Guanidinium-based polyionic liquids and their use as additives for chemical mechanical planarization slurries

A guanidinium-based polymer or copolymer comprising more than one monomers containing at least one guanidinium group having a structure of:

• wherein:
• P1 denotes a polymerizable group and is selected from the group consisting of styrene (or vinyl benzene), acrylate or methacrylate, vinyl ether, allyl ether, acrylamide or methacrylamide, ethylene oxide, propylene oxide, maleimides, siloxane, norbornene, a group containing C═C double bonds, and combinations thereof,
• Sp1 denotes a spacer group;
• preferably Sp1 has a substituted or unsubstituted aliphatic moiety with a single bond at two terminal ends thereof;
• R1 is H, or a substituted or unsubstituted aliphatic moiety wherein CH2 may be replaced by O, S or N in a way that no heteroatoms are connected to each other;
• R2 is H, or a substituted or unsubstituted aliphatic moiety;
• preferably R2 is H, CH3, or CH2—CH3;
• R3 is H, or a substituted or unsubstituted aliphatic moiety;
• wherein two R3 groups can form a bridge between the nitrogen atoms building a five-, six- or seven-membered ring;
• X− denotes an anionic counterion and is selected from the group consisting of halide (F−, Cl−, Br−, or I−), BF4—, PF6—, carboxylate, malonate, citrate, carbonate, fumarate, MeOSO3—, MeSO3—, CF3COO, CF3SO3—, nitrate, and sulfate, wherein Me is methyl;
• and
• the guanidinium-based polymer or copolymer is water soluble.