High performance enhancement-mode thin-film transistor with graphene quantum dot-decorated In2O3 channel layers

Abstract

Due to the quantum confinement and edge effects, there has been ongoing enthusiasm to provide deep insight into graphene quantum dots (GQDs), serving as attractive semiconductor materials. To demonstrate the potential applications of GQDs in electronic devices, this work presents solution-processed high performance GQD-decorated In₂O₃ thin-film transistors (TFTs) based on ZrO₂ as gate dielectrics. GQDs-In₂O₃/ZrO₂ TFTs with optimized doping content have demonstrated high electrical performance and low operating voltage, including a larger field-effect mobility (μ_FE) of 34.02 cm² V⁻¹ s⁻¹, a higher I_on/I_off of 4.55 × 10⁷, a smaller subthreshold swing (SS) of 0.08 V dec⁻¹, a lower interfacial trap states (D_it) of 5.84 × 10¹¹ cm⁻² and threshold voltage shift of 0.07 V and 0.12 V under positive bias stress (PBS) and negative bias stress (NBS) for 3600 s, respectively. As a demonstration of complex logic applications, a resistor-loaded unipolar inverter based on GQDs-In₂O₃/ZrO₂ has been built, demonstrating full swing characteristic and high gain of 10.63. Low-frequency noise (LFN) characteristics of GQDs-In₂O₃/ZrO₂ TFTs have been presented and it was concluded that the noise source can be attributed to the fluctuations in mobility. As a result, it can be concluded that solution-derived GDQ-optimized oxide-based TFTs will manifest potential applications in electronic devices.