(Raw Data Set) Polarization effects in ferroelectric gate AlGaN/GaN High Electron Mobility Transistors

Abstract

The impact of polarization effects induced by a ferroelectric layer on the on-state performance of ferroelectric gate AlGaN/GaN HEMTs has been studied by using experiments and extensive TCAD simulations. Stress-free and high quality crystalline (111) lead-zirconate-titanate (Pb(ZrxTi1-x)O-3 or PZT) films on top of GaN have been successfully obtained by adopting a single magnesium-oxide (MgO) monolayer as a buffer layer. By adjusting the zirconium composition (x) of PZT, solely the spontaneous polarization in PZT is varied. In addition a onedimensional electrostatic model has been derived showing the impact of the polarization in the ferroelectric gate on the 2DEG sheet density and threshold voltage (V-TH), which is in good agreement with TCAD simulations. The experimental data show for x = 0.20 a minimum on-resistance (R-ON) of similar to 9.7k Omega and for x = 0.52 a minimal V-TH of similar to -3.3V. The results are important for providing a guide line to optimize ferroelectric gate AlGaN/GaN HEMTs.