Analysis of epitaxial CdxHg1 − xTe layers using RBS, SIMS and EER

Abstract

AbstractA combination of the techniques of Rutherford backscattering spectrometry (RBS), secondary ion mass spectrometry (SIMS) and electrolyte electroreflectance (EER) have been used to profile through epitaxial layers and heterostrutures of CdxHg1 − xTe. The layers analysed by these techniques were grown either by photosensitized or thermal metal organic vapour phase epitaxy (MOVPE). The use of the EER technique, combined with electro‐chemical etching, for depth profiling of layers is described. Good agreement between RBS and EER measurements of x has been achieved with a resolution of ±0.010 for RBS and ±0.002 for EER. A depth resolution of better than 50 Å has been achieved by all three of the techniques. SIMS has been used to profile for trace impurities in layers grown using the interdiffused multilayer process (IMP). Assessment of layer crystal quality using ion channelling and EER broadening parameter measurements is discussed. The advantages and disadvantages of each of the analysis techniques are discussed and compared.