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101.
硼离子选择注入制备多孔硅微阵列   总被引:1,自引:0,他引:1  
根据 p型硅和 n型硅不同的制备多孔硅的工艺条件 ,利用硼离子选择注入 ,在 n型硅片上的局部微区域 ,形成易于腐蚀的 p型硅 ,用电化学腐蚀方法制备出图形化的多孔硅阵列 .省去了传统掩膜腐蚀工艺的掩膜材料的选取与制备以及后道工艺中掩膜材料的清除等工艺 ,克服了掩膜材料掩蔽效果较差以及存在横向钻蚀等缺点 .通过 AFM,SEM测试 ,证明该方法的效果很好  相似文献   
102.
文章简述了光电印制电路板中聚合物光波导层的制作应该遵循的原则,介绍了光波导层的主要成型工艺,包括反应离子蚀刻、平版影印、激光烧蚀和加热模压等方法。  相似文献   
103.
对TFT器件工艺中的反应性离子刻蚀技术进行了研究,给出了TFT器件工艺中常见薄膜刻蚀速率的实验结果,并讨论了掺杂气体(如H2、Ar等)对刻蚀速率的影响。  相似文献   
104.
国内正在崛起的新型电池   总被引:2,自引:0,他引:2  
我国电池产量居世界首位, 但其中产量的90% 以上为低档次电池。近10多年来, 我国新型电池的生产引人注目。其中有碱性锌锰电池、锂一次电池及小型可充电镉镍电池、氢镍电池和锂离子电池。介绍了国内正在崛起的几种新型电池。  相似文献   
105.
该文阐述了改善PCB镀铜均镀性的基本方法。  相似文献   
106.
This paper presents two new approaches used in the secondary ion mass spectrometry (SIMS) for high sensitivity dopant and impurity analysis in HgCdTe materials, namely, the high mass resolution with dynamic transfer and the MCs+ technique. It is shown that better detection limits for As and Cu can be obtained at a level of 2–5e14 at/cm3. The MCs+ technique has added advantages of better measurement precision, monitoring Cd composition in the same profile, and small device area analysis capability. Advantages and trade-offs of each technique are discussed and compared. An updated detection limit table for all elements measured in HgCdTe materials using SIMS is also presented.  相似文献   
107.
This report focuses on research into waveguides prepared by K+-Na+ ion exchange with the help of an electric field, and the subsequent comparison with waveguides prepared by pure thermal ion exchange. The goals of this work were to determine the characteristics of and to address the technological problems associated with waveguides prepared in two types of highly pure optical glass: special soda-lime silica GIL49 glass produced from pure raw materials and commercially prepared borosilicate BK7 glass. An appropriate chemical mixture, KNO3:Ca(NO3)2 in the molar ratio of 41:59, was used as the source of potassium ions. Experiments were conducted at temperatures between 250 and 410°C, and electric field values between 0 and 150 V/mm. The number of modes, depth, profile, and the change in refractive index (Δn) were measured for samples from each type of glass under various technological conditions. All of these parameters can be controlled accurately and repeatedly by the electric field. These experiments have also shown that a particular advantage of these types of pure glass is the low waveguide optical losses (0.1 to 0.2 dB/cm) attainable.  相似文献   
108.
One of the most effective methods to achieve high-performance perovskite solar cells (PSCs) is to employ additives as crystallization agents or to passivate defects. Tri-iodide ion has been known as an efficient additive to improve the crystallinity, grain size, and morphology of perovskite films. However, the generation and control of this tri-iodide ion are challenging. Herein, an efficient method to produce tri-iodide ion in a precursor solution using a photoassisted process for application in PSCs is developed. Results suggest that the tri-iodide ion can be synthesized rapidly when formamidinium iodide (FAI) dissolved isopropyl alcohol (IPA) solution is exposed to LED light. Specifically, the photoassisted FAI–IPA solution facilitates the formation of fine perovskite films with high crystallinity, large grain size, and low trap density, thereby improving the device performance up to 22%. This study demonstrates that the photoassisted process in FAI dissolved IPA solution can be an alternative strategy to fabricate highly efficient PSCs with significantly reduced processing times.  相似文献   
109.
Diverse touch experiences offer a path toward greater human–machine interaction, which is essential for the development of haptic technology. Recent advances in triboelectricity-based touch sensors provide great advantages in terms of cost, simplicity of design, and use of a broader range of materials. Since performance solely relies on the level of contact electrification between materials, triboelectricity-based touch sensors cannot effectively be used to measure the extent of deformation of materials under a given mechanical force. Here, an ion-doped gelatin hydrogel (IGH)-based touch sensor is reported to identify not only contact with an object but also deformation under a certain level of force. Switchable ionic polarization of the gelatin hydrogel is found to be instrumental in allowing for different sensing mechanisms when it is contacted and deformed. The results show that ionic polarization relies on conductivity of the hydrogels. Quantitative studies using voltage sweeps demonstrate that higher ion mobility and shorter Debye length serve to improve the performance of the mechanical stimuli-perceptible sensor. It is successfully demonstrated that this sensor offers dynamic deformation-responsive signals that can be used to control the motion of a miniature car. This study broadens the potential applications for ionic hydrogel-based sensors in a human–machine communication system.  相似文献   
110.
Alloy anodes composed of microsized particles receive increasing attention recently, which outperform the nanostructured counterparts in both the manufacturing cost and volumetric energy density. However, the pulverization of particles and fracture of solid electrolyte interphase (SEI) during cycling brings about fast capacity degradation. Herein, it is shown how normally considered fragile SEI can become highly elastic through electrolyte chemistry regulation. Compared to the SEI constructed in classic carbonate electrolyte, the atomic force microscopy tests reveal that the one built in ether-based electrolyte doubles the maximum elastic strain to accommodate the repeated swelling-contracting. Such an SEI effectively encapsulates the microsized Sb anodes to prevent the capacity loss from particle isolation. Coupled with an intercalation-assisted alloying reaction mechanism, a sustained capacity of ≈573 mAh g−1 after 180 cycles at 0.1 A g−1 with outstanding initial Coulombic efficiency is obtained, which is among the highest values achieved in K-ion batteries. This study emphasizes the significance of building robust SEI, which offers the opportunity to enable stable microsized alloy anodes.  相似文献   
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