INTEC   05402
INSTITUTO DE DESARROLLO TECNOLOGICO PARA LA INDUSTRIA QUIMICA
Unidad Ejecutora - UE
artículos
Título:
Evaluation of the characteristic curves of a-Si:H based devices with the Simmons?Taylor approximation when the defect pool model is used
Autor/es:
MARCELO G. DE GREEF; FRANCISCO A. RUBINELLI
Revista:
PHYSICA STATUS SOLIDI B-BASIC RESEARCH
Editorial:
WILEY-V C H VERLAG GMBH
Referencias:
Lugar: Weinheim; Año: 2015 vol. 252 p. 170 - 180
ISSN:
0370-1972
Resumen:
The performance of a-Si:H devices is highly sensitive to the
density of gap states: tail states are distributed in two
exponentials and defect states are generated by dangling bonds
(DB). The density of DB in a-Si:H can be evaluated with the
defect pool model (DPM). Charge trapping and recombination
of electron?hole pairs through tail states are described by the
Shockley?Read?Hall (SRH) formalism while defect states
behave as amphoteric. Equations derived with the SRH
formalism can be simplified with the Simmons?Taylor?s
approximation (STA), especially with the ?0K? approximation
(0KSTA). Amphoteric-like defect states were approximated by
donor- and acceptor-like decoupled states (DSA). The accuracy
of STA was tested in a-Si:H based devices when the density of
DB is evaluated with the DPM for different illumination
conditions, voltages, temperatures, and some key electrical
parameters. Our code was modified to include both the STA and
the DSA. Our results indicate that the STA is very accurate
under illuminated conditions. Under dark conditions, the STA
is acceptable for forward voltages but overestimates the dark
current at reverse voltages. The 0KSTA can be used under
illuminated conditions for any applied voltage and under dark
conditions for forward voltages.