From Printed Devices to Vertically Stacked, 3D Flexible Hybrid Systems

The pursuit of miniaturized Si electronics has revolutionized computing and communication. During recent years, the value addition in electronics has also been achieved through printing, flexible and stretchable electronics form factors, and integration over areas larger than wafer size. Unlike Si semiconductor manufacturing which takes months from tape-out to wafer production, printed electronics offers greater flexibility and fast-prototyping capabilities with lesser resources and waste generation. While significant advances have been made with various types of printed sensors and other passive devices, printed circuits still lag behind Si-based electronics in terms of performance, integration density, and functionality. In this regard, recent advances using high-resolution printing coupled with the use of high mobility materials and device engineering, for both in-plane and out-of-plane integration, raise hopes. This paper focuses on the progress in printed electronics, highlighting emerging printing technologies and related aspects such as resource efficiency, environmental impact, integration scale, and the novel functionalities enabled by vertical integration of printed electronics. By highlighting these advances, this paper intends to reveal the future promise of printed electronics as a sustainable and resource-efficient route for realizing high-performance integrated circuits and systems.