Trapping center parameters of TlGaSe2 layered crystals

Thermally stimulated current measurements are carried out on as-grown TlGaSe2 layered single crystals in the temperature range of 90-220 K with various heating rates. Experimental evidence is found for the presence of two trapping centers with activation energy 98 and 130 meV. The retrapping process is negligible for these levels, as confirmed by good agreement between the experimental results and theoretical predictions of the model that assumes slow retrapping. The calculation yielded 2.3 x 10(-24) and 1.8 x 10(-24) cm(2) for the capture cross section and 1.4 x 10(14) and 3.8 x 10(14) cm(-3) for the concentration of the traps studied