Very High Sustainable Forward Current Densities on 4H-SiC p-n Junctions Formed by VLS Localized Epitaxy of Heavily Al-Doped p⁺⁺ Emitters

Selsabil Sejil (1) , Loïc Lalouat (2) , Mihai Lazar (3) , Davy Carole (1) , Christian Brylinski (1) , François Jomard (4) , Dominique Planson (3, 5) , Gabriel Ferro (1) , Christophe Raynaud (3, 5)

1 LMI - Laboratoire des Multimatériaux et Interfaces
2 ICB - Laboratoire Interdisciplinaire Carnot de Bourgogne
3 EE - Ampère, Département Energie Electrique
4 GEMAC - Groupe d'Etude de la Matière Condensée
5 INSA Lyon - Institut National des Sciences Appliquées de Lyon

This study deals with the electrical characterization of PiN diodes fabricated on a 4°off-axis 4H-SiC n+ substrate with a n- epilayer (1×1016 cm-3 / 10 µm). Optimized p++ epitaxial areas were grown by Vapour-Liquid-Solid (VLS) transport to form p+ emitters localized in etched wells with 1 µm depth. Incorporated Al level in the VLS p++ zones was checked by SIMS (Secondary Ion Mass Spectroscopy), and the doping level was found in the range of 1-3×1020 at.cm-3. Electrical characterizations were performed on these PiN diodes, with 800 nm deposit of aluminium as ohmic contact on p-type SiC. Electrical measurements show a bipolar behaviour, and very high sustainable forward current densities ≥ 3 kA.cm-2, preserving a low leakage current density in reverse bias. These measurements were obtained on structures without any passivation and no edge termination.

Mots clés: Silicon Carbide (SiC); Vapor Liquid Solid (VLS); p++ Doping; p-n Junction; SiC; VLS; selective epitaxy; roughness; p-type ohmic contact

Domaines: Energie électrique

Selsabil Sejil, Loïc Lalouat, Mihai Lazar, Davy Carole, Christian Brylinski, et al.. Very High Sustainable Forward Current Densities on 4H-SiC p-n Junctions Formed by VLS Localized Epitaxy of Heavily Al-Doped p⁺⁺ Emitters. Materials Science Forum, 2017, 897, pp.63 - 66. ⟨10.4028/www.scientific.net/MSF.897.63⟩. ⟨hal-01648360⟩