过度和不足协调的原子作为无形化中电子和孔陷的来源 (a-Si3N4)
Christoph Wilhelmer1,2, Dominic Waldhoer2, Lukas Cvitkovich2
1Christian Doppler Laboratory for Single-Defect Spectroscopy in Semiconductor Devices, Institute for Microelectronics, TU Wien, 1040 Wien, Austria.
Nanomaterials (Basel, Switzerland)
|August 26, 2023
概括
新的研究确定了化薄膜中以前未知的电荷捕获点,这对于充电陷闪存 (CTF) 设备内存至关重要. 这些内在的电子陷解释了CTF设备中的内存效应.
科学领域:
- 材料科学 材料科学 材料科学
- 固态物理 固态物理
- 计算化学的计算化学
背景情况:
- 化 (Si3N4) 薄膜对于充电陷闪光灯 (CTF) 设备至关重要,作为充电存储层.
- 在Si3N4中负责记忆效应的电荷捕获点的确切性质仍然不清楚,尽管确定了Si悬挂键 (K中心).
- 现有的研究表明,Si悬挂键只占电活性缺陷的一小部分,需要探索替代的捕获地点.
研究的目的:
- 为了研究无形化的原子和电子结构.
- 在Si3N4膜中识别和描述新的电荷捕获点.
- 为了确定这些内在缺陷对CTF设备内存效应的贡献.
主要方法:
- 使用机器学习的力场和分子动力学模拟 (融化和灭) 来生成无形Si3N4模型结构.
- 使用密度函数理论与混合函数的结构性和电子性质的研究.
- 通过非辐射多声波模型分析捕获地点,计算放松能量和热力学电荷过渡水平.
主要成果:
- 在无形Si3N4中,电子和孔位于过度和不足协调的原子附近,在带间隙内产生缺陷状态.
- 在这些内在缺陷地点计算了电荷发射的高能障碍和电荷捕获的微不足道障碍.
- 这些内在的电子陷显著促进了在CTF设备中观察到的记忆效应.
结论:
- 无形Si3N4含有与协调缺陷相关的内在电子陷,这是CTF设备内存效应的关键.
- 这些发现为CTF技术中的电荷存储机制提供了更深入的理解.
- 这项研究通过控制缺陷属性,为优化基于Si3N4的内存设备打开了道路.
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