Abstract: Multicomponent oxide (Ga_xIn_1−x)₂O₃ films are prepared on (0001) sapphire substrates to realize a tunable band-gap by magnetron sputtering technology followed by thermal annealing. The optical properties and band structure evolution over the whole range of compositions in ternary compounds (Ga_xIn_1−x)₂O₃ are investigated in detail. The X-ray diffraction spectra clearly indicate that (Ga_xIn_1−x)₂O₃ films with Ga content varying from 0.11 to 0.55 have both cubic and monoclinic structures, and that for films with Ga content higher than 0.74, only the monoclinic structure appears. The transmittance of all films is greater than 86% in the visible range with sharp absorption edges and clear fringes. In addition, a blue shift of ultraviolet absorption edges from 380 to 250 nm is noted with increasing Ga content, indicating increasing band-gap energy from 3.61 to 4.64 eV. The experimental results lay a foundation for the application of transparent conductive compound (Ga_xIn_1−x)₂O₃ thin films in photoelectric and photovoltaic industry, especially in display, light-emitting diode, and solar cell applications.

磁控溅射法生长的带隙可调谐(Ga_xIn_1−x)₂O₃

[1]Abdullah SA, Sahdan MZ, Nafarizal N, et al., 2018. Influence of substrate annealing on inducing Ti³⁺ and oxygen vacancy in TiO₂ thin films deposited via RF magnetron sputtering. Appl Surf Sci, 462:575-582.

[2]Baldini M, Gogova D, Irmscher K, et al., 2014. Heteroepitaxy of Ga_2(1−x)In_2xO₃ layers by MOVPE with two different oxygen sources. Cryst Res Technol, 49(8):552-557.

[3]Beji N, Souli M, Reghima M, et al., 2016. Study on the physical properties of europium doped indium oxide thin films. Mater Sci Semicond Process, 56:20-28.

[4]Bellaiche L, Mattila T, Wang LW, et al., 1999. Resonant hole localization and anomalous optical bowing in InGaN alloys. Appl Phys Lett, 74:1842.

[5]Cabello G, Lillo L, Caro C, et al., 2008. Structure and optical characterization of photochemically prepared ZrO₂ thin films doped with erbium and europium. J Non-Cryst Sol, 354(33):3919-3928.

[6]Chang TH, Chang SJ, Chiu CJ, et al., 2015a. Bandgap-engineered in indium-gallium-oxide ultraviolet phototransistors. IEEE Photon Technol Lett, 27(8):915-918.

[7]Chang TH, Chang SJ, Weng WY, et al., 2015b. Amorphous indium–gallium–oxide UV photodetectors. IEEE Photon Technol Lett, 27(19):2083-2086.

[8]Chen F, Ding S, Su WT, 2019. The synthesis and tunable optical properties of two-dimensional alloyed Mo_1−xW_xS₂ monolayer with in-plane composition modulations (0≤x≤1). J Alloys Compd, 784:213-219.

[9]Chen KY, Yang CC, Su YK, et al., 2019. Impact of oxygen vacancy on the photo-electrical properties of In₂O₃-based thin-film transistor by doping Ga. Materials, 12(5):737.

[10]Chen ZM, Zhuo Y, Tu WB, et al., 2017. Highly ultraviolet transparent textured indium tin oxide thin films and the application in light emitting diodes. Appl Phys Lett, 110(24):242101.

[11]Demin IE, Kozlov AG, 2017. Effect of composition on properties of In₂O₃–Ga₂O₃ thin films. J Phys Conf Ser, 858:012009.

[12]Hassa A, von Wenckstern H, Splith D, et al., 2019. Structural, optical, and electrical properties of orthorhombic κ-(In_xGa_1−x)₂O₃ thin films. APL Mater, 7(2):022525.

[13]Hsu CM, Tzou WC, Yang CF, et al., 2015. Investigation of the high mobility IGZO thin films by using co-sputtering method. Materials, 8(5):2769-2781.

[14]Jiang FX, Xu XH, Zhang J, et al., 2011. Room temperature ferromagnetism in metallic and insulating (In_1−xFe_x)₂O₃ thin films. J Appl Phys, 109(5):053907.

[15]Jothibas M, Manoharan C, Ramalingam S, et al., 2014. Spectroscopic analysis, structural, microstructural, optical and electrical properties of Zn-doped In₂O₃ thin films. Spectrochim Acta A Mol Biomol Spectrosc, 122: 171-178.

[16]Kang J, Tongay S, Li JB, et al., 2013. Monolayer semiconducting transition metal dichalcogenide alloys: stability and band bowing. J Appl Phys, 113(14):143703.

[17]Kokubun Y, Abe T, Nakagomi S, 2010. Sol-gel prepared (Ga_1−xIn_x)₂O₃ thin films for solar-blind ultraviolet photodetectors. Phys Stat Sol A Appl Mater Sci, 207(7):1741-1745.

[18]Kranert C, Lenzner J, Jenderka M, et al., 2014. Lattice parameters and Raman-active phonon modes of (In_xGa_1–x)₂O₃ for x < 0.4. J Appl Phys, 116(1):013505.

[19]Labram JG, Treat ND, Lin YH, et al., 2016. Energy quantization in solution-processed layers of indium oxide and their application in resonant tunneling diodes. Adv Funct Mater, 26(10):1656-1663.

[20]Lee HY, Liu JT, Lee CT, 2018. Modulated Al₂O₃-alloyed Ga₂O₃ materials and deep ultraviolet photodetectors. IEEE Photon Technol Lett, 30(6):549-552.

[21]Lee SR, Wright AF, Crawford MH, et al., 1999. The band-gap bowing of Al_xGa_1−xN alloys. Appl Phys Lett, 74(22):3344.

[22]Maccioni MB, Ricci F, Fiorentini V, 2016. Properties of (Ga_1−xIn_x)₂O₃ over the whole x range. J Phys Condens Matt, 28(22):224001.

[23]Manoharan C, Jothibas M, Jeyakumar J, et al., 2015. Structural, optical and electrical properties of Zr-doped In₂O₃ thin films. Spectrochim Acta A Mol Biomol Spectrosc, 145: 47-53.

[24]Mathen JJ, Madhavan J, Thomas A, et al., 2017. Transparent ZnO–PVA binary composite for UV-A photo detector: optical, electrical and thermal properties followed by laser induced fluorescence. J Mater Sci Mater Electron, 28(10):7190-7203.

[25]Mottram DA, Lin YH, Pattanasattayavong P, et al., 2016. Quasi two-dimensional dye-sensitized In₂O₃ phototransistors for ultrahigh responsivity and photosensitivity photodetector applications. ACS Appl Mater Interf, 8(7):4894-4902.

[26]Oshima T, Kato Y, Oda M, et al., 2017. Epitaxial growth of γ-(Al_xGa_1−x)O₃ alloy films for band-gap engineering. Appl Phys Expr, 10(5):051104.

[27]Peelaers H, Steiauf D, Varley JB, et al., 2015. (In_xGa_1−x)₂O₃ alloys for transparent electronics. Phys Rev B Cover Condens Matt Mater Phys, 92(8):085206.

[28]Pourhashemi A, Farrell RM, Cohen DA, et al., 2015. High-power blue laser diodes with indium tin oxide cladding on semipolar GaN substrates. Appl Phys Lett, 106(11):111105.

[29]Premkumar M, Vadivel S, 2017. Effect of annealing temperature on structural, optical and humidity sensing properties of indium tin oxide (ITO) thin films. J Mater Sci Mater Electron, 28(12):8460-8466.

[30]Priya BS, Shanthi M, Manoharan C, et al., 2017. Hydrothermal synthesis of Ga-doped In₂O₃ nanostructure and its structural, optical and photocatalytic properties. Mater Sci Semicond Process, 71:357-365.

[31]Prozheeva V, Hölldobler R, von Wenckstern H, et al., 2018. Effects of alloy composition and Si-doping on vacancy defect formation in (In_xGa_1–x)₂O₃ thin films. J Appl Phys, 123(12):125705.

[32]Ramzan M, Kaewmaraya T, Ahuja R, 2013. Molecular dynamics study of amorphous Ga-doped In₂O₃: a promising material for phase change memory devices. Appl Phys Lett, 103(7):072113.

[33]Reddy IN, Reddy CV, Cho M, et al., 2017. Structural, optical and XPS study of thermal evaporated In₂O₃ thin films. Mater Res Expr, 4(8):086406.

[34]Schmidt-Grund R, Kranert C, Böntgen T, et al., 2014. Dielectric function in the NIR-VUV spectral range of (In_xGa_1−x)₂O₃ thin films. J Appl Phys, 116(5):053510.

[35]Senthilkumar V, Vickraman P, 2010. Annealing temperature dependent on structural, optical and electrical properties of indium oxide thin films deposited by electron beam evaporation method. Curr Appl Phys, 10(3):880-885.

[36]Suzuki N, Kaneko K, Fujita S, 2014. Growth of corundum-structured (In_xGa_1−x)₂O₃ alloy thin films on sapphire substrates with buffer layers. J Cryst Growth, 401:670-672.

[37]Tauc J, Menth A, 1972. States in the gap. J Non-Cryst Sol, 8-10: 569-585.

[38]Veeraswamy Y, Vijayakumr Y, Reddy MV, et al., 2013. Structural and optical characterization of indium oxide thin films by vacuum thermal evaporation. Int Conf on Advanced Nanomaterials & Emerging Engineering Technologies, p.502-505.

[39]von Wenckstern H, 2019. 6-properties of (In, Ga)₂O₃ alloys. In: Pearton S, Ren F, Mastro M (Eds.), Gallium Oxide. Elsevier, Amsterdam, p.119-148.

[40]von Wenckstern H, Splith D, Purfürst M, et al., 2015. Structural and optical properties of (In, Ga)₂O₃ thin films and characteristics of Schottky contacts thereon. Semicond Sci Technol, 30(2):024005.

[41]Wang X, Chen ZW, Zhang FB, et al., 2016. Influence of substrate temperature on the properties of (AlGa)₂O₃ thin films prepared by pulsed laser deposition. Ceram Int, 42(11):12783-12788.

[42]Wright AF, Nelson JS, 1995. Bowing parameters for zinc-blende Al_1−xGa_xN and Ga_1−xIn_xN. Appl Phys Lett, 66(22):3051.

[43]Yakuphanoglu F, Gunduz B, Al-Ghamdi AA, et al., 2015. Transparent ultraviolet photodiodes based conductive gallium-indium-oxide films/p-type silicon for solar panel tracking systems. Sens Actuat A Phys, 234:212-222.

[44]Yang F, Ma J, Luan C, et al., 2009. Structural and optical properties of Ga_2(1−x)In_2xO₃ films prepared on α-Al₂O₃ (0001) by MOCVD. Appl Surf Sci, 255(8):4401-4404.

[45]Zhang FB, Saito K, Tanaka T, et al., 2014. Wide bandgap engineering of (GaIn)₂O₃ films. Sol State Commun, 186:28-31.

[46]Zhang FB, Sun JY, Li HO, et al., 2019. Mixed phase (GaIn)₂O₃ films with a single absorption edge grown by magnetron sputtering. J Electron Mater, 48(12):8061-8066.