| 초록 |
Phase change memory (PCM), which exploits the phase change behavior of chalcogenide materials, affords outstanding advantages due to its high speed, excellent reliability, and great scalability. However, the high switching current of PCM has a critical obstacle to realize low-power operation, resulting from a physical limit of photolithography in resolution. Herein, we report a useful approach employing block copolymer (BCP) self-assembly process, leading to various nanostructures with small features from 10 nm to 50 nm. In particular, we present ring-shaped PCM devices (Pt/Ge2Sb2Te5(GST)/TiN) with small contact area between GST and TiN by using a self-assembled BCP nanostructure (dot-in-hole) as a template. The ring-shaped PCM cell arrays showed ultra-small writing current of ~ 2 µA. Simulation results support how different in switching currents for ring-type PCM compared to the pillar-type of PCM devices. We believe that this novel approach may also be extendable to other memory device applications such as a resistive switching memory and magnetic storage devices. |
