Characterization of the initial growth stages of electroless Ag(W) films deposited on Si(100)

Scanning tunneling microscopy (STM), high resolution scanning electron microscopy, and transmission electron microscopy (TEM) have been used to study the film evolution at the initial stage of deposition and the structure of electrolessly deposited silver films that contain tungsten [Ag(W)] on single crystal silicon (100). We present the surface covering process at the initial stage of electroless deposition. The surface reconstruction in this case takes place at room temperature. The state and position of the tungsten was also investigated; TEM measurements indicate that NaWO3 is present in the film. STM images of the Ag(W) film growth show a spiral feature that may reveal a dominant electrochemical driving force during the crystal growth. The presence of well-resolved steps in the deposition process and its electrochemical nature were demonstrated by fast immersion chronovoltametry. This method was also applied to follow the changes in the surface energy, which were caused by the surface pretreatment processes and the deposition process itself. (C) 2001 The Electrochemical Society.