Microheater integration in gate dielectric functionalized a-IGZO thin film transistors for methanol sensing

Volatile organic compound sensors continue to face challenges in achieving key requirements for their practical use. In this context, metal-organic framework functionalized field-effect transistors hold great potential as game-changers in gas sensing, however, they are prone to baseline drift as many other gas sensing technologies. To address this issue, we integrated a microheater to facilitate degassing of residual gases. The thermal distribution of the microheater was evaluated by using temperature-sensing test structures. Additionally, the importance of the metal-organic framework as an enabler for methanol sensing was demonstrated. The influence of temperature pulses on the intrinsic characteristics of the a-IGZO channel was further addressed, showing a reversible de-trapping of electrons. By applying heating pulses of 100°C from the integrated microheater, the baseline drift caused by residual methanol was successfully corrected.