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Zhang X, Wang Z, Hou P, Wu S, Lu J, Zhao X, Tian S. Facile preparation of a water-based antireflective SiO 2 film with high transmittance for perovskite solar cells. NANOSCALE 2024. [PMID: 38683134 DOI: 10.1039/d4nr00832d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/01/2024]
Abstract
The synthesis of anti-reflective (AR) films has been increasingly focused on environmental friendliness and cost efficiency in order to realize green and sustainable development. Herein, a novel strategy for preparing a nanoporous SiO2 AR film with high transmittance by a sol-gel process is proposed based on a sodium silicate aqueous solution. Sodium ions in the as-prepared SiO2 AR film can be effectively removed by a facile washing process, and thus its refractive index can be regulated. Moreover, the pH value of the sol has a huge effect on the structure and properties of the SiO2 AR film. As a result, the AR film exhibited a high transmittance increase of 4.10% at 550 nm and an average transmittance increase by 3.51% in the wavelength range of 380-1100 nm compared with blank glass. In addition, the obtained water-based SiO2 AR film exhibited hydrophilicity and the water contact angle (WCA) can be regulated from 61° to 8.4°. When the AR film was applied to the upper surface of perovskite solar cells, the photoelectric conversion efficiency (PCE) revealed an improvement of 1.44% compared with the PCE of perovskite solar cells without the AR film. Therefore, this work can provide a facile and effective method to prepare water-based antireflective films with high transmittance for solar cells.
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Affiliation(s)
- Xuemin Zhang
- State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology (WUT), No. 122, Luoshi Road, Wuhan 430070, P. R. China.
| | - Ziao Wang
- State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology (WUT), No. 122, Luoshi Road, Wuhan 430070, P. R. China.
| | - Peiran Hou
- State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology (WUT), No. 122, Luoshi Road, Wuhan 430070, P. R. China.
| | - Senwei Wu
- State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology (WUT), No. 122, Luoshi Road, Wuhan 430070, P. R. China.
| | - Jianfeng Lu
- State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology (WUT), No. 122, Luoshi Road, Wuhan 430070, P. R. China.
| | - Xiujian Zhao
- State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology (WUT), No. 122, Luoshi Road, Wuhan 430070, P. R. China.
| | - Shouqin Tian
- State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology (WUT), No. 122, Luoshi Road, Wuhan 430070, P. R. China.
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2
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Modaresialam M, Granchi N, Stehlik M, Petite C, Delegeanu S, Gourdin A, Bouabdellaoui M, Intonti F, Kerzabi B, Grosso D, Gallais L, Abbarchi M. Nano-imprint lithography of broad-band and wide-angle antireflective structures for high-power lasers. OPTICS EXPRESS 2024; 32:12967-12981. [PMID: 38571103 DOI: 10.1364/oe.518828] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Accepted: 03/08/2024] [Indexed: 04/05/2024]
Abstract
We demonstrate efficient anti reflection coatings based on adiabatic index matching obtained via nano-imprint lithography. They exhibit high total transmission, achromaticity (99.5% < T < 99.8% from 390 to 900 nm and 99% < T < 99.5% from 800 to 1600 nm) and wide angular acceptance (T > 99% up to 50 degrees). Our devices show high laser-induced damage thresholds in the sub-picosecond (>5 J/cm2 at 1030 nm, 500 fs), nanosecond (>150 J/cm2 at 1064 nm, 12 ns and >100 J/cm2 at 532 nm, 12 ns) regimes, and low absorption in the CW regime (<1.3 ppm at 1080 nm), close to those of the fused silica substrate.
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Vazquez JL, López J, Bohórquez C, Lizarraga E, Blanco E, Can-Uc B, Romo O, Nedev N, Farías MH, Tiznado H. O 3-Annealing Effect on the Etching Resilience of a TiO 2/Al 2O 3 filter Prepared by Atomic Layer Deposition. ACS APPLIED MATERIALS & INTERFACES 2023; 15:40942-40953. [PMID: 37590996 DOI: 10.1021/acsami.3c07586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/19/2023]
Abstract
This research investigates the improvements of ozone (O3) annealing on the optical and etching characteristics of TiO2/Al2O3 multilayer band-pass filters designed for potential optoelectronic applications. The band-pass filters were fabricated using atomic layer deposition (ALD), and their performance was systematically analyzed after the addition of O3 annealing at moderate temperatures (up to 300 °C). Results reveal that O3 annealing improves the optical transmittance of the multilayers by approximately 40% without significant spectral changes (∼6 nm). The observed enhancement in the transmittance is attributed to the improved stoichiometry of TiO2. By filling in the oxygen vacancies created during the fabrication process, it reduces its extinction coefficient. Furthermore, the O3 annealing enhances the stability of TiO2 against wet etching, improving the uniformity of etched surfaces. Etching on the ozone-annealed multilayer was up to 8 times more homogeneous, as observed in the roughness. The relatively short duration of the O3 annealing process, approximately 1.6 h, makes it a cost-effective alternative compared to using ozone in the ALD process, which can last several hours for thick optical coatings.
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Affiliation(s)
- Jorge Luis Vazquez
- Centro de Investigación Científica y de Educación Superior de Ensenada-CICESE. Ensenada 22860, México
- Universidad Nacional Autónoma de México (UNAM), Centro de Nanociencias y Nanotecnología (CNyN), Km 107 Carretera Tijuana-Ensenada s/n, C.P. 22800, Ensenada 04510, Baja California, México
| | - Javier López
- CONAHCYT - Centro de Nanociencias y Nanotecnología, UNAM, Km 107 Carretera Tijuana-Ensenada s/n., C.P. 22800, Ensenada 04510, México
| | - Carolina Bohórquez
- Centro de Investigación Científica y de Educación Superior de Ensenada-CICESE. Ensenada 22860, México
- Universidad Nacional Autónoma de México (UNAM), Centro de Nanociencias y Nanotecnología (CNyN), Km 107 Carretera Tijuana-Ensenada s/n, C.P. 22800, Ensenada 04510, Baja California, México
| | - Eder Lizarraga
- Universidad Autónoma de Baja California, Unidad Valle de las Palmas, Blvd. Universitario 1000, C.P. 22260 Tijuana 22260, Baja California, México
| | - Eduardo Blanco
- Departamento de Física de la Materia Condensada, Universidad de Cádiz, E11519 Puerto Real, España
| | - Bonifacio Can-Uc
- Universidad Nacional Autónoma de México (UNAM), Centro de Nanociencias y Nanotecnología (CNyN), Km 107 Carretera Tijuana-Ensenada s/n, C.P. 22800, Ensenada 04510, Baja California, México
| | - Oscar Romo
- Centro de Investigación Científica y de Educación Superior de Ensenada-CICESE. Ensenada 22860, México
- Universidad Nacional Autónoma de México (UNAM), Centro de Nanociencias y Nanotecnología (CNyN), Km 107 Carretera Tijuana-Ensenada s/n, C.P. 22800, Ensenada 04510, Baja California, México
| | - Nicola Nedev
- Universidad Autónoma de Baja California, Instituto de Ingeniería, Blvd. Benito Juárez s/n, C.P. 21280, Mexicali 21280, Baja California, México
| | - Mario H Farías
- Universidad Nacional Autónoma de México (UNAM), Centro de Nanociencias y Nanotecnología (CNyN), Km 107 Carretera Tijuana-Ensenada s/n, C.P. 22800, Ensenada 04510, Baja California, México
| | - Hugo Tiznado
- Universidad Nacional Autónoma de México (UNAM), Centro de Nanociencias y Nanotecnología (CNyN), Km 107 Carretera Tijuana-Ensenada s/n, C.P. 22800, Ensenada 04510, Baja California, México
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Astrauskytė D, Galvanauskas K, Gailevičius D, Drazdys M, Malinauskas M, Grineviciute L. Anti-Reflective Coatings Produced via Atomic Layer Deposition for Hybrid Polymer 3D Micro-Optics. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:2281. [PMID: 37630866 PMCID: PMC10458567 DOI: 10.3390/nano13162281] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Revised: 07/30/2023] [Accepted: 08/03/2023] [Indexed: 08/27/2023]
Abstract
The increasing demand for optics quality requires the lowest optical power loss, which can occur from unwanted reflections. Laser direct writing (LDW) allows for the fabrication of complex structures, which is particularly advantageous in micro-optic applications. This research demonstrates the possibility of forming an anti-reflective coating on hybrid polymer micro-lenses fabricated by employing LDW without changing their geometry. Such coating deposited via atomic layer deposition (ALD) decreased the reflection from 3.3% to 0.1% at a wavelength of 633 nm for one surface of hybrid organic-inorganic SZ2080™ material. This research validates the compatibility of ALD with LDW 3D multiphoton lithography synergistically, expanding its applications on optical grade sub-100 μm scale micro-optics.
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Affiliation(s)
- Darija Astrauskytė
- Center for Physical Sciences and Technology, Savanorių av. 231, LT-02300 Vilnius, Lithuania
| | - Karolis Galvanauskas
- Laser Research Center, Physics Faculty, Vilnius University, Saulėtekio av. 10, LT-10223 Vilnius, Lithuania
| | - Darius Gailevičius
- Laser Research Center, Physics Faculty, Vilnius University, Saulėtekio av. 10, LT-10223 Vilnius, Lithuania
| | - Mantas Drazdys
- Center for Physical Sciences and Technology, Savanorių av. 231, LT-02300 Vilnius, Lithuania
| | - Mangirdas Malinauskas
- Laser Research Center, Physics Faculty, Vilnius University, Saulėtekio av. 10, LT-10223 Vilnius, Lithuania
| | - Lina Grineviciute
- Center for Physical Sciences and Technology, Savanorių av. 231, LT-02300 Vilnius, Lithuania
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5
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Yang YT, Cai QY, Liu DQ, Gao LS, Zhang HT, Peng L, Hu ET, Liu BJ, Luo HH, Zhang RJ, Zheng YX. Low polarization-sensitive ultra-broadband anti-reflection coatings with improved reliability. OPTICS EXPRESS 2023; 31:25477-25489. [PMID: 37710433 DOI: 10.1364/oe.495646] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Accepted: 06/30/2023] [Indexed: 09/16/2023]
Abstract
Broader spectra, lower reflectivity and higher reliability are the performance requirements for broadband antireflective (BBAR) films. In this work, a BBAR film structure was proposed, which maintains extremely low reflectivity, ultra-wide spectra, low polarization sensitivity and practical reliability. The BBAR film consists of a dense multilayer interference stack on the bottom and a nano-grass-like alumina (NGLA) layer with a gradient low refractive index distribution on the top. The film was deposited by atomic layer deposition, while the NGLA layer was formed by means of a hot water bath on Al2O3 layer. The top NGLA layer has extremely high porosity and ultra-low refractive index, along with extremely fragile structure. To surmount the fragility of NGLA layer, a sub-nano layer of SiO2 was grown by atomic layer deposition to solidify its structure and also to adjust the refractive index with different thicknesses of SiO2. Finally, in the wide wavelength range of 400-1100 nm, the average transmittance of the double-sided coated fused quartz reaches 99.2%. The absorption, light scattering, reliability and polarization characteristics of BBAR films were investigated. An optimized BBAR film with low polarization-sensitivity and improved reliability was realized, which should be potentially promising for application in optical systems.
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6
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Wu J, Tu J, Yu S, Wu H, Xie Y, Yang Y, Xv Z, Zhang Q. Hollow core-shell nanocoatings with gradient refractive index structure for enhanced photovoltaic performance. Colloids Surf A Physicochem Eng Asp 2023. [DOI: 10.1016/j.colsurfa.2023.131424] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/08/2023]
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7
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Gerold K, Beladiya V, Paul P, Kästner D, Saarniheimo M, Niiranen K, Schröder S, Szeghalmi A. Conformal antireflection coatings for optical dome covers by atomic layer deposition. APPLIED OPTICS 2023; 62:B92-B96. [PMID: 37132891 DOI: 10.1364/ao.477069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Complex 3D-shaped optics are difficult to coat with conventional technologies. In this research, large top-open optical glass cubes with a 100 mm side length were functionalized to simulate large dome-shaped optics. Antireflection coatings for the visible range (420-670 nm) and for a single wavelength (550 nm) were applied by atomic layer deposition simultaneously on two and six demonstrators, respectively. Reflectance measurements on both the inner and outer glass surfaces confirm a conformal AR coating with a residual reflectance significantly below 0.3% for visible wavelengths and 0.2% for single wavelengths on nearly the entire surface of the cubes.
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8
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Schulz U, Rickelt F, Gärtner A, Bingel A. Broadband antireflection coatings with low polarization splitting. APPLIED OPTICS 2023; 62:B87-B91. [PMID: 37132890 DOI: 10.1364/ao.479539] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
A major problem for optical systems is the polarization splitting occurring at any interface in the event of oblique light. Low-index nanostructured silica layers were produced by overcoating an initial organic structure with silica and subsequent removal of the organic constituents. The nanostructured layers can be tailored to achieve defined low effective refractive indices down to 1.05. They can also be stacked together with homogeneous layers to produce broadband antireflective coatings with very low polarization splitting. Especially thin interlayers that separate the low-index structured layers turned out to be useful to optimize the polarization properties.
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9
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Sol–gel-derived bayberry-like SiO2@TiO2 multifunctional antireflective coatings for enhancing photovoltaic power generation. Colloids Surf A Physicochem Eng Asp 2022. [DOI: 10.1016/j.colsurfa.2022.130173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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10
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Wu G, Zhou Y, Hong M. Bilayer-film-decorated microsphere with suppressed interface reflection for enhanced nano-imaging. OPTICS EXPRESS 2022; 30:28279-28289. [PMID: 36299027 DOI: 10.1364/oe.456038] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Microspheres as special optical lenses have extensive applications due to their super-focusing ability and outstanding resolving power on imaging. The interface reflection between the microsphere and sample surface significantly affects nano-imaging as exhibited in the form of the Newton's rings pattern in virtual images. In this work, a new scheme of decorating the microsphere with a dielectric bilayer thin film is proposed to suppress the interface reflection and thus enhance the imaging performance. The particle swarm optimization algorithm is performed with a full-wave simulation to refine the bilayer thin film decorated microsphere design, which is successfully realized via a novel fabrication strategy. Experimental imaging results demonstrate that the Newton's rings pattern in virtual images is substantially diminished. Both the imaging contrast and effective field-of-view of the microsphere nano-imaging are improved via this effective light manipulation scheme, which is also applicable to promoting the performance of the microsphere in other optical applications.
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11
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Wang H, Yang C, Wang Y, Yuan W, Zheng T, Chen X, Liu Y, Zhang Y, Shen W. Wide-angle broadband antireflection coatings with nano-taper hydrated alumina film. OPTICS EXPRESS 2022; 30:28922-28931. [PMID: 36299078 DOI: 10.1364/oe.464327] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Accepted: 07/08/2022] [Indexed: 06/16/2023]
Abstract
Wide-angle and broadband antireflection (AR) coating is of the essence in modern optical systems in many fields, which has a great influence on the stray light and imaging quality. A simple and convenient manufacturing method is proposed to address this issue based on a composite coating combining the nano-tapered Al2O3•xH2O (AH) structure and high-low index thin film stack. The optical properties of nano-tapered AH structure at various thickness are first studied and modeled in optics by several homogeneous sub-layers with the graded equivalent index. The designed composite AR coatings are manufactured by vacuum deposition and wet etching subsequently in the hot deionized water. Compared to the common dielectric multilayer antireflection stack, the composite coating presents excellent AR performance. The measured average reflectance values of the double-side coated BK7 glass are as low as 0.40%, 0.41%, 0.56% and 3.13% in 400-1100nm band at angles of incidence (AOI) of 6°, 20°, 40°, and 60°, respectively, while the measured average transmittance at normal incidence increases up to 99.3%. Finally, the process reproductivity, environmental reliability test including long term storage, high temperature annealing and 85°C-85% relative humidity storage of the composite coatings are evaluated. The proposed AR scheme provides a low-cost, efficient, wide-angle and broadband AR coating for kinds of large-curvature components and complex surfaces in fields of consumer electronics, automotive, security, etc.
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12
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Tunable antireflective characteristics enabled by small yellow leafhopper-inspired soccer ball-shaped structure arrays. J Taiwan Inst Chem Eng 2022. [DOI: 10.1016/j.jtice.2022.104407] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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13
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Omrani M, Malekmohammad M, Zabolian H. Wide-angle broadband antireflection coatings based on boomerang-like alumina nanostructures in visible region. Sci Rep 2022; 12:904. [PMID: 35042946 PMCID: PMC8766437 DOI: 10.1038/s41598-022-04928-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Accepted: 01/03/2022] [Indexed: 11/09/2022] Open
Abstract
A novel boomerang-like alumina based antireflective coating with ultra-low reflectance has been produced for light incidence angles form 0 up to 45°. Boomerang-like alumina nanostructures have been fabricated on the BK7 glass substrates by dip-coating and surface modification via hot water treatment. To achieve the lowest residual reflectance, the effect of dip-coating rate and hot-water temperature in the treatment process has been investigated and optimized. To further investigate the boomerang-like alumina nanostructure and extract its graded refractive index profile by fitting the measured reflectance spectrum with the simulated one, a simulation based on the finite-difference time-domain (FDTD) method has been performed. The average reflectance measured at normal incidence for double-sided coated BK7 glass substrates is only 0.3% in the visible spectral region. Considering both sides, the average reflectance of the substrate decreased in the spectral range of 400-700 nm down to 0.4% at incidence angles of 45° by applying the boomerang-like alumina antireflection coatings. The optimized single layer boomerang-like alumina coating on the curved aspheric lens exhibited a low average reflectance of less than 0.14% and an average transmittance of above 99.3% at normal incidence. The presented process is a simple and cost-effective route towards broadband and omnidirectional antireflection coatings, which have promising potential to be applied on substrates having large scales with complex geometric shapes.
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Affiliation(s)
- MirKazem Omrani
- Department of Physics, University of Isfahan, P.O. Box 81746-7344, Isfahan, Iran.
| | | | - Hosein Zabolian
- Department of Physics, University of Isfahan, P.O. Box 81746-7344, Isfahan, Iran
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Kauppinen C, Pasanen TP, Isakov K, Serué M, Heinonen J, Vähänissi V, Lipsanen H, Savin H. Grass-like alumina coated window harnesses the full omnidirectional potential of black silicon photodiodes. APPLIED OPTICS 2021; 60:10415-10420. [PMID: 34807052 DOI: 10.1364/ao.442415] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Accepted: 11/01/2021] [Indexed: 06/13/2023]
Abstract
Packaged photodiodes suffer from Fresnel reflection from the package window glass, especially at high angles of incidence. This has a notable impact particularly on black silicon (b-Si) photodiodes, which have extreme sensitivity. In this work, we show that by adding a simple grass-like alumina antireflection (AR) coating on the window glass, excellent omnidirectional sensitivity and high external quantum efficiency (EQE) of b-Si photodiodes can be retained. We demonstrate that EQE increases at all angles, and up to 15% absolute increases in EQE at a 70° angle of incidence compared to conventional uncoated glass. Furthermore, even at the incidence angle of 50°, the double-sided coating provides higher EQE than bare glass at normal incidence. Our results demonstrate that grass-like alumina coatings are efficient and omnidirectional AR coatings for photodiode package windows in a wide wavelength range across the visible spectrum to near-infrared radiation.
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Li PC, Chen HY, Chiang KT, Yang H. Reversible embroidered ball-like antireflective structure arrays inspired by leafhopper wings. J Colloid Interface Sci 2021; 599:119-129. [PMID: 33933786 DOI: 10.1016/j.jcis.2021.04.079] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Revised: 04/13/2021] [Accepted: 04/16/2021] [Indexed: 12/01/2022]
Abstract
Highly transparent leafhopper (Thaia rubiginosa) wings are self-decorated with embroidered ball-shaped proteinaceous brochosmoes as distinct anti-predator defenses. The non-sticky brochosomal coating serves as antireflective structures for camouflage in vegetated environments. Inspired by the leafhopper wings, this study reports a new type of reversible antireflection coating enabled by integrating self-assembly methodologies using a shape memory polymer. The resulting embroidered ball-like structure array establishes a refractive index transition on surface, and thereby behaves omnidirectional antireflective characteristics in a broadband visible light region. Interestingly, the highly transparent appearance can be instantly erased and recovered by submerging in common liquids, such as water and ethanol, or by applying contact pressures at ambient conditions. Furthermore, the reversibility and structure-shape effect on the antireflective characteristics are systematically evaluated in this study.
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Affiliation(s)
- Pei-Chun Li
- Department of Chemical Engineering, National Chung Hsing University, 145 Xingda Road, Taichung City 40227, Taiwan
| | - Huei-Yin Chen
- Department of Chemical Engineering, National Chung Hsing University, 145 Xingda Road, Taichung City 40227, Taiwan
| | - Kuan-Ting Chiang
- Department of Chemical Engineering, National Chung Hsing University, 145 Xingda Road, Taichung City 40227, Taiwan
| | - Hongta Yang
- Department of Chemical Engineering, National Chung Hsing University, 145 Xingda Road, Taichung City 40227, Taiwan.
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Bang K, Jo Y, Chae M, Lee B. LensIet VR: Thin, Flat and Wide-FOV Virtual Reality Display Using Fresnel Lens and LensIet Array. IEEE TRANSACTIONS ON VISUALIZATION AND COMPUTER GRAPHICS 2021; 27:2545-2554. [PMID: 33755568 DOI: 10.1109/tvcg.2021.3067758] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
We propose a new thin and flat virtual reality (VR) display design using a Fresnel lenslet array, a Fresnel lens, and a polarization-based optical folding technique. The proposed optical system has a wide field of view (FOV) of 102°x102°, a wide eye-box of 8.8 mm, and an ergonomic eye-relief of 20 mm. Simultaneously, only 3.3 mm of physical distance is required between the display panel and the lens, so that the integrated VR display can have a compact form factor like sunglasses. Moreover, since all lenslet of the lenslet array is designed to operate under on-axis condition with low aberration, the discontinuous pupil swim distortion between the lenslets is hardly observed. In addition, all on-axis lenslets can be designed identically, reducing production cost, and even off-the-shelf Fresnel optics can be used. In this paper, we introduce how we design system parameters and analyze system performance. Finally, we demonstrate two prototypes and experimentally verify that the proposed VR display system has the expected performance while having a glasses-like form factor.
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17
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Gao LS, Cai QY, Hu ET, Zhou J, Li YP, Luo HH, Liu BJ, Zheng YX, Liu DQ. Double-sided optical coating of strongly curved glass by atomic layer deposition. OPTICS EXPRESS 2021; 29:13815-13828. [PMID: 33985110 DOI: 10.1364/oe.423085] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Accepted: 04/14/2021] [Indexed: 06/12/2023]
Abstract
A reaction chamber of atomic layer deposition (ALD) was developed for simultaneous coating on the inner and outer surfaces of a large-size and strongly curved glass bowl. The inner surface ALD process was in a showerhead reaction mode and the outer surface ALD process was in a cross-flow reaction mode. Blue reflection (BR) film of 400 nm wavelength and broadband antireflection (BBAR) film of 400-700 nm wavelength were coated on different glass bowls by ALD. The spectral uniformity of both coated bowls was studied. The measured spectra at multiple positions of the glass bowl with the BBAR coating show better spectral uniformity along the circumference than the depth. The spectral deviation is mainly caused by the non-uniformity of the film on the outer surface (<±3%), and the film on the inner surface has good uniformity along both the circumference and the depth (<±0.7%). The growth rate of the outer film was reduced by 10% on average compared to that of the inner film due to the different gas flow mode.
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Ghazaryan L, Handa S, Schmitt P, Beladiya V, Roddatis V, Tünnermann A, Szeghalmi A. Structural, optical, and mechanical properties of TiO 2 nanolaminates. NANOTECHNOLOGY 2021; 32:095709. [PMID: 33207326 DOI: 10.1088/1361-6528/abcbc1] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
The structural, optical, and mechanical properties of TiO2 nanolaminate films grown by plasma-enhanced atomic layer deposition are discussed. Several TiO2/Al2O3 and TiO2/SiO2 compositions have been investigated to study the effect of the relative number of ALD oxide cycles on the film properties to obtain a high refractive index coating with low optical losses, low roughness, and low mechanical stress. The formation of crystalline TiO2 observed at high deposition temperature, or film thickness was inhibited by periodically introducing ultra-thin amorphous layers into the film. Only 4 ALD cycles of Al2O3 (corresponding to ca. 0.5 nm) between 335 ALD cycles of TiO2 (ca. 11 nm) form a closed, distinct layer suppressing the crystallization in TiO2 film. Consequently, the roughness of the pure TiO2 film is reduced from ca. 20 nm rms to 1 nm rms in the 335/4 nanolaminate, with only a slight decrease of the refractive index from 2.46 to 2.44 in 100 nm pure TiO2 and the nanolaminate, respectively. The refractive indices of the nanolaminates in various compositions vary between 2.38 and 2.50 at 632 nm, and the corresponding optical losses from the films are low. The mechanical stress was reduced to about 140 MPa in several TiO2/Al2O3 nanolaminates; however, lower mechanical stress has not been obtained with the studied compositions. The nanolaminate structure is preserved up to 600 °C annealing temperature. After annealing at 800 °C, the individual layers interdiffuse into each other so that no distinct nanolaminate structure is detected. By using TiO2/Al2O3 nanolaminates with reduced mechanical stress, a narrow bandpass filter was realized on various substrates, including half-ball and aspherical lenses.
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Affiliation(s)
- Lilit Ghazaryan
- Institute of Applied Physics, Abbe Center of Photonics, Friedrich Schiller University Jena, Germany
| | - Shiti Handa
- Institute of Applied Physics, Abbe Center of Photonics, Friedrich Schiller University Jena, Germany
| | - Paul Schmitt
- Institute of Applied Physics, Abbe Center of Photonics, Friedrich Schiller University Jena, Germany
- Fraunhofer Institute for Applied Optics and Precision Engineering IOF, Jena, Germany
| | - Vivek Beladiya
- Institute of Applied Physics, Abbe Center of Photonics, Friedrich Schiller University Jena, Germany
| | | | - Andreas Tünnermann
- Institute of Applied Physics, Abbe Center of Photonics, Friedrich Schiller University Jena, Germany
- Fraunhofer Institute for Applied Optics and Precision Engineering IOF, Jena, Germany
| | - Adriana Szeghalmi
- Institute of Applied Physics, Abbe Center of Photonics, Friedrich Schiller University Jena, Germany
- Fraunhofer Institute for Applied Optics and Precision Engineering IOF, Jena, Germany
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Sun X, Tu J, Li L, Zhang W, Hu K. Preparation of wide-angle and abrasion-resistant multi-layer antireflective coatings by MgF2 and SiO2 mixed sol. Colloids Surf A Physicochem Eng Asp 2020. [DOI: 10.1016/j.colsurfa.2020.125106] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Franz M, Junghans R, Schmitt P, Szeghalmi A, Schulz SE. Wafer-level integration of self-aligned high aspect ratio silicon 3D structures using the MACE method with Au, Pd, Pt, Cu, and Ir. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2020; 11:1439-1449. [PMID: 33029473 PMCID: PMC7522463 DOI: 10.3762/bjnano.11.128] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 08/14/2020] [Indexed: 06/11/2023]
Abstract
The wafer-level integration of high aspect ratio silicon nanostructures is an essential part of the fabrication of nanodevices. Metal-assisted chemical etching (MACE) is a promising low-cost and high-volume technique for the generation of vertically aligned silicon nanowires. Noble metal nanoparticles were used to locally etch the silicon substrate. This work demonstrates a bottom-up self-assembly approach for noble metal nanoparticle formation and the subsequent silicon wet etching. The macroscopic wafer patterning has been done by using a poly(methyl methacrylate) masking layer. Different metals (Au, Pt, Pd, Cu, and Ir) were investigated to derive a set of technologies as platform for specific applications. Especially, the shape of the 3D structures and the resulting reflectance have been investigated. The Si nanostructures fabricated using Au nanoparticles show a perfect light absorption with a reflectance below 0.3%. The demonstrated technology can be integrated into common fabrication processes for microelectromechanical systems.
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Affiliation(s)
- Mathias Franz
- Nano Device Technologies, Fraunhofer Institute for Electronic Nano Systems ENAS, Technologie-Campus 3, 09126 Chemnitz, Germany
| | - Romy Junghans
- Nano Device Technologies, Fraunhofer Institute for Electronic Nano Systems ENAS, Technologie-Campus 3, 09126 Chemnitz, Germany
| | - Paul Schmitt
- Fraunhofer Institute for Applied Optics and Precision Engineering IOF, Center of Excellence in Photonics, Albert-Einstein-Straße 7, 07745 Jena, Germany
- Institute of Applied Physics, Friedrich-Schiller-University Jena, Albert-Einstein-Straße 15, 07745 Jena, Germany
| | - Adriana Szeghalmi
- Fraunhofer Institute for Applied Optics and Precision Engineering IOF, Center of Excellence in Photonics, Albert-Einstein-Straße 7, 07745 Jena, Germany
- Institute of Applied Physics, Friedrich-Schiller-University Jena, Albert-Einstein-Straße 15, 07745 Jena, Germany
| | - Stefan E Schulz
- Nano Device Technologies, Fraunhofer Institute for Electronic Nano Systems ENAS, Technologie-Campus 3, 09126 Chemnitz, Germany
- Center for Microtechnologies, Chemnitz University of Technology, Straße der Nationen 62, 09111 Chemnitz, Germany
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Schulz U, Gratzke N, Wolleb S, Scheinpflug F, Rickelt F, Seifert T, Munzert P. Ultraviolet-transparent low-index layers for antireflective coatings. APPLIED OPTICS 2020; 59:A58-A62. [PMID: 32225354 DOI: 10.1364/ao.59.000a58] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Accepted: 11/04/2019] [Indexed: 06/10/2023]
Abstract
Nanostructured low-index layers are useful as the last layers of antireflective (AR) coatings because they can broaden their spectral ranges and improve the performance for oblique light incidence. Structuring of evaporated organic layers by plasma opens a route to produce inorganic interference stacks and low-index layers in the same vacuum process. The organic material uracil has been investigated as a template material for AR nanostructures. An additional plasma-treatment step was added to the manufacturing process, which decreases the organic fraction of the coating substantially. As a result, a better environmental stability and higher transmission in the ultraviolet range was achieved.
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Dickey E, Niiranen K, Danforth B, Barrow WA. Macro-conformality of coatings deposited using high-speed spatial plasma-enhanced atomic layer deposition. APPLIED OPTICS 2020; 59:A16-A19. [PMID: 32225347 DOI: 10.1364/ao.59.000a16] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Accepted: 10/31/2019] [Indexed: 06/10/2023]
Abstract
Rotational spatial plasma-enhanced atomic layer deposition has been used to deposit thin films on half-sphere lenses. Non-uniformity of less than ±1% is demonstrated for Nb2O5 deposited at 1.4 Å/s and for SiO2 deposited at 6 Å/s.
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Beladiya V, Becker M, Faraz T, Kessels WMME, Schenk P, Otto F, Fritz T, Gruenewald M, Helbing C, Jandt KD, Tünnermann A, Sierka M, Szeghalmi A. Effect of an electric field during the deposition of silicon dioxide thin films by plasma enhanced atomic layer deposition: an experimental and computational study. NANOSCALE 2020; 12:2089-2102. [PMID: 31912855 DOI: 10.1039/c9nr07202k] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The growth, chemical, structural, mechanical, and optical properties of oxide thin films deposited by plasma enhanced atomic layer deposition (PEALD) are strongly influenced by the average-bias voltage applied during the reaction step of surface functional groups with oxygen plasma species. Here, this effect is investigated thoroughly for SiO2 deposited in two different PEALD tools at average-bias voltages up to -300 V. Already at a very low average-bias voltage (< -10 V), the SiO2 films have significantly lower water content than films grown without biasing together with the formation of denser films having a higher refractive index and nearly stoichiometric composition. Substrate biasing during PEALD also enables control of mechanical stress. The experimental findings are supported by density functional theory and atomistic simulations. They demonstrate that the application of an electric field during the plasma step results in an increased energy transfer between energetic ions and the surface, directly influencing relevant surface reactions. Applying an electric field during the PEALD process leads to SiO2 thin films with significantly improved properties comparable to films grown by ion beam sputtering.
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Affiliation(s)
- Vivek Beladiya
- Institute of Applied Physics, Friedrich Schiller University Jena, Albert-Einstein-Str. 15, 07745 Jena, Germany
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Abstract
Antireflection coatings (ARC) are essential for various optical components including such made of plastics for high volume applications. However, precision coatings on plastics are rather challenging due to typically low adhesion of the coating to the substrate. In this work, optimization of the atomic layer deposition (ALD) processes towards conformal optical thin films of Al2O3, TiO2 and SiO2 on poly(methyl methacrylate) (PMMA) has been carried out and a five-layer ARC is demonstrated. While the uncoated PMMA substrates have a reflectance of nearly 8% in the visible (VIS) spectral range, this is reduced below 1.2% for the spectral range of 420–670 nm by applying a double-side ARC. The total average reflectance is 0.7%. The optimized ALD coatings show a good adhesion to the PMMA substrates even after the climate test. Microscopic analysis on the cross-hatch areas on PMMA after the climate test indicates very good environmental stability of the ALD coatings. These results enable a possible route by ALD to deposit uniform, crack free, adhesive and environmentally durable thin film layers on sensitive thermoplastics like PMMA.
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Atomistic Simulations of Plasma-Enhanced Atomic Layer Deposition. MATERIALS 2019; 12:ma12162605. [PMID: 31443331 PMCID: PMC6719897 DOI: 10.3390/ma12162605] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Revised: 08/07/2019] [Accepted: 08/12/2019] [Indexed: 11/17/2022]
Abstract
Plasma-enhanced atomic layer deposition (PEALD) is a widely used, powerful layer-by-layer coating technology. Here, we present an atomistic simulation scheme for PEALD processes, combining the Monte Carlo deposition algorithm and structure relaxation using molecular dynamics. In contrast to previous implementations, our approach employs a real, atomistic model of the precursor. This allows us to account for steric hindrance and overlap restrictions at the surface corresponding to the real precursor deposition step. In addition, our scheme takes various process parameters into account, employing predefined probabilities for precursor products at each Monte Carlo deposition step. The new simulation protocol was applied to investigate PEALD synthesis of SiO2 thin films using the bis-diethylaminosilane precursor. It revealed that increasing the probability for precursor binding to one surface oxygen atom favors amorphous layer growth, a large number of –OH impurities, and the formation of voids. In contrast, a higher probability for precursor binding to two surface oxygen atoms leads to dense SiO2 film growth and a reduction of –OH impurities. Increasing the probability for the formation of doubly bonded precursor sites is therefore the key factor for the formation of dense SiO2 PEALD thin films with reduced amounts of voids and –OH impurities.
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