Open AccessAlGaN/GaN HEMTs on diamond substrate with over 7 W/mm output power density at 10 GHz
Author(s) -
Dumka D.C.,
Chou T.M.,
Faili F.,
Francis D.,
Ejeckam F.
Publication year - 2013
Publication title -
electronics letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.375
H-Index - 146
ISSN - 1350-911X
DOI - 10.1049/el.2013.1973
Subject(s) - materials science , diamond , optoelectronics , chemical vapor deposition , wafer , substrate (aquarium) , epitaxy , transistor , gallium nitride , dielectric , power density , power (physics) , layer (electronics) , electrical engineering , nanotechnology , metallurgy , voltage , oceanography , physics , engineering , quantum mechanics , geology
Record RF performance of AlGaN/GaN high electron mobility transistors (HEMTs) on a diamond substrate with over 7 W/mm output power density at 10 GHz is reported. It is achieved along with the peak power‐added‐efficiency over 46% and power gain over 11 dB for 2 × 100 µm gate‐width HEMTs at 40 V drain bias. Device wafers are prepared by first removing the host Si (111) substrate and nitride transition layers beneath the channel, depositing a 50 nm dielectric onto the exposed GaN buffer, and finally growing 100 µm of a chemical vapour deposition diamond onto the dielectric adhering to the epitaxial AlGaN/GaN. This approach enables the active GaN channel to be brought within 1 µm of the diamond substrate. Test HEMTs are fabricated using a dielectrically defined 0.25 µm gate length process.