Examination of Film Thickness Dependence on Acoustic Impedance of Gold and Chromium Thin Films by Scanning Acoustic Microscopy

Yıl 2021, , 505 - 510, 01.09.2021

Bükem Tanören

https://doi.org/10.7240/jeps.943771

Öz

Thickness induced changes in acoustic impedance of gold (Au) and chromium (Cr) thin films are studied with scanning acoustic microscopy (SAM). Thin films are produced by thermal evaporation technique on BK7 glass substrates with varying thicknesses between 40 nm to 200 nm. In acoustic impedance (AI) mode, the microscope generates two-dimensional acoustic impedance maps of the thin films and micrometer resolution helps determining the surface defects on these films. On the other hand, acoustic impedance value is found to increase as thickness increases for both Au and Cr thin films indicating increased elasticity, therefore, hardness. The mean and standard deviation values of acoustic impedance of Cr thin films were found as 1.901 ± 0.050 MRayl for 40 nm, 1.905 ± 0.045 MRayl for 80 nm, 1.943 ± 0.049 MRayl for 120 nm, 1.964 ± 0.049 MRayl for 160 nm and 1.987 ± 0.052 MRayl for 200 nm. The mean and standard deviation values of acoustic impedance of Au thin films were found as 1.725 ± 0.026 MRayl for 80 nm and 1.954 ± 0.047 MRayl for 200 nm. This success achieved by SAM, demonstrates its potential in monitoring thin film surfaces even with very small thicknesses.

Anahtar Kelimeler

Acoustic microscopy, gold thin films, chromium thin films

Proje Numarası

2009K120520

Kaynakça

• [1] Coppa, B.J., Fulton, C.C., Kiesel, S.M., Davis, R.F., Pandarinath, C., Burnette, J. E., Nemanich, R.J., Smith, D. J. (2005). Structural, microstructural, and electrical properties of gold films and Schottky contacts on remote plasma-cleaned, n-type ZnO{0001} surfaces. Journal of Applied Physics, 97, 103517.
• [2] Catledge, S.A., Vaid, R., Diggins, IV P., Weimer, J.J., Koopman, M., Vohra, Y.K. (2011). Improved adhesion of ultra-hard carbon films on cobalt–chromium orthopaedic implant alloy. Journal of Materials Science:Materials in Medicine, 22, 307–316.
• [3] Udachan, S.L., Ayachit, N.H., Udachan, L.A. (2019). Impact of substrates on the electrical properties of thin chromium films. Ingenieria University, 23(2).
• [4] Hurley, D.C., Shen, K., Jennett, N.M., Turner, J.A. (2003). Atomic force acoustic microscopy methods to determine thin-film elastic properties. Journal of Applied Physics, 94, 2347.
• [5] Kim, M., Choi, N., Kim, Y., Lee, Y. (2018). Characterization of RF sputtered zinc oxide thin films on silicon using scanning acoustic microscopy. Journal of Electroceramics, 40, 79–87.
• [6] Guzelcimen, F., Tanoren, B., Cetinkaya, C., Donmez Kaya, M., Efkere, H.I., Ozen, Y., Bingol, D., Sirkeci, M., Kınacı, B., Unlu, M.B., Ozçelik, S. (2020). The effect of thickness on surface structure of rf sputtered TiO2 thin films by XPS, SEM/EDS, AFM and SAM. Vacuum, 182, 109766.
• [7] Passeri, D., Bettucci, A., Rossi, M. (2010). Acoustics and atomic force microscopy for the mechanical characterization of thin films. Analytical and Bioanalytical Chemistry, 396, 2769–2783.
• [8] Kumar, K.D.A., Ganesh, V., Shkir, M., AlFaify, S., Valanarasu, S. (2018). Effect of different solvents on the key structural, optical and electronic properties of sol–gel dip coated AZO nanostructured thin films for optoelectronic applications. Journal of Materials Science: Materials in Electrononics, 29, 887–897.
• [9] Tait, J.G., Merckx, T., Li, W., Wong, C., Gehlhaar, R., Cheyns, D., Turbiez, M., Heremans, P. (2015). Determination of Solvent Systems for Blade Coating Thin Film Photovoltaics. Advanced Functional Materials, 25(22), 3393-3398.
• [10] Koumoulos, E.P., Markakis, V., Tsikourkitoudi, V.P., Charitidis, C.A., Papadopoulos, N., Hristoforou, E. (2015). Tribological characterization of chemical vapor deposited Co and Co3O4 thin films for sensing reliability in engineering applications. Tribology International, 82(A), 89-94.
• [11] Arya, S.K., Saha, S., Ramirez-Vick, J.E., Gupta, V., Bhansali, S., Singh, S.P. (2012). Recent advances in ZnO nanostructures and thin films for biosensor applications: Review. Anaytica Chimica Acta, 737, 1-2.
• [12] Sawabu, M., Ohashi, M., Ohashi, K., Miyagawa, M., Kubota, T., Takanashi, K. (2017). The electrical resistivity of epitaxially deposited chromium films. Journal of Physics:Conference Series, 871, 012002.
• [13] Raghavan, R., Harzer, T.P., Djaziri, S., Hieke, S.W., Kirchlechner, C., Dehm, G. (2017). Maintaining strength in supersaturated copper–chromium thin films annealed at 0.5 of the melting temperature of Cu. Journal of Material Science, 52, 913–920.
• [14] Zhang, R., Olin, H. (2014). Porous Gold Films—A Short Review on Recent Progress. Materials, 7, 3834-3854.
• [15] Kobayashi, K., Yoshida, S., Saijo, Y., Hozumi, N. (2014). Acoustic impedance microscopy for biological tissue characterization. Ultrasonics, 54, 1922–1928.
• [16] Dhindsa, N., Walia, J., Pathirane, J.M., Khodadad, Wong, I.W.S., Saini, S.S. (2016). Adjustable optical response of amorphous silicon nanowires integrated with thin films. Nanotechnology, 27, 145703.
• [17] Kats, M.A., Capasso, F. (2014). Ultra-thin optical interference coatings on rough and flexible substrates. Applied Physics Letters, 105, 131108.
• [18] Putz, B., Schoeppner, R.L., Glushko, O., Bahr, D.F., Cordill, M.J. (2015). Improved electro-mechanical performance of gold films on polyimide without adhesion layers. Scripta Materialia, 102, 23-26.
• [19] Kobayashi, K., Yoshida, S., Saijo, Y., Hozumi, N. (2014). Acoustic impedance microscopy for biological tissue characterization. Ultrasonics, 54, 1922-1928.
• [20] Saijo, Y., Miyakawa, T., Sasaki, H., Tanaka, M., Nitta, S. (2004). Acoustic properties of aortic aneurysm obtained with scanning acoustic microscopy. Ultrasonics, 42, 695-98.
• [21] Miura, K., Nasu, H., Yamamoto, S. (2013). Scanning acoustic microscopy for characterization of neoplastic and inflammatory lesions of lymph nodes. Scientific Reports, 3, 1255.
• [22] Masugata, H,. Mizushige, K., Senda, S., Kinoshita, A., Lu, X., Sakamoto, H., Sakamoto, S., Matsuo, H. (1999). Tissue characterization of myocardial cells by use of high-frequency acoustic microscopy: differential myocyte sound speed and its transmural variation in normal, pressure-overload hypertrophic, and amyloid myocardium. Angiology, 50(10), 837-845.
• [23] Saijo, Y., Sasaki, H., Sato, M., Nitta, S., Tanaka, M. (2000). Visualization of human umbilical vein endothelial cells by acoustic microscopy. Ultrasonics, 38, 396-399.