mHEMT Technology
All monolithic microwave integrated circuits (MMICs), which are required to realize the high frequency components, were manufactured using Fraunhofer IAF metamorphic high electron mobility transistor (mHEMT) technology. The mHEMT features an Indium Gallium arsenide (InGaAs) channel with high Indium content for an excellent noise characteristic similar to Indium Phosphide (InP) based HEMTs, but is grown on a conventional Gallium Arsenide (GaAs) wafer. To adapt the different lattice parameters, a metamorphic buffer layer is grown between the GaAs substrate and the active device layers. The high electron mobility in the channel and the better charge confinement, due to larger band offsets, make the mHEMT technology the most appropriate device for high frequency and ultra-low-noise applications while simultaneously being cost efficient, due to the use of GaAs wafers.