A theoretical investigation on the effect of "AlN interlayer" on two-dimensional electron gas mobility and electronic properties in AlInN/GaN heterostructures

In this paper, we have theoretically studied the temperature dependent (77–600 K) of electrical transport of two-dimensional electron gas (2DEG) in Al0.83In0.17N/GaN heterostructure in two conditions: with and without “interlayer”. The results of our analysis based on various scattering mechanisms and Matthiessen’s rule indicate that in sample with interlayer the dislocation density has decreased to about 2.8 times compare with another sample without interlayer and this in turn has led to raise the 2DEG mobility in the former sample. Also considering the reported data at 77 K related to the 2D electron gas density, which shows it is higher in sample with interlayer, we tried to analyze these data on the basis of Fermi-Dirac statistics. We found that increasing the electron density in the well will tend to decrease the width of the well and therefore increase the internal electric field. These variations also change the position of electronic levels and the Fermi level inside the well.