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In order to break through the structural limitation of 2D planar film and develop getter with large specific surface area (SSA), the 3D Ni-nanoarray based Ti–Zr–V film getter was prepared to effectively increase the SSA and finally improve its adsorption performance. The morphology and adsorption performance of Ti–Zr–V films deposited on Ni-based nano-scaffold and silicon substrate were studied by scanning electron microscopy, thermogravimetric analysis and hydrogen adsorption test. The gettering properties are found to be directly dependent on the deposited thickness of Ti–Zr–V film. The results show that the 80-nm-thick Ti–Zr–V film can maintain the porous structure of the original Ni nanoarrays and has the largest adsorption rate (1.274 × 10−2 mg/(s·g)) and adsorption capacity (0.0587 mg) in the thermogravimetric analysis experiment. Under the same preparation and activation conditions, the H2 adsorption rate and adsorption capacity of 3D Ni-nanoarray based Ti–Zr–V film are about three times and twice that of Ti–Zr–V film on silicon substrate, respectively. This is because the increase in SSA promotes the gas adsorption on the getter surface. The study indicates that the application of porous nanoarray as scaffold for getter film is an effective way to improve the adsorption performance. Introduction Non evaporating getter (NEG) is widely used in vacuum packaging of micro-electro-mechanical systems (MEMS) devices because of its small volume, fast pumping speed [1], repeated activation and no pollution to devices [2,3]. With the further miniaturization of MEMS devices and the diversification of application environment, it is imperative to significantly improve the gas adsorption capacity of getter [4]. The continuous optimization of adsorption performance of getter fundamentally depends on its structural and morphological characteristics. High specific surface area (SSA) and large porosity is conducive to improve the adsorption rate and adsorption capacity of getter in limited space [5]. According to the preparation process, NEG can be mainly divided into three categories: pressing type, porous sintered type and thin film type [6]. Thin-film NEG is the most applicable to MEMS devices because of its small volume, high adsorption rate [7] and low activation temperature [[8], [9], [10]]. By optimizing the deposition technology, the structural morphology of thin-film NEG has been developed from granular dense layer to open porous column [11], and the gettering performance has been significantly optimized. In order to further improve the adsorption property of thin-film NEG, researchers have designed multilayer getter films based on the characteristics of different getter materials [12]. For example, adding surface protective layer [13,14], adding barrier layer or adjusted layer between getter and substrate [15], inserting temperature control layer [16] and so on. To a certain extent, the above methods help solve the surface oxidation of getter film and the poison by the outgassing of substrate. However, since the getter films prepared by these methods are still two-dimensional, it is difficult to obtain remarkable increase in specific surface area, which restricts the improvement of adsorption performance. In order to break through the structural limitation of two-dimensional planar film and develop getters with large SSA and high porosity, the three-dimensional (3D) getter with nano fine structure has been explored and studied [17]. Chen et al. [18] deposited Ti film on the vertical carbon nanotube. Owing to the high space utilization brought by the vertical array structure, the SSA of the getter film was increased and the adsorption rate was greatly improved. Boyko et al. [19] prepared Ti–V getter on 3D porous silicon nanostructures with large SSA of about 167 m2/cm3. Recently, Wang et al. [20] deposited Ti–Zr–V-Hf film on the open-cell copper metal foam substrate with wave-like microstructure. The film surface showed island-like structure and macropores, which effectively improved the pumping ability. Some shortages of these work are that the influence of getter film thickness on sorption performance has not receive much consideration and they lack the accurate measurements of getter dynamic sorption performance under vacuum. Although there are few related studies till now, remarkable achievements have been made in the research of three-dimensional nano getters with large SSA and high porosity. Ni nanoarray has the a lot of advantages, for example, simple preparation process, adjustable structure size of nano units, low cost and large SSA and so on. Therefore, Ni nanoarray can be used as a good scaffold for the preparation of new 3D getter. In this study, we proposed and prepared Ni nano scaffolds with large SSA, and coated Ti–Zr–V film on its surface to prepare a new-type getter. Thermogravimetric analysis (TGA) and hydrogen adsorption test in vacuum system show that the adsorption performance of 3D Ni-nanoarray based Ti–Zr–V film is better than that of two-dimensional getter film on silicon wafer. Section snippets Preparation of Ni nanoarrays The Ni nano-conical arrays with large SSA were prepared by electrodeposition. The electrodeposition anode was a nickel sheet with purity of 99.9%, thickness of 1 mm and size of 20 mm × 40 mm. The cathode was commercial copper sheet with purity of 99.9%, thickness of 0.3 mm and size of 20 mm × 40 mm. The main components of the electrolyte were 1 mol/L NiCl2·6H2O, 0.5 mol/L H3BO3 and 4 mol/L NH4Cl. The pH value of the electroplating solution was adjusted to 4.0 before electrodeposition, and the Preparation and morphology characterization of Ni-nanoarray based Ti–Zr–V film A new-type 3D getter was prepared by depositing Ti–Zr–V film on the prepared Ni nanoarrays by three target co-sputtering method from Ti, Zr and V targets. The deposition system was baked and degassed before coating to eliminate the effect of residual gas (such as water vapour) on the film quality. The background pressure of the deposition chamber before sputtering was 5 × 10−5 Pa and the working pressure during coating was 1 Pa with Ar as the working gas. The Ni nanoarrays grown under the Thermogravimetric analysis In order to investigate the adsorption behavior of the Ni-nanoarray based Ti–Zr–V film getter, thermogravimetric analysis tests were carried out in a TGA8000 analyzer. The heating and insulation process is as follows: 1) heating from room temperature to 100 °C with a heating rate of 15 °C/min, 2) keeping at 100 °C for 20 min, 3) heating to 400 °C with a heating rate of 15 °C/min, 4) keeping at 400 °C for 40 min, 5) heating to 500 °C with a heating rate of 10 °C/min, 6) keeping at 500 °C for Conclusion In this paper, a new-type NEG film was fabricated by coating Ti–Zr–V film on 3D Ni-nanoarrays. The effects of different preparation conditions on the morphology of Ni nanoarrays and the thickness of sputtering coated Ti–Zr–V film on the getter adsorption performance were studied. The results show that the 80-nm-thick Ti–Zr–V film can maintain the porous structure of the original Ni nanoarrays and has the largest adsorption rate (1.274 × 10−2 mg/(s·g)) and adsorption capacity in the Funding This work was supported by the National Natural Science Foundation of China ( 62101172 ), the Open Foundation of State Key Laboratory of Compressor Technology ( SKL-YSJ202003 ), Anhui Provincial Natural Science Foundation ( 2008085QE224 ), and the Fundamental Research Funds for the Central Universities ( JZ2022HGTB0241 , JZ2022HGTB0266 ). CRediT authorship contribution statement Qing Cao: Writing – review & editing, Supervision, Methodology. Xianyi Wang: Writing – original draft, Data curation. Sihui Wang: Resources. Bang Xiao: Formal analysis. Jun Wu: Resources. Shuyi Gan: Resources. Xudong Yuan: Supervision. Pengcheng Li: Validation, Supervision. Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. References (21) C.C. Li et al. Fabrication and characterization of non-evaporable porous getter films Surf. Coating. Technol. (2005) Y. Xu et al. Influence of deposition pressure, substrate temperature and substrate outgassing on sorption properties of Zr-Co-Ce getter films J. Alloys Compd. (2016) R. Širvinskaitė et al. Single metal zirconium non-evaporable getter coating Vacuum (2020) C. Benvenuti et al. Vacuum properties of TiZrV non-evaporable getter films Vacuum (2001) A.E. Prodromides et al. Lowering the activation temperature of TiZrV non-evaporable getter films Vacuum (2001) H. Yoshida Testing of non-evaporable getter pills for standardization of their pumping performance testing method Vacuum (2022) R. Bogue Recent developments in MEMS sensors: a review of applications, markets and technologies Sens. Rev. (2013) P. Yan et al. Latest development of non-evaporable getter material Chin. J. Vacuum Sci. Technol. (2018) D.T. Li et al. Applications of non evaporable getter pump in vacuum metrology Vacuum (2011) Z. Hou et al. A newly MEMS vacuum gauge with multi-modes for low vacuum measurement Vacuum (2021) There are more references available in the full text version of this article. Cited by (0) Recommended articles (0) View full text © 2022 Elsevier Ltd. All rights reserved. About ScienceDirect Remote access Shopping cart Advertise Contact and support Terms and conditions Privacy policy We use cookies to help provide and enhance our service and tailor content and ads. By continuing you agree to the use of cookies . Copyright © 2022 Elsevier B.V. or its licensors or contributors. ScienceDirect® is a registered trademark of Elsevier B.V. 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