Resisistivity and Hall measurements were performed at temperatures from 10 to 320K on Bi-doped PbTe layers grown on (111) is suggested for n + PbTe contact layers in device application.

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A series of PbTe/PbEuTe double barrier samples with different barrier widths were successfully grown on BaF 2 substrates by molecular beam epitaxy. The electron concentration of PbTe spacer and well layers was controlled by the deviation from stoichiometry, while the buffer and cap layers were intentionally doped with bismuth to obtain low-resistivity layers to be used as top and bottom contacts. Assuming 50% of band offset, a barrier height of 150 meV was determined by infrared transmission measurements, corresponding to a PbEuTe barrier with 5% of europium content. The structural parameters of the samples were accurately determined by combining the measurement in a high-resolution x-ray diffractometer in the triple-axis configuration with a simulation within the framework of dynamical theory of diffraction.

This work presents the micro-Raman (µR) analysis in SiGe nanoclusters formed by rapid thermal annealing (RTA). Heterostructure of a-Si:H/Ge/a-Si:H was grown on p-Si (001) substrate by Electron Cyclotron Resonance ECR plasma deposition and e-beam technique. Different parts of the sample were heated at 1000• C during 40, 50, 60 and 70 seconds. The samples as-deposited and RTA processed were characterized by Raman measurements in order to evaluate the Ge concentration and strain for different annealing times. The same parameters were extracted from high-resolution x-ray diffraction (HRXRD) performed in grazing incidence x-ray reflection mode (GIXRR). The µR spectra were sensitive to film strain changes due to the Ge diffusion during RTA process. The association of both characterization techniques provides information about some features of the SiGe nanoclusters at different annealing times. The results show the potential micro-Raman applicability for SiGe nanoclusters embedded in amorphous structure characterization.