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161.
静态电流(IDDQ)测试是一种很灵敏且具有成本效益的集成电路测试技术,针对0.13μm某种DSP芯片在量产初期所遇到的IDDQ测试失效情况,利用激光束诱导电阻值变化(OBIRCH)、电压对比(VC)、扫描电镜(SEM)和聚焦离子束(FIB)等电学与物理失效分析方法,确定由离子注入偏差所引起的MOS器件物理缺陷是造成IDDQ失效的原因,据此进行了离子注入光阻的工艺改进,最终实现了成品率的提升. 相似文献
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A device able to electrokinetically concentrate cationic samples has many potential medical and industrial applications, but until now has remained undeveloped due to the lack of a commercial anion-permselective material leading to a prohibitively complex fabrication procedure. Herein, a novel multiscale-porous anion exchange membrane (MP-AEM) that enables the convenient and scalable electrokinetic concentration of cationic species is proposed. A mechanically enhanced multiscale-porous structure with a solid framework is realized by adopting polyester resin as an additive to overcome the intrinsic limitations of the AEM material. The scalable MP-AEM-embedded electrokinetic concentrator is devised based on the peculiar properties of the MP-AEM that for allow both ion and fluid transport. With the MP-AEM, the concentrator is fabricated in a highly streamlined manner consisting only of a simple insertion and assembly. The concentration performance of the MP-AEM-embedded electrokinetic concentrator is demonstrated with a positively charged fluorescent dye and a fluorescein-labeled protein, and the results show enrichment factors of 250 and 500, respectively. The MP-AEM makes cationic electrokinetic concentration more accessible and scalable, thereby enabling further progress in a wide range of fields. 相似文献
164.
为了实现精确放疗过程中精确定位和肿瘤位置的精确测量,建立了基于双目视觉的医疗机器人摆位测量系统,并对系统所采用的摄像机标定方法、标记点识别及其三维坐标计算、摆位系统的位置验证等算法进行研究。建立基于双目视觉的医疗机器人摆位测量系统;提出了一种对摄像机采用基于平面棋盘格和立体标定模板相结合的摄像机标定新方法;采用Roberts梯度算子对图像分割的方法,识别标记点中心并计算其三维坐标;通过比较基于双目视觉计算和三维坐标测量仪器测量的各个标记点三维坐标的摆位误差,实现放疗过程中位置验证和精确摆位。实验结果表明:摄像机的标定精度为36.5×10-3 mm和各个标记点的三维坐标平均偏差为δX=0.573mm、δY=0.495mm、δZ=0.430mm,测量方法可获得较高的标定精度和摆位精度,能满足精确放疗对高精度摆位系统的临床需求。 相似文献
165.
Unusual Formation of ZnCo2O4 3D Hierarchical Twin Microspheres as a High‐Rate and Ultralong‐Life Lithium‐Ion Battery Anode Material 下载免费PDF全文
Jing Bai Xiaogang Li Guangzeng Liu Yitai Qian Shenglin Xiong 《Advanced functional materials》2014,24(20):3012-3020
A facile two‐step strategy involving a polyol method and subsequent thermal annealing treatment is successfully developed for the large‐scale preparation of ZnCo2O4 various hierarchical micro/nanostructures (twin mcrospheres and microcubes) without surfactant assistance. To the best of our knowledge, this is the first report on the synthesis of ZnCo2O4 mesoporous twin microspheres and microcubes. More significantly, based on the effect of the reaction time on the morphology evolution of the precursor, a brand‐new crystal growth mechanism, multistep splitting then in situ dissolution recrystallization accompanied by morphology and phase change, is first proposed to understand the formation of the 3D twin microshperes, providing new research opportunity for investigating the formation of novel micro/nanostructures. When evaluated as anode materials for lithium‐ion batteries (LIBs), ZnCo2O4 hierarchical microstructures exhibit superior capacity retention, excellent cycling stability at the 5 A g?1 rate for 2000 cycles. Surprisingly, the ZnCo2O4 twin microspheres show an exceptionally high rate capability up to the 10 A g?1 rate. It should be noted that such super‐high rate performance and cycling stability at such high charge/discharge rates are significantly higher than most work previously reported on ZnCo2O4 micro/nanostructures and ZnCo2O4‐based heterostructures. The ZnCo2O4 3D hierarchical micro/nanostructures demonstrate the great potential as negative electrode materials for high‐performance LIBs. 相似文献
166.
作为pn结成型的重要参数,离子注入温度对晶格缺陷和材料扩散的影响较大。在碲镉汞的离子注入过程中,注入温度很大程度上影响着注入区的尺寸与光刻掩膜的形貌。从离子注入工艺的温度控制出发,研究了该工艺中的束流、注入能量、接触面粗糙度等因素;结合器件的I-V曲线,探究了注入温度对碲镉汞红外探测器性能的影响。结果表明,较低的注入束流、冷却温度以及良好的导热面,可以保证实际注入温度低于光刻胶的耐受温度,从而提高工艺过程的成品率。同时,较低的注入温度对于减小暗电流及注入区扩散面积起到了一定的作用,提高了碲镉汞红外探测器光敏元的性能。 相似文献
167.
氧化物隔离等平面S(z)工艺采用全离子注入工艺代替原始的扩散工艺,使得整个工艺流程更为简化,对于浅结工艺的重复性和均匀性均有较大提高。发射极条和基极条形成自对准,发射极四周靠墙。发射极条宽为3微米时,f_γ>3GHz。该工艺已应用于超高速双极ECL分频器中。 相似文献
168.
Qiang Chen Hang Li Xuan Lou Jianli Zhang Guangya Hou Jun Lu Yiping Tang 《Advanced functional materials》2023,33(17):2214920
Aqueous ammonium ion hybrid supercapacitor (A-HSC) combines the charge storage mechanisms of surface adsorption and bulk intercalation, making it a low-cost, safe, and sustainable energy storage candidate. However, its development is hindered by the low capacity and unclear charge storage fundamentals. Here, the strategy of phosphate ion-assisted surface functionalization is used to increase the ammonium ion storage capacity of an α-MoO3 electrode. Moreover, the understanding of charge storage mechanisms via structural characterization, electrochemical analysis, and theoretical calculation is advanced. It is shown that NH4+ intercalation into layered α-MoO3 is not dominant in the A-HSC system; rather, the charge storage mainly depends on the adsorption energy of surface “O” to NH4+. It is further revealed that the hydrogen bond chemistry of the coordination between “O” of surface phosphate ion and NH4+ is the reason for the capacity increase of MoO3. This study not only advances the basic understanding of rechargeable aqueous A-HSC but also demonstrates the promising future of surface engineering strategies for energy storage devices. 相似文献
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