GeTe ultrathin film based phase-change memory with extreme thermal stability, fast SET speed, and low RESET power energy

Abstract

We designed the phase-change memory (PCM) cell based on ultrathin GeTe film (∼10 nm) and homemade nanoscale electrode filling craft to improve data retention ability and reduce programming energy, respectively. It was found that the temperature for ten years’ data retention of this ultrathin GeTe film is 160 ± 32.8 °C, which is much higher than that of conventional Ge2Sb2Te5 (GST, 83 ± 20.6 °C) film. Benefit to the nature of fragile-to-strong crossover behavior in GeTe supercooled liquids that was confined in a two-dimension structure, a fast SET speed of 6 ns is also detected in this ultrathin GeTe PCM. Moreover, the RESET power consumption of this ultrathin GeTe PCM is measured as 1.8 ± 0.5 nJ, and it is much lower than that of GST PCM (16.5 ± 1.5 nJ), which is attributed to the nanoscale electrode of the devices. The above-mentioned improvements enable the application of ultrathin GeTe PCM in neuromorphic computing.