Rare Earth Oxide Surface Modification of Porous SiO2 Film Prepared by Atomic Layer Deposition

doi:10.15541/jim20240433

Abstract

Abstract:

Broadband transparent films play a pivotal role in various applications such as lenses and solar cells, particularly porous structured transparent films exhibit significant potential. This study investigates a porous SiO₂ refractive index gradient anti-reflective film prepared by atomic layer deposition (ALD). A porous SiO₂ film with gradual porosity was obtained by phosphoric acid etching of Al₂O₃/SiO₂ multilayers with gradient Al₂O₃ ratios, achieving a gradual decrease in refractive index from the substrate to the surface. The film exhibited an average transmittance as high as 97.8% within the wavelength range from 320 nm to 1200 nm. The environmental adaptability was further enhanced by surface modification using rare earth oxide (REO) La₂O₃, resulting in formation of a lotus leaf-like structure and achieving a water contact angle of 100.0°. These data proved that the modification significantly improved hydrophobic self-cleaning capability while maintaining exceptional transparency of the film. The surface structure of the modified film remained undamaged even after undergoing wipe testing, demonstrating its excellent surface durability.

Key words: porous SiO₂, rare earth oxide, atomic layer deposition, anti-reflective, self-cleaning

CLC Number:

TB43

JIN Jianfei, LÜ Lin, LI Ying, YAN Lu, CAO Yunzhen, LI Wei. Rare Earth Oxide Surface Modification of Porous SiO₂ Film Prepared by Atomic Layer Deposition[J]. Journal of Inorganic Materials, 2025, 40(9): 1029-1036.

Figures/Tables 10

Table 1 Preparation parameters of films

Material	First reactant (pulse time)	First purge (purge time)	Second reactant (pulse time)	Second purge (purge time)	Deposition temperature/℃
Al₂O₃	TMA (0.15 s)	N₂ (1.5 s)	H₂O (0.1 s)	N₂ (1.5 s)	350
SiO₂	DIPAS (0.10 s)	N₂ (1.5 s)	O₃ (1.0 s)	N₂ (1.5 s)	350
La₂O₃	La(ⁱPrfAMD)₃ (0.10 s)	N₂(1.5 s)	Plasma-O₂ (5.0 s)	N₂ (1.5 s)	250

Fig. 1 Diagram of the film structure (a) Schematic diagram of the Al2O3/SiO2 multilayers with gradient Al2O3 ratios; (b) 3D structure of NP SiO2 film with a gradient index

Fig. 2 SEM images after acid etching of Al2O3/SiO2 multilayers with thickness ratios at (a) 2 : 2, (b) 3 : 2, (c) 4 : 2, and (d) 5 : 2

Fig. 3 FE-SEM images of cross sections and diagram of films (a-c) Acid etching for (a) 3, (b) 9 and (c) 24 h; (d) Schematic diagram of acid etching conjecture Al2O3/SiO2 layers; (e) Different thickness of SiO2 layer in Al2O3/SiO2 films after acid etching for 24 h; (f) Deposition diagram of SiO2 layers with different thicknesses Colorful figures are available on website

Fig. 4 Performance of NP SiO2 films with different Al2O3/SiO2 thickness ratios (a) Refractive index at 580 nm; (b) Transmittance curves. Colorful figures are available on website

Fig. 5 WCA test result of NP SiO2 films

Fig. 6 Morphology and performance of the film (a) 45° cross-section morphology of NP SiO2 films with La2O3 modification; (b) Transmittance curves of different samples

Fig. 7 SEM images and WCA test results (a, b) La2O3 film on SiO2 glass; (c, d) La2O3 film on NP SiO2 films; (e, f) Fogging results of (e) freeze test and (f) steam test

Fig. 8 Results of the wipe resistance test (a) NP SiO2 films; (b) La2O3-modified NP SiO2 films; (c) WCA test result of La2O3-modified NP SiO2 films after being wiped

Fig. S1 XPS spectra of La2O3 layer (a) Wide-scan spectrum; (b) La3+3d spectrum

References 48

[1]	RAY N J, YOO J H, NGUYEN H T, et al. All-glass metasurfaces for ultra-broadband and large acceptance angle antireflectivity: from ultraviolet to mid-infrared. Advanced Optical Materials, 2023, 11(12): 2300137.
[2]	WU J, TU J, LI L, et al. Gradient refractive index-based broadband antireflective coatings and application in silicon solar modules. Surfaces and Interfaces, 2022, 30: 101918.
[3]	SUN X, HU K, TU J, et al. Design and preparation of superhydrophobic, broadband and double-layer antireflective coatings. Surfaces and Interfaces, 2021, 24: 101135.
[4]	RUUD C J, CLERI A, MARIA J P, et al. Ultralow index SiO₂ antireflection coatings produced via magnetron sputtering. Nano Letters, 2022, 22(18): 7358.
[5]	LI Y, ZHANG J, ZHU S, et al. Biomimetic surfaces for high- performance optics. Advanced Materials, 2009, 21(46): 4731.
[6]	DONG S, ZHANG J, JIAO H, et al. Nanopillars assisted multilayer antireflection coating for photovoltaics with multiple bandgaps. Applied Physics Letters, 2019, 115(13): 133106.
[7]	KIM S H, LEE S H, YU J S. Broadband and antireflective characteristics of glancing angle deposited titanium dioxide nanostructures for photovoltaic applications. Thin Solid Films, 2019, 685: 53.
[8]	XI J Q, KIM J K, SCHUBERT E F. Silica nanorod-array films with very low refractive indices. Nano Letters, 2005, 5(7): 1385. PMID
[9]	TAO C, ZOU X, REDDY K M, et al. A hydrophobic ultralow refractive-index silica coating towards double-layer broadband antireflective coating with exceptionally high vacuum stability and laser-induced damage threshold. Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2019, 563: 340.
[10]	YE L, LI L, WANG X, et al. Template-free synthesis of uniform hollow silica nanoparticles for controllable antireflection coatings. Ceramics International, 2020, 46(6): 7453.
[11]	GHAZARYAN L, KLEY E B, TUNNERMANN A, et al. Nanoporous SiO₂ thin films made by atomic layer deposition and atomic etching. Nanotechnology, 2016, 27(25): 255603.
[12]	GHAZARYAN L, SEKMAN Y, SCHRÖDER S, et al. On the properties of nanoporous SiO₂ films for single layer antireflection coating. Advanced Engineering Materials, 2019, 21(6): 1801229.
[13]	GHAZARYAN L, KLEY E B, TÜNNERMANN A, et al. Composite materials and nanoporous thin layers made by atomic layer deposition. Optical Systems Design 2015: Advances in Optical Thin Films V, 2015, 9627: 96270P.
[14]	SEKMAN Y, FELDE N, GHAZARYAN L, et al. Light scattering characterization of single-layer nanoporous SiO₂ antireflection coating in visible light. Applied Optics, 2020, 59(5): A143.
[15]	CEBECI F Ç, WU Z Z, ZHAI L. Nanoporosity-driven superhydrophilicity: a means to create multifunctional antifogging coatings. Langmuir, 2006, 22: 2856.
[16]	CHEN J, ZHANG L, ZENG Z, et al. Facile fabrication of antifogging, antireflective, and self-cleaning transparent silica thin coatings. Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2016, 509: 149.
[17]	PFEIFFER K, GHAZARYAN L, SCHULZ U, et al. Wide-angle broadband antireflection coatings prepared by atomic layer deposition. ACS Applied Materials & Interfaces, 2019, 11(24): 21887.
[18]	WANG X, ZHAO H, CAO Y, et al. Surface free energy and microstructure dependent environmental stability of Sol-Gel SiO₂ antireflective coatings: effect of combined vapor phase surface treatment. Journal of Colloid and Interface Science, 2019, 555: 124.
[19]	AZIMI G, DHIMAN R, KWON H M, et al. Hydrophobicity of rare-earth oxide ceramics. Nature Materials, 2013, 12(4): 315. DOI PMID
[20]	KUJAWA J, AL-GHARABLI S, WRZESZCZ G, et al. Physicochemical and magnetic properties of functionalized lanthanide oxides with enhanced hydrophobicity. Applied Surface Science, 2021, 542: 148563.
[21]	TAN X, ZHU D, SHI Z, et al. Thickness-dependent morphology, microstructure, adsorption and surface free energy of sputtered CeO₂ films. Ceramics International, 2020, 46(9): 13925.
[22]	LV Q, ZHANG S, DENG S, et al. Transparent and water repellent ceria film grown by atomic layer deposition. Surface and Coatings Technology, 2017, 320: 190.
[23]	KULAH E, MAROT L, STEINER R, et al. Surface chemistry of rare-earth oxide surfaces at ambient conditions: reactions with water and hydrocarbons. Scientific Reports, 2017, 7: 43369.
[24]	OH J, OREJON D, PARK W, et al. The apparent surface free energy of rare earth oxides is governed by hydrocarbon adsorption. iScience, 2022, 25(1): 103691.
[25]	OH I K, ZENG L, KIM J E, et al. Surface energy change of atomic-scale metal oxide thin films by phase transformation. ACS Nano, 2020, 14(1): 676.
[26]	FU S P, ROSSERO J, CHEN C, et al. On the wetting behavior of ceria thin films grown by pulsed laser deposition. Applied Physics Letters, 2017, 110(8): 081601.
[27]	XU P, MENG G, PERSHIN L, et al. Control of the hydrophobicity of rare earth oxide coatings deposited by solution precursor plasma spray by hydrocarbon adsorption. Journal of Materials Science & Technology, 2021, 62: 107.
[28]	ZHAO B, MATTELAER F, RAMPELBERG G, et al. Thermal and plasma-enhanced atomic layer deposition of yttrium oxide films and the properties of water wettability. ACS Applied Materials & Interfaces, 2020, 12(2): 3179.
[29]	OH I K, KIM K, LEE Z, et al. Hydrophobicity of rare earth oxides grown by atomic layer deposition. Chemistry of Materials, 2014, 27(1): 148.
[30]	PARK K C, CHOI H, CHANG C H, et al. Nanotextured silica surfaces with robust superhydrophobicity and omnidirectional broadband supertransmissivity. ACS Nano, 2012, 6: 3789.
[31]	SON J, KUNDU S, VERMA L K, et al. A practical superhydrophilic self cleaning and antireflective surface for outdoor photovoltaic applications. Solar Energy Materials and Solar Cells, 2012, 98: 46.
[32]	WANG D, WANG Z, ZHANG Z, et al. Both antireflection and superhydrophobicity structures achieved by direct laser interference nanomanufacturing. Journal of Applied Physics, 2014, 115(23): 233101.
[33]	HUANG Z, CAI C, KUAI L, et al. Leaf-structure patterning for antireflective and self-cleaning surfaces on Si-based solar cells. Solar Energy, 2018, 159: 733.
[34]	HAN G, NGUYEN T B, PARK S, et al. Moth-eye mimicking solid slippery glass surface with icephobicity, transparency, and self- healing. ACS Nano, 2020, 14(8): 10198.
[35]	KIM J Y, KIM H C, WALLACE R M, et al. In situ XPS study on ALD (atomic layer deposition) of high-k dielectrics La₂O₃ using La-formidinate and ozone. ECS Transactions, 2012, 45(3): 95.
[36]	LEE B, PARK T J, HANDE A, et al. Electrical properties of atomic-layer-deposited La₂O₃ films using a novel La formamidinate precursor and ozone. Microelectronic Engineering, 2009, 86(7/8/9): 1658.
[37]	YANG Z Y, ZHU D Q, LU D S, et al. The relationship between porous ratio and refractive index in nanoporous film. Acta Optica Sinica, 2003, 23(1366): 1366.
[38]	ESHAGHI A, MOJAB M. Fabrication of antireflective antifogging nano-porous silica thin film on glass substrate by layer-by-layer assembly method. Journal of Non-Crystalline Solids, 2014, 405: 148.
[39]	TAM J, PALUMBO G, ERB U, et al. Robust hydrophobic rare earth oxide composite electrodeposits. Advanced Materials Interfaces, 2017, 4(24): 1700850.
[40]	LUNDY R, BYRNE C, BOGAN J, et al. Exploring the role of adsorption and surface state on the hydrophobicity of rare earth oxides. ACS Applied Materials & Interfaces, 2017, 9(15): 13751.
[41]	OH S, SHIM J, SEO D, et al. Organic/inorganic hybrid cerium oxide-based superhydrophobic surface with enhanced weather resistance and self-recovery. Progress in Organic Coatings, 2022, 170: 106998.
[42]	XU P, COYLE T W, PERSHIN L, et al. Understanding the correlations between the mechanical robustness, coating structures and surface composition for highly-/super-hydrophobic ceramic coatings. Surface and Coatings Technology, 2019, 378: 124929.
[43]	PRAKASH S, GHOSH S, PATRA A, et al. Intrinsic hydrophilic nature of epitaxial thin-film of rare-earth oxide grown by pulsed laser deposition. Nanoscale, 2018, 10(7): 3356. DOI PMID
[44]	CHEN P Y, HADAMEK T, KWON S, et al. Role of template layers for heteroepitaxial growth of lanthanum oxide on GaN(0001) via atomic layer deposition. Journal of Vacuum Science & Technology A, 2020, 38(1): 012403.
[45]	PUURUNEN R L, VANDERVORST W. Island growth as a growth mode in atomic layer deposition: a phenomenological model. Journal of Applied Physics, 2004, 96(12): 7686.
[46]	GEORGE S M. Atomic layer deposition: an overview. Chemical Reviews, 2010, 110(1): 111. DOI PMID
[47]	AYTUG T, LUPINI A R, JELLISON G E, et al. Monolithic graded-refractive-index glass-based antireflective coatings: broadband/ omnidirectional light harvesting and self-cleaning characteristics. Journal of Materials Chemistry C, 2015, 3(21): 5440.
[48]	ZHANG C, KALULU M, SUN S, et al. Environmentally safe, durable and transparent superhydrophobic coating prepared by one-step spraying. Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2019, 570: 147.

Rare Earth Oxide Surface Modification of Porous SiO₂ Film Prepared by Atomic Layer Deposition

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