Epitaxial optimization of 130 nm gate-length InGaAs/InAlAs/InP HEMTs for low-noise applications
Journal article, 2009

The epitaxial structure of 130-nm gate-length InGaAs/InAlAs/InP high electron mobility transistors (HEMTs)has been studied in order to optimize the device performance when biased under low-noise conditions. Three essential epitaxial parameters have been varied: the In channel content ([In]: 53%, 70%, and 80%), the δ-doping concentration (δ: 3, 5, and 7 × 1E12 cm−2), and the Schottky layer thickness (dSL: 9, 11, and 13 nm). All HEMTs exhibited low gate-leakage current IG below 1 μA/mm at a low-noise bias, except dSL = 9 nm due to a too thin Schottky layer thickness. It was verified that the lowest noise figure NF was achieved when the square root of the drain-to-source current IDS over transconductance gm exhibited a minimum. A clear optimum for both dSL and δ was observed with respect to minimum noise figure NFmin. Increasing [In] only provided a slight reduction in NFmin. In contrast, the RF performance was much more affected by increasing [In]. The lowest NFmin was achieved with a δ doping of 5 × 1E12 cm−2 and a dSL of 11 nm.



low noise


Mikael Malmkvist

Chalmers, Microtechnology and Nanoscience (MC2), Microwave Electronics

Shu Min Wang

Chalmers, Microtechnology and Nanoscience (MC2), Microwave Electronics

Jan Grahn

Chalmers, Microtechnology and Nanoscience (MC2), Microwave Electronics

IEEE Transactions on Electron Devices

0018-9383 (ISSN) 15579646 (eISSN)

Vol. 56 1 126-131

Subject Categories

Other Electrical Engineering, Electronic Engineering, Information Engineering



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