On the Electrical and Thermal Study of a MgZnO/ZnO HEMT for High Field Applications

In this work, a simple current equation of a HEMT based on MgZnO and ZnO heterojunction is proposed in the framework of electron velocity saturation. The mathematical formulation of drain current is presented as a function of mole fraction and device temperature. It is observed that the effect of the mole fraction of MgZnO has a significant role to modulate the drain current of the device. For example, the drain current is shifted by almost 9% for a change in mole fraction from 0.2 (236.5mA) to 0.5 (257.2mA) when no gate voltage is applied. In addition to this, the impact of environmental thermal variation is included in our study and a noticeable shift of drain current and other device parameter has been observed for a temperature range 300K to 500K. This work has also been extended to study the switching characteristics of the device in terms of mole fraction of MgZnO and ambient temperature. It is observed that the threshold voltage is shifted by 0.36 V for a change in mole fraction by 0.2.