Synthesis of Ge1−xSnx Alloy Thin Films Using Ion Implantation and Pulsed Laser Melting (II-PLM)
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Ge1−xSnx thin films are interesting for all-group-IV optoelectronics because of a crossover to a direct bandgap with dilute Sn alloying. However, Sn has vanishing room-temperature equilibrium solubility in Ge, making their synthesis very challenging. Herein, we report on our attempts to synthesize Ge1−xSnx films on Ge (001) using ion implantation and pulsed laser melting (II-PLM). A maximum of 2 at.% Sn was incorporated with our experimental conditions in the samples as determined by Rutherford back scattering spectroscopy. A red-shift in the Ge optical phonon branch and increased absorption below the Ge bandgap with increasing Sn concentration indicate Sn-induced lattice- and band-structure changes after II-PLM. However, ion-channeling and electron microscopy show that the films are not of sufficient epitaxial quality for use in devices.
KeywordsGe1−xSnx alloy pulsed laser melting (PLM) ion implantation
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- 1.Y. Huo (PhD thesis, Stanford University, 2010).Google Scholar
- 7.V.R. D’Costa, Y. Fang, J. Mathews, R. Roucka, J. Tolle, J. Menendez, and J. Kouvetakis, Semicond. Sci. Technol. 24, 115006 (8 pp) (2009).Google Scholar
- 8.W. Smith and J. Hashemi, Foundations of Materials Science and Engineering, 4th ed. (New York: McGraw-Hill, 2006).Google Scholar
- 20.J.W. Mayer, Electron Devices Meeting, 1973 International (1973), pp. 3–5.Google Scholar
- 21.M. Nastasi and J.W. Mayer, Ion Implantation and Synthesis of Materials., 1st ed. (Springer Series in Materials Science, 2006), pp. 63–75.Google Scholar
- 22.M.A. Scarpulla (PhD thesis, University of California, Berkeley, 2006).Google Scholar
- 23.R.F. Wood, C.W. White, and R.T. Young, Pulsed Laser Processing of Semiconductors (Orlando, FL: Academic, 1984).Google Scholar
- 28.J. Ziegler, SRIM: The Stopping Range of Ions in Matter [Software]. www.srim.org. Accessed 15 Dec 2009.
- 30.T.L. Alford, L.C. Feldman, and J.W. Mayer, Fundamentals of Nanoscale Film Analysis., 1st ed. (Springer Series, 2007), pp. 84–103.Google Scholar