Universal strategy for stabilizing ultrathin polymer films for spin-on doping applications

Stabilizing ultrathin films, in particular, avoiding dewetting is a critical requirement in electronics. To address this issue, a variety of approaches have been developed including self-assembled monolayers, surface-initiated polymerization, and end-functionalization of polymers. However, most of these approaches require either post-processing of the substrates or are applicable only to the specific combination of polymers and substrates. Herein, we introduce a mussel-inspired universal adhesive moiety, dopamine, as an end group to a boron-containing polymer, and demonstrate its application to spin-on doping on silicon. On semiconductor-relevant surfaces: Si-OH, SiO_x, TiN, and Si₃N₄, ca. 15-nm thick films with the dopamine end group are more thermally stable at 230 ^oC for 30 min, while the control polymer films with carboxyl end group severely dewet. In addition, dosage of silicon with the dopamine-functionalized polymer is comparable or higher than that with the control polymer, demonstrating one of the promising applications of such conformal coatings.