Electromigration Damage of Flexible Electronic Lines Printed With Ag Nanoparticle Ink
Electromigration Damage of Flexible Electronic Lines Printed With Ag Nanoparticle Ink
复制标题
DOI：
10.1115/1.4046849
复制
发表时间：
2020-09
影响因子：
1.6
通讯作者：
Daiki Saito;K. Sasagawa;T. Moriwaki;K. Fujisaki
中科院分区：
文献类型：
--
作者：
Daiki Saito;K. Sasagawa;T. Moriwaki;K. Fujisaki
柔性印刷电路（FPC）广泛用于电子设备，例如移动的装置和可穿戴传感器。这些电路中的导电线路使用纳米颗粒金属墨水和喷墨直写方法印刷。金属纳米颗粒墨水线的柔性和机械耐久性等物理特性已通过弯曲或拉伸测试进行评估。与此相反，这些线路的电气特性尚未得到充分评估，高密度电流下的故障机制尚未明确。当电子器件按比例缩小时，导线中的电流密度和焦耳热增加，并且电迁移（EM）损伤成为严重的问题。因此，减少电磁损伤对于提高器件可靠性是极其重要的。在这项研究中，银纳米粒子墨水线的故障分析进行了评估，使用电流负载测试和显微镜观察，以讨论损坏机制，并评估在高密度电流下的电气可靠性。在60 kA/cm 2电流负载下观察到由于EM的原子输运，并且在120 kA/cm 2电流负载下观察到相对大的聚集体和晶粒生长。开路时间在120 kA/cm 2下比在60 kA/cm 2下长。在两个电流密度值下观察到大聚集体的形成和电位降的不稳定变化。认为聚集体的形成和晶粒的长大影响了原子的输运。
Flexible printed circuits (FPCs) are widely used in electronic equipment such as mobile devices and wearable sensors. The conductive electric lines in these circuits are printed using nanoparticle metal ink and ink-jet direct write methods. Physical characteristics such as flexibility and mechanical durability of metal nanoparticle ink lines have been evaluated by bending or tensile tests. In contrast, the electrical characteristics of these lines have not been sufficiently evaluated, and the failure mechanism under high-density current has not been clarified. When electric devices are scaled down, current density and Joule heating increase in conductive lines and electromigration (EM) damage becomes a severe problem. Therefore, reducing the EM damage is extremely important to enhance the device reliability. In this study, a failure analysis of Ag nanoparticle ink lines were assessed using current loading tests and microscopic observations to discuss the damage mechanism and evaluate electrical reliability under high-density current. Atomic transport due to EM was observed at 60 kA/cm2 current loading, and relatively large aggregates and grain growth were observed at 120 kA/cm2 current loading. The time to open circuit was longer at 120 kA/cm2 than at 60 kA/cm2. The formation of large aggregates and unstable changes in the potential drop were observed at the two values of current density. It is considered that aggregate formation and grain growth affected the atomic transport by EM.