Effect of AlGaN Back Barrier on InAlN/AlN/GaN E-Mode HEMTs

This paper reports the effect of AlGaN back barrier on the performance of lattice matched In0.17Al0.83N/AlN/GaN Recess Gate E HEMT Device. The use of AlGaN back barrier on this device relaxes the GaN channel, which in turn limits the SCEs. Moreover reduced the leakage current through gate (Ig) and simultaneously improves carrier confinement and off state breakdown voltage. The numerical modeling are carried out with the help of 2D Sentaurus TCAD simulator using Hydrodynamic model, which is standardized with respect to already published fabricated results. Different performance parameters are studied using the simulations and a wide comparison was done with and without considering AlGaN back barrier (BB). Addition of AlGaN BB has added benefits in performance parameters w.r.t without BB i.e. threshold voltage raised to 0.93 volt with respect to 0.75 volt, drop in DIBL from 100mv/V to 36mv/V and substantial reduction in gate leakage current. These results reveal that use of AlGaN BB in such devices can be an alternative solution for high power and high frequency switching applications.