Current challenges and potential directions towards precision microscale additive manufacturing – Part I: Direct ink writing/jetting processes

This paper is the first in a series of articles which comprehensively discuss the state-of-the-art in microscale additive manufacturing processes and present solutions to challenges impeding their scalability. In this paper, a class of additive manufacturing techniques known as Direct Ink Write/Jet Processes are explored which have been used by researchers for fabrication of microscale parts with varying geometric freedom. The paper identified the key challenges to high throughput 3D microfabrication using these processes, by analyzing the material constraints, geometric constraints, feature-size resolution limits and throughput limits. While some of these challenges can be overcome by novel precision engineering approaches, there are several others which need an acute understanding of material systems, process parameters and critical components. This paper identifies these challenges and suggests potential approaches to eliminate them with the goal of fabricating true-3D parts at high throughputs.