초록 |
Currently, flexible electronics are at the high level of industrial and academic interest because of their potential for being very thin, light weight, less-breakable, and amenable to bio-implantable or wearable devices in comparison to devices built on the conventional rigid Si or glass substrates. Ease access to flexible electronics possibly extends their potential applications to flexible displays, batteries, and electrodes. Especially, flexible memory is the fundamental component for data processing, information storage, and radio frequency communication in the flexible electronics systems. Up to now, most studies on phase change random access memory (PRAM) have focused on the conventional bulk silicon technology except for a few elegant approaches Therefore, there is still a big challenge to improve performance efficiency of the flexible PRAM. Here, we present a novel approach based on the self-assembly of a block copolymer (BCP) to form a thin nanostructured SiOx layer which locally blocks the contact between a heater electrode and a phase-change material on flexible substrates or not. The writing current decreases by 5 times (corresponding to a power reduction of 1/20) as the occupying area fraction of SiOx nanostructures increases from a fill factor of 9.1 % to 63.6 %. Simulation results theoretically explain the current reduction mechanism by the localized switching of BCP-blocked phase change materials. Based on these results, we applied this BCP self-assembly process to plastic substrates for the fabrication of one diode-one resistor (1D-1R) structure flexible PRAM. This work can create a new chance of practical methodology to realize the nonvolatile memory for the flexible electronic applications. |