Title :
Influence of quantum well width on DC and RF device performance in pseudomorphic Al0.30Ga0.70As/In0.25Ga 0.75As MODFETs
Author :
Nguyen, L.D. ; Radulescu, D.C. ; Tasker, P.J. ; Foisy, M.C. ; Eastman, L.F.
Author_Institution :
Sch. of Electr. Eng., Cornell Univ., Ithaca, NY
fDate :
12/1/1988 12:00:00 AM
Abstract :
An experimental study of the influence of quantum well width on DC and RF device performance in nominally 0.2-μm gate-length atomic-planar doped pseudomorphic Al0.30Ga0.70As/In0.25Ga0.75 As MODFETs is reported. Three important results have been obtained: (1) a well width of ~120 Å appears to be optimum for overall device performance and gives a current gain cutoff frequency ( fT) of 122 GHz; (2) thinner quantum wells (~45 Å) result in a significant reduction (~40%) in maximum channel current density; and (3) thicker quantum wells (150-200 Å), which exceed the critical thickness (90-100 Å) predicted by the Matthews and Blakeslee model, still give excellent device performance (f T=107 GHz). As a result of the latter, it might be possible to realize much higher-indium-percentage (30-40%) quantum wells without having to reduce the well width to an unacceptable value
Keywords :
III-V semiconductors; aluminium compounds; gallium arsenide; high electron mobility transistors; indium compounds; semiconductor quantum wells; semiconductor technology; solid-state microwave devices; 107 to 122 GHz; 200 nm; 45 to 200 A; Al0.3Ga0.7As-In0.25Ga0.75 As; DC device performance; EHF; HEMTs; MM-wave devices; MODFETs; Matthews and Blakeslee model; RF device performance; atomic-planar; critical thickness; current gain cutoff frequency; influence of quantum well width; maximum channel current density; pseudomorphic devices; semiconductors; Bandwidth; Current density; Cutoff frequency; Distributed parameter circuits; Indium; Performance gain; Radio frequency; Sampling methods; Schottky diodes; Signal generators;
Journal_Title :
Electron Devices, IEEE Transactions on
