Selective spin-on deposition of polymers on heterogeneous surfaces

摘要

Selective deposition holds promise to simplify next-generation device fabrication and bring down economic cost. In thiswork, selectively depositing polymers on metal/dielectric patterns was achieved by spin dewetting, a phenomenon thatrefers to the dewetting of polymers during spin coating. Our strategy utilizes self-assembled monolayers (SAMs) to inducedewetting of polymers over some areas. Line patterns of Cu/SiO_2 were investigated. A hydrophobic SAM,octyltrichlorosilane (OTS, Cl_3Si–C_8H_(17)), was selectively formed on SiO_2 in the presence of Cu to render SiO_2 non-wettable.During a subsequent spin coating step, polymers dewet from OTS-functionalized SiO_2 and coat Cu exclusively. The spindewetting process is strongly dictated by the spin coating kinetics. A systematic study of the processing conditions revealedstrong dependence of polymer film coverage on spin speed, solution concentration, polymer molecular weight, castingsolvent, and SAM hydrophobicity.