Fabrication and characterization of GaN HEMTs grown on SiC substrates with different orientations. (May 2021)

• Record Type: Journal Article
• Authors: Su, Chung-Wang; Wang, Tong-Wen; Wu, Meng-Chyi; Ko, Cheng-Jung; Huang, Jun-Bin
• Is Part Of: Solid-state electronics. Volume 179(2021)
• Publication Date: 2021-05
• Subjects: Semiconductors -- Periodicals; Semiconducteurs -- Périodiques; 621.38152
• DOI: 10.1016/j.sse.2021.107980
• Languages: English
• ISSNs: 0038-1101

Abstract

Highlights: AlGaN/GaN HEMTs Grown on SiC Substrates with Different Orientations. The 4°-off SiC substrates, drain saturation current density (JDS, max ) of 1016 mA/mm for MIS-HEMT. The 4°-off SiC substrates better than those with 0° SiC substrates. Abstract: This article reports the fabrication and characterization of metal–semiconductor high electron mobility transistors (MS-HEMT) and metal–oxidesemiconductor (MIS-HEMT) grown on the semi-insulating SiC substrates with 0° and 4°-off axis. For the MIS-HEMT, the HfO2 film was used as the insulator deposited by atomic layer deposition. With a gate length of 2 μm, MS-HEMT and MIS-HEMT devices with 4°-off SiC substrates exhibit a drain saturation current density (JDS, max ) of 895 and 1016 mA/mm, the maximum transconductance (Gm, max ) of 225 and 175 mS/mm, a cut-off frequency (fT ) of 8.1 and 9.4 GHz, and a maximum oscillation frequency (fmax ) of 22 and 27.4 GHz, respectively, which are better than those with 0° SiC substrates. Furthermore, the devices with 4°-off substrate are verified with less interface states and buffer traps through the temperature-dependent and pulse current–voltage measurements.