Precursor state of oxygen molecules on the Si(001) surface during the initial room-temperature adsorption

초록

The initial adsorption of oxygen molecules on Si(001) is investigated at room temperature. The scanning tunneling microscopy images reveal a unique bright O-2-induced feature. The very initial sticking coefficient of O-2 below 0.04 Langmuir is measured to be similar to 0.16. Upon thermal annealing at 250-600 A degrees C, the bright O-2-induced feature is destroyed, and the Si(001) surface is covered with dark depressions that seem to be oxidized structures with -Si-O-Si- bonds. This suggests that the observed bright O-2-induced feature is an intermediate precursor state that may be either a silanone species or a molecular adsorption structure.

키워드