학술논문
Asymmetrically Recessed 50-nm Gate-Length Metamorphic High Electron-Mobility Transistor With Enhanced Gain Performance
Document Type
Periodical
Author
Source
IEEE Electron Device Letters IEEE Electron Device Lett. Electron Device Letters, IEEE. 29(1):4-7 Jan, 2008
Subject
Language
ISSN
0741-3106
1558-0563
1558-0563
Abstract
We report the design, fabrication and characterization of ultrahigh gain metamorphic high electron-mobility transistors. In this letter, a high-yield 50-nm T-gate process was successfully developed and applied to epitaxial layers containing high indium mole fraction InGaAs channels grown on GaAs substrates. A unique gate recess process was adopted to significantly increase device gain by effectively suppressing output conductance and feedback capacitance. Coupled with extremely small $\hbox{10}\ \mu\hbox{m} \times \hbox{25}\ \mu\hbox{m}$ via holes on substrates thinned to 1 mil, we achieved a 13.5 dB maximum stable gain (MSG) at 110 GHz for a 30-$\mu\hbox{m}$ gate-width device. To our knowledge, this is the highest gain performance reported for microwave high electron-mobility transistor devices of similar gate periphery at this frequency, and equivalent circuit modeling indicates that this device will operate at frequencies beyond 300 GHz.