the process, especially of the initial stage of the deposition. In this paper the first results obtained from in situ reflective highenergy electron diffraction (RHEED) measurements during the ALD of $Al_2O_3$ on Si(001), using $Al(CH_3)_3$ and $H_2O$ as precursors, are presented. The goal of this work is to show the feasibility of using a surface-sensitive analysis technique to study the surface chemistry during ALD. The results show the expected decrease in reflected intensity on deposition of aluminum atoms and a recovery of intensity, attributed to removal of methyl groups from the surface, on exposure to $H_2O$. Growth initiation by TMA exposure, and subsequent growth inhibition are observed. A discrete time model of ALD is used to analyze the measured decay in reflected intensity.
- SC-ICF: Integrated Circuit Fabrication