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Understanding gaas Native Oxides By Correlating Three Liquid Contact Angle Analysis (3LCAA) and High Resolution Ion Beam Analysis (HR-IBA) to X-Ray Photoelectron Spectroscopy (XPS) as Function of Surface Processing

  • Sukesh Ram (a1) (a2) (a3), Amber A. Chow (a1) (a2), Shaurya Khanna (a1) (a2), Nikhil C. Suresh (a1) (a2) (a3), Franscesca J. Ark (a1) (a2), Saaketh R. Narayan (a1) (a2) (a3), Aashi R. Gurijala (a1) (a2), Jack M. Day (a1) (a2) (a3), Timothy Karcher (a1) (a4), Robert J. Culbertson (a1), Shawn D. Whaley (a1) (a2), Karen L. Kavanagh (a5) and Nicole Herbots (a1) (a2) (a3)...


Chemical bonding in native oxides of GaAs, before and after etching, is detected by X-Ray Photoelectron Spectroscopy (XPS). It is correlated with surface energy engineering (SEE), measured via Three Liquid Contact Angle Analysis (3LCAA), and oxygen coverage, measured by High Resolution Ion Beam Analysis (HR-IBA).

Before etching, GaAs native oxides are found to be hydrophobic with an average surface energy, γT, of 33 ± 1 mJ/m2, as measured by 3LCAA. After dilute NH4OH etching, GaAs becomes highly hydrophilic and its surface energy, γT, increases by a factor 2 to a reproducible value of 66 ± 1 mJ/m2. Using HR-IBA, oxygen coverage on GaAs is found to decrease from 7.2 ± 0.5 monolayers (ML) to 3.6 ± 0.5 ML. The 1.17 ratio of Ga to As, measured by HR-IBA, remains constant after etching.

XPS is used to measure oxidation of Ga and As, as well as surface stoichiometry on two locations of several GaAs(100) wafers before and after etching. The relative proportions of Ga and As are unaffected by adventitious carbon contamination. The 1.16 Ga:As ratio, measured by XPS, matches HR-IBA analysis. The proportions of oxidized Ga and As do not change significantly after etching. However, the initial ratio of As2O5 to As2O3, within the oxidized As, significantly decreases after etching from approximately 3:1 to 3:2.

Absolute oxygen coverage, as a function of surface processing, is determined within 0.5 ML by HR-IBA. XPS offers insight into these modifications by detecting electronic states and phase composition changes of GaAs oxides. The changes in surface chemistry are correlated to changes in hydro-affinity and surface energies measured by 3LCAA.


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[1]Leng, Y. X. et al. , IEEE Conference Record - Abstracts. 2002 IEEE International Conference on Plasma Science (Cat. No.02CH37340), Banff, Alberta, Canada, 2002, pp. 308
[2]Morita, M., Ohmi, T., Hasegawa, E., Kawakami, M., Ohwada, M.., Journal of Applied Physics. 68, 1272 (1990).
[3]Helms, CR. In: Balk P, editor. The Si-SiO2 system. Amsterdam, Oxford, New York, Tokyo: Elsevier, (1988).
[4]Lewis, E.A. and Irene, E.A., J. Vac. Sci. Technol., 4, 916 (1986).
[5]Deal, B. E.; Grove, A. S., Journal of Applied Physics. 36 (12): 37703778 (1965).
[6]Mizokawa, O. Komoda, and Miyase, S., Thin Solid Films 156, 127 (1988).
[7]Schwartz, G. P., Gualtieri, G. J., Kammiott, G. W., and Schwartz, B., J. Electrochem. Soc. 126,1737 (1979).
[8]Vancauwenberghe, O., Herbots, N., Manoharan, H., Ahrens, M., J. Vac. Sci. Technol. 9(3), P. 1035 (1991).
[9]"New South Innovations News - UNSW breaks solar cell record". NewSouth Innovations. 2008-11-18. Archived from the original on April 25, 2012. Retrieved 2018-06-23.
[10]Frank, D., et al. , IEEE Journal of Photovoltaics. 6: 343349. (2016).
[11]Khan, I. M., et al. , Optoelectronics and Advanced Materials-Rapid Communications. 9(1):107-109 (2014).
[12]Herbots, N., Shaw, J., Hurst, Q., Grams, M., Culbertson, R., Smith, D. J., Atluri, V., Zimmerman, P., and Queeney, K., Matls. Sci. Eng. B 87, 303 (2001).
[13]Queeney, K. T., Herbots, N., Shaw, J. M., Atluri, V., and Chabal, Y. J., Appl. Physics Letters 84, 493 (2004).
[14]Shaw, Justin M., Herbots, N., Hurst, Q. B., Bradley, D., Culbertson, R. J., Atluri, V., and Queeney, K. T., Journal of Applied Physics 100, 104109 (2006).
[15]Herbots, N., Xing, Q., Hart, M., Bradley, J. D., Sell, D. A., Culbertson, R. J., & Wilkens, B. J. Nucl. Instr. and Meth. in Physics Research, Section B: 272, 330-333 (2012).
[16]Herbots, N., Atluri, V. P., Bradley, J. D., Swati, B., Hurst, Q. B., and Xiang, J., U.S. Patent N° 6,613,677 (Granted September 2, 2003).
[17]Herbots, N, Bradley, J.D., Shaw, J.M., Culbertson, R J., Atluri, V. US Patent N° 7,851,365 (14 December 14, 2010).
[18]Kern, W., J. Electrochem. Soc. 137, 1887 (1990).
[19]Kern, W., RCA Rev. 31, 187 (1970).
[20]Herbots, N., Culbertson, R. J., Bradley, J. D., Hart, M. A., Sell, David A., Whaley, Shawn D., US Patent N° 9,018,077 (28 April 2015)
[21]Herbots, N, Whaley, S. D., Culbertson, R.J., Bennett-Kennett, R., M Murphy, A., Bade, M. T., Farmer, S., Watson, C. F., Acharya, A., US Patent N° 9,589,801 (7 March 2017).
[22]Bennett-Kennett, R., Wet: Catalyzing Molecular Cross-Bridges and Interphases Between Nanoscopically Smoothed Si-Based Surfaces And Tailoring Surface Energy Components, Senior Thesis, Arizona State University, Dept. of Physics (2013).
[23]Davis, E. W., Wet NanobondingTM Of Semiconducting Surfaces Optimized Via Surface Energy Modification Using Three Liquid Contact Angle Analysis as A Metrology, Senior Thesis Arizona State University, Dept. of Physics (2016).
[24]Whaley, S. D., Nano-Bonding of Silicon Oxides-based surfaces at Low Temperature: Bonding Interphase Modeling via Molecular Dynamics and Characterization of Bonding Surfaces Topography, Hydro-affinity and Free Energy (Arizona State University, Physics, PhD Doctoral Dissertation, 2011).
[25]Cornejo, C. E., Bertram, M. E., Diaz, T. C., Narayan, S. R., Ram, S., Kavanagh, K. L., Herbots, N., Day, J. M., Ark, F. J., Dhamdhere, A., Culbertson, R. J. and Islam, R.. MRS Advances, 3(57-58), 3403-3411 (2018).
[26]Narayan, S., Day, J., Thinakaran, H., Herbots, N., Bertram, M., Cornejo, C., Diaz, T., Kavanagh, K., Culbertson, R. J., Ark, F., Ram, S., Mangus, M., Islam, R.. MRS Advances, 3(57-58), 3379-3390 (2018).
[27]Oss, C. J. V., Chaudhury, M. K., and Good, R. J., Chemical Reviews 88, 927 (1988).
[28]Faibish, R., Yoshida, W., and Cohen, Y., J. of Colloid and Interface Sci., Vol. 256, Issue 2, p. 341 (2002)
[29]Carre, A., J. Adhesion Sci. Technol., 21 (10), 961-981 (2007).
[30]Mayer, M., American Inst. Phys. Conf. Proceedings 475, p. 541 (1999).
[31]CasaXPS Manual 2.3.15 Introduction to XPS and AES, Casa Software Ltd (2009).
[32]Characterization of Oxidized GaAs Wafers by XPS, Evans Analytical Group, LLC (2007).
[33]Engelhard, M. H., et al. , Surface Science Spectra 23, 83 (2016).
[34]Helsen, L., Van den Bulck, E., Van Bael, M.K., Vanhoyland, G., Mullens, J., Thermo. Acta 414.145153. (2004).
[35]Rebaud, M., Roure, M.C. Loup, V., Rodriguez, Ph., Martinez, E., Besson, P., Electrochem Soc. Transactions, 69 (8) 243-250 (2015)



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