Evaluation of photoelectrical properties of Bi doped CdTe crystals
Idioma
en
Article de revue
Este ítem está publicado en
Journal of Materials Science: Materials in Electronics. 2008, vol. 19, n° Supplement 1, p. 234-238
Springer Verlag
Resumen en inglés
Nonequilibrium carrier generation, transport, and recombination features have been investigated in Bi-doped and Yb-codoped bulk CdTe crystals, using time-resolved picosecond free-carrier and photorefractive grating techniques. ...Leer más >
Nonequilibrium carrier generation, transport, and recombination features have been investigated in Bi-doped and Yb-codoped bulk CdTe crystals, using time-resolved picosecond free-carrier and photorefractive grating techniques. Peculiarities of deep-impurity dependent carrier generation were studied at below band-gap photoexcitation using 1064 nm wavelength. Carrier transport in light created space charge field provided the instantaneous diffusion coefficient values, dependent on excitation energy, and revealed a sign of the dominant photoexcited carriers in the crystals. The studies provided also a deeper insight into an initial occupation of deep impurity levels, which was found strongly dependent on doping and co-doping. At low Bi density (<i>∼</i>2 × 10<sup>17</sup> cm<sup>−3</sup>), the hole generation was dominant, while at higher doping (8 × 10<sup>17</sup> cm<sup>−3</sup>) the bipolar plasma generation prevailed. Codoping by Yb (∼5 × 10<sup>17</sup> cm<sup>−3</sup>) revealed deep donor features of deep defects and formation of a strong space charge field. Carrier dynamics in the given crystals was compared with CdTe:V ones, where vanadium is known to form the mid-gap donor levels.< Leer menos
Palabras clave en inglés
Crystals
Photoelectric properties
CdTe
Orígen
Importado de HalCentros de investigación