By designing different interlayers (Al, Si/SiN and Cr interlayer) and oxygen plasma pretreatment of the substrate, strong adhesion was realized for the double-layer flexible copper clad laminate on polyimide (PI) substrate via high power impulse magnetron sputtering (HiPIMS) technology. The microstructures and properties of Cu films on PI substrate were characterized by an X-ray powder diffractometer (XRD), X-ray photoelectron spectroscope (XPS), atom force microscopy (AFM), scanning electron microscope (SEM), nano-scratch test, scotch tape test and four-probe detector. With the introduction of interlayer and oxygen plasma pretreatment, the critical load of Cu film (300 nm thick) peaked at 43.5 mN and the sheet resistance ranged from 124 to 227 mΩ/sq. The oxygen plasma pretreatment resulted in the drastic oxidation to generate functional groups on the PI substrate surface, which contributed to the improvement of adhesion strength by chemical interaction in terms of the film with Si/SiN or Cr interlayer. Besides, for the Cu film with Si/SiN interlayer, the resistance against copper diffusion by the SiN layer can also promote the enhancement of adhesion strength.

中文翻译：

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通过 HiPIMS 沉积实现双层柔性覆铜层压板的强粘合力的层间设计


通过设计不同的中间层（Al、Si/SiN和Cr中间层）以及对基材进行氧等离子体预处理，采用高功率脉冲磁控溅射（HiPIMS）技术在聚酰亚胺（PI）基材上实现了双层柔性覆铜板的强附着力。技术。采用X射线粉末衍射仪(XRD)、X射线光电子能谱仪(XPS)、原子力显微镜(AFM)、扫描电子显微镜(SEM)、纳米划痕测试等手段对PI基体上Cu薄膜的微观结构和性能进行表征、透明胶带测试和四探针检测器。随着层间和氧等离子体预处理的引入，铜膜（300 nm 厚）的临界载荷达到 43.5 mN 峰值，方块电阻范围为 124 至 227 mΩ/sq。氧等离子体预处理导致PI基材表面发生剧烈氧化并产生官能团，这有助于通过薄膜与Si/SiN或Cr中间层的化学相互作用提高粘附强度。此外，对于具有Si/SiN中间层的Cu薄膜，SiN层对铜扩散的抵抗力也可以促进粘附强度的增强。