Abstract
A c-axis aligned crystalline indium gallium zinc oxide (CAAC-IGZO) possesses unique properties beneficial for thin-film transistors (TFTs). In this study, we investigate the effect of oxygen ratio and radio frequency (RF) power on the structural, electrical, and operational characteristics of CAAC-IGZO thin films. Films were deposited on SiO2 substrates using an RF sputtering system equipped with a target containing In, Ga, Zn, and O with a composition ratio of 1:1:1:4. The effect of oxygen percentage on the structural characteristics was analyzed by X-ray diffraction (XRD), transmission electron microscopy (TEM). The oxygen percentage in the film was found to play a crucial role in forming the CAAC-IGZO and orientation of the thin films. With increasing O2 fraction, the (009)-preferred orientation of the films improved. X-ray absorption spectroscopy also validated the improved orientations of the CAAC-IGZO with high O2 concentrations up to 70%. In terms of TFT performance, however, the device with 3.3% oxygen exhibited the best performance with a saturation mobility of 10.9 cm2 V− 1 s− 1. TFT devices were prepared at a low oxygen fraction (10%) with different RF power inputs from 100 to 250 W, where the device prepared with highest power (250 W) showed the best performance.
Graphical Abstract
Similar content being viewed by others
References
Yamazaki, S.: Crystalline oxide semiconductor using CAAC-IGZO and its application. ECS Trans. 64(10), 155–164 (2014)
Kimizuka, N.: YbFe204, and Yb2Fe307 types of structures for compounds in the ln203 and SQO~-A ~ O~-BO systems [A: Fe, Ga, or Al; B: Mg, Mn, Fe, Ni, Cu, or Zn] at temperatures over 1000°C. J. Solid State Chem. 60, 382–384 (1985)
Kunitake, H., Arasawa, R., Seki, T., Honda, R., Baba, H., Shimada, D., Kimura, H., Tokumaru, R., Atsumi, T., Kato, K., Yamazaki, S., Ohshima, K., Tsuda, K., Matsumoto, N., Koshida, T., Ohshita, S., Sawai, H., Yanagisawa, Y., Saga, S.: A c -Axis-Aligned Crystalline In-Ga-Zn Oxide FET with a gate length of 21 nm suitable for memory applications. IEEE J. Electron. Devices Soc. 7, 495–502 (2019)
Amano, S., Harada, H., Akimoto, K., Sakata, J., Nishi, T., Moriya, K., Wakimoto, K., Koyama, J., Yamazaki, S., Oikawa, Y., Ikeyama, T., Sakakura, M.: 43.4: Low power LC display using In-Ga-Zn-Oxide TFTs based on variable Frame frequency. J. Soc. Inf. Disp. 41(1), 626–629 (2010)
Miyake, H., Kaneyasu, M., Hatsumi, R., Nishi, T., Hirakata, Y., Koyama, J., Yamazaki, S., Chubachi, Y., Katayama, M.: New driving method for reducing Eye strain technology (REST) in displaying still Image using CAAC IGZO LC Display. J. Soc. Inf. Disp. 44(1), 4 (2013)
Sugisawa, N., Sasaki, T., Ushikubo, T., Ohsawa, N., Seo, S., Hatano, K., Nagata, T., Fukai, S., Murakawa, T., Yoshitomi, S., Hayakawa, M., Miyake, H., Koyama, J., Yamazaki, S., Okazaki, K., Sakakura, M.: 49.4: High-definition top-emitting AMOLED display with highly Reliable Oxide Semiconductor Field Effect transistors. J. Soc. Inf. Disp. 42(1), 722–725 (2011)
Yang, C.S., Smith, L.L., Arthur, C.B., Parsons, G.N.: Stability of low-temperature amorphous silicon thin film transistors formed on glass and transparent plastic substrates. J. Vac Sci. Technol. B. 18(2), 683–689 (2000)
Dimitrakopoulos, C.D.: Organic thin-film transistors a review of recent advances. IBM J. Res. Dev. 45(1), 11–27 (2001)
Dimitrakopoulos, C.D., Malenfant, P.R.L.: Organic Thin Film transistors for large Area Electronics. Adv. Mater. 14(2), 99–117 (2002)
Seo, Y.-T., Lee, M.-S., Kim, C.-H., Woo, S.Y., Bae, J.-H., Park, B.-G., Lee, J.-H.: Si-Based FET-Type synaptic device with short-term and long-term plasticity using High-κ gate-stack. IEEE Trans. Electron. Devices. 66(2), 917–923 (2019)
Scho¨n, J.H., Kloc, S.B.C., Batlogg, B.: Ambipolar Pentacene Field-Effect transistors and inverters. Science. 287(5455), 1022–1023 (2000)
Zhang, Y., Eguchi, R., Hamao, S., Okamoto, H., Goto, H., Kubozono, Y.: Evaluation of effective field-effect mobility in Thin-Film and single-crystal transistors for revisiting various phenacene-type molecules. ACS Omega. 7(6), 5495–5501 (2022)
Nomura, K., Hosono, H.O.A.T.T.K.: Room-temperature fabrication of transparent flexible thin-film transistor using amorphous oxide swemiconductor. J. Mater. Sci. : Mater. Electron. 432, 488–492 (2004)
Kang, Y., Cho, Y., Han, S.: Cation disorder as the major electron scattering source in crystalline InGaZnO. Appl. Phys. Lett. 102(15), 152104 (2013). 1-152104-4
Yamada, Y., Matsubayashi, D., Matsuda, S., Sato, Y., Ota, M., Ito, D., Tsubuku, M., Takahashi, M., Hirohashi, T., Sakakura, M., Yamazaki, S.: Single crystalline In–Ga–Zn oxide films grown from c-axis aligned crystalline materials and their transistor characteristics. Jpn J. Appl. Phys. 53(9), 91102–091102 (2014)
Matsuda, S., Kikuchi, E., Yamane, Y., Okazaki, Y., Yamazaki, S.: Channel length dependence of field-effect mobility ofc-axis-aligned crystalline In–Ga–Zn–O field-effect transistors. Jpn J. Appl. Phys. 54(4), 041103–041103 (2015)
Geng, G.Z., Liu, G.X., Zhang, Q., Shan, F.K., Lee, W.J., Shin, B.C., Cho, C.R.: Low operating voltage InGaZnO thin-film transistors based on Al2O3 high-k dielectrics fabricated using pulsed laser deposition. J. Korean Phys. Soc. 64(10), 1437–1440 (2014)
Zhu, B., Roach, K.E., Lynch, D.M., Chung, C., Ast, D.G., Greene, R.G., Thompson, M.O.: Effects of RF Sputtering parameters on C-axis aligned Crystalline (CAAC) InGaZnO4Films using design of experiment (DOE) Approach. ECS J. Solid State Sci. Technol. 5(6), P368–P375 (2016)
Yamazaki, S., Hirohashi, T., Takahashi, M., Adachi, S., Tsubuku, M., Koezuka, J., Okazaki, K., Kanzaki, Y., Matsukizono, H., Kaneko, S., Mori, S., Matsuo, T.: Back-channel-etched thin-film transistor using c-axis-aligned crystal In-Ga-Zn oxide. J. Soc. Inf. Disp. 22(1), 55–67 (2014)
Wang, X., Shen, Z., Li, J., Wu, S.: Preparation and properties of Crystalline IGZO Thin films. Membranes. 11(2), 1341–1349 (2021)
Shin, Y., Kim, S.T., Kim, K., Kim, M.Y., Oh, S., Jeong, J.K.: The mobility enhancement of Indium Gallium Zinc Oxide transistors via low-temperature crystallization using a Tantalum Catalytic Layer. Sci. Rep. 7(1), 108851–108810 (2017)
Lynch, D.M., Zhu, B., Levin, B.D.A., Muller, D.A., Ast, D.G., Greene, R.G., Thompson, M.O.: Characterization of reactively sputtered c-axis aligned nanocrystalline InGaZnO4. Appl. Phys. Lett. 105(26), 262103–262103 (2014)
Yamazaki, S., Suzawa, H., Inoue, K., Kato, K., Hirohashi, T., Okazaki, K., Kimizuka, N.: Properties of crystalline In–Ga–Zn-oxide semiconductor and its transistor characteristics. Jpn J. Appl. Phys. 53(4S), 04ED18–04ED18 (2014)
Kang, Y., Lee, S., Sim, H., Sohn, C.H., Park, W.G., Song, S.J., Kim, U.K., Hwang, C.S., Han, S., Cho, D.-Y.: The impact of orbital hybridization on the electronic structure of crystalline InGaZnO: A new perspective on the compositional dependence. J. Mater. Chem. C. 2(43), 9196–9204 (2014)
Cho, D.-Y., Song, J., Hwang, C.S.: Effects of oxygen addition on the local structures of cosputtered transparent conducting oxide films. J. Phys. Chem. C. 113(47), 20463–20466 (2009)
Cho, D.-Y., Song, J., Na, K.D., Hwang, C.S., Jeong, J.H., Jeong, J.K., Mo, Y.-G.: Local structure and conduction mechanism in amorphous In–Ga–Zn–O films. Appl. Phys. Lett. 94(11), 112112–112112 (2009)
Jeong, H.-S., Cha, H.-S., Hwang, S.-H., Lee, D.-H., Song, S.-H., Kwon, H.-I.: Effects of Oxygen Content on operational characteristics and Stability of High-Mobility IGTO Thin-Film transistors during Channel Layer Deposition. Coatings. 11(6), 698–698 (2021)
Feng, Z., Lu, L., Wang, S., Li, J., Xia, Z., Kwok, H.S., Wong, M.: Fluorination-enabled monolithic integration of enhancement- and Depletion-Mode Indium-Gallium-Zinc Oxide TFTs. IEEE Electron. Device Lett. 39(5), 692–695 (2018)
Kang, Y., Lee, W., Kim, J., Keum, K., Kang, S.-H., Jo, J.-W., Park, S.K., Kim, Y.-H.: Effects of crystalline structure of IGZO thin films on the electrical and photo-stability of metal-oxide thin-film transistors. Mater. Res. Bull. 139, 111252–111252 (2021)
Nomura, K., Takagi, A., Kamiya, T., Ohta, H., Hirano, M., Hosono, H.: Amorphous Oxide Semiconductors for High-Performance Flexible Thin-Film transistors. Jpn J. Appl. Phys. 45(5B), 4303–4308 (2006)
Kamiya, T., Hosono, H.: Material characteristics and applications of transparent amorphous oxide semiconductors. NPG Asia Mater. 2(1), 15–22 (2010)
Mativenga, M., Um, J., Jang, J.: Reduction of Bias and Light instability of mixed Oxide Thin-Film transistors. Appl. Sci. 7(9), 885–885 (2017)
Glushkova, A.V., Dekkers, H.F.W., Nag, M., del Agua Borniquel, J.I., Ramalingam, J., Genoe, J., Heremans, P., Rolin, C.: Systematic study on the Amorphous, C-Axis-Aligned Crystalline, and Protocrystalline Phases in In–Ga–Zn Oxide Thin-Film transistors. ACS Appl. Electron. Mater. 3(3), 1268–1278 (2021)
Murugan, B., Lee, S.Y.: Effects of change of oxygen vacancy on hysteresis voltage and stability under time-temperature dependence positive bias stress in amorphous SZTO transistors. Microelectron. Eng. 253, 111678–111678 (2022)
Jeong, J.H., Park, H.W.Y.J.-S., Jeong, J.K., Mo, Y.-G.: Jaewon Song, and Cheol Seong Hwang, Origin of Subthreshold Swing Improvement in Amorphous Indium Gallium Zinc Oxide transistors. Electrochem. Solid-State Lett. 11(6), H157–H159 (2008)
Besser, R.S., a., P.J.L.: Chemical Etch Rate of plasma-enhanced Chemical Vapor Deposited Si02 films: Effect of Deposition parameters. J. Electrochem. Soc. 144(8), 2858–2864 (1997)
Shi, J., Dong, C., Dai, W., Wu, J., Chen, Y., Zhan, R.: The influence of RF power on the electrical properties of sputtered amorphous In—Ga—Zn—O thin films and devices. J. Semicond. 34(8), 084003–084003 (2013)
Chiang, H.Q., McFarlane, B.R., Hong, D., Presley, R.E., Wager, J.F.: Processing effects on the stability of amorphous indium gallium zinc oxide thin-film transistors. J. Non-Cryst Solids. 354(19–25), 2826–2830 (2008)
Acknowledgements
This work was supported by a National Research Foundation of Korea (NRF) grant and the Korean government (2018R1A6A1A03024334 and 2022M3F3A2A03015405). The authors also appreciate the financial support by Samsung Display.
Author information
Authors and Affiliations
Corresponding authors
Ethics declarations
Conflict of Interest
The authors declare that they have no conflict of interests.
Additional information
Publisher’s Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Rights and permissions
Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.
About this article
Cite this article
Cho, J., Jo, J., Patil, P.R. et al. Optimization of Sputtering Parameters and Their Effect on Structural and Electrical Properties of CAAC-IGZO Thin-Film Transistors. Electron. Mater. Lett. (2023). https://doi.org/10.1007/s13391-023-00472-x
Received:
Accepted:
Published:
DOI: https://doi.org/10.1007/s13391-023-00472-x