Aromatic underlayer

Abstract

To provide aromatic underlayers which cure at relatively low temperatures, have good solubility in common processing solvents, and do not suffer from metal catalyst, boron, halogen, and / or phosphorus contamination.SOLUTION: The present invention provides a coating composition comprising a polymer and an organic solvent, wherein the polymer comprises a repeating unit represented by formula (1').SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates generally to the field of manufacturing electronic devices, and more particularly to the field of materials for use as underlayers in semiconductor manufacturing. [Background technology]

[0002] It is known in lithography processes that resist patterns can collapse when they are very high (high aspect ratio) due to surface tension from the developer used. Multilayer resist processes (e.g., three- and four-layer processes) have been devised to address this problem of pattern collapse when high aspect ratios are desired. These multilayer processes use a top resist layer, one or more center layers, and a bottom (or underlayer) layer. In these multilayer resist processes, the top photoresist layer is typically imaged and developed to provide a resist pattern. The pattern is then transferred to one or more center layers, typically by etching. Each center layer is selected to use a different etch method, such as a different plasma etch. Finally, the pattern is transferred to the underlayer, typically by etching. While these center layers can be composed of a variety of materials, the underlayer material is typically composed of a high-carbon content material. The underlayer material is selected to provide desired anti-reflective properties, planarization properties, and etch selectivity.

[0003] Current technologies for underlayers include chemical vapor deposition (CVD) carbon and solution-processed high-carbon-content polymers. CVD materials have several significant limitations, such as high cost of ownership, the inability to form a planarizing layer over the surface morphology on the substrate, and high absorbance at 633 nm, which is used for pattern alignment. For these reasons, the industry has proposed solution-processed high-carbon-content materials as underlayers. An ideal underlayer should meet the following properties: it should be able to be cast onto the substrate by spin-coating methods; it should be thermally curable (hardened) with low outgassing and sublimation when heated; it should be soluble in common processing solvents for good equipment compatibility; it should have suitable n and k values ​​to work with currently used silicon hard masks and backside antireflective coating (BARC) layers to provide the low reflectivity required for photoresist imaging; and it should be thermally stable up to >400 °C to avoid damage during subsequent CVD processes, such as silicon oxynitride (SiON), silicon nitride, silicon oxide, etc. [Prior art documents] [Non-patent literature]

[0004] [Non-Patent Document 1] S.Amou et al. “Synthesis of Regiocontrolled Polymer Having 2-Naphthol Unit by CuCl-amine Catalyzed Oxidative Coupling Polymerization,” Journal of Polymer Science:Part A:polymer Chemistry,Vol.37,pp 3702-3709,1999 Summary of the Invention [Problem to be solved by the invention]

[0005] Aromatic building blocks are typically used to provide underlayer materials with desirable thermal stability. However, underlayer materials with high aromatic carbon content tend to suffer from poor solubility in common processing solvents. Various attempts have been made to prepare underlayer materials with high aromatic content using conventional novolak polymerization methods to introduce hydroxyl groups and aliphatic carbons into the polymer. There remains a need for underlayer materials that cure at relatively low temperatures, have good solubility in common processing solvents, and are free from the drawbacks of metal catalysts, boron, halogen, and / or phosphorus contamination. [Means for solving the problem]

[0006] The present invention provides a method for preparing a coating composition comprising the steps of: (a) providing an electronic device substrate; and (b) coating a layer of a coating composition comprising one or more curable compounds on a surface of the electronic device substrate, the one or more curable compounds being represented by Formula (1).

[0007] [ka]

[0008] (wherein Z is a covalent chemical bond or O, C(=O), S, S(=O), S(=O), N(R), C 1-100 -hydrocarbylene, substituted C 1-100 -hydrocarbylene, -O-(C 1-20 -alkylene-O-) m1 , -O-(C 5-60 -arylene-O-) m2 and C(R 3 )(R 4 ) is a divalent linking group selected from; 1-20 -Alkyl, C 5-30 -aryl and C 2-20 - selected from unsaturated aliphatic moieties; each R 1 and each R 2 are independently H, OR, C 1-30 -hydrocarbyl, substituted C 1-30 -hydrocarbyl, -C(=O)-OR 5, SR, S(=O)R, S(=O)2R, N(R 5 )(R 6 ) and N(R 7 )C(=O)R 5 Selected from; 1 R 1 and one R 2 and Z together with the atoms to which they are attached can form a 5- or 6-membered ring; R 3 and R 4 are independently, C 1-20 -Alkyl and C 5-30 -aryl; R 3 and R 4 may, together with the carbons to which they are attached, form a 5- or 6-membered ring which may be fused to one or more aromatic rings and which may be optionally substituted; R 5 and R 6 are independently, C 1-20 -Alkyl or C 5-30 -aryl; R 7 is H or R 6 and;R 5 and R 6 can form a 5- or 6-membered ring together with the atom to which they are attached; each of a1 and a2 is 0 to 5; each of m1 and m2 is 1 to 100; and n is 2 to 1000). (c) curing the layer of curable compound to form an underlayer; (d) coating a layer of photoresist on the underlayer; (e) exposing the photoresist layer to actinic radiation through a mask; (f) developing the exposed photoresist layer to form a resist pattern; and (g) transferring the pattern to the underlayer to expose a portion of the electronic device substrate.

[0009] Also, an electronic device including an electronic device substrate having a layer of a polymer containing one or more curable compounds as polymerized units on a surface of the electronic device substrate, wherein the one or more curable compounds are represented by the formula (1)

[0010] [ka]

[0011] (wherein Z is a covalent chemical bond or O, C(=O), S, S(=O), S(=O), N(R), C 1-100 -hydrocarbylene, substituted C 1-100 -hydrocarbylene, -O-(C 1-20 -alkylene-O-) m1 , -O-(C 5-60 -arylene-O-) m2 and C(R 3 )(R 4 ) is a divalent linking group selected from; 1-20 -Alkyl, C 5-30 -aryl and C 2-20 - selected from unsaturated aliphatic moieties; each R 1 and each R 2 are independently H, OR, C 1-30 -hydrocarbyl, substituted C 1-30 -hydrocarbyl, -C(=O)-OR 5 , SR, S(=O)R, S(=O)2R, N(R 5 )(R 6 ) and N(R 7 )C(=O)R 5 Selected from; 1 R 1 and one R 2 and Z together with the atoms to which they are attached can form a 5- or 6-membered ring; R 3 and R 4 are independently, C 1-20 -Alkyl and C 5-30 -aryl; R 3 and R 4 may, together with the carbons to which they are attached, form a 5- or 6-membered ring which may be fused to one or more aromatic rings and which may be optionally substituted; R 5 and R 6 are independently, C 1-20 -Alkyl or C 5-30 -aryl; R 7 is H or R 6 and;R 5 and R 6can form a 5- or 6-membered ring together with the atom to which they are attached; each of a1 and a2 is 0 to 5; each of m1 and m2 is 1 to 100; and n is 2 to 1000). The present invention provides an electronic device, wherein the polymer comprises a repeat unit of

[0012] The present invention relates to a compound represented by formula (1)

[0013] [ka]

[0014] (wherein Z is a covalent chemical bond or O, C(=O), S, S(=O), S(=O), N(R), C 1-100 -hydrocarbylene, substituted C 1-100 -hydrocarbylene, -O-(C 1-20 -alkylene-O-) m1 , -O-(C 5-60 -arylene-O-) m2 and C(R 3 )(R 4 ) is a divalent linking group selected from; 1-20 -Alkyl, C 5-30 -aryl and C 2-20 - selected from unsaturated aliphatic moieties; each R 1 and each R 2 are independently H, OR, C 1-30 -hydrocarbyl, substituted C 1-30 -hydrocarbyl, -C(=O)-OR 5 , SR, S(=O)R, S(=O)2R, N(R 5 )(R 6 ) and N(R 7 )C(=O)R 5 Selected from; 1 R 1 and one R 2 and Z together with the atoms to which they are attached can form a 5- or 6-membered ring; R 3 and R 4 are independently, C 1-20 -Alkyl and C 5-30 -aryl; R 3and R 4 may, together with the carbons to which they are attached, form a 5- or 6-membered ring which may be fused to one or more aromatic rings and which may be optionally substituted; R 5 and R 6 are independently, C 1-20 -Alkyl or C 5-30 -aryl; R 7 is H or R 6 and;R 5 and R 6 can form a 5- or 6-membered ring together with the atom to which they are attached; each of a1 and a2 is 0 to 5; each of m1 and m2 is 1 to 100; and n is 2 to 1000). Further provided is a polymer comprising repeat units of

[0015] Also provided by the present invention is a method for filling gaps (or apertures), comprising the steps of: (a) providing a semiconductor substrate having a relief image on a surface of the substrate that includes a plurality of gaps to be filled; (b) applying a coating layer of one or more of the polymers described above over the relief image; and (c) heating the coating layer at a temperature sufficient to cure the coating layer. DETAILED DESCRIPTION OF THE INVENTION

[0016] When an element is referred to as being "on" another element, it will be understood that it may be directly adjacent to the other element or that intervening elements may be present between them. In contrast, when an element is referred to as being "directly on" another element, there are no intervening elements present. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0017] Terms such as first, second, and third may be used herein to describe various elements, components, regions, layers, and / or sections, but it will be understood that these elements, components, regions, layers, and / or sections should not be limited by these terms. These terms are used merely to distinguish one element, component, region, layer, or section from another element, component, region, layer, or section. Thus, a first element, component, region, layer, or section discussed below could be referred to as a second element, component, region, layer, or section without departing from the teachings of the present invention.

[0018] As used throughout this specification, the following abbreviations shall have the following meanings unless the context clearly dictates otherwise: °C = degrees Celsius; g = grams; mg = milligrams; L = liters; mL = milliliters; Å = angstroms; nm = nanometers; μm = microns = micrometers; mm = millimeters; sec. = seconds; min. = minutes; hr. = hours; DI = deionized; and Da = Daltons. The abbreviation "wt. %" means percent by weight based on the total weight of the referenced composition, unless otherwise specified. All amounts are % by weight and all ratios are molar ratios unless otherwise specified. All numerical ranges are inclusive and combinable in any order, except where clearly conditioned that such numerical ranges add up to 100%. The articles "a," "an," and "the" refer to the singular and the plural.

[0019] "Alkyl" means straight-chain, branched, and cyclic alkyl unless otherwise specified. "Alkenyl" means straight-chain, branched, and cyclic alkenyl unless otherwise specified. "Halogen" means fluorine, chlorine, bromine, and iodine. "Alkyl" includes "heteroalkyl" unless otherwise specified. The term "heteroalkyl" means an alkyl group having one or more heteroatoms, such as nitrogen, oxygen, sulfur, or phosphorus, replacing one or more carbon atoms in the group, as in, for example, an ether or thioether. In a preferred embodiment, "alkyl" does not include "heteroalkyl." When the number of carbons is not specified for any alkyl or heteroalkyl, 1 to 20 carbons are contemplated. When the number of carbons is not specified for any alkenyl or alkynyl, 2 to 20 carbons are contemplated. "Aryl" includes aromatic carbocycles and aromatic heterocycles. Preferably, the aryl moiety is an aromatic carbocycle. "Substituted aryl" refers to an aryl group in which one or more of its hydrogens is replaced with a halogen, C 1-6 -Alkyl, Halo-C 1-6 -Alkyl, C 1-6 -Alkoxy, Halo-C 1-6 -alkoxy, phenyl and phenoxy, preferably halogen, C 1-6 -Alkyl, Halo-C 1-4 -Alkyl, C 1-6 -Alkoxy, Halo-C 1-4 -alkoxy and phenyl, more preferably halogen, C 1-6 -Alkyl, C 1-6- refers to any aryl moiety substituted with one or more substituents selected from alkoxy, phenyl, and phenoxy. Preferably, substituted aryl has 1 to 3 substituents, more preferably 1 or 2. The terms "hydrocarbyl" and "hydrocarbylene" refer to saturated and unsaturated aliphatic and alicyclic moieties and aromatic hydrocarbon moieties, each of which may contain one or more heteroatoms selected from O, S, and N. Preferred "hydrocarbyl" moieties are alkyl, alkenyl, alkynyl, and aryl moieties. Similarly, preferred "hydrocarbylene" moieties are alkylene, alkenylene, alkynylene, and arylene. The term "optionally substituted hydrocarbyl" or "optionally substituted hydrocarbylene" refers to substituted and unsubstituted alkyl or alkylene, substituted and unsubstituted alkene or alkenylene, substituted and unsubstituted alkynyl or alkynylene, and substituted and unsubstituted aryl or arylene. The terms "substituted hydrocarbyl" and "substituted hydrocarbylene" refer to a hydrocarbyl or hydrocarbylene moiety in which one or more of its hydrogens has been replaced by one or more inert substituents. The term "inert substituent" refers to any substituent that does not react during the polymerization process used to form the present polymer. Typical inert substituents are C 1-20 -alkoxy, C 5-20 -aryl, C 1-20 -Alkyl, C 2-20 -Alkenyl, C 2-20 -alkynyl, hydroxyl and halogen.

[0020] As used herein, the term "polymer" includes oligomers. The term "oligomer" refers to dimers, trimers, tetramers, and other polymeric materials that can be further cured. The term "curing" refers to any process, such as polymerization or condensation, that increases the overall molecular weight of the polymer, or removes solubility-promoting groups from the polymer, or alternatively increases the overall molecular weight and removes solubility-promoting groups. "Curable" refers to any material that can be cured under certain conditions. As used herein, "gap" refers to any aperture on a semiconductor substrate that is intended to be filled with a gap-fill composition.

[0021] In the manufacture of electronic devices, an aromatic underlayer can be prepared by the steps of: (a) providing an electronic device substrate; and (b) coating a layer of a coating composition on a surface of the electronic device substrate, the coating composition comprising one or more curable compounds, the one or more curable compounds having a formula (1):

[0022] [ka]

[0023] (wherein Z is a covalent chemical bond or O, C(=O), S, S(=O), S(=O), N(R), C 1-100 -hydrocarbylene, substituted C 1-100 -hydrocarbylene, -O-(C 1-20 -alkylene-O-) m1 , -O-(C 5-60 -arylene-O-) m2 and C(R 3 )(R 4 ) is a divalent linking group selected from; 1-20 -Alkyl, C 5-30 -aryl and C 2-20 - selected from unsaturated aliphatic moieties; each R 1 and each R 2 are independently H, OR, C 1-30 -hydrocarbyl, substituted C 1-30 -hydrocarbyl, -C(=O)-OR 5, SR, S(=O)R, S(=O)2R, N(R 5 )(R 6 ) and N(R 7 )C(=O)R 5 Selected from; 1 R 1 and one R 2 and Z together with the atoms to which they are attached can form a 5- or 6-membered ring; R 3 and R 4 are independently, C 1-20 -Alkyl and C 5-30 -aryl; R 3 and R 4 may, together with the carbons to which they are attached, form a 5- or 6-membered ring which may be fused to one or more aromatic rings and which may be optionally substituted; R 5 and R 6 are independently, C 1-20 -Alkyl or C 5-30 -aryl; R 7 is H or R 6 and;R 5 and R 6 can form a 5- or 6-membered ring together with the atom to which they are attached; each of a1 and a2 is 0 to 5; each of m1 and m2 is 1 to 100; and n is 2 to 1000). (c) curing a layer of a curable compound to form an underlayer; (d) coating a layer of photoresist on the underlayer; (e) exposing the photoresist layer to actinic radiation through a mask; (f) developing the exposed photoresist layer to form a resist pattern; and (g) transferring the pattern to the underlayer to expose a portion of the electronic device substrate. The substrate is then patterned, and the patterned underlayer is removed. In a preferred embodiment, a layer of photoresist is coated directly on the underlayer. In another preferred embodiment, one or more layers of a silicon-containing composition, an organic antireflective composition (BARC), and combinations thereof are coated directly on the underlayer and optionally cured before step (d) to form a central layer, and then a layer of photoresist is coated directly on one or more of the silicon-containing composition layer, the BARC layer, or each layer. When a silicon-containing central layer is used, the pattern is transferred to the silicon-containing central layer after step (f) and before step (g).

[0024] Various electronic device substrates can be used in the present invention, such as multichip modules, flat panel display substrates, integrated circuit substrates, substrates for light-emitting diodes (LEDs), such as organic light-emitting diodes (OLEDs), semiconductor wafers, and packaging substrates, including polycrystalline silicon substrates, with semiconductor wafers being preferred. Such substrates are typically composed of one or more of silicon, polysilicon, silicon oxide, silicon nitride, silicon oxynitride, silicon germanium, gallium arsenide, aluminum, sapphire, tungsten, titanium, titanium-tungsten, nickel, copper, and gold. Suitable substrates may be in the form of wafers, such as those used in the manufacture of integrated circuits, optical sensors, flat panel displays, integrated optical circuits, and LEDs. As used herein, the term "semiconductor wafer" is intended to include "semiconductor substrates," "semiconductor devices," and various packages for various levels of interconnection, such as single-chip wafers, multiple-chip wafers, packages for various levels, or other assemblies requiring solder connections. Such substrates may be of any suitable size. The preferred wafer substrate diameter is 200 mm to 300 mm, although wafers having smaller and larger diameters may be suitably used with the present invention. As used herein, the term "semiconductor substrate" includes any substrate having one or more semiconductor layers or structures that may optionally contain active or operable portions of a semiconductor device. A semiconductor device refers to a semiconductor substrate upon which at least one microelectronic device has been or is being batch fabricated.

[0025] Optionally, a layer of adhesion promoter can be applied to the substrate surface before depositing the coating composition, which is then cured to form the underlayer. If an adhesion promoter is desired, any suitable adhesion promoter for polymer films can be used, such as a silane, preferably an organosilane such as trimethoxyvinylsilane, triethoxyvinylsilane, or hexamethyldisilazane, or an aminosilane coupling agent such as gamma-aminopropyltriethoxysilane. Particularly suitable adhesion promoters include those sold under the trade names AP3000, AP8000, and AP9000S, available from Dow Electronic Materials (Marlborough, Massachusetts).

[0026] The coating compositions useful in the present invention comprise one or more curable compounds, the curable compounds being of formula (1)

[0027] [ka]

[0028] (wherein Z is a covalent chemical bond or O, C(=O), S, S(=O), S(=O), N(R), C 1-100 -hydrocarbylene, substituted C 1-100 -hydrocarbylene, -O-(C 1-20 -alkylene-O-) m1 , -O-(C 5-60 -arylene-O-) m2 and C(R 3 )(R 4 ) is a divalent linking group selected from; 1-20 -Alkyl, C 5-30 -aryl and C 2-20 - selected from unsaturated aliphatic moieties; each R 1 and each R 2 are independently H, OR, C 1-30 -hydrocarbyl, substituted C 1-30 -hydrocarbyl, -C(=O)-OR 5 , SR, S(=O)R, S(=O)2R, N(R 5 )(R6 ) and N(R 7 )C(=O)R 5 Selected from; 1 R 1 and one R 2 and Z together with the atoms to which they are attached can form a 5- or 6-membered ring; R 3 and R 4 are independently, C 1-20 -Alkyl and C 5-30 -aryl; R 3 and R 4 may, together with the carbons to which they are attached, form a 5- or 6-membered ring which may be fused to one or more aromatic rings and which may be optionally substituted; R 5 and R 6 are independently, C 1-20 -Alkyl or C 5-30 -aryl; R 7 is H or R 6 and;R 5 and R 6 can form a 5- or 6-membered ring together with the atom to which they are attached; each of a1 and a2 is 0 to 5; each of m1 and m2 is 1 to 100; and n is 2 to 1000). A polymer containing the repeating unit of the formula: 1-100 -hydrocarbylene moiety is C 1-50 -Alkylene, C 2-50 -Alkenylene, C 2-50 -alkynylene and C 5-30 -arylene, more preferably C 1-20 -Alkylene, C 2-20 -Alkenylene, C 2-20 -alkynylene and C 5-30 -arylene. Z is a covalent chemical bond or O, C(=O), S, S(=O), S(=O)2, N(R), C 1-50 -hydrocarbylene, -O-(C 1-20 -alkylene-O-) m1 , -O-(C 5-60 -arylene-O-) m2 and C(R 3 )(R 4), more preferably a covalent chemical bond or O, C(=O), S, S(=O), C 1-50 -hydrocarbylene, -O-(C 5-60 -arylene-O-) m2 and C(R 3 )(R 4 ), and even more preferably a covalent chemical bond, O, C(=O), S, S(=O), C 5-60 -arylene, -O-(C 5-60 -arylene-O-) m2 and C(R 3 )(R 4 ), and even more preferably a covalent chemical bond, O, C(=O), S, C 5-60 -arylene, -O-(C 5-60 -arylene-O-) m2 and C(R 3 )(R 4 R is preferably selected from H, C 1-20 -Alkyl and C 5-30 -aryl. Preferably, R 1 and R 2 each independently selected from H, OR and C 1-30 -hydrocarbyl, more preferably independently H or C 1-30 -hydrocarbyl, even more preferably C 10-15 -hydrocarbyl. Even more preferably, one R 1 and one R 2 and Z together with the atoms to which they are attached form a 5- or 6-membered ring. 1 and R 2 Preferred C 1-30 - the hydrocarbyl moiety is C 1-30 -Alkyl, C 2-30 -Alkenyl, C 2-30 -alkynyl and C 5-30 -aryl, more preferably C 1-20 -Alkyl, C 1-20 -Alkenyl, C 2-20 -alkynyl and C 5-30-aryl. Each of a1 and a2 is preferably 0 to 2, more preferably 0 or 1. In a preferred embodiment, a1=a2, and even more preferably a1=a2=0 or 1. Those skilled in the art will understand that each of the subscripts n, m1, and m2 refers to the number of repeating units. Preferably, each of m1 and m2 is 1 to 50, more preferably 1 to 25, and even more preferably 1 to 10. It is preferred that n=2 to 500, more preferably 2 to 100, even more preferably 2 to 50, and even more preferably 2 to 20.

[0029] Preferred compounds of formula (1) are those in which a1 and a2 are each 0 or 1, and Z=a single covalent bond, O, phenylene, pyrenylene, anthracenylene, phenanthracenylene, —O-phenylene-O—, —O-naphthylene-O—, —C(R 3 )(R 4 ) and -O-phenylene-C(R 3 )(R 4 )-phenylene-O-. 3 )(R 4 )-, one preferred divalent linking group is of the formula

[0030] [ka]

[0031] (wherein * denotes the point of attachment to the moiety of formula (1)) When Z=O, one R 1 and one R 2 and R form a 6-membered fused heterocyclic ring together, and more preferably, one R 1 and one R 2 and are both expressed as follows:

[0032] [ka]

[0033] (wherein * denotes the point of attachment to the moiety of formula (1)) It is even more preferred that the hydroxyl group forms part of the hydroxyl group.

[0034] The curable compounds of the present invention are typically prepared by oxidative coupling polymerization of a monomer having a 2-naphthol moiety using a copper chloride-amine complex as a catalyst. A preferred catalyst is di-μ-hydroxo-bis-[(N,N,N',N'-tetramethylethylenediamine)copper(II)] chloride. Such oxidative coupling polymerizations are typically carried out in air at room temperature. Suitable oxidative coupling polymerizations are disclosed in (Non-Patent Document 1). A preferred monomer having a 2-naphthol moiety useful for preparing the present curable polymer is represented by the formula (2):

[0035] [ka]

[0036] (In the formula, R 1 , R 2 , Z, a1 and a2 are as described above for formula (1), and the 1 position is unsubstituted. The monomer of formula (2) is polymerized to form a curable polymer having repeating units of formula (1). The monomer of formula (2) must be unsubstituted at the 1-position. The monomer of formula (2) is attached (i.e., polymerized) at the 1-position of the 2-naphthol moiety as shown in the repeating unit of formula (1). The curable polymer is a homopolymer, with each end of the polymer terminated with an unreacted 2-naphthol moiety. A preferred monomer of formula (2) is formula (2-1):

[0037] [ka]

[0038] (In the formula, R 1 , R 2 , Z, a1 and a2 are as described above for formula (1), and the 1 position is unsubstituted. Preferred monomers of formula (2-1) are monomers of formulae (2a) to (2f).

[0039] [ka]

[0040] Monomers (2a) to (2f) are used to prepare polymers having repeating units (1a) to (1f), respectively (n in each case means the degree of polymerization or the number of repeating units (n=2 to 1000)).

[0041] [ka]

[0042] In addition to one or more curable compounds described above, the coating composition may optionally and preferably includes one or more organic solvents. Suitable organic solvents are any organic solvents that dissolve one or more curable compounds, preferably organic solvents commonly used in the manufacture of electronic devices. A single organic solvent may be used, or a mixture of organic solvents may be used. Suitable organic solvents include, but are not limited to, ketones such as cyclohexanone and 2-heptanone; alcohols such as 3-methoxybutanol, 3-methyl-3-methoxybutanol, 1-methoxy-2-propanol, and 1-ethoxy-2-propanol; ethers such as propylene glycol methyl ether (PGME), propylene glycol ethyl ether (PGEE), ethylene glycol monomethyl ether, propylene glycol monoethyl ether, ethylene glycol monoethyl ether, propylene glycol dimethyl ether, and diethylene glycol dimethyl ether. ethers, anisole; esters such as propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monoethyl ether acetate, ethyl lactate (EL), methyl hydroxyisobutyrate (HBM), ethyl pyruvate, butyl acetate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, tert-butyl acetate, tert-butyl propionate, and propylene glycol mono-tert-butyl ether acetate; lactones such as gamma-butyrolactone, and any combination of the foregoing. Preferred solvents are PGME, PGEE, PGMEA, EL, HBM, and combinations thereof.

[0043] The coating composition may also include one or more coating additives typically used in such coatings, such as, for example, a curing agent, a crosslinking agent, a surface leveling agent, etc. The selection of such optional additives and their amounts is well within the ability of one skilled in the art. The curing agent is typically present in an amount of 0 to 20 wt. % based on total solids, preferably 0 to 3 wt. %. The crosslinking agent is typically used in an amount of 0 to 30 wt. % based on total solids, preferably 3 to 10 wt. %. The surface leveling agent is typically used in an amount of 0 to 5 wt. % based on total solids, preferably 0 to 1 wt. %. The selection of such optional additives to be used and their amounts is well within the ability of one skilled in the art.

[0044] A curing agent may optionally be used in the coating composition to promote the curing of the deposited curable compound. A curing agent is any component that causes the curing of the curable compound on the surface of the substrate. Preferred curing agents are acids and thermal acid generators. Suitable acids include, but are not limited to, arylsulfonic acids, such as p-toluenesulfonic acid; alkylsulfonic acids, such as methanesulfonic acid, ethanesulfonic acid, and propanesulfonic acid; and perfluoroalkylsulfonic acids, such as trifluoromethanesulfonic acid and perfluoroarylsulfonic acid. A thermal acid generator is any compound that liberates an acid upon exposure to heat. Thermal acid generators are known in the art and are generally commercially available, for example, from King Industries (Norwalk, Connecticut). Typical thermal acid generators include, but are not limited to, amine-blocked strong acids, such as amine-blocked sulfonic acids, such as amine-blocked dodecylbenzenesulfonic acid. Those skilled in the art will also understand that certain photoacid generators can liberate acid upon heating and function as thermal acid generators.

[0045] Any suitable crosslinker may be used in the present composition, provided that such crosslinker has at least two, and preferably at least three, moieties that can react with the present aromatic resin reaction product under suitable conditions, such as, for example, acidic conditions. Typical crosslinkers include, but are not limited to, novolac resins, epoxy-containing compounds, melamine compounds, guanamine compounds, isocyanate-containing compounds, benzocyclobutene, and the like, preferably methylol, C1-C 10 Alkoxymethyl and C2-C 10 Included are any of the aforementioned crosslinkers having two or more, preferably three or more, and more preferably four substituents selected from acyloxymethyl. Examples of suitable crosslinkers are those represented by formulas (3) and (4).

[0046] [ka]

[0047] Such cross-linking agents are known in the art and are commercially available from a variety of sources.

[0048] The coating composition can optionally contain one or more surface leveling agents (or surfactants).Any suitable surfactant can be used, but such surfactants are typically nonionic.Typical nonionic surfactants are nonionic surfactants containing alkyleneoxy bonds, such as ethylene epoxy, propylene oxy, or a combination of ethylene epoxy and propylene oxy bonds.

[0049] The coating composition can be coated onto an electronic device substrate by any suitable means, such as spin coating, slot die coating, doctor blading, curtain coating, roller coating, spray coating, dip coating, etc. Spin coating is preferred. In a typical spin coating method, the composition is applied to a substrate rotating at a speed of 500 to 4000 rpm for 15 to 90 seconds to obtain a desired layer of the coating composition on the electronic device substrate. It will be understood by those skilled in the art that the height of the coating composition layer can be adjusted by varying the spin speed.

[0050] After being coated onto the substrate, the coating composition layer is optionally baked at a relatively low temperature to remove any organic solvents and other relatively volatile components from the layer. Typically, the substrate is baked at a temperature of 80 to 150°C, although other suitable temperatures may be used. The baking time is typically 10 seconds to 10 minutes, preferably 30 seconds to 5 minutes, although longer or shorter times may be used. When the substrate is a wafer, such a baking step may be carried out by heating the wafer on a hotplate. After solvent removal, a layer, film, or coating of the curable compound is obtained on the surface of the substrate.

[0051] The curable compound layer is then sufficiently cured to form the aromatic underlayer, preventing the film from intermixing with subsequently applied coating layers, such as photoresist or other layers coated directly on top of the aromatic underlayer. The underlayer can be cured in an oxygen-containing atmosphere, such as air, or in an inert atmosphere, such as nitrogen, preferably in an oxygen-containing atmosphere. The curing conditions used are sufficient to harden the film so that it does not intermix with subsequently applied organic layers, such as photoresist layers, while maintaining the desired antireflective properties (n and k values), etch selectivity, gap filling, and planarization of the underlayer film. This curing step is preferably carried out on a hotplate-type apparatus, although oven curing can be used to achieve consistent results. Typically, such curing is carried out by heating the underlayer to a curing temperature of ≥ 150°C, preferably ≥ 170°C, and more preferably ≥ 200°C. The selected curing temperature can be sufficient to cure the aromatic underlayer. Suitable temperature ranges for curing the aromatic underlayer are 150-400°C, preferably 170-350°C, and more preferably 200-250°C. Such a curing step may take from 10 seconds to 10 minutes, preferably 1 to 3 minutes, more preferably 1 to 2 minutes, although other suitable times may be used.

[0052] An initial bake step may not be necessary if the curing step is performed so that rapid release of solvent and curing of by-products does not impair the quality of the underlying film. For example, a ramp bake, starting at a relatively low temperature and then gradually increasing to a temperature of ≥ 200°C, can produce acceptable results. In some cases, it may be preferable to have a two-stage cure process, with the first stage being a lower bake temperature below 150°C and the second stage being a higher bake temperature of ≥ 200°C. The two-stage cure process promotes uniform filling and planarization of existing substrate surface topography, such as filling trenches and vias.

[0053] After the underlayer is cured, one or more processing layers, such as a photoresist, a silicon-containing layer, a hard mask layer, or a back surface antireflective coating (or BARC) layer, can be coated on the cured underlayer. For example, a photoresist can be coated directly onto the surface of a silicon-containing layer or other central layer directly on top of the resin underlayer, such as by spin coating, or alternatively, the photoresist can be coated directly onto the cured underlayer. Various photoresists, such as those used in 193 nm lithography, can be suitably used, such as those sold under the Epic™ brand, available from Dow Electronic Materials (Marlborough, Massachusetts). Suitable photoresists can be either positive-tone or negative-tone developing resists. After coating, the photoresist layer is then imaged (exposed) using patterned actinic radiation, and then developed using an appropriate developer to produce a patterned photoresist layer. The pattern is then transferred from the photoresist layer to the underlayer by an appropriate etching technique. Typically, the photoresist is also removed during such an etching process. The pattern is then transferred to the substrate by a suitable etching technique known in the art, for example, plasma etching, and the underlayer is removed. After the substrate is patterned, the underlayer is removed using conventional techniques. The electronic device substrate is then processed according to conventional means.

[0054] The cured underlayer can be used as the bottom layer in a multi-layer resist method. In such a method, a layer of the coating composition is coated on a substrate as described above and cured. Next, one or more central layers are coated on the aromatic underlayer. For example, a silicon-containing layer or hard mask layer is coated directly on the aromatic underlayer. A typical silicon-containing layer, such as a silicon-BARC, can be deposited by spin-coating on the underlayer and then curing, or an inorganic silicon layer, such as SiON, SiN, or SiO2, can be deposited on the underlayer by chemical vapor deposition (CVD). Any suitable hard mask can be used, deposited on the underlayer by any suitable technique, and cured as needed. Optionally, an organic BARC layer can be deposited directly on the silicon-containing layer or hard mask layer and appropriately cured. Next, a photoresist, such as a photoresist used in 193 nm lithography, is coated directly on the silicon-containing layer (in a three-layer method) or directly on the organic BARC layer (in a four-layer method). The photoresist layer is then imaged (exposed) using patterned actinic radiation, and then developed using an appropriate developer to produce a patterned photoresist layer. The pattern is then transferred from the photoresist layer to the layer directly below it using an appropriate etching technique known in the art, such as plasma etching, resulting in a patterned silicon-containing layer in a three-layer method and a patterned organic BARC layer in a four-layer method. When a four-layer method is used, the pattern is transferred from the organic BARC layer to the silicon-containing layer or hard mask layer using an appropriate pattern transfer technique, such as plasma etching. After the silicon-containing layer or hard mask layer is patterned, the aromatic underlayer is then patterned using an appropriate etching technique, such as O2 or CF4 plasma. Any remaining patterned photoresist and organic BARC layer are removed during the etching of the aromatic underlayer. The pattern is then transferred to the substrate, for example, using an appropriate etching technique, and any remaining silicon-containing layer or hard mask layer is removed, followed by removal of any remaining patterned aromatic underlayer, resulting in a patterned substrate.

[0055] The cured underlayer of the present invention can also be used in a self-aligning double patterning method. In such a method, a layer of the present coating composition is coated onto a substrate, for example, by spin coating. Any remaining organic solvent is removed, and the coating composition layer is cured to form a cured underlayer. A suitable central layer, such as a silicon-containing layer, is then coated onto the cured underlayer. A layer of a suitable photoresist is then coated onto the central layer, for example, by spin coating. The photoresist layer is then imaged (exposed) using patterned actinic radiation, and the exposed photoresist layer is then developed using a suitable developer to provide a patterned photoresist layer. The pattern is then transferred from the photoresist layer to the central layer and the cured underlayer by an appropriate etching technique, exposing a portion of the substrate. Typically, the photoresist is also removed during such an etching step. A silicon-containing conformal layer is then placed onto the patterned cured underlayer, exposing a portion of the substrate. Such silicon-containing layers are typically inorganic silicon layers, such as SiON, SiN, or SiO2, conventionally deposited by CVD. Such conformal coating results in a silicon-containing layer over the exposed portions of the substrate surface and over the pattern of the underlying layer, i.e., such silicon-containing layer substantially covers the sides and top of the patterned underlying layer. The silicon-containing layer is then partially etched (deburred) to expose the upper surface of the patterned polyarylene resin underlying layer and a portion of the substrate. After this partial etching step, the pattern on the substrate includes a plurality of features, each of which includes a line or pillar of the hardened underlying layer, with the silicon-containing layer immediately adjacent to the side of each feature of the hardened underlying layer. The hardened underlying layer is then removed, such as by etching, to expose the substrate surface that was under the pattern of the hardened underlying layer, providing a patterned silicon-containing layer on the substrate surface, where such patterned silicon-containing layer is doubled (i.e., doubled in lines and / or pillars) compared to the patterned hardened underlying layer.

[0056] The coating compositions of the present invention are also useful for forming planarizing layers, gap-filling layers, and protective layers in the manufacture of integrated circuits. When used as such planarizing, gap-filling, or protective layers, one or more intervening layers of material, such as a silicon-containing layer, another aromatic resin layer, or a hard mask layer, typically exist between the cured layer of the coating composition and any photoresist layer. Typically, such planarizing, gap-filling, and protective layers are ultimately patterned. A gap-filling method according to the present invention includes the steps of: (a) providing a semiconductor substrate having a relief image on its surface containing a plurality of gaps to be filled; and (b) applying a gap-filling composition onto the relief image, wherein the gap-filling composition is a compound represented by the formula (1):

[0057] [ka]

[0058] (wherein Z is a covalent chemical bond or O, C(=O), S, S(=O), S(=O), N(R), C 1-100 -hydrocarbylene, substituted C 1-100 -hydrocarbylene, -O-(C 1-20 -alkylene-O-) m1 , -O-(C 5-60 -arylene-O-) m2 and C(R 3 )(R 4 ) is a divalent linking group selected from; 1-20 -Alkyl, C 5-30 -aryl and C 2-20 - selected from unsaturated aliphatic moieties; each R 1 and each R 2 are independently H, OR, C 1-30 -hydrocarbyl, substituted C 1-30 -hydrocarbyl, -C(=O)-OR 5 , SR, S(=O)R, S(=O)2R, N(R 5 )(R 6 ) and N(R 7 )C(=O)R 5 Selected from; 1 R 1 and one R 2and Z together with the atoms to which they are attached can form a 5- or 6-membered ring; R 3 and R 4 are independently, C 1-20 -Alkyl and C 5-30 -aryl; R 3 and R 4 may, together with the carbons to which they are attached, form a 5- or 6-membered ring which may be fused to one or more aromatic rings and which may be optionally substituted; R 5 and R 6 are independently, C 1-20 -Alkyl or C 5-30 -aryl; R 7 is H or R 6 and;R 5 and R 6 can form a 5- or 6-membered ring together with the atom to which they are attached; each of a1 and a2 is 0 to 5; each of m1 and m2 is 1 to 100; and n is 2 to 1000). and one or more organic solvents, and (c) heating the gap-fill composition to a temperature that cures the one or more curable compounds, wherein the composition substantially fills, preferably fills, and more preferably completely fills a plurality of gaps in the semiconductor substrate.

[0059] The compounds of the present invention have good gap-filling properties. Films formed from the compounds of the present invention have good planarization and solvent resistance. [Example]

[0060] Example 1. Monomer M-1 (4.66 g, 10 mmol) was dissolved in 41.71 g of ethyl lactate. To this solution, 0.23 g (0.5 mmol) of di-μ-hydroxo-bis-[(N,N,N',N'-tetramethylethylenediamine)copper(II)] chloride (Cu-TMEDA) was added, and the reaction mixture was stirred at room temperature in air for 24 hours. The mixture was slowly added to a mixture of 1 M hydrochloric acid and methanol (200 mL, v / v = 20 / 80). The precipitated product was collected by filtration and then redissolved in ethyl acetate. Next, the solution was slowly added to methanol, and the precipitated product was collected and dried at 65 °C under vacuum for 2 days. Polymer P-1A (3.2 g) was obtained in 69% yield. GPC: M w = 1.9K, PDI = 1.4. This reaction is shown in Reaction Scheme 1.

[0061] Example 2. The procedure of Example 1 was repeated as follows: Monomer M-1 (4.66 g, 10 mmol) was dissolved in 43.80 g of ethyl lactate. 0.46 g (1.0 mmol) of Cu-TMEDA was added to this solution, and the reaction mixture was stirred in air at room temperature for 24 hours. The mixture was slowly added to a mixture of methanol containing 1 M hydrochloric acid (200 mL, v / v = 20 / 80). The precipitated product was collected by filtration and then redissolved in ethyl acetate. The solution was then slowly added to methanol, and the precipitated product was collected and dried at 65 °C under vacuum for 2 days. Polymer P-1B (3.61 g) was obtained in 78% yield. GPC: M w = 3.6K, PDI = 1.5. This reaction is shown in Reaction Scheme 1.

[0062] Reaction Scheme 1 [ka]

[0063] Example 3. Monomer M-2 (4.51 g, 10 mmol) was dissolved in 44.73 g of ethyl lactate. 0.46 g (1.0 mmol) of Cu-TMEDA was added to this solution, and the reaction mixture was stirred in the open air at room temperature for 24 hours. The mixture was slowly added to a mixture of methanol containing 1 M hydrochloric acid (200 mL, v / v = 20 / 80). The precipitated product was collected by filtration and then redissolved in ethyl acetate. The solution was then slowly added to methanol, and the precipitated product was collected and dried at 65 °C under vacuum for 2 days to produce polymer P-2 (3.79 g) in 84% yield. GPC: M w = 2.2K, PDI = 1.6. This reaction is shown in Reaction Scheme 2.

[0064] Reaction Scheme 2 [ka]

[0065] Example 4. Monomer M-3 (3.94 g, 10 mmol) was dissolved in 17.64 g of ethyl lactate. 0.46 g (1.0 mmol) of Cu-TMEDA was added to this solution, and the reaction mixture was stirred in air at room temperature for 24 hours. The mixture was slowly added to a mixture of methanol containing 1 M hydrochloric acid (200 mL, v / v = 20 / 80). The precipitated product was collected by filtration and then redissolved in ethyl acetate. The solution was then slowly added to methanol, and the precipitated product was collected and dried at 65 °C under vacuum for 2 days, resulting in 3.10 g of polymer P-3 in a 79% yield. GPC: M w = 195K, PDI = 19. This reaction is shown in Reaction Scheme 3.

[0066] Reaction Scheme 3 [ka]

[0067] Example 5. Monomer M-4 (6.35 g, 10 mmol) was dissolved in 27.25 g of ethyl lactate. 0.46 g (1.0 mmol) of Cu-TMEDA was added to this solution, and the reaction mixture was stirred in air at room temperature for 24 hours. The mixture was slowly added to a mixture of methanol containing 1 M hydrochloric acid (200 mL, v / v=20 / 80). The precipitated product was collected by filtration and then redissolved in ethyl acetate. The solution was then slowly added to methanol, and the precipitated product was collected and dried at 65° C. under vacuum for 2 days to produce 5.31 g of polymer P-4 in an 83% yield. GPC: M w = 3.0 K, PDI = 1.5. This reaction is shown in Reaction Scheme 4.

[0068] Reaction Scheme 4 [ka]

[0069] Example 6: Solubility. Solubility was measured by mixing the compounds of the present invention with PGME and PGMEA at 5% solids. The mixtures were visually inspected and examined using a turbidity meter (Orbeco-Hellige Co). If the turbidity value is less than 1, the compound is rated as soluble ("S"), and if the turbidity value is greater than 1, it is rated as not soluble ("NS"). The results are recorded in Table 1. As can be seen from these data, all of the compounds of the present invention are soluble in PGME and PGMEA, respectively.

[0070] [Table 1]

[0071] Example 7: Thermal Stability. The thermal stability of the compounds of the present invention was measured using a TA-Instrument Thermogravimetric Analyzer (TGA) Q500 under the following conditions: N2 at 10°C / min increments up to 700°C, and air at 10°C / min increments up to 700°C. The temperature at which the materials lost 5% of their weight ("Td5% ") are recorded in Table 2.

[0072] [Table 2]

[0073] Example 8. Solvent strip resistance was measured as an indication of film crosslinking. Compositions of the inventive compounds were prepared in PGMEA at 4.5% solids. Each composition was spin-coated onto an 8-inch (200 mm) silicon wafer at 1500 rpm using an ACT-8 Clean Track (Tokyo Electron Limited), followed by baking at 350°C for 60 seconds to form a film. The initial film thickness was measured using an OptiProbe™ manufactured by Therma-Wave Co. A commercial remover, PGMEA, was then applied to each film for 90 seconds, followed by a post-stripping bake step at 105°C for 60 seconds. The thickness of each film after post-stripping bake was measured again to determine the amount of film thickness loss. The difference in film thickness before and after contact with the remover is recorded in Table 3 as a percentage of the remaining film thickness. As can be seen from the data, films formed from the inventive polymers P-3 and P-4 retained more than 99% of their thickness after contact with the remover.

[0074] [Table 3]

[0075] Example 9. Polymers of the present invention were measured to determine their gap-filling properties. Gap-filling templates were made at CNSE Nano-FAB (Albany, NY). The templates had a 100 nm SiO2 film thickness and various pitches and patterns. Before coating the coupons with the compositions, the template coupons were baked at 150°C for 60 seconds as a dehydration bake. Each coating composition (4.5% solids in PGMEA) was coated onto the template coupons using an ACT-8 Clean Track (Tokyo Electron Limited) spin coater at a spin speed of 1500 rpm + / - 200 rpm. The target film thickness was 100 nm after curing, and the composition dilution was adjusted accordingly to achieve approximately the target film thickness after curing. The films were cured by placing the wafers on a hot plate at 350°C for 60 seconds. Cross-sectional scanning electron microscope (SEM) images of the coated coupons were collected using a Hitachi S4800 SEM (Hitachi High-Technologies Corporation). The planarization quality of the films was obtained from SEM images using Hitachi offline CD measurement software or CDM software by measuring the difference between the film thickness over the vias and the film thickness over the grooves (ΔFT). Films with a ΔFT < 20 nm were considered to have "good" planarization, and films with a ΔFT > 20 nm were considered to have "poor" planarization. Gap filling was assessed by visually inspecting the SEM images for any voids or bubbles within the groove pattern. Films without voids within the groove pattern were considered to have "good" gap filling, and films with voids within the groove pattern were considered to have "poor" gap filling. These results are recorded in Table 4.

[0076] [Table 4]

Claims

1. 1. A coating composition comprising a polymer and an organic solvent, The polymer has formula (1'): 【Chemistry 1】 (Wherein Z is —O—(C ５－６０ -arylene-O-) ｍ２ where Z is —O—(1,4-phenylene-O—) ｍ２ R is H, C １－２０ -Alkyl, C ５－３０ -aryl and C ２－２０ - unsaturated aliphatic moieties; each R １ and each R ２ are independently H, OR, C １－３０ -hydrocarbyl, substituted C １－３０ -hydrocarbyl, -C(=O)-O-R ５ ,SR,S(=O)R,S(=O) ２ R, N (R ５ ) (R ６ ) and N(R ７ ) C(=O)R ５ is selected from: R ５ and R ６ are independently １－２０ - alkyl or C ５－３０ -aryl; R ７ is H or R ６ and R ５ and R ６ can form a 5- to 6-membered ring together with the atoms to which they are attached; each of a1 and a2 is 0 to 5; m2=1; and n=2 to 1000). A coating composition comprising a repeating unit of

2. The repeating unit of formula (1') is of the formula: 【Chemistry 2】 and 【Transformation 3】 The coating composition of claim 1 selected from:

3. 3. The coating composition of claim 1, further comprising a curing agent and / or a surface leveling agent.

Images