No abstract

No abstract

The impact of fast electron exposure upon the performance of commercial silicon carbide Schottky diodes has been studied. Under 3 MeV electrons, absorbed dose of 10 and 15 MGy at room temperature, the forward current density-voltage characteristic of INFINEON and STMICROELECTRONICS devices have been decreased by 4.6 and 8.2 orders of magnitude respectively. The reduction is associated with the significant rise in the series resistance (INFINEON: 1.45 Ω to 121×10 Ω; STMICROELECTRONICS: 1.44 Ω to 2.1 × 10 Ω) due to the irradiation-induced defects. Besides that, the reverse leakage current density in INFINEON increased by one order of magnitude while reverse leakage current density in STMICROELECTRONICS decreased by about one order of magnitude. We have also observed an increase in ideality factor (INFINEON: 1.01 to 1.05; STMICROELECTRONICS: 1.02 to 1.3) and saturation current (INFINEON: 1.6×10 A to 2.5×10 A; STMICROELECTRONICS: 2.4×10 A to 8 × 10 A) as a result of electron irradiation. Overall, for particular devices studied, INFINEON have better quality devices and more radiation resistance compared to STMICROELECTRONICS.

In this paper the effects of high energy (3.0 MeV) electrons irradiation over a dose ranges from 6 to 15 MGy at elevated temperatures 298 to 448 K on the current-voltage characteristics of 4H-SiC Schottky diodes were investigated. The experiment results show that after irradiation with 3.0 MeV forward bias current of the tested diodes decreased, while reverse bias current increased. The degradation of ideality factor, n, saturation current, I , and barrier height, Φ , were not noticeable after the irradiation. However, the series resistance, R , has increased significantly with increasing radiation dose. In addition, temperature dependence current-voltage measurements, were conducted for temperature in the range of 298 to 448 K. The Schottky barrier height, saturation current, and series resistance, are found to be temperature dependent, while ideality factor remained constant.The article is published in the original.

Half-wave rectifier; buck; and boost converter with electron-irradiated, highvoltage silicon carbide Schottky power diodes from CREE, Inc., performance was studied and presented in this paper subjected to electron radiation. The diodes were irradiated by high-energy (3 MeV) electrons with doses ranging from 1 to 5 MGy. The performance of the circuits in term of the output voltage were measured before and after the diodes being irradiated. It was observed, at 4 MGy, the half-wave rectifier output voltage degrades by 6.2 times as compared to before irradiation. Meanwhile, the output voltage of the buck converter degrades by 1.7 times; and for boost converter, the degradation of the output voltage is approximately 4.6 times for 4MGy radiation. These degradations are believed to be due to the increase in the series resistance of the Schottky diodes which is caused by the defects introduced inside the semiconductor during the irradiation and also the increase of turn-on voltage of the diodes after being irradiated.