Low-Temperature Annealing of Radiation-Induced Degradation in 4H-SiC Bipolar Junction Transistors

Radiation hardness is tested for 4H-SiC n-p-n bipolar junction transistors designed for 1200-V breakdown voltage by implanting MeV protons and carbon ions at different doses and energies. The current gain is found to be a very sensitive parameter, and a fluence as low as 1 × 10<sup>7</sup> cm<sup>-2</sup> of 10 MeV <sup>12</sup>C can be clearly detected in the forward-output characteristics, I<sub>C</sub>(V<sub>CE</sub>) . At this low dose, no influence of ion radiation is seen in the open-collector characteristics, I<sub>B</sub>(V<sub>EB</sub>), or the reverse bias leakage and breakdown properties. Moreover, by annealing the implanted devices at 420°C for 30 min, a complete recovery of the electrical characteristics is accomplished.

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