Steep-slope field-effect transistors with AlGaN/GaN HEMT and oxide-based threshold switching device

We report the demonstration of a steep-slope field-effect transistor with AlGaN/GaN MIS-HEMTs employing SiO₂-based threshold switching devices in series with the source. The SiO₂-based threshold switching devices exhibited steep slope when changing resistance states. The integrated steep-slope transistor showed a low subthreshold swing of sub-5 mV/dec with a transition range of over 10⁵ in the transfer characteristics in both sweep directions at room temperature, as well as the low leakage current (10^-5 μA μm^-1) and a high I _ON/I _OFF ratio (>10⁷). Moreover, with the SiO₂-based threshold switching devices we also observed a positive shift of threshold voltages of the integrated device. Results from more than 50 transfer characteristics measurements also indicate the good repeatability and practicability of such a steep-switching device, where the average steep slopes are below 10 mV/decade. This steep-slope transistor with oxide-based threshold switching devices can be further extended to various transistor platforms like Si and III-V and are of potential interest for the development of power switching and high frequency devices.