High-Voltage Indium-Tin-Oxide Thin-Film Transistors Possessing Drift Region Capped With Indium-Tin-Oxide Layer

Indium-tin-oxide (ITO) possesses high carrier mobility and a wide bandgap, which is a promising candidate for fabricating high-voltage (HV) thin-film transistors (TFTs) with a low on-resistance. No reports exist on HV ITO TFTs due to the limitation of the traditional TFT structure. This paper presents HV ITO TFTs featuring a drift region situated between the gate and drain. A 6-nm thick ITO channel is used, with the drift region spanning from 4 μm to 20 μm, encapsulated by an ITO layer ranging in thickness from 0 nm to 20 nm. Finally, an HV ITO TFT with a breakdown voltage (V _BD ) of 448 V and a low specific on-resistance (R _{on, sp} ) of 147 mΩ·cm ² is realized. The trade-off relationship between V _BD and R _on,sp of proposed HV ITO TFTs approaches the theoretical limit of the single-RESURF lateral double-diffused MOSFET (LDMOS).