Moisture-Induced Non-Equilibrium Phase Segregation in Triple Cation Mixed Halide Perovskite Monitored by In Situ Characterization Techniques and Solid-State NMR

Environmental stability is a major bottleneck of perovskite solar cells.Only a handful of studies are investigating the effect of moisture on the structural degradation of the absorber.They mostly rely on ex situ experiments and on completely degraded samples,which restrict the assessment on initial and final stage.By combining in situ X-ray diffraction under controlled 85%relative humidity,and live observations of the water-induced degradation using liquid-cell transmission electron microscopy,we reveal two competitive degradation paths leading on one hand to the decomposition of state-of-theart mixed cation/anion(Cs_(0.05)(MA_(0.17)FA_(0.83))_(0.95)Pb(Br_(0.17)I_(0.83))_(3)(CsMAFA)into PbI_(2) through a dissolution/recrystallization mechanism and,on the other hand,to a non-equilibrium phase segregation leading to CsPb_(2)Br_(5) and a Cesium-poor/iodide-rich Cs_(0.05)-x(MA_(0.17)FA_(0.83))_(0.95)Pb(Br_(0.17-2y)I_(0.83)+2y)_(3) perovskite.This degradation mechanism is corroborated at atomic-scale resolution through solid-state ^(1)H and ^(133)Cs NMR analysis.Exposure to moisture leads to a film containing important heterogeneities in terms of morphology,photoluminescence intensities,and lifetimes.Our results provide new insights and consensus that complex perovskite compositions,though very performant as champion devices,are comparatively metastable,a trait that limits the chances to achieve long-term stability.

Ba_2SbGaS_5 : Solid-state Synthesis, Crystal and Electronic Structures, and Property Characterization

Single crystal of Ba2SbGaSs has been synthesized by the high temperature solidstate reaction method. The compound crystallizes in the orthorhombic space group Pnma with a = 12.177（4）, b = 8.880（3）, c = 8.982（3） A, V= 971.4（6） A3, Z = 4, De = 4.284 g/cm3,μ = 14.487 mm-1, F（000） - 1096, the final R = 0.0171 and wR = 0.0384 for all data. The structure comprises an infinite one-dimensional 1∞[SbGaS5]4- anionic chain constructed from the GaS4 tetrahedra and the SbS5 polyhedra via sharing edge alternately. The paralleled 1∞[SbGaS5]4anionic chains engage with each other and form the two-dimensional Sb-Ga-S layer perpendicular to a-axis with the isolated Ba2＋ cations arranged between layers. The IR spectrum and the UV-Vis spectrum have been investigated. Also, the first-principles band structure and density of states calculations indicate that the compound belongs to indirect semiconductor with the band gap of 2.1 eV, which is supported by the UV-Vis diffuse reflectance results.

A lithium–tin fluoride anode enabled by ionic/electronic conductive paths for garnet-based solid-state lithium metal batteries

The high energy density and stability of solid-state lithium metal batteries(SSLMBs)have garnered great attention.Garnet-type oxides,especially Li_(6.4)La_(3)Zr_(1.4)Ta_(0.6)O_(12)(LLZTO),with high ionic conductivity,wide electrochemical window,and stability to Li metal anode,are promising solid-state electrolyte(SSEs)materials for SSLMBs.However,Li/LLZTO interface issues including high interface resistance,inhomogeneous Li deposition,and Li dendrite growth have hindered the practical application of SSLMBs.Herein,a multi-functional Li–SnF_(2) composite anode with Li,LiF,and Li-Sn alloy was specifically designed and prepared.The composite anode improves the wettability to LLZTO,constructing an intimate contact interface between it and LLZTO.Meanwhile,ionic/electronic conductive paths in situ formed at the interface can effectively uniform Li deposition and suppress Li dendrite.The solid-state symmetric cell exhibits low interface resistance(11Ω·cm^(2)) and high critical current density(1.3 mA·cm^(−2))at 25℃.The full SSLMB based on LiFePO_(4) or LiNi_(0.5)Co_(0.2)Mn_(0.3)O_(2) cathode also shows stable cycling performance and high rate capability.This work provides a new composite anode strategy for achieving high-energy density and high-safety SSLMBs.

Foreword to the Journal of Microelectronic Manufacturing

Over 70 years have passed since the first transistor was invented at Bell Labs,New Jersey,USA on 16 December 1947 by William Shockley,John Bardeen and Walter Brattain,which was perhaps the most important electronics event of the 20th century as it later made possible the integrated circuit(IC)and microprocessor that are the basis of modern electronics.The first electronic products were made from individual transistors but before long engineers learnt how to integrate several simultaneously,giving birth to the first IC in 1957.Industry development thereafter followed a predominantly evolutionary process with the number of transistors on an IC increasing exponentially each year,a process known as Moore’s Law after one of the semiconductor industry’s key founding fathers.

微电子专业类课程项目式混合教学模式实践探索

微纳电子技术发展概述专题课程是高等院校微电子科学与工程专业的一门综合类专业选修课程,对提升学生微电子行业的技术领域、前沿动态和发展趋势认知具有重要意义。该文作者基于自身及所在团队老师多年微电子类项目申报经验及国内外热点问题,编写了微纳光电子技术、微机电MEMS系统等主题章节,并以微机电MEMS系统章节为例,将国家自然科学基金项目申报与微电子教学内容相结合,从研究背景、技术瓶颈和解决方案等方面探讨微电子知识在高校科研中的应用,突出微电子学科领域所涉及关键技术的相关概念、特点、应用现状及发展趋势,通过项目式混合教学模式助力微电子专业学生培养模式优化升级。

Fabrication pressures and stack pressures in solid-state battery

Solid-state batteries(SSBs)have received widespread attention with their high safety and high energy density characteristics.However,solid-solid contacts in the internal electrode material and the electrode material/solid electrolyte(SE)interfaces,as well as the severe electrochemo-mechanical effects caused by the internal stress due to the volume change of the active material,these problems hinder ion/electron transport within the SSBs,which significantly deteriorates the electrochemical performance.Applying fabrication pressures and stack pressures are effective measures to improve solid-solid contact and solve electrochemo-mechanical problems.Herein,the influences of different pressures on cathode material,anode material,SEs,and electrode/SEs interface are briefly summarized from the perspective of interface ion diffusion,transmission of electrons and ions in internal particles,current density and ion diffusion kinetics,and the volume changes of Li^(+)stripping/plating based on two physical contact models,and point out the direction for the future research direction of SSBs and advancing industrialization by building the relationship between pressures and SSBs electrochemistry.

Tuning the electron transport behavior at Li/LATP interface for enhanced cyclability of solid-state Li batteries

An interlayer is usually employed to tackle the interfacial instability issue between solid electrolytes(SEs)and Li metal caused by the side reaction.However,the failure mechanism of the ionic conductor interlayers,especially the influence from electron penetration,remains largely unknown.Herein,using Li1.3Al0.3Ti1.7(PO4)3(LATP)as the model SE and LiF as the interlayer,we use metal semiconductor contact barrier theory to reveal the failure origin of Li/LiF@LATP interface based on the calculation results of density functional theory(DFT),in which electrons can easily tunnel through the LiF grain boundary with F vacancies due to its narrow barrier width against electron injection,followed by the reduction of LATP.Remarkably,an Al-LiF bilayer between Li/LATP is found to dramatically promote the interfacial stability,due to the highly increased barrier width and homogenized electric field at the interface.Consequently,the Li symmetric cells with Al-LiF bilayer can exhibit excellent cyclability of more than 2,000 h superior to that interlayered by LiF monolayer(~860 h).Moreover,the Li/Al-LiF@LATP/LiFePO4 solid-state batteries deliver a capacity retention of 83.2%after 350 cycles at 0.5 C.Our findings emphasize the importance of tuning the electron transport behavior by optimizing the potential barrier for the interface design in high-performance solid-state batteries.

柔性无线驱动LED器件的教学实验设计与研究

电磁感应作为无线供电技术的重要理论基础,利用磁通量变化产生感应电动势,为电子产品提供更加便捷和安全的无接触式供电方式。为提升学生的实验兴趣和实验技能,进一步培养其科研和创新意识,设计基于磁耦合共振原理的柔性无线驱动LED器件制作实验。通过对柔性无线驱动LED器件全流程的参与实践,让学生充分了解和学习磁耦合共振原理、电路设计、电路仿真模拟、电路板打印与制作、电学性能检测等相关知识,同时培养学生实验数据分析和解决问题的能力。

DESIGN AND RESEARCH OF QUASI-PLANAR SELF-ALIGNED SILICON AVALANCHE ELECTRON EMISSION ARRAY

The device structure and technical processings of quasi-planar self-aligned silicon avalanche electron emission array arc introduced. The processing step at the edge of electron emission region is about 10nm only and the width of self-aligned current channel of shallow As implantation is about 3μm. Its I-V characteristics show a larger linear region and lower series resistance than that of the previous silicon avalanche electron emission devices. Some of the electron emission characteristics are also discussed in this paper.

Thermionic electron emission in the 1D edge-to-edge limit

Thermionic emission is a tunneling phenomenon,which depicts that electrons on the surface of a conductor can be pulled out into the vacuum when they are subjected to high electrical tensions while being heated hot enough to overtake their work functions.This principle has led to the great success of the so-called vacuum tubes in the early 20 th century.To date,major challenges still remain in the miniaturization of a vacuum channel transistor for on-chip integration in modern solid-state integrated circuits.Here,by introducing nano-sized vacuum gaps(~200 nm)in a van der Waals heterostructure,we successfully fabricated a one-dimensional(1 D)edge-to-edge thermionic emission vacuum tube using graphene as the filament.With the increasing collector voltage,the emitted current exhibits a typical rectifying behavior,with the maximum emission current reaching 200 p A and an ON-OFF ratio of 10;.In addition,it is found that the maximum emission current is proportional to the number of the layers of graphene.Our results expand the research of nano-sized vacuum tubes to an unexplored physical limit of 1 D edge-to-edge emission,and hold great promise for future nano-electronic systems based on it.

信息光电子“微电子化”技术进展和发展探讨

微电子技术使电子器件从分立走向集成,带来成本、可靠性、功耗和体积等方面长达几十年的指数级改善,是电子信息技术能够得到广泛应用的关键。当前,电子信息技术正遭遇带宽和能耗等瓶颈制约,摩尔定律步履维艰。光子作为另一种主要的信息载子,具有高带宽、高速率、低功耗和高并行等特性,信息技术的继续进步必须更为倚重光子。但是,光子器件的成本、可靠性和规模生产性等方面严重落后于电子器件。因此,基于电子器件发展的历史经验,我们提出光电子“微电子化”,强调光电子以“集成”为发展轨道,以“光电融合”为发展方向。以集成为发展轨道,是强调光电子需借鉴微电子的经验,以适应现代信息系统对器件的要求。光电子的集成化发展有3个主要特征:一是芯片平台硅基化,二是集成规模稳步提升,三是生产模式向fabless演进。以光电融合为发展方向,是强调光电子需与微电子相互结合,通过两者的器件一体化、功能融合化来共同解决信息技术目前面临的带宽、速率和功耗等挑战,以适应数字孪生和元宇宙等应用的要求。光电融合主要有芯片和系统两个层面,涉及到单片光电集成、光电共封装(CPO)、混合光电集成、设备解汇聚和光电混合计算等。光电子“微电子化”不仅是一种技术发展指引,还将对信息光电子产业形成重要影响。文章从市场、竞争、企业和产品等角度进行了开放式思考,指出其可能引发产业重塑。信息光电子发展的“微电子化”是信息技术继续前进的客观要求。一方面,光子正由传输技术泛化为信息通信技术(ICT)全域的泛在连接技术,宏尺度上从地面进入海洋和太空,微尺度上从架间、板间进入板内、封装内和片内。另一方面,光子将由带宽提供技术泛化为ICT全域的硬件基础技术,从传输和连接进入计算、处理和路由等复杂功能域。光电子的“微电子化”将使光子不仅有潜力而且有能力充分发挥自身优势以支撑信息技术的继续进步。

面向柔性电子技术的微电子芯片研究进展

随着科技的不断发展,人类的生活和工作方式发生了天翻地覆的变化,电子产品也不例外。传统电子产品通常都是硬质的,形状和尺寸都是固定的,但是对于一些特殊环境和应用场景,这样的电子产品显然并不适用。柔性电子技术应运而生,它通过使用柔性材料和高度集成化的技术,可以制造出任意形状和尺寸的电子产品。其中,微电子芯片作为柔性电子技术的重要分支,也成为科研界和产业界的研究热点。本文综述了面向柔性电子技术的微电子芯片最新研究进展,重点梳理了不同领域柔性微电子芯片的技术突破,介绍了柔性微电子芯片在医疗监测、可穿戴设备、机器人、物联网等新兴领域的应用情况,并对其未来发展进行了展望。

芯片尺寸封装技术

芯片尺寸封装 (CSP)技术是近年来发展最为迅速的微电子封装新技术。文中介绍了该技术的基本概念、特点、主要类型及其应用现状和展望。

“EDA技术”课程实验教学的探索

结合申报"四川省精品课程"和"国家特色专业"的成功经验,从实验安排、实验内容、实验教材和实验平台等角度对该课程的实验教学进行了讨论,目的是使该课程开出特色、突出实用性,成为学生实实在在的"饭碗"课程。

纳米电子技术

微电子技术引发了本世纪的信息革命。纳米科学技术将成为二十一世纪信息时代的核心和国际科学界和工程技术界关注的热点。

CMOS图像传感器中分段电容DAC非理想因素研究(英文)

CMOS图像传感器信号处理中通常采用分段电容DAC产生斜坡参考电压。研究了分段电容DAC精确的电容失配及寄生与其转换精度的关系式。基于对分段电容DAC工作原理的研究,导出了电容失配及寄生模型;针对其分数桥接电容失配、各二进制电容间的失配及寄生电容问题进行了理论分析;对分段电容DAC进行非理想因素仿真,设计了一个采用分段电容DAC的10位单斜ADC并对其进行测试,仿真和测试结果均验证了理论分析的正确性。上述理论分析结果可作为分段电容DAC的设计指导。

双面硅条探测器的研制与测试

研制了双面硅条探测器。探测器灵敏面积为48mm×48mm,厚约300μm,结面和欧姆面的硅条互相垂直,均由相互平行、宽度相等的48条组成,每条宽0.9mm、间距0.1mm。对其电气特性（耗尽偏压、反向漏电流、条间电阻）和探测特性（上升时间、能量分辨、条间串扰）进行了测试。在偏压为-15V时,各条平均反向漏电流小于10nA。对于从结面入射的5.157 MeV的α粒子,前放信号上升时间约45ns,结面各条的能量分辨率约0.6%-0.7%,基本无条间串扰;欧姆面各条能量分辨率较差,存在条间串扰。

微电子技术在生物医学中的应用与发展

微电子技术与生物医学之间有着非常紧密的联系。一方面微电子技术的发展,将大大地推动生物医学的发展,另一方面生物医学的研究成果同样也将对微电子技术的发展起着巨大的促进作用。本文将从生物医学电子学的几个重要发展领域:生物医学传感器、神经电极、植入式电子系统、监护技术、生物芯片、分子和生物分子电子学以及仿生系统等的基本概念出发,结合国际上最新进展介绍微电子技术和生物医学的相互作用与发展,并总结国际上的最新技术和研究动向。

复合静电-磁浸没透镜的宽束曲轴聚焦性质及像差理论

研究了新型的复合静电 磁浸没透镜的曲光轴高斯电子光学性质及像差特性。应用宽束曲轴理论 ,导出了三维局部正交坐标系中的电子运动的中心轨迹方程和曲光轴的近轴轨迹方程 ;利用数学软件Mathematica推导出了复合静电 磁浸没透镜全部曲轴二级像差系数。作为实例 ,文中针对轴上磁场和电场具有某种解析表达式的旋转对称的静电 磁浸没透镜系数 ,计算了它的曲轴高斯聚焦特性和二级像差 。

四管像素满阱容量影响因素研究

在分析光电二极管电容、浮空节点电容以及电荷转移效果这三方面影响满阱容量的基础上,着重讨论了最重要的光电二极管电容对满阱容量的影响,建立了满阱容量的计算模型。将测试结果与模型公式进行拟合,可以预估像素的满阱容量,指导像素设计。为了提高四管像素的满阱容量,提出在钳位光电二极管与浮空节点之间增加P型注入层稳定阱容量的方法。增加P型注入层可以大幅减小积分时间内光电二极管中储存的光生电子向浮空节点方向的泄漏,从而有效稳定阱容量。测试结果表明,在多种工艺条件下,像素的满阱容量从基本可以忽略提升至十万个电子的量级。