Pattern forming method
By forming a guiding layer and self-assembling block copolymers on a substrate, the problem of insufficient block arrangement in DSA technology is solved, achieving high-quality patterning and deep etching effects, which is suitable for semiconductor device manufacturing.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- RUILI INTEGRATED CIRCUIT CO LTD
- Filing Date
- 2024-11-11
- Publication Date
- 2026-05-15
AI Technical Summary
Directed self-assembly (DSA) technology for block copolymers suffers from weak intermolecular forces, resulting in insufficient block arrangement and order, which affects the quality of pattern formation.
After forming a mask layer and an anti-reflection layer on a substrate, the anti-reflection layer is patterned to form trenches, and a first guiding layer is filled in the trenches. Subsequently, a block copolymer layer of block copolymer and a second guiding layer are formed on the guiding layer to allow them to self-assemble and form alternating block domains. Unwanted portions are removed by etching to form the target pattern.
It improves the orderliness of the block copolymer arrangement, ensures the quality of pattern formation, and increases the etching depth of the substrate pattern, making it suitable for the manufacture of highly integrated semiconductor chips.
Smart Images
Figure CN122054926A_ABST
Abstract
Description
Technical Field
[0001] This disclosure relates to the semiconductor field, and more particularly to a method for forming patterns. Background Technology
[0002] Directed self-assembly (DSA) of block copolymers utilizes block copolymers obtained by polymerizing two or more chemically dissimilar monomers. Nanoscale patterns are formed through microphase separation between different blocks, creating pattern conversion templates for the fabrication of related semiconductor devices. Compared to traditional photolithography, DSA eliminates the need for light sources and masks, enabling the generation of large-scale ordered patterns and offering advantages such as low cost, high resolution, and high throughput. However, because DSA relies on intermolecular forces (chemical potential energy), these forces are relatively weak, resulting in insufficient molecular binding and orientation strength. This ultimately affects the arrangement and degree of order of the two blocks. Therefore, it is necessary to propose a new method for pattern formation. Summary of the Invention
[0003] According to some embodiments of this disclosure, this disclosure provides a method for forming a pattern, characterized in that it includes:
[0004] Provide substrate;
[0005] A mask layer and an anti-reflection layer are sequentially formed on the substrate;
[0006] The antireflective layer is patterned to form a first trench, the first trench exposing a portion of the mask layer;
[0007] A first guiding layer is formed in the first trench, and the first guiding layer fills the first trench;
[0008] A block copolymer layer and a second guiding layer formed of block copolymers are sequentially formed on the first guiding layer and the patterned antireflective layer, and the block copolymers are self-assembled to form a first block domain and a second block domain formed of the first block and the second block of the block copolymers, respectively, wherein the first block domain and the second block domain are alternately and repeatedly arranged on the first guiding layer.
[0009] The second guide layer and the second segment domain are etched away, while the first segment domain is retained to form the target pattern.
[0010] In some embodiments, the materials of both the first guiding layer and the second guiding layer comprise a random copolymer of styrene and methyl methacrylate.
[0011] In some embodiments, the thickness of the first guiding layer is greater than or equal to the thickness of the second guiding layer in a direction perpendicular to the substrate.
[0012] In some embodiments, the thickness of the block copolymer layer is greater than the thickness of the first guiding layer along a direction perpendicular to the substrate.
[0013] In some embodiments, before forming the first guiding layer within the first trench, the method further includes:
[0014] The patterned antireflective layer is then surface modified.
[0015] In some embodiments, the surface-modifying gas includes fluorinated hydrocarbons.
[0016] In some embodiments, after forming a first guiding layer in the first trench, the method further includes: performing a first annealing process on the first guiding layer, wherein the temperature range of the first annealing process is 180-250°C and the time range is 5-20 min.
[0017] In some embodiments, the method further includes performing a second annealing process after sequentially forming the block copolymer layer and the second guiding layer formed by the block copolymer on the first guiding layer and the patterned antireflective layer, so that the block copolymer can self-assemble, wherein the temperature range of the second annealing process is 180-270°C and the time range is 10-120 min.
[0018] In some embodiments, the etching selectivity ratio of the second segment to the first segment ranges from 2:1 to 5:1, and the etching selectivity ratio of the second segment to the first guide layer or the second guide layer ranges from 1:1 to 3:1.
[0019] In some embodiments, after etching away the second guiding layer and the second segment region while retaining the first segment region to form the target pattern, the method further includes: using the target pattern as a mask to pattern the mask layer; and using the patterned mask layer as a mask to pattern the substrate.
[0020] The technical solution provided by the embodiments of this disclosure has at least the following advantages: After forming a block copolymer layer and a second guiding layer formed of block copolymers sequentially on the first guiding layer, the block copolymer layer undergoes self-assembly to form a first block domain and a second block domain formed of the first block and the second block of the block copolymer, respectively. The first block domain and the second block domain are alternately and repeatedly arranged on the first guiding layer. By forming a block copolymer layer between the first guiding layer and the second guiding layer and allowing it to self-assemble, the orderliness of the arrangement of the first block and the second block can be effectively improved, ensuring the quality of pattern formation. Attached Figure Description
[0021] One or more embodiments are illustrated by way of example with corresponding pictures in the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Unless otherwise stated, the pictures in the accompanying drawings do not constitute a limitation on scale. In order to more clearly illustrate the technical solutions in the embodiments of this disclosure or the conventional technology, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0022] Figure 1 This is a flowchart illustrating the steps of a method for forming a pattern according to an embodiment of the present disclosure.
[0023] Figures 2 to 10 This is a schematic diagram of the structure corresponding to each step of a method for forming a pattern according to an embodiment of the present disclosure. Detailed Implementation
[0024] The embodiments of this disclosure will now be described in detail with reference to the accompanying drawings. However, those skilled in the art will understand that many technical details have been provided in the embodiments of this disclosure to facilitate a better understanding of the disclosure. However, the technical solutions claimed in this disclosure can be implemented even without these technical details and various variations and modifications based on the following embodiments.
[0025] Guided by Moore's Law, the feature size of components in integrated circuits continues to shrink, and corresponding patterning technologies have also developed and evolved. Extreme ultraviolet (EUVL) patterning, as a next-generation patterning technology, still faces challenges in large-scale semiconductor manufacturing due to its high cost and limited production volume. Directed self-assembly (DSA) of block copolymers is a novel patterning method that has attracted widespread attention from academia and industry due to its high resolution and extremely low cost.
[0026] Directed self-assembly (DSA) of block copolymers is a cutting-edge nanofabrication technology. It utilizes block copolymers obtained by polymerizing two or more chemically dissimilar monomers. Under conditions such as thermal annealing, microphase separation between different blocks spontaneously forms ordered nanoscale patterns, which can then be used as pattern transfer templates for semiconductor device fabrication. Compared to traditional photolithography, DSA eliminates the need for light sources and masks, enabling the generation of large-scale ordered patterns. It offers significant advantages such as low cost, high resolution, and high throughput, thus demonstrating immense potential in the semiconductor industry, particularly in the manufacture of high-density memory and advanced logic chips. However, because DSA relies on intermolecular forces (chemical potential energy), these forces are relatively weak, resulting in insufficient molecular binding and orientation strength. This ultimately affects the arrangement and degree of order of the two blocks. Therefore, it is necessary to propose a new method for pattern formation.
[0027] To address the aforementioned technical problems, this disclosure provides a method for forming a pattern. The method for forming a pattern provided by this disclosure will be described below with reference to the accompanying drawings.
[0028] Figure 1 A flowchart illustrating the steps of a method for forming a pattern according to an embodiment of this disclosure; Figures 2 to 10 This is a schematic diagram showing the structural steps of a pattern-forming method according to an embodiment of the present disclosure. The pattern-forming method provided in this embodiment will be described in detail below with reference to the accompanying drawings.
[0029] Step S100 provides substrate 101; in some embodiments, reference is made to... Figures 1-2 The substrate 101 can be made of single-crystal silicon (Si), single-crystal germanium (Ge), or silicon-germanium (GeSi), silicon carbide (SiC); it can also be silicon-on-insulator (SOI), germanium-on-insulator (GOI); or it can be other materials, such as gallium arsenide or other group III-V compounds. In another embodiment, the substrate 101 may also include semiconductor materials, metals, dielectrics, dopants, and other materials commonly used in semiconductor substrates.
[0030] In step S200, a mask layer 102 and an anti-reflection layer 103 are sequentially formed on the substrate 101. Exemplarily, the material of the mask layer 102 can be silicon nitride (SiN) or silicon oxynitride (SiON), and it can be deposited on the substrate 101 using chemical vapor deposition (CVD), plasma-enhanced chemical vapor deposition (PECVD), or atomic layer deposition (ALD) processes.
[0031] In step S300, the anti-reflective layer 103 is patterned to form a first trench 105, which exposes a portion of the mask layer 102.
[0032] In some embodiments, reference Figures 2-4 The patterning of the antireflective layer 103 to form the first trench 105 may include forming a photoresist layer 104 on the antireflective layer 103, patterning the photoresist layer 104, and etching the antireflective layer with the patterned photoresist layer 104 to form the patterned antireflective layer 103. The patterned antireflective layer 103 has a first trench 105 formed in it, and the first trench 105 exposes a portion of the mask layer 102.
[0033] In step S400, a first guiding layer 106 is formed in the first trench 105, and the first guiding layer 106 fills the first trench 105.
[0034] Specifically, in some embodiments, the material of the first guiding layer 106 may include a random copolymer of styrene (PS) and methyl methacrylate (PMMA). Reference Figure 4 and Figure 5In order to form the first guiding layer 106, one or more random copolymer materials, such as copolymer materials including styrene (PS) blocks and methyl methacrylate (PMMA) blocks, are first dissolved in a solvent to form a mixed solution for forming the first guiding layer 106. Exemplarily, the mixed solution can be coated onto the exposed mask layer 102 and the sidewalls of the first trench 105 by spin coating to form a first guiding layer 106. The solvent for dissolving the copolymer material containing styrene (PS) blocks and methyl methacrylate (PMMA) blocks can include, for example, glycol ether derivatives such as ethyl cellosolve, methyl cellosolve, propylene glycol monomethyl ether (PGME), diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, dipropylene glycol dimethyl ether, propylene glycol n-propyl ether, or diethylene glycol dimethyl ether; glycol ether ester derivatives such as ethyl cellosolve acetate, methyl cellosolve acetate, propylene glycol monomethyl ether acetate (PGMEA), etc.; carboxylic acid esters such as ethyl acetate, n-butyl acetate, and amyl acetate; and carboxylic acid esters of diacids such as diethyl oxalate and dimethyl malonic acid. Ethyl esters; dicarboxylic acid esters of diols such as ethylene glycol diacetate and propylene glycol diacetate; hydroxycarboxylic acid esters such as methyl lactate, ethyl lactate (EL), ethyl glycolate and ethyl-3-hydroxypropionate; ketone esters such as methyl pyruvate or ethyl pyruvate; alkoxycarboxylic acid esters such as methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, ethyl 2-hydroxy-2-methylpropionate or methyl ethoxypropionate; ketone derivatives such as methyl ethyl ketone, acetylacetone, cyclopentanone, cyclohexanone or 2-heptanone; ketone ether derivatives such as diacetone alcohol methyl ether; ketone alcohol derivatives such as acetone alcohol or diacetone alcohol; ketals or acetals such as 1,3-dioxalane and diethoxypropane; lactones such as butyrolactone; amide derivatives such as dimethylacetamide or dimethylformamide, anisole and mixtures thereof.
[0035] In some embodiments, before forming the first guiding layer 106 within the first trench 105, the method further includes: surface modification of the patterned antireflective layer 103. Specifically, the sidewalls and top surface of the patterned antireflective layer 103 may be surface modified, wherein the surface modification gas may include oxygen (O2), argon (Ar), or a fluorinated hydrocarbon (C). x H y F z For example, the surface-modifying gas can be a fluorinated hydrocarbon (C). x H y F zThe material in the antireflective layer 103 can be modified to a polar material including fluorine groups, thereby enhancing the polarity of the antireflective layer 103. For example, the material of the antireflective layer 103 can be formed of a material capable of bonding with hydroxyl (-OH) groups in the first guiding layer 106. For instance, the material of the antireflective layer 103 can be a polystyrene derivative containing the structural formula (1), and the specific reaction can be referred to reaction formula (1):
[0036]
[0037] The material of the modified antireflective layer 103 is shown in structural formula (2), wherein at least one of the groups R1, R2, R3, R4, R5, R6 is a fluorine (F) atom, and the remaining groups can be hydrogen (H) atoms. For example, R1 is a hydrogen (H) atom, and R2, R3, R4, R5, R6 are fluorine (F) atoms, or R1, R2 are hydrogen (H) atoms, and R3, R4, R5, R6 are fluorine (F) atoms, which is not limited here.
[0038] In other embodiments, the material of the antireflective layer 103 may be a polystyrene derivative including structural formula (3), structural formula (4) or structural formula (5). The material of the antireflective layer 103 in reaction formula (1) may also be one of the polystyrene derivatives including structural formula (3), structural formula (4) or structural formula (5), which is not limited here. The specific structural formulas of the polystyrene derivatives including structural formula (3), structural formula (4) or structural formula (5) are as follows:
[0039]
[0040]
[0041] Since the material of the first guiding layer 106 includes a copolymer material containing styrene (PS) blocks and methyl methacrylate (PMMA) blocks with terminal hydroxyl groups (-OH groups), when the surface-modifying gas is a fluorine-containing hydrocarbon (CxHyFz), the sidewalls and top surface of the antireflective layer 103 can be modified to have fluorine (F)-doped polar groups, which helps the antireflective layer 103 to bond / join with the mixed solution forming the first guiding layer 106, thereby improving the coating effect of the first guiding layer 106. Meanwhile, since the top surface of the final anti-reflective layer 103 is higher than the top surface of the first guiding layer 106, during the formation of the first guiding layer 106, the thickness of the first guiding layer 106 located on the top surface of the anti-reflective layer 103 is less than the thickness of the first guiding layer 106 located in the first trench 105. Therefore, the first guiding layer 106 covering the top surface of the anti-reflective layer 103 can be removed by solvent cleaning, thus retaining only the first guiding layer 106 located in the first trench 105, that is, only retaining the first guiding layer 106 covering the sidewall of the first trench 105. The cleaning solution can be 70% propylene glycol methyl ether (PGME, chemical formula C4H). 10 O2) and 30% propylene glycol methyl ether acetate (PGMEA, chemical formula C6H) 12 The O3 mixture solution can be baked at 100-150℃ for 1-5 minutes after cleaning to remove the cleaning solution.
[0042] In some embodiments, after forming the first guiding layer 106 in the first trench 105, the process further includes: performing a first annealing process on the first guiding layer 106. The temperature range of the first annealing process can be 180-250°C, and the annealing time range can be 5-20 minutes, so that the random copolymer in the first guiding layer 106 undergoes self-assembly to guide the subsequent block copolymer layer to self-assemble. The process of cleaning and drying the surfaces of the formed first guiding layer 106 and the antireflective layer 103 to remove the first guiding layer 106 from the surface of the antireflective layer 103 can be performed after the first annealing process.
[0043] S500 A block copolymer layer 107 and a second guide layer 108 formed of block copolymers are sequentially formed on the first guide layer 106 and the patterned antireflective layer 103, and the block copolymers are self-assembled to form a first block domain 109 and a second block domain 110 formed of the first block and the second block of the block copolymer, respectively, wherein the first block domain 109 and the second block domain 110 are alternately and repeatedly arranged on the first guide layer 106.
[0044] refer to Figures 6-7A block copolymer layer 107, formed of block copolymers, is formed on the first guiding layer 106 and the patterned antireflective layer 103. The block copolymers can be spin-coated onto the first guiding layer 106 and the antireflective layer 103 to form the block copolymer layer 107. The block copolymers may include the following materials: polybutadiene-polybutyl methacrylate block copolymer, polybutadiene-polydimethylsiloxane block copolymer, polybutadiene-polymethyl methacrylate block copolymer, polybutadiene-polyvinylpyridine block copolymer, polybutyl acrylate-polymethyl methacrylate block copolymer, polybutyl acrylate-polyvinylpyridine block copolymer, polyisoprene-polyvinylpyridine block copolymer, polyisoprene-polymethyl methacrylate block copolymer, polyhexyl acrylate-polyvinylpyridine block copolymer, polyisobutylene-polybutyl methacrylate block copolymer, polyisobutylene-polymethyl ... Poly(isobutylene)-poly(butyl methacrylate) block copolymer, poly(isobutylene)-poly(dimethylsiloxane) block copolymer, poly(butyl methacrylate)-poly(butyl methacrylate) block copolymer, poly(ethylene ethyl)-poly(methyl methacrylate) block copolymer, polystyrene-poly(butyl methacrylate) block copolymer, polystyrene-poly(butadiene) block copolymer, polystyrene-poly(isoprene) block copolymer, polystyrene-poly(dimethylsiloxane) block copolymer, polystyrene-poly(polyvinylpyridine) block copolymer, poly(ethylene ethyl)-poly(polyvinylpyridine) block copolymer, polyethylene-poly(polyvinylpyridine) block copolymer, polyethylene-poly(dimethylsiloxane) block copolymer, or polystyrene-poly(ethylene oxide) block copolymer. For example, the blocks of a block copolymer (e.g., a first block and a second block) can each have different chemical properties, with one block being relatively more hydrophobic (e.g., repelling water) and the other relatively more hydrophilic (attracting water). Specifically, one block can be relatively more similar to oil, and the other block can be relatively more similar to water. Such differences in chemical properties between different polymer blocks, i.e., hydrophilic-hydrophobic differences or other differences, can cause the block copolymer molecules to self-assemble. For example, self-assembly can be based on microphase separation between polymer blocks. Conceptually, this can be analogous to the phase separation of generally immiscible oils and water. Similarly, differences in hydrophilicity between polymer blocks (e.g., one block is relatively hydrophobic and the other block is relatively hydrophilic) can lead to a substantially similar microphase separation, in which different polymer blocks will attempt to “separate” from each other due to chemical repulsion with other blocks.
[0045] A second guiding layer 108 is formed on the first guiding layer 106 and the patterned antireflective layer 103, covering the block copolymer layer 107. The forming process may include spin coating. The second guiding layer 108 may be formed from a material layer that exhibits similar affinity values to all polymer blocks of the block copolymer layer 107. For example, the second guiding layer 108 may include a random copolymer material comprising a first block and a second block that have been randomly copolymerized. When the block copolymer includes polystyrene (PS) and polymethyl methacrylate (PMMA) block copolymer materials, i.e., the first block is a styrene polymer (PS) segment and the second block is a polymethyl methacrylate (PMMA) segment, the materials of both the first guiding layer 106 and the second guiding layer 108 may include a random copolymer of styrene (PS) and methyl methacrylate (PMMA).
[0046] In some embodiments, reference Figures 6-7 The coated block copolymer layer 107 can be phase-separated using an annealing process to form alternating and repetitively arranged first block domains 109 and second block domains 110. Exemplarily, after the block copolymer layer 107 and the second guide layer 108 formed by the block copolymer are sequentially formed on the first guide layer 106 and the patterned antireflective layer 103, the process further includes performing a second annealing process to allow the block copolymer to self-assemble. The temperature range of the second annealing process can be 180-270°C, and the annealing time range can be 10-120 min, to ensure that the first block domains 109 and the second block domains 110 can be rearranged and completely phase-separated.
[0047] refer to Figures 6-7The first guiding layer 106, the block copolymer layer 107, and the second guiding layer 108 together constitute a "sandwich" structure. Since the first guiding layer 106 and the second guiding layer 108 can simultaneously control the directional arrangement of polymer blocks in the block copolymer layer 107, that is, the first guiding layer 106 and the second guiding layer 108 have a strong guiding force on the block copolymer layer 107, which can effectively ensure that the first block and the second block in the block copolymer layer 107 are completely separated. Therefore, in some embodiments, along the direction perpendicular to the substrate 101, the thickness of the block copolymer layer 107 can be greater than the thickness of the first guiding layer 106, and the thickness of the first guiding layer 106 can be greater than or equal to the thickness of the second guiding layer 108. That is, when the thickness of the block copolymer layer 107 is greater than the thickness of the first guiding layer 106, the separation of the first block and the second block in the block copolymer layer 107 can also be ensured due to the combined effect of the first guiding layer 106 and the second guiding layer 108. For example, the thickness of the block copolymer layer 107 can range from 30 to 80 nm, the thickness of the first guiding layer 106 can range from 5 to 15 nm, and the thickness of the second guiding layer 108 can range from 5 to 15 nm. The greater the thickness of the block copolymer layer 107, the deeper the etching depth can be achieved. Therefore, in subsequent processes, when etching to form the substrate 101 to form the pattern of the corresponding device, a deeper etching height can be achieved.
[0048] During the self-assembly of the block copolymer layer 107, the polarity of the patterned antireflective layer 103 is enhanced because the sidewalls and top surface of the patterned antireflective layer 103 contain polar materials with fluorine groups after surface modification. Each pattern in the patterned antireflective layer 103 is spaced apart on the mask layer 102, and the width W1 of each pattern is smaller than the width W2 of the first guiding layer 106, that is, the width W1 of each pattern is smaller than the spacing between adjacent patterns. When the block copolymer layer 107 is phase-separated, the antireflective layer 103 can guide any one of two or more different polymer blocks in the block copolymer layer 107 to form on the antireflective layer 103. When the block copolymer layer 107 is phase-separated, two or more different polymer blocks in the block copolymer layer 107 can be alternately and repeatedly arranged on the first guiding layer 106 between the antireflective layers 103.
[0049] Specifically, when the block copolymer includes polystyrene (PS) and polymethyl methacrylate (PMMA) block copolymer materials, i.e., the first block is a styrene polymer (PS) segment and the second block is a polymethyl methacrylate (PMMA) segment, the polarity of the first block is less than that of the second block. Therefore, during the self-assembly of the block copolymer layer 107, in addition to being guided by the first guiding layer 106 and the second guiding layer 108, the more polar second block is further guided by the anti-reflective layer 103. At the same time, they are oriented in the direction toward the anti-reflective layer 103, so that the phase separation of the first block and the second block is more complete, thereby forming the first block domain 109 and the second block domain 110 respectively. The first block domain 109 and the second block domain 110 are alternately and repeatedly arranged on the first guiding layer 106. Meanwhile, some of the second block domains 110 are also distributed on the patterned anti-reflective layer 103.
[0050] In some embodiments, the first segment field 109 and the second segment field 110 may be formed to have substantially the same width, and the width W2 of the first guide layer 106 may be an integer multiple of the width of the first segment field 109 or the second segment field 110.
[0051] S600 etching removes the second guide layer 108 and the second segment region 110, retaining the first segment region 109 to form the target pattern. In some embodiments, reference is made to... Figure 8 The second guiding layer 108 and the second block region 110 are etched away, leaving the first block region 109 to form the target pattern. The etching process may include, but is not limited to, reactive ion etching, and the etching gas may include, but is not limited to, oxygen (O2), argon (Ar), or fluorine-containing hydrocarbons (C). x H y F z For example, when the etching gas is a fluorinated hydrocarbon (C... x H y F z When etching, it can protect the first segment domain 109 while increasing the etching rate of the second segment domain 110. For example, the etching selectivity ratio of the second segment to the first segment can be in the range of 2:1 to 5:1, and the etching selectivity ratio of the second segment to the first guide layer 106 or the second guide layer 108 can be in the range of 1:1 to 3:1. Specifically, the etching selectivity ratio of the second segment, the first guide layer 106 and the first segment can be 3:1.5:1. Therefore, when etching away the second segment domain, the integrity of the first segment domain 109 can be effectively guaranteed.
[0052] The technical solution provided in this disclosure involves sequentially forming a block copolymer layer and a second guiding layer on a first guiding layer, followed by self-assembly of the block copolymer layer to form a first block domain and a second block domain formed by the first and second blocks of the block copolymer, respectively. The first and second block domains are alternately and repeatedly arranged on the first guiding layer. By forming a block copolymer layer between the first and second guiding layers and allowing it to self-assemble, the orderliness of the arrangement of the first and second blocks can be effectively improved, ensuring the quality of pattern formation, and making it possible to further increase the etching depth of the substrate pattern.
[0053] In some embodiments, reference Figures 9-10 After etching away the second guiding layer 108 and the second segment region 110, retaining the first segment region 109 to form the target pattern, the process further includes: patterning a mask layer 102 using the target pattern as a mask; and patterning the substrate 101 using the patterned mask layer 102 as a mask. Specifically, after etching away the second guiding layer 108 and the second segment region 110, retaining the first segment region 109 to form the target pattern, the mask layer 102 is patterned using the target pattern as a mask, and the first segment region 109 and the anti-reflection layer 103 are removed. Then, the substrate 101 is etched using the patterned mask layer 102 as a mask. The patterning process includes, but is not limited to, dry etching to reduce damage to the pattern and avoid structural defects.
[0054] In some embodiments, the pattern of substrate 101 may include, but is not limited to, linear, circular, or star-shaped patterns. The pattern of substrate 101 may be used to form active pillars or active regions of transistors, metal wiring layers, or contact holes.
[0055] Various embodiments of the patterning method disclosed herein can be applied to the fabrication of device structures in highly integrated semiconductor chips, which may be memory semiconductor chips including memory devices. Exemplarily, the memory devices include volatile memory devices, such as dynamic random access memory (DRAM) or static random access memory (SRAM). The memory semiconductor chip includes semiconductor devices, which include multiple individual devices of various types. These individual devices include various microelectronic devices, such as metal-oxide-semiconductor field-effect transistors (MOSFETs) containing CMOS transistors, system-on-a-scale integrated circuits (LSIs), active devices, or passive devices. In some embodiments, taking DRAM as an example, the memory structure may include peripheral circuitry and a memory region, the peripheral circuitry region including transistors, passive devices, or active devices, wherein the transistors include doped source / drain regions and gate structures.
[0056] In some embodiments, various types of integrated circuits and microelectronic devices can be manufactured using the embodiments of this disclosure. Exemplarily, integrated circuits may include, but are not limited to, processors, chipset components, graphics processors, digital signal processors, microcontrollers, etc. In other embodiments, the integrated circuits or other microelectronic devices can also be used in a wide variety of electronic devices known in the art, such as computer systems (e.g., desktops, laptops, servers), mobile phones, personal electronic devices, etc., and can be connected to buses and other components in the system; for example, a processor can be connected to memory, chipsets, etc., via one or more buses.
[0057] This disclosure also includes a computing device that may include components fabricated by the patterning method described in the embodiments of this disclosure. These components may or may not be physically and electrically connected to the substrate. These components may include, but are not limited to: volatile memory (e.g., DRAM), non-volatile memory (e.g., ROM), flash memory, graphics processor, digital signal processor, cryptographic processor, chipset, antenna, display, touchscreen display, touchscreen controller, battery, audio codec, video codec, power amplifier, global positioning system (GPS) device, compass, accelerometer, gyroscope, speaker, camera, and mass storage device (e.g., hard disk drive, optical disc (CD), digital multifunction disc (DVD), etc.).
[0058] Those skilled in the art will understand that the above embodiments are specific examples of implementing this disclosure, and in practical applications, various changes in form and detail may be made without departing from the spirit and scope of the embodiments of this disclosure. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of the embodiments of this disclosure; therefore, the scope of protection of the embodiments of this disclosure should be determined by the scope defined in the claims.
Claims
1. A method for forming a pattern, characterized in that, include: Provide substrate; A mask layer and an anti-reflection layer are sequentially formed on the substrate; The antireflective layer is patterned to form a first trench, the first trench exposing a portion of the mask layer; A first guiding layer is formed in the first trench, and the first guiding layer fills the first trench; A block copolymer layer and a second guiding layer formed of block copolymers are sequentially formed on the first guiding layer and the patterned antireflective layer, and the block copolymers are self-assembled to form a first block domain and a second block domain formed of the first block and the second block of the block copolymers, respectively, wherein the first block domain and the second block domain are alternately and repeatedly arranged on the first guiding layer. The second guide layer and the second segment domain are etched away, while the first segment domain is retained to form the target pattern.
2. The method according to claim 1, characterized in that, The materials of both the first guiding layer and the second guiding layer include a random copolymer of styrene and methyl methacrylate.
3. The method according to claim 1, characterized in that, Along a direction perpendicular to the substrate, the thickness of the first guiding layer is greater than or equal to the thickness of the second guiding layer.
4. The method according to claim 4, characterized in that, Along a direction perpendicular to the substrate, the thickness of the block copolymer layer is greater than the thickness of the first guiding layer.
5. The method according to claim 1, characterized in that, Before the first guiding layer is formed within the first trench. Also includes: The patterned antireflective layer is then surface modified.
6. The method according to claim 5, characterized in that, The surface-modifying gas includes fluorine-containing hydrocarbons.
7. The method according to claim 1, characterized in that, After forming the first guiding layer within the first trench, the method further includes: The first guiding layer is subjected to a first annealing process, wherein the temperature range of the first annealing process is 180-250℃ and the annealing time range is 5-20min.
8. The method according to claim 1, characterized in that, After the block copolymer layer and the second guiding layer formed by the block copolymer are sequentially formed on the first guiding layer and the patterned antireflective layer, the method further includes: performing a second annealing process to enable the block copolymer to self-assemble, wherein the temperature range of the second annealing process is 180-270°C and the annealing time range is 10-120 min.
9. The method according to claim 1, characterized in that, The etching selectivity ratio between the second segment and the first segment ranges from 2:1 to 5:1, and the etching selectivity ratio between the second segment and the first or second guiding layer ranges from 1:1 to 3:
1.
10. The method according to claim 1, characterized in that, After etching away the second guiding layer and the second segment region while retaining the first segment region to form the target pattern, the method further includes: using the target pattern as a mask to pattern the mask layer; and using the patterned mask layer as a mask to pattern the substrate.