深度石墨素捐赠者和电子定位在化中
1United States Naval Research Laboratory, Washington, DC, United States of America.
概括
硫,和作为化的深层,而不是浅层的捐赠者. 这种行为与DX中心不同,解释了实验中观察到的多邦激活能量.
科学领域:
- 材料科学 材料科学 材料科学
- 固态物理 固态物理
- 计算化学计算化学
背景情况:
- 化 (AlN) 是一种宽带半导体,在电子领域具有潜在的应用.
- 了解兴奋剂的行为对于控制AlN的电特性至关重要.
- 之前的研究已经探讨了各种兴奋剂,但AlN中的深度捐助国需要进一步调查.
研究的目的:
- 为了研究化 (AlN) 中的石化捐赠体 (S,Se,Te) 的电子特性.
- 为了确定这些素捐赠者是否表现为浅层或深层剂.
- 为了阐明实验观察到的激活能在杂的AlN的起源.
主要方法:
- 使用混合密度函数理论 (DFT) 的计算.
- 模拟了AlN中S,Se和Te的电子结构和电荷状态.
- 分析了与剂结合的电子极子的形成和稳定性.
主要成果:
- 在AlN中,素供体 (S,Se,Te) 形成深度供体状态,其水平在导电带边缘以下为0.45 eV或更高.
- 这种深度捐赠者的行为与其他兴奋剂中观察到的DX中心现象不同.
- 预计,当与这些石化剂和Si结合时,会形成转移稳定的小电子极子.
- 波拉龙形成的计算激活能量与实验观测结果 (0.20.3 eV) 相一致.
结论:
- 硫,和不是化中浅的捐赠者.
- 深度供体状态和相关的电子极子解释了实验观察到的 dopant 激活能量.
- 这些发现为基于AlN的电子设备的设计和制造提供了关键的见解.
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