IUVSTA 15th International Vacuum Congress (IVC-15), AVS 48th International Symposium (AVS-48), 11th International Conference on Solid Surfaces (ICSS-11)
    Semiconductors Friday Sessions
       Session SC+SS-FrM

Paper SC+SS-FrM8
Thermal Growth of High-density Silicon Quantum Dots on SiO@sub 2@/Si(001) with Submonolayer Silicon Adatom Predeposition

Friday, November 2, 2001, 10:40 am, Room 111

Session: Growth and Epitaxy of Semiconductors
Presenter: J.G. Ekerdt, University of Texas at Austin
Authors: J.G. Ekerdt, University of Texas at Austin
J.H. Zhu, University of Texas at Austin
W.T. Leach, University of Texas at Austin
Correspondent: Click to Email
A nonthermal method to facilitate nucleation and subsequent thermal chemical vapor deposition of Si quantum dots on SiO@sub 2@/Si(100) with high density and uniform size is demonstrated. Submonolayers (0.12 to 0.02 ML) of Si adatoms are predeposited on a room temperature to 825 K SiO@sub 2@/Si(001) substrate by cracking disilane on a high-temperature filament in a UHV chamber at pressures on the order of 10@super -7@ Torr. The quantum dots are grown at 825 K with a disilane pressure of 2x10@super -6@super Torr. The Si quantum dot density is increased and size distribution is narrowed by predeposition of Si adatoms when compared to thermal growth on bare SiO@sub 2@/Si(100). The dot density and size is controlled by the amount of Si adatom predeposition; 9.5x10@super 11@ cm@super -2@ density and 5.5 nm size are demonstrated on SiO@sub 2@/Si(001). A surface kinetic model is also presented that accounts for dot nucleation, adatom formation during growth, diffusion of adatoms to growing dots and epitaxial growth of dots. The method provides an effective way to control the nucleation, and consequently the growth, of quantum dots on dielectric surfaces.