High‐Precision Temperature‐Controllable Metal‐Coated Polymeric Molds for Programmable,Hierarchical Patterning

Nanofabrication is an indispensable process in nanoscience and nanotechnology. Unconventional lithographic techniques are often used for fabrication as alternatives to photolithography because they are faster, more cost‐effective, and simpler to use. However, these techniques are limited in scalability and utility because of the collapse of preprinted structures during step‐and‐repeat processes. This study proposes a new class of temperature‐controllable polymeric molds that are coated with a metal such that any site‐specific patterning can be accomplished in a programmable manner using selective contact‐dewetting lithography. The lithography allows sub‐100 nm patterning, step‐and‐repeat processing, and hierarchical structure fabrication. The programmable feature of the lithography can be utilized for the structural coloring and shaping of objects. Large‐area programmable patterning, semiconductor device manufacturing, and the fabrication of iridescent security devices would benefit from the unique features of the proposed strategy.     

写光波长对光折变空间光调制器分辨率的影响

结合光学实验及数值模拟,对写光波长的变化对基于Bi12SiO20(BSO)光折变晶体的光寻址空间光调制器(SLM)的调制传递函数(MTF)空间频率响应的影响进行了分析.光学实验分析结果和数值模拟分析相吻合,写光波长以及电荷位置对SLM的MTF空间频率响应的影响在本质上得到了统一.根据分析及讨论,较短波长的写光有利于获得较好的MTF空间频率响应.     

Characteristics of Polyaniline/Si Heterojunction Solar Cell By Electrochemical Dye Sensitization

Using the electrochemical polymerization dye sensitization （ECDS） method, polyaniline （PAn）, which is used as top region material in solar cells, is sensitized with direct blue dye（DS）, and sensitized Al grid/DS-PAn/n-Si/Al heterojunction solar cells is prepared by ECDS. Influences of the ECDS on the absorption spectrum and the junction characteristics of the solar cell were discussed, and the output characteristics were measured. The results show that the absorption spectrum of the sensitized PAn films is much wider and stronger in Vis-range; the diode quality factor is about 6.3 and the height of latent barrier potential of p-n junction is 0.89 eV; the short-circuit current and the conversion efficiency of sensitized DS- PAn/Si heterojunction solar cells are greatly improved, which the short-circuit current can increase 6 times, the fill factor is 57% and the efficiency can reach 1.42 % under the illumination of 37.2 W/m^2 , respectively.     

A Multi‐Functional Highly Efficient Upconversion Luminescent Film with an Array of Dielectric Microbeads Decorated with Metal Nanoparticles

Upconversion nanoparticles (UCNPs) have been integrated with photonic platforms to overcome the intrinsically low quantum efficiency limit of upconversion luminescence (UCL). However, platforms based on thin films lack transferability and flexibility, which hinders their broader and more practical application. A plasmonic structure is developed that works as a multi‐functional platform for flexible, transparent, and washable near‐infrared (NIR)‐to‐visible UCL films with ultra‐strong UCL intensity. The platform consists of dielectric microbeads decorated with plasmonic metal nanoparticles on an insulator/metal substrate. Distinct improvements in NIR confinement, visible light extraction, and boosted plasmonic effects for upconversion are observed. With weak NIR excitation, the UCL intensity is higher by three orders of magnitude relative to the reference platform. When the microbeads are organized in a square lattice array, the functionality of the platform can be expanded to wearable and washable UCL films. The platform can be transferred to transparent, flexible, and foldable films and still emit strong UCL with a wide viewing angle.     

LLN中基于能量均衡的高效低时延路由算法

针对有损低功耗网络(Low-power and Lossy Network,LLN)中由于无线链路的有损特性以及节点部署不均匀无法有效实现网络能量均衡,提出一种基于能量均衡的高效低时延路由算法(Efficient Low Latency Routing Algorithm Based on Energy Balance in Low-Power and Lossy Networks,ELLEB-RPL)。该算法采用“ELLEB组网”策略,使得节点能够有效避免在DODAG(Destination Oriented Directed Acyclic Graph)间来回切换;通过采用“最优父节点选择”策略,使得节点选择的父节点达到最优;通过采用“流量自适应分配”策略,达到网络能量均衡的目的。仿真结果表明,ELLEB-RPL在Sink节点平均吞吐量、网络平均寿命以及端到端时延上均有提升。     

基于Credence Gemini500的内嵌式AD转换器测试方法研究

本文中应用Credence公司的Gemini500测试系统对某一SoC芯片内嵌模数转换器进行了测试。根据芯片功能分析和封装形式,对测试板进行了优化设计。根据内嵌式ADC的时序特点进行了测试向量的设计。     

A low power 3.125 Gbps CMOS analog equalizer for serial links

A CMOS analog equalizer is designed to meet the different high speed communication specifications,such as USB 2.0,PCI-E and rapid IO.The proposed circuit architecture could facilitate the wide frequency scale ranging from 1 to 3.125 Gbps by adjusting the locations of pole and zero,so that the circuit can change its response accordingly as the channel characteristic alters.In order to balance the parasitic capacitors in the internal point,symmetric switches are addressed to generate the equal load for dif...     

Simulation of Circuit of Autodyne Sensor with Field-Controlled Transistor

The autodyne sensor operation modelling was carried out. Authors took into account frequency dependence of the field transistor parameters. The shape and a spectrum of generated oscillations in control points of the autodyne sensor circuit were researched, depending on position of an operating point of the transistor. It is revealed, that a condition of the least distortion of the generated oscillations shape is position of a working point of the transistor in the region of camber of its transfer characteristic. Modelling was carried out with Micro-Cap application     

MBE自组装量子点生长和结构形态研究

综述了对自组装量子点形态和生长过程所做的探讨和研究。介绍了关于量子点成核和形态的热力学理论、量子点生长过程的计算机模拟及Ge/Si(001)和InAs/GaAs(001)量子点生长和形态的实验观察。鉴于InAs/GaAs(001)体系的复杂性,把对InAs量子点的观察和研究分为"微观"和"宏观"两种。微观研究对象包括量子点原子尺度上的结构、量子点表面小晶面的晶体学的精确取向等,这些性质可能受热运动的影响比较大,在一定程度上是随机的,它们代表了量子点生长行为的复杂性;宏观研究的对象是指量子点密度、纳米尺度形态等大量粒子统计意义上的集体行为,这些性质和行为可能更具有实际意义。因此作者认为,目前研究量子点生长和形态更为有效的方法应该是探寻以量子点宏观行为所表征的简单性。重点介绍中科院半导体所半导体材料重点实验室最近所做的对InAs/GaAs(001)量子点生长过程的实验观察。结果表明,在一般生长条件下(富As,500℃,0.1ML/s),InAs量子点成核和生长应该都是连续的,没有经历被普遍认为的不连续(一级)相变。按照作者的观察,把InAs量子点成核看作是连续(二级)相变更为贴切。     

子脉冲序列模式Er∶YAG激光消融牙本质的实验观察

研制了一台子脉冲序列模式Er∶YAG激光器,获得了每秒80个和100个子脉冲高能量激光输出,开展了不同脉冲宽度的子脉冲对离体牙本质的激光消融实验。实验中使用的是子脉冲序列模式激光器,其重复频率为20 Hz,脉冲包络能量为45 mJ,子脉冲宽度分别为20,30,40,50μs,在无冷却水雾条件下分别对比了子脉冲宽度对牙本质消融量、牙髓腔温升和坑洞组织形貌的影响。结果表明:在相同的激光脉冲能量下,较窄的子脉冲宽度不仅能够增加消融量,降低牙髓腔温升,从而延长操作时间,而且可以获得更好的消融坑洞组织形貌,牙小管的开放程度较高,有利于黏接修复治疗。