Nonstoichiometry and solubility of impurity in In-doped PbTe films on Si substrates

The chemical quantitative composition, phase constitution, and crystal structure of doped with In lead telluride films on Si (1 0 0) or SiO2/Si (1 0 0) substrates have been studied in this work. By EPMA and atomic absorption measurements, it has been found that the concentration of In atoms y(In) varied from 0.0011 to 0.045 in these deposited Pb1-yInyTe films. The results of EPMA, SEM, and X-ray diffraction (XRD) measurements show that formation of In solid solutions in lead telluride matrix revealed not only in PbTe-InTe cross-section, but in PbTe-ln(2)Te(3) pseudobinary system also. The results of XRD show that the lattice parameter a(PbTe) of PbTe< In >/Si and PbTe< In >/SiO2/Si heterostructures is described by nonmonotone function and does not obey the Vegard's law within concentration interval 0.0011 less than or equal to y(In) less than or equal to 0.045. (C) 2003 Published by Elsevier Ltd.