Dynamic random access memory devices based on bismuth sulfide nanoplates prepared from a single source precursor

Abstract

Semiconducting bismuth sulfide (Bi₂S₃) nanoplates with unique highly oriented {001} surfaces were prepared on a large scale using a novel organic precursor Bi(DTCA)₃ (DTCA = carbazole-9-carbodithioic acid). The as-prepared Bi₂S₃ nanoplates were dispersed in dimethyl sulfoxide (DMSO) and spin-coated onto an indium tin oxide (ITO) coated glass substrate. With a simple ITO/Bi₂S₃/Al stacked structure, the fabricated sandwich-like memory device demonstrates dynamic random access memory (DRAM) characteristics with a maximum ON/OFF current ratio up to 10⁶ and a long retention time. It is suggested that the volatile nature of the memory device comes from the Schottky contact between the Bi₂S₃ nanoplates and the Al electrodes.