STTR Phase I: Development of High-Speed Infrared-Transparent Flexible Transistors Using Electronic-Grade Carbon Nanotube Solutions

This Small Business Technology Transfer (STTR) Phase I research project aims to develop an innovative high speed IR-transparent flexible thin-film transistor (TFT) technology for application to conformal IR invisible electronics by using unique electronic-grade carbon nanotube (CNT) solutions that contain individually suspended ultrapure CNTs without any surfactant. With numerous simple solution-casting methods, ultrapure CNT films of various densities can be formed. Such films possess ultrahigh carrier mobility, great mechanical resilience, and superior IR transmittance. Meanwhile, the unique room-temperature solution-processable CNTs would enable mass production of large-area high-speed conformal integrated circuits on virtually any desired flexible substrate at low cost and high throughput without the need for special lithography equipment. In Phase I, a prototype flexible CNT-TFT will be fabricated for conducting technical feasibility investigation, and potential commercial feasibility will be assessed. The work in Phase II would concentrate on achieving large-area high-speed IR-invisible integrated circuits on flexible substrates at low cost and high throughput. Through this project electronic structures and IR properties of CNT films will be further revealed. Bandgap engineering techniques will be developed to enable the tuning of electrical and optical properties of CNT films. Purification techniques and post-fabrication processes will be optimized to enhance the field-effect mobility and the on-off ratio of CNT-TFTs. Various solution-casting methods will be explored to achieve high-rate cost-effective manufacturing of large-area integrated circuits on flexible substrates. The outcomes of this project will provide a solid base for developing a family of electronic-grade CNT solution products suitable for a great variety of applications. This project is potentially importance for a great variety of applications, such as flexible electronics, IR-invisible antennas, and embedded IR sensing, imaging, and communications. This project will train both industry workers and college students in cutting-edge cross-disciplinary areas of Nanomaterial Science and Nanoelectronics. Internships will be offered to students as part of the industry training, which will help to provide and maintain qualified hi-tech work forces in the United States.