柔性印制电子用铜基无颗粒型导电墨水的研究进展

作为制作导电图案的基础材料,导电墨水是柔性印制电子技术发展的关键.铜无颗粒型导电墨水材料凭借其制备灵活、稳定性好和烧结温度低等优势而备受关注.此类墨水有望解决铜纳米墨水在制备、储存和图案化过程中存在的聚集和氧化问题.以铜无颗粒型导电墨水为主要内容进行综述,对所涉及的铜前驱体材料的选择、墨水化方法、图案化方法和不同类型的...     

自还原体系银导电墨水的制备与低温印制导电图形的研究

总结了开发一种简便快捷的可印制在挠性基板上于低温条件实现烧结形成高导电性线路的自还原型银导电墨水的制备方法。该导电墨水通过混合二乙醇胺溶液和银氨溶液制备得到。印制在塑料基材上后,在75℃下固化形成导电线路。这是因为在碱性环境与高于50℃的温度下,二乙醇胺可分解生成甲醛并自发地与银氨溶液发生反应。随后还原出银原子并让其吸附在基材上形成银薄膜。用该方法印制得到的银线其导电率可达到金属银导电率的20％,通过继续改进可应用于各种印制电子技术中。     

纳米银导电墨水的制备及烧结北大核心

通过液相化学还原法制备了纳米银颗粒,纯化后通过X射线衍射（XRD）和能量色散谱（EDS）分析证明得到了结构完整、较为纯净的纳米银颗粒。将其制备为纳米银导电墨水,墨水的粒度分布窄、平均粒径约为25 nm、分散性好,表面张力为32.13 dyn/cm（1 dyn/cm=0.001 N/m）、黏度为4.66 mPa·s,符合喷墨打印对于墨水的要求。将墨水喷印在聚酰亚胺（PI）基材上,分别在125,150,175,200和225℃下烧结30 min,然后测量导电线路的电阻率,发现150℃下烧结电阻率为5.72×10-4Ω·cm,已满足电子电路印刷需求,随着烧结温度的提升,电阻率也不断下降,225℃下烧结,电阻率达1.53×10-5Ω·cm;同时对其烧结过程进行了分析,探究了导电线路中不导电组分的挥发及纳米银的熔融程度对电阻率的影响。     

高导电三维打印石墨烯墨水的制备与性能研究

当前利用三维打印技术(3DP)制备石墨烯器件时,通常采用的化学还原法由于常使用剧毒的强还原剂,生产过程危险性大,污染性强。相较而言,热还原法制作工艺简单,参数可控性强,更适合用于通过3DP技术制备高导电集成电路器件。采用还原氧化法来制备石墨烯,通过Hummers法氧化石墨单质合成氧化石墨烯(GO),以GO作为基底材料,加入一定比例的黏结剂、分散剂等添加剂来配制可用于3DP的GO墨水。选择3DP中简单可控的直写成型(DIW)工艺来打印导电线路,并将导线置于氩气环境下的管式炉中,分别在200,500和800℃的温度中进行烧结还原,经过800℃热还原的还原氧化石墨烯(rGO),其方阻可降低至200 mΩ/以下。试验测试分析表明,配制的GO墨水可用于三维打印导电线路,且经烧结热还原后得到高电导率的rGO电子器件。     

喷墨印刷沉积的PEDOT/PSS薄膜导电性能

利用压电喷墨印刷技术沉积了PEDOT/PSS有机导电薄膜,研究了退火温度和乙二醇掺杂对薄膜导电性能的影响。实验结果表明:未退火和退火温度为120,140,160℃时,薄膜表面平均粗糙度分别为8.15,4.10,3.36,2.66nm;乙二醇掺杂使导电激活能由未掺杂时的0.096eV减小为0.046eV;电导激活能减小表明PEDOT分子链从低电导率的卷曲构象向高电导率的伸展构象转变;此外,乙二醇掺杂促使PSS与PE-DOT/PSS分离,使团聚的PEDOT/PSS颗粒变小从而分散更均匀,降低了表面粗糙度。     

RF磁控溅射制备AZO透明导电薄膜及其性能

室温下采用RF磁控溅射技术在石英衬底E制备了多晶ZnO:Al(AZO)透明导电薄膜,通过XRD,AFM,AES,Hall效应及透射光谱等测试研究了RF溅射功率、氩气压强对薄膜的结构、电学和光学性能的影响.分析表明:在最优条件下(溅射功率为250W,氩气压强为1.2Pa时),180nm AZO薄膜的电阻率为2.68×10-3 Ω·cm,可见光区平均透射率为90%,适合作为发光二极管和太阳能电池的透明电极.所制备的AZO薄膜具有c轴择优取向,晶粒问界中的O原子吸附是限制薄膜电学性能的主要因素.     

RF磁控溅射制备AZO透明导电薄膜及其性能

室温下采用RF磁控溅射技术在石英衬底上制备了多晶ZnO: Al (AZO）透明导电薄膜,通过XRD,AFM,AES,Hall效应及透射光谱等测试研究了RF溅射功率、氩气压强对薄膜的结构、电学和光学性能的影响. 分析表明:在最优条件下（溅射功率为250W,氩气压强为1.2Pa时）, 180nm AZO薄膜的电阻率为2.68E-3 Ω· cm,可见光区平均透射率为90%,适合作为发光二极管和太阳能电池的透明电极. 所制备的AZO薄膜具有c轴择优取向,晶粒间界中的O原子吸附是限制薄膜电学性能的主要因素.     

NZO透明导电薄膜的制备及其性能研究

室温下,采用直流磁控溅射法,在玻璃衬底上制备出Nb掺杂ZnO(NZO,ZnO:Nb)透明导电薄膜。研究了靶与衬底之间的距离对NZO薄膜结构、形貌、光学及电学性能的影响。实验结果表明,不同靶基距下制备的NZO薄膜均为c轴择优取向生长,(002)衍射峰的强度随着靶基距的减小而增大。靶基距增大时,薄膜表面逐步趋向平整光滑、均匀致密,薄膜的厚度逐渐减小。在靶基距为60mm时,制备的薄膜厚为355.4nm,电阻率具有最小值(6.04×10-4Ω.cm),在可见光区的平均透过率达到92.5%,其光学带隙为3.39eV。     

基于喷墨打印银基无颗粒油墨的柔性电极

柔性电极是柔性电子的基础组成部分,而低成本快速制备高性能柔性电极是柔性电子发展的基础问题之一。基于银基无颗粒银基油墨,利用低成本的家用喷墨打印机实现了柔性聚酰亚胺衬底上的导电电极的打印制备。经过热烧结处理后,得到了的柔性电极展示出优良导电性,良好的柔性弯曲特性和较强的附着力可作为柔性电路板实现良好的电连接,在此基础上实现了电容性柔性触摸按键。本文对制备低成本、易操作的柔性电路及柔性电子器件具有参考价值。     

基于微结构的银纳米线透明导电薄膜的光电性能北大核心

首先,采用光刻技术并结合湿法刻蚀工艺,在玻璃衬底上制备出蜂窝状分布的圆台阵列微结构,从占空比和反射、透射光线分布的角度分析其光学性能。然后,采用水热法制备银纳米线,并对样品进行X射线衍射（XRD）物相分析和扫描电子显微镜（SEM）微观形貌表征,得到平均直径为80 nm、长度为110μm、长径比大于1 000的超细长银纳米线。最后,通过浓硫酸和双氧水的混合溶液对微结构表面改性,并采用变速旋涂法将银纳米线与微结构完美嵌合,从而制备出基于玻璃衬底上圆台阵列微结构的银纳米线透明导电薄膜,其光电性能优良,测得其可见光透过率为85.97%、方块电阻平均值为23.1Ω/□。     

Synthesis of highly conductive cobalt thin films by LCVD at atmospheric pressure

We have deposited very low resistant Co films on SiO₂-coated Si substrates using UV pulsed laser pyrolytic decomposition of Co₂(CO)₈ with 355 nm laser radiation at atmospheric pressure. Facile decomposition of the precursors and the use of Ar curtain enable the deposition of relatively pure Co (with O less than 7% and negligible C) at the power of 1.11–3.33 W, and of pure Co at 6.67 W. The resistivity decreases from 58 to 19 µΩ-cm as the power increases from 2.22 to 3.33 W, showing inverse-linear dependence on grain size. In addition, further increase of the power to 6.67 W decreases the resistivity to 9 µΩ-cm, due to both the growth of large grains with negligible contaminants, and the adverse effect of surface roughness. The effects of oxygen contaminants on the resistivity can be minimal, because of its presence in the form of oxide. These low resistant fine metal lines deposited by a direct-writing laser chemical vapor deposition technique at atmospheric pressure have been reported for the first time.     

用纳米银棒和颗粒制备高导电性油墨

研制了一种高导电性油墨。首先,分别以乙二醇和N,N-二甲基甲酰胺为还原剂,还原硝酸银溶液得到纳米银棒和纳米银球形颗粒。用纳米银棒和纳米银球形颗粒混合银粉、双酚A环氧树脂/酚醛树脂、丁酮等其他助剂配制导电油墨。研究了不同固化温度、固化时间对所制油墨导电性能的影响。结果表明,在150℃固化20 min该油墨印刷的导电图形具有很致密的表面结构和丰富的三维导电网络,其体积电阻率达3.6 10–6.cm。     

AZO透明导电薄膜的结构与光电性能

采用射频溅射工艺制备了Zn1-xAlxO透明导电薄膜。通过XRD、UV透射和电学性能测试等分析手段,研究了Al浓度对薄膜的组织结构和光电性能的影响规律。结果表明:薄膜具有c轴择优取向,随着Al浓度的增加,(002)衍射峰向高角度移动,峰强度逐渐减弱,x(Al)为15%掺杂极限浓度。x(Al)为2%时,薄膜电阻率是3.4×10–4Ω.cm。随着掺杂量x(Al)从0增加到20%,薄膜的禁带宽度从3.34 eV增加到4.0 eV。     

The characterization of electrically conductive silver ink patterns on flexible substrates

Electrically conductive silver ink patterns were produced by the screen printing method. Paper, fabrics and plastics were used as the substrate materials. The electrical properties of the samples were characterized by sheet resistance measurement as a function of curing temperature and curing time. The mechanical properties of the samples were characterized by cross hatch adhesion test, bending test and tensile test. Depending on the process parameters and materials, the sheet resistance of the printed conductive patterns varied between 0.04 Ω/□ and 0.13 Ω/□. The curing temperature appeared to have a significant effect on the sheet resistance. In all cases sheet resistance decreased as a function of curing temperature. Adhesion between the substrates and the conductive patterns appeared to be good. The result of the bending test indicated that the resistivity of the silver ink patterns increased as a function of the bending cycle process. The results of the tensile and electrical tests showed that with the screen printing method it is possible to produce highly stretchable electrically conductive patterns for practical applications.     

Electrical properties of silver Schottky contacts to ZnO thin films

ZnO thin films are deposited on Al/Si substrates by the pulsed laser deposition （PLD） method. The XRD and SEM images of films are examined. Highly c-axis oriented ZnO thin films which have uniform compact surface morphology are fabricated. The size of surface grains is about 30 nm. The Schottky barrier ultraviolet detectors with silver Schottky contacts are made on ZnO thin films. The current-voltage characteristics are measured. The ideality contact factor between Ag and ZnO film is 1.22, while the barrier height is 0.908 e V. After annealing at 600 ℃ for 2h, the ideality factor is 1.18 and the barrier height is 0.988 eV. With the illumination of 325 nm wavelength UV-light, the photocurrent-to-dark current ratios before and after annealing are 140.4 and 138.4 biased at 5 V, respectively. The photocurrents increase more than two orders of magnitude over the dark currents.     

导电银浆的制备和性能研究

采用商用微米银片为导电相,玻璃粉为粘结剂,乙基纤维素、松油醇和曲拉通为有机载体制备了烧渗型银浆。利用扫描电子显微镜、方阻仪和百格测试法对烧结银浆的显微结构、导电性和附着力进行表征和研究。实验结果表明:烧结温度、玻璃粉含量和导电相的性质对银浆烧结后的显微结构、导电性和附着力均有较大影响。其中,烧结温度不仅对玻璃粉的熔化情况有影响,而且对烧结后的银浆中银片间的接触程度和与基材的润湿性等也有影响;玻璃粉的含量是影响烧结银浆的导电性和附着力的主要因素;微米银片中掺杂纳米银会导致烧结体中导电颗粒间的致密性下降,进而导致烧结后的银浆的导电性和附着力均下降。     

Analysis of electrically conductive silver ink on stretchable substrates under tensile load

Electrical conductors were printed by the screen printing method on stretchable PVC substrates and on fabrics. Polymer thick film silver ink was used as the conductive medium. The electrical performance and the structure of the ink film were investigated in unloaded conditions and under strain. In addition, the ink film morphology was examined. The goal of this study was to provide information for developing a strain sensor for large strain levels using the materials under investigation. An additional aim was to assist the integration of electronics into other structures. The results showed that strain sensitive structures can be made using the materials selected for this study and these materials provide an opportunity to develop strain sensors. The structures also tolerated large strain levels and thus they can be integrated into other materials which are exposed to strain.     

AZO透明导电薄膜的制备

采用射频磁控溅射法在玻璃衬底上制备了ZnO:Al(AZO)透明导电薄膜,并借助XRD、SEM等表征方法,研究了溅射功率和衬底温度对薄膜结构、表面形貌及光电特性的影响。结果表明,制备薄膜的最佳溅射功率和衬底温度分别为180 W、200℃,在此条件下制备的AZO薄膜具有明显的c轴(002)择优取向,其最低方块电阻为18/□,在可见光范围内的平均透光率超过91%,且透明导电性能优于目前平板显示器的要求,有望取代现在市场上的主流氧化铟锡(ITO)薄膜。     

磁控溅射AZO透明导电薄膜及其光电性能的研究

采用磁控溅射法在石英玻璃衬底上制备AZO薄膜。利用X射线衍射仪、原子力显微镜、四探针测试仪和透射光谱仪等手段研究了衬底温度对AZO薄膜结构、形貌、光电性能的影响。结果表明,所有的AZO薄膜均为纤锌矿结构且具有较好的c轴取向。薄膜表面平整,晶粒约为55.56 nm。随着衬底温度升高,薄膜电阻率先降低而后升高,当衬底温度为350℃时,电阻率最小,约为1.41×10–3?·cm,而且该薄膜具有较好的透光率,约为84%。     

水性导电油墨的制备及导电性能研究

以水性丙烯酸树脂为粘结剂,以水性石墨烯浆料、导电炭黑为导电剂,制备了一种新型水性导电油墨。分析了其导电机理,研究了不同影响因素对水性导电油墨导电性的变化规律。结果表明:当石墨烯和导电炭黑单独作为导电剂时,随着石墨烯含量或者导电炭黑含量的增加,体积电阻率减小;当石墨烯含量或者导电炭黑含量大于一定值后,体积电阻率有所回升。当石墨烯与导电炭黑的混合物作为导电剂时,制备的水性导电油墨比其单独作为导电剂的导电性更为优异。同时,水性导电油墨的体积电阻率随着丙烯酸树脂含量的增加而增大。