Extraction of the 4H-SiC/SiO₂ Barrier Height Over Temperature

Oriol Aviño Salvado (1) , Besar Asllani (1) , Cyril Buttay (1) , Christophe Raynaud (1) , Hervé Morel (1)

1 EE - Ampère, Département Energie Electrique

The behaviour of the barrier height of the SiC/SiO 2 interface has been investigated over a wide temperature range, from 173 to 523 K. These data complement literature, providing a better knowledge of this parameter, which was studied only over a more restricted temperature range, and never before for low temperatures. It is highlighted that measured samples exhibit a barrier height temperature dependence very near to the theoretical one (≈−0.7 meV K −1). Beyond 473 K the barrier height seems to drop faster for some samples, reaching ≈−1.4 meV K −1. Should this faster decreasing rate be maintained for higher temperatures, it could limit 4H-SiC MOSFETs performances or reliability for high temperature applications. It is expected that the data provided here will allow for a more accurate modelling of the gate current and of the charge injection in the oxide layer of power MOSFETs, leading to more reliable predictions of the oxide lifetime for 4H-SiC MOSFETs.

Mots clés: Barrier height; SiC/SiO 2; Temperature; Fowler- Nordheim; Oxide; Robustness

Domaines: Energie électrique

Oriol Aviño Salvado, Besar Asllani, Cyril Buttay, Christophe Raynaud, Hervé Morel. Extraction of the 4H-SiC/SiO₂ Barrier Height Over Temperature. IEEE Transactions on Electron Devices, 2019, 67 (1), pp.63 - 68. ⟨10.1109/TED.2019.2955181⟩. ⟨hal-02418097⟩