斯科特基屏障的漂移 阶段变化的高度 材料
Rivka-Galya Nir-Harwood1, Guy Cohen2, Amlan Majumdar2
1Viterbi Faculty of Electrical & Computer Engineering, Technion-Israel Institute of Technology, Haifa 32000, Israel.
ACS nano
|March 8, 2024
概括
阶段变换内存 (PCM) 设备中的电阻漂移主要是由 Schottky 屏障在接口上的高度引起的,而不是批量效应. 这一发现对于开发稳定的神经形态计算硬件至关重要.
科学领域:
- 材料科学 材料科学 材料科学
- 电气工程 电气工程
- 计算机科学 计算机科学
背景情况:
- 阶段变换记忆 (PCM) 设备在神经形态计算中显示出多层记忆和人工突触的前景.
- 阻力漂移是一个主要的挑战,通常归因于材料中的散装效应.
- 了解电阻漂移的起源对于推进PCM技术至关重要.
研究的目的:
- 为了重新评估电阻漂移在100nm以下的电气表现,Ge2Sb2Te5 (GST) PCM设备.
- 要区分散装和接口对阻力漂移的贡献.
- 确定负责GST PCM设备中电阻漂移的主要机制.
主要方法:
- 采用了测量技术的组合来研究电流传输和电阻漂移.
- 进行了稳定状态温度依赖测量,以分析电阻影响.
- 利用时间电流-电压 (I-V) 特性来观察漂移动态.
主要成果:
- 设备电阻主要受到电接触的影响,这表明接口占主导地位.
- 传导机制在接触处被确定为热电辐射 (Schottky).
- 阻力漂移直接与Schottky屏障高度的时间依赖的增加有关.
结论:
- 在 GST PCM 设备中阻力漂移的主要贡献者是 Schottky 屏障高度,用于在接口处注入孔.
- 接口效应,特别是在电气接触处,比散装效应发挥更重要的作用.
- 这凸显了在神经形态应用中优化接触接口对于稳定的PCM性能的重要性.
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