Polarization Engineering of AlGaN/GaN HEMT With Graded InGaN Sub-Channel for High-Linearity X-Band Applications

• Published in: IEEE electron device letters 2019-04, Vol.40 (4), p.522-525
• Main Authors: Sohel, Shahadat H., Xie, Andy, Beam, Edward, Xue, Hao, Razzak, Towhidur, Bajaj, Sanyam, Cao, Yu, Lee, Cathy, Lu, Wu, Rajan, Siddharth
• Format: Article
• Language: English
• Subjects: Aluminum gallium nitride; Aluminum gallium nitrides; composite 2D-3D channel; Figure of merit; Gallium nitrides; graded InGaN channel; HEMTs; Indium gallium nitrides; Linearity; Logic gates; Metalorganic chemical vapor deposition; Organic chemicals; Organic chemistry; Polarization; polarization-graded field-effect transistor; Power gain; Semiconductor devices; Superhigh frequencies; Three dimensional composites; Transconductance; Transistor linearity; Transistors; Two dimensional composites; two-tone linearity; Wide band gap semiconductors
• ISSN: 0741-3106; 1558-0563
• DOI: 10.1109/LED.2019.2899100

We report on the power and linearity performance of metal-organic chemical vapor deposition grown polarization-engineered novel structure that combines the AlGaN/GaN high-electron-mobility transistor with a graded InGaN sub-channel layer. The fabricated transistors with composite two-dimensional(2D) and three-dimensional(3D) electron channels showed nearly flat transconductance and power gain profiles. The maximum f T and f max values of 18 GHz and 38 GHz were measured for 0.7-μm gate-length transistors. Load-pull measurement at 10 GHz revealed a maximum output power of 2.2 W/mm. Two-tone measurement at 10 GHz showed an excellent OIP3 of 38 dBm for 150-μm device width and a corresponding linearity figure of merit OIP3/P DC of 9.7 dB. These results suggest that InGaN-based composite 2D-3D channel transistors could be useful for high-frequency applications requiring high linearity.