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).