We report the first quantum-well doped p-channel AlGaAs/GaAs0.85Sb0.15/GaAs Heterostructure Field-Effect Transistor (HFET's) with 50-mu-m gate length and 400-mu-m gate width. Using a simple analytical model, we obtain accurate values of the low-field hole mobility, threshold voltage, parameters characterizing the gate leakage current, and the saturation currents and voltages. The calculation results are in good agreement with the experimental data.