Title :
0.2- mu m gate-length atomic-planar doped pseudomorphic Al/sub 0.3/Ga/sub 0.7/As/In/sub 0.25/Ga/sub 0.75/As MODFETs with f/sub T/ over 120 GHz
Author :
Nguyen, Loi D. ; Radulescu, David C. ; Tasker, Paul J. ; Schaff, William J. ; Eastman, Lester F.
Author_Institution :
Sch. of Electr. Eng. & Nat. Nanofabrication Facility, Cornell Univ., Ithaca, NY, USA
Abstract :
The authors report the DC and RF performance of nominally 0.2- mu m-gate length atomic-planar doped pseudomorphic Al/sub 0.3/Ga/sub 0.7/As/In/sub 0.25/Ga/sub 0.75/As modulation-doped field-effect transistors (MODFETs) with f/sub T/ over 120 GHz. The devices exhibit a maximum two-dimensional electron gas (2 DEG) sheet density of 2.4*10/sup 12/ cm/sup -2/, peak transconductance g/sub m/ of 530-570 mS/mm. maximum current density of 500-550 mA/mm, and peak current-gain cutoff frequency f/sub T/ of 110-122 GHz. These results are claimed to be among the best ever reported for pseudomorphic AlGaAs/InGaAs MODFETs and are attributed to the high 2 DEG sheet density, rather than an enhanced saturation velocity, in the In/sub 0.25/Ga/sub 0.75/As channel.<>
Keywords :
III-V semiconductors; aluminium compounds; gallium arsenide; high electron mobility transistors; indium compounds; 0.2 micron; 110 to 122 GHz; AlGaAs-InGaAs; DC; MODFETs; RF performance; atomic-planar doped; current density; maximum two-dimensional electron gas; modulation-doped field-effect transistors; peak current-gain cutoff frequency; peak transconductance; sheet density; Current density; Cutoff frequency; Electrons; Epitaxial layers; FETs; HEMTs; Indium gallium arsenide; MODFETs; Radio frequency; Transconductance;
Journal_Title :
Electron Device Letters, IEEE
