Research in stretchable electronics is helping to revolutionize the current electronic industry, particularly in wearable and bio-integrated devices. Cost-effectiveness and easy manufacturing are key factors that contribute to shaping the fate of such technologies. In this work, we present a fabrication method for a novel ultra-stretchable, serpentine-arm spiral (SAS) that was built using a low-cost, standard bulk silicon (100) wafer. However, structural defects that often appear during patterning processes, can lead to stress concentration and structural failure at these sites upon stretching. Parylene coating of the structures is proposed to minimize this stress concentration and improve structure’s robustness. Finite element analysis (FEA) was performed to demonstrate the concentration of stress at these defective sites with 2 sizes (0.$1\mathrm{\mu }\mathrm{m}$ and $1\mathrm{\mu }\mathrm{m}$) and at different locations along the arms. Results show that SAS structures reach up to $\sim$80% stress reduction at the defective location compared to straight-arm spirals, while the parylene-coating helps to reduce it up to $\sim$60% further. On the other hand, fabricated uncoated, SAS structures reached up to $\sim$600% prescribed strain before fracture, while parylene-coating improves this maximum admissible strain in $\sim$50%. Additionally, a cyclic tensile test was then performed on the fabricated structures, uncoated and parylene-coated, for over 3000 cycles without fracture. The results observed on coated structures greatly improve the mechanical reliance of such brittle structures, which could be extended to other stretchable configurations.

可伸缩电子学的研究正在帮助革新当前的电子工业，尤其是可穿戴和生物集成设备。成本效益和易于制造是决定这种技术命运的关键因素。在这项工作中，我们提出了一种新颖的超可拉伸蛇形臂螺旋（SAS）的制造方法，该制造方法是使用低成本的标准块状硅（100）晶圆制造的。但是，在构图过程中经常出现的结构缺陷会在拉伸时导致应力集中和这些位置的结构破坏。建议使用结构的聚对二甲苯涂层来最小化这种应力集中并提高结构的坚固性。进行了有限元分析（FEA），以证明这些缺陷部位的应力集中为2个尺寸（0。$\mathrm{1个}\mathrm{\mu }\mathrm{米}$ 和 $\mathrm{1个}\mathrm{\mu }\mathrm{米}$），以及沿着手臂的不同位置。结果表明，SAS结构达到了$〜$与直臂螺旋相比，缺陷位置的应力降低了80％，而聚对二甲苯涂层有助于将应力降低到最大 $〜$进一步提高60％。另一方面，未镀膜的SAS结构达到了$〜$断裂前规定的应变为600％，而聚对二甲苯涂层可改善该最大允许应变 $〜$50％。另外，然后对未涂覆和聚对二甲苯涂覆的结构进行了循环拉伸试验，进行了3​​000多个循环而没有断裂。在涂层结构上观察到的结果大大改善了这种脆性结构的机械可靠性，可以将其扩展到其他可拉伸构造。