Evaluation of an InAlN/AlN/GaN HEMT with Ta-based ohmic contacts and PECVD SiN passivation
Journal article, 2014

An InAlN/AlN/GaN HEMT with Au-free Ta-based ohmic contacts and a high-quality PECVD SiN passivation is reported. The ohmic contacts were annealed at 550 degrees C, resulting in a contact resistance of 0.64 Omm. The gate length was 50 nm. The device performance and the process were evaluated by performing DC-, pulsed IV-, RF-, and load-pull measurements. It was observed that current slump was effectively mitigated by the passivation layer. The DC channel current density increased by 71 % to 1170 mA/mm at the knee of the IV curve, and the transconductance increased from 382 to 477 mS/mm after passivation. At the same time the gate leakage increased, and the extrinsic f(max) decreased from 207 to 140 GHz. Output powers of 4.1 and 3.5 W/mm were measured after passivation at 31 and 40 GHz, respectively.

Ta

passivation

InAlN

HEMT

ohmic contact

Author

Anna Malmros

Chalmers, Microtechnology and Nanoscience (MC2), Microwave Electronics

P. Gamarra

Thales Group

Mattias Thorsell

Chalmers, Microtechnology and Nanoscience (MC2), Microwave Electronics

M. A. di Forte-Poisson

Thales Group

C. Lacam

Thales Group

M. Tordjman

Thales Group

R. Aubry

Thales Group

Herbert Zirath

Chalmers, Microtechnology and Nanoscience (MC2), Microwave Electronics

Niklas Rorsman

Chalmers, Microtechnology and Nanoscience (MC2), Microwave Electronics

Physica Status Solidi (C) Current Topics in Solid State Physics

1862-6351 (ISSN) 1610-1642 (eISSN)

Vol. 11 3-4 924-927

Areas of Advance

Nanoscience and Nanotechnology

Subject Categories

Condensed Matter Physics

DOI

10.1002/pssc.201300320

More information

Latest update

10/17/2022