AES DEPTH PROFILING OF SEMICONDUCTING EPITAXIAL LAYERS WITH THICKNESSES IN THE NANOMETER RANGE USING AN ION-BEAM BEVELING TECHNIQUE

An ion beam technique has been developed that allows the preparation o f bevels from semiconducting heteroepitaxial structures with smooth su rfaces and very shallow angles between 0.1 degrees and 0.001 degrees, The bevels are used for AES depth profiling of heterostructures by the line ran technique, Comparison of measured and calculated line scans from (Al, Ga)As/GaAs and (Si, Ge)/Si test structures shows the contrib utions of the electron escape depth and the ion beam mixing to the dep th resolution, Application examples are given for semiconductor laser structures where the interesting heterostructures are buried under a t hick overlayer. For such structures, the depth profiling by a line sca n across the bevel needs much less analysis time than conventional spu tter depth profiling. (C) 1997 by John Wiley & Sons, Ltd.