Radiation-induced defects in SiC-MESFETs after 2-MeV electron irradiation

• Published in: Physica. B, Condensed matter Vol. 376; pp. 382 - 384
• Main Authors: Ohyama, H., Takakura, K., Uemura, K., Shigaki, K., Kudou, T., Arai, M., Kuboyama, S., Matsuda, S., Kamezawa, C., Simoen, E., Claeys, C.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.04.2006
• Subjects: Induced deep levels; Radiation damage; SiC-MESFET; 61.72; 61.82; SiC-MESFET; Induced deep levels; 61.80; Radiation damage
• ISSN: 0921-4526; 1873-2135
• DOI: 10.1016/j.physb.2005.12.098

The impact of radiation damage on the device performance of 4H-SiC metal Schottky field effect transistors, which are irradiated at room temperature with 2-MeV electrons, is studied. No performance degradation is observed by 1 × 10 15 e / cm 2 , while a slight increase of the linear drain current together with a decrease of the threshold voltage are noticed for 1 × 10 16 e / cm 2 . The degradation for low electron fluence is mainly attributed to the radiation-induced decrease of the Schottky barrier height at the gate contact. For exposures over 1 × 10 16 e / cm 2 , the drain current and transconductance decrease. The maximum transconductance for 1 × 10 17 e / cm 2 is only 18% of the value before irradiation. Although no electron capture levels are observed before irradiation, three electron capture levels ( E 1 – E 3 ) are induced after irradiation. The observed increase of the channel resistance is due to the induced lattice defects creating electron traps.