TRANSFORMATION OF NATIVE DEFECTS IN BULK GAAS UNDER ULTRASONIC VIBRATION

The effect of high-intensity ultrasonic vibration on the spectrum of d eep electron traps in bulk n-type GaAs has been studied by means of de ep-level transient spectroscopy. The ultrasonic treatment results in a drastic reduction of the EL6 trap concentration and a generation of t hree other traps, suggesting an ultrasound-driven transformation of de fects associated with the traps. It is argued that the traps EL6, EL5 and EL18 are associated with the following native defects: As-Ga-V-As, V-Ga-V-As and V-Ga respectively. The defect transformations are descr ibed by two reactions involving emission of arsenic interstitials.