AVS 47th International Symposium
    Semiconductors Friday Sessions
       Session SC+EL-FrM

Paper SC+EL-FrM11
Growth and Characterization of Gadolinium Oxide Gate Dielectric on Gallium Nitride

Friday, October 6, 2000, 11:40 am, Room 306

Session: III-Nitride Processing and Devices
Presenter: B.P. Gila, University of Florida
Authors: B.P. Gila, University of Florida
K.N. Lee, University of Florida
K.K. Harris, University of Florida
W. Johnson, University of Florida
V. Krishnamoorthy, University of Florida
C.R. Abernathy, University of Florida
F. Ren, University of Florida
S.J. Pearton, University of Florida
Correspondent: Click to Email
Fabrication of high performance metal oxide semiconductor field effect transistors (MOSFETs) on gallium nitride will require both good interfacial electrical characteristics and good thermal stability. While dielectrics such as SiO@sub 2@ and GaGdO have demonstrated low to moderate interface state densities, questions remain about their thermal stability and reliability, particularly for use in high power or high temperature widebandgap devices. In this talk we will discuss the utility of gadolinium oxide, Gd@sub 2@O@sub 3@, as a gate dielectric material on GaN. Gadolinium oxide deposited by gas source molecular beam epitaxy from elemental Gd and an electron cyclotron resonance (ECR) oxygen plasma has been found to produce layers with excellent surface morphologies as evidenced by SEM and AFM, with a surface roughness of less than 1 nm. Surface preparation techniques, both in-situ and ex-situ, have been explored to produce films of different crystal morphologies as evidenced by RHEED and TEM. Stoichiometric films can be easily obtained over a range of growth temperatures, growth rates and oxygen flows. This talk will describe the relationship between deposition conditions and film characteristics for Gd@sub 2@O@sub 3@, and will present electrical characterization and thermal stability of capacitors fabricated from Gd@sub 2@O@sub 3@ on GaN.