Depth profiling of GaAsN/GaAs multiple quantum well structures has been performed by SIMS. It is shown that the experimental depth resolution does not depend on the kind of primary ions and improves proportionally with a decrease of the primary ion energy. The SIMS results are compared with data of x-ray analysis of nitrogen concentration in GaAsN layers and with transmission electron microscopy analysis of the thickness of the layers. Taking into account the mechanism of GaAsN layer formation, experimental SIMS depth profiles of nitrogen are interpreted as resulting from a superposition of ultrathin GaAsN layers of thickness approximately 2.5 nm and diffusion profiles of `excess' nitrogen formed during nitridation.
|Number of pages
|Surface and Interface Analysis
|Published - 2000