Recent Advances in Electrolytes for Potassium-Ion Batteries

Potassium-ion batteries (KIBs) are considered as the potential energy storage devices due to the abundant reserves and low cost of potassium. In the past decade, research on KIBs has generally focused on electrode materials. However, since electrolytes also play a key role in determining the cell performance, this review summarizes recent advances in KIB electrolytes and design strategies. Specifically, the review includes five parts. First, the organic liquid electrolyte is the most widely used type for KIBs. Its two major components, salts and solvents, have a huge impact on the formation of the solid electrolyte interphase and the performance of KIBs. Changes in salts/solvents, the introduction of additives, and the concentration increase all have a positive effect on organic liquid electrolytes. Second, the design of water-in-salt electrolytes can effectively widen the narrow electrochemical stability window of aqueous electrolytes. Third, despite the appealing properties, the ionic liquid electrolytes have not been widely applied due to its high cost. Fourth, the solid-state electrolytes have drawn much attention due to high safety, and current research has been working on improving their ionic conductivity at room temperature. Lastly, perspectives are provided to support the future development of suitable electrolytes for high-performance KIBs.     

1064nm准连续激光除漆研究

激光清洗作为环保节能的绿色清洗方法,在钢铁材料表面除漆领域具有重要的应用前景。利用波长为1064nm,重复频率为0.5～50kHz可调的声光调Q准连续Nd:YAG激光对钢基底表面漆层样品进行了清洗实验和工作机理研究。模拟和实验结果表明,在钢基底表面漆层脉冲激光去除中,阈值清洗条件下有效清洗机理是振动效应,而有基底损伤时有效清洗机理是振动效应和烧蚀效应;对于厚为50μm漆层的钢铁基底,在平均功率20W以上且搭接率为80%时,能够完全清除基板表面油漆而不损伤其基体。在保证激光功率密度和扫描搭接率适当的同时,通过提高激光器输出功率、脉冲重复频率或增加光斑直径,可以获得更好的清洗效果和更高的清洗效率。     

非离子表面活性剂在阻挡层CMP后清洗中去除颗粒作用的研究

本文对非离子表面活性剂在阻挡层CMP后清洗中对颗粒的去除作用进行了研究。实验过程中,通过改变活性剂的浓度,在12inch多层铜布线片上进行了一系列的实验来确定最佳的清洗效果。然后对活性剂在缺陷控制、颗粒去除,以及活性剂在清洗过程中所起的负面作用等方面进行了讨论。实验结果表明,非离子表面活性剂在阻挡层CMP后清洗中根据浓度的不同所起的正面、负面作用不同,从而为阻挡层CMP后清洗过程中非离子表面活性剂的加入起到一定的指导作用。     

基于原子力显微镜的胶体颗粒相互作用力测量研究

胶体颗粒絮凝是环境科学领域的研究热点之一,不同环境条件下颗粒间的相互作用力对絮凝起着重要作用.采用聚苯乙烯胶体颗粒作为研究对象,设计实验方案,用原子力显微镜(atomic force microscope,AFM)测量不同电解质溶液中颗粒间相互作用力.在一定范围内,实验值和扩展的胶体稳定性(XDLVO)理论值吻合.液相环境中测量聚苯乙烯胶体颗粒间相互作用力的技术为测量具有复杂形状的胶体颗粒间相互作用力提供了依据.     

The removal of nanoparticles from sub-micron trenches using megasonics

The removal of nanoparticles form patterned wafers is one of the main challenges facing the semiconductor industry. In this paper, the removal of 100 and 200 nm polystyrene latex (PSL) particles from silicon trenches was investigated. Red fluorescent PSL particles were utilized in the cleaning experiments and were counted using fluorescent microscopy. All the experiments were conducted in a single wafer megasonic tank using deionized water (DI). Trenches were fabricated with widths varying from 200 nm to 2 μm and with an aspect ratio of one. Results show that removal of particles from larger trenches is faster compared to smaller trenches and that megasonics power is more important in the removal process than cleaning time.     

GLSI多层铜布线CMP后BTA去除研究

本文通过静态腐蚀速率的方法分析确立了碱性清洗剂中FA/OⅡ型螯合剂和FA/OⅠ型表面活性剂对BTA的去除规律。通过单因素实验和复合清洗剂的实验优化,确定了去除BTA的清洗剂配方,并通过接触角实验进一步证实实验结果的有效性。最后,将优化后的清洗剂配方在实际生产线上做试验,结果表明能有效去除BTA、CuO晶粒及磨料SiO2,且基本无界面腐蚀。解决了一直难以解决的多层铜布线CMP后有效去除BTA的难题,且该清洗剂成分简单,成本低而且环保。     

An efficient wet-cleaning of SiGe virtual substrates and of thick, pure Ge layers on Si(0 0 1) after a chemical mechanical planarization step

The aim of this study is to propose an efficient wet cleaning of the surfaces of the SiGe virtual substrates just after a chemical mechanical polishing step. We have first of all studied the chemical compatibility of miscellaneous solutions, such as the standard cleaning 1 (SC1), the Standard Cleaning 2 (SC2), the CARO one etc with SiGe. A definite, logarithmic-like increase of the etch rate with the Ge content has been obtained for the SC1, the SC2 and the CARO solutions (with values 1000-10,000 those of Si evidenced for pure Ge), making them unsuitable for Ge contents above 30%. We have thus investigated the efficiency of new cleaning sequences (named “DDC-SiGe” for SiGe and “HF/O₃” for pure Ge) that call upon diluted HF and ozone solutions spiked with HCl, on SiGe and pure Ge. The overall material consumption of those cleaning sequences, which increases from 10 Å for pure Si up to 130 Å for pure Ge, is quite low. The particle removal efficiency of such cleanings is around 99% for Si_0.8Ge_0.2 and Si_0.7Ge_0.3. It drops down to 83% for Si_0.5Ge_0.5 and to 65% for pure Ge. This is most probably due to pre-existing epitaxy defects which are revealed during the wet cleaning then wrongly assimilated to particles by our surface inspection tool. The metallic contaminants present on the surface after the use of our wet cleaning sequences have a surface density lower than 10¹⁰ atoms cm⁻², this whatever the Ge content of the underlying layer.     

Comparison of novel cleaning solutions with various chelatingagents for post-CMP cleaning on poly-Si film

In this study, various cleaning solutions containing chelating agents with carboxyl acid group (-COOH), such as ethylenediaminetetraacetic acid, citric acid and oxalic acid, were developed for post-poly-Si CMP cleaning. The chelating agent and tetramethylammonium hydroxide (TMAH) were simultaneously added into 2% ammonium hydroxide alkaline solution to promote the removal efficiency on particles and metallic impurities. The effectiveness of various cleaning recipes and their interaction mechanism with the poly-Si surface were studied. We could explain the surface behavior of various cleaning solutions by the different molecular size and charge of chelating agents. Based on the mechanism, the behavior of surface particle and metallic impurity can be realized. The co-existence of TMAH with citric acid or oxalic acid in the alkaline cleaning solutions can significantly enhance the electrical properties of capacitors     

激光等离子体冲击波清洗中的颗粒弹出移除

针对激光等离子体冲击波清洗颗粒技术中的滚动移除机制缺陷,提出一种基于颗粒弹性形变的弹出移除模型。从冲击波与颗粒相互作用出发,考虑冲击波波后气体分子与颗粒的碰撞,结合颗粒弹性储能机制,得到弹出所需要的最小弹性形变高度。根据颗粒弹出所需最低速度和冲击波基本关系式得到满足颗粒弹出要求的冲击波马赫数,结合冲击波波后压强分布特点给出了颗粒弹出所需的外部条件。清洗实验证实了颗粒弹出移除机制的正确性。     

窄间隙介质阻挡放电清除硅片表面颗粒污染物

硅片清洗技术已成为制备高技术电子产品的关键技术。采用窄间隙介质阻挡放电方法研制了低温氧等离子体源,把氧离解、电离、离解电离成O、O-、O+和O2(a1Δg)等低温氧等离子体,其中O-和O2(a1Δg)活性粒子进一步反应形成高质量浓度臭氧气体,再溶于酸性超净水中,用于去除硅片表面颗粒污染物。实验结果表明:当等离子体源输入功率为300 W时,臭氧气体质量浓度最高为316 mg/L;高质量浓度臭氧气体溶于pH值为3.8的超净水中形成臭氧超净水,质量浓度为62.4 mg/L;在硅片清洗槽内,高质量浓度臭氧超净水仅用30 s就可去除硅片表面的Cu、Fe、Ca、Ni和Ti等金属颗粒物,去除率分别为98.4%、95.2%、88.4%、85.2%和64.1%。本方法与目前普遍使用的RCA清洗法相比,具有无需大剂量化学试剂和多种液体化学品、清洗工艺简单、投资及运行成本低等优势。因此,窄间隙介质阻挡放电清洗硅片表面颗粒污染物技术具有广阔的市场应用前景。     

高比能水体系锂电池研究

实现水溶液锂电池的关键技术是如何保护金属锂电极不与水反应。提出了一种保护金属锂电极,其不仅在有机电解液体系稳定而且在水溶液中也可稳定工作,这种锂电极可以用于水体系锂电池。该研究制备了双层锂离子电解质保护的金属锂电极,其外层采用的LAGP（Li1＋x＋yAlxGe2-x SiyP3-yO12）玻璃陶瓷电解质相对于包括水溶液等电解液是稳定的,该玻璃陶瓷电解质的电导率达到0.57 mS cm^-1。通过交流阻抗评估发现不同电解质间的界面阻抗是水体系锂电池内阻的主要来源。最终采用双层保护金属锂电极制备的水体系锂空气电池和锂水电池可以稳定工作。     

玻璃表面微颗粒的激光清洗研究(特邀)

针对玻璃表面微颗粒的污染问题,文中研究了脉冲激光对颗粒污染物的清洗阈值和清洗效果。通过颗粒吸附和形变模型计算石英玻璃表面与颗粒间的吸附力,分析热应力与激光能量密度的关系。通过吸附力和热应力的对比分析得到颗粒污染物的清洗条件和理论阈值。实验对比石英玻璃表面颗粒的正面入射和反面入射的清洗效果,研究功率密度、扫描速度和清洗次数等参数对清洗率的影响。结果表明,大颗粒污染物的反面清洗可以完全去除,正面清洗小颗粒污染物的效果较好。单因素和三因素研究表明激光功率密度对清洗率的影响比扫描速度大,激光清洗次数对清洗率几乎没有影响。     

Particle removal from silicon wafer surface in wet cleaning process

Particle removal from silicon wafer surfaces was studied using acid and alkaline solutions employed in wet cleaning processes found in semiconductor manufacturing. It was demonstrated that alkaline solutions are superior to acid solutions in terms of particle removal efficiency. The following particle removal mechanism in the alkaline solutions was confirmed: the solutions etch the wafer surfaces to lift off particles, and the particles are then electrically repelled by the wafer surfaces. It was determined experimentally that an etch rate of 0.25 nm/min or more is required to lift off the particles adsorbed on the wafer surfaces. It was also confirmed that when the pH value of NH₄OH-H₂O₂-H₂O solution becomes higher, polystyrene latex spheres and natural organic particles are oxidized, with their surface turning into a gel and their shape changing. The particle removal efficiency was demonstrated to be degraded by the oxidation of organic particles. The results suggest that the mixing ratio of the NH₄OH-H₂O₂-H ₂O solution should be set at 0.05:1:5     

Effects of size, humidity, and aging on particle removal from Si wafers

The effects of particle size, humidity, and aging time on particle removal from silicon wafers were investigated with a laser shock wave at a constant removal force. Particle adhesion force, shock wave cleaning force, and the removal moment ratio were calculated and related to particle removal efficiency (PRE). The presence of capillary forces and particle deformation significantly increased the adhesion force. In order to control the humidity and magnitude of deformation, humidity and aging time were varied during particle removal tests. PRE decreased rapidly for particle sizes below 1 μm as the humidity and contact area increase. The calculations of removal moment ratios agreed well with the experimental observations. Both humidity and process time should be controlled to avoid the aging of particles and to achieve high PRE for particles smaller than 1 μm.     

利用激光清洗技术清除砂岩及光学元件表面污染物

激光清洗技术与其他清洗方法（化学清洗、超声波清洗等）相比,具有保证清洗对象无损、清洗效果好、精细和无污染等优点,正在被广泛地研究和应用。根据去除原理的不同,激光清洗技术被分类为干式激光清洗、湿式激光清洗和激光等离子体冲击波等方法。在文物保护领域中,石质文物表面的污染物影响文物美观,更严重威胁着文物的保存。在高功率固体激光装置中,光学元件表面的污染物严重影响了激光系统的正常运行。利用激光清洗技术清除砂岩表面的墨迹污染物以及镀金K9玻璃表面颗粒和油脂污染物,利用显微镜、暗场成像法、紫外可见近红外分光光度计、X射线光电子能谱仪等方式检测清洗效果,结果表明清洗效果良好。     

A new cleaning process combining non-ionic surfactant with diamond film electrochemical oxidation for polished silicon wafers

This paper presents a new cleaning process for particle and organic contaminants on polished silicon wafer surfaces.It combines a non-ionic surfactant with boron-doped diamond(BDD) film anode electrochemical oxidation. The non-ionic surfactant is used to remove particles on the polished wafer's surface,because it can form a protective film on the surface,which makes particles easy to remove.The effects of particle removal comparative experiments were observed by metallographic microscopy,which showed tha...     

非离子型表面活性剂结合金刚石膜电化学氧化的新型抛光后晶片清洗工艺

本文针对抛光后晶片的颗粒和有机污染物提出了一种新型清洗方法,它结合了非离子表面活性剂和掺硼金刚石膜（BDD）阳极电化学氧化的优势。非离子表面活性剂可以在抛光后晶片上形成一层保护膜,使晶片表面颗粒易于去除。颗粒去除对比实验结果通过金相显微镜观察得知,体积比为1%的非离子表面活性剂的颗粒去除效果最佳。然而表面活性剂保护膜本身属于有机物,它最终也需要被去除。金刚石膜阳极电化学氧化（BDD-EO）可以用来去除有机物,因为它可以有效降解有机物。三个有机污染物去除对比实验分别为：一是先用非离子表面活性剂再用BDD-EO,二是单纯用BDD-EO去除有机物,第三种是用传统RCA清洗技术。通过XPS检测结果表明,用BDD-EO清洗的晶片表面的有机残留明显少于传统RCA技术,并且晶片表面的非离子表面活性剂也可以有效去除。     

Particle deposition and removal in wet cleaning processes for ULSImanufacturing

Particle deposition on wafer surfaces in solutions can be described by the well-documented principles of colloid science. Particle concentration, solution pH, and ionic strength in solutions are all important factors which determine the number of particles which deposit on wafer surfaces immersed in liquids. maximum particle deposition is observed in high ionic strength acidic solutions and is reduced as solution pH increase. Particle removal efficiencies in various solutions were also investigated; NH₄OH-H₂O₂-H ₂O solutions were optimized in NH₄OH content around the ratio of 0.05:1.15 (0.05 part NH₄OH, 1 part H₂O₂, 5 parts H₂O). Wafer damage as measured by surface micro-roughness was not increased during NH₄ OH-H₂O₂-H₂O treatment using this ratio     

Osmotic Power Generation with Positively and Negatively Charged 2D Nanofluidic Membrane Pairs

In nature, hierarchically assembled nanoscale ionic conductors, such as ion channels and ion pumps, become the structural and functional basis of bioelectric phenomena. Recently, ion‐channel‐mimetic nanofluidic systems have been built into reconstructed 2D nanomaterials for energy conversion and storage as effective as the electrogenic cells. Here, a 2D‐material‐based nanofluidic reverse electrodialysis system, containing cascading lamellar nanochannels in oppositely charged graphene oxide membrane (GOM) pairs, is reported for efficient osmotic energy conversion. Through preassembly modification, the surface charge polarity of the 2D nanochannels can be efficiently tuned from negative (?123 mC m^?2) to positive (+147 mC m^?2), yielding strongly cation‐ or anion‐selective GOMs. The complementary two‐way ion diffusion leads to an efficient charge separation process, creating superposed electrochemical potential difference and ionic flux. An output power density of 0.77 W m^?2 is achieved by controlled mixing concentrated (0.5 m ) and diluted ionic solutions (0.01 m ), which is about 54% higher than using commercial ion exchange membranes. Tandem alternating GOM pairs produce high voltage up to 2.7 V to power electronic devices. Besides simple salt solutions, various complex electrolyte solutions can be used as energy sources. These findings provide insights to construct cascading nanofluidic circuits for energy, environmental, and healthcare applications.