MHEMT with a Power-Gain Cut-off Frequency of f_(max) = 0.63 THz on the Basis of a In_(0.42)Al_(0.58)As/In_(0.42)Ga_(0.58)As/In_(0.42)Al_(0.58)As/GaAs Nanoheterostructure

摘要

The method of molecular-beam epitaxy is used to grow a In_(0.42)Al_(0.58)As/In_(0.42)Ga_(0.58)As/In_(0.42)Al_(0.58)As nanoheterostructure with a step-graded metamorphic buffer on a GaAs substrate. The root-mean-square value of the surface roughness is 3.1 nm. A MHEMT (metamorphic high-electron-mobility transistor) with a zigzag-like gate of a length of 46 nm is fabricated on the basis of this nanoheterostructure; for this MHEMT, the cutoff frequencies for the current and power gain are f_T = 0.13 THz and f_(max) = 0.63 THz, respectively.