Characteristics and Mechanism of Catalyst-Referred Etching Method: Application to 4H-SiC
Pho Van Bui, Yasuhisa Sano, Yoshitada Morikawa, and Kazuto Yamauchi†
Department of Precision Science and Technology, Graduate School of Engineering, Osaka University
2-1 Yamada-Oka, Suita, Osaka 565-00817, Japan
A novel abrasive-free planarization method named catalyst-referred etching (CARE) was developed. A polishing pad is coated with a catalytic material to promote chemical etching of the work substrate. During processing, the topmost areas of the work substrate, which are in contact with the catalyst surface, are selectively etched off. Atomically highly ordered surfaces are obtained for many types of work substrates. In this paper, the removal characteristics and mechanism of CARE for single crystalline 4H-SiC are reviewed.
-  W. Qian, M. Skowronski, G. Augustine, R. C. Glass, H. McD. Hobgood, and R. H. Hopkins, “Characterization of Polishing-Related Surface Damage in (0001) Silicon Carbide Substrates,” J. Electrochem. Soc., Vol.142, pp. 4290-4294, 1995.
-  J. A. Powell and D. J. Larkin, “Process-Induced Morphological Defects in Epitaxial CVD Silicon Carbide,” Phys. Status Solidi B, Vol.202, pp. 529-548, 1997.
-  M. Kikuchi, Y. Takahashi, T. Suga, S. Suzuki, and Y. Bando, “Mechanochemical Polishing of Silicon Carbide Single Crystal with Chromium(III) Oxide Abrasive,” J. Am. Ceram. Soc., Vol.75, pp. 189-194, 1992.
-  H. Hara, Y. Sano, H. Mimura, K. Arima, A. Kubota, K. Yagi, J. Murata, and K. Yamauchi, “Novel abrasive-free planarization of 4H-SiC(0001) using catalyst,” J. Electron. Mater., Vol.35, p. L11, 2006.
-  K. Arima, H. Hara, J. Murata, T. Ishida, R. Okamoto, K. Yagi, Y. Sano, H. Mimura, and K. Yamauchi, “Atomic-scale flattening of SiC surfaces by electroless chemical etching in HF solution with Pt catalyst,” Appl. Phys. Lett., Vol.90, p. 202106, 2007.
-  H. Hara, Y. Morikawa, Y. Sano, and K. Yamauchi, “Termination dependence of surface stacking at 4H-SiC(0001)-1x1: density functional theory calculations,” Phys. Rev. B, Vol.79, p. 153306, 2009.
-  T. Okamoto, Y. Sano, H. Hara, T. Hatayama, K. Arima, K. Yagi, J. Murata, S. Sadakuni, K. Tachibana, Y. Shirasawa, H. Mimura, T. Fuyuki, and K. Yamauchi, “Reduction of Surface Roughness of 4H-SiC by Catalyst-Referred Etching,” Mater. Sci. Forum, Vol.645-648, pp. 775-778, 2010.
-  T. Okamoto, Y. Sano, K. Tachibana, K. Arima, A. Hattori, K. Yagi, J. Murata, S. Sadakuni, and K. Yamauchi, “Dependence of Process Characteristics on Atomic-Step Density in Catalyst-Referred Etching of 4H-SiC(0001) Surface,” J. Nanosci. Nanotechnol., Vol.11, p. 2928, 2011.
-  T. Okamoto, Y. Sano, K. Tachibana, P. V. Bui, K. Arima, K. Inagaki, K. Yagi, J. Murata, S. Sadakuni, H. Asano, A. Isohashi, and K. Yamauchi, “Improvement of Removal Rate in Abrasive-Free Planarization of 4H-SiC Substrates Using Catalytic Platinum and Hydrofluoric Acid,” Jpn. J. Appl. Phys., Vol.51, p. 046501, 2012.
-  P. V. Bui, S. Sadakuni, T. Okamoto, R. Sagawa, K. Arima, Y. Sano, and K. Yamauchi, “High-resolution TEM observation of 4H-SiC(0001) surface planarized by catalyst-referred etching,” Mater. Sci. Forum, Vol.717-720, pp. 873-876, 2012.
-  P. V. Bui, K. Inagaki, Y. Sano, K. Yamauchi, and Y. Morikawa, “Adsorption of hydrogenfluoride on SiC surfaces: A density functional theory study,” Cur. Appl. Phys., Vol.12, pp. S42-S46, 2012.
-  P. V. Bui, A. Isohashi, H. Kizaki, Y. Sano, K. Yamauchi, Y. Morikawa, and K. Inagaki, “Study on the mechanism of platinum-assisted hydrofluoric acid etching of SiC using density functional theory calculations,” Appl. Phys. Lett., Vol.107, pp. 201601, 2015.
-  A. Isohashi, Y. Sano, S. Sadakuni, and K. Yamauchi, “4H-SiC Planarization Using Catalyst-Referred Etching with Pure Water,” Mater. Sci. Forum, Vol.778-780, pp. 722-725, 2014.
-  A. Isohashi, P. V. Bui, D. Toh, S. Matsuyama, Y. Sano, K. Inagaki, Y. Morikawa, and K. Yamauchi, “Chemical etching of silicon carbide in pure water by using platinum catalyst,” Appl. Phys. Lett., Vol.110, p. 201601, 2017.
-  T. Aaltonen, M. Ritala, T. Sajavaara, J. Keinonen, and M. Leskelä, “Atomic Layer Deposition of Platinum Thin Films,” Chem. Mater., Vol.15, pp. 1924-1928, 2003.
-  T. Hayashi, Y. Morikawa, and H. Nozoye, “Adsorption state of dimethyl disulfide on Au (111): Evidence for adsorption as thiolate at the bridge site,” J. Chem. Phys., Vol.114, pp. 7615-7621, 2001.
-  Y. Morikawa, “Adsorption geometries and vibrational modes of C2H2 on the Si(001) surface,” Phys. Rev. B, Vol.63, p. 033405, 2001.
-  J. P. Perdew, K. Burke, and M. Ernzerhof, “Generalized gradient approximation made simple,” Phys. Rev. Lett., Vol.77, pp. 3865-3868, 1996.
-  D. Vanderbilt, “Soft self-consistent pseudopotentials in a generalized eigen-value formalism,” Phys. Rev. B, Vol.41, p. 7892, 1990.
-  G. Mills, H. Jónsson, and G. K. Schenter, “Reversible work transition state theory: application to dissociative adsorption of hydrogen,” Surf. Sci., Vol.324, pp. 305-337, 1994.
-  G. Henkelman, B. P. Uberuaga, and H. Jónsson, “A climbing image nudged elastic band method for finding saddle points and minimum energy paths,” J. Chem. Phys., Vol.113, pp. 9901-9904, 2000.
-  C. Chuit, R. J. P. Corriu, C. Reye, and J. C. Young, “Reactivity of penta-and hexacoordinate silicon compounds and their role as reaction intermediates,” Chem. Rev., Vol.93, pp. 1371-1448, 1993.
-  M. Benaglia, S. Guizzetti, and L. Pignataro, “Stereoselective reactions involving hypervalent silicate complexes,” Coord. Chem. Rev., Vol.252, pp. 492-512, 2008.
-  Y. Hoshimoto, H. Yabuki, R. Kumar, H. Suzuki, M. Ohashi, and S. Ogoshi, “Highly Efficient Activation of Organosilanes with η2-Aldehyde Nickel Complexes: Key for Catalytic Syntheses of Aryl-, Vinyl-, and Alkynyl-Benzoxasiloles,” J. Am. Chem. Soc., Vol.136, pp. 16752-16755, 2014.
-  S. Rendler and M. Oestreich, “Hypervalent Silicon as a Reactive Site in Selective Bond-Forming Processes,” Synthesis, Vol.11, pp. 1727-1747, 2005.
-  Y. Orito and M. Nakajima, “Lewis Base Catalyzed Asymmetric Reactions Involving Hypervalent Silicate Intermediates,” Synthesis, Vol.9, pp. 1391-1401, 2006.
-  T. Katsuno, Y. Watanabe, H. Fujiwara, M. Konishi, H. Naruoka, J. Morimoto, T. Morino, and T. Endo, “Analysis of surface morphology at leakage current sources of 4H-SiC Schottky barrier diodes,” Appl. Phys. Lett., Vol.98, p. 222111, 2011.
-  T. Katsuno, Y. Watanabe, H. Fujiwara, M. Konishi, T. Yamamoto, and T. Endo, “Effects of Surface and Crystalline Defects on Reverse Characteristics of 4H-SiC Junction Barrier Schottky Diodes,” Jpn. J. Appl. Phys., Vol.50, p. 04DP04, 2011.
-  P. G. Neudeck and J. A. Powell, “Performance Limiting Micropipe Defects in Silicon Carbide Wafers,” IEEE Electron Device Lett., Vol.15, pp. 63-65, 1994.
-  B. Chen, H. Matsuhata, T. Sekiguchi, K. Ichinoseki, and H. Okumura, “Surface defects and accompanying imperfections in 4H-SiC: Optical, structural and electrical characterization,” Acta Mater., Vol.60, pp. 51-58, 2012.
-  T. Kimoto, “Material science and device physics in SiC technology for high-voltage power devices,” Jpn. J. Appl. Phys., Vol.54, p. 040103, 2015.
-  O. Ishiyama, K. Yamada, H. Sako, K. Tamura, M. Kitabatake, J. Senzaki, and H. Matsuhata, “Gate oxide reliability on trapezoid-shaped defects and obtuse triangular defects in 4H-SiC epitaxial wafers,” Jpn. J. Appl. Phys., Vol.53, p. 04EP15, 2014.
-  H. Fujikawa, A. Onogi, T. Katsuno, T. Morino, T. Endo, and Y. Sano, “Improvement of I-V Characteristics of Schottky Barrier Diode by 4H-SiC Surface Planarization,” Mater. Sci. Forum, Vol.821-823, pp. 567-570, 2015.
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