Performance of gamma irradiated p-channel 6H-SiC MOSFETs: high total dose

We present the first observation of total dose effects of gamma-ray irradiation on enhancement mode 6H-SiC p-channel MOSFETs. The electrical characterization of these transistors was performed before and after irradiation up to a total dose of 10⁸ rad (SiO₂) by measuring the drain-source current (I_ds) as a function of gate voltage (V_g) and drain-source voltage (V_ds). These transistors were compared to 6H-SiC n-channel MOSFETs. The p-channel devices remain fully functional up to 10⁶ rad (SiO₂), while the n-channel devices are fully functional through 10⁸ rad (SiO₂). We found that the generation of radiation-induced interface states in the n-channel transistors is substantially lower than that of the p-channel devices.