A composition for forming an organic film contains a polymer having a partial structure shown by the following general formula (1) as a repeating unit, and an organic solvent. Each of AR1 and AR2 represents a benzene ring or naphthalene ring which optionally have a substituent; W.sub.1 represents a particular partial structure having a triple bond, and the polymer optionally contains two or more kinds of W.sub.1; and W.sub.2 represents a divalent organic group having 6 to 80 carbon atoms and at least one aromatic ring. This invention provides: a polymer curable even under film formation conditions in an inert gas and capable of forming an organic film which has not only excellent heat resistance and properties of filling and planarizing a pattern formed in a substrate, but also favorable film formability onto a substrate with less sublimation product; and a composition for forming an organic film, containing the polymer. ##STR00001##

A composition for resist underlayer film formation, includes: a polysiloxane compound including a first structural unit represented by formula (1); and a solvent. X represents an organic group comprising at least one structure selected from the group consisting of a hydroxy group, a carbonyl group, and an ether bond; a is an integer of 1 to 3, wherein in a case in which a is no less than 2, a plurality of Xs are identical or different from each other; R.sup.1 represents a halogen atom, a hydroxy group, or a monovalent organic group having 1 to 20 carbon atoms, wherein is a group other than X; and b is an integer of 0 to 2, wherein in a case in which b is 2, two R.sup.1s are identical or different from each other, and wherein a sum of a and b is no greater than 3.

##STR00001##

To provide a negative type photosensitive composition curable at a low temperature and capable of forming a cured film excellent in transparency, in chemical resistance and in environmental durability, and also to provide a pattern-formation method employing the composition. [Means] The present invention provides a negative type photosensitive composition comprising: an alkali-soluble resin, a compound having two or more (meth)acryloyloxy groups, a polysiloxane, a polymerization initiator, and a solvent. The alkali-soluble resin is a polymer comprising a carboxyl-containing polymerization unit and an alkoxysilyl-containing polymerization unit.

Provided are a coating composition for producing an interlayer insulation film, the coating composition making it possible to produce an interlayer insulation film patterned and having a high Young’s modulus and a low relative dielectric constant in high throughput, a method for producing the interlayer insulation film, and a semiconductor element including the interlayer insulation film. Specifically, the coating composition for producing the interlayer insulation film includes: a polymerizable compound (A) being a polymerizable silicon compound having two or more polymerizable groups, at least one of the two or more polymerizable groups being a polymerizable group Q expressed by *-O-R-Y (wherein * represents a bond with a silicon atom, R represents a single bond, an unsubstituted or substituted alkylene group having 1 to 12 carbon atoms and optionally containing a heteroatom, or a phenylene group, and Y represents a polymerizable group); and a photopolymerization initiator (B).

Provided are a photoacid generator, a photoresist composition including the same, and a method of forming a pattern by using the photoacid generator. The photoacid generator includes a copolymer of a monomer that generates an acid upon exposure to light and an acid-labile monomer of which solubility with respect to a developing solvent is changed by decomposition by an acid, wherein the copolymer is represented by Formula 1:

##STR00001## wherein, in Formula 1, x, y, L, A.sup.−, B.sup.+, R.sub.1, R.sub.2, and R.sub.3 are each the same as described in the detailed description.

An organic film forming composition, containing: a material shown by formula (I) and/or (II); and an organic solvent, where R.sub.1 and R.sub.4 each represent a hydrogen atom, an allyl or propargyl group, R.sub.2 and R.sub.5 each represent a substituent, R.sub.3 and R.sub.6 represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkynyl group having 2 to 4 carbon atoms, or an alkenyl group having 2 to 4 carbon atoms. “m” and “i” represent 0 or 1, “k” and “q” represent an integer of 0 to 2, “n” represent 1 or 2, “h”, and “j” represent an integer of 0 to 2 and satisfy the relationship 1≤h+j≤4, and “1” and “r” represent 0 or 1. W represents a single bond or divalent group shown by formulae (3). Each V independently represents a hydrogen atom or linking moiety.

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The present invention provides a photosensitive resin composition and a cured film prepared therefrom. The photosensitive resin composition includes a mixture of two or more siloxane polymers having different dissolution rates with respect to an aqueous solution of tetramethylammonium hydroxide. The composition keeps high transparency and high sensitivity, which are advantages of a composition containing a siloxane polymer, and has excellent chemical resistance, thereby providing a cured film having excellent stability in a post-processing.

A method for producing a coated substrate includes applying a photocurable silicon-containing coating film-forming composition to an uneven substrate; and exposing the photocurable silicon-containing coating film-forming composition to light, wherein the photocurable silicon-containing coating film-forming composition comprises a hydrolyzable silane, a hydrolysate thereof, or a hydrolytic condensate thereof, wherein the hydrolyzable silane is a hydrolyzable silane of the following Formula (1):

R.sup.1.sub.aR.sup.2.sub.bSi(R.sup.3).sub.4−(a+b)  Formula (1)

wherein R.sup.1 is a functional group relating to photocrosslinking; R.sup.2 is an alkyl group and is bonded to a silicon atom via an Si—C bond; R.sup.3 is an alkoxy group, an acyloxy group, or a halogen group; a is an integer of 1; b is an integer of 0 to 2; and a+b is an integer of 1 to 3.

Provided is a photosensitive resin composition that includes: a silicone resin (A) having an epoxy group and/or a phenolic hydroxyl group; an alkyl phenol novolac resin (B) indicated by formula (B); and a photoacid generator (C).

##STR00001##

(In the formula, R.sup.51 is a C1-9 saturated hydrocarbyl group. R.sup.52 is a C10-25 saturated hydrocarbyl group. n.sup.1 and n.sup.2 are numbers that fulfil 0≤n.sup.1<1, 0<n.sup.2≤1, and n.sup.1+n.sup.2=1. m.sup.1 represents an integer from 0 to 3 and m.sup.2 represents an integer from 1 to 3.)

To provide a negative type photosensitive composition which is capable of forming a cured film having good light shielding properties and high reflectance. [Means for Solution] A negative type photosensitive composition comprising an alkali-soluble resin having a particular structure, a reflectance modifier, a polymerization initiator, and a solvent.