Luminescence of lanthanides and actinides implanted into binary III-V semiconductors and AlGaAs

Through luminescence experiments it was observed that lanthanides, or rare earths, and also actinides, may be successfully introduced into binary and ternary III-V Group semiconductors. The study supports the feasibility of producing infrared light emitting diodes (LEDs) for the 0.9 to 1.7 μm spectral range. Besides systematic spectral characterization through photoluminescence, excitation mechanisms and decay kinetics were also investigated. Ytterbium (Yb), erbium (Er), thulium (Tm), praseodymium (Pr), and uranium (U) were successfully implanted into GaAs, InP, GaP, AlAs or AlGaAs observed through photoluminescence and also verified by secondary ion mass spectrometry (SIMS). The impurities were implanted through high (1 MeV), intermediate (380, 390 keV), and low (140 keV) energy standard and nonstandard implantation methods, followed by post-implantation annealing using both rapid thermal and conventional furnace annealing. Details on the implantation techniques are given and implantation statistics were determined. The resulting characteristic sharp 4f- or 5f- emissions were seen around 1.0 μm for Yb3+ in InP, GaP, and AlGaAs; 1.5 μm for Er3+ in GaAs, InP, GaP, AlAs, and AlGaAs of four different Al mole fractions; 1.2 μm for Tm3+ in GaAs and InP; 1.1, 1.3, and 1.6 μm for Pr3+ in GaAs and InP; and from 1.6 to 1.7 μm for uranium in GaAs and InP. Preliminary evidence shows Ho-specific emissions in GaAs at 0.94 and 1.18 μm. Tm3+ emissions are assigned to transitions between the crystal-field-split spin-orbit levels 3H5 - 3H6 while for Pr3+, between the levels 1G4 - 3H4, 1G4 - 3H5, and 3 F3 - 3H4, respectively