Title :
Use of double-channel heterostructures to improve the access resistance and linearity in GaN-based HEMTs
Author :
Palacios, Tomás ; Chini, Alessandro ; Buttari, Dario ; Heikman, Sten ; Chakraborty, Arpan ; Keller, Stacia ; DenBaars, Steven P. ; Mishra, Umesh K.
Author_Institution :
Electr. & Comput. Eng. Dept., Univ. of California, Santa Barbara, CA, USA
fDate :
3/1/2006 12:00:00 AM
Abstract :
Double-channel structures have been used in AlGaN/GaN high electron mobility transistors to reduce the access resistance. Carrier densities as high as 2.9×1013 cm-2 and mobilities in the 1300 cm2/V·s range have been obtained in the access region. Also, the correct design of the potential barrier between the different channels allowed tailoring the differential access resistance to enhance the linearity of the transistors. This increase in linearity has been measured as a flatter profile of the transconductance and cutoff frequency versus current and as an improvement of more than 2 dB in large-signal two-tone linearity measurements.
Keywords :
III-V semiconductors; aluminium compounds; gallium compounds; high electron mobility transistors; AlGaN-GaN; current gain; cutoff frequency; differential access resistance; double-channel heterostructures; high electron mobility transistors; high-frequency performance; linearity measurements; potential barrier; transconductance characteristic; two-tone linearity; Aluminum gallium nitride; Charge carrier density; Current measurement; Electrical resistance measurement; Frequency measurement; Gallium nitride; HEMTs; Linearity; MODFETs; Transconductance; Current gain cutoff frequency; gallium nitride (GaN); high-electron mobility transistor (HEMT); high-frequency performance; transconductance; two-tone linearity;
Journal_Title :
Electron Devices, IEEE Transactions on
DOI :
10.1109/TED.2005.863767
