AVS 47th International Symposium
    Plasma Science and Technology Friday Sessions
       Session PS-FrM

Paper PS-FrM4
Plasma Enhanced Chemical Vapor Deposition of Zirconium Oxide: Spectroscopic, Material and Device Characterizations

Friday, October 6, 2000, 9:20 am, Room 310

Session: Dielectrics II
Presenter: J.P. Chang, University of California, Los Angeles
Authors: J.P. Chang, University of California, Los Angeles
B. Cho, University of California, Los Angeles
D. Bae, University of California, Los Angeles
L. Sha, University of California, Los Angeles
Correspondent: Click to Email
As metal-oxide-semiconductor devices continue to shrink in dimensions, high dielectric constant materials such as zirconium oxide@footnote 1@ are needed in both transistor and capacitor structures for improved charge storage and reduced leakage current. In this work, zirconium t-butoxide (Zr(OC@sub 4@H@sub 9@)@sub 4@) is used with O@sub 2@ to deposit zirconium oxide on silicon in a high density Electron Cyclotron Resonance reactor. The gas phase reactions including the decomposition of precursors are investigated using optical emission spectroscopy (OES). Optical emission intensities from the atomic (Zr, C, O and Ar) and molecular species (ZrO, CH and CO) are recorded and quantified as a function of process parameters such as gas flow rates, process pressure, source power, and substrate temperature. Langmuir probe is used to determine the plasma potnetial, the electron density, n@sub e@, and electron temperature, T@sub e@. Various surface analysis techniques including X-ray photoelectron spectroscopy and X-ray diffraction are used to analyze the composition, chemical states, and crystalline structure of the deposited ZrO@sub 2@ films. These measurements are combined to propose realistic gas-phase and surface reaction mechanisms. The effect of in-situ post-deposition annealing on surface composition and film morphology is also investigated at 500-700°C in various ambient, including N@sub 2@, Ar, and O@sub 2@. NMOS transistors and MOS capacitors of a poly-Si(200nm)/ZrO@sub 2@/Si structure are fabricated and tested to determine the dielectric constant, leakage current, I-V and C-V characteristics of ZrO@sub 2@. Moreover, stress induced leakage current and time dependent dielectric breakdown are also investigated to determine the material reliability for the application of ZrO@sub 2@ in microelectronics. @FootnoteText@@footnote 1@ D. J. Hubbard and D. G. Schlom, "Thermodynamic stability of binary oxides in contact with silicon", Journal of Materials Research, 11(11), 2757(1996).