A positive resist composition is provided comprising (A) a resin comprising recurring units having adamantane ring and recurring units having cyclopentyl so that the resin may increase its alkali solubility under the action of acid, (B) a mixture of sulfonium salts, and (C) a solvent. By coating the resist composition as a resist film, forming a protective film thereon, and effecting immersion lithography, a pattern of good profile is formed at a high resolution.

A photoresist composition comprising: a resin (A1) which has an acid-labile group; a resin (A2) which comprises a structural unit represented by formula (I); ##STR00001##
wherein R.sup.1 represents a C1-C13 fluorinated saturated hydrocarbon group, A.sup.1 represents a single bond, a C1-C6 alkanediyl group, or *-A.sup.2-X.sup.1-(A.sup.3-X.sup.2).sub.a-(A.sup.4).sub.b-, and R.sup.2 represents a C1-C18 hydrocarbon group; and an acid generator.

An electrostatic substrate holder for use in an extreme ultraviolet radiation lithography system includes a substrate receiving surface having a plurality of gas passages in fluid communication with a variable gas pressure pump. Varying the pressure in a void space between the backside of the substrate and the substrate receiving surface of the substrate holder promotes removal of non-gaseous materials within the void space between the backside of the substrate and the substrate receiving surface of the substrate holder.

A photoresist composition containing (A) a polymer having a structural unit (I) that includes an acid-labile group, and (I) a compound represented by the following formula (1). In the following formula (1), R.sup.1, R.sup.2, R.sup.3 and R represent a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms. X represents a single bond, an oxygen atom or —NR.sup.a—. R.sup.a represents a hydrogen atom, a hydroxy group or a monovalent organic group having 1 to 20 carbon atoms, and optionally taken together represents a ring structure by binding with R each other. A.sup.− represents —SO.sub.3.sup.− or —CO.sub.2.sup.−. M.sup.+ represents a monovalent onium cation. ##STR00001##

A resist composition is provided comprising a polymer comprising recurring units (a) having a succinimide structure and recurring units (b) containing a group capable of polarity switch with the aid of acid. The resist composition suppresses acid diffusion, exhibits a high resolution, and forms a pattern of satisfactory profile with low edge roughness.

An immersion liquid is provided comprising an ion-forming component, e.g. an acid or a base, which has a relatively high vapor pressure. Also provided are lithography processes and lithography systems using the immersion liquid.

A resist pattern-forming method includes applying a photoresist composition directly or indirectly on a front face of a substrate to form a photoresist film. A topcoat layer is laminated directly or indirectly on a front face of the photoresist film. The photoresist film is subjected to liquid immersion lithography in a presence of a liquid immersion liquid on a front face of the topcoat layer. Part of the topcoat layer is removed after subjecting the photoresist film to the liquid immersion lithography. The photoresist film is developed after the part of the topcoat layer is removed.

Provided are chemically amplified resist compositions that include acid-labile sulfonate-ester photoresist polymers that are developable in an organic solvent. The chemically amplified resists produce high resolution positive tone development (PTD) and negative tone development (NTD) images depending on the selection of organic development solvent. Furthermore, the dissolution contrast of the traditional chemically amplified resists may be optimized for dual tone imaging through the addition of a photoresist polymer comprising an acid-labile sulfonate-ester moiety.

One embodiment of the present invention provides a pattern forming method including a step for forming an actinic ray-sensitive or radiation-sensitive film on a substrate using an actinic ray-sensitive or radiation-sensitive resin composition, a step for forming an upper layer film on the actinic ray-sensitive or radiation-sensitive film using a composition for forming an upper layer film, a step for exposing a laminate film including the actinic ray-sensitive or radiation-sensitive film and the upper layer film, and a step for developing the exposed laminate film using a developer including an organic solvent. The composition for forming an upper layer film contains a resin (XA), a resin (XB) containing fluorine atoms, a basic compound (XC), and a solvent (XD), and the resin (XA) is a resin not containing fluorine atoms, or in a case where the resin (XA) contains fluorine atoms, the resin (XA) is a resin having a lower content of fluorine atoms than that in the resin (XB), based on a mass.

A salt represented by formula (I): ##STR00001##
wherein R.sup.1 and R.sup.2 independently represent a hydrogen atom, a hydroxy group or a C.sub.1 to C.sub.12 hydrocarbon group in which a methylene group may be replaced by a —O— or —CO—; m and n independently represent 1 or 2; Ar represents an optionally substituted phenyl group; Q.sup.1 and Q.sup.2 independently represent a fluorine atom or a C.sub.1 to C.sub.6 perfluoroalkyl group, A.sup.1 represents a single bond, a C.sub.1 to C.sub.24 alkanediyl group or the like, and Y represents an optionally substituted C.sub.1 to C.sub.18 alkyl group or monovalent C.sub.3 to C.sub.18 alicyclic hydrocarbon group, and a methylene group therein may be replaced by a —O—, O— or —SO.sub.2—, provided that the alkyl group or the alicyclic hydrocarbon group has at least one substituent, or at least one methylene group contained therein is replaced by a —O—, —CO— or —SO.sub.2—.