Photo-patternable dielectric materials and formulations and methods of use

1. A method, comprising;

(a) forming on a substrate, a layer of a photoactive formulation comprising:

a photoacid generator;

a casting solvent; and

a silsesquioxane polymer, wherein said silsesquioxane polymer includes at least one monomer of the structure:

where wherein R 3 is selected from the group consisting of linear alkyl, branched alkyl and cycloalkyl moieties;

(b) patternwise exposing said layer with ultraviolet light to generate an exposed layer;

(c) baking said exposed layer to cross-link said silsesquioxane polymer in regions of said exposed layer exposed to said ultraviolet light to generate a baked layer;

(d) developing said baked layer to remove portions of said baked layer not exposed to said ultraviolet light to form a first trench in a developed layer;

(e) curing said developed layer to further cross-link said silsesquioxane polymer and form a patterned cured layer including said first trench; and

(f) filling said first trench in said patterned cured layer with an electrically conductive material.

2. The method of claim 1 , further including:

between (e) and (f):

forming an additional layer of a photoactive formulation on said patterned cured layer, said addition cured layer comprising:

a photoacid generator;

a casting solvent; and

a silsesquioxane terpolymer or a silsesquioxane quadpolymer;

patternwise exposing said additional layer with ultraviolet light to generate an additional exposed layer;

baking said additional exposed layer to cross-link said silsesquioxane terpolymer or said silsesquioxane quadpolymer in regions of said additional exposed layer exposed to ultraviolet light to generate an additional baked layer;

developing said additional baked layer to remove portions of said additional baked layer not exposed to ultraviolet light to form a second trench in an additional developed layer;

curing said additional developed layer to cross-link said silsesquioxane terpolymer or said silsesquioxane quadpolymer to form a patterned additional cured layer including said second trench, said first trench exposed in a bottom of said second trench, said substrate exposed in said bottom of said first trench; and

wherein (f) includes simultaneously filling said first trench and said second trench with said electrically conductive material.

3. The method of claim 2 , wherein said additional silsesquioxane polymer comprises three or four monomers of the structural formulas (1), (2), (3), (4):

wherein two of said three or four monomers are structures (1) and (2);

wherein R 1 is selected from the group consisting of linear alkyl, branched alkyl, cycloalkyl, aromatic, arene and ester moieties;

wherein R 2 is selected from the group consisting of vinyl, substituted-vinyl, acetylenic, substituted acetylenic and nitrile moieties;

wherein R 3 is selected from the group consisting of linear alkyl, branched alkyl and cycloalkyl moieties;

wherein R 4 is selected from the group consisting of linear alkoxy, branched alkoxy, cycloalkoxy, acetoxys, hydroxyl, silyloxy and silanol moieties; and

wherein m, n, o, and p represent the mole percent (mol %) of repeating units with m+n+o+p equal to or greater than about 40 mol % and wherein when only three monomers are present either o or p is zero.

4. The method of claim 1 , wherein said silsesquioxane polymer comprises three or four monomers of the structural formulas (1), (2), (3), (4):

wherein two of said three or four monomers are structures (1) and (2);

wherein R 1 is selected from the group consisting of linear alkyl, branched alkyl, cycloalkyl, aromatic, arene and ester moieties;

wherein R 2 is selected from the group consisting of vinyl, substituted-vinyl, acetylenic, substituted acetylenic and nitrile moieties;

wherein R 3 is selected from the group consisting of linear alkyl, branched alkyl and cycloalkyl moieties;

wherein R 4 is selected from the group consisting of linear alkoxy, branched alkoxy, cycloalkoxy, acetoxys, hydroxyl, silyloxy and silanol moieties; and

wherein m, n, o, and p represent the mole percent (mol %) of repeating units with m+n+o+p equal to or greater than about 40 mol % and wherein when only three monomers are present either o or p is zero.

5. The method of claim 1 , wherein said curing comprises simultaneous exposure to ultraviolet light and heating to a temperature of at least 400° C.

6. The method of claim 1 , wherein said silsesquioxane polymer consists essentially of monomers of structural formulas (1), (2), (3) and (4), R 1 is a methyl moiety and m is between about 70 mol % and about 80 mol %, R 2 is a vinyl moiety and n is between about 3 mol % and about 13 mol %, R 3 is an ethylene moiety and o is between about 0.5 mol % and about 6 mol %, and R 4 is a hydroxyl moiety and p is between about 2 mol % and about 10 mol %.

7. The method of claim 1 wherein said photoactive formulation further includes:

an additive silsesquioxane polymer of structure (5):

wherein R 5 is selected from the group consisting of alkyl, cycloalkyl and aryl moieties; and

wherein s is an integer between about 10 and about 1000.

8. The method of claim 1 , wherein photoactive formulation further includes:

one or more cross-linking agents, one or more organic bases or combinations thereof.

9. The method of claim 1 , wherein said silsesquioxane polymer comprises four monomers of the structural formulas (1), (2), (3), (4).

10. A method, comprising;

(a) forming on a substrate, a layer of a photoactive formulation comprising:

a photoacid generator;

a casting solvent;

a silsesquioxane polymer; and

an additive silsesquioxane polymer of structure (5):

wherein R 5 is selected from the group consisting of alkyl, cycloalkyl and aryl moieties; and

wherein s is an integer between about 10 and about 1000;

(b) patternwise exposing said layer with ultraviolet light to generate an exposed layer;

(c) baking said exposed layer to cross-link said silsesquioxane polymer in regions of said exposed layer exposed to said ultraviolet light to generate a baked layer;

(d) developing said baked layer to remove portions of said baked layer not exposed to said ultraviolet light to form a first trench in a developed layer;

(e) curing said developed layer to further cross-link said silsesquioxane polymer and form a patterned cured layer including said first trench; and

(f) filling said first trench in said patterned cured layer with an electrically conductive material.

11. The method of claim 10 , wherein said silsesquioxane polymer comprises three or four monomers of the structural formulas (1), (2), (3), (4):

wherein two of said three or four monomers are structures (1) and (2);

wherein R 1 is selected from the group consisting of linear alkyl, branched alkyl, cycloalkyl, aromatic, arene and ester moieties;

wherein R 2 is selected from the group consisting of vinyl, substituted-vinyl, acetylenic, substituted acetylenic and nitrile moieties;

wherein R 3 is selected from the group consisting of linear alkyl, branched alkyl and cycloalkyl moieties;

wherein R 4 is selected from the group consisting of linear alkoxy, branched alkoxy, cycloalkoxy, acetoxys, hydroxyl, silyloxy and silanol moieties; and

wherein m, n, o, and p represent the mole percent (mol %) of repeating units with m+n+o+p equal to or greater than about 40 mol % and wherein when only three monomers are present either o or p is zero.