A resist composition which includes a polymer compound including a structural unit which is derived from an acrylic ester in which the hydrogen atom bonded to an α-position carbon atom may be substituted with a substituent and which has a lactone-containing cyclic group containing other electron withdrawing groups such as a cyano group at a side chain terminal, and a compound whose a conjugate acid has an acid dissociation constant (pKa) of less than 3.

According to one embodiment, a polymer material is disclosed. The polymer material contains a polymer. The polymer contains a first monomer unit having a lone pair and an aromatic ring at a side chain, and a second monomer unit including a crosslinking group at a terminal of the side chain, with its molar ratio of 0.5 mol % to 10 mol % to all monomer units in the polymer. The polymer material can be used for manufacturing a composite film as a mask pattern for processing a target film on a substrate. The composite film can be formed by a process including, forming an organic film on the target film with the polymer material, patterning the organic film, and forming the composite film by impregnating a metal compound into the patterned organic film.

A positive resist material contains a base polymer containing: a repeating unit having two carboxyl groups whose hydrogen atoms are substituted with two tertiary carbon atoms each bonded to a double bond or triple bond; and a repeating unit having an acid generator shown by any of the following formulae (b1) to (b3). Thus, the present invention provides: a positive resist material having higher sensitivity than conventional positive resist materials, and smaller dimensional variation; and a patterning process using this inventive positive resist material.

##STR00001##

A salt having a group represented by the formula (aa):

##STR00001##

wherein X.sup.a and X.sup.b independently each represent an oxygen atom or a sulfur atom,
the ring W represents a C3-C36 heterocyclic ring which has an ester bond or a thioester bond, said heterocyclic ring optionally further having an oxygen atom, a sulfur atom, a carbonyl group or a sulfonyl group each by which a methylene group has been replaced, and said heterocycilic ring optionally having a hydroxyl group, a cyano group, a carboxyl group, a C1-C12 alkyl group, a C1-C12 alkoxy group, a C2-C13 alkoxycarbonyl group, a C2-C13 acyl group, a C2-C13 acyloxy group, a C3-C12 alicyclic hydrocarbon group, a C6-C10 aromatic hydrocarbon group or any combination of these groups each by which a hydrogen atom has been replaced, and
* represents a binding position.

The radiation-sensitive resin composition contains: a polymer having a structural unit that includes an acid-labile group; and a compound represented by formula (1). In the formula (1), Ar.sup.1 represents a group obtained by removing (m+n+2) hydrogen atoms from an aromatic ring of an arene having 6 to 30 carbon atoms; —OH and —COO— are bonded at ortho positions to each other on a same benzene ring on Ar.sup.1; and R.sup.G represents a group represented by formula (V-1), a group represented by formula (V-2), a group including a lactone structure, a group including a cyclic carbonate structure, a group including a sultone structure, a group including a ketonic carbonyl group, a group including a thiocarbonate group, or a group including a group represented by formula (V-3), or the like. ##STR00001##

A resist underlayer film for lithography has high solubility in a resist solvent (solvent used in lithography) for expressing good coating film forming property and a smaller selection ratio of dry etching rate as compared with a resist. A resist underlayer film-forming composition containing a novolac resin containing a structure (C) obtained by a reaction of an aromatic ring of an aromatic compound (A) with a hydroxy group-containing aromatic methylol compound (B). The aromatic compound (A) may be a component constituting the structure (C) in the novolac resin. The hydroxy group-containing aromatic methylol compound (B) may be a compound of Formula (1):

##STR00001##

The hydroxy group-containing aromatic methylol compound (B) may be 2-hydroxybenzyl alcohol, 4-hydroxybenzyl alcohol, or 2,6-di-tert-butyl-4-hydroxymethyl phenol.

An extreme ultraviolet light generation system may include a laser system emitting first prepulse laser light, second prepulse laser light, and main pulse laser light in this order; a chamber including at least one window for introducing, into the chamber, the first prepulse laser light, the second prepulse laser light, and the main pulse laser light; a target supply unit supplying a target to a predetermined region in the chamber; and a processor controlling the laser system to irradiate the target with the first prepulse laser light, irradiate the target, having been irradiated with the first prepulse laser light, with the second prepulse laser light having a pulse time width longer than a pulse time width of the main pulse laser light, and irradiate the target, having been irradiated with the second prepulse laser light, with the main pulse laser light temporally separated from the second prepulse laser light.

An object of the present invention is to provide a treatment liquid for patterning a resist film and a pattern forming method, each of which can accomplish suppression of generation of defects on a pattern and reduction in bridge defects of the pattern at the same time. The pattern forming method of an embodiment of the present invention is a pattern forming method by forming a resist film on a substrate using a resist composition including at least a resin whose polarity increases by the action of an acid, a photoacid generator, and a solvent, exposing the resist film, and then treating the exposed resist film with a treatment liquid to form a pattern, in which the treatment liquid includes two or more organic solvents, a boiling point of at least one organic solvent of the two or more organic solvents is 120° C. to 155° C., a content of the organic solvent having a boiling point of 120° C. to 155° C. is 45% by mass or more with respect to the total mass of the treatment liquid, and a difference between the boiling point of the organic solvent having the highest boiling point and the boiling point of the organic solvent having the lowest boiling point among the two or more organic solvents is less than 49° C.

A chemically amplified positive resist composition is provided comprising (A) a sulfurane or selenurane compound having formula (A1) wherein M is sulfur or Selenium and (B) a base polymer containing a polymer comprising repeat units having formula (B1). The resist composition exhibits a high resolution during pattern formation and forms a pattern with improved LER and CDU.

##STR00001##

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.