A Multiscale Assembly and Packaging System for Manufacturing of Complex Micro-Nano Devices

Reliable manufacturability has always been a major issue in commercialization of complex and heterogeneous microsystems. Though successful for simpler and monolithic microdevices such as accelerometers and pressure sensors of early days, conventional surface micromachining techniques, and in-plane mechanisms do not prove suffice to address the manufacturing of today's wide range of microsystem designs. This has led to the evolution of microassembly as an alternative and enabling technology which can, in principle, build complex systems by assembling heterogeneous microparts of comparatively simpler design; thus reducing the overall footprint of the device and providing high structural rigidity in a cost efficient manner. However, unlike in macroscale assembly systems, microassembly does not enjoy the flexibility of having ready-to-use manipulation systems or standard off-the-shelf components. System specific designs of microparts and mechanisms make the fabrication process expensive and assembly scheme diverse. This warrants for a modular microassembly cell which can execute the assembly process of multiple microsystems by reconfiguring the kinematics setup, end-effectors, feedback system, etc.; thus minimizing the cost of production. In this paper, we present a multiscale assembly and packaging system (MAPS) comprising of 20 degrees of freedom (DoFs) that can be arranged in several reconfigurable micromanipulation modules depending on the specific task. The system has been equipped with multiple custom-designed microgrippers and end-effectors for different applications. Stereo microscopic vision is achieved through four high-resolution cameras. We will demonstrate the construction of two different microsystems using this microassembly cell; the first one is a miniature optical spectrum analyzer called microspectrometer and the second one is a MEMS mobile robot/conveyor called Arripede. Note to Practitioners-This paper describes the development of an modular and reconfigurable assembly system for construction of complex, heterogeneous 3D micro-nano systems. The emphasis is on manufacturability aspects such as yield, throughput and cost in process automation. The system components include precision robots, micro-stages, end-effectors, and fixtures that accomplish assembly tasks in a shared workspace along with other process tools. High assembly yield is guaranteed by the application of a so-called Resolution-Repeatability- Accuracy (RRA) precision design rule. We present experimental results demonstrating how different microsystems are assembled within specified tolerance budgets, with high yield, using a systematic planning and a hybrid control structure and minimalist hardware approach.