Jg. Cederberg et al., Erbium-doped GaAs grown using the novel precursor tris(3,5-di-tert-butylpyrazolato)bis(4-tert-butylpyridine)erbium, J CRYST GR, 195(1-4), 1998, pp. 105-111
A new erbium precursor, tris(3,5-di-tert-butylpyrazolato)bis(4-tert-butylpy
ridine)erbium was used to dope GaAs. Some of the incorporated erbium forms
an optically active center identified as Er-2O. The optical line shape attr
ibuted to this Er-2O center is much sharper and more intense than in GaAs d
oped with erbium using cyclopentadienyl-based erbium sources. Co-doping GaA
s:Er with shallow donors results in a quenching of the erbium-related lumin
escence, while co-doping with shallow accepters results in no significant c
hange in the Er-based spectrum. Mechanisms for this observed luminescence-q
uenching behavior are presented. Deep level transient spectroscopy performe
d on silicon or selenium co-doped GaAs : Er showed the presence of several
electron traps in the upper half of the band gap. (C) 1998 Elsevier Science
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