Imaging and spectroscopy of individual atoms, clusters and interfaces in electronic materials and devices

Abstract. The smallest features on transistors used in integrated circuits today have approached atomic dimensions: the Si(h gate oxides are between 5 and 7 silicon atoms thick and the concentration of dopant atoms has increased to the point that electrically inactive dopant clusters as small as two atoms are common enough to affect device performance. We have used atomic-resolution STEM with single atom sensitivity to identify the size, structure and distribution of clusters responsible for the saturation of charge carriers and address the question of how many atoms are needed before the gate oxide loses its bulk properties.