Helium atom scattering from the Si(111) surface at high temperatures
Helium atom scattering from the Si(111) surface at high temperatures
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DOI：
10.1103/physrevb.56.4642
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发表时间：
1997-08-15
影响因子：
3.7
通讯作者：
Greene, EF
中科院分区：
文献类型：
--
作者：
Lange, G;Meli, CA;Greene, EF
用氦原子散射研究了Si（111）表面在900 ~ 1600 K温度范围内的结构。即使在已知的（7 × 7）到“（1 × 1）”跃迁之下，吸附原子也变得移动的，并且，当达到1140 K附近的跃迁时，镜面和积分级衍射峰具有突然的强度变化，一些上升，另一些下降，而七级衍射峰消失。在过渡区之上，吸附原子仍然存在，在有序但松弛的表面外双层上快速移动，并由其支撑。第二次转型。首次由Ishizaka和同事报道的发生在1470 K附近。当温度接近熔点时，所有衍射峰的损失和镜面反射峰的衰减指示完全无序的表面。
Helium atom scattering has been used to investigate the structure of the Si(111) surface in the temperature range from 900 to 1600 K. Even below the well-known (7x7) to ''(1x1)'' transition the adatoms become mobile, and, when the transition is reached near 1140 K, the specular-and integral-order diffraction peaks have sudden intensity changes, some up and others down, while the seventh-order peaks disappear. Above the transition the adatoms remain, moving rapidly on, and supported by, the ordered but relaxed, outer bilayer of the surface. A second transition. first reported by Ishizaka and co-workers occurs near 1470 K. The loss of all diffraction peaks and the attenuation of the specular peak indicate a completely disordered surface as the temperature approaches the melting point.