Effects of hydrostatic pressure and temperature on the AlGaN/GaN high electron mobility transistors

In this paper, the drain-source current, transconductance, and cutoff frequency in AlGaN/GaN high electron mobility transistors have been investigated. In order to obtain the exact parameters of AlGaN/GaN high electron mobility transistors such as the electron density, wave function, band gap, polarization charge, effective mass, and dielectric constant, the hydrostatic pressure and temperature effects are taken into account. It has been found that the drainsource current decreases as the temperature increases and increases as the hydrostatic pressure increases. The increase in temperature is equivalent to a negative virtual gate while an increase in the hydrostatic pressure is equivalent to the positive virtual gate voltage. Moreover, the temperature, hydrostatic pressure, and effective mass dependence in high electron mobility transistor structures are investigated. It is observed that the increase of hydrostatic pressure decreases the effective mass as the wave function penetrates through the quantum barrier AlGaN. In general, the process of increasing and decreasing the cutoff frequency and transconductance is similar to the variations in the drain-source current. The calculated results are in good agreement with the existing experimental data.