The determination of solubility limits of gallium impurity in PbTe films doped with Ga on Si substrates
|Alexander M. Samoylov 1, Sergey V. Belenko , Emma A. Dolgopolova , Alexander M. Khoviv , Mikhail K. Sharov 1|
1. Voronezh State University (VGU), Universitetskaya Sq., 1, Voronezh 394006, Russian Federation
The determination of solubility limits of gallium impurity in PbTe films doped with Ga on Si substrates,
A.M. Samoylov, S.V. Belenko, E.A. Dolgopolova, A.M. Khoviv, M.K. Sharov, Voronezh State University, Universitetskaya sq., 1, 394006 Voronezh, Russian Federation.
The thin films and single crystals of PbTe doped with Ga are the perspective materials for detecting IR-radiation in middle wave range. The IR-sensitivity of these materials is similar to Cd1-xHgxTe solid solutions but process of fabrication is much less demanding.
The main purposes of this study are to discuss the experimental results, which have been received during the examination of the chemical quantitative composition, phase composition, and the real crystal structure of PbTe<Ga>/Si and PbTe<Ga>/SiO2/Si heterostructures, and to evaluate the solubility of Ga atoms in lead telluride thin films at different temperatures.
In this work the method of fabrication of PbTe<Ga>/Si and PbTe<Ga>/SiO2/Si heterostructures offers the direct HWE one stage synthesis, in which the doping and the layer condensation process proceeds simultaneously. On the base of SEM observations, XRD, and EPMA results the boundary of gallium’s limited solubility region in lead telluride matrix has been drawn. From the point of view of Gibbs’s compositional triangle of Pb – Ga - Te ternary system, one can make a conclusion that the analysis of the PbTe – GaTe pseudobinary cross section only, as it have been done earlier, does not explain, in general, the process of gallium’s solubility in PbTe matrix. For the fundamental understanding the formation process of Ga solid solutions it is necessary to consider the PbTe – Ga2Te3 and PbTe – Ga2Te5 polythermic cross sections in this ternary system also.
Presentation: Oral at E-MRS Fall Meeting 2009, Symposium D, by Alexander M. Samoylov
See On-line Journal of E-MRS Fall Meeting 2009
Submitted: 2009-05-11 13:28 Revised: 2009-07-13 10:52