导电电子的分布,如在化的MAS NMR中表现的导电电子分布
James P Yesinowski1, Andrew P Purdy, Huaqiang Wu
1Chemistry Division, Naval Research Laboratory, Washington, DC 20375, USA. yesinowski@nrl.navy.mil
Journal of the American Chemical Society
|April 13, 2006
概括
核磁共振 (MAS NMR) 量化了半导体中的电子载体度. 这种方法揭示了化 (GaN) 由于添加剂的组成异质性,即使在低水平.
科学领域:
- 固态化学 固态化学
- 材料科学 材料科学 材料科学
- 核磁共振光谱学 核磁共振光谱学
背景情况:
- 半导体的特性是由电子载体度决定的.
- 描述剂诱导的电子分布对于材料性能至关重要.
- 现有的方法在量化这些影响时可能缺乏精度.
研究的目的:
- 开发一种定量方法来描述半导体中的电子载体度分布.
- 用NMR研究故意和非故意的兴奋剂对化 (GaN) 的影响.
- 建立NMR光谱特征与电子度异质性之间的联系.
主要方法:
- 使用神奇角旋转 (MAS) 核磁共振 (NMR) 光谱学.
- 分析化学合成的GaN样本的71Ga MAS NMR光谱.
- 执行旋转格的放松时间测量作为光谱转移的函数.
- 使用骑士转移和线形状分析量化电子载体度.
主要成果:
- 观察到在未使用毒素的GaN中异质扩大吸收,归因于Knight从退化的导电电子转移.
- 在Ge-doped GaN (0.13%重量) 中证明了显著的光谱扩展和高频移位.
- 导出了电子载体度的定量概率密度函数,表明了显著的组成异质性.
结论:
- MAS NMR为识别和量化半导体中电子载体度效应提供了一个明确的策略.
- 这项研究强调了GaN中组成异质性的存在,受多分布的影响.
- 这种NMR方法为半导体表征和质量控制提供了一个强大的工具.
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