Tunable Film Morphologies of Brush−Linear Diblock Copolymer Bearing Difluorene Moieties Yield a Variety of Digital Memory Properties

Abstract

An amphiphilic brush-linear diblock copolymer bearing a rigid difluorene moiety was synthesized, yielding a copolymer with a high thermal stability and excellent processability. The immiscibility of the blocks induced the formation of a variety of nanostructures, depending on the fabrication conditions, which differed significantly from the nanostructures observed among common diblock copolymers in similar composition. Interestingly, the orientations of the nanostructures could be controlled. The nanostructured polymer displayed a variety of tunable morphologies that yielded distinct electrical memory properties when incorporated as the active layer into a digital memory device. The memory devices could be operated under very low power consumption levels and displayed excellent unipolar switching properties.