AVS 49th International Symposium
    Thin Films Thursday Sessions
       Session TF-ThA

Paper TF-ThA9
Ultra-thin Silicon- and Aluminum Oxides on Silicon formed Layer-by-layer

Thursday, November 7, 2002, 4:40 pm, Room C-101

Session: Ultra Thin Films
Presenter: P. Morgen, University of Southern Denmark (SDU)
Authors: P. Morgen, University of Southern Denmark (SDU)
T. Jensen, University of Southern Denmark (SDU)
C. Gundlach, University of Southern Denmark (SDU)
K. Pedersen, Aalborg University, Denmark
N. Skiversen, Aalborg University, Denmark
P. Kristiansen, Aalborg University, Denmark
S.V. Hoffman, Aarhus University, Denmark
Z.S. Li, Aarhus University, Denmark
Correspondent: Click to Email
At the end of the "road" for silicon based micro- and nano-electronics the gate oxide layers must shrink to their ultimate limits of thickness. We have developed some new layer-by-layer assembly procedures to form the thinnest possible oxides (0.3 - 5nm). These are then subjected to various types of measurements of their structure, chemical-, physical-, and electrical properties. We report details of the different processes to form these oxides, and their nano-chemical composition at - and vertically above - the interface, including a comparison of oxides grown on the Si (111) and Si (001) faces, in studies primarily using synchrotron-induced photoemission. We have established a procedure to monitor the field across ultra-thin layers of silicon oxide, with deposition of Ag on top of the oxide, ranging in coverage from dispersed atoms to above a full layer. Such a field exists for the Si (111)/silicon oxide interface but not for the Si (001)/silicon oxide interface after our processes. In both cases a Schottky barrier is formed under a thicker Ag layer, with the silicon oxide between the metal and semiconductor. Aluminum oxide has recently attracted a lot of interest as a substitute for silicon oxide on silicon, as it has a much higher dielectric strength than for a comparable thickness of silicon oxide. With our method, the layer-by-layer growth of aluminum oxide on silicon is very easy to control and to extend to other substrates than silicon.