Ki-Hwan Jang

CAD/CAM for scalable nanomanufacturing: A network-based system for hybrid 3D printing

Micro- and nano-structuring have been highlighted over several decades in both science and engineering fields. In addition to continuous efforts in fabrication techniques, investigations in scalable nanomanufacturing have been pursued to achieve reduced feature size, fewer constraints in terms of materials and dimensional complexity, as well as improved process throughput. In this study, based on recent micro-/nanoscale fabrication processes, characteristics and key requirements for computer-aided design and manufacturing (CAD/CAM) systems for scalable nanomanufacturing were investigated. Requirements include a process knowledge database, standardized processing, active communication, adaptive interpolation, a consistent coordinate system, and management of peripheral devices. For scalable nanomanufacturing, it is important to consider the flexibility and expandability of each process, because hybrid and bridging processes represent effective ways to expand process capabilities. As an example, we describe a novel CAD/CAM system for hybrid three-dimensional (3D) printing at the nanoscale. This novel hybrid process was developed by bridging aerodynamically focused nanoparticle printing, focused ion beam milling, micromachining, and spin-coating processes. The system developed can print a full 3D structure using various inorganic materials, with a minimum process scale of 50 nm. The most obvious difference versus CAD/CAM at ‘conventional’ scales is that our system was developed based on a network to promote communication between users and process operators. With the network-based system, it is also possible to narrow the gap among different processes/resources. We anticipate that this approach can contribute to the development of CAD/CAM for scalable nanomanufacturing and a wide range of hybrid processes.

In-Situ Characterization of Nano-Structures Fabricated by Focused Ion Beam (FIB) and Nano Particle Deposition System (NPDS)

Nano particle deposition system (NPDS) had been developed for the creation of micro/nano structures with multimaterials in order to develop the micro/nano devices on the basis of specific localized surface on the multilayer. However, micro structures fabricated by NPDS show different mechanical properties when it compared to bulk material because of its porous and uneven deposition structure. To achieve reasonable mechanical properties of the structure fabricated by nanoscale 3D printing system, it requires in-situ mechanical property test method. Herein, a new approach for in-situ nanomechanical characterization system using microforce sensor and nanomanipulator installed in focused ion beam system. In this research, experimental setup for mechanical characterization was developed and mechanical property test was done in Focused Ion Beam (FIB) system. The specimen was fabricated by FIB milling process, then manipulation and compression processes are operated by this characterization system with real time imaging. The test was done for silver microstructures fabricated by NPDS and results show weaker hardness and smaller young’s modulus than bulk material.Copyright

Alignment Algorithm for Nano-scale Three-dimensional Printing System

Hybrid manufacturing technology has been advanced to overcome limitations due to traditional fabrication methods. To fabricate a micro/nano-scale structure, various manufacturing technologies such as lithography and etching were attempted. Since these manufacturing processes are limited by their materials, temperature and features, it is necessary to develop a new three-dimensional (3D) printing method. A novel nano-scale 3D printing system was developed consisting of the Nano-Particle Deposition System (NPDS) and the Focused Ion Beam (FIB) to overcome these limitations. By repeating deposition and machining processes, it was possible to fabricate micro/nano-scale 3D structures with various metals and ceramics. Since each process works in different chambers, a transfer process is required. In this research, nanoscale 3D printing system was briefly explained and an alignment algorithm for nano-scale 3D printing system was developed. Implementing the algorithm leads to an accepted error margin of 0.5% by compensating error in rotational, horizontal, and vertical axes.