ISSN:
1089-7550
Source:
AIP Digital Archive
Topics:
Physics
Notes:
We report a cross investigation of the effect of interdiffusion on the photoluminescence and Raman spectra of a single quantum well of InGaAs (80 A(ring) wide) sandwiched between two large InGaAsP barriers. First, we investigate the blue shift of the recombination line (2 K) after annealing at 650 and 750 °C from 15 min to 2 h. We assume one single diffusivity coefficient for all atomic species (i.e., conservation of the lattice matching after annealing) and deduce the amount of intermixing through a model calculation. We find average diffusivity coefficients D=9.5×10−3 A(ring)2 s−1 and D=2×10−1 A(ring)2 s−1 at 650 and 750 °C, respectively. This agrees well with previous measurements reported for the parent system InGaAs/InP and supports an activation energy EA=2.54 eV. Next we investigate, on the same series of samples, the change in phonon frequency associated with the GaAs longitudinal-optical-like mode in the active InGaAs layer. To connect quantitatively the change in wave number with the change in arsenic composition, versus annealing sequence, one must use a carefully checked calibration curve. We show that the linear relationship Δy/Δω=4×10−2(cm) provides a satisfactory agreement with the results of our photoluminescence investigation. This gives for the amount of arsenic leaving the well Δy≈−5% per h1/2 at 650 °C and −20% per h1/2 at 750 °C, respectively.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.352882
