Resumen

MELENDEZ-LIRA, M.. Characterization by photoreflectance of E ₀ ´ and E ₁ silicon-like critical points in ion implanted Si _1-y C _y thin films. Superf. vacío [online]. 2005, vol.18, n.3, pp.1-3. ISSN 1665-3521.

The dependence of E0´ and E1 critical points energies with carbon content in Si1-yCy thin films grown by ion implantation and crystallization have been obtained by room temperature photoreflectance spectroscopy. We present results from samples crystallized by solid phase epitaxy and laser annealing. We found that the E0´ values depend on the crystallization procedure. For solid phase epitaxy crystallization, E0´ initially increases up to 20 meV for y=0.003 then decreasing to values near that of silicon for y =0.014. While for laser annealing the E0´ values are always lower than that of silicon. E0´ shows a behavior far from that predicted by the virtual crystal approximation and deformation potential theories. E1 shows a continuous increase as function of the carbon content, this is reasonably well described using the aforementioned theories.

Palabras llave : Semiconductor alloys; Si_1-yC_y; Photoreflectance.