AVS 53rd International Symposium
    Electronic Materials and Processing Thursday Sessions
       Session EM2-ThA

Paper EM2-ThA8
Sub-1 nm Equivalent Oxide Thickness Zirconium Doped Hafnium Oxide High-k Gate Dielectrics

Thursday, November 16, 2006, 4:20 pm, Room 2003

Session: Electronic Properties of High-k Dielectrics, Ferroelectrics, and Their Interfaces
Presenter: J. Yan, Texas A&M University
Authors: J. Yan, Texas A&M University
C.-H. Lin, Texas A&M University
A. Birge, Texas A&M University
J. Lu, Texas A&M University
Y. Kuo, Texas A&M University
Correspondent: Click to Email
Implementation of high-k gate dielectrics for the continuous scale-down of MOSFETs requires the equivalent oxide thickness (EOT) be less than 1 nm.@footnote 1@ In order to achieve this kind of ultra-thin film with high dielectric quality, the gate dielectric deposition and post-deposition annealing (PDA) processes need to be carefuly studied. Previously, we reported that sub-2nm EOT Zr-doped HfO2 could be prepared by the reactive co-sputtering method.@footnote 2@ In this work, we report new results on preparing the ultra-thin, e.g., EOT as low as 0.89 nm, Zr-doped HfOx dielectric films by sputtering from a composite target. Effects of PDA conditions, such as temperature and gas atmosphere, on material and electrical properties were investigated. The interface layer formation mechanism, which is critical to the low EOT, low interface states density, and low charge trapping density, was studied. The resulting films have Dit E11 to E12 cm-2eV-1, hysteresis less than 4mV, and leakage current 4 orders of magnitude lower than that of SiO2. The interface and bulk film material properties were characterized with the angle-resolved x-ray photoelectron spectroscopy and AFM. @FootnoteText@ @footnote 1@ ITRS, SIA (2005).@footnote 2@ Y. Kuo, et al., ECS Proc. High Dielectric Constant Gate Stack III, in press (2005).