Temperature-dependent characteristics for the p-type CuO gate HEMT and high-k HfO2 MIS-HEMT on the Si substrates

This work presents the temperature-dependent characteristics of the thin-barrier Al0.45Ga0.55N/GaN high electron mobility transistor (HEMT), p-type CuO gate HEMT, and high-k HfO2 metal–insulator–semiconductor HEMT (MIS-HEMT). As the temperature rises from 20 to 300 °C, the maximum trans-conductance of the HfO2 MIS-HEMT and CuO gate HEMT reduces by 56.9% and 43.2%, respectively. The sub-threshold swing of the CuO gate HEMT is smaller than that of the HfO2 device when the temperature reaches 300 °C. According to the C–V test results from 20 to 300 °C, the relative dielectric constant of CuO increases from 18.1 to 47.4, whereas HfO2 has a relatively stable dielectric constant. The calculation models are presented to investigate the effect of the dielectric constant on the drain current and the trans-conductance. The calculated results show that the maximum transconductance of the HfO2 MIS-HEMT and CuO gate HEMT decreases by 52.3% and 38.9%, respectively, which is in good agreement with the experimental results.