Application of the high-pressure thermoelectric technique for characterization of semiconductor microsamples: PbX-based compounds

Abstract

In this paper the technique of thermoelectric measurements at high pressure was applied for characterization of semiconductor microsamples based on lead chalcogenide compounds (p-PbSe, n-Pb 1−x Sn x Se). The Raman scattering technique at ambient pressure was used as an alternative tool for testing of the samples. Raman measurements have revealed broad peaks at 135 and 265 cm −1 for PbSe and Pb 1−x Sn x Se. Analogous spectra were obtained for PbS, and PbTe-based ternary compounds at higher and lower frequencies, respectively. The peaks have been attributed to the first-and second-order Raman modes. From resistivity and thermoelectric power data the linear decrease in the pressure of the NaCl → GeS structural phase transition with increasing Sn content has been established and the thermopower of high-pressure GeS phases have been determined. Thermoelectric properties of the samples at high pressure have shown high sensitivity to a small variation in the composition of the ternary Pb 1−x Sn x Se compounds, which makes it possible to distinguish semiconductor microsamples whose compositions are very similar.

Pressure-Induced Phase Transition in Pb1-xSnxSe Studied by Raman Spectra

“…Sn dopant was reported to decrease the transition pressure from 4.5 to 3 GPa. 10,20) Our high-pressure x-ray diffraction study of Pb 0.875 Sn 0.125 Se could assign the orthorhombic phase neither to GeS type nor to the Pnma; 21) nevertheless, the GeS type 3,4) was used for symmetry analysis of the Raman spectra.…”

“…A fresh chip of Pb 0.875 Sn 0.125 Se single crystal 10) of ~50 200 200 m 3 size was placed in a hole drilled into a metal gasket of a diamond window cell. KCl was used as a pressure-transmitting medium in order to both enhance the useful signal and reduce the background luminescence.…”

“…The electron structure of PbSe changes in a complicated manner under pressure, alternating gap and gapless states, and inversions of conduction and valence bands. 2,10,20,24,25) One of the possible reasons of this anomalous behavior of ( ) may arise from the electron-induced effects due to the changes in the electron band structure during decompression.…”

“…However, at the NaCl phases of all PbX, the forbidden first-order spectra preceding surface oxidation were still established under the variation of the laser line or the increase in laser power. [9][10][11][12][13][14][15][16][17][18][19] In the present work, we investigated the above phase transition in Pb 1-x Sn x Se (x=0.125) by Raman spectroscopy under a pressure of up to 6 GPa. Sn dopant was reported to decrease the transition pressure from 4.5 to 3 GPa.…”

High-Pressure Treatment up to 25~GPa of Czochralski Grown Si Samples Containing Different Admixtures and Defects

“…In the present work results of high-pressure thermo- [16,17]. A thermal dierence was produced by heating of the anvils.…”