A resist composition comprising a base polymer and a sulfonium or iodonium salt of a fluorinated sulfonic acid having a phenylene group which is substituted with an iodized phenyl-containing group and a nitro group is provided. The resist composition has a high sensitivity and forms a pattern with improved LWR or CDU, independent of whether it is of positive or negative tone.

Provided is a resin that exhibits high resist performance because a poorly soluble component with respect to a resist solvent is reduced, and a production method for the resin. Disclosed is a photoresist resin containing an acrylic resin, in which when the photoresist resin is dissolved in propylene glycol monomethyl ether acetate in such a way that a resin solid content concentration is 5 wt %, a polystyrene equivalent turbidity measured using a method described in “Drinking Water Testing Methods” of Japan Water Works Association of 2003, Ministry of Health, Labor and Welfare Ordinance No. 261 of Japan is 30 or less.

Provided are a salt capable of producing a resist pattern with satisfactory CD Uniformity (CDU), an acid generator, and a resist composition. Disclosed are a salt represented by formula (I), an acid generator, and a resist composition:

##STR00001##

wherein, in formula (I), R.sup.4, R.sup.5, R.sup.6, R.sup.7, R.sup.8 and R.sup.9 each represent a halogen atom, a haloalkyl group, etc.; A.sup.1, A.sup.2 and A.sup.3 each represent a hydrocarbon group, etc.; m1 and m4, m5, m6 and m7 represent an integer of 0 to 5, m2, m3, m8 and m9 represent an integer of 0 to 4, 0≤m1+m7≤5, 0≤m2+m8≤4, 0≤m3+m9≤4, and at least one of m1, m2 and m3 represents an integer of 1 or more; X.sup.4 represents a single bond, —CH.sub.2—, —O—, —S—, —CO—, —SO— or —SO.sub.2—; and AI.sup.− represents an organic anion.

[Object] To provide a negative type photosensitive composition developable with a low concentration alkali developer and capable of forming a cured film excellent in transparency, in chemical resistance and in environmental durability; and further to provide a pattern-formation method employing the composition. [Means] The present invention provides a negative type photosensitive composition comprising: (I) an alkali-soluble resin, namely, a polymer comprising a carboxyl-containing polymerization unit and an alkoxysilyl-containing polymerization unit, (II) a polysiloxane, (III) a compound having two or more (meth)acryloyloxy groups, (IV) (i) a silicone derivative having a particular structure and/or (ii) a compound having two or more epoxy groups, (V) a polymerization initiator, and (VI) a solvent.

New Te-zwitterion compounds are provided, including photoactive tellurium salt compounds useful for Extreme Ultraviolet Lithography.

A positive resist composition comprising a base polymer comprising recurring units (a) having the structure of an ammonium salt of a carboxylic acid having an iodized or brominated aromatic ring 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.

A radiation-sensitive resin composition contains: a polymer that includes a structural unit including an acid-labile group; and a radiation-sensitive acid generating agent. The radiation-sensitive acid generating agent includes a sulfonate anion and a radiation-sensitive cation. The sulfonate anion includes two or more rings, and an iodine atom and a monovalent group having 0 to 10 carbon atoms which includes at least one of an oxygen atom and a nitrogen atom bond to at least one of the two or more rings. The ring is preferably an aromatic ring. The radiation-sensitive acid generating agent is preferably a compound represented by formula (1). In the formula (1), A.sup.1 represents a group obtained from a compound which includes a ring having 3 to 20 ring atoms by removing (p+q+r+1) hydrogen atoms on the ring. ##STR00001##

A positive resist composition comprising a base polymer comprising recurring units (a) having the structure of an ammonium salt of N-carbonylsulfonamide having an iodized aromatic ring, and recurring units (b1) having an acid labile group-substituted carboxyl group and/or recurring units (b2) having an acid labile group-substituted phenolic hydroxyl group exhibits a high sensitivity, high resolution, low edge roughness and dimensional uniformity, and forms a pattern of good profile after exposure and development.

A salt represented by formula (I): ##STR00001##
wherein R.sup.1 and R.sup.2 each independently represent a hydroxy group, —O—R.sup.10, —O—CO—O—R.sup.10 or —O-L.sup.1-CO—O—R.sup.10; L.sup.1 represents an alkanediyl group having 1 to 6 carbon atoms; R.sup.4, R.sup.5, R.sup.7 and R.sup.8 each independently represent a halogen atom, an alkyl fluoride group having 1 to 12 carbon atoms or a hydrocarbon group having 1 to 18 carbon atoms, the hydrocarbon group may have a substituent, and —CH.sub.2— included in the hydrocarbon group may be replaced by —O—, —CO—, —S— or —SO.sub.2—; R.sup.10 represents an acid-labile group; X.sup.1 and X.sup.2 each independently represent an oxygen atom or a sulfur atom; m1 represents an integer of 1 to 5, m2 and m8 represent an integer of 0 to 5, m4, m5 and m7 represent an integer of 0 to 4; and AI.sup.− represents an organic anion.

It is an object of the present invention to provide a method of forming a high-contrast fine pattern onto a resist film. The present invention relates to a pattern forming method, comprising; applying a resist material onto a substrate to form a resist film, introducing a metal into the resist film, exposing, and developing. In addition, the present invention also relates to a resist material and a pattern forming apparatus.