AVS 53rd International Symposium
    Electronic Materials and Processing Thursday Sessions
       Session EM+AS-ThM

Paper EM+AS-ThM8
Trends in Core Level Binding Energies of Mixed Oxide Candidates for High-@kappa@ Dielectrics

Thursday, November 16, 2006, 10:20 am, Room 2003

Session: High-k Dielectric Characterization
Presenter: A. Mathew, University of Delaware
Authors: A. Mathew, University of Delaware
L. Bao, Dupont Inc.
K. Demirkan, University of Delaware
C.-G. Wang, ASM America Inc.
G.D. Wilk, ASM America Inc.
R.L. Opila, University of Delaware
Correspondent: Click to Email
Hafnium silicates and lanthanum aluminates are among the many proposed candidate materials for replacing the SiO@sub 2@ gate dielectric in transistors for low standby power applications. Photoelectron spectroscopy with its sensitivity to local chemical bonding is an invaluable tool for investigating these interfaces. Hafnium silicates were deposited using Atomic Layer Chemical Vapor Deposition (ALCVD@super TM@), and the lanthanum aluminates were sputter deposited. Systematic trends in core level binding energies are observed for the unannealed mixed oxide systems as a function of composition. The degree to which such shifts occur is seen to be a function of both the amount of charge transfer between the component cations as well as the local lattice potential, both initial state effects. The O 1s photoemission peak and the N 1s peak (in the case of nitrided films) reflects the local bonding environment in the film, and its variations with different concentrations of a number of cations are studied as well. The O 1s and N 1s peaks can be deconvoluted into components arising from its bonding with a higher or lower electronegativity cation, and their relative intensities vary with composition. These insights into the local bonding structure are important for improving our capability to engineer the ideal semiconductor / high-@kappa@ interface for optimal device performance.