Advancements in High-Mobility SnO₂-Based Thin-Film Transistors: Unleashing the Potential for Next-Generation Electronics

The 7 nm nanosheet tin oxynitride (SnON) with 7.6 % nitrogen thin film transistor (TFT) exhibits a record high field-effect mobility (TFE) of 299 cm²N-s. The 5 nm thick nanosheet SnON TFT showed μ_FE of 277 cm²N-s compared to control SnO₂ device μ_FE of 211 cm²N-s with the same 5 nm thickness. According to quantum-mechanical calculations, the reason for the high μ_FE of nanosheet SnON TFT is its lower effective mass of electrons in the conduction band, which is 0.29 mo, compared to 0.41 mo for SnO₂. By injecting non-oxide anions and controlling the valence band by substitutional alloying with nitrogen anions, SnON can further lower defect trap densities, boost on-current (I_ON), and improve the transistor's mobility. This allows for the removal or passivation of oxygen vacancy levels. The SnON TFT device can be extensively deployed in advanced high-definition displays and monolithic 3D ICs.