通过使用伪化物替代剂对西兰的氨解来增强化的形成
Anil Kumar Tummanapelli1,2, Yingqian Chen1,2, Ming Wah Wong1,2
1Department of Chemistry, National University of Singapore, 3 Science Drive 3, 117543, Singapore. chmwmw@nus.edu.sg.
Physical chemistry chemical physics : PCCP
|January 19, 2024
概括
研究人员探索了化 (SiN) 薄膜沉积的替代前体. 伪化物替代剂,特别是来自16组的替代剂,在SiN加工中显示出作为传统光环的有效替代品的希望.
科学领域:
- 材料科学 材料科学 材料科学
- 计算化学计算化学
- 化学工程是化学工程的重要组成部分.
背景情况:
- 在化 (SiN) 薄膜加工中使用的传统光环面临反应性,污染性和基质选择性方面的挑战.
- 探索替代前体对于推进SiN薄膜沉积技术至关重要.
研究的目的:
- 为了计算选潜在的伪化物替代物在西兰化合物上作为常规 halosilanes 的替代品.
- 为了研究 halosilanes 的氨解机制,并确定影响反应障碍的因素.
- 评估伪化物适用于SiN薄膜加工的适用性,包括低温原子层沉积 (ALD).
主要方法:
- 使用M06-2X/6-311++G(3df,2p) 理论水平进行密度函数理论 (DFT) 计算.
- 分析边界分子轨道和电荷密度,以了解反应机制.
- 从14至16组的西兰替代物的系统选.
- 使用集群模型来模拟表面以实现现实的障碍预测.
主要成果:
- 研究了 halosilanes 的氨溶解机制,揭示了影响激活屏障的关键因素.
- 来自16组的伪化物替代剂,特别是那些具有电子提取组的替代剂,表现出低反应障碍.
- 使用集群模型的DFT计算准确预测了氨溶解障碍,验证了简化的方法.
- 16组伪化物被确定为传统光环的实际替代品.
结论:
- 伪化物替代剂,特别是具有电子吸收特征的16组替代剂,为SiN薄膜沉积提供了对光环的可行替代品.
- 这些发现支持开发改进的SiN加工,包括低温ALD技术.
- 计算选为材料科学中识别新型前体提供了一种有效的策略.
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