The Impact Of Pressure On Transport Properties Of AlGaN/GaN High Electron Mobility Transister

As been the third-generation semiconductor material, GaN have been researched and used by many different fields, and AlGaN/GaN-HEMT has been widely used by science and medical. It also attracted sensor field because of the stability and effective. Basing on the application of the pressure sensor on GaN, the article researched the impact of pressure on transport properties of AlGaN/GaN high electron mobility transistor. Depending on the results, one can research the impact of the pressure to sensitive of pressure sensors on GaN.First of all, we described the prospect about the application of pressure sensors on GaN. It is a new material used to sensors. Due to the piezoelectric effect of GaN, we discussed piezoelectric effect the electron mobility. And under the impact of the pressure, the strain and stress can be changed by the external pressure increasing in crystal lattice. Based on Hooke’s law, the expression of piezoelectric effect in GaN was derived with the external pressure.Under the expression, the critical thickness as function of the external pressure and the relation between the critical thickness and misfit dislocation density was obtained. According to the research, one can draw the Ⅰ-Ⅴ curve by simulation, and we also know the change in the out-put current when the mobility is affected by the dislocation scattering. The studies show that the misfit dislocation scattering induced by the pressure is the main factor for the properties of high electron mobility transistor.We used analytic calculation and simulation to analyze the impact of the pressure on in-plane stress and strain in GaN, and the impact led to the change of mobility and output current. These studies provide a key factor to analyze the properties of the pressure sensors.Last, we can solve Schrodinger’s and Poisson’s equations by self consistently to obtain the potential energy of conduction band, wave function and sub-band energy levels of2DEG. And one also give the accurate Fermi energy by self consistently.