Abstract: The vertical GaN/AlGaN hetero-junction field-effect transistors (HFETs) can be widely used as high-power switching devices, etc.However, the device performance are constrained by the trade-off between breakdown voltage (V_B) and specific on-resistance (R_{on, sp}), which are worth further research.Herein, an enhanced vertical HFET integrated with GaN/Al_x1(x2)Ga_1-x1(x2)N dual hetero-junction (HJ) source and (n) GaN/(p₁₍₂₎) Al_x3(x4)Ga_1-x3(x4)N/(n) GaN stacked hetero-semi-super-junction (HSSJ) is proposed.The effects of the Al compositions (x₁, x₂, x₃, x₄), the width (W_p) of (p) AlGaN pillar, the doped level (N_CBL) in current barrier layer (CBL) on the device static performance are simulated by using the Silvaco TCAD software.The results imply that more 2DEGs can be output from the dual HJ source with suitable (x₁and x₂), which yields large drain current density (J_DS) and low R_{on, sp}.The electric field distribution and carrier path can be optimized by adjusting the Al compositions (x₃and x₄) in the HSSJ, which results in high V_B and low R_{on, sp}.The R_{on, sp} of the proposed device decreased by 39.33% while the power figure of merit (FOM_BR) increased by 46.15% comparing to a non-uniformly doped homo-full-super-junction vertical HFET DOI: 10.1088/1674-1056/27/4/047305.This paper can provide a new scheme for designing high performance HFETs.