Conductive polymer patterned media fabricated by diblock copolymer lithography for scanning multiprobe data storage

Abstract
A conductive polymer dot pattern has been fabricated as a patterned medium using diblock copolymer lithography (DCL) for scanning multiprobe data storage systems (SMDSSs). DCL can easily provide a higher dots pattern density than that obtained using electron beam lithography. For DCL, the microphase-separated structure of polystyrene-block-polymethylmethacrylate is utilized. Then, the closed dot pattern of polyaniline (PANI) with a center to center distance of adjacent dots of 30 nm is fabricated by DCL. Electrical modification experiments of the fabricated PANI dots are demonstrated using scanning probe microscopy (SPM). As a result, the conductivities of the modified dots are selectively changed by applying modification voltages with the tip of the SPM probe. Recording on the conductive polymer with 30 nm pitch at the minimum can be demonstrated, which corresponds to a recording density of ∼700 Gbits inch(-2). These results show that the conductive polymer patterned medium has the potential ability to achieve high-density recording for SMDSSs.