Skip to main content Accessibility help
×
Home

Phase Separation of β-SN in Strained, Compositionally Metastable Ge1-xSnx Alloys

  • Joshua W. Kriesel (a1) and Susanne M. Lee (a2)

Abstract

Using rf sputtering and post-deposition annealing in a differential scanning calorimeter (DSC), we manufactured bulk (4000 nm) films of crystalline Ge0.83Sn0.17. This Sn concentration is much greater than the solid solubility limit of Sn in Ge (x ≤ 0.01). Continued annealing thermally induces Sn phase separation from the alloy, limiting the ultimate attainable grain size in the metastable crystals. We examine, here, the mechanisms and kinetics of the processes limiting the size of the Ge0.83Sn0.17 polycrystals. From a combination of DSC, electron microprobe, and x-ray diffraction (XRD) measurements, we propose phase transformation mechanisms corresponding to crystallization of amorphous Ge0.83Sn0.17, crystallization of an as-yet unidentified phase of Sn, and phase separation of Sn from the Ge1-xSnx crystals. We were unable to observe the unidentified phase of Sn in XRD, but the phase must be present in the material to account for the quantitative discrepancies (as much as 8 at.%) in Sn percentages determined from each of the DSC, XRD, and electron microprobe measurements. Our models for the various transformation kinetics were corroborated by the subsequent phase-separated Sn melting behavior observed in the DSC: two Sn melting endotherms, one of which was 20–100°C lower than the bulk melting temperature of Sn. This depressed temperature endotherm we speculate represents liquefaction of nanometer-sized (β–Sn clusters.

Copyright

References

Hide All
1 Oguz, S., Paul, W., Deutsch, T.F., Tsaur, B.-Y., Murphy, D.V., Appl. Phys. Lett. 43, 848 (1983).
2 Jenkins, D.W. and Dow, J.D., Phys. Rev. B 36, 7994 (1987).
3 Lee, S.M. and Barmak, K., Mat. Res. Soc. Symp. Proc. 321, (Pittsburgh, PA, 1994) pp. 313318.
4 Lee, S.M., J. Appl. Phys., 75, 1987 (1994).
5 Turnbull, D., Jang, J.S.C. and Koch, C.C., J. Mater. Res. 5, 1731 (1990).
6 Christian, J.W., The Theory of Transformations in Metals and Alloys, 2nd ed., (Pergammon, Oxford, 1975), p. 542.

Related content

Powered by UNSILO

Phase Separation of β-SN in Strained, Compositionally Metastable Ge1-xSnx Alloys

  • Joshua W. Kriesel (a1) and Susanne M. Lee (a2)

Metrics

Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed.