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Effect of deposition pressure on the microstructure and thermoelectric properties of epitaxial ScN(001) thin films sputtered onto MgO(001) substrates

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Abstract

Four epitaxial ScN(001) thin films were successfully deposited on MgO(001) substrates by dc reactive magnetron sputtering at 2, 5, 10, and 20 mTorr in an Ar/N2 ambient atmosphere at 650 °C. The microstructure of the resultant films was analyzed by x-ray diffraction, scanning electron microscopy, and transmission electron microscopy. Electrical resistivity, electron mobility and concentration were measured using the room temperature Hall technique, and temperature dependent in-plain measurements of the thermoelectric properties of the ScN thin films were performed. The surface morphology and film crystallinity significantly degrade with increasing deposition pressure. The ScN thin film deposited at 20 mTorr exhibits the presence of <221> oriented secondary grains resulting in decreased electric properties and a low thermoelectric power factor of 0.5 W/mK2 at 800 K. The ScN thin films grown at 5 and 10 mTorr are single crystalline, yielding the power factor of approximately 2.5 W/mK2 at 800 K. The deposition performed at 2 mTorr produces the highest quality ScN thin film with the electron mobility of 98 cm2 V−1 s−1 and the power factor of 3.3 W/mK2 at 800 K.

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References

  1. K.A. Gschneider, G.A. Melson, D.A. Melson, D.H. Youngblood, and H.H. Schock: Scandium: Its Occurrence (Academic Press, London, 1975), p. 165.

    Google Scholar 

  2. D. Gall, I. Petrov, L.D. Madsen, J-E. Sundgren, and J.E. Greene: Microstructure and electronic properties of the refractory semiconductor ScN grown on MgO(001) by ultra-high vacuum reactive magnetron sputter deposition. J. Vac. Sci. Technol., A 16, 2411 (1998).

    Article  CAS  Google Scholar 

  3. D. Gall, M. Stadele, K. Jarrendahl, I. Petrov, P. Desjardins, R.T. Haasch, T-Y. Lee, and J.E. Greene: Electronic structure of ScN determined using optical spectroscopy, photoemission, and ab initio calculations. Phys. Rev. B 63, 125119 (2001).

    Article  Google Scholar 

  4. D. Gall, I. Petrov, N. Hellgren, L. Hultman, J.E. Sundgren, and J.E. Greene: Growth of poly- and single-crystal ScN on MgO(001): Role of low-energy N2+ irradiation in determining texture, microstructure evolution, and mechanical properties. J. Appl. Phys. 84, 6034 (1998).

    Article  CAS  Google Scholar 

  5. B. Saha, J. Acharya, T.D. Sands, and U.V. Waghmare: Electronic structure, phonons, and thermal properties of ScN, ZrN, and HfN: A first-principles study. J. Appl. Phys. 107, 033715 (2010).

    Article  Google Scholar 

  6. M.A. Moram, Z.H. Barber, and C.J. Humphreys: The effect of oxygen incorporation in sputtered scandium nitride films. Thin Solid Films 516, 8569 (2008).

    Article  CAS  Google Scholar 

  7. J.P. Dismukes, W.M. Yim, and V.S. Ban: Epitaxial growth and properties of semiconducting ScN. J. Cryst. Growth 13, 365 (1972).

    Article  Google Scholar 

  8. J.M. Gregoire, S.D. Kirby, G.E. Scopelianos, F.H. Lee, and R.B. van Dover: High mobility single crystalline ScN and single-orientation epitaxial YN on sapphire via magnetron sputtering. J. Appl. Phys. 104, 074913 (2008).

    Article  Google Scholar 

  9. J.M. Gregoire, S.D. Kirby, M.E. Turk, and R.B. van Dover: Structural, electronic and optical properties of (Sc, Y) N solid solutions. Thin Solid Films 517, 1607 (2009).

    Article  CAS  Google Scholar 

  10. P.V. Burmistrova, J. Maassen, T. Favaloro, B. Saha, S. Salamat, Y.R. Koh, K.S. Lundstrom, A. Shakouri, and T.D. Sands: Thermoelectric properties of epitaxial ScN films deposited by reactive magnetron sputtering onto MgO(100) substrates. J. Appl. Phys. 113, 153704 (2013).

    Article  Google Scholar 

  11. S. Kerdsongpanya, N. van Nong, N. Pryds, A. Zukauskaite, J. Jensen, J. Birch, J. Lu, L. Hultman, G. Wingqvist, and P. Eklund: Anomalously high thermoelectric power factor in epitaxial ScN thin films. Appl. Phys. Lett. 99, 232113 (2011).

    Article  Google Scholar 

  12. M.A. Moram, S.V. Novikov, A.J. Kent, C. Nörenberg, C.T. Foxon, and C.J. Humphreys: Growth of epitaxial thin films of scandium nitride on 100-oriented silicon. J. Cryst. Growth 310, 2746 (2008).

    Article  CAS  Google Scholar 

  13. S.W. King, R.F. Davis, and R.J. Nemanich: Gas source molecular beam epitaxy of scandium nitride on silicon carbide and gallium nitride surfaces. J. Vac. Sci. Technol., A 32, 061504 (2014).

    Article  Google Scholar 

  14. S.W. King, R.J. Nemanich, and R.J. Davis: Valence and conduction band alignment at ScN interfaces with 3C-SiC (111) and 2H-GaN (0001). Appl. Phys. Lett. 105, 081606 (2014).

    Article  Google Scholar 

  15. Y. Oshima, E.G. Villora, and K. Shimamura: Hydride vapor phase epitaxy and characterization of high-quality ScN epilayers. J. Appl. Phys. 115, 153508 (2014).

    Article  Google Scholar 

  16. S. Kerdsongpanya, B. Alling, and P. Eklund: Effect of point defects on the electronic density of states of ScN studied by first-principles calculations and implications for thermoelectric properties. Phys. Rev. B 86, 195140 (2012).

    Article  Google Scholar 

  17. M.A. Moram, T.B. Joyce, P.R. Chalker, Z.H. Barber, and C.J. Humphreys: Microstructure of epitaxial scandium nitride films grown on silicon. Appl. Surf. Sci. 252, 8385 (2006).

    Article  CAS  Google Scholar 

  18. M.A. Moram, M.J. Kappers, and C.J. Humphreys: Low dislocation density nonpolar (11–20) GaN films achieved using scandium nitride interlayers. Phys. Status Solidi C 7, 1778 (2010).

    Article  CAS  Google Scholar 

  19. M.A. Moram, Y. Zhang, M.J. Kappers, Z.H. Barber, and C.J. Humphreys: Dislocation reduction in gallium nitride films using scandium nitride interlayers. Appl. Phys. Lett. 91, 152101 (2007).

    Article  Google Scholar 

  20. M. Zebarjadi, Z. Bian, R. Singh, A. Shakouri, R. Wortman, V. Rawat, and T. Sands: Thermoelectric transport in a ZrN/ScN superlattice. J. Electron. Mater. 38, 960 (2009).

    Article  CAS  Google Scholar 

  21. V. Rawat and T.D. Sands: Growth of TiN/GaN metal/semiconductor multilayers by reactive pulsed laser deposition. J. Appl. Phys. 100, 064901 (2006).

    Article  Google Scholar 

  22. V. Rawat, Y.K. Koh, D.G. Cahill, and T.D. Sands: Thermal conductivity of (Zr,W)N/ScN metal/semiconductor multilayers and superlattices. J. Appl. Phys. 105, 024909 (2009).

    Article  Google Scholar 

  23. S. Kerdsongpanya, B. Alling, and P. Eklund: Phase stability of ScN-based solid solutions for thermoelectric applications from first-principles calculations. J. Appl. Phys. 114, 073512 (2013).

    Article  Google Scholar 

  24. R. Deng, S.R. Evans, and D. Gall: Bandgap in Al1−xScxN. Appl. Phys. Lett. 102, 112103 (2013).

    Article  Google Scholar 

  25. C. Hoglund, J. Bareno, J. Birch, B. Alling, Z. Czigany, and L. Hultman: Cubic Sc1−xAlxN solid solution thin films deposited by reactive magnetron sputter epitaxy onto ScN(111). J. Appl. Phys. 105, 113517 (2009).

    Article  Google Scholar 

  26. C. Hoglund, J. Birch, B. Alling, J. Bareno, Z. Czigany, P.O.A. Persson, G. Wingqvist, A. Zukauskaite, and L. Hultman: Increased electromechanical coupling in w-ScxAl1−xN. J. Appl. Phys. 107, 1235515 (2010).

    Article  Google Scholar 

  27. M.A. Moram and S. Zhang: ScGaN and ScAlN: Emerging nitride materials. J. Mater. Chem. A 17, 6042 (2014).

    Article  Google Scholar 

  28. P.V. Burmistrova: Microstructure and thermoelectric properties of ScN thin films and metal/ScN superlattices for high-temperature energy conversion. Ph.D. Dissertation, Purdue University, West Lafayette, 2014.

  29. D. Gall, I. Petrov, P. Desjardins, and J.E. Greene: Microstructural evolution and Poisson ratio of epitaxial ScN grown on TiN(001)/MgO(001) by ultra-high vacuum reactive magnetron sputter deposition. J. Appl. Phys. 86, 5524 (1999).

    Article  CAS  Google Scholar 

  30. J.A. Stroscio, D.T. Pierce, M.D. Stiles, A. Zangwill, and L.M. Sander: Coarsening of unstable surface features during Fe (001) homoepitaxy. Phys. Rev. Lett. 75, 4246 (1995).

    Article  CAS  Google Scholar 

  31. B.W. Karr, I. Petrov, D.G. Cahill, and J.E. Greene: Morphology of epitaxial TiN(001) grown by magnetron sputtering. Appl. Phys. Lett. 70, 1703 (1997).

    Article  CAS  Google Scholar 

  32. N.E. Lee, D.G. Cahill, and J.E. Greene: Evolution of surface roughness in epitaxial Si0.7Ge0.3(001) as a function of growth temperature (200-600°C) and Si(001) substrate miscut. J. Appl. Phys. 80, 2199 (1996).

    Article  CAS  Google Scholar 

  33. G. Ehrlich and F.G. Hudda: Atomic view of surface self-diffusion: Tungsten on tungsten. J. Chem. Phys. 44, 1039 (1966).

    Article  CAS  Google Scholar 

  34. S.C. Wang and G. Ehrlich: Adatom motion to lattice steps: A direct view. Phys. Rev. Lett. 70, 41 (1993).

    Article  CAS  Google Scholar 

  35. A. Golzhauser and G. Ehrlich: Atom movement and binding on surface clusters: Pt on Pt(111) clusters. Phys. Rev. Lett. 77, 1334 (1996).

    Article  CAS  Google Scholar 

  36. F.F. Leal, S.C. Ferreira, and S.O. Ferreira: Modelling of epitaxial film growth with an Ehrlich-Schwoebel barrier dependent on the step height. J. Phys.: Condens. Matter 23, 292201 (2011).

    CAS  Google Scholar 

  37. E. Burstein: Anomalous optical absorption limit in InSb. Phys. Rev. 93, 632 (1954).

    Article  CAS  Google Scholar 

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ACKNOWLEDGMENTS

This work was funded by DARPA/Army Research Office Contract No. W911NF0810347. Research carried out in part at the Center for Functional Nanomaterials, Brookhaven National Laboratory, which is supported by the U.S. Department of Energy, Office of Basic Energy Sciences, under Contract No. DE-AC02-98CH10886.

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Correspondence to Polina V. Burmistrova.

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This author was an editor of this journal during the review and decision stage. For the JMR policy on review and publication of manuscripts authored by editors, please refer to http://www.mrs.org/jmr-editor-manuscripts/

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Burmistrova, P.V., Zakharov, D.N., Favaloro, T. et al. Effect of deposition pressure on the microstructure and thermoelectric properties of epitaxial ScN(001) thin films sputtered onto MgO(001) substrates. Journal of Materials Research 30, 626–634 (2015). https://doi.org/10.1557/jmr.2015.30

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