First Demonstration of High-Performance and Extremely Stable W-Doped In₂O₃ Gate-All-Around (GAA) Nanosheet FET

We demonstrate a gate-all-around (GAA) nanosheet FET featuring an atomic layer-deposited (ALD) tungsten (W)-doped indium oxide (In2O3), or indium tungsten oxide (IWO), channel. A novel channel release process is developed, utilizing wet etching with an etching selectivity exceeding 103 between the channel and a metal sacrificial layer (SL), enabling lithography-independent definition of the device channel length (LCh). The fabricated nanosheet FETs, with scaled dimensions ofLCh =50nm and WNanosheet =30nm, exhibit a high on-state current (ION) of815~μA/μm at VDS =1V and VG-VT =3.5V, along with an ultralow off-state current (IOFF) of 3 fA. These IWO-GAA nanosheet FETs are demonstrated to achieve exceptional threshold voltage stability under both positive (PBTI) and negative (NBTI) bias stress conditions, with the hero device achieving a record-low threshold voltage shift (Δ VT) of 88 mV for a stress voltage of VG-VT =2.6V, corresponding to a stress field (EStress) of 5.4 MV/cm.