Abstract
Molten KOH etching and x-ray topography have been well established as two of the major characterization techniques used for observing as well as analyzing the various crystallographic defects in both substrates and homoepitaxial layers of silicon carbide. Regarding assessment of dislocation density in commercial wafers, though the two techniques show good consistency in threading dislocation density analysis, significant discrepancy is found in the case of basal plane dislocations (BPDs). In this paper we compare measurements of BPD densities in 4-inch 4H-SiC commercial wafers assessed using both etching and topography methods. The ratio of the BPD density calculated from topographic images to that from etch pits is estimated to be larger than 1/sinθ, where θ is the offcut angle of the wafer. Based on the orientations of the defects in the wafers, a theoretical model is put forward to explain this disparity and two main sources of errors in assessing the BPD density using chemical etching are discussed.
Similar content being viewed by others
References
P.G. Neudeck, in The VLSI Handbook (The Electrical Engineering Handbook Series), ed. by W.-K. Chen (CRC/IEEE, Boca Raton, FL, 2000), pp. 6.1–6.24
P.G. Neudeck, Mater. Sci. Forum 338–342, 1161 (2000).
St.G. Müller, in Superlattices and Microstructures, Vol. 40, (Spring Meeting of the European Materials Research Society, Nice, 2006), pp. 195–200.
Q. Wahab, A. Ellison, A. Henry, E. Janzen, C. Hallin, J. Di Persio, and R. Martinez, Appl. Phys. Lett. 76, 2725 (2000). doi:10.1063/1.126456.
R. Singh, Microelectron. Reliab. 46, 713 (2006). doi:10.1016/j.microrel.2005.10.013.
P. Bergman, H. Lendenmann, P.A. Nilsson, U. Lindefelt, and P. Skytt, Mater. Sci. Forum 353–356, 299 (2001). doi:10.4028/www.scientific.net/MSF.353-356.299.
R.E. Stahlbush, M. Fatemi, J.B. Fedison, S.D. Arthur, L.B. Rowland, and S. Wang, J. Electron. Mater. 31, 370 (2002). doi:10.1007/s11664-002-0085-8.
R.E. Stahlbush, K.X. Liu, M.E. Twigg, in IRPS Conf. Rec., (IEEE, San Jose, 2006), 26–30, pp. 90–94, doi:10.1109/RELPHY.2006.251196
V.D. Wheeler, B.L. VanMil, R.L. Myers-Ward, C.R. Eddy, R.E. Stahlbush, D.K. Gaskill, (ISDRS, Stamp College Park, MD, 2009), pp. 1–2, 9–11 doi:10.1109/ISDRS.2009.5378072
X. Zhang, M. Skowronski, K.X. Liu, R.E. Stahlbush, J.J. Sumakeris, M.J. Paisley, and M.J. O’Loughlin, J. Appl. Phys. 102, 093520 (2007). doi:10.1063/1.2809343.
W. Chen and M.A. Capano, J. Appl. Phys. 98, 114907 (2005). doi:10.1063/1.2137442.
H.Z. Song and T.S. Sudarshan, Mater. Sci. Forum 717–720, 125 (2012). doi:10.4028/www.scientific.net/MSF.717-720.125.
R.T. Bondokov, I.I. Khlebnikov, T. Lashkov, E. Tupitsyn, G. Stratiy, Y. Khlebnikov, and T.S. Sudarshan, Jpn. J. Appl. Phys. 41, 7312 (2002). doi:10.1143/JJAP.41.7312.
M. Dudley and X. Huang, Mater. Sci. Forum 338–342, 431 (2000). doi:10.4028/www.scientific.net/MSF.338-342.431.
B. Kallinger, S. Polster, P. Berwian, J. Friedrich, G. Müller, A.N. Danilewsky, A. Wehrhahn, and A.D. Weber, J. Cry-st. Growth 314, 21 (2011). doi:10.1016/j.jcrysgro.2010.10.145.
H. Tsuchida, I. Kamata, and M. Nagano, J. Cryst. Growth 306, 254 (2007). doi:10.1016/j.jcrysgro.2007.05.006.
S.A. Sakwe, R. MüllerWellmann, and P.J. Wellmann, J. Cryst. Growth 289, 520 (2006). doi:10.1016/j.jcrysgro.2005.11.096.
Y. Ishikawa, Y. Yao, Y. Sugawar, K. Danno, H. Suzuki, Y. Kawai, and N. Shibata, Mater. Sci. Forum 717–720, 367 (2012). doi:10.4028/www.scientific.net/MSF.717-720.367.
Y. Chen, Defects Structures in Silicon Carbide Bulk Crystals, Epilayers and Devices, Ph.D. Thesis. Stony Brook University, U.S. (2009) (http://hdl.handle.net/1951/45064).
A. Authier, Adv. X-ray Anal. 10, 9 (1967).
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Wang, H., Sun, S., Dudley, M. et al. Quantitative Comparison Between Dislocation Densities in Offcut 4H-SiC Wafers Measured Using Synchrotron X-ray Topography and Molten KOH Etching. J. Electron. Mater. 42, 794–798 (2013). https://doi.org/10.1007/s11664-013-2527-x
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11664-013-2527-x