Title :
Comparisons of microwave performance between single-gate and dual-gate MODFETs
Author :
Chen, Y.K. ; Wang, G.W. ; Radulescu, D.C. ; Eastman, L.F.
Author_Institution :
Sch. of Electr. Eng., Cornell Univ., Ithaca, NY, USA
Abstract :
Both a 1.2- mu m and a 0.3- mu m gate length, n/sup +/-GaAs/InGa/n/sup +/-AlGaAs double-heterojunction MODFET have been fabricated with single-gate and dual-gate control electrodes. Extrinsic DC transconductance of 500 mS/mm has been achieved from a 0.3- mu m single-gate MODFET. The device also has a current gain cutoff frequency f/sub T/ of 43 GHz and 14-dB maximum stable gain at 26 GHz with the stability factor k as low as 0.6 from the microwave S-parameter measurements. At low-frequency dual-gate MODFETs demonstrate higher gain than the single-gate MODFETs. However, the k of dual-gate MODFETs approaches unity at a faster rate. Power gain roll-off slopes of 3-, 6-, and 12-dB/octave have been observed for the dual-gate MODFETs.<>
Keywords :
III-V semiconductors; aluminium compounds; gallium arsenide; high electron mobility transistors; indium compounds; solid-state microwave devices; 0.3 micron; 1.2 micron; 14 dB; 26 GHz; 43 GHz; 500 mS; DC transconductance; GaAs-InGaAs-AlGaAs; current gain cutoff frequency; double-heterojunction MODFET; dual-gate MODFETs; maximum stable gain; microwave S-parameter measurements; microwave performance; power gain roll-off slopes; single-gate MODFET; stability factor; Current measurement; Cutoff frequency; Electrodes; Frequency measurement; HEMTs; MODFETs; Microwave devices; Microwave measurements; Stability; Transconductance;
Journal_Title :
Electron Device Letters, IEEE