RF operation in graded Al x Ga1−x N (x = 0.65 to 0.82) channel transistors

T. Razzak; S. Hwang; A. Coleman; S. Bajaj; H. Xue; Y. Zhang; Z. Jamal-Eddine; S.H. Sohel; W. Lu; A. Khan; S. Rajan

RF operation in graded Al _x Ga_1−xN (x = 0.65 to 0.82) channel transistors

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Author(s): T. Razzak¹ ; S. Hwang² ; A. Coleman² ; S. Bajaj¹ ; H. Xue¹ ; Y. Zhang¹ ; Z. Jamal-Eddine¹ ; S.H. Sohel¹ ; W. Lu¹ ; A. Khan² ; S. Rajan¹
- Affiliations: 1: ECE Department, The Ohio State University , Columbus, OH 43210 , USA ;
  2: Department of EE, University of South Carolina , 301 Main Street, Columbia, SC 29208 , USA
Source: Volume 54, Issue 23, 15 November 2018, p. 1351 – 1353
DOI: 10.1049/el.2018.6897 , Print ISSN 0013-5194, Online ISSN 1350-911X

Received 11/09/2018, Published 15/10/2018

The first report is presented on the RF operation of AlGaN channel transistor with Al-composition above 80%. The reported device is a polarisation-graded field effect transistor (PolFET) featuring an ultra-wide bandgap (UWBG) AlGaN channel with Al-composition grading from 65 to 82%. Transistors with a gate length of 0.8 μm were fabricated, with a current density of 265 mA/mm, the highest observed for AlGaN channel transistor with Al-composition above 80%, and f _T/f _MAX of 5.4/14.2 GHz. This demonstration of RF operation of polarisation-graded transistor provides a direction for achieving ultra-wide bandgap AlGaN based devices for high performance RF and power switching applications.

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high metal channel

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RF operation in graded Al _x Ga_1−xN (x = 0.65 to 0.82) channel transistors

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