Determination of the deep-hole capture cross-section in a-Se via xerographic and interrupted-field time-of-flight techniques

Discrete defect levels in the amorphous selenium bandgap

“…However, these are not the only defect levels that have been reported in the a-Se bandgap. Xerographic dark discharge [3,4] and interrupted-field time-of-flight (TOF) measurements [5] have indicated the occurrence of deep hole traps with an integrated density of about 10 13 cm À3 , while the presence of deep electron traps could be deduced from the study of sequential electron and hole TOF signals [6]. A further shallow defect level situated about 0.3 eV below the conduction band edge was recently resolved through a comparison of calculated and measured transient photocurrents of electrons in stabilized a-Se [7].…”

The dependence of the modulation transfer function on the blocking layer thickness in amorphous selenium x‐ray detectors

“…The blocking layer has a deep hole lifetime ഛ0.5 s. This lifetime corresponds to an integrated deep trap concentration of ϳ10 15 cm −3 , following the trap controlled transport discussions in Ref. 39. Using p t =5ϫ 10 14 cm −3 , assuming that most injected holes are trapped, L = 200 m, and setting E 0 =2 V m −1 ͑the value of the field for the MTF measure-ments͒, a thickness of only ϳ2 m is required to fully extinguish the field at the del electrodes.…”

Xerographic spectroscopy of gap states in Se-rich amorphous semiconductors review

“…Eq. (1) has been found [8] to predict the actual μτ product remarkably well. The paper [9] identifies and critically examines the theoretical problems involved in the determination of μτ from xerographic measurements.…”