Theoretical investigation of wurtzite crystal-based vertical p–n diodes with dopant-free distributed polarization doping

An analytical model for AlGaN-based distributed polarization doping (DPD) p–n diodes is developed, integrating temperature-dependent lifetimes and thermionic-field emission effects. Validated against experimental data from Kumabe et al., IEEE Trans. Electron Devices 71, 3396 (2024), the model captures the conduction transition from Shockley–Read–Hall-recombination-dominated to drift-dominated transport at the moderate temperature. We quantitatively define the depletion approximation's validity and demonstrate the DPD structure's capability to decouple carrier mobility from injection efficiency. This framework provides a rigorous foundation for optimizing polarization-engineered wide-bandgap power electronics across a wide temperature range.