Growth of epitaxial Yb silicide on Si(100) studied by metastable atom deexcitation spectroscopy and photemission

Films of different Yb thickness are deposited on Si(100) 2x1 and are annealed at increasing high temperature. The evolution of the valence-band electronic properties is followed with metastable deexcitation spectroscopy and photoemission. Different surface-structure phases are observed at progressively high annealing temperature. A 3x1 ordered phase is observed by low-energy electron diffraction (LEED) after annealing of the films at about 640 degreesC and it is associated to the formation of a stable silicide. Correspondingly, electronic states assigned to the Yb 6s-5d hybridized band and to Si 3s and 3p bands in the compound are observed. A further increase of the annealing temperature causes the system to evolve rapidly. At T>650 degreesC the LEED pattern shows a 3x2 periodicity. Above 700 degreesC, the films present a character similar to that of the Si substrate.

Films of different Yb thickness are deposited on (formula presented) and are annealed at increasing high temperature. The evolution of the valence-band electronic properties is followed with metastable deexcitation spectroscopy and photoemission. Different surface-structure phases are observed at progressively high annealing temperature. A (formula presented) ordered phase is observed by low-energy electron diffraction (LEED) after annealing of the films at about 640 °C and it is associated to the formation of a stable silicide. Correspondingly, electronic states assigned to the Yb (formula presented) hybridized band and to Si (formula presented) and (formula presented) bands in the compound are observed. A further increase of the annealing temperature causes the system to evolve rapidly. At (formula presented) the LEED pattern shows a (formula presented) periodicity. Above 700 °C, the films present a character similar to that of the Si substrate. © 2002 The American Physical Society.