AVS 50th International Symposium
    Thin Films Thursday Sessions
       Session TF-ThA

Paper TF-ThA9
Growth of Epitaxial Two-dimensional Layers of Indium on Si(100) by Femtosecond Pulsed Laser Deposition

Thursday, November 6, 2003, 4:40 pm, Room 329

Session: In-Situ / Ex-Situ & Real-Time Monitoring
Presenter: M.A. Hafez, Old Dominion University
Authors: M.A. Hafez, Old Dominion University
M.S. Hegazy, Old Dominion University
H.E. Elsayed-Ali, Old Dominion University
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The growth of high quality epitaxial metal films on Si is of interest to device technology. Pulsed laser deposition (PLD) produces energetic species, which result in the increase of the sticking coefficients and adatom surface mobility enhancing epitaxial growth. Compared to longer laser pulses, femtosecond (fs) laser pulses significantly alter the processes associated with ablation. Epitaxial growth of thin films by fsPLD has been previously reported. Heteroepitaxial growth of indium on Si(100)-(2x1) substrates is performed under ultrahigh vacuum (base pressure low 10@super -9@ Torr) with a Ti:sapphire laser (130 fs) at wavelength of 800 nm. Reflection high-energy electron diffraction (RHEED) is used during the deposition to study the growth dynamics and the surface structure of the grown films. Morphology of the indium films is examined by ex-situ atomic force microscopy (AFM). At a substrate temperature of ~145 °C, indium was initially found to grow two-dimensionally, and then three-dimensional islands were formed. Epitaxial indium thin films are found to grow at a deposition temperature of ~400 °C, which have a 3x4 structure as observed from the RHEED pattern. The RHEED analyses and intensity oscillations show that indium films grow with two-dimensional layers and the AFM reveals two-dimensional nucleation islands. Growth modes and nucleation of indium films at different deposition conditions are discussed.