金属吸附和粘附能量在MgO上{100})
Charles T Campbell1, David E Starr
1Department of Chemistry, Box 351700, University of Washington, Seattle, Washington 98195-1700, USA. campbell@chem.washington.edu
Journal of the American Chemical Society
|August 1, 2002
概括
在MgO ((100) 上的金属吸附被用热量计研究. 吸附热与金属特性相关,揭示了对2D岛屿和3D电影的粘合和薄膜形成的见解.
科学领域:
- 表面科学是一门学科.
- 材料化学 材料化学
- 吸附现象是一种吸附现象.
背景情况:
- 了解金属-MgO (100) 相互作用对于薄膜生长至关重要.
- 之前对Cu,Ag和Pb的吸附热量在MgO{100}上进行了热量测量.
研究的目的:
- 将测量的吸附热量与散装金属属性相关联.
- 研究金属-MgO{100) 键能和粘附.
- 在二维 (2D) 和三维 (3D) 金属片中,阐明的粘合机制.
主要方法:
- 在MgO上测量Cu,Ag和Pb吸附热量的热量计100).
- 应用双向债券添加性模型来估计低覆盖债券能量.
- 与散装金属特性 (升华能,氧化物形成热量) 的相关性分析.
主要成果:
- 低覆盖范围的吸附热与初始粘附概率和岛密度相关,支持短暂移动前体模型.
- 在低覆盖范围的金属-MgO100) 键能与散装升华能相关,这表明在缺陷处具有主导性的共价金属-Mg键.
- 3D片的粘附能量与金属升华能量和大量氧化物形成热量相关,表明金属-氧和金属-Mg键的贡献.
结论:
- 在MgO100) 缺陷的覆盖率低的情况下,共价金属-Mg结合是显著的.
- 在3D金属薄膜中的界面粘合在MgO ((100) 上涉及金属-氧和共价金属-Mg 相互作用.
相关概念视频
Types of Chemical Bonds
Chemical bonding theories were pioneered by American chemist Gilbert N. Lewis. He developed a model called the Lewis model to explain the type and formation of different bonds. Chemical bonding is central to chemistry; it explains how atoms or ions bond together to form molecules. It explains why some bonds are strong and others are weak, or why one carbon bonds with two oxygens and not three; why water is H2O and not H4O.
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Bonding in Metals
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Metal-Ligand Bonds
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Metal-Semiconductor Junctions
The contact of metal and semiconductor can lead to the formation of a junction with either Schottky or Ohmic behavior.
Schottky Barriers
Schottky barriers arise when a metal with a work function (Φm) contacts a semiconductor with a different work function (Φs). Initially, electrons transfer until the Fermi levels of the metal and semiconductor align at equilibrium. For instance, if Φm > Φs, the semiconductor Fermi level is higher than the metal's before contact. The semiconductor's...
Schottky Barriers
Schottky barriers arise when a metal with a work function (Φm) contacts a semiconductor with a different work function (Φs). Initially, electrons transfer until the Fermi levels of the metal and semiconductor align at equilibrium. For instance, if Φm > Φs, the semiconductor Fermi level is higher than the metal's before contact. The semiconductor's...


