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氢在GaAs和InP表面上的吸附可以用高分辨率电子能量损失谱(HREELS)来探测。Ga—H,As—H,In—H和P—H键的伸缩振动各自对应于不同的能量损失。但是As—H振动极容易和Ga—H振动追加声子损失相混淆,只有从损失峰的相对强度比较上来区别。实验得到吸附的氢与表面原子的成键情况取决于表面的原子结构及电子分布。对于GaAs(111)面,低暴露量时只形成Ga—H键,而高暴露量时还可以形成As—H键。而InP(111)表面由于是经过磷气氛退火处理的,在低暴露量下In—H与P—H键均可形成。InP(Ⅲ)面上只看到P—H损失峰,说明这个表面是完全以P原子结尾的。在(Ⅲ)面上出现小面的情形,则表面Ⅲ族和Ⅴ族原子均可同氢成键。
Hydrogen adsorption on the GaAs and InP surfaces can be detected using high-resolution electron energy loss spectroscopy (HREELS). The stretching vibrations of Ga-H, As-H, In-H and P-H bonds each correspond to a different energy loss. However, the As-H vibration is easily confused with the additional phonon loss due to the Ga-H vibration, and only the difference in the relative intensity of the loss peak is observed. The bond between the adsorbed hydrogen and the surface atoms experimentally depends on the atomic structure and electron distribution of the surface. For the GaAs (111) surface, only Ga-H bonds are formed at low exposures and As-H bonds at high exposures. On the other hand, InP (111) surface is annealed by phosphorus atmosphere and both In-H and P-H bonds can be formed at low exposure. Only the P-H loss peak is seen on the InP (III) plane, indicating that this surface is completely terminated by the P atom. In the case of a facet on the (III) plane, both the III and V atoms on the surface can bond with hydrogen.