This Small Business Innovation Research Phase I project aims to undertake a feasibility study of printing ultra-pure semiconducting and metallic single-walled carbon nanotube (SWCNT) inks as channel materials and electrodes of thin-film-transistors, and to fabricate all-SWCNT circuits such as inverters (< 5 V) and ring oscillators (> 1 kHz) in two-dimensional (2-D) and three-dimensional (3-D) architectures. The current trend of increasing electronic function per area, offering optical transparency, flexibility and lower cost, is driving products to be produced using printed electronics. This project will leverage existing inkjet printing technologies to implement all-SWCNT thin-film transistors and integrated circuits. To increase areal functional density and overcome interconnect parasitics, this project will aim to develop all-SWCNT printed devices in a 3-D architecture interconnected with metallic SWCNTs that will enable complete circuit transparency of the printed electronics for optoelectronic and display applications. Areal functional density will be increased, and functionalities such as signal delay and power consumption will be improved as a result. Printed integrated circuits based on transistors constructed and interconnected using single-walled carbon nanotubes (SWCNTs) are highly desirable for low cost, vacuum-less, scalable, and flexible applications such as backplane displays, radio frequency identification tags, electronic paper and disposable electronics.
The broader impact/commercial potential of this project is all-SWCNT thin-film transistors (TFTs) and circuits of fully-transparent, flexible, dense materials. Creation of these devices will enable products in backplane displays and solar equipment, non-volatile memories, disposable electronics, and semiconductor manufacturing and will impact a plethora of low-cost consumer electronics products. Using metal electrodes compromises a circuit's transparency, flexibility, and mechanical strength. Our all-SWNCT devices will overcome these limitations, as no solid, opaque materials will be employed. This project has the potential to greatly augment the printed electronic industry that is expected to grow to $24 billion in 2015, with an astonishing current growth rate of over 30% per year.
Impact Statement: Aneeve Nanotechnologies is the first to develop a "fully" printed ink-jet CNT transistor and transparent technology via this NSF SBIR Phase 1 project. This project successfully developed a transparent 3D CNT printing platform that would enable low cost transparent display consumer products. This is a significant breakthgough since the transparent display market is expected to grow from US$0.9 billion in 2015 to US$87 billion in 2025. Exploding consumer demand and trends towards low power and wireless consumer devices such as "Google Goggles" and jazzy wireless phones is expected to drive this market in addition to transparent display windows for buildings/vehicles/aircrafts. Intellectual Merit: Printed integrated circuits based on transistors constructed and interconnected using single-walled carbon nanotubes (SWCNTs) are highly desirable for low cost, vacuum-less, scalable and flexible applications such as backplane display, radio frequency identification tags, electronic papers and disposable electronics. The current trend in increasing electronic function per area, offering optical transparency, flexibility and low cost is driving products produced using printed electronics. This SBIR Phase I project demonstrated the feasibility of printing ultra-pure semiconducting and metallic SWCNT inks as channel materials and electrodes of thin-film-transistors and to fabricate all-SWCNT devices and circuits Broader Impacts: Among these emerging thin-film transistors (TFTs), semiconducting SWCNTs are promising as thin-film transistors due to their excellent air-stable, mechanic and electric properties. Companies such as Applied Materials, Samsung and LG are active in developing printed electronic technology for TFTs that employ metal electrodes. Using metal electrodes compromises a circuits transparency, flexibility, and mechanic strength. As demonstrated in this SBIR Phase 1, our approach using all-SWNCT overcomes these limitations as no solid opaque metal materials are employed. As such, our CNT based circuits remain fully transparent, with high function/area that opens opportunities to applications and products in backplane displays and solar equipment, non-volatile memory, disposable electronics & semiconductor manufacturing and will impact a plethora of low cost consumer electronics products such as next generation transparent displays.
