Controlled Mechanical Cracking of Metal Films Deposited on Polydimethylsiloxane (PDMS)
Controlled Mechanical Cracking of Metal Films Deposited on Polydimethylsiloxane (PDMS)
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DOI：
10.3390/nano6090168
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发表时间：
2016-09-01
期刊：
影响因子：
5.3
通讯作者：
Goerrn, Patrick
中科院分区：
文献类型：
--
作者：
Polywka, Andreas;Stegers, Luca;Goerrn, Patrick
可拉伸的大面积电子设备符合任意形状的3D表面，并能够舒适地接触人体皮肤和其他生物组织。有一些方法可以使大面积薄膜被拉伸百分之十而不开裂。这里提出的方法不防止裂缝，而是旨在精确控制裂缝的位置和他们的方向。为此，聚二甲基硅氧烷（PDMS）通过暴露面罩暴露在紫外线辐射（172 nm）下硬化。只有定义良好的模式才不会被处理。有了这些软岛，硬化表面上的裂缝可以在开始位置、方向和结束位置上进行控制。该方法首先在硬化的PDMS表面本身进行了研究。然后将其应用于从液相沉积的导电银膜。结果表明，在应变低于35%时，可以避免银膜的统计（非控制）开裂。这使得金属互连可以集成到可拉伸的网络中。控制裂缝与起皱的结合使互连在任意和改变方向上可拉伸。沉积和图案化不涉及真空处理、光刻或溶剂。
Stretchable large area electronics conform to arbitrarily-shaped 3D surfaces and enables comfortable contact to the human skin and other biological tissue. There are approaches allowing for large area thin films to be stretched by tens of percent without cracking. The approach presented here does not prevent cracking, rather it aims to precisely control the crack positions and their orientation. For this purpose, the polydimethylsiloxane (PDMS) is hardened by exposure to ultraviolet radiation (172 nm) through an exposure mask. Only well-defined patterns are kept untreated. With these soft islands cracks at the hardened surface can be controlled in terms of starting position, direction and end position. This approach is first investigated at the hardened PDMS surface itself. It is then applied to conductive silver films deposited from the liquid phase. It is found that statistical (uncontrolled) cracking of the silver films can be avoided at strain below 35%. This enables metal interconnects to be integrated into stretchable networks. The combination of controlled cracks with wrinkling enables interconnects that are stretchable in arbitrary and changing directions. The deposition and patterning does not involve vacuum processing, photolithography, or solvents.