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The presence of contamination at the Pb/p-PbSe interface corresponding to a Schottky contact leads to the formation of an n-type inversion layer resulting in an ohmic behaviour. In this work, the PbSe oxidation kinetics by air exposure is studied using XPS and AES measurements. We found that an oxide layer is formed at the surface, containing PbO and SeO2 compounds. Secondly, the oxide layer dissolution in KOH-based solutions is investigated. A C- and O-decontaminated PbSe surface is obtained after a few minutes soaking in a bath containing ethylene glycol as solvent. Auger microanalysis demonstrates that the decontaminated surface is made of PbxSe with x

Heterostructures of IV–VI compounds, such as epitaxial films of PbSe grown on Si(111) via a CaF 2 layer, have been the object of increasing scientific interest in the last few years because of their detection properties. A monolithic integration of the I-R detection functions is possible on an Si conventional read-out electronics. The high mismatch and the difference of the thermal expansion coefficients between Si and PbSe require the use of a buffer layer of CaF 2 . The CaF 2 /Si(111) interface has been widely studied but PbSe/CaF 2 belongs to a group of interfaces which has been rarely studied. Annealing of the CaF 2 surface under Se flux in the range 200–600°C shows the incorporation of Se into the CaF 2 surface at a temperature higher than the growth temperature. The Se incorporation increases the stability of the CaF 2 surface, avoids its oxidation and creates nucleation sites for PbSe. The optimization of the subsequent buffer layer is a key problem in the growth process. On a Se-terminated CaF 2 surface, the first stage of the PbSe nucleation has been studied by AES, RHEED, XPS and AFM.