IUVSTA 15th International Vacuum Congress (IVC-15), AVS 48th International Symposium (AVS-48), 11th International Conference on Solid Surfaces (ICSS-11)
    Dielectrics Tuesday Sessions
       Session DI-TuM

Paper DI-TuM10
Interface Reactions of High-K Y@sub 2@O@sub 3@ and Gd@sub 2@O@sub 3@ Gate Oxides with Si

Tuesday, October 30, 2001, 11:20 am, Room 130

Session: High K Dielectrics II
Presenter: E. Garfunkel, Rutgers University
Authors: B.W. Busch, Agere Systems
W.H. Schulte, Rutgers University
R. Kwo, Agere Systems
M. Hong, Agere Systems
J.P. Mannaerts, Agere Systems
B.J. Sapjeta, Agere Systems
T. Gustafsson, Rutgers University
E. Garfunkel, Rutgers University
Correspondent: Click to Email
Ultrathin Y2O3 and Gd2O3 films were e-beam evaporated onto Si(100) and investigated by high-resolution medium energy ion scattering with and without in-situ Si capping layers. Si-capped metal oxide films were stoichiometric (M2O3), and their interface with the Si substrate was sharp. Uncapped films that were exposed to air, however, contained excess oxygen and showed a 6-8 @Ao@ thick interfacial layer. Other than limited intermixing between the capping Si and metal oxide layers during deposition, the oxides did not react with the initially-amorphous Si overlayer until ~800 °C. Uncapped films showed additional Si uptake from the substrate at ~700 °C, while the capped films did not react with the substrate until ~900 °C. Results are discussed within the framework of the relevant solid-solid and solid-gas thermodynamics and kinetics. This work demonstrates the critical importance of gas ambient during growth and processing of high-K gate oxides.