Superficies y Vacío
Preparación del Manuscrito
Simulation of dispersive transient transport in amorphous multilayers
R. Ramírez-Bon1 and A. Picos-Vega2
1Centro de Investigación y de Estudios Avanzados del IPN, Unidad Querétaro.
Apdo. Postal 1-798, 76001 Querétaro, Qro., México.
2Centro de Ciencias de la Materia Condensada, Universidad Nacional Autónoma de México,
Apdo. Postal 2681, 22800 Ensenada, B.C., México.

Using the Monte Carlo method we simulate the charge carrier transient transport in amorphous layers of multilayers structures. In particular we studied the effect of the time delay of carriers at interfaces on the shape of transient photocurrents. The characteristics of transient photocurrents in amorphous multilayers, as obtained by the Time of Flight technique, are simulated by random walks through cubic lattices and compared to experimental data from the literature. It was considered different mobility for the different layers in the structure and an energy mismatch at the interface between two consecutive layers. We compared our simulated results with experimental data measured on Se/Se1-xTex multilayers. The transient photocurrents measured in these multilayers show a double-peak shape, which remains as a general characteristic for these systems and is explained in terms of the existence of two mechanisms of transport that may occur at the same time. The origin of the double-peak shape adopted by the reported photocurrents is discussed and it is shown that each peak is directly related to the time delay of charge carriers at the layer-layer and contact-layer interfaces respectively. We concluded  the existence of two conduction mechanisms  involved in the transport of carriers through the multilayers. One mechanism is hopping through localized states of the disordered layers and the other could be thermal activation at interfaces or direct tunneling through barriers.

: In memoriam.

Información General
Formato del  Resumen
Información para Exhibidores