Overcoming Non-linearity in Transistors with Printed Biodegradable Thin Film Transistors

Incessant demand for electronics produces huge amount of electronic waste (E-waste). E-waste contains substances that cannot be decomposed and are hazardous to the environment such as lead. Although electronics industries have focused on computing power and miniaturization in last three decades, they have not focussed on safe materials and processes that generate less hazardous material waste. As such, there is a need for the development of new bio-degradable electronics that are environmentally safe, disposable, and can be produced in large volume at low-cost with less chemical waste. Printed electronics (PE), because of its additive nature is evolving as a practical and environment friendly alternative to conventional microfabrication due to its cost-efficiency, ability to produce large area electronics, less to no hazardous material waste and flexible form factor. Therefore, use of biodegradable material along with PE can reduce E-waste. Since transistors are one of the basic building blocks of modern electronics, it is important to develop biodegradable transistors. Although researchers have reported biodegradable transistors, that are typically fabricated with complex traditional subtractive microfabrication techniques involving hazardous material waste. These transistors contain materials that need to be degraded under certain chemical conditions, and produce hazardous by-products. In these contexts, we propose to design and develop biodegradable environmentally safe thin film transistor (TFT) with PE technology. For the TFT structure we choose the multimodal transistor (MMT) as MMT's structure is simple enough to be fabricated with PE and it provides a unique linear behavior. Non-linearity in transistors causes various issues for devices such as distortion in amplifiers. In this project, we will develop and characterize high performance long lasting (few years life time) biodegradable materials for different layers of MMT and come up with processes to deposit them with printing processes. The printed MMT structure will be designed and fabricated using those materials and processes to achieve good performance such as linearity, high gain, high on-off ratio and low power requirement. After successful characterization of MMT, a low distortion amplifier will be designed and developed with the MMT. Successful completion of the project will help to overcome two existing major issues in electronics area: 1) E-waste and 2) non-linearity of transistors.