| Popis: |
Phase-change materials such as Ge-Sb-Te (GST) exhibiting amorphous and crystalline phases can be used for phase-change random access memories (PCRAM). GST-based PCRAM has been applied as a storage-class memory; however, its relatively low ON/OFF ratio and large Joule heat energy for the RESET process (amorphization) significantly limit the storage density. This study proposes a novel phase-change nitride, CrN, with a much wider programming window (ON/OFF ratio more than 105) and lower RESET energy (a 90 % reduction from GST). High-resolution transmission electron microscopy revealed a unique phase-change from low resistive cubic CrN into high resistive hexagonal CrN2 induced by the Soret-effect. The proposed phase-change nitride could greatly expand the scope of conventional phase-change chalcogenides and offer a new strategy for next-generation PCRAM, enabling a large ON/OFF ratio, low energy, and fast operation. |
