Buried-Gate Flexible CNT FET with HZO Dielectric on Mica Substrate

Carbon nanotube field-effect transistors (CNT FETs) are considered strong candidates for next-generation flexible electronics due to their excellent carrier mobility and mechanical flexibility. However, the fabrication of CNT FETs on conventional flexible substrates such as PI or PET is often limited by surface roughness, chemical incompatibility, and poor mechanical robustness, resulting in degraded device performance. In this study, we report the fabrication of buried-gate CNT FETs incorporating Hf_0.5Zr_0.5O₂ as the gate dielectric on mica substrates, which offer high surface flatness, low defect density, and superior mechanical durability. The fabricated devices exhibit outstanding electrical characteristics, including a field-effect mobility of 38.4 cm²/V·s, a subthreshold swing of 93 mV/dec, and a transconductance of 14.2 μS. These results demonstrate the excellent mechanical stability and reliable electrical performance of the proposed devices under bending stress, highlighting their suitability for mechanically demanding flexible electronics applications.