Growth and properties of CdTe:Bi-doped crystals

Autor: Edgardo Saucedo, Omar S. Martinez, Osvaldo Vigil-Galán, I. Benito, Carmen M. Ruiz, Ernesto Diéguez, L. Fornaro, N.V. Sochinskii
Rok vydání: 2006
Předmět:
Zdroj: Journal of Crystal Growth. 291:416-423
ISSN: 0022-0248
Popis: CdTe:Bi crystals were grown by the vertical Bridgman method, varying the nominal Bi-dopant concentration in the range of 1×10 17 –1×10 19 at/cm 3 . Bi and Bi 1.8−2.3 Te precipitates are the most characteristic structural defects in these crystals. Raman spectroscopy studies have shown that Bi traps Te from the CdTe host lattice. Low-temperature photoluminescence in the 1.2–1.6 eV energy region is presented. Several new emissions related to the incorporation of Bi are observed. Semi-insulating CdTe was obtained ( ρ =2×10 10 Ω cm) for dopant concentration of the order of 1×10 17 at/cm 3 . The resisitivity decreased to values as lower as 1×10 5 Ω cm for higher concentrations. Photosensitivity studies show an evolution from typical conductivity to shallow acceptor defects-related conduction when the Bi concentration is increased.
Databáze: OpenAIRE