AlGaN channel HEMTs on AlN buffer layer with sufficiently low off-state drain leakage current

Adv. Technol. R&D Center, Mitsubishi Electr. Corp., Amagasaki, Japan
Electronics Letters (Impact Factor: 0.93). 01/2010; 45(25):1346 - 1348. DOI: 10.1049/el.2009.2711
Source: IEEE Xplore


The buffer layer in AlGaN channel HEMTs to suppress the off-state drain leakage current is investigated. By employing an AlN for the buffer layer in Al0.39Ga0.61N/Al0.16Ga0.84N HEMTs, the off-state drain leakage current was sufficiently suppressed and the breakdown voltage was enhanced. It was considered that employing the AlN for the buffer layer is important for extracting the superior material properties of the AlGaN in the channel layer.

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