Multilayer adsorption of Li on Si(100)2 x 1 surfaces studied with metastable de-excitation spectroscopy and thermal desorption spectroscopy

The multilayer adsorption of Li on Ta foil and Li on Si(100)2 x 1 surfaces is discussed, based on the experimental data of thermal desorption spectroscopy and metastable de-excitation spectroscopy. Taking the former results of Ba adsorption on Si(100)2 x 1 into account, it can be understood that above about 1 ML of Li coverage, intermixing or silicide formation starts at room temperature. However, the outermost surface adsorbed by more than 3.3 ML is like pure Li. When this sample (with an adsorption of more than 3.3 ML of Li and with a surface like that of pure Li) is heated to 250 degrees C, its outermost surface is changed into silicide. (C) 1999 Elsevier Science B.V. All rights reserved.