Thermally decomposable polymer compositions for forming microelectronic assemblies
A thermally decomposable polymer composition comprising a polyester of a dicarboxylic acid and a tertiary cyclohexanediols of Formulae V and VI are disclosed, which are useful in the forming of microelectronic assemblies: a representative example of a dicarboxylic acid is an oxalic acid and representative example of thermally decomposable polyester is the polyester of the formula: wherein m is at least about 100.
1. A sacrificial polymer composition comprising:
a thermally decomposable polymer comprising repeating units derived from an ester of a dicarboxylic acid selected from the group consisting of oxalic acid, malonic acid, succinic acid, glutaric acid and adipic acid and a difunctional tertiary alcohol selected from the group consisting of a compound of formula V and a compound of formula VI:
a thermally activated base generator, said thermally activated base generator comprising a cation selected from formula 1, 2, or 3:
where each R e is independently selected from hydrogen, a methyl or ethyl group, a linear, branched or cyclic C 3 -C 12 alkyl group; a linear, branched or cyclic C 3 -C 12 heteroalkyl group having from 1 to 4 heteroatoms independently selected from nitrogen, oxygen or sulfur; a C 6 -C 10 aryl group; a C 5 -C 10 heteroaryl group having from 1 to 4 heteroatoms independently selected from nitrogen, oxygen or sulfur; or where two R 1 groups are taken together with any intervening atoms to form one or more cyclic alkyl or heteroalkyl groups as previously defined, and where for formula 1, at least one R 1 is hydrogen; and
a carrier solvent selected from acetophenone, α-angelicalactone, γ-butyrolactone, n-butyl acetate, diethylene glycol dimethyl ether, ethyl 3-ethoxypropionate, ethyl lactate, 2-heptanone, methyl isobutyl ketone, γ-octanoic lactone and combinations thereof.
2. The composition according to claim 1 , wherein said difunctional tertiary alcohol is:
3. The composition according to claim 1 , wherein said difunctional tertiary alcohol is:
4. The composition according to claim 1 , wherein said polymer is of the formula:
wherein m is at least about 100.
5. The composition of claim 1 , which comprises one or more additives of the formula 1, 2 or 3 selected from tetrabutylammonium acetate (Bu 4 N OAc), tetraethylammonium tosylate (Et 4 N OTs), pyridinium triflate (PyH OTf) or a compound of the formula: