Research on electronic structure and optical characteristic of S-adsorbed 3C–SiC.

An insight into electronic structure and optical feature of S-adsorbed 3C–SiC (111) surface is carried out employing first-principles calculation. It is found that the T o and B position systems with adsorption energies of 3.880 and 3.895, respectively, are relatively stable compared to the T w and C systems. Impurity energy levels are present near Fermi level in C and T w position adsorption systems and the band-gap decreases obviously in the two systems. A raindrop-like electron cloud of S atom can be observed in T w adsorption system and the order of the chemical bond strength in the adsorption system is (B , T o ) > T w > C. The B and T o adsorption systems have good light permeability in the visible and infrared regions, while the C and T w adsorption systems are relatively suitable as dielectric materials and have high service life when they as devices in the ultraviolet region. [ABSTRACT FROM AUTHOR]