相关实验视频
Updated: Jun 10, 2026

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Developing High Performance GaP/Si Heterojunction Solar Cells
Published on: November 16, 2018
在Ge/Si岛增长期间,金字塔和圆顶之间的过渡状态
1IBM T. J. Watson Research Center, Post Office Box 218, Yorktown Heights, NY 10598, USA.
概括
在上生长期间,德国岛从金字塔过渡到圆顶. 这种由温度影响的形状变化通过中间状态发生,并且在冷却后是可逆的,支持异常粗模型.
科学领域:
- 材料科学 材料科学 材料科学
- 表面科学是一门学科.
- 纳米技术 纳米技术
背景情况:
- 在 (001) 表面上生长的- (GeSi) 岛屿表现出复杂的形状演变.
- 了解岛屿形态对于半导体设备制造和应变管理至关重要.
研究的目的:
- 调查GeSi岛屿在生长过程中从金字塔结构到圆顶结构的实时形状转变.
- 阐明中间形状和温度在这种转变中的作用.
主要方法:
- 在现场实时观察Si上的GeSi岛屿增长.
- 分析岛屿形态,包括面向演变,在生长期间和生长后的化.
- 形状转换和可逆性的温度依赖研究.
主要成果:
- 小的GeSi岛屿是金字塔形的,而较大的岛屿则采用圆顶形状.
- 过渡涉及不对称的中间形状,越来越多的高度倾斜的方面.
- 金字塔的增长后化会导致类似的形状变化,这种变化取决于温度,在冷却后是可逆的.
结论:
- 在GeSi岛屿中观察到的金字塔到圆顶形状的转变是由不同的中间状态介导的.
- 过渡的可逆性和温度依赖性支持岛屿增长的异常粗化模型.
- 这些发现为管理表面纳米结构形成的基本机制提供了洞察力.
相关概念视频
Thermal expansion and Thermal stress: Problem Solving
San Francisco's Golden Gate Bridge is exposed to temperatures ranging from -15 °C to 40 °C. At its coldest, the main span of the bridge is 1275 m long. Assuming that the bridge is made entirely of steel, what is the change in its length between these temperatures?
To solve the problem, first, identify the known and unknown quantities. The initial length (L) of the bridge is 1275 m, the coefficient of linear expansion (α) for steel is 12 x 10-6/°C, and the change in temperature (ΔT) is 55 °C.
To solve the problem, first, identify the known and unknown quantities. The initial length (L) of the bridge is 1275 m, the coefficient of linear expansion (α) for steel is 12 x 10-6/°C, and the change in temperature (ΔT) is 55 °C.
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