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Dislocations as quantum wires: Buffer leakage in AlGaN/GaN heterostructures

Published online by Cambridge University Press:  24 April 2013

C. Lewis Reynolds Jr.*
Affiliation:
Department of Materials Science and Engineering, North Carolina State University, Raleigh, North Carolina 27695
Judith G. Reynolds*
Affiliation:
Department of Physics, North Carolina State University, Raleigh, North Carolina 27695
Antonio Crespo
Affiliation:
Air Force Research Laboratory, Sensors Directorate, Wright-Patterson AFB, Ohio 45433
James K. Gillespie
Affiliation:
Air Force Research Laboratory, Sensors Directorate, Wright-Patterson AFB, Ohio 45433
Kelson D. Chabak
Affiliation:
Air Force Research Laboratory, Sensors Directorate, Wright-Patterson AFB, Ohio 45433
Robert F. Davis
Affiliation:
Department of Materials Science and Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213
*
a)Address all correspondence to this author. e-mail: [email protected]
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Abstract

Buffer leakage in aluminum gallium nitride/gallium nitride (AlGaN/GaN) heterostructure transistors is recognized as an issue that has deleterious consequences on device performance for high-power, high-frequency transistors and has been related to the presence of uncharged threading screw dislocations. In this study, we demonstrate that measurements of buffer leakage in AlGaN/GaN heterostructures grown on bulk gallium nitride (GaN) substrates are consistent with a mechanism based on the concept of dislocations acting as quantum wires in series with unintentional silicon (Si) impurity incorporation at the bulk GaN substrate/GaN buffer interface. The number of electronic channels N deduced from the leakage data using Landauer’s formula for the quantum resistance of N electronic channels is consistent with the number of dislocations along the ohmic contact pads determined from panchromatic cathodoluminescence and x-ray diffraction measurements of the dislocation density. This mechanism is consistent with Shockley’s suggestion that dislocations can act as one-dimensional conductors due to the presence of edge states along the dislocation core.

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Articles
Copyright
Copyright © Materials Research Society 2013 

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References

REFERENCES

Storm, D.F., Katzer, D.S., Binari, S.C., Shanabrook, B.V., Zhou, L., and Smith, D.J.: Effect of Al/N ratio during nucleation layer growth on Hall mobility and buffer leakage of molecular-beam epitaxy grown AlGaN/GaN heterostructures. Appl. Phys. Lett. 85, 3786 (2004).CrossRefGoogle Scholar
Poblenz, C., Waltereit, P., Rajan, S., Mishra, U.K., Speck, J.S., Chin, P., Smorchkova, I., and Heying, B.: Effect of AlN nucleation layer growth conditions on buffer leakage in AlGaN/GaN high electron mobility transistors grown by molecular beam epitaxy (MBE). J. Vac. Sci. Technol., B 23, 1562 (2005).CrossRefGoogle Scholar
Zhou, L., Smith, D.J., Storm, D.F., Katzer, D.S., Binari, S.C., and Shanabrook, B.V.: Effect of Al/N flux ratio during nucleation layer growth on the microstructure of GaN films grown by molecular-beam epitaxy. Appl. Phys. Lett. 88, 011916 (2006).CrossRefGoogle Scholar
Cao, Y., Zimmermann, T., Xing, H., and Jena, D.: Polarization-engineered removal of buffer leakage for GaN transistors. Appl. Phys. Lett. 96, 042102 (2010).CrossRefGoogle Scholar
Saito, W., Noda, T., Kuraguchi, M., Takada, Y., Tsuda, K., Saito, Y., Omura, I., and Yamaguchi, M.: Effect of buffer layer structure on drain leakage current and current collapse phenomena in high-voltage GaN-HEMTs. IEEE Trans. Electron. Dev. 56, 1371 (2009).Google Scholar
Shockley, W.: Dislocations and edge states in the diamond crystal structure. Phys. Rev. 91, 228 (1953).Google Scholar
Shockley, W.: Do dislocations hold technological promise? Solid State Technol. 26, 75 (1983).Google Scholar
Wang, A.S.: Analysis of shorts using the channel characteristics of field-effect transistors, in Solid State Electronics Laboratory Reports #SU-SSEL-76-018 (Stanford Electronics Laboratories, Stanford University, Stanford, CA, 1976).Google Scholar
Kioseoglou, J., Kalesaki, E., Belabbas, I., Chen, J., Nouet, G., Kirmse, H., Neumann, W., Komninou, P.H., and Karakostas, T.H.: Effect of doping on screw threading dislocations in AlN and their role as conductive nanowires, in Paper PB1.31, 9th International Conference on Nitride Semiconductors, Glasgow, 2011.Google Scholar
Ikuhara, Y.: Nanowire design by dislocation technology. Prog. Mater. Sci. 54, 770 (2009).CrossRefGoogle Scholar
Grenko, J.A., Ebert, C.W., Reynolds, C.L. Jr., Johnson, M.A.L., Hanser, A.D., Preble, E.A., Paskova, T., and Evans, K.R.: Modulation of mobility in homoepitaxially grown AlGaN/GaN heterostructures. Phys. Status Solidi C 6, S1037 (2009).CrossRefGoogle Scholar
Grenko, J.A., Ebert, C.W., Reynolds, C.L. Jr., Duscher, G.J., Barlage, D.W., Johnson, M.A.L., Preble, E.A., Paskova, T., and Evans, K.R.: Optimization of homoepitaxially grown AlGaN/GaN heterostructures. Phys. Status Solidi A 207, 2292 (2010).CrossRefGoogle Scholar
Zhirnov, V.: Fundamental Scaling Limits. Lecture (North Carolina State University, Raleigh, NC, 2012).Google Scholar
Hanson, G.W.: Fundamentals of Nanoelectronics (Pearson Prentice Hall, Upper Saddle River, NJ, 2008), pp 332335.Google Scholar
Lee, S.R., West, A.M., Allerman, A.A., Waldrip, K.E., Follstaedt, D.M., Provencio, P.P., Koleske, D.D., and Abernathy, C.R.: Effect of threading dislocations on the Bragg peakwidths of GaN, AlGaN, and AlN interlayers. Appl. Phys. Lett. 86, 241904 (2005).Google Scholar
Grenko, J.A., Reynolds, C.L. Jr., Barlage, D.W., Johnson, M.A.L., Lappi, S.E., Ebert, C.W., Preble, E.A., Paskova, T., and Evans, K.R.: Physical properties of AlGaN/GaN heterostructures grown on vicinal substrates. J. Electron. Mater. 39, 504 (2010).CrossRefGoogle Scholar
Xin, Y., Pennycook, S.J., Browning, N.D., Nellist, P.D., Sivananthan, S., Omnes, F., Beaumont, B., Faurie, J.P., and Gibart, P.: Direct observation of the core structure in threading dislocations in GaN. Appl. Phys. Lett. 72, 2680 (1998).CrossRefGoogle Scholar
Jones, R., Elsner, J., Haugh, M., Gutierrez, R., Frauenheim, T., Heggie, M.I., Oberg, S., and Briddon, P.R.: Interaction of oxygen with threading dislocations in GaN. Phys. Status. Solidi A 171, 167(1999).3.0.CO;2-M>CrossRefGoogle Scholar
Lahiri, J., Lin, Y., Bozkurt, P., Oleynik, I.I., and Batzill, M.: An extended defect in graphene acting as a metallic wire. Nat. Nanotechnol. 5, 326 (2010).CrossRefGoogle Scholar
Hsu, J.W.P., Manfra, M.J., Lang, D.V., Richter, S., Chu, S.N.G., Sargent, A.M., Kleiman, R.N., and Pfeiffer, L.N.: Inhomogeneous spatial distribution of reverse bias leakage in GaN Schottky diodes. Appl. Phys. Lett. 78, 1685 (2001).CrossRefGoogle Scholar
Fujiwara, H., Naruoka, H., Konishi, M., Hamada, K., Katsuno, T., Ishikawa, T., Watanabe, Y., and Endo, T.: Relationship between threading dislocation and leakage current in 4H-SiC diodes. Appl. Phys. Lett. 100, 242102 (2012).CrossRefGoogle Scholar
Simpkins, B.S., Yu, E.T., Waltereit, P., and Speck, J.S.: Correlated scanning Kelvin probe and conductive atomic force microscopy studies of dislocations in gallium nitride. J. Appl. Phys. 94, 1448 (2003).CrossRefGoogle Scholar