(A) study on thin film encapsulation and transistor-based biosensor for the high performance flexible device

Abstract

As interest in personal health care increases, various biosensor products for health care are emerging along with healthy food. Although these biosensors are being continuously studied for wearable platforms to improve convenience and form factor, it is essential to secure stability and high sensitivity to the external environment to improve the marketability of flexible biosensors. In this study, a mono-layer silicon nitride based thin film encapsulation with excellent moisture barrier properties and long-term stability was developed by increasing the amount of Si-N bonding through an optimized plasma-enhanced chemical vapor deposition with the addition of hydrogen gas. In addition, high sensitivity was obtained by introducing a dual gate structure causing capacitive coupling effect to the oxide thin-film transistor, and excellent performance was confirmed by applying it to a biosensor for detecting COVID-19. Furthermore, the application of the biosensor as a flexible device was investigated by introducing it into a flexible platform.