Premium
Evaluation of deep‐impurity governed photoelectrical properties in differently doped CdTe
Author(s) -
Kadys A.,
Sudzius M.,
Jarasiunas K.,
Fochuk P.,
Feychuk P.,
Hellin M. L.,
Verstraeten D.
Publication year - 2007
Publication title -
physica status solidi (b)
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.51
H-Index - 109
eISSN - 1521-3951
pISSN - 0370-1972
DOI - 10.1002/pssb.200675149
Subject(s) - doping , materials science , photorefractive effect , cadmium telluride photovoltaics , charge carrier , impurity , photoconductivity , electron mobility , optoelectronics , electric field , crystal (programming language) , band gap , hall effect , condensed matter physics , analytical chemistry (journal) , chemistry , electrical resistivity and conductivity , physics , organic chemistry , chromatography , quantum mechanics , computer science , programming language
Abstract We investigated nonequilibrium carrier generation, transport, and recombination processes in differently doped bulk CdTe crystals by the contactless nonlinear optical technique – the degenerate four‐wave mixing. Doping by Ge, Pb, Sb, Se, Si, or Sn was reached by Bridgman, whereas vanadium doped CdTe ingots were grown by the vertical Bridgman–Stockbarger method. Some crystals of CdTe:Sb as well as CdTe:Ge were cut from the different parts of ingots. At 1064 nm below bandgap excitation by light interference pattern and varying the grating period, we measured the space‐charge field dependent values of effective diffusion coefficient and determined a sign of the photogenerated carriers. In samples, doped with V, Sb, Si, or Ge, the experiments revealed that the majority carriers are electrons, while in Pb, Se, Sb, Ge, or Sn‐doped crystals – the holes. Strong feed‐back effect of the light‐created SC electric field to subnanosecond carrier dynamics was observed in the crystals doped with Ge, Pb, Sb, or Sn. Carrier lifetimes longer than 40 ns together with long living SC field component makes the Ge, Sb, or Sn doped crystals as very promising photorefractive media for real time holographic devices. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)