溶胶–凝胶法制备ATO-SiO_2抗静电复合薄膜的特性研究

采用两步溶胶–凝胶法制备出 ATO(掺锑氧化锡)-SiO_2复合抗静电薄膜。通过 DTA-TG、XRD、SEM 对 薄膜的结构和形貌进行了表征,结果表明:抗静电复合薄膜表面均匀致密。薄膜中 SiO_2为无定形结构,ATO 的衍射峰 与 SnO_2一致。研究了 SnO_2的含量对薄膜导电性能、结合强度和透过率的影响,发现随 SnO_2含量增加 ?(SnO_2/ SiO_2)从 5 至 12.5,薄膜的表面电阻降低(从 1010ù/□降低到 108ù/□),薄膜的结合强度下降,薄膜的透过率降低(从 89.0%降至 84.2%),结合三方面性能,得出最佳 SnO_2的配比为:?(SnO_2/ SiO_2)=10。     

(Cd,Co,Nb)掺杂的SnO2压敏材料的电学性质

研究了Cd对(Co，Nb)掺杂SnO2压敏材料电学性质的影响。组分为97．65％SnO2 O．75％Co2O3 0．10％Nb2O5 1．50％CdO的压敏电阻具有最大非线性系数(a=22．2)和最高的势垒(ψB=0．761eV)．当CdO的摩尔分数从0增加到3％时，(Co，Nb)掺杂SnO2压敏电阻的击穿电压从366V／mm增大到556V／mm，1kHz时的相对介电常数从1429减小到1108。晶界势垒高度测量揭示，SnO2的晶粒尺寸的减小是击穿电压增高和介电常数减小的主要原因。对Cd掺杂量增加引起SnO2晶粒减小的根源进行了解释。     

Charge‐Generating Mode Control in High‐Performance Transparent Flexible Piezoelectric Nanogenerators

In this work, we demonstrate the mode transition of charge generation between direct‐current (DC) and alternating‐current (AC) from transparent flexible (TF) piezoelectric nanogenerators (NGs), which is dependent solely on the morphology of zinc oxide (ZnO) nanorods without any use of an AC/DC converter. Tilted ZnO nanorods grown on a relatively low‐density seed layer generate DC‐type piezoelectric charges under a pushing load, whereas vertically aligned ZnO nanorods on a relatively high‐density seed layer create AC‐type charge generation. The mechanism for the geometry‐induced mode transition is proposed and characterized. We also examine the output performance of TF‐NGs which employ an indium zinc tin oxide (IZTO) film as a TF electrode. It is demonstrated that an IZTO film has improved electrical, optical, and mechanical properties, in comparison with an indium tin oxide (ITO) film. Enhanced output charge generation is observed from IZTO‐based TF‐NGs when TF‐NGs composed of only ITO electrodes are compared. This is attributed to the higher Schottky barrier and the lower series resistance of the IZTO‐based TF‐NGs. Thus, by using IZTO, we can expect TF‐NGs with superior mechanical durability and power generating performance.     

直流磁控溅射ITO薄膜的正交试验分析

利用直流磁控溅射系统制备ITO薄膜,采用正交试验表格L32(48)安排试验.测试了薄膜的方阻和透过率,分析了8个工艺参数对薄膜电光特性的影响,其中沉积气压、氩氧流量比和退火温度的影响最大.分析得到优化工艺参数为:沉积气压2×133.322 4 mPa、氩氧流量比16∶0.5、退火温度427 ℃、靶基间距15、退火时间1 h、溅射功率300 W、退火氛围为真空、沉积温度227 ℃.在此工艺参数下制备的ITO薄膜方阻为17 Ω/□,电阻率为1.87×10-4Ω·cm,在可见光区域平均透过率为85.13%.     

Inhibition of Whisker Growth on the Surface of Sn-3Ag-0.5Cu-0.5Ce Solder Alloyed with Zn

Solder alloys doped with rare-earth elements have been reported to show many beneficial effects. However, tin whiskers have been observed to appear on the surface of Sn-3Ag-0.5Cu-0.5Ce solder joints after air exposure for short periods. Such a phenomenon of abnormal whisker growth may significantly degrade the reliability of electronic packaging. The present study shows that the tin whiskers can be prevented by the addition of 0.5 wt.% Zn into a Sn-3Ag-0.5Cu-0.5Ce solder. The inhibition effect on the whisker growth is correlated to the refining of (Ce_0.9Zn_0.1)Sn₃ intermetallics in this Sn-3Ag-0.5Cu-0.5Ce-0.5Zn alloy.     

超细铜粉的化学镀锡及其抗氧化性能研究

以水合肼还原法制备出平均粒径约1μm的超细铜粉,并对其进行化学镀锡。研究了镀锡层对复合粉末微观形貌及抗氧化性能的影响。结果表明:镀覆质量分数50%的锡后,复合粉末平均粒径有所减小,但在空气中的氧化起始温度从120℃提高到220℃,与镀银层相比,镀锡层在较低温度区间对铜粉抗氧化具有优势。     

挠性电路板引脚嵌合部无铅镀层的锡须生长

以民用挠性印制电路板(FPC)引脚和连接器嵌合部无铅镀层为对象,通过研究引脚上的Ni/Sn无铅镀层的显微形貌和锡须尺寸,探讨了Ni/Sn无铅镀层的长期可靠性。结果表明,在25℃,RH为45%～55%的条件下,挠性印制电路板引脚和连接器嵌合部无铅镀层上生长的锡须呈现针状、柱状等多种不同的显微形貌,其中大部分是针状锡须,少量针状锡须的长度已超过了50μm临界值,很可能因锡须桥接引起电流泄漏和短路,对FPC互连可靠性产生威胁。抑制少量超长的针状晶须的生长,是防止风险的关键。     

多层交替结构Ga2O3/ITO深紫外透明导电膜

Ga2O3/ITO alternating multilayer films were deposited on quartz glass substrates by magnetron sputtering.The effect of the multi-period on the structural,optical and electrical properties of Ga2O3/ITO alternating multilayer films was investigated by an X-ray diffractometer,a double beam spectrophotometer and the Hall system,respectively.A low sheet resistance of 225.5Ω/□ and a high transmittance of more than 62.9% at a 300 nm wavelength were obtained for the two-period alternating multilayer film with a thickness of 72 nm.