Open AccessAlN/Al0.5Ga0.5N HEMTs with heavily Si-doped degenerate GaN contacts prepared via pulsed sputtering
Author(s) -
Ryo Maeda,
K. Ueno,
Atsushi Kobayashi,
Hiroshi Fujioka
Publication year - 2022
Publication title -
applied physics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.911
H-Index - 94
eISSN - 1882-0786
pISSN - 1882-0778
DOI - 10.35848/1882-0786/ac4fcf
Subject(s) - ohmic contact , transconductance , materials science , doping , optoelectronics , sputtering , contact resistance , transistor , high electron mobility transistor , degenerate energy levels , analytical chemistry (journal) , layer (electronics) , nanotechnology , thin film , chemistry , electrical engineering , voltage , physics , engineering , quantum mechanics , chromatography
This paper reports AlN barrier Al 0.5 Ga 0.5 N high electron mobility transistors (HEMTs) with heavily Si-doped degenerate GaN contacts prepared by pulsed sputtering deposition. Selectively regrown n-type GaN contacts exhibit typical degenerate properties with the electron concentration and mobility of 2.6 × 10 20 cm −3 and 115 cm 2 V −1 s −1 , respectively, resulting in a record low contact resistance R C of 0.43 Ω mm for the AlN/Al 0.5 Ga 0.5 N HEMTs. The AlN/Al 0.5 Ga 0.5 N HEMTs displayed a remarkable DC output characteristic with a maximum drain current density of 250 mA mm −1 , a transconductance of 32 mS mm −1 , and an On/Off ratio >10 6 . The present results show potential overcoming challenges in ohmic contact formation for high-power and high-frequency AlGaN electron devices with high Al composition.