Lattice degradation by moving voids during reversible electromigration

Abstract

Electromigration driven void motion is studied in Ag wires with an initially well-defined single crystal lattice by in situ scanning electron microscopy. Voids are moving in opposite direction to the electron flow. When the electron current is reversed, voids exactly retrace their previous motion path with an increased drift velocity: The microstructure of the Ag wire “remembers” the motion path of the initial voids. To investigate the nature of this memory effect, we analyzed the crystal lattice with electron backscatter diffraction after passing of a void. The results show a permanent lattice degradation caused by the moving void. The implication of this finding for the reversibility of EM will be discussed.

Linearly Polarized Electroluminescence from MoS2 Monolayers Deposited on Metal Nanoparticles: Toward Tunable Room‐Temperature Single‐Photon Sources

“…Since electromigration leads to mass transport in the metal film, [47][48][49] it is instructive to analyze the electromigrated sample with an atomic force microscope (AFM) to determine whether the structure of the TMDC monolayer is preserved. Figure 1e shows a non-contact AFM topography image of the breakjunction region.…”

Electromigration in Gold Films on Flexible Polyimide Substrates as a Self-healing Mechanism

“…The literature also reports about alternating current experiments and reversible EM phenomena. [ 13 , 15 , 16 ]…”

Degradation Mechanism of Silver Nanowire Transparent Conductive Films: a Review

“…4 (a) Finite-element simulation of the current flow through a two AgNW junction [22] ; (b, c) SEM images of a 12 Ω/ AgNW electrode under a constant current density of 17 mA/cm 2 for 17 d [21] ; (d-f) SEM image of AgNW network under Joule heating [22] [23] 。光照会在银纳米线 上产生表面等离激元共振效应, 使得银纳米线网络 局域温度升高, 形成"热点"。 与焦耳热效应类似, 诱 导银离子的迁移, 降低银纳米线之间的结电阻, 同 时, 过度的光照也加速了银纳米线向球形纳米颗粒 的转化 [24] 。此外, 除了银颗粒的产生和迁移外, 光 照还会加速银纳米线表面的硫化 [25] 。这些都会影响 银纳米线电极的实际应用。 对银纳米线在光照条件下形貌变化的研究表明 在光照诱导下生成的银纳米颗粒主要沿银纳米线呈 直线分布(图 5(a)), 生成原因是光照加剧了银纳米 线的硫化 [23] [23] Fig. 5 The morphology of the small nanodots and large particles emerged on/around silver nanowires after light irradiation [23] (a) The small nanodots on/around single AgNW; (b) The small nanodots on/around AgNWs with different diameters; (c) The small nanodots at the end of AgNW and also the large particle at the wire-wire junction with inset showing the high magnification image; (d) The large particle adjoined AgNWs 发生迁移的现象。而银的静电放电损伤阈值较低, 因此很容易发生电迁移现象 [20] [26] Fig. 6 SEM images of a bi-crystalline AgNW under a current of 54 mA [26] (a) Prior electrical stressing; (b-e) The direction of vacancy movement when the current flows to the left; (f-i) The direction of vacancy movement when the current moves to the right; (k-n) Surface morphology SEM images of the AgNW network in different stages of degradation [27] : [28] 。大面积单层石墨烯对气体的阻 隔效果更好, 也被用于作为封装层来提高银纳米线 的耐腐蚀性, 同时不会明显弱化薄膜的光电性能, 但是缺点是制备方法较复杂 [29] 。 最近, Liu 等 [28] [13] 、还原氧化石 墨烯 [15] 、TiO 2 [30] 、ZnO [31] [12] 也发现, 使用 AP-SALD 方法沉积 ZnO 层后, 银纳 图 7 针对银纳米线的失效形式所提出的具体解决措施 Fig.…”

“…5 The morphology of the small nanodots and large particles emerged on/around silver nanowires after light irradiation [23] (a) The small nanodots on/around single AgNW; (b) The small nanodots on/around AgNWs with different diameters; (c) The small nanodots at the end of AgNW and also the large particle at the wire-wire junction with inset showing the high magnification image; (d) The large particle adjoined AgNWs 发生迁移的现象。而银的静电放电损伤阈值较低, 因此很容易发生电迁移现象 [20] [26] Fig. 6 SEM images of a bi-crystalline AgNW under a current of 54 mA [26] (a) Prior electrical stressing; (b-e) The direction of vacancy movement when the current flows to the left; (f-i) The direction of vacancy movement when the current moves to the right; (k-n) Surface morphology SEM images of the AgNW network in different stages of degradation [27] : [28] 。大面积单层石墨烯对气体的阻 隔效果更好, 也被用于作为封装层来提高银纳米线 的耐腐蚀性, 同时不会明显弱化薄膜的光电性能, 但是缺点是制备方法较复杂 [29] 。 最近, Liu 等 [28] [13] 、还原氧化石 墨烯 [15] 、TiO 2 [30] 、ZnO [31] [12] 也发现, 使用 AP-SALD 方法沉积 ZnO 层后, 银纳 图 7 针对银纳米线的失效形式所提出的具体解决措施 Fig. 7 Remedy strategy of silver nanowire degradation (a) A self-assembled organic 2-mercaptobenzimidazole (MBI) used as an inhibitor of AgNWs [28] ;…”