Low-Power Microwave Annealing Effect for Random Carbon Nanotube Network-Based Thin-Film Transistors and Inverter Circuits

We investigated a low-power microwave annealing (MWA) process for improving the electrical characteristics of random carbon nanotube (CNT) network-based thin-film transistors (TFTs) and diode-load inverter circuits without thermal damage. The low-power MWA process was applied to post-deposition annealing for removing defects and charge traps in CNT TFTs and compared with conventional thermal annealing (CTA). The results indicated that the low-power MWA-processed devices had better electrical characteristics and process yields than the CTA-processed devices, at the same process temperature. As the annealing temperature of the CTA-processed device increased, thermal damage occurred in the CNT channel layer, leading to a reduction in the device yield and deterioration of the electrical characteristics. A diode-load inverter circuit was fabricated using CNT TFTs, and the inverter output characteristics were improved by the defect reduction owing to the low-power MWA processing.