Journals / Turkish Journal of Physics / 2006 / Cilt: 30 - Sayı: 3

Modulated Photoconductivity Studies of a-As2Se3 Thin Films

Pages
181–188
DOI
—

Abstract

Modulated photocurrent measurements in amorphous arsenic triselenide (a-As2Se3) is reported. Particular focus is paid towards photocarrier lifetimes as a function of temperature, and applied electric field (i.e. dc) were determined by using the quadrature frequency-resolved spectroscopy method. The activation energy from the photocurrent as a function of temperature was determined to be about 125 meV for a constant illumination intensity of 2.3 mW. Its value was found to be almost independent of the applied electric field. The exponent n in the power law relationship (Iph \propto Gv) between generating flux and photocurrent was obtained under different electric fields. The electric field dependence of photocurrent at various temperatures was also measured. A very little non-ohmic contact behavior was observed at low fields and at high temperatures.

Özet

Modulated photocurrent measurements in amorphous arsenic triselenide (a-As2Se3) is reported. Particular focus is paid towards photocarrier lifetimes as a function of temperature, and applied electric field (i.e. dc) were determined by using the quadrature frequency-resolved spectroscopy method. The activation energy from the photocurrent as a function of temperature was determined to be about 125 meV for a constant illumination intensity of 2.3 mW. Its value was found to be almost independent of the applied electric field. The exponent n in the power law relationship (Iph \propto Gv) between generating flux and photocurrent was obtained under different electric fields. The electric field dependence of photocurrent at various temperatures was also measured. A very little non-ohmic contact behavior was observed at low fields and at high temperatures.

Keywords: Amorphous As2Se3, Photoconduction, recombination, lifetime, trapping.