Study of 6H-SiC high voltage bipolar diodes under reverse biases

Karine Isoird (1, 2) , Mihai Lazar (1, 2) , Laurent Ottaviani (1, 2) , Marie-Laure Locatelli (1, 2) , Christophe Raynaud (1, 2) , Dominique Planson (1, 2, 3) , Jean-Pierre Chante (1, 2)

1 CEGELY - Centre de génie électrique de Lyon
2 INSA Lyon - Institut National des Sciences Appliquées de Lyon
3 EE - Ampère, Département Energie Electrique

Silicon carbide presents electrical properties suitable for many applications especially for high voltage devices. 6H-SiC P+NN+ structures have been fabricated following ISE software simulations in order to block voltages as high as 1.5 kV. In particular, these diodes are realized by surrounding the emitter by a p-type region called junction termination extension (JTE). Electrical characterizations under reverse bias at, room temperature and in various environments (air, silicone oil) show a premature breakdown for the protected diodes. This breakdown is localized at the emitter periphery. Optical beam induced current (OBIC) measurements show a peak of photocurrent at the junction edge, indicating the presence of a high electric field. These results show a protection efficiency of 60% of the JTE. An electrical activation of the aluminum dopants implanted in the JTE around 30% is derived from the analysis of the presented results.

Mots clés: JTE; OBIC; 6H-SiC; Bipolar diodes; Breakdown voltage; JTE _______________________________________________________________________________

Domaines: Energie électrique

Karine Isoird, Mihai Lazar, Laurent Ottaviani, Marie-Laure Locatelli, Christophe Raynaud, et al.. Study of 6H-SiC high voltage bipolar diodes under reverse biases. Applied Surface Science, 2001, 184 (1-4), pp.477-482. ⟨10.1016/S0169-4332(01)00537-2⟩. ⟨hal-00140118⟩