[18a-Z05-1~11] 15.6 Group IV Compound Semiconductors (SiC)

▲ [18a-Z05-8] Improve High-Temperature Reliability at 500℃ of Ni/Nb/4H-SiC Ohmic Contact
with CF₄:O₂ Surface Treatment

〇Cuong Van Vuong¹, Seiji Ishikawa^1,2, Tomonori Maeda^1,2, Hiroshi Sezaki^1,2, Tetsuya Meguro¹, Tadashi Sato¹, Shin-Ichiro Kuroki¹ (1.Research Institute for Nanodevice and Bio Systems, Hiroshima University, 2.Phenitec Semiconductor Corp)

Keywords:Ohmic contact, high temperature reliability, Silicon Carbide, Ni/Nb, CF4:O2 etching

In this research, the high temperature stability of the Ni/Nb/4H-SiC ohmic contact at 500℃ with and without CF₄:O₂ surface treatment was investigated. After the fabrication process, the extracted specific contact resistance of the sample with and without CF₄:O₂ treatment was 1.0×10⁻³ Ω.cm², and 1.6×10⁻³ Ω.cm², respectively. In order to investigate the high-temperature reliability, the samples were aged at 500℃ in N₂ ambient. Based on the I-V curves of the Ni/Nb/4H-SiC contact with and without surface treatment after different duration of aging time, it has showed that, just after 25-hour aging at 500℃, the sample without the surface treatment lost the ohmic behavior. Whereas, the sample with CF₄:O₂ surface etching shows a good stability up to after 100 hours of aging. This result shows that the Ni/Nb/4H-SiC ohmic contact with CF₄:O₂ surface treatment could be a potential candidate for harsh environment applications.