Abstract: An actinic ray-sensitive or radiation-sensitive resin composition containing (A) a resin having a polarity that increases by an action of an acid, (B) a photoacid generator, and an anion (P) which is one or more anions selected from the group consisting of NO3?, SO42?, Cl?, and Br?, in which a content of the anion (P) is from 0.01 ppb to 100 ppm with respect to a total mass of the actinic ray-sensitive or radiation-sensitive resin composition, an actinic ray-sensitive or radiation-sensitive film formed from the actinic ray-sensitive or radiation-sensitive resin composition, a pattern forming method, and a method for manufacturing an electronic device.

Abstract: A positive photosensitive resin composition for a low-temperature process includes an alkali-soluble phenolic resin, a compound with quinonediazide group, a mixed solvent and at least one additive. The mixed solvent includes a first solvent and a second solvent. The first solvent has a volatilization rate of more than 50 relative to a volatilization rate of butyl acetate of 100, and the second solvent has a boiling point between 150° C. and 200° C. The at least one additive has a molecular weight of 500-5000 and a structural unit as Formula (I), wherein R1 is selected from a group consisting of hydrogen, hydroxyl group, C1-C5 alkyl group, phenyl group, halogen atoms and cyano group, R2 is selected from a group consisting of hydrogen, acid radical, benzene and derivatives thereof, phenols, benzoic acid and derivatives thereof and aromatic heterocycles, and n is 10-80.

Abstract: A composition for forming a resist underlayer film that enables the formation of a desired resist pattern; and a method for producing a resist pattern and a method for producing a semiconductor device, each of which uses the composition for forming a resist underlayer film. (In formula (1), A1, A2, A3, A4, A5, and A6 each independently represent a hydrogen atom, methyl group, or ethyl group; Q1 represents a divalent organic group; R1 represents a tetravalent organic group; and R2 represents an alkenyl group or alkynyl group having 2-10 carbon atoms.) The film-forming composition contains a solvent and a polymer that has a unit structure given by formula (1).

Abstract: Provided is a negative photosensitive resin composition. The negative photosensitive resin composition contains a polymer and a photo-radical generator. The polymer includes a structural unit (I) represented by formula (I), shown below, and a structural unit (II) represented by formula (II), shown below. In formula (I), R1 to R3 each indicate, independently of one another, a hydrogen atom, an alkyl group, or an aromatic ring group, R1 to R3 may be bonded to form a ring, R4 indicates a hydrogen atom or an alkyl group, X indicates an alkylene group having a carbon number of 1 to 10, and m indicates 0, 1, or 2. In formula (II), R5 to R8 each indicate, independently of one another, a hydrogen atom, an alkyl group, or an aromatic ring group, R5 to R8 may be bonded to form a ring, and n indicates 0, 1, or 2.

Abstract: A multilayer structure for lithography patterning is provided. The multilayer structure includes a substrate, a bottom anti-reflective coating (BARC) layer over the substrate, and a photoresist layer over the BARC layer. The BARC layer includes a polymer and a hydrolysis promoting agent. The photoresist layer includes an organometallic dimer obtained by partial hydrolysis of a precursor organometallic compound comprising hydrolysable ligands.

Abstract: A method for preparing a semiconductor device structure is provided. The method includes forming a target layer over a semiconductor substrate, and forming an energy-sensitive layer over the target layer. The method also includes performing an energy treating process on the energy-sensitive layer to transform a portion of the energy-sensitive layer into a treated portion. An untreated portion of the energy-sensitive layer is surrounded by the treated portion. The method further includes removing the treated portion, and transferring a pattern of the untreated portion of the energy-sensitive layer to the target layer such that the semiconductor substrate is exposed.

Abstract: A pattern-forming method includes applying a first composition on a surface layer of a substrate to form a first coating film. The surface layer includes a first region which includes a metal atom, and a second region which includes a silicon atom. The first coating film is heated. A portion other than a portion formed on the first region or a portion other than a portion formed on the second region of the first coating film heated is removed, thereby forming a first lamination portion. A second composition is applied on the substrate on which the first lamination portion is formed to form a second coating film. The second coating film is heated or exposed. A portion other than a portion formed on the first lamination portion of the second coating film heated or exposed is removed, thereby forming a second lamination portion.

Abstract: A polymer, comprising a first repeating unit derived from a first monomer comprising a single ester acetal group, and a second repeating unit derived from a second monomer comprising a plurality of ester acetal groups.

Abstract: The invention relates to compounds that can be used in an organic electronic device as an active compound, in particular for use in electronic devices. The invention further relates to a method for producing the compounds according to the invention, and to electronic devices comprising same.

Abstract: According to the present invention, an actinic ray-sensitive or radiation-sensitive resin composition including a resin P having a repeating unit represented by General Formula (P1) and a compound that generates an acid having a pKa of ?1.40 or more upon irradiation with actinic rays or radiation; and a resist film, a pattern forming method, and a method for manufacturing an electronic device, each using the composition, are provided. Mp represents a single bond or a divalent linking group. Lp represents a divalent linking group. Xp represents O, S, or NRN1. RN1 represents a hydrogen atom or a monovalent organic group. Rp represents a monovalent organic group.

Abstract: Methods for making molecular sieves are provided. The molecular sieves are comprised of thin semiconductors films in which a plurality of apertures is defined. The apertures are non-circular, nanoscale openings with tapered sidewalls that selectively pass certain molecules, while discriminating against the passage of other molecules.

Abstract: Water-based compositions containing a low VOC coalescent, a latex or water-dispersible polymer, and a water-insoluble UV-VIS (preferably, ultraviolet) absorber.

Abstract: A cross-linked polymer including a structure wherein at least a portion of phenolic hydroxyl groups in the polymer is protected by a group represented by the following formula (1): wherein R1 represents an alkyl group having 1 to 5 carbons and n represents an integer from 1 to 5; and * represents a bond part of the phenolic hydroxyl group to a residue other than a hydrogen atom, and a structure wherein at least a portion of phenolic hydroxyl groups in the polymer is protected by a group represented by the following formula (2): wherein R2 represents a divalent saturated hydrocarbon group having 2 to 17 carbons, containing an aromatic ring; and * represents a bond part of the phenolic hydroxyl group to a residue other than a hydrogen atom, and the polymers are cross-linked to each other.

Abstract: A radiation-sensitive resin composition includes: an onium salt compound represented by formula (1?); a resin including a structural unit having an acid-dissociable group; and a solvent. EA is a substituted or unsubstituted (?+?)-valent organic group having 1 to 40 carbon atoms; Z+ is a monovalent radiation-sensitive onium cation; and ? and ? are each independently 1 or 2.

Abstract: A resist composition that generates an acid upon exposure and whose solubility in a developing solution is changed by action of an acid, the resist composition containing a base material component whose solubility in a developing solution is changed by action of an acid, and a compound represented by General Formula (e1) in which Rd01 represents a monovalent organic group and Rd02 represents a single bond or a divalent linking group

Abstract: A pattern forming method includes forming a resist film having a first region, a second region, and a third region, on a substrate, irradiating the first region with light or an energy ray in a first irradiation amount, and irradiating the second region with light or an energy ray in a second irradiation amount, the second irradiation amount being smaller than the first irradiation amount. The pattern forming method also includes dissolving the resist film of the first region by using first liquid, forming a coating film on a side surface of the resist film after the resist film of the first region is dissolved, and dissolving the third region by using second liquid that is different from the first liquid.

Abstract: Materials and methods to immobilize photoacid generators on semiconducting substrates are provided. PAG-containing monomers are copolymerized with monomers to allow the polymer to bind to a surface, and optionally copolymerized with monomers to enhance solubility to generate PAG-containing polymers. The PAG-containing monomers can be coated onto a surface, where the immobilized PAGs can then be used to pattern materials coated on top of the immobilized PAGs, allowing direct patterning without the use of a photoresist, thereby reducing process steps and cost. The disclosed materials and processes can be used to produce conformal coatings of controlled thicknesses.

Abstract: A photoresist underlayer composition, comprising a polymer comprising a repeating unit of formula (1): wherein Ar is a monocyclic or polycyclic C5-60 aromatic group, wherein the aromatic group comprises one or more aromatic ring heteroatoms, a substituent group comprising a heteroatom, or a combination thereof; R1 is hydrogen, substituted or unsubstituted C1-30 alkyl, substituted or unsubstituted C1-30 heteroalkyl, substituted or unsubstituted C3-30 cycloalkyl, substituted or unsubstituted C2-30 heterocycloalkyl, substituted or unsubstituted C2-30 alkenyl, substituted or unsubstituted C2-30 alkynyl, substituted or unsubstituted C6-30 aryl, substituted or unsubstituted C7-30 arylalkyl, substituted or unsubstituted C7-30 alkylaryl, substituted or unsubstituted C3-30 heteroaryl, or substituted or unsubstituted C4-30 heteroarylalkyl; and R2 is substituted or unsubstituted C1-30 alkyl, substituted or unsubstituted C1-30 heteroalkyl, substituted or unsubstituted C3-30 cycloalkyl, substituted or unsubstituted C2

Abstract: [Problem to be Solved] To Provide a method for producing an acid-decomposable polymer having a reduced metal ion content, which suppresses decomposition and deprotection of the acid-decomposable polymer. [Means to Solve the Problem] The method for producing an acid-decomposable polymer according to the present invention comprises the steps of: preparing a polymer solution comprising an acid-decomposable polymer; washing an acidic cation exchanger with an organic solvent until the water content in the organic solvent discharged from the acidic cation exchanger falls to 400 ppm or less; and passing the polymer solution through the washed acidic cation exchanger to reduce the metal ion content of the polymer.

Abstract: Provided herein is a dual cure resin useful for the production of an object by additive manufacturing, comprising or consisting essentially of: (a) a photoinitiator; (b) not more than 5, 10 or 20 ppm of a polyurethane catalyst (e.g., tin, tertiary amine, bismuth, zinc, zirconium, or nickel catalysts); (c) a polyol; (d) free (i.e., unblocked) polyisocyanate; and (e) blocked polyisocyanate, the isocyanate groups of which are blocked by reaction with an amine (meth)acrylate blocking agent. Methods of making an object with the resin are also provided.

Abstract: A positive resist composition comprising a base polymer comprising recurring units having a nitrogen-containing tertiary ester structure exhibits a high sensitivity, high resolution, low edge roughness (LER, LWR) and small size variation, and forms a pattern of good profile after exposure and development.

Abstract: The invention relates to a method for selecting compounds which can be used as additives in photopolymer formulations for producing light holographic media, and to photopolymer formulations which contain at least one softener which are selected according to the claimed method. The invention also relates to the use of photopolymer formulations for producing holographic media.

Abstract: There are provided a method of forming a resist pattern includes: a step (1) in which a resist composition containing a base component (A) that generates base upon exposure and exhibits increased solubility in an alkali developing solution by the action of acid is applied to a substrate to form a resist film; a step (2) in which the resist film 2 is subjected to exposure; a step (3) in which baking is conducted after the step (2); and a step (4) in which the resist film 2 is subjected to an alkali development, thereby forming a negative-tone resist pattern in which the unexposed portion 2b of the resist film 2 has been dissolved and removed, and the resist composition used in the step (1).

Abstract: A film includes base and a photosensitive layer formed on the base. The photosensitive layer substantially includes a first photosensitive agent, a second photosensitive agent, and a thermosol. The first photosensitive agent is water-soluble. The second photosensitive agent is an aromatic ketone compound or a benzoin ether compound. The method for manufacturing the film and the masking method using the film is also provided.

Abstract: A method for producing a semiconductor device includes the steps of: applying a composition for forming a resist underlayer film for EUV lithography including a novolac resin containing a halogen atom onto a substrate having a film to be fabricated for forming a transferring pattern and baking the composition so as to form a resist underlayer film for EUV lithography; and applying a resist for EUV lithography onto the resist underlayer film for EUV lithography, irradiating, with EUV through a mask, the resist underlayer film for EUV lithography and a film of the resist for EUV lithography on the resist underlayer film, developing the film of the resist for EUV lithography, and transferring an image formed in the mask onto the substrate by dry etching so as to form an integrated circuit device.

Abstract: A pattern forming method includes: (i) forming a film from a chemical amplification resist composition; (ii) exposing the film, so as to form an exposed film; and (iii) developing the exposed film by using an organic solvent-containing developer, wherein the chemical amplification resist composition contains: (A) a resin substantially insoluble in alkali; (B) a compound capable of generating an acid upon irradiation with an actinic ray or radiation; (C) a crosslinking agent; and (D) a solvent, a negative chemical amplification resist composition used in the method, and a resist film formed from the negative chemical amplification resist composition.

Abstract: A positive photosensitive siloxane composition comprising at least three types of following polysiloxanes (A), (B) and (C) obtained by hydrolyzing and condensing a silane compound represented by general formula (1) R1nSi (OR2)4-n, a diazonaphthoquinone derivative, and a solvent: a polysiloxane (A) such that if pre-baked the film thereof will be soluble in a 5 weight % TMAH aqueous solution and the solution rate of said film will be 1,000 ?/sec or less; a polysiloxane (B) such that if pre-baked the solution rate of the film thereof will be 4,000 ?/sec or more relative to a 2.38 weight % TMAH aqueous solution; and a polysiloxane (C) such that if pre-baked the solution rate of the film thereof will be between 200 and 3,000 ?/sec relative to a 2.38 weight % TMAH aqueous solution.

Abstract: Embodiments in accordance with the present invention encompass negative-tone, aqueous base developable, self-imagable polymer compositions useful for forming films that can be patterned to create structures for microelectronic devices, microelectronic packaging, microelectromechanical systems, optoelectronic devices and displays.

Abstract: A positive resist composition comprises a polymer comprising repeat units having formula (1) or (2). Herein denotes an aromatic hydrocarbon group, R1 is H, methyl or trifluoromethyl, R2 is H, C1-C12 alkyl or aromatic hydrocarbon group, R3 is C1-C12 alkyl, or R2 and R3 may bond together to form a ring, and a is 1 or 2. When used in the ArF lithography, the resist composition exhibits high resolution. When used in the EB image writing for mask processing, the resist composition exhibits high resolution and sensitivity sufficient to comply with high-accelerating-voltage EB irradiation, and high etch resistance.

Abstract: A composition for a resist underlayer film is provided. The composition has excellent storage stability and can form a resist underlayer film which has excellent adhesion to a resist film, can improve reproducibility of a resist pattern and is resistant to an alkaline liquid used in development and to oxygen asking during the removal of a resist. The composition comprises a hydrolyzate and/or a condensate of a silane compound of the following formula (A), R1bR2cSi(OR3)4-a??(A) wherein R1 is a monovalent organic group having at least one unsaturated bond, R2 individually represents a hydrogen atom, a halogen atom or a monovalent organic group, R3 individually represents a monovalent organic group, R1 is a group other than OR3, a is an integer of 1 to 3, b is an integer of 1 to 3, and c is an integer of 0 to 2, provided that a=b+c.

Abstract: According to one embodiment, an actinic-ray- or radiation-sensitive resin composition includes an arylsulfonium salt that when exposed to actinic rays or radiation, generates an acid, the arylsulfonium salt containing at least one aryl ring on which there are a total of one or more electron donating groups, the acid generated upon exposure to actinic rays or radiation having a volume of 240 ?3 or greater.

Abstract: The present disclosure provides a micro-composite material used in the fabrication of three-dimensional objects, and associated methods and systems. In one example, a micro-composite material used in the fabrication of a three-dimensional object can comprise micronized polymeric particles; a photocurable curing agent; and a dye present in the micro-composite material in an amount at from 0.0001 wt % to 0.1 wt %, the dye having a ?max between 350 nm and 800 nm.

Abstract: An actinic-ray- or radiation-sensitive resin composition comprises (A) a resin that when acted on by an acid, exhibits an increased solubility in an alkali developer, (B) a compound that when exposed to actinic rays or radiation, generates an acid, (C) a resin containing two or more resins (c) each having at least either a fluorine atom or a silicon atom, and (D) a solvent.

Abstract: A positive photosensitive siloxane composition containing: a polysiloxane (Ia), which is obtained by hydrolyzing and condensing the silane compound represented by RSi(OR1)3 in general formula (1) and the silane compound represented by Si(OR1)4 in general formula (2) in the presence of a basic catalyst, and a pre-baked film of which has a dissolution rate of 1,000 ?/second or less in a 5 wt % TMAH aqueous solution; a polysiloxane (Ib), which is obtained by hydrolyzing and condensing at least the silane compound represented by general formula (1) in the presence of an acid or basic catalyst, and a pre-baked film of which has a dissolution rate of 100 ?/second or more in a 2.38 wt % TMAH aqueous solution; and a diazonaphthoquinone derivative and solvent.

Abstract: The present application relates to a photoactive compound including an oxime ester group and a phosphonate group together, and a photosensitive resin composition comprising the same, the compound of the present application having excellent storage stability and high-temperature process characteristics.

Abstract: A positive resist composition includes: (A) a resin capable of increasing the solubility in an alkali developing solution by the action of an acid, including: (a1) a repeating unit selected from repeating units represented by following formulae (a1-1) to (a1-3); (a2) a repeating unit represented by a following formula (a2); and (a3) a repeating unit selected from repeating units represented by following formulae (a3-1) to (a3-4); (B) a compound capable of generating an acid upon irradiation with actinic ray or radiation; (C) a resin having at least one of a fluorine atom and a silicon atom, and being insoluble in an alkali developing solution; and (D) a solvent, wherein the formulae above are defined in the specification.

Abstract: The present invention relates to a photoactive compound having a novel structure and a photosensitive resin composition including the same, and the photoactive compound according to the present invention has excellent sensitivity due to efficient absorption to a UV light source by including a nitro group and a phosphonate structure, and has excellent retention rate, mechanical strength, heat resistance, chemical resistance and developing resistance by improving solubility of the photosensitive resin composition by excellent compatibility of the phosphonate structure and a binder resin. Therefore, the photosensitive resin composition according to the present invention is useful to cure a column spacer, an overcoat, a passivation material and the like of a liquid crystal display device, and is useful in view of a high temperature process property.

Abstract: There is disclosed a resist top coat composition, used in a patterning process onto a photoresist film, wherein a resist top coat is formed by using the resist top coat composition onto a photoresist film formed on a wafer, and then, after exposure, removal of the resist top coat and development of the photoresist film are performed to effect the patterning on the photoresist film, wherein the resist top coat composition contains a truxene compound having phenol groups shown by the following general formula (1). As a result, there is provided a resist top coat composition not only having an effect from an environment to a resist film reduced and effectively shielding an OOB light, but also reducing film loss of a resist pattern and bridging between patterns and having an effect to enhance sensitivity of the resist; and a patterning process using this.

Abstract: An actinic-ray-sensitive or radiation-sensitive resin composition which is capable of improving line edge roughness (LER) and inhibiting pattern collapse, a resist film and a pattern forming method each using the same, a method for preparing an electronic device, and an electronic device are provided. The actinic-ray-sensitive or radiation-sensitive resin composition contains: (A) a resin having repeating units having a structure represented by any one of the following general formulae (I-1) to (I-3), and repeating units containing at least one selected from the group consisting of a lactone structure, a sultone structure, and a cyano group; and (B) a compound that generates an acid by irradiation with actinic rays or radiations.

Abstract: Provided is a pattern forming method making it possible to obtain a pattern with less scums and watermark defects. The pattern forming method includes the steps of forming a film from an actinic-ray- or radiation-sensitive resin composition includes a resin (A) that exhibits an increased solubility in an alkali developer when acted on by an acid, a compound (B) that generates an acid when exposed to actinic rays or radiation, and a resin (C) containing at least one of a fluorine atom and a silicon atom, exposing the film to light, and developing the exposed film using a tetramethylammonium hydroxide solution whose concentration is less than 2.38 mass %.

Abstract: A positive type resist composition for use in liquid immersion exposure comprises: (A) a resin having a monocyclic or polycyclic cycloaliphatic hydrocarbon structure, the resin increasing its solubility in an alkali developer by an action of acid; (B) a compound generating acid upon irradiation with one of an actinic ray and a radiation; (C) an alkali soluble compound having an alkyl group of 5 or more carbon atoms; and (D) a solvent.

Abstract: Disclosed are a photosensitive resin composition for a color filter including (A) a colorant including a dye represented by the following Chemical Formula 1 and/or a dye represented by the following Chemical Formula 2, wherein in the following Chemical Formulae 1 and 2, each substituent is the same as described in the detailed description; (B) an acrylic-based binder resin; (C) a photopolymerizable monomer; (D) a photopolymerization initiator; and (E) a solvent, and a color filter using the same.

Abstract: A negative pattern is formed by coating a resist composition onto a substrate, the resist composition comprising a polymer comprising recurring units having an acid labile group-substituted hydroxyl group, an acid generator, an onium salt of perfluoroalkyl ether carboxylic acid, and an organic solvent, prebaking, exposing, baking, and developing in an organic solvent such that the unexposed region of film is dissolved away and the exposed region of film is not dissolved. In image formation via positive/negative reversal by organic solvent development, the resist film is characterized by a high dissolution contrast between the unexposed and exposed regions.

Abstract: A positive resist composition comprising a polymer having carboxyl groups substituted with an acid labile group having formula (1) exhibits a high contrast of alkaline dissolution rate before and after exposure, a high resolution, a good pattern profile and minimal edge roughness. In formula (1), A is —(CR22)m—, B is —(CR52)n—, R2 and R5 are hydrogen or alkyl, m and n are 1 or 2, R3 is alkyl, alkenyl, alkynyl or aryl, R6 is alkyl, alkoxy, alkanoyl, alkoxycarbonyl, hydroxyl, nitro, aryl, halogen, or cyano, and p is 0 to 4.

Abstract: A composition for a resist underlayer film is provided. The composition has excellent storage stability and can form a resist underlayer film which has excellent adhesion to a resist film, can improve reproducibility of a resist pattern and is resistant to an alkaline liquid used in development and to oxygen ashing during the removal of a resist. The composition comprises a hydrolyzate and/or a condensate of a silane compound of the following formula (A), R1bR2cSi(OR3)4-a??(A) wherein R1 is a monovalent organic group having at least one unsaturated bond, R2 individually represents a hydrogen atom, a halogen atom or a monovalent organic group, R3 individually represents a monovalent organic group, R1 is a group other than OR3, a is an integer of 1 to 3, b is an integer of 1 to 3, and c is an integer of 0 to 2, provided that a=b+c.

Abstract: A radiation-sensitive composition containing 1 to 80% by weight of a solid component and 20 to 99% by weight of a solvent. The solid component contains a compound B which has (a) a structure derived from a polyphenol compound A by introducing an acid-dissociating group to at least one phenolic hydroxyl group of the polyphenol compound A which is synthesized by a condensation between a di- to tetrafunctional aromatic ketone or aromatic aldehyde each having 5 to 36 carbon atoms with a compound having 1 to 3 phenolic hydroxyl groups and 6 to 15 carbon atoms, and (b) a molecular weight of 400 to 2000. The composition containing the compound B is useful as an acid-amplified, non-polymeric resist material, because it is highly sensitive to radiation such as KrF excimer lasers, extreme ultraviolet rays, electron beams, and X-rays, and provides resist patterns with a high resolution, high heat resistance, and high etching resistance.

Abstract: The present invention relates to a negative photoresist composition and a patterning method for device in which a photoresist pattern having a high sensitivity with a good reverse taper profile can be formed not only to realize an effective patterning of various thin films but also to facilitate removal of the photoresist pattern after the patterning. The photoresist composition comprises an alkali-soluble binder resin; a halogen-containing first photo-acid generator; a triazine-based second photo-acid generator; a cross-linking agent having an alkoxy structure; and a solvent.

Abstract: An actinic ray-sensitive or radiation-sensitive resin composition, and a resist film and a pattern forming method using the composition are provided, the composition including (A) a compound capable of decomposing by the action of an acid to increase the solubility of the resin (A) in an alkali developer; (B) a compound capable of generating an acid upon irradiation with an actinic ray or radiation; (C) a basic compound; and (D) a specific compound containing at least two specific alicyclic hydrocarbon groups each substituted with a hydroxyl group.

Abstract: A monomer has the Formula I: wherein R1, R2, and R3 are each independently a C1-30 monovalent organic group, and R1, R2, and R3 are each independently unsubstituted or include a halogen, nitrile, ether, ester, ketone, alcohol, or a combination comprising at least one of the foregoing functional groups; R4 includes H, F, C1-4 alkyl, or C1-4 fluoroalkyl; A is a single bond or a divalent linker group, wherein A is unsubstituted or substituted to include a halogen, nitrile, ether, ester, ketone, alcohol, or a combination comprising at least one of the foregoing functional groups; m and n are each independently an integer of 1 to 8; and x is 0 to 2n+2, and y is 0 to 2m+2.

Abstract: A sulfonium salt having a 4-fluorophenyl group is introduced as recurring units into a polymer comprising hydroxyphenyl (meth)acrylate units and acid labile group-containing (meth)acrylate units to form a polymer which is useful as a base resin in a resist composition. The resist composition has a high sensitivity, high resolution and minimized LER.