Swing-Tunable Oxide Thin-Film Transistors via Electrohydrodynamic Jet-Printed Parasitic Conduction Path

Precise control over the subthreshold swing (SS) of oxide thin-film transistors (TFTs) is critical for advanced display and low-power electronic systems. Here, we present a swing-tunable TFT (ST-TFT) using electrohydrodynamic (EHD) jet printed parasitic conduction path (PPCP) on an indium gallium zinc oxide (IGZO) channel. By tuning PPCP width and processing conditions, SS is reproducibly modulated from 0.36 to 1.58 V/dec without degrading mobility or operational stability. Structural and chemical analyses reveal that indium diffusion induces partial crystallization and oxygen vacancy formation in the IGZO back-channel, enabling stable hump conduction. Optimized ST-TFTs widen the OLED grayscale control range from 0.6 to 2.6 V and boost peak luminance from 1944 to 2758 cd/m². SmartSpice simulations confirm reduced panel-level luminance nonuniformity under IR drop from 43.75 to 15.63%, without compensation circuitry. The PPCP-enabled stable intermediate conduction states provide a platform for multilevel logic and neuromorphic oxide electronics, highlighting ST-TFTs as a scalable solution for emerging electronics.