Structure of the band tails in amorphous selenium

TY - JOUR

T1 - Structure of the band tails in amorphous selenium

AU - Benkhedir, M. L.

AU - Brinza, M.

AU - Adriaenssens, G. J.

AU - Main, C.

PY - 2008/5/28

Y1 - 2008/5/28

N2 - Transient photocurrent measurements on evaporated a-Se layers indicate the presence of two sets of discrete traps in the band tail region. The shallower traps, at E-V + 0.20 eV and E-C - 0.28 eV, are found to be electrically neutral, while the deeper ones at E-V + 0.38 eV and E-C - 0.53 eV are related to the charged negative-U centres of a-Se. The density of the discrete traps is of the same order of magnitude as the disorder-induced background density in the valence and conduction band tails, preventing the characterization of the a-Se tail-state densities by a simple functional form.

AB - Transient photocurrent measurements on evaporated a-Se layers indicate the presence of two sets of discrete traps in the band tail region. The shallower traps, at E-V + 0.20 eV and E-C - 0.28 eV, are found to be electrically neutral, while the deeper ones at E-V + 0.38 eV and E-C - 0.53 eV are related to the charged negative-U centres of a-Se. The density of the discrete traps is of the same order of magnitude as the disorder-induced background density in the valence and conduction band tails, preventing the characterization of the a-Se tail-state densities by a simple functional form.

U2 - 10.1088/0953-8984/20/21/215202

DO - 10.1088/0953-8984/20/21/215202

M3 - Article

SN - 0953-8984

VL - 20

SP - -

JO - Journal of Physics: Condensed Matter

JF - Journal of Physics: Condensed Matter

IS - 21

M1 - 215202

ER -