PR3-XAS IMPLANTED WITH PR( LUMINESCENCE IN GAAS AND ALXGA1)

Praseodymium (Pr) emissions were investigated for Pr-implanted GaAs an d AlxGa1-xAs as a function of Al mole fraction, sample temperature, an d anneal temperature using photoluminescence (PL) spectroscopy. Two gr oups of major PL peaks have been observed near 1.6 and 1.3 mu m, which can be attributed to the crystal-field-split spin-orbit level transit ions of F-3(3) --> H-3(4) and (1)G(4) --> H-3(5) of pr(3+) (4f(2)), re spectively. The PL intensity of Pr3+ varies dramatically with the Al m ole fraction in Pr-implanted AlxGa1-xAs. For GaAs, the PL peak intensi ty near 1.3 mu m is strong and the peak intensity near 1.6 mu m is wea k, whereas the PL peak intensity near 1.6 mu m is much stronger than t hat of 1.3 mu m for AlxGa1-xAs. Furthermore, Al0.15Ga0.85As shows part icularly strong luminescence peaks near 1.6 mu m. PL emissions of Pr w ere detected for sample temperatures as high as 100 K, and several hot lines were identified. The optimal anneal temperatures for the Pr-imp lanted GaAs and AlxGa1-xAs are between 725 and 775 degrees C. Dual imp lantations of Pr and Er into Al0.15Ga0.85As have also been made, but t he PL results showed that the emission intensities of both ions did no t increase compared to those of identically prepared singly implanted samples. Possible excitation processes are explored in light of these results.