Artigo
Decay of photo-excited conductivity of Er-doped SnO2 thin films
Fecha
2007-04-01Registro en:
Journal of Materials Science. New York: Springer, v. 42, n. 7, p. 2216-2221, 2007.
0022-2461
10.1007/s10853-006-1320-0
WOS:000245125700002
7730719476451232
0000-0001-5762-6424
Autor
Universidade Estadual Paulista (Unesp)
Resumen
Er-doped SnO2 thin films, obtained by sol-gel-dip-coating technique, were submitted to excitation with the 4th harmonic of a Nd:YAG laser (266 nm), at low temperature, and a conductivity decay is observed when the illumination is removed. This decay is modeled by considering a thermally activated cross section of an Er-related trapping center. Besides, grain boundary scattering is considered as dominant for electronic mobility. X-ray diffraction data show a characteristic profile of nanoscopic crystallite material (grain average size approximate to 5 nm) in agreement with this model. Temperature dependent and concentration dependent decays are measured and the capture barrier is evaluated from the model, yielding 100 meV for SnO2:0.1% Er and 148 meV for SnO2:4% Er.