RIE for 45 seconds to oxidize the SiARC surface. A neutralizing material P(Sr-MMA-r-GMA) containing a thermal acid generator was then cast onto the oxidized SiARC stack, fired at 215 °C for 2 minutes, and rinsed with PGMEA to remove any non-crosslinked material, forming a neutral underlayer.A 60 nm thick 193i photoresist (JSR ArF AIM7210JN-8) was then coated on the neutral layer, pattern-exposed using 193 nm interference lithography, and developed in negative mode with an organic developer (2-heptanone) to create a 224 nm pitch grating pre-pattern, allowing eightfold multiplication for a 28 nm pitch block copolymer (W. E +W R= 8 Lo, Lo = 28 nm). The photoresist pre-pattern was then transferred to the neutral layer and ODL layer through a series of RIE etchings (5 seconds O2 RIE, 7 seconds CF3 / H2 RIE, and 10 seconds O2 RIE), creating an oxidized ODL (organic hard mask) layer at the bottom of the trenches and an etched photoresist on the plateau. The pre-pattern was then placed in contact with a standard aqueous alkaline developer (0.26 N TMAH) for 30 seconds, followed by a DI water rinse and a QZ 3501 rinse (Fuji Film). A solution of a non-neutral surface modification material (AZ Electronic Materials NLD 226, a poly(styrene) brush) was then spin-coated onto the prestructure at 1,500 rpm and fired at 110°C for 5 minutes, followed by a rinse with n-butyl acetate to remove any AZ NLD 226 material without grating formation. The raised surfaces were neutral-wetting after surface modification.The recessed surfaces were non-neutral wetting. The raised surfaces and the recessed surfaces were separated by a height H. N = 0.5 Lo. DSA structures were formed by spin coating an AZ-PME 120 block copolymer solution onto the pre-structure at 1,500 rpm, and the sample was cured at 255 °C for 5 minutes. A short O2 RIE was then applied to partially remove the PMMA region of the DSA structures and increase the contrast between the PMMA and PS regions for SEM characterization.

[0160] Fig. 11A - 11C (SEMs) show good DSA, which can be achieved via the surface-modified hybrid prestructure. When W E ~ 5 Lo (width of the raised neutral stripes on SiARC plates), 5 PS lines were aligned on the raised stripes and 3 PS lines were aligned on the depressed stripes of the surface-modified trenches, Fig. 11A. If WE ∼ 6 Lo, 6 PS lines were aligned to the raised strips and 2 PS lines were aligned to the depressed strips ( Fig. 11B). If W E ~ 4 Lo, 4 PS lines were aligned to the raised strips and 4 PS lines were aligned to the depressed strips ( Fig. 11C).

[0161] Example 5. DSA and pattern transfer onto hybrid pre-structures using a 300 mm diameter wafer and a surface modification process.

[0162] Lithography and stack. A stack with a 5 nm thick silicon oxide layer ("SiO x'The ALD oxide layer (“ODL”) was grown by atomic layer deposition (ALG) on a 50 nm carbon hard mask layer (“ODL”, Shinetsu ODL-410) on a silicon substrate. The ALD oxide layer was coated with a non-neutral material (AZ NLD 201), fired at 250 °C for 2 minutes, and rinsed with PGMEA to remove any non-cross-linked material, thereby forming a neutral underlayer on the ALD oxide layer. The high PS non-neutral underlayer (~75 mol% PS) was chosen to provide a neutral surface on the ALD oxide after the hybrid precursor fabrication process.A 60 nm thick 193i photoresist (Shinetsu X206) was then coated on top of the neutral layer, pattern-wise exposed with a 193i stepper, and negative-mode exposed with n-butyl acetate to create a grating-forming pre-pattern (“X 206”) with a 110 nm pitch, allowing fourfold multiplication for a block copolymer with a 27.5 nm pitch (Fig. Fig. 12, SEMs with numbered process steps, step 1). The patterned photoresist was trimmed, resulting in narrower photoresist lines ( Fig. 12, Fig. 2nd step).

[0163] The photoresist pattern was then transferred to the non-neutral underlayer (NLD 201 layer) using O2 RIE. The treated substrate was then contacted with a standard aqueous alkaline developer (0.26 N TMAH) for 30 seconds, followed by a rinse with deionized water to remove the photoresist ( Fig. 12, Fig.3rd step). The patterned NLD 201 was then used as a mask to etch the ALD oxide using a vapor-phase HF etch (COR) process ( Fig. 12, Fig. 4th step). A solution of a surface modification material (AZ Electronic Materials NLD 226, brush polymer) was then spin-coated onto the pre-structure at 1,500 rpm and fired at 150°C for 2 minutes, followed by rinsing with n-butyl acetate to remove any AZ NLD 226 material without grating formation ( Fig. 12, Fig. 5th step) to form a surface-modified hybrid structure. The raised surfaces (NLD 201 layer after all manufacturing steps) and the recessed surfaces (modified by NLD 226 in the final manufacturing step, brush polymer) were separated by a height of H Nseparated by approximately 0.2 Lo. The raised surfaces were neutrally wetting for the SA material. The modified recessed surfaces and the side walls were non-neutrally wetting for the SA material.

[0164] A PGMEA solution of PS-b-PMMA block copolymer (AZ PME 751, 27.5 nm pitch) for self-assembly was spin-coated onto the surface-modified hybrid structure at 1,500 rpm for 30 seconds and cured at 250 °C for 5 minutes in nitrogen to form a DSA structure. A clean fourfold frequency multiplication was obtained. In this example, a block copolymer application was used. PMMA was removed by an RIE step, leaving well-aligned PS lines. From a group of four PS lines, one PS line was located on the raised stripes (ALD oxide stripes with a neutral surface). The other three PS lines were aligned to the surface-modified ODL stripes in the trenches ( Fig. 12, Fig. 6th step). The PS lines on the ALD oxide stripes are used as the etch masks during the subsequent pattern transfer into the ALD oxide layer and the ODL layer. The adjusted arrays, in which three lines were removed from the original four lines, are shown in Fig. 12, Fig. Step 7, shown. The remaining line is an Oxid / ODL line.

[0165] Examples 6A - 6B. Two-dimensional (2D) matching using DSA on hybrid prestructures produced by surface modification of a patterned photoresist.

[0166] The objectives of the 2D adjustment were a modeled line cutting target (Example 6A, Fig. 13A) and the target “IBM” (Example 6B ( Fig.13B). A central pre-structure is designed to generate the target structures with a 25 nm line pitch. Outside the central structure region, gratings with a pitch of 75 nm (triple multiplication) are used as infill. For these experiments, silicon substrates (“Si wafers”) with 1 µm SiO2 as the top layer (“SiO2”) were used. A 35 nm thick organic hard mask (HM8500) layer (“HM 8500”) was formed on these substrates. A solution containing P(Sr-EDCPMA) was coated on the HM 8500 layer and fired at 200 °C for 3 minutes to form a non-neutral layer. The non-neutral layer provides a preferential wetting surface for PMMA regions in the recessed areas. After this step, a 6 nm HSQ photoresist (“HSQ”) was coated, exposed by e-beam lithography (EBL) and developed in the unexposed area with a standard aqueous alkaline developer (0.26 N TMAH). Fig. 13A photoresist and Fig.13B photoresist are the SEM images of the HSQ structure (cutting mask) after exposure and development. The HSQ photoresist is neutral-wetting for the SA material,

[0167] The hybrid pre-structure was fabricated by surface modification of the HSQ photoresist structure with a neutral brush to generate raised HSQ features with neutral user surfaces as follows. A neutralizing material P(Sr-MMA) brush (0.7% in PGMEA) was coated at 2,000 rpm for 30 seconds and fired at 185 °C for 20 minutes, followed by a PGMEA rinse. The raised surfaces (neutral, brush on HSQ) and the depressed surfaces (non-neutral, containing P(Sr-EDCPMA)) were defined by the height H N= 0.6 Lo. The recessed surfaces may contain neutralizing material, but the amount is insufficient to negatively affect self-assembly. The raised surfaces are neutral to the SA material. The recessed surfaces and sidewalls are non-neutral to the SA material.

[0168] A 2 wt% solution containing 90 / 10 by weight of a PS-b-PMMA block copolymer (22k ​​- 22k, 25 nm pitch) and PMMA (2.5k) was then spin-coated onto the stack at 3,000 rpm for 30 seconds and cured at 260°C for 5 minutes at ambient conditions to form a DSA structure over the hybrid pre-structure. A block copolymer application was used. The PMMA regions of the DSA structure were then etched with O2 RIE, revealing the block copolymer regions and the underlying structure. Fig. 13A-DSA and Fig.13B DSA images show well-aligned PS gratings overlying the recessed and raised surfaces of the hybrid precursors. The PS lines were then used as an etch mask to pattern the HSQ layer and the HM8500 layer by performing a carefully timed CFR4 RIE followed by O2 RIE. Fig. 13A adjustment and Fig. Figure 13B shows the SEM images of the adjusted DSA arrays as target structures.

[0169] Example 6C. Two-dimensional fitting using DSA on a hybrid prestructure produced by a filling process.

[0170] A target structure with a long single-line taper consisting of a combination of three lines alternating with a three-line spacing is in Fig.13C target shown. This structure is designed to accommodate DSA arrays with a 28 nm pitch and is repeated over an area of ​​approximately 8.5 µm × 5.8 µm. The hybrid pre-structure was fabricated using a fill-in process. Silicon substrates ("Si wafers") were coated with a 50 nm thick organic hard mask ("ODL", Shinetsu ODL401) and 10 mm thick SiARC (Shinetsu SHB A-940 L10, "SiARC") to form the formation stack of the hybrid pre-structure. The stack was treated with O2 RIE for 50 seconds to oxidize the SiARC surface. A neutralization material P(Sr-MMA-r-GMA) containing a thermal acid generator was then cast onto the oxidized SiARC stack, fired at 215 °C for 2 minutes, and rinsed with PGMEA to remove any non-crosslinked material, forming a neutral underlayer.A 60 nm thick 193i photoresist (JSR ArF AIM7210JN-8) was then coated onto the neutral underlayer, patterned by e-beam lithography (EBL), and developed in negative mode with an organic developer (2-heptanone). Fig. 13C photoresist shows the AIM7210 photoresist structure (“7210”).

[0171] The photoresist pattern was then transferred to the substrate through a series of RIE etchings (5 seconds O2 RIE, 11 seconds CF4 RIE, and 10 seconds O2 RIE). A polarity change / curing process was initiated by exposing the photoresist pattern to a deep DUV broadband light from a Hg / X3 500 W short-arc lamp (UXM-501MA-Ushio America) with a total flood exposure dose of 60 mJ / cm 2, followed by a hard bake at 95 °C for 60 seconds and at 200 °C for 180 seconds. After curing the photoresist, a non-neutral filler material P(Sr-EDCPMA) containing a thermal acid generator was then cast onto the cured photoresist structures and fired at 200 °C for 3 minutes. The concentration and spin rate of the filler material were then adjusted to avoid filling the trenches up to the photoresist features (i.e., the top surface of the filler material was below the bottom interface of the photoresist feature and the neutral layer). In this case, a 0.2% solution was spin-cast at 4,000 rpm. The filled photoresist pattern was then brought into contact with a standard aqueous alkaline developer (0.26 N TMAH) for 60 seconds, followed by rinsing with deionized water to remove the cured photoresist pattern and form neutral raised surfaces.The raised surfaces (neutralization material) and the depressed surfaces (filling material) were separated by a height H. N = 0.5 Lo. The raised surfaces are neutral for the SA material. The recessed surfaces and sidewalls are non-neutral for the SA material.

[0172] The PS-b-PMMA block copolymer solution (AZ PME 120, 28 nm pitch) was then spin-coated onto the filled pre-structure at 1,500 rpm for self-assembly, and the sample was then cured at 255 °C for 5 minutes to form the first DSA structure. After performing a single DSA process, a solvent rinse was performed by pouring PGMEA onto the first DSA structure for 30 seconds and spinning the sample dry to remove all the solvent and all or substantially all of the DSA structure. Another spin-coating of AZ PME 120 was then performed at 1,500 rpm, and the sample was cured at 255 °C for 10 minutes to generate second DSA structures with fewer defects than those of the first DSA structures. The DSA structures were then etched to remove the PMMA regions using O2 RIE, resulting in a PS line structure ( Fig.13 C-DSA, SEM). The PS lines were then used as an etch mask to pattern the SiARC layer and HM8500 by performing a carefully timed CFR4 RIE followed by O2 RIE. Fig. Figure 13A shows the SEM images of the adjusted DSA arrays as target structures. conclusion

[0173] The examples demonstrate that a neutral surface can retain neutral wetting properties with respect to a selected SA material when the neutral surface is subjected to a process that involves forming a photoresist pattern on the neutral surface, transferring the photoresist pattern to the underlying layers, and peeling the photoresist pattern from the neutral surface.

[0174] The examples further demonstrate that, with respect to a particular SA material, a photoresist pattern can be removed without negatively affecting the desired surface properties of the recessed surfaces and sidewalls.

[0175] The examples also demonstrate that the depressed surfaces of a topographical structure can be subjected to surface modification and / or filling to have non-neutral surface properties for a given SA material without negatively affecting the neutral surface properties of the raised surfaces.

[0176] The examples further demonstrate that the raised surfaces of a topographical structure can be surface modified to have neutral surface properties for a particular SA material without negatively affecting the non-neutral surface properties of the sidewalls.

[0177] The examples also demonstrate that the neutral and non-neutral surface modification materials can be applied before or after the formation of the patterned photoresist features. Preferably, one is applied before the photoresist is applied, and the other is applied after the photoresist is applied.

[0178] Using the techniques described above, hybrid precursors for self-assembly of a block copolymer were fabricated. These precursors feature neutral raised surfaces with underlying materials with high etch resistance and recessed surfaces with underlying materials with lower etch resistance. By correctly specifying the dimensions of the precursor using the above guidelines, unidirectional, perpendicularly aligned lamellae were formed on the raised surfaces and, in some cases, over the recessed surfaces. Transferring the domain structures to the underlying layers resulted in sophisticated, matched structures in the underlying layers.

Claims

[1] A method which comprises: i) forming a layer (21), hereinafter referred to as SA layer, which comprises a material for self-assembly, hereinafter referred to as SA material, on an upper surface of a hybrid prestructure and forming a cover layer (174) arranged on an upper surface of the SA layer (21), wherein the SA material is designed for self-assembly to form a phase-separated lamellar region structure (31) with a characteristic pitch Lo, the pre-structure is arranged on a substrate (60), the upper surface (13) of the pre-structure has a geometric main axis, the upper surface of the pre-structure has a) independent raised surfaces (13) interspersed with adjacent recessed surfaces (14) and b) side walls (18) connecting the raised surfaces (13) to the recessed surfaces (14), the material lying under the raised surfaces (13) of the pre-structure has a higher etching resistance in a particular etching process compared to the material lying under the recessed surfaces (14) of the pre-structure, a certain raised surface (13) a width W E which is defined as the length of the particular raised surface (13) in a direction perpendicular to the main axis, a certain recessed surface (14) a width W R which is defined as the length of the recessed surface (14) in a direction perpendicular to the main axis, W R +W E for each pair of adjacent recessed and raised surfaces (13, 14) is an independent sum with the value of about nLo, where n is an integer from 4 to about 30, W R of at least one of the recessed surfaces (14) is greater than about 2 Lo, W Eof at least one of the raised surfaces (13) is greater than about 2 Lo, each of the side walls (18) has an independent height H N from about 0.1 Lo to about 2 Lo, the SA layer (21) is in contact with the raised surfaces (13), the recessed surfaces (14) and the side walls (18) of the prestructure, and the SA layer (21) has an upper surface in contact with the top coating; ii) enabling or inducing self-organization of the SA material, thereby forming a self-organized SA layer (21) having the lamellar domain structure, wherein the domain structure comprises alternating regions (32, 33) each comprising chemically different components of the SA material, each of the regions comprising a plurality of lamellae, wherein the raised surfaces (13) are neutral-wetting for the areas (32,33), each of the raised surfaces (13) touches at least one of the slats of each of the regions (32, 33), each of the lamellae in contact with a given raised surface (13) of the pre-structure is a) oriented perpendicular to the given raised surface (13), b) in contact with the covering layer above the given raised surface (13), and c) oriented along the main axis of the pre-structure. iii) selectively removing one of the regions (32, 33) by means of an etching process, thereby forming an etched region structure comprising the lamellae of a remaining region; and iv) selectively transferring the etched region structure into the material having a higher etch resistance beneath the raised surfaces (13) using a second etching process, thereby forming a transfer structure having topographical features comprising material having a higher etch resistance. [2] The method of claim 1, wherein the method includes selectively transferring the transfer structure into one or more underlying layers of the substrate (60) using a third etch process, thereby forming a second transfer structure. [3] The method of claim 1 or claim 2, wherein the sidewalls (18) are in contact with a portion of the self-assembled SA layer (21). [4] The method of claim 1 or claim 2, wherein the lower surfaces (14) are in contact with a portion of the self-assembled SA layer (21). [5] The method of claim 1 or claim 2, wherein the sidewalls (18) are non-neutral wetting for the regions of the self-assembled SA layer (21). [6] The method of claim 1 or claim 2, wherein the sidewalls (18) and recessed surfaces (14) are non-neutral wetting for the regions of the self-assembled SA layer (21). [7] The method according to any one of the preceding claims, wherein regions of the self-assembled SA layer (21) overlying the respective underlying recessed surfaces (14) of the pre-structure comprise lamellae oriented perpendicular to the respective underlying recessed surfaces (14). [8] The method of any preceding claim, wherein the etched region structure is a unidirectional line spacing structure having a pitch of approximately Lo. [9] A method according to any one of the preceding claims, wherein the SA material comprises a block copolymer. [10] The process according to any one of the preceding claims, wherein the block copolymer is a poly(styrene-B-methyl methacrylate) block polymer. [11] The method of claim 1, wherein the upper surface (13) of the pre-structure comprises two or more regions having recessed surfaces (14) with different values of WR. [12] The method of claim 1, wherein the upper surface (13) of the pre-structure comprises two or more regions having recessed surfaces (14) with different values of WE. [13] The method of claim 1, wherein the upper surface (13) of the pre-structure has two or more regions with different values of WE + WR for a given pair of adjacent raised and depressed surfaces (14). [14] The method of claim 12, wherein the two or more regions (32, 33) extend along the main axis of the pre-structure. [15] The method of claim 1, wherein the material under the raised surfaces (13) comprises an inorganic material. [16] The method of claim 1, wherein the material under the raised surfaces (13) comprises a photoresist. [17] The method of claim 16, wherein the photoresist is a silsesquioxane. [18] The method according to claim 1, wherein the self-assembly of the SA layer (21) forms a cover layer arranged on the SA layer (21). [19] The method of claim 1, wherein HN is about 0.2 Lo to about 2 Lo. [20] A layered structure that has: a hybrid pre-structure arranged on the substrate (60), the pre-structure having an upper surface (139) with a geometric main axis; wherein the layered structure is suitable for forming a semiconductor device by guided self-organization of a specific self-organization layer, hereinafter referred to as a specific SA layer, arranged on the upper surface (13) of the pre-structure, wherein the specific SA layer (21) has an upper surface in contact with a cover layer, and the SA layer (21) comprises a specific self-organization material, hereinafter referred to as a specific SA material, which is designed to form a phase-separated lamellar region structure with a characteristic pitch Lo, the upper surface (13) of the pre-structure has a) independent raised surfaces interspersed with adjacent recessed surfaces (14) and b) side walls (18) connecting the raised surfaces to the recessed surfaces, the material lying beneath the raised surfaces (13) of the pre-structure has a higher etching resistance in a given etching process than the material lying beneath the recessed surfaces (14) of the pre-structure, a certain raised surface (13) a width W E which is defined as the length of the particular raised surface (13) in a direction perpendicular to the main axis, a certain adjacent recessed surface (14) has a width W R which is defined as the length of the recessed surface in a direction perpendicular to the main axis, W R +W E for each pair of adjacent depressed and raised surfaces (13, 14) is an independent sum having a value of approximately an integer multiple of Lo, the integer being between 4 to approximately 30, W R of at least one of the recessed surfaces (14) is greater than about 2 Lo, WE of at least one of the recessed surfaces (13) is greater than about 2 Lo, and each of the side walls (18) independently has a height H N from about 0.1 Lo to about 2 Lo, the region structure formed by the specific SA layer has alternating lamellar regions, each of which has chemically different components of the specific SA material, each of the regions (32, 33) having a plurality of lamellae, the raised surfaces being neutral-wetting for the regions of the self-assembled specific SA layer (21), each of the raised surfaces (13) being in contact with at least one of the lamellae of each of the regions of the self-assembled specific SA layer (21), each of the lamellae in contact with a specific raised surface (13) of the pre-structure a) being oriented perpendicular to the specific raised surface, b) being in contact with the cover layer above the specific raised surface, and c) being oriented along the major axis of the pre-structure. [21] The layered structure according to claim 20, wherein the substrate comprises a silicon wafer or a metal foil as a first layer, hereinafter called bottom layer, of the substrate (60). [22] The layered structure of claim 20, wherein the substrate (60) comprises one or more layers comprising materials selected from the group consisting of silicon nitrides, carbon film, spin-on carbon, silicon oxide, metal oxides, anti-reflective materials, and combinations thereof disposed on the bottom layer. [23] A method for forming a hybrid pre-structure comprising: Selecting a self-assembly material, hereinafter referred to as SA material, which is designed for self-assembly to form a phase-separated lamellar domain structure having lamellar domains (32, 33) with a characteristic pitch Lo; Forming an underlayer disposed on a substrate (60); Forming a topographical photoresist structure disposed on the underlayer, the photoresist structure comprising photoresist features separated by trenches having bottom surfaces comprising material of the underlayer; selectively removing material beneath the bottom surfaces of the trenches, thereby forming a second topographical structure, the second topographical structure comprising trenches having a bottom surface comprising material of the substrate; Removing the photoresist structure from the second topographic structure, thereby forming the hybrid pre-structure; wherein the hybrid prestructure has an upper surface (13) and a geometric main axis on the upper surface (13), the upper surface (13) of the pre-structure a) has independent raised surfaces comprising an underlayer material interspersed with adjacent recessed surfaces (14) comprising substrate material, and b) side walls (18) connecting the raised surfaces (18) to the recessed surfaces (14), the raised surfaces (13) are neutral-wetting for the areas, the recessed surfaces (14) and side walls (18) are non-neutral wetting for the areas, the material lying beneath the raised surfaces (13) of the pre-structure has a higher etching resistance in a given etching process than the material lying beneath the recessed surfaces (14) of the pre-structure, raised surfaces (13) of the pre-structure an independent width W E which is defined as the length of the particular raised surface (13) in a direction perpendicular to the main axis, recessed surfaces (14) of the pre-structure independent widths W R which is defined as the length of the recessed surface (14) in a direction perpendicular to the main axis, W R +W E for a given pair of adjacent raised and depressed surfaces (13, 14) is an independent sum having a value which is approximately an integer multiple of Lo, the integer being between 4 to about 30, W E of at least one of the raised surfaces (13) is greater than about 2 Lo, W R of at least one of the recessed surfaces (14) is greater than about 2 Lo, the side walls (18) have a height H N from about 0.1 Lo to about 2 Lo, and a self-assembly layer (21), hereinafter referred to as SA layer, comprising the SA material arranged on the upper surface (13) of the pre-structure and having an upper surface in contact with an atmospheric interface and / or a cover layer, is designed for self-assembly to form the lamellar region structure, wherein the region structure has alternating regions each comprising chemically different components of the SA material, wherein each of the regions (32, 33) has a plurality of lamellae, wherein each of the raised surfaces is in contact with at least one of the lamellae of each of the regions, and each of the lamellae in contact with a specific raised surface (13) of the pre-structure a) is oriented perpendicular to the specific raised surface, b) is in contact with an atmospheric interface above the specific raised surface (13),and c) is aligned along the main axis of the pre-structure, and wherein the underlayer is non-neutral-wetting for the regions. [24] The method of claim 23, comprising filling the trenches of the second topographical structure with a filler material to a level below the bottom surface of the underlayer prior to removing the photoresist structure, wherein the filler material is non-neutral wetting for the regions of the self-assembled SA material. [25] The method of claim 23, comprising surface modification of the second topographical structure with a material that is non-neutral wetting for the areas prior to removal of the photoresist structure. [26] The method of claim 23, wherein removing the photoresist pattern forms a third topographical pattern, and the method comprises treating the third topographical pattern with a surface modifier, thereby forming a hybrid pre-pattern, wherein the raised surfaces and / or depressed surfaces of the hybrid pre-pattern comprise the surface modifier. [27] A method for forming a hybrid pre-structure comprising: Selecting a self-assembly material, hereinafter referred to as SA material, which is designed to self-assemble to form a phase-separated lamellar domain structure having lamellar domains with a characteristic pitch Lo; Forming an underlayer disposed on a substrate (60), the underlayer being non-neutral wetting for the regions; forming a topographical photoresist structure disposed on the underlayer, the photoresist structure comprising photoresist features separated by trenches with bottom surfaces comprising underlayer material; Treating the upper surfaces of the photoresist features with a material that is neutral-wetting for the regions, hereinafter referred to as neutralization material, thereby forming the hybrid pre-structure; wherein the prestructure has an upper surface (13) and a geometric main axis on the upper surface, the upper surface of the pre-structure a) has independent raised surfaces (13) comprising a photoresist and a neutralizing material interspersed with adjacent recessed surfaces (14) comprising underlayer material, b) side walls (18) connecting the raised surfaces (13) to the recessed surfaces (14), the raised surfaces (13) for the areas are neutral-wetting, the recessed surfaces (14) and side walls (18) for the areas are non-neutral wetting, the material lying under the raised surfaces (13) of the pre-structure has a higher etching resistance in a specific etching process than the material lying under the recessed surfaces (14) of the pre-structure, raised surfaces (13) of the pre-structure have an independent width W E which is defined as the length of the given raised surface in a direction perpendicular to the main axis, recessed surfaces (14) of the pre-structure independent widths W R which are defined as the length of the recessed surface (14) in a direction perpendicular to the main axis, W R +W E for a given pair of adjacent raised and depressed surfaces (13, 14) is an independent sum having a value which is approximately an integer multiple of Lo, the integer being between 4 to about 30, W E of at least one of the raised surfaces (13) is greater than about 2 Lo, W R of at least one of the recessed surfaces (14) is greater than about 2 Lo, the side walls (18) have a height H N from about 0.1 Lo to about 2 Lo, a self-assembly layer (21), hereinafter referred to as SA layer, comprising the specific SA material arranged on the upper surface (13) of the pre-structure and having an upper surface in contact with an atmospheric interface, designed for self-assembly to form the lamellar domain structure, wherein the domain structure comprises alternating regions (32, 33) each comprising chemically different components of the SA material, wherein each of the regions (32, 33) comprises a plurality of lamellae, wherein each of the raised surfaces (13) is in contact with at least one of the lamellae of each of the regions (32, 33), and each of the lamellae in contact with a specific raised surface (13) of the pre-structure a) is oriented perpendicular to the specific raised surface (13), b) is in contact with an atmospheric interface above the specific raised surface (13),and c) is aligned along the main axis of the pre-structure., [28] The method of claim 27, wherein the topographical photoresist pattern comprises a silsesquioxane photoresist. [29] The method of claim 27 or claim 28, wherein the recessed surfaces (14) of the pre-structure comprise a residual neutralizing material.

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