Negative Capacitance MgZnO-Channel Thin-Film Transistor With Ferroelectric NiMgZnO in the Gate Stack

We demonstrate the negative capacitance thin-film transistor (NC-TFT) on glass substrate using the multifunctional MgZnO (MZO). The Mg _0.03 Zn _0.97 O semiconductor layer acts as the TFT channel for stable operation while the Ni-doped MZO, i.e. Ni _0.02 Mg _0.15 Zn _0.83 O (NMZO) serves as the ferroelectric layer in the NMZO/SiO ₂ stacking gate dielectric structure. The subthreshold swing (SS) value is significantly reduced over the reference TFT without ferroelectric layer. The minimum SS value of the NC-TFT reaches 52 mV/dec while the on/off ratio of drain current ID reaches 109.