Flexible electronics require more compact interconnects for next-generation devices. Polymer devices can be bonded to integrated circuit chips, but combining flexible and rigid substrates poses unique technical challenges. Existing technologies either cannot achieve the density required for modern chips or employ specialized equipment and complex processes to do so. Here, we adapt several approaches to achieve fine-pitch bonding between rigid and flexible substrates including epoxy, ultrasonic wire, and anisotropic conductive film bonding and also introduce a novel technique called polymer ultrasonic on bump (PUB) bonding. Using Parylene C devices and various rigid substrates as our model testbed systems, we investigate these four methods across a range of bond pad size and pitch by measuring yield and resistance and by subjecting devices to thermomechanical reliability tests. We demonstrate that all methods are capable of bonding fine pitch interconnects (100 m) at low temperature (<100 C). Additionally, we focus on PUB bonding and join a packaged chip and a bare die to Parylene devices.

柔性电子产品需要更紧凑的互连用于下一代设备。聚合物器件可以键合到集成电路芯片上，但结合柔性和刚性基板提出了独特的技术挑战。现有技术要么无法达到现代芯片所需的密度，要么采用专门的设备和复杂的工艺来做到这一点。在这里，我们采用了几种方法来实现刚性和柔性基板之间的小间距键合，包括环氧树脂、超声波线和各向异性导电膜键合，并介绍了一种称为凸点上聚合物超声波 (PUB) 键合的新技术。使用 Parylene C 器件和各种刚性基板作为我们的模型试验台系统，我们通过测量良率和电阻以及对器件进行热机械可靠性测试，在一系列焊盘尺寸和间距范围内研究这四种方法。我们证明了所有方法都能够粘合细间距互连（100m) 在低温 (<100 C) 下。此外，我们专注于 PUB 键合，并将封装芯片和裸片连接到 Parylene 设备。