摘要
目的研究Si(001)-(2×2×1):H表面的几何结构和电子特性.方法在周期边界条件下,采用基于密度泛函理论的广义梯度近似平面波超软赝势法,对Si(001)-(2×2×1):H表面结构进行了弛豫计算并对该表面进行电子结构分析.结果结果表明弛豫作用使得部分电子从第一层硅原子转移到了第二层硅原子上,从而导致表层硅呈现正电性.结论这样的电子结构特性将有助于负电性强的氧气分子在硅氢表面的吸附.弛豫后的Si(001)-(2×2×1):H表面的能带结构具有半导体材料的特征.
Objective To study the geometrical and electronic properties of the Si (001) - (2 × 2 × 1) : H surface. Methods Under the periodic boundary condition, the relaxation and electrnic structure of Si (001) - (2 ×2× 1) : H surface are studied by using ultrasoft pseudopotential method based on the densityfunctional theory (DFT). Results The results show that relaxation makes some electrons transferred from the first layer to the second layer, so the surface of the hydrogenated silicon carries with positive charge. Conclusion Such electronic structure properties are helpful for the adsorption of high electronegative oxygen molecules. And after relaxation, the band structure of Si (001) - (2 × 2 × 1) : H has the semiconductor properties.
出处
《河北北方学院学报(自然科学版)》
2008年第5期11-13,21,共4页
Journal of Hebei North University:Natural Science Edition
基金
河北北方学院科研资助项目(200706)