DLTFS investigation of electron traps on AlGaN/GaN on Si Power diodes

Florian Rigaud-Minet (1, 2) , Christophe Raynaud (1) , Julien Buckley (2) , Matthew Charles (2) , Patricia Pimenta-Barros (2) , Romain Gwoziecki (2) , Charlotte Gillot (2) , Véronique Sousa (2) , Hervé Morel (1) , Dominique Planson (1)

1 INSA - Institut National des Sciences Appliquées
2 CEA-LETI - Commissariat à l'énergie atomique et aux énergies alternatives - Laboratoire d'Electronique et de Technologie de l'Information

Many kinds of defects are present in AlGaN/GaN on Si based power electronics devices. Their identification is the first step to understand and improve device performance. Electron traps are investigated in AlGaN/GaN on Si power diodes using Deep Level Transient Fourier Spectroscopy (DLTFS) at different bias conditions. This study reveals seven different traps corresponding to point defects. Their energy level $E_T$ ranged from 0.4 eV to 0.57 eV below the conduction band. Among them, two new traps are reported and are etching-related: D3 ($E_T$ = 0.47 0.48 eV; σ ≈ 10 15 cm²) and D7 ($E_T$ = 0.57 eV; σ = 4.45x10 12 cm²). The possible origin of the other traps are discussed with respect to the GaN literature. They are proposed to be related to carbon and nitrogen vacancies or to carbon such as CN-CGa. Some others are likely due to crystal surface recombination, native defects or related complex or to nitrogen antisite: NGa.

Mots clés: power electronics; wide bandgap; gallium nitride; DLTS; reactive ion etching; traps

Domaines: Micro et nanotechnologies/Microélectronique

Florian Rigaud-Minet, Christophe Raynaud, Julien Buckley, Matthew Charles, Patricia Pimenta-Barros, et al.. DLTFS investigation of electron traps on AlGaN/GaN on Si Power diodes. Energies, 2022, 16, pp.599. ⟨10.3390/en16020599⟩. ⟨cea-03968526⟩