Effect of substrate temperature on structural, morphological, and optical properties of Gallium Oxide thin films deposited by RF-Sputtering

Year 2024, , 1498 - 1507, 01.09.2024

Fevkani Yıldız , Hülya Akçay , Aykut Astam , Mutlu Kundakçı

https://doi.org/10.35378/gujs.1275066

Abstract

In this paper, gallium oxide (Ga2O3) thin films at various substrate temperatures (Ts) were grown on Indium Tin Oxide (ITO), glass, p-type silicon by radio-frequency magnetron sputtering (RFMS). We investigated how structural, morphological and optical properties change with various Ts. XRD results of thin films grown on p-type silicon substrate suggest that crystallinity properties of synthesized thin films strongly depend on the Ts. From SEM and AFM analyses of Ga2O3 thin films grown on p-type silicon substrate, it was observed that when the temperature increased, a porous structure appeared, and the grain size changed depending on the Ts. Moreover, obtained results from the absorption measurements, the bandgap energy of Ga2O3 thin films grown on the p-type silicon substrate decreased with increasing substrate temperature.

Keywords

Gallium oxide, Thin film, Sputter, Nano structure

References

• [1] Pearton, S., Yang, J., Cary, P. H., Ren, F., Kim, J., Tadjer, M. J., Mastro. M. A., "A review of Ga2O3 materials, processing, and devices", Applied Physics Reviews, 5(1): 011301, (2018).
• [2] Ji, Z., Du, J., Fan J., Wang, W., "Gallium oxide films for filter and solar-blind UV detector", Optical Materials, 28(4): 415-417, (2006).
• [3] Mobtakeri, S., Akaltun, Y., Özer, A., Kılıç, M., Tüzemen, E. Ş., Gür, E., "Gallium oxide films deposition by RF magnetron sputtering; a detailed analysis on the effects of deposition pressure and sputtering power and annealing", Ceramics International, 47(2): 1721-1727, (2021).
• [4] Passlack, M., Schubert, E. F., Hobson, W., Hong, M., Moriya, N., Chu, S. N. G., Konstadinidis, K., Mannaerts, J., Schnoes, M., Zydzik. G., "Ga2O3 films for electronic and optoelectronic applications", Journal of Applied Physics, 77(2): 686-693, (1995).
• [5] King, P., McKenzie, I., Veal A. T., "Observation of shallow-donor muonium in Ga2O3: Evidence for hydrogen-induced conductivity", Applied Physics Letters, 96(6): 062110, (2010).
• [6] Green, A. J., Speck, J., Xing, G., Moens, P., Allerstam, F., Gumaelius, K., Neyer, T., Arias-Purdue, A., Mehrotra V., Kuramata, A. J., Sasaki, K., Watanabe, S., Koshi, K., Blevins, J., Bierwagen, O., Krishnamoorthy, S., Leedy, K., Arehart, A. R., Neal, A. T., Mou, S., Ringel, S. A., Kumar, A., Sharma, A., Ghosh, K., Singisetti, U., Li, W., Chabak, K., Liddy, K., Islam, A., Rajan, S., Graham, S., Choi, S., Cheng, Z., Higashiwaki, M.,"β-Gallium oxide power electronics", APL Materials, 10(2): 029201, (2022).
• [7] Bhosle, V., Prater, J., Yang, F., Burk, D., Forrest S., Narayan, J., "Gallium-doped zinc oxide films as transparent electrodes for organic solar cell applications", Journal of Applied Physics, 102(2): 023501, (2007).
• [8] Stenzel, O. “The physics of thin film optical spectra”, Berlin/Heidelberg, Germany: Springer, (2015).
• [9] Bartic, M., Baban, C. I., Suzuki, H., Ogita, M., Isai, M., "β‐gallium oxide as oxygen gas sensors at a high temperature", Journal of the American Ceramic Society, 90(9): 2879-2884, (2007).
• [10] Ortiz, A., Alonso, J., Andrade, E., Urbiola, C., "Structural and optical characteristics of gallium oxide thin films deposited by ultrasonic spray pyrolysis", Journal of The Electrochemical Society, 148(2): F26, (2001).
• [11] Liu, Q., Guo, D., Chen, K., Su, Y., Wang, S., Li, P., Tang, W., "Stabilizing the metastable γ phase in Ga2O3 thin films by Cu doping", Journal of Alloys and Compounds, 731: 1225-1229, (2018).
• [12] Miyata, T., Nakatani, T., Minami, T., "Gallium oxide as host material for multicolor emitting phosphors", Journal of Luminescence, 87: 1183-1185, (2000).
• [13] Hao, J., Lou, Z., Renaud, I., Cocivera, M., "Electroluminescence of europium-doped gallium oxide thin films", Thin Solid Films, 467(1-2): 182-185, (2004).
• [14] Kim, H. W., Kim, N. H., "Growth of gallium oxide thin films on silicon by the metal organic chemical vapor deposition method", Materials Science and Engineering: B, 110(1): 34-37, (2004).
• [15] Oshima, T., Okuno, T., Fujita, S., "Ga2O3 thin film growth on c-plane sapphire substrates by molecular beam epitaxy for deep-ultraviolet photodetectors", Japanese Journal of Applied Physics, 46(11R): 7217, (2007).
• [16] Miyata, T., Nakatani, T., Minami, T., "Gallium oxide as host material for multicolor emitting phosphors", Journal of Luminescence, 87: 1183-1185, (2000).
• [17] Liao, Y., Jiao, S., Li, S., Wang, J., Wang, D., Gao, S., Yu, Q., Li, H., "Effect of deposition pressure on the structural and optical properties of Ga2O3 films obtained by thermal post-crystallization", CrystEngComm, 20(1): 133-139, (2018).
• [18] Mobtakeri, S., Tuzemen, E. S., Özer, A., Gür, E., “Characterization of Gallium Oxide/glass thin films grown by RF magnetron sputtering”, Cumhuriyet Science Journal, 41(4), 929-937, (2020).
• [19] Kumar, S. S., Rubio, E. J., Noor-A-Alam, M., Martinez, G., Manandhar, S., Shutthanandan, V., Ramana, C. V. “Structure, morphology, and optical properties of amorphous and nanocrystalline gallium oxide thin films”, The Journal of Physical Chemistry C, 117(8), 4194-4200, (2013).
• [20] Patterson, A. L., "The Scherrer formula for X-ray particle size determination", Physical Review Journal, 56(10): 978, (1939).
• [21] Jiao, S., Lu, H., Wang, X., Nie, Y., Wang, D., Gao, S., Wang, J., “The structural and photoelectrical properties of gallium oxide thin film grown by radio frequency magnetron sputtering”, ECS Journal of Solid State Science and Technology, 8(7), Q3086, (2019).
• [22] Ramana, C. V., Rubio, E. J., Barraza, C. D., Miranda Gallardo, A., McPeak, S., Kotru, S., Grant, J. T., “Chemical bonding, optical constants, and electrical resistivity of sputter-deposited gallium oxide thin films”, Journal of Applied Physics, 115(4), (2014).
• [23] Stenzel, O., “The physics of thin film optical spectra”, Springer, (2015).
• [24] Tauc, J., Menth, A., “States in the gap", Journal of Non-Crystalline Solids”, 8: 569-585, (1972).
• [25] Gullapalli, S., Vemuri, R., Ramana, C., "Structural transformation induced changes in the optical properties of nanocrystalline tungsten oxide thin films", Applied Physics Letters, 96(17): 171903, (2010).
• [26] Tyagi, P., Vedeshwar, A., "Effect of residual stress on the optical properties of CdI 2 films", Physical Review B, 66(7): 075422, (2002).
• [27] Zhou, X., Heigl, F., Ko, J., Murphy, M., Zhou, J., Regier, T., Blyth, R., Sham, T., "Origin of luminescence from Ga2O3 nanostructures studied using x-ray absorption and luminescence spectroscopy", Physical Review B, 75(12): 125303, (2007).
• [28] Battu, A. K., Ramana, C. V., "Mechanical properties of nanocrystalline and amorphous gallium oxide thin films", Advanced Engineering Materials, 20(11): 1701033, (2018).