Role of hydrogen adsorption on the carbon terminated β-SiC(100)-c(2 × 2) surface structure: a theoretical approach

The role of hydrogen adsorption on different clean surface models for the carbon terminated β-SiC(100)-c(2 × 2) surface structure is investigated through the use of ab initio calculations. The structural and electronic effect of hydrogen atoms bonded to carbon and/or silicon dimers is specifically considered and compared with the results for a clean surface model. The presence of adsorbed hydrogen atoms affects the atomic equilibrium positions, as well as electronic properties, of the atoms of the clean structure. These last properties are altered in different directions if the adsorption occurs in one or the other of the two investigated models. The changes in both structural and electronic properties were evaluated and compared with those of the clean surface. From our obtained results, a possible metallization, as a result of hydrogen adsorption, is theoretically postulated to occur in a similar way to what occurs with the silicon terminated β-SiC(100)(3 × 2) surface.