Growth of quaternary InAlGaN barrier with ultrathin thickness for HEMT application. (June 2018)

• Record Type: Journal Article
• Authors: Li, Zhonghui; Li, Chuanhao; Peng, Daqing; Zhang, Dongguo; Dong, Xun; Pan, Lei; Luo, Weike; Li, Liang; Yang, Qiankun
• Is Part Of: Superlattices and microstructures. Volume 118(2018)
• Page Start: 213
• Page End: 220
• Publication Date: 2018-06
• Subjects: AlInGaN -- InAlGaN -- HEMT -- Growth mechanism -- MOCVD; Superlattices as materials -- Periodicals; Microstructure -- Periodicals; Semiconductors -- Periodicals; Superréseaux -- Périodiques; Microstructure (Physique) -- Périodiques; Semiconducteurs -- Périodiques; 621.38152
• DOI: 10.1016/j.spmi.2018.04.022
• Languages: English
• ISSNs: 0749-6036

Abstract

Abstract: Quaternary InAlGaN barriers with thickness of 7 nm for HEMT application were grown on 3-inch semi-insulating 4H-SiC substrates by metal organic chemical vapor deposition (MOCVD). Focused on growth mechanism of the InAlGaN barrier, the surface morphology and characteristics of InAlGaN/AlN/GaN heterostructures were studied with different growth parameters, including the temperature, Al/Ga ratio and chamber pressure. Among the as-grown samples, high electron mobility is consistent with smooth surface morphology, while high crystalline quality of the quaternary barrier is confirmed by measurements of Photoluminescence (PL) and Mercury-probe Capacity-Voltage (C-V). The recommended heterostructures without SiN passivation is characterized by mobility of 1720 cm 2 /(V·s), 2DEG density of 1.71*10 13 cm −2, sheet resistance of about 210 Ω/□ with a smooth surface morphology and moderate tensile state, specially applied for microwave devices. Highlights: The growth of InAlGaN/AlN/GaN heterostructures was performed on 3inch 4H-SiC substrates by MOCVD. The growth mechanism of the ultrathin InAlGaN barrier was studied in detail with different growth parameters. High crystalline-quality InAlGaN barriers were achieved with low density of defects and smooth surface morphology. The surface morphology is related with thesurface mobility of atoms, strain and prereactions of TMAl with ammonia. Electron mobility of 1720 cm 2 /(V·s), 2DEG density of 1.71*10 13 cm -2 and smooth surface morphology are obtained.