Enhancing Reliability and RF Performance: The Impact of Fe Doped Back Barrier Optimization in GaN HEMTs

In this paper, we investigate the impact of the Fe doped back barrier thickness (T <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">bb</inf> ) on AlGaN/GaN HEMT device. The Fe doping on back barrier significantly improves the electric field and 2DEG charge density of the GaN HEMT device. The Fe doping on AlGaN back barrier with Fe concentration of 1 × 10 17 cm 3 and thickness T <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">bb</inf> of 1 μm, 1.5 μm and 2 μm. The electric field and 2DEG charge density are analyzed by varying the Fe doped back barrier thickness. The device breakdown performance significantly improves up to 70% and the radio frequency RF performance improves up to 50% on a 60 nm gate length L <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">G</inf> device. This improved device performance is highly capable for high frequency RF communication applications.