MgZnO-Based Negative Capacitance Transparent Thin-Film Transistor Built on Glass

We demonstrate the first wide bandgap oxide based negative capacitance transparent thin-film transistor (NC-TTFT) built on glass. The Mg0.03Zn0.97O (MZO) semiconductor served as the channel layer and ferroelectric Ni0.02Mg0.15Zn0.83O (NMZO) serves in the gate stack. The Al-doped ZnO (AZO) is employed as the transparent conductive oxide (TCO) for source and drain electrodes. The NC-TTFT on glass shows an average optical transmittance of 91 % in the visible spectrum. The subthreshold swing (SS) value is significantly reduced over the reference transparent thin-film transistor (TTFT) without a ferroelectric layer. The minimum SS value of the NC-TTFT reaches 17 mV/dec. With normally-off operation and high on/off current ratio of 107, this NC-TTFT on glass technology shows promising potential for wearable systems such as augmented reality (AR) smart glasses.