https://doi.org/10.1051/epjap/2012120141
Bi-composition and light effects on the conductivity of Sn-Sb-Bi-Se amorphous chalcogenide alloys
1
Graphene Research Institute, Sejong University, Seoul 143-747, South Korea
2
Semiconductors Laboratory, Department of Physics, Guru Nanak Dev University, Amritsar 143005, India
a e-mail: muneer.fiziks@gmail.com
Received:
13
April
2012
Revised:
10
June
2012
Accepted:
26
June
2012
Published online:
3
August
2012
Thermally evaporated thin films of Sn10Sb20 − xBixSe70 (0 ≤ x ≤ 4) chalcogenide system were subjected to X-ray diffraction studies to check the amorphous nature of all the films. The dark conductivity increases with the increase in Bi content and the calculated values of dc activation energy initially increase for smaller Bi concentration and then decrease sharply with further addition of Bi. The photocurrent in the beginning increases with time and then saturates to a constant value for all the samples. The decay portion of photocurrent has two components, fast one followed by slow decay. Photocurrent versus light intensity follows the power law Iph ∝ Fγ and the values of exponent are also discussed. Except for x = 4 composition the photosensitivity drops for all the samples as the percentage of Bi increases. The values of differential lifetime determined from the decay curves are also reported.
© EDP Sciences, 2012