First Principle Band Calculations of Mg₂Si Thin Films with (001) and (110) Orientations

We investigate the surface band structure in Mg2Si thin films using the first principle band structure calculations. When the film is stacked along the [001] direction, surface band structures appear inside quantum confinement band structures originates from the bulk band structure. When the film is stacked along the [110] direction, the semiconductor gap retains while a direct band gap appears.