Tetracarboxylic acid diester compound, polyimide precursor polymer and method for producing the same, negative photosensitive resin composition, patterning process, and method for forming cured film

1. A polyimide precursor polymer comprising a structural unit shown by the following general formula (7), and a structural unit shown by the following general formula (8),

wherein in general formula (7), X 1 represents a tetravalent organic group selected from at least one of the following formulae:

wherein the dotted line represents a bond;

X 2 represents a divalent organic group; and R 1 represents a group shown by the following general formula (2),

Y 1 n Rf) k   (2)

wherein the dotted line represents a bond; Y 1 represents an organic group with a valency of k+1; Rf represents a linear, branched, or cyclic alkyl group having 1 to 20 carbon atoms or an aromatic group in which a part or all of hydrogen atoms is/are substituted with a fluorine atom(s), and provided that at least one hydrogen on a terminal carbon is substituted with a fluorine atom; “k” represents 1, 2, or 3; and “n” represents 0 or 1, and

wherein in general formula (8), X 3 represents a tetravalent organic group that is the same as or different from X 1 ; and R 2 and R 3 independently represent a hydrogen atom, a linear, branched, or cyclic alkyl group having 1 to 6 carbon atoms, or an organic group shown by the following general formula (9), provided that at least one of R 2 and R 3 is an organic group shown by the general formula (9),

wherein the dotted line represents a bond; R 4 represents a hydrogen atom or an organic group having 1 to 3 carbon atoms; R 5 and R 6 independently represent a hydrogen atom or an organic group having 1 to 3 carbon atoms; and “m” represents an integer of 2 to 10.

2. A method for producing the polyimide precursor polymer according to claim 1 , comprising

reacting a tetracarboxylic acid diester compound shown by the following general formula (1) with a diamine shown by the following general formula (10) and a tetracarboxylic acid diester compound shown by the following general formula (11),

H 2 N—X 2 —NH 2   (10)

3. A negative photosensitive resin composition comprising:

(A) the polyimide precursor polymer according to claim 1 ;

(B) a photo-radical initiator; and

(D) a solvent.

4. A patterning process comprising:

(1) applying the negative photosensitive resin composition according to claim 3 onto a substrate to form a photosensitive material film;

(2) exposing the photosensitive material film to a high energy beam having a wavelength of 190 to 500 nm or an electron beam via a photomask after a heat treatment; and

(3) performing development with a developer of an organic solvent.

5. The patterning process according to claim 4 , further comprising performing post-exposure bake between the exposing step and the development step.

6. A method for forming a cured film, comprising baking a film having a pattern formed by the patterning process according to claims 4 at 100 to 300° C. and post-curing the film.

7. A negative photosensitive resin composition comprising:

(A′) the polyimide precursor polymer according to claim 1 ;

(B) a photo-radical initiator;

(C) a crosslinking agent having two or more photo-polymerizable unsaturated linking groups per molecule; and

(D) a solvent.

8. A negative photosensitive resin composition comprising:

(A′) the polyimide precursor polymer according to claim 1 ;

(B′) a photo acid generator;

(C′) one or two or more crosslinking agents selected from an amino condensate modified with formaldehyde or formaldehyde-alcohol, a phenol compound having on average two or more methylol groups or alkoxymethylol groups per molecule, a polyhydric phenol compound in which a hydrogen atom of a phenolic hydroxyl group is substituted with a glycidyl group, a polyhydric phenol compound in which a hydrogen atom of a phenolic hydroxyl group is substituted with a substituent shown by the following formula (C-1), and a compound containing two or more nitrogen atoms having a glycidyl group as shown by the following formula (C-2),

wherein the dotted line represents a bond, Rc represents a linear, branched, or cyclic alkyl group having 1 to 6 carbon atoms, and “s” represents 1 or 2; and

(D) a solvent.