Bendable Microwave AlGaN/GaN High-Electron-Mobility Transistor With Output Power Density of 2.65 W/mm

• Published in: IEEE electron device letters Vol. 42; no. 5; pp. 677 - 680
• Main Authors: Wang, Yan, Wu, Qingzhi, Mao, Shuman, Xu, Ruimin, Yan, Bo, Xu, Yuehang
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.05.2021; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Aluminum gallium nitrides; Bend radius; Bendable; Bending machines; Electronics; Gallium nitride; Gallium nitrides; HEMTs; High electron mobility transistors; high-electron-mobility-transistor; Maximum power; microwave; Power generation; Radio frequency; Semiconductor devices; Silicon; Silicon carbide; Silicon substrates; Strain; Substrates; Transistors; Wide band gap semiconductors; Wireless communication systems; Wireless communications
• ISSN: 0741-3106; 1558-0563
• DOI: 10.1109/LED.2021.3068738

Flexible radio frequency (RF) devices are in high demand for wearable electronics; however, they currently do not offer sufficient output power for application in fifth-generation wireless communication systems. This paper reports a bendable gallium nitride (GaN) high-electron-mobility-transistor (HEMT) with state-of-the-art output power in the microwave band. In this study, a fabrication method is proposed, where HEMT is originally grown on silicon carbide (SiC) substrates. After thinning the SiC substrates down to <inline-formula> <tex-math notation="LaTeX">5~\mu \text{m} </tex-math></inline-formula>, HEMT is transferred using a copper film rather than flexible substrates used in other studies. The measurements indicated that the fabricated devices exhibited a saturation output power of 2.65 W, corresponding to a power density of 2.65 W/mm, which was associated with maximum power added efficiency (PAE) of 51% at 3 GHz. The performance of the fabricated device remained stable even with a bending radius of up to 0.6 cm. These results indicated that the proposed fabrication method can potentially be used to realize high-power flexible RF electronics.