Cathodoluminescence study of plastically deformed GaAs

Infrared cathodoluminescence (IR–CL) micrographs were taken of surfaces perpendicular (11¯2) and parallel (021) to the bend axis 11¯2 of GaAs single crystals bent at 700 °C in four-point bending to introduce α-Ga and β-As dislocations. At the bend center, light and dark checkered patterns associated with dislocations could be observed only in the IR–CL micrographs but not by optical, infrared, or secondary electron emission microscopy. Dislocation densities to ρ ≈ 5 × 106 cm−2 could be determined nondestructively to within 20% of the theoretical values. No significant changes related to the type of dislocation or dislocation density were observed either in the peak half-width or peak position at E = 1.411 eV. However, decreases of 40–70% in the relative IR–CL intensity were observed in the bent samples with predominantly α or β dislocations.