PL Emission and Shape of Silicon Quantum Dots
势垒硅掺杂对GaN基LED极化电场及其光电性能的影响
势垒硅掺杂对GaN基LED极化电场及其光电性能的影响张正宜;王超【摘要】势垒硅掺杂对InGaN量子阱中的电场及LED器件的光电性能有着重要的影响.采用6×6 K·P方法计算了不同势垒硅掺杂浓度对量子阱中电场的变化,研究表明当势垒硅掺杂浓度>1e18 cm-3时,阱垒界面处的电场强度会变大,这主要是由于硅掺杂浓度过高导致量子阱中界面电荷的聚集.进一步发现随着势垒掺杂浓度的升高,总非辐射复合随之增加,其中俄歇复合增加,而肖克莱-霍尔-里德复合随之减少,这是由于点陷阱的增大形成了缺陷能级.电流电压曲线表明势垒掺杂可有效改善GaN基LED的工作电压,这归于掺杂浓度的提高改善了载流子的传输特性.当掺杂浓度为1e18 cm-3时,获得了较高的内量子效率,这主要是由于适当的势垒掺杂降低了量子阱中界面电荷的损耗.【期刊名称】《发光学报》【年(卷),期】2018(039)010【总页数】6页(P1445-1450)【关键词】势垒;量子阱;极化电场;光电性能【作者】张正宜;王超【作者单位】山西交通职业技术学院信息工程系, 山西太原 030031;兰州交通大学光电技术与智能控制教育部重点实验室,甘肃兰州 730070【正文语种】中文【中图分类】TN321.81 引言InGaN半导体材料具有纤锌矿晶体结构和直接能隙结构，通过改变In原子在InGaN中的比例，可实现从0.7 eV到6.2 eV的能隙调控，从而可以在整个可见光范围内通过电致发光[1-2]。
InGaN LED被广泛应用到通用照明和显示领域。
对于氮化物发光二极管器件来说，InGaN多量子阱结构是其最重要的组成部分。
目前，对于InGaN多量子阱的材料结构设计及机理方面做了大量的研究工作，其中，包括量子阱p型掺杂、梯度量子阱、三角量子阱的设计等改变量子阱内的极化电场，采用lnGaN或者InAlGaN作为势垒材料来调节多量子阱中的应力[3]，对InGaN多量子阱垒层掺杂Si来改善器件的光学及电学性能[4-6]。
InAs_GaSb超晶格中波焦平面材料的分子束外延技术
取得令人瞩目的成绩，但目前报道的焦平面探测器 性能与其理论预期还有相当大的差距．主要的制约
因素是材料性能尚有待进一步提高．另外，国内对该
方向的研究尚处于起步阶段，要赶上国际先进水平，
更需要在材料生长与性能表征上加大研究力度．
本文报道用ＭＢＥ技术生长ＩｎＡｓ／ＧａＳｂ超晶格材 料及其性能的研究．我们采用微分相衬显微镜、原子
ｏｆ ｉｎｆｒａｒｅｄ ｉｍａｇｅ ｍａｔｅｒｉａｌｓ ａｎｄ ｄｅｖｉｃｅｓ，Ｓｈａｎｇｈａｉ Ｉｎｓｔｉｔｕｔｅ ｏｆ Ｔｅｃｈｎｉｃａｌ Ｐｈｙｓｉｃｓ， Ｃｈｉｎｅｓｅ Ａｃａｄｅｍｙ ｏｆ Ｓｃｉｅｎｃｅｓ，Ｓｈａｎｇｈａｉ
２０００８３，Ｃｈｉｎａ）
ｏｎ
Ａｂｓｔｒａｃｔ：Ｔｈｅ ｇｒｏｗｔｈ ｏｆ ｍｉｄ－ｗａｖｅｌｅｎｇｔｈ ｉｎｆｒａｒｅｄ ＩｎＡｓ／ＧａＳｂ ｓｕｐｅｒｌａｔｔｉｃｅ
台阶高度为０．３６５ｎｍ，与一个单原子层的厚度基本 吻合．测试范围２¨ｍ ｘ２阻ｍ内的平均粗糙度在１— １．５ Ａ之间，说明样品具有原子级平整的表面．因此
在后续的实验中，ＧａＳｂ的生长温度采用４８５℃， ＩｎＡｓ／ＧａＳｂ超晶格的生长温度采用４５０℃． 第二组材料是在获得最佳的衬底温度条件下，
行的，超晶格材料的Ａｓ源和ｓｂ源分别由Ａｓ带阀的 裂解炉和ｓｂ带阀的裂解炉提供的Ａｓ２和ｓｂ２．Ｉｎ源 和Ｇａ源分别是７Ｎ的高纯金属Ｉｎ和Ｇａ．实验采用
（１００）晶向的ＧａＳｂ衬底，衬底表面脱氧过程由在线
的反射式高能电子衍射（ＲＨＥＥＤ）花样监控，材料外 延生长的速率由ＲＨＥＥＤ强度振荡曲线获得，Ｉｎ／Ａｓ
和Ｇａ／Ｓｂ的束流比由在线的离子规测量得到，衬底
设计了３种不同的界面结构如图３所示，主要改变 了界面层中Ｉｎ和ｓｂ的开关时间长短及开关顺序． 由于ＩｎＡｓ的晶格常数比ＧａＳｈ的晶格常数ｔｈ７．５％，
溶液空间限域法制备有机-无机杂化卤化铅钙钛矿单晶薄膜及其器件应用研究进展
第53卷第4期2024年4月人㊀工㊀晶㊀体㊀学㊀报JOURNAL OF SYNTHETIC CRYSTALS Vol.53㊀No.4April,2024溶液空间限域法制备有机-无机杂化卤化铅钙钛矿单晶薄膜及其器件应用研究进展张庆文,单东明,张㊀虎,丁㊀然(吉林大学电子科学与工程学院,集成光电子学国家重点实验室,长春㊀130012)摘要:近年来,有机-无机杂化卤化铅钙钛矿材料因其出色的光电特性在国际上备受瞩目,并已成功应用于太阳能光伏㊁光电探测㊁电致发光等多个领域㊂目前绝大部分器件研究都集中在钙钛矿多晶材料上,但钙钛矿单晶材料拥有更低的缺陷态密度㊁更高的载流子迁移率㊁更长的载流子复合寿命㊁更宽的光吸收范围,以及更高的稳定性等优异的性质,可有效减少载流子传输过程中的散射损失,以及在晶界处的非辐射复合,并抑制离子迁移所引起的迟滞效应㊂采用钙钛矿单晶薄膜作为器件有源层有望制备性能更高效且更稳定的钙钛矿光电器件㊂目前,已报道的多种钙钛矿单晶薄膜制备方法包括溶液空间限域法㊁化学气相沉积法㊁自上而下加工法等,其中溶液空间限域法的发展和应用最为广泛㊂本文聚焦利用溶液空间限域法制备高质量钙钛矿单晶薄膜的相关方法,以及钙钛矿单晶薄膜在光电探测器㊁太阳能电池㊁场效应晶体管和发光二极管等相关器件应用中的研究进展,并对钙钛矿单晶薄膜及其光电器件的未来发展趋势进行了展望㊂关键词:钙钛矿半导体材料;溶液空间限域法;钙钛矿单晶薄膜;光电子器件;单晶薄膜生长中图分类号:O78;O484;TN36㊀㊀文献标志码:A ㊀㊀文章编号:1000-985X (2024)04-0572-13Research Progress on Preparation of Organic-Inorganic Hybrid Lead Halide Perovskite Single-Crystalline Thin-Films by Solution-Processed Space-Confined Method and Their Device ApplicationsZHANG Qingwen ,SHAN Dongming ,ZHANG Hu ,DING Ran(State Key Laboratory of Integrated Optoelectronics,College of Electronic Science and Engineering,Jilin University,Changchun 130012,China)㊀㊀收稿日期:2023-11-20㊀㊀基金项目:国家重点研发计划青年科学家项目(2022YFB3607500);国家自然科学基金(62274076)㊀㊀作者简介:张庆文(1999 ),男,山东省人,硕士研究生㊂E-mail:zhangqw1012@ ㊀㊀通信作者:丁㊀然,教授,博士生导师㊂E-mail:dingran@Abstract :In recent years,organic-inorganic hybrid lead halide perovskite materials have attracted much attention in the world because of their excellent photoelectric properties,and have been successfully applied in many fields such as solar photovoltaic,photoelectric detection,electroluminescence and so on.At present,most of the device research focuses on perovskite polycrystalline materials,but perovskite single crystal materials have excellent properties such as lower defect state density,higher carrier mobility,longer carrier recombination lifetime,wider light absorption range and higher stability,which can effectively reduce the scattering loss during carrier transport and non-radiative recombination at the grain boundary,and inhibit the hysteresis effect caused by ion ing perovskite single crystal thin film as the active layer of the device is expected to produce more efficient and stable perovskite photoelectric devices.At present,many preparation methods of perovskite single crystal films have been reported,mainly including solution-processed space-confined method,chemical vapor deposition method,top-down processing method,etc.Among them,solution-processed space-confined method is the most widely developed and applied.This paper focuses on the preparation of high-quality perovskite single crystal thin films by solution-processed space-confined method,and the research progress of perovskite single crystal thin films in photodetectors,solar cells,field effect transistors,light-emitting diodes and other related devices,and prospects the future development trend of perovskite single crystal thin films and photoelectric devices.㊀第4期张庆文等:溶液空间限域法制备有机-无机杂化卤化铅钙钛矿单晶薄膜及其器件应用研究进展573㊀Key words:hybrid perovskite semiconductor;solution-processed space-confined method;perovskite single-crystalline thin-film;optoelectronic device;growth of single crystal thin film0㊀引㊀㊀言近年来,有机-无机杂化卤化铅钙钛矿材料因高的光吸收系数[1]㊁高的载流子迁移率[2-3]㊁长的载流子扩散距离[4]㊁带隙可调谐[5-7]等优异的光电性能,引起了科研界和产业界的广泛关注㊂尤其是在光伏器件领域,钙钛矿电池的功率转换效率(power conversion efficiency,PCE)从最初的3.8%[8]攀升到目前的25.9%[9],发展速度出人意料且远超其他光伏材料体系㊂理论计算得到单结钙钛矿电池的最高转换效率可达33%,这一效率优于晶体硅的理论极限效率29.4%㊂除光伏领域外,钙钛矿材料在光电探测[5,10-15]㊁电致发光[16-19]㊁光泵激光[20-23]和辐射探测[24-26]等诸多光电领域也展现出巨大的应用前景㊂有机-无机杂化卤化铅钙钛矿材料化学结构式通常为ABX3,一般为立方体或八面体结构[27],对于典型的三维钙钛矿材料,其中A代表一价阳离子(如MA+㊁FA+等),B代表二价Pb2+阳离子,X为一价卤素阴离子(如Cl-㊁Br-㊁I-等)㊂在钙钛矿材料中,B离子位于立方晶胞的中心[28],被6个X离子包围形成配位立方八面体结构㊂钙钛矿光电器件有源层材料以多晶薄膜为主,多晶材料虽然在器件应用方面已展现出卓越的性能,但是内部存在大量晶界,且在晶界处存在高密度的晶格位错,以及无序的晶粒生长,从而导致薄膜内存在大量的晶格缺陷和可自由移动的离子㊂多晶膜内大量晶粒㊁晶界㊁空隙和表面缺陷等,会显著增大非辐射复合过程并诱使激子猝灭,严重限制光电及电光转换效率[29-30]㊂同时,在外场作用下钙钛矿多晶膜中会产生明显的离子迁移现象,移动的离子会抑制自由载流子的感生㊁积累与传输,也将极大影响器件的光电性能[31]㊂相比之下,钙钛矿单晶拥有更低的缺陷态密度㊁更长的载流子扩散长度㊁更长的载流子复合寿命㊁更宽的光吸收范围,以及更高的稳定性等[32-33]㊂这些优秀的本征特性为克服以上挑战提供了良好的载体,有望制备性能更高效且更稳定的钙钛矿光电器件㊂从晶体形态学角度区分,钙钛矿单晶材料主要可分为块体[34-35]和薄膜两种类型[36-38]㊂相比于单晶块体材料,单晶薄膜更易于与传统半导体工艺相集成,并有望制备性能更加优越的光电器件,更因其突出的柔性[39]和机械性,在未来柔性电子器件领域也展现出良好的应用前景㊂目前,已报道的钙钛矿单晶薄膜制备方法中,主要包括溶液空间限域法[36-37,40]㊁化学气相沉积法[41-44]㊁自上而下加工法[13,45-48]等,其中溶液空间限域法的发展和应用最为广泛㊂由于单晶各向异性生长,为了有效控制单晶薄膜厚度,抑制薄膜沿垂直纵向方向生长,并且提高水平横向方向的生长速率㊁增大薄膜的表面积,常引入空间结构限制策略,实现可控制备钙钛矿单晶薄膜㊂本文聚焦利用溶液空间限域法制备高质量钙钛矿单晶薄膜的相关技术方法,以及钙钛矿单晶薄膜在光电探测器㊁太阳能电池㊁场效应晶体管和电致发光器件等相关器件应用中的研究进展㊂同时,对未来钙钛矿单晶薄膜材料的发展及其应用所面临的难题提出可行的解决方案㊂1㊀钙钛矿单晶薄膜生长策略目前,溶液法生长钙钛矿单晶块体技术较为成熟,包括冷却结晶法[4,49-52]㊁逆温结晶法[46,53-57]㊁反溶剂扩散法[58-62]等方法,但单晶块体的厚度较厚,展现出较高的光吸收损耗和较长的激子扩散距离,不适于垂直结构型光电器件的应用㊂为了进一步扩展钙钛矿单晶材料在光电器件领域的应用,急需开发厚度和形貌可控㊁重复性高的钙钛矿单晶薄膜制备方法㊂2016年,陕西师范大学刘生忠教授团队报道采用空间限域结合动态流反应系统的生长方法,通过控制两个玻璃片之间的间隙大小,确保钙钛矿单晶薄膜在预设的限域空间结构内生长,达到单晶薄膜厚度可控的目的,如图1(a)所示[37]㊂利用蠕动泵驱动空隙中溶液流动,为单晶薄膜生长提供源源不断的前驱体溶液,最终实现一系列厚度约为150μm的MAPbI3单晶薄片㊂然而,微米厚度的钙钛矿单晶薄膜依然无法满足垂直结构型器件的需求,通过施加外部压力的方式来控制几何限域空间的间隙距离,达到进一步减薄钙钛矿单晶薄膜的作用㊂2016年,中国科学院化学研究所胡劲松研究员团队设计如图1(b)所示装置,实现可控制备厚度均匀的钙钛矿单晶薄膜生长方法[36]㊂实验具体流程是将两个平面衬底夹在一起,通过控制夹具的压力来限制几何限域空间间隙,再垂直浸入钙钛矿前驱体溶液中,在毛细力的作用下溶液会填充满整个限域空间,然后加热底部前驱体溶液,控制溶剂挥发速率,形成底部饱和㊁顶部过574㊀综合评述人工晶体学报㊀㊀㊀㊀㊀㊀第53卷饱和的溶液环境,由于温度差引起的热对流,底部的溶液不断向顶部流动补充,为限域空间内生长钙钛矿单晶薄膜提供充足的前驱体溶液㊂制备的单晶薄膜具有厚度从纳米至微米可调㊁表面积达到亚毫米尺寸㊁横纵比可达~105等特点㊂同时,该方法可将钙钛矿单晶薄膜制备在各种衬底(如玻璃㊁石英㊁氧化铟锡(indiumtin oxide,ITO)㊁氟掺杂氧化锡(F-doped tin oxide,FTO))上,其厚度只取决于两个衬底之间的间隙距离,不同厚度的薄膜呈现出多彩均匀的颜色㊂图1㊀溶液空间限域法中厚度可控策略制备钙钛矿单晶薄膜㊂(a)溶液空间限域结合动态流反应系统生长法[37];(b)溶液空间限域法生长厚度可调的钙钛矿单晶薄膜[36]Fig.1㊀Strategies for the growth of thickness-controlled perovskite single-crystalline thin-films.(a)Schematic diagram of the geometry-confined dynamic-flow reaction system[37];(b)schematic diagram of the solution-processed space-confined growthmethod for perovskite single-crystalline thin-films[36]为了扩大钙钛矿单晶薄膜的横向尺寸,从晶体成核动力学角度出发,降低溶液空间限域法中衬底的表面能,将有助于提高溶剂中离子的扩散速度和扩散距离,诱导晶体沿横向方向加速生长㊂2017年,美国北卡罗来纳大学教堂山分校黄劲松教授团队提出对衬底表面进行疏水处理,在ITO衬底表面旋涂疏水的聚[双(4-苯基)(2,4,6-三甲基苯基)胺](Poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine,PTAA)空穴传输层材料,再用两片PTAA修饰后的ITO衬底构建限域空间,在空间内滴加MAPbBr3前驱体溶液后,将衬底结构置于㊀第4期张庆文等:溶液空间限域法制备有机-无机杂化卤化铅钙钛矿单晶薄膜及其器件应用研究进展575㊀110ħ热台上[1]㊂对比PTAA处理和未处理的衬底所构建限域空间内前驱体溶液的扩散差异,从图2(a)不难发现,由于疏水材料处理的衬底表面具有较低的表面能,将加速前驱体溶液中离子的扩散速率,解决生长过程中离子长程输运差的问题,有助于减少多晶成核结晶概率,同时增大单晶薄膜的横向生长尺寸㊂基于该衬底修饰方法,实现MAPbBr3单晶薄膜厚度可控制在10~20μm,横向截面尺寸可达数十mm2,该工作证明了对衬底表面进行合理改性对于控制钙钛矿单晶薄膜横向生长至关重要㊂2020年,北京大学马仁敏教授团队采取对衬底表面进行特异性处理的策略[63]㊂具体方式是对玻璃衬底进行不同的亲疏水处理,由于具有特异性的亲疏水能力,衬底展现出大小不同的溶液接触角㊂在观测亲疏水能力与单晶成核密度之间的关系后,发现从亲水到疏水的转变过程中,衬底表面的成核密度显著降低㊂分析其原因是亲水表面的成核自由能垒相对低于疏水条件下的表面成核自由能垒,从而拥有较快速的成核速率;并且亲水表面更易于吸附和捕获前驱体溶液中的离子,而降低了离子的扩散速率,导致单晶结晶速率较为缓慢㊂因此,疏水处理的衬底可有效降低单晶成核密度,并且加快单晶生长速率,更易于制备大尺寸的钙钛矿单晶薄膜㊂制得的MAPbBr3单晶薄膜边长尺寸达到1cm,厚度控制在10μm,同时展现出较好的结晶质量,薄膜陷阱态密度仅为1011cm-3,载流子迁移率超过60cm2/(V㊃s)㊂除了衬底修饰策略,衬底自身独特的表面特征也有助于钙钛矿单晶薄膜的生长㊂2020年,天津理工大学吴以成教授团队以云母作为溶液空间限域法的生长衬底[64],如图2(b)所示,将含有适量油酸(oleic acid,OA)的钙钛矿前驱体溶液滴加到两片云母组成的间隙中,旋转云母衬底去除多余的前驱体溶液,然后放置于热板上加热,最终获得超薄的MAPbBr3单晶薄膜㊂该方法是基于云母表面的钾原子与钙钛矿中卤素原子之间会产生较强的相互作用,导致界面能降低并促进钙钛矿单晶薄膜在云母表面横向生长,同时油酸作为表面改性剂附着在钙钛矿表面,抑制钙钛矿单晶薄膜沿纵向方向的生长,最终成功制备出厚度仅为8nm㊁横向尺寸可达数百微米的MAPbBr3单晶薄膜㊂图2㊀溶液空间限域法中衬底修饰策略制备钙钛矿单晶薄膜㊂(a)PTAA处理和未处理的ITO衬底结构中前驱体溶液扩散速度对比图[1];(b)云母衬底上生长钙钛矿单晶薄膜流程示意图[64]Fig.2㊀Substrate modification for the growth of perovskite single-crystalline thin-films.(a)Comparison of the diffusion rate of precursor solution within the PTAA treated and untreated ITO substrates[1];(b)growth of perovskite single-crystalline thin-films on mica substrates[64]钙钛矿单晶薄膜的生长开始于成核阶段,考虑到处于复杂溶液环境中,晶体将发生各向异性生长,容易形成多个晶核,并诱使出现晶畴㊁晶界等结构,严重影响钙钛矿单晶成膜的结晶质量[65]㊂为解决这一问题,科研人员提出了一种晶种法技术策略,首先生长钙钛矿单晶种子,再将种子转移到目标衬底,最后在合适的溶液环境中再结晶生长形成高质量的钙钛矿单晶薄膜㊂2018年,中国科学院化学研究所宋延林研究员团队提出了一种溶液空间限域结合晶种印刷法的生长策略,通过晶种再生长的方式,实现了厚度可控㊁重复性好㊁576㊀综合评述人工晶体学报㊀㊀㊀㊀㊀㊀第53卷结晶质量高的钙钛矿单晶薄膜[66]㊂如图3(a)所示,首先使用喷墨打印技术将钙钛矿前驱体溶液选择性滴加在目标衬底上,随着前驱体溶液的挥发,形成规则排布的钙钛矿单晶种子㊂获得的钙钛矿单晶种子将有效抑制无序成核结晶现象㊂然后,将载有钙钛矿单晶种子的衬底转移并浸入到钙钛矿前驱体饱和溶液中,置于热台上加热结晶后,通过控制钙钛矿单晶种子的数量和尺寸,最终制备出批量的毫米级钙钛矿单晶薄膜㊂2021年,韩国首尔大学Lee教授团队进一步拓展了晶种生长法,结合种子转移技术,如图3(b)所示[67]㊂首先在两片玻璃片中注入前驱体溶液,玻璃片之间由厚度为25μm的聚四氟乙烯(polytetrafluoroethylene,PTFE)薄膜隔开,在110ħ的加热温度下,过饱和的钙钛矿前驱体溶液成核结晶,形成厚度为23μm㊁尺寸为100~200μm 的MAPbBr3单晶种子㊂然后,挑选出单个种子转移至一个密封式液体池腔体中,随着浓度为1mol/L的MAPbBr3前驱体溶剂以5μL/min速率源源不断地流入液体池腔体内,基于逆温结晶法,MAPbBr3单晶薄膜将匀速生长,最终制得了高质量㊁大尺寸的MAPbBr3单晶薄膜,其厚度为40μm,表面积可达16.23mm2,表面粗糙度为0.51nm,缺陷态密度仅有7.61ˑ108cm-3㊂图3㊀溶液空间限域法中晶种法策略制备钙钛矿单晶薄膜㊂(a)溶液空间限域结合晶种印刷法制备钙钛矿单晶薄膜技术流程示意图[66];(b)晶种生长法结合晶种转移技术制备钙钛矿单晶薄膜技术流程示意图[67]Fig.3㊀Seed-induced methods for the growth of perovskite single-crystalline thin-films.(a)Technical flow diagram of preparation of perovskite single crystal film by solution-processed space-confined combined with seed printing[66];(b)process flow diagram of preparation of perovskite single crystal thin film by seed growth and seed transfer technology[67]图案化生长钙钛矿单晶薄膜对于推动钙钛矿单晶材料面向集成化光电器件应用至关重要㊂其主要思路是通过引入周期性的模板,构建结构化限域空间用于生长图案化钙钛矿单晶[68-74]㊂2021年,合肥工业大学罗林保教授团队利用高密度数字视频光盘(digital video disc,DVD)上的沟道作为结构化限域空间用于溶液空间限域法,如图4(a)所示[71]㊂首先,将聚二甲基硅氧烷(polydimethylsiloxane,PDMS)溶液旋涂在准备好的DVD磁盘上,固化后形成与磁盘沟道结构和形貌一致的PDMS模板㊂然后,在亲水性衬底上滴加钙钛矿前驱体溶液,溶液在亲水衬底上形成一层均匀的液膜,再将表面具有周期性沟道结构的PDMS模板覆盖其上,前驱体溶液便被重新分配并限制在PDMS模板与亲水性衬底形成的纳米沟道之间㊂放置于热台上加热之后,晶体沿着纳米沟道不断生长,最终形成规则且均匀的钙钛矿单晶阵列,得到的钙钛矿单晶阵列的结构完全与磁盘沟道形貌相一致,并可实现在不同衬底上生长大规模钙钛矿单晶阵列结构㊂2022年,苏州大学揭建胜教授团队开发了类似的三维限制结晶方法,在三维结构化的微通道模板上方利用一个三角形PDMS 基板协助溶液剪切过程,用于生长钙钛矿单晶阵列,PDMS模板紧密地附着在微通道表面,避免了溶液剪切㊀第4期张庆文等:溶液空间限域法制备有机-无机杂化卤化铅钙钛矿单晶薄膜及其器件应用研究进展577㊀过程中对微通道的破坏,同时利用PDMS模板表面的疏水性,可以有效防止溶液黏附在三角形PDMS基板上,如图4(b)所示[72]㊂在底部进行加热的情况下,缓慢移动三角形玻璃基板,钙钛矿前驱体溶液逐渐挥发结晶,最终形成与模板结构相同的MAPbI3单晶阵列㊂为了进一步提高钙钛矿单晶阵列横向尺寸,韩国汉阳大学Sung教授团队引入滚筒印刷技术,如图4(c)所示[73]㊂首先,钙钛矿前驱体溶液加在180ħ加热的基板衬底上,通过旋转图案化的PDMS模具包裹的圆柱形金属滚轮,PDMS模具上具有宽度为10mm㊁深度为200nm的周期性阵列,前驱体溶液被限制在模具和基板衬底之间,随着前驱体溶液的迅速蒸发而结晶,最终制得的钙钛矿单晶薄膜阵列与滚筒图案完全一致㊂成功实现了总宽度为10mm,周期尺寸为400nm,厚度为200nm的MAPbI3单晶薄膜阵列㊂利用该方法不仅可以在横向方向上约束钙钛矿单晶的生长,并且实现滚筒印刷制备大尺度钙钛矿单晶薄膜阵列的目的㊂通过上述总结,围绕溶液空间限域法制备大尺寸㊁高质量钙钛矿单晶薄膜,详细阐述了从厚度可控㊁衬底修饰㊁晶种生长㊁图案化生长等几个主要方面的生长和制备方法,相关性能参数如表1所示,对于未来实现可控制备钙钛矿单晶薄膜材料,进一步扩展其在光电器件领域的应用至关重要㊂图4㊀溶液空间限域法中图案化生长策略制备钙钛矿单晶薄膜㊂(a)磁盘沟道模板生长钙钛矿单晶阵列的技术流程图[71];(b)三维限制结晶方法生长钙钛矿单晶阵列装置示意图[72];(c)滚筒印刷技术制备大尺度钙钛矿单晶阵列的装置流程图[73] Fig.4㊀Periodic structures for the growth of perovskite single-crystalline thin-films.(a)Digital channel template for the growth of perovskite single-crystalline arrays[71];(b)schematic diagram of apparatus for growing perovskite single crystal array by a three-dimensional restricted crystallization method[72];(c)flow chart of device for preparing large-scale perovskite singlecrystal array by roller printing technology[73]578㊀综合评述人工晶体学报㊀㊀㊀㊀㊀㊀第53卷表1㊀溶液空间限域法及其改进策略制备钙钛矿单晶薄膜的相关性能参数Table1㊀Performance parameters of the perovskite single-crystalline thin-films prepared by solution-processedspace-confined method and its improvement strategySolution-processed space-confined method and its improvement strategy Perovskitematerial type Thickness/μmDensity of defectstates/cm-3Carrier mobility/(cm2㊃V-1㊃s-1)Surface dimension ReferenceDynamic-flow reaction system MAPbI3~1506ˑ10839.6 5.84mmˑ5.62mm[37] Thickness controlledgrowth method MAPbBr30.01~1 4.8ˑ101015.7Hundreds of microns[36]Substrate treatment MAPbI310~40Electron:36.8ʃ3.7Hole:12.1ʃ1.5Tens of square millimeters[1] Substrate specific processing MAPbBr3~10 1.6ˑ1011>601cm[63] Mica substrate MAPbX30.008~0.01436.5Hundreds of microns[64] Seed printing method MAPbX3,CsPbBr30.1~10 2.6ˑ101014000μm2[66] Seed transfer technology MAPbBr3407.61ˑ10816.23mm2[67] Digital channeltemplate method MAPbI3~0.065cycle:760nm[71] Three-dimensional confinedcrystallization method MAPbI30.5~58.5ˑ1010cycle:8μm[72] Rolling mould printingtechnology MAPbI30.2or0.545.64cycle:400nm[73] 2㊀钙钛矿单晶薄膜器件应用钙钛矿单晶薄膜因其高的光吸收系数㊁高的载流子迁移率㊁长的载流子扩散长度㊁带隙可调谐等优异的光电性能,被广泛应用于光电探测器㊁太阳能电池㊁场效应晶体管㊁发光二极管等器件中㊂光电探测器是基于传统光电效应将光信号转变为电信号的器件装置,其在光通信㊁激光雷达㊁医疗诊断㊁安防监控等多个领域应用广泛㊂传统光电探测器多以无机半导体材料为主,例如Si㊁GaAs㊁GaN等材料[11]㊂近年来,随着有机-无机杂化卤化物钙钛矿半导体材料的出现,其展现出的巨大的应用潜力,有望促进光电探测器在成本和性能上取得进一步的提升和跨越㊂大量研究表明,由于较低的光吸收损耗和理想的激子扩散距离,钙钛矿单晶薄膜光电探测器[68-69,75-77]相比于单晶块体探测器,在光电探测方面已展露出明显的性能优势㊂2015年,阿卜杜拉国王科学大学Bakr教授团队首次报道利用直接生长在ITO玻璃衬底上的MAPbCl3单晶薄膜,制备一种具有金属-半导体-金属器件结构的光电导型探测器[54],并展现出出色的光电探测性能,具有较高的探测率与开关比,响应时间在ms数量级,这与当时商用的III-V族半导体光电晶体管的性能几乎相当㊂2017年,黄劲松团队利用MAPbBr3单晶薄膜制作了垂直器件结构为p-i-n型的Cu/BCP/C60/MAPbBr3/PTAA/ITO钙钛矿单晶探测器[78],如图5(a)所示,该光电探测器的探测率(D∗)高达1.5ˑ1013Jones㊂由于单晶薄膜较低的缺陷态密度,探测器对于弱光探测极为敏感,探测最低可达pW/cm2量级,同时线性动态范围高达256dB,是当时报道最高的结果㊂2018年,马仁敏教授团队系统性研究了光电探测器性能与单晶薄膜厚度之间的依赖关系[14]㊂发现随着钙钛矿单晶薄膜的厚度从10μm降低到几百nm,光电探测器的探测能力提升了2个数量级,增益提升了4个数量级㊂通过优化钙钛矿单晶薄膜的厚度以及结晶度,器件的增益可达5ˑ107,增益带宽积为70GHz㊂钙钛矿材料具有可低温㊁液相制备的特点,并可与多种柔性衬底相兼容,制备可弯折的柔性光电子器件㊂同时,钙钛矿单晶薄膜展现出较好的柔性和机械性,可用于制备柔性钙钛矿单晶薄膜光电探测器㊂为此, 2020年,马仁敏教授团队引入超薄钙钛矿单晶薄膜作为有源层,制备了高性能的柔性光电探测器[39],如图5 (b)所示,该光电探测器的单晶薄膜厚度仅为20nm,器件响应度高达5600A/W,在经过1000次循环弯折后,探测器的光电流和开关比没有出现明显的下降,展现出较好的弯折稳定性㊂高质量的钙钛矿单晶纳米线阵列有利于限制载流子在几何通道内输运,提高载流子的迁移率和扩散距离㊂2021年罗林保教授团队制备的基于MAPbI3单晶纳米线阵列的光电探测器[71],在520nm入射光照射下,随入射光功率的升高,该光电探㊀第4期张庆文等:溶液空间限域法制备有机-无机杂化卤化铅钙钛矿单晶薄膜及其器件应用研究进展579㊀测器的光电流呈线性递增,最低暗电流为0.3nA,最高光电流达350nA,总开关比高达1.2ˑ103㊂同时,该探测器的响应度为20.56A/W,探测率达到4.73ˑ1012Jones㊂由于钙钛矿单晶纳米线阵列展现出良好的偏振敏感性,该类型器件也适用于探测线偏光的偏振度㊂为了解决钙钛矿材料中铅毒性[79]和不稳定性的问题,2020年,中山大学匡代彬教授团队在ITO玻璃上原位生长不含铅元素的全无机Cs3Bi2I9单晶薄膜并制备了相应的光电探测器[80]㊂制得的Cs3Bi2I9钙钛矿单晶薄膜的陷阱态密度比多晶材料低3个数量级,载流子迁移率也高出3.8ˑ104倍㊂这些优异的性质有利于实现高性能的光电探测器,基于此材料制备的垂直结构型光电探测器的开关比高达11000㊂而且,在未封装的情况下,处在潮湿环境中1000h之后,该钙钛矿单晶薄膜光探测器的光电流仍维持初始值的91%,体现了该材料出色的环境稳定性㊂由于钙钛矿多晶薄膜内存在大量的晶界㊁空穴和缺陷态等,太阳能电池存在显著的非辐射复合能量损失,限制了钙钛矿太阳能电池PCE的进一步提升㊂而无晶界㊁低缺陷态密度的钙钛矿单晶薄膜成为解决材料内在问题及器件PCE的理想材料体系㊂2017年,中国科学院深圳先进技术研究院李江宇教授团队在FTO/TiO2衬底上直接生长MAPbI3单晶薄膜,并制造了相应的钙钛矿单晶薄膜太阳能电池,该电池器件的PCE达到了8.78%[81]㊂同年,黄劲松教授团队利用在PTAA空穴传输层上直接生长的MAPbI3单晶薄膜,构建器件结构为ITO/PTAA/MAPbI3/PCBM/C60/BCP/Cu的太阳能电池器件,如图5(c)所示[1]㊂通过优化钙钛矿单晶薄膜厚度,其电池的光谱响应范围可以扩展到820nm,比相对应的多晶薄膜材料的光谱响应要宽20nm,器件的最佳短路电流密度J sc为20.5mA/cm2,开路电压V oc为1.06V,填充因子(fill factor,FF)为74.1%,PCE可达16.1%㊂在使用MAI离子溶液对单晶薄膜表面进行钝化处理之后,有效降低了MAPbI3单晶薄膜表面的电荷陷阱,器件最佳PCE提升到17.8%㊂2019年,Bakr教授团队利用20μm厚的MAPbI3单晶薄膜制备太阳能电池,器件结构为ITO/PTAA/MAPbI3/C60/BCP/Cu[82]㊂该钙钛矿单晶薄膜电池器件的PCE达到21.09%,填充因子FF为84.3%㊂之后,该团队通过优化前驱体溶液,采用碳酸丙烯酯(propylene carbonate,PC)和γ-丁内酯(1,4-butyrolactone,GBL)的混合溶剂,90ħ下生长MAPbI3钙钛矿单晶薄膜㊂基于此单晶材料制备的钙钛矿太阳能电池的V oc明显提高,PCE达到21.9%[84]㊂2021年,该团队在之前的器件结构基础上,将钙钛矿单晶的成分改为混合阳离子FA0.6MA0.4PbI3钙钛矿单晶,如图5(d)所示,制备的钙钛矿太阳能电池对近红外响应要比纯FAPbI3器件扩展了50meV,J sc达到26mA/cm2,PCE达到22.8%[84]㊂2023年,该团队在亲水性的([2-(3,6-dimethoxy-9H-carbazol-9-yl)ethyl]phosphonic acid,MeO-2PACz)单分子层表面生长FA0.6MA0.4PbI3钙钛矿单晶薄膜,与PTAA上生长的单晶薄膜相比,MeO-2PACz有效提高了钙钛矿单晶薄膜与衬底的机械粘附力,PCE达到创纪录的23.1%[85]㊂伴随着钙钛矿单晶薄膜生长技术的更新和迭代,钙钛矿单晶薄膜太阳能电池的器件性能有望超越钙钛矿多晶太阳能电池,在太阳能电池器件领域占据一席之地[86]㊂从钙钛矿材料结构角度出发,由金属阳离子和卤化物阴离子形成的强共价或离子键相互作用结合的钙钛矿八面体骨架结构,将为材料提供高的载流子迁移率骨架模型,据理论预测的迁移率最高可达1000cm2/(V㊃s);有机阳离子可以间接扭曲无机骨架,在分子尺度上影响材料的晶体结构和电学特性㊂因此,钙钛矿材料因其展现出较高的载流子迁移率,被认为是发展新一代半导体电子技术最理想的光电材料㊂基于钙钛矿单晶薄膜材料的场效应晶体管研究起步相对较晚,2018年,阿卜杜拉国王科技大学Amassian教授团队制备了底栅顶接触的钙钛矿单晶薄膜场效应晶体管器件,器件的沟道长度为10~150μm,如图5(e)所示[87]㊂该团队设计和制备了一系列基于MAPbCl3㊁MAPbBr3㊁MAPbI3单晶薄膜的场效应晶体管器件,测量和分析器件的转移和传输特性曲线,其空穴迁移率最高分别可达2.6㊁3.1㊁2.9cm2/(V㊃s),电子迁移率分别为2.2㊁1.8㊁1.1cm2/(V㊃s),且器件开关比分别可达2.4ˑ104㊁4.8ˑ103㊁6.7ˑ103㊂该系列场效应晶体管器件展现出良好的电学输运特性,为进一步推动钙钛矿单晶薄膜材料在集成电子器件领域的应用提供了良好的研究基础㊂钙钛矿发光二极管(perovskitelight emitting diodes,PeLED)近年来也发展迅速,自2014年英国剑桥大学的Friend教授课题组首次报道室温下PeLED器件以来,PeLED以其优异的光电性能㊁较低的器件成本,以及。
Invitrogen Quant-iT dsDNA Broad-Range Assay - 手册说明
For Research Use Only. Not for use in diagnostic procedures.Table 1.Contents and storageQuant-iT ™ dsDNA Broad-Range Assay KitCatalog no. Q33130IntroductionThe Quant-iT ™ dsDNA Broad-Range Assay Kit makes DNA quantitation easy and accurate. The kit provides concentrated assay reagent, dilution buffer, and pre-diluted DNA standards. Simply dilute the reagent 1:200, load 200 μL into the wells of amicroplate, add 1–20 μL sample volumes, mix, then read the fluorescence. The assay is highly selective for double-stranded DNA over RNA, and in the range of 2–1000 ng, the fluorescence signal is linear with DNA (Figure 2, page 2). The assay is performed at room temperature, and the signal is stable for 3 hours. Common contaminants, such as salts, solvents, detergents, or protein are well tolerated in the assay.In addition to the Quant-iT ™ dsDNA Broad-Range Assay Kit described here, we also offer the Quant-iT ™ dsDNA High-Sensitivity Assay Kit (Cat. no. Q33120). The Quant-iT ™ dsDNA High-Sensitivity Kit is designed for assaying samples containing 0.2–100 ng of DNA.If you would like to use this kit with the Qubit ® fluorometer, we have includedinstructions under Using the Quant-iT ™ dsDNA Broad-Range Assay Kit with the Qubit ® Fluorometer .Before You BeginHandling the Quant-iT ™ reagentWe must caution that no data are available addressing the mutagenicity or toxicity of the Quant-iT ™ dsDNA BR reagent. This reagent is known to bind nucleic acid and is provided as a solution in DMSO; treat the reagent with the same safety precautions as all other potential mutagens and dispose of the dye in accordance with local regulations.Remove the Quant-iT ™ dsDNA Broad-Range Assay Kit from storage and allow thecomponents to equilibrate to room temperature. During all steps, protect the Quant-iT ™ dsDNA BR reagent concentrate and the working solution from light as much as possible.Figure 2. DNA selectivity and sensitivity of the Quant-iT ™ dsDNA BR assay. Triplicate 10 µL samples of λ DNA ( ), E. coli rRNA ( ), or a 1:1 mixture of DNA and RNA ( ) were assayed in the Quant-iT ™ dsDNA BR assay. Fluorescence was measured at 485/530 nm and plotted versus the mass of nucleic acid for the DNA alone or RNA alone, or versus the mass of the DNA component in the 1:1 mixture. The variation (CV) of replicate DNA determinations was ≤3%. The inset, a separate experiment with octuplicate determinations, showsthe sensitivity of the assay for DNA. Background fluorescence has not been subtracted.Figure 1. Excitation and emission maxima for the Quant-iT ™dsDNA BR reagent bound to DNA.Using the Quant-iT ™ dsDNA Broad-Range Assay Kit with a Fluorescence Microplate ReaderThis protocol describes the use of the Quant-iT ™ dsDNA Broad-Range Assay Kit with a fluorescence microplate reader equipped with excitation and emission filters appropriate for fluorescein or Alexa Fluor ® 488 dye. Some contaminating substances may interfere with the assay. See Conatminating substances, page 7, for moreinformation. For an overview of this procedure, see Figure 3, below.Add Samples and Mix Well Add Quant-iT ™ standards (10 µL)and unknown samples (1–20 µL)Read PlateLoad Microplate with Working SolutionQuant-iT ™ reagentBufferFigure 3. The Quant-iT ™ dsDNA Broad-Range assay.1.1 Make a working solution by diluting Quant-iT ™ dsDNA BR reagent 1:200 in Quant-iT ™dsDNA BR buffer. For example, for ~100 assays put 100 μL of Quant-iT ™ dsDNA BR reagent (Component A) and 20 mL of Quant-iT ™ dsDNA BR buffer (Component B) in a disposable plastic container and mix well. Do not use glass containers. Do not use buffers other than the Quant-iT ™ dsDNA BR buffer to make the working solution.1.2 Load 200 μL of the working solution into each microplate well. Diluted Quant-iT ™dsDNA BR reagent is stable for at least 3 hours at room temperature, protected from light. 1.3 Add 10 μL of each λ DNA standard (Component C) to separate wells and mix well. Takecare not to introduce nucleases into the tubes of DNA standard as you remove aliquots for the assay. Duplicates or triplicates of the standards are recommended. 1.4 Add 1–20 μL of each unknown DNA sample to separate wells and mix well. Duplicatesor triplicates of the unknown samples are recommended. Some contaminating substances may interfere with the assay, see Contaminating substances , page 7. 1.5 Measure the fluorescence using a microplate reader (excitation/emission maxima are510/527 nm; see Figure 1, page 2). Standard fluorescein wavelengths (excitation/emission at ~480/530 nm) are appropriate for this dye. The fluorescence signal is stable for 3 hours at room temperature. 1.6 Use a standard curve to determine the DNA amounts. For the λ DNA standards, plotamount vs. fluorescence, and fit a straight line to the data points.Data analysis considerations –standard curves and extendedranges The fluorescence of the Quant-iT™ dsDNA BR reagent bound to dsDNA is extremelylinear from 0–1000 ng. For best results at the low end of the standard curve, the lineshould be forced through the background point (or through zero, if backgroundhas been subtracted). When 10 μL volumes of the standards are used, the lowestDNA-containing standard represents 50 ng of DNA; nevertheless, highly accuratedeterminations of DNA down to 2 ng are attained using the standard curve as describedabove.To assess the reliability of the assay in the low range, use smaller volumes of thestandards; for example, 2 μL volumes for a standard curve ranging from 0–200 ng(Figure 4A, below). Alternatively, dilute the standards in buffer for an even tighterrange (Figure 4A, inset). During development of the Quant-iT™ dsDNA BR assay, wewere able to detect 0.5 ng of λ DNA under ideal experimental circumstances (usingcalibrated pipettors, octuplicate determinations, the best microplate readers, andZ-factor1 analysis). Your results may vary.If desired, the utility of the Quant-iT™ dsDNA BR assay can be extended beyond1000 ng, up to 2000 ng (Figure 4B). For standards in this range, use 20 μL volumes of theprovided standards. Note that the standard curve may not be linear in the range1600–2000 ng.Figure 4. Extended ranges for the Quant-iT™ dsDNA BR assay. Triplicate 2 µL (Panel A) or 20 µL samples(Panel B) of λ DNA ( ), E. coli rRNA ( ), or a 1:1 mixture of DNA and RNA ( ) were assayed in the Quant-iT™dsDNA BR assay. Fluorescence was measured at 485/530 nm and plotted versus the mass of nucleic acidfor the DNA alone or RNA alone, or versus the mass of the DNA component in the 1:1 mixture. The inset(Panel A), a separate experiment with octuplicate determinations, shows the sensitivity of the assay forDNA. Background fluorescence has not been subtracted.Using the Quant-iT ™ dsDNA Broad-Range Assay Kit with the Qubit ® FluorometerThe Quant-iT ™ dsDNA BR Assay Kit can easily be adapted for use with the Qubit ® fluorometer. The protocol below is abbreviated from the Qubit ® fluorometer userguide, which is available at /qubit . Although a step-by-step protocol and critical assay parameters are given here, more detail is available in the Qubit ® fluorometer user guide and you are encouraged to familiarize yourself with this manual before you begin your assay. See Figure 5, below, for an overview of the procedure.Figure 5. Overview for using the Quant-iT ™ dsDNA BR assay in the Qubit ® fluorometer .IMPORTANT! Ensure all assay reagents are at room temperature before you begin. Use only thin-wall, clear 0.5 mL PCR tubes. Acceptable tubes include Qubit ® assay tubes (500 tubes, Cat. no. Q32856) or Axygen ® PCR-05-C tubes (VWR, part no. 10011-830).2.1 Label the lids of the assay tubes* you will need for the standards and user samples.Note: The Quant-iT ™ dsDNA BR Assay Kit requires two standards for calibration.Prepare a dilution of the 0 ng/µL λ dsDNA BR standard from the Component C set to generate Standard #1, and prepare a dilution of the 100 ng/µL λ dsDNA BR standard from the Component C set to generate Standard #2 (see step 2.3 below).2.2 Make the Quant-iT ™ dsDNA BR working solution by diluting the Quant-iT ™ dsDNA BRreagent 1:200 in Quant-iT ™ buffer. 2.3Prepare assay tubes according to Table 2 below.* where n = number of standards plus number of samplesFinal volume is 200 µLFinal volume is 200 µLVortex all assay tubes for 2–3 secondsIncubate at room temperature for 2 minutesRead tubes in the Qubit ® fluorometer2.5 Incubate the tubes for 2 minutes at room temperature.2.6 Calibrate the Qubit ® fluorometer using Standard #1 and Standard #2. 2.7 Read the user samples in the Qubit ® fluorometer.2.8 For Qubit ® 2.0 Fluorometer users: Multiply the readout from the Qubit ® 2.0 Fluorometerby the value given by the dilution factor (see the Qubit ® 2.0 Fluorometer user guide) to determine the concentration of your original sample. Alternatively, choose Calculate Sample Concentration to have the Qubit ® 2.0 Fluorometer perform this multiplication for you. For more information, refer to the Qubit ® 2.0 Fluorometer user guide.Note: The Qubit ® 3.0 Fluorometer performs this calculation automatically.Appendix: Critical Assay ParametersAssay temperatureThe Quant-iT ™ dsDNA BR assay for the Qubit ® fluorometer delivers optimal performance when all solutions are at room temperature. The Quant-iT ™ assays were designed to be performed at room temperature, as temperature fluctuations can influence the accuracy of the assay. To minimize temperature fluctuations, store the Quant-iT ™ dsDNA BR reagent and the Quant-iT ™ dsDNA BR buffer at room temperature and insert all assay tubes into the Qubit ® fluorometer only for as much time as it takes for the instrument to measure the fluorescence, as the Qubit ® fluorometer can raise the temperature of the assay solution significantly, even over a period of a few minutes. Do not hold the assay tubes in your hand before reading, as this will warm the solution and result in a low reading.Incubation timeIn order to allow the Quant-iT ™ dsDNA BR assay to reach maximum fluorescence, incubate the assay tubes for 2 minutes after mixing the sample or standard with the working solution. After this incubation period, the fluorescence signal is stable for3 hours at room temperature.2.4 Vortex all tubes for 2–3 seconds.Table 2. Tube setup.Photobleaching of theQuant-iT™ reagent The Quant-iT™ dsDNA BR reagent exhibits high photostability in the Qubit®fluorometer, showing <0.3% drop in fluorescence after 9 readings and <2.5% drop influorescence after 40 readings. It is important to remember, however, that if the assaytube remains in the Qubit® fluorometer for multiple readings, a temporary reductionin fluorescence will be observed as the solution increases in temperature. Note thatthe temperature inside the Qubit® Fluorometer may be as much as 3°C above roomtemperature after 1 hour. For this reason, if you want to perform multiple readings ofa single tube, you should remove the tube from the instrument and let it equilibrate toroom temperature for 30 seconds before taking another reading.Assay tubes to use with theQubit® Fluorometer Use only thin-wall, clear 0.5 mL PCR tubes with the Qubit® Fluorometer. Acceptabletubes include Qubit® assay tubes (Cat. no. Q32856, 500 tubes) or Axygen® PCR-05-C tubes(VWR, part number 10011-830). The assay volume must be 200 µL for an accurate read.Calibrating the Qubit®Fluorometer When quantifying your samples using the Qubit® fluorometer, you have the choice tocalibrate the instrument using freshly prepared calibration solutions or to apply thevalues from a previously run calibration. Using the Quant-iT™ dsDNA Broad-Range AssayKit with the Qubit® Fluorometer, page 5, describes the preparation of fresh calibrationstandards. Consult the instruction manual for the Qubit® fluorometer for guidance onchoosing a calibration mode.Contaminating substances A number of common contaminants have been tested in the Quant-iT™ dsDNA BR assay,and most are well tolerated (Table 3, below). For untested contaminating substances andin general, the standards should be assayed under the same conditions as the unknownsfor highest accuracy. For example, if the experimental samples are in an unusual bufferand if 10 µL volumes of these samples are used, then add 10 µL volumes of the unusualbuffer (lacking DNA) to the assays of the standards.Table 3. Effect of Contaminants in the Quant-iT™ dsDNA Broad-Range Assay. *Purchaser NotificationThese high-quality reagents and materials must be used by, or directl y under the super v ision of, a tech n ically qualified individual experienced in handling potentially hazardous chemicals. Read the Safety Data Sheet provided for each product; other regulatory considerations may apply.Obtaining SupportFor the latest services and support information for all locations, go to .At the website, you can:• Access worldwide telephone and fax numbers to contact Technical Support and Sales facilities • Search through frequently asked questions (FAQs)• Submit a question directly to Technical Support (************************)• Search for user documents, SDSs, vector maps and sequences, application notes, formulations, handbooks, certificates of analysis, citations, and other product support documents• Obtain information about customer training • Download software updates and patchesSDSSafety Data Sheets (SDSs) are available at /sds .Certificate of AnalysisThe Certificate of Analysis provides detailed quality control and product qualification information for each product. Certificates of Analysis are available on our website. Go to /support and search for the Certificate of Analysis by product lot number, which is printed on the product packaging (tube, pouch, or box).Limited Product WarrantyLife Technologies Corporation and/or its affiliate(s) warrant their products as set forth in the Life Technologies’ General Terms and Conditions of Sale found on Life Technologies’ website at /termsandconditions . If you have any questions, please contact Life Technologies at /support .DisclaimerLIFE TECHNOLOGIES CORPORATION AND/OR ITS AFFILIATE(S) DISCLAIM ALL WARRANTIES WITH RESPECT TO THIS DOCUMENT, EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO THOSE OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT. TO THE EXTENT ALLOWED BY LAW, IN NO EVENT SHALL LIFE TECHNOLOGIES AND/OR ITS AFFILIATE(S) BE LIABLE, WHETHER IN CONTRACT, TORT, WARRANTY, OR UNDER ANY STATUTE OR ON ANY OTHER BASIS FOR SPECIAL, INCIDENTAL, INDIRECT, PUNITIVE, MULTIPLE OR CONSEQUENTIAL DAMAGES IN CONNECTION WITH OR ARISING FROM THIS DOCUMENT, INCLUDING BUT NOT LIMITED TO THE USE THEREOF.Important Licensing InformationThis product may be covered by one or more Limited Use Label Licenses. By use of this product, you accept the terms and conditions of all applicable Limited Use Label Licenses.All trademarks are the property of Thermo Fisher Scientific and its subsidiaries, unless otherwise specified. NanoDrop is a registered trademark of NanoDrop Technologies, LLC.Triton is a registered trademark of Union Carbide Corporation.Axygen is a registered trademark of Axygen, Inc.©2015 Thermo Fisher Scientific Inc. All rights reserved.16 February 2015Reference1. J Biomol Screen 4, 67-73 (1999).Product List Current prices may be obtained from our website or from our Customer Service Department.Cat. no. Product Name Unit SizeQ33130 Quant-iT™ dsDNA Assay Kit, Broad Range, 1000 assays *2–1000 ng*.............................................. 1 kit Related products Q33120 Quant-iT™ dsDNA Assay Kit, High Sensitivity, 1000 assays *0.2–100 ng* ........................................... 1 kit Q10213 Quant-iT™ RNA Assay Kit, Broad Range, 1000 assays *20–1000 ng*............................................... 1 kit Q33140 Quant-iT™ RNA Assay Kit, 1000 assays *5–100 ng*............................................................. 1 kit Q32882 Quant-iT™ microRNA Assay Kit, 1000 assays *5–500 ng*........................................................ 1 kit Q33210 Quant-iT™ Protein Assay Kit, 1000 assays *0.25–5 μg*.......................................................... 1 kit O11492 Quant-iT™ OliGreen ® ssDNA Assay Kit *2000 assays* ..........................................................1 kit。
硅纳米粒子的功能化及生物分析应用
第60卷第3期2021年5月Vol.60No.3May 2021中山大学学报（自然科学版）ACTASCIENTIARUM NATURALIUM UNIVERSITATISSUNYATSENI硅纳米粒子的功能化及生物分析应用*李春荣1，3，邹小勇1，戴宗21.中山大学化学学院，广东广州5102752.中山大学生物医学工程学院，广东深圳5181073.黔南民族医学高等专科学校，贵州都匀558013摘要：硅纳米粒子作为一类新兴的荧光纳米材料在生物传感研究方面有许多优势。
近年来，开展功能化硅纳米粒子修饰在生物传感器、生化分析、荧光探针等方面受到科研工作者的广泛关注。
本综述对硅纳米粒子的功能化修饰技术，及其在荧光检测、生物传感、成像分析等领域的研究进展进行了总结和评述，并对硅纳米粒子的功能化发展前景及应用进行了展望。
关键词：硅纳米粒子；细胞成像；功能化修饰；生物传感；荧光检测中图分类号：O657文献标志码：A文章编号：0529-6579（2021）03-0001-11Founctional silicon nanoparticles and bioanalitical applicationLI Chunrong 1，3，ZOU Xiaoyong 1，DAI Zong 21.School of Chemistry ，Sun Yat -sen University ，Guangzhou 510275，China2.School of Biomedical Engineering ，Sun Yat -sen University ，Shenzhen 518107，China3.Qiannan Medical College for Nationalities ，Duyun 558013，ChinaAbstract ：As a newly emerging nanomaterial ，silicon nanoparticle possesses many advantages in the ap⁃plication of biosensor.In recent years ，silicon nanoparticles have been received widespread attention in biosensor ，bioanalytical ，and fluorescence probe.Herein ，the functional modification ，and application in fluorescence detection ，biosensor ，and imaging analytical of silicon nanoparticles were reviewed.Moreover ，the future functional modification developments and application of silicon nanoparticles are al⁃so discussed.Key words ：silicon nanoparticles ；cell imaging ；function modification ；biosensor ；fluorescence detection 硅是地壳中含量第二大元素，为各种硅相关应用材料提供了丰富而低成本的资源支持。
量子点的水相合成及表征
ｓｙｎｔｈｅｓｉｓ ｏｆ ＣｄＴｅ ｑｕａｎｔｕｍ ｄｏｔｓ，ｆｌｕｏｒｅｓｃｅｎｃｅ ｅｘｃｉｔａｔｉｏｎ ｓｐｅｃｔｒａ ｏｆ ｂｒｏａｄ，ｓｈａｒｐ
ｅｍｉｓｓｉｏｎ ｓｐｅｃｔｒａ，ｈｉ曲ｑｕａｎｔｕｍ ｙｉｅｌｄ，ｆｌｕｏｒｅｓｃｅｎｃｅ ｉｎｔｅｎｓｉｔｙ，ａｎｄ ｔｈｅ ｉｍｐｌｅｍｅｎｔａｔｉｏｎ ｂｙ ｃｈａｎｇｉｎｇ ｔｈｅ ｒｅａｃｔｉｏｎ ｔｉｍｅ ａｎｄ ｔｈｅ ｒａｔｉｏ ｏｆ ｒｅａｃｔａｎｔｓ ｔｏ ｔｕｎｉｎｇ ｔｈｅ ｓｉｚｅ ｏｆ ｑｕａｎｔｕｍ
ｑｕａｎｔｕｍ ｄｏｔｓ，ｆｌｕｏｒｅｓｃｅｎｃｅ ａｂｓｏｒｐｔｉｏｎ ａｎｄ ｅｍｉｓｓｉｏｎ ｓｐｅｃｔｒａ，ａｓ ｗｅｌｌ ａｓ ｔｈｅ ｉｍｐａｃｔ ｏｆ
ｑｕａｎｔｕｍ ｙｉｅｌｄ．Ｕｓｉｎｇ ＵＶ ｓｐｅｃｔｒｏｐｈｏｔｏｍｅｔｅｒ，ｆｌｕｏｒｅｓｃｅｎｃｅ ｓｐｅｃｔｒｏｐｈｏｔｏｍｅｔｅｒ， ｔｒａｎｓｍｉｓｓｉｏｎ ｅｌｅｃｔｒｏｎ ｍｉｃｒｏｓｃｏｐｙ，ｍｉｃｒｏｐｌａｔｅ ｒｅａｄｅｒ，ｐａｒｔｉｃｌｅ ｓｉｚｅ ａｎａｌｙｚｅｒ， ｆｌｕｏｒｅｓｃｅｎｃｅ ｃｏｎｆｏｃａｌ ｍｉｃｒｏｓｃｏｐｙ， ｆｌｕｏｒｅｓｃｅｎｃｅ ｃｏｎｆｏｃａｌ ｓｃａｎｎｅｒ ｍｅａｎｓ ｆｏｒ ｔｈｅ ｓｙｎｔｈｅｓｉｓ ｏｆ ｑｕａｎｔｕｍ ｄｏｔｓ ｗｅｒｅ ｃｈａｒａｃｔｅｒｉｚｅｄ．
讨论与结论
１．在有氧条件下，以巯基乙酸为修饰剂，在水溶液中合成的ＣｄＳｅ／ＳｉＯ：量子 点，粒径均匀，均为球形，随反应时间以及包被时间不同，粒径随之改变，荧光 发射光谱也随之改变，实现了通过反应时间与包被时间对量子点尺寸的调谐作用。
２．在无氧条件下，以巯基乙酸为修饰剂，在水溶液中合成的ＣｄＴｅ量子点，荧 光激发光谱广，发射光谱尖锐，量子产率高，荧光强度大，并实现了通过改变反 应时间与反应物比例来调谐量子点的尺寸。
Michael-quirk-半导体制造技术-第五章-半导体制造中的化学品
30 20
40 50
10 00
70 80
High
High
temperature pressure
30 20
40 50
10 0
70 80
Moveable piston
Volume increase
Semiconductor Manufacturing Technology
by Michael Quirk and Julian Serda
Properties of Materials
• Temperature • Pressure and Vacuum • Condensation • Vapor Pressure • Sublimation and
Deposition • Density • Surface Tension • Thermal Expansion • Stress
by Michael Quirk and Julian Serda
© 2001 by Prentice Hall
Objectives
After studying the material in this chapter, you will be able to:
1. Identify and discuss the four states of matter.
Sublimation
Dry ice (CO2)
Semiconductor Manufacturing Technology
by Michael Quirk and Julian Serda
Figure 5.7
© 2001 by Prentice Hall
Deposition
advanced optical materials分区
Advanced Optical MaterialsIntroductionAdvanced optical materials are a class of materials that possess unique optical properties and are engineered to enhance light-matter interactions. These materials have revolutionized various fields such as photonics, optoelectronics, and nanotechnology. In this article, we will explore the different types of advanced optical materials, their applications, and the future prospects of this exciting field.Types of Advanced Optical MaterialsPhotonic CrystalsPhotonic crystals are periodic structures that can manipulate the propagation of light. They consist of a periodic arrangement ofdielectric or metallic components with alternating refractive indices. These structures can control the flow of light by creating energy bandgaps, which prohibit certain wavelengths from propagating through the material. Photonic crystals find applications in optical communication, sensing, and solar cells.MetamaterialsMetamaterials are artificially engineered materials that exhibit properties not found in nature. They are composed of subwavelength-sized building blocks arranged in a periodic or random manner. Metamaterials can manipulate electromagnetic waves by achieving negative refractive index, perfect absorption, and cloaking effects. These unique properties have led to applications in invisibility cloaks, super lenses, and efficient light harvesting.Plasmonic MaterialsPlasmonic materials exploit the interaction between light and free electrons at metal-dielectric interfaces to confine light at nanoscale dimensions. This confinement results in enhanced electromagnetic fields known as surface plasmon resonances. Plasmonic materials have diverse applications such as biosensing, photothermal therapy, and enhanced solar cells.Quantum DotsQuantum dots are nanoscale semiconductor crystals with unique optical properties due to quantum confinement effects. Their size-tunable bandgap enables them to emit different colors of light depending ontheir size. Quantum dots find applications in display technologies (e.g., QLED TVs), biological imaging, and photovoltaics.Organic Optoelectronic MaterialsOrganic optoelectronic materials are based on organic compounds that exhibit electrical conductivity and optical properties. These materials are lightweight, flexible, and can be processed at low cost. They find applications in organic light-emitting diodes (OLEDs), organic photovoltaics (OPVs), and organic field-effect transistors (OFETs).Applications of Advanced Optical MaterialsInformation TechnologyAdvanced optical materials play a crucial role in information technology. Photonic crystals enable the miniaturization of optical devices, leading to faster and more efficient data transmission. Metamaterials offer possibilities for creating ultra-compact photonic integrated circuits. Plasmonic materials enable the development of high-density data storage devices.Energy HarvestingAdvanced optical materials have revolutionized energy harvesting technologies. Quantum dots and organic optoelectronic materials are used in next-generation solar cells to enhance light absorption and efficiency. Plasmonic nanoparticles can concentrate light in solar cells, increasing their power output. These advancements contribute to the development of sustainable energy sources.Sensing and ImagingThe unique optical properties of advanced optical materials make them ideal for sensing and imaging applications. Quantum dots are used as fluorescent probes in biological imaging due to their bright emissionand excellent photostability. Metamaterial-based sensors offer high sensitivity for detecting minute changes in refractive index ormolecular interactions.Biomedical ApplicationsAdvanced optical materials have significant implications in biomedical research and healthcare. Plasmonic nanomaterials enable targeted drug delivery, photothermal therapy, and bioimaging with high spatial resolution. Organic optoelectronic materials find applications in wearable biosensors, smart bandages, and flexible medical devices.Future ProspectsThe field of advanced optical materials is rapidly evolving with continuous advancements being made in material synthesis, characterization techniques, and device fabrication processes. Thefuture prospects of this field are promising, with potential breakthroughs in areas such as:1.Quantum Optics: Integration of advanced optical materials withquantum technologies could lead to the development of quantumcomputers, secure communication networks, and ultra-precisesensors.2.Flexible and Wearable Electronics: Organic optoelectronicmaterials offer the potential for flexible and wearable electronic devices, such as flexible displays, electronic textiles, andimplantable medical devices.3.Optical Computing: Photonic crystals and metamaterials may pavethe way for all-optical computing, where photons replace electrons for faster and more energy-efficient data processing.4.Enhanced Optoelectronic Devices: Continued research on advancedoptical materials will lead to improved performance and efficiency of optoelectronic devices such as solar cells, LEDs, lasers, andphotodetectors.In conclusion, advanced optical materials have opened up newpossibilities in various fields by enabling unprecedented control over light-matter interactions. The ongoing research and development in this field promise exciting advancements in information technology, energy harvesting, sensing and imaging, as well as biomedical applications. The future looks bright for advanced optical materials as they continue to revolutionize technology and shape our world.。