Nanoscale surface clustering on CdTe epilayers
Résumé
We have studied the surface morphology of two dimensional CdTe films grown by atomic layer epitaxy on CdZnTe buffers. Atomic force microscopy observations in air show a strong evolution of the surface after the growth by forming clusters of around 20 nm in diameter and 3 nm in height. The size increase of these clusters as time proceeds is directly related to the formation of tellurium and cadmium oxides on the surface as revealed by x-ray photoelectron spectroscopy data. This nanoscale clustering then occurs ex situ, due to exposure to atmosphere which induces an oxidation of the CdTe epilayers.