晶体Si能带的密度泛函及第一性原理计算

A Calculation of energy band of crystal silicon using density functional theory and first-principles

针对晶体Si在二极管、三极管、晶闸管和各种集成电路中的应用与其能带结构密切相关的问题,采用密度泛函理论及第一性原理的赝势平面波方法,从理论上计算了晶体Si的电子能带.计算结果表明:Si的晶格常数为0.540 nm,与实验参考值相吻合;其价带宽度为11.80 eV,导带宽度为9.58 eV,该结果与其他学者用OPW方法所计算的结果相符合;价带与导带之间的禁带宽度为0.80 eV,进一步说明了Si是良好的半导体材料.

Aimed at the close relationship between the applications of crystal silicon （Si） in diode, audion, thyristor and various integrated circuits, the electronic energy band of Si was calculated using density functional theory （DFT） and first-principles pseudopotential plane-wave method. The calculated results show that the lattice constant of Si is 0. 540 nm, which matches the experimental value. The valence band width is 11.80 eV and the conduction band width is 9.58 eV, which are consistent with the values calculated by the OPW method. The energy-gap width Eg between valence and conduction bands is 0. 80 eV. It further suggests that Si is a kind of good semiconductor material. The present results provide a useful theoretical reference for the study in the physical properties of crystal silicon.