Ab initio Study of the Si Adsorption on Mo(110)

The formation of the high reflectance polycrystalline Mo/amorphous Si multilayer used in extreme UV lithography technology was investigated using density functional theory calculations based on the generalised gradient approximation to perform ab initio total energy calculations. It was shown that single Si atom adsorption strongly favoured the hollow sites of Mo(110), and that of the surface diffusion of Si occurred by hopping between neighbouring hollow sites, with an energy barrier of 0.64 eV. Four covalent Mo-Si bonds were formed per adsorbed Si atom. Based upon surface formation energy determinations, 1 ML Si/Mo(110)-p(1 x 1) was energetically favourable in a Si-rich environment, whilst a clean Mo(110) was the most stable structure in a Si-poor environment. 16 refs.