A new method is used to simulate InGaAs/InP composite channel high electron mobility transistors （HEMTs）. By coupling the hydrodynamic model and the density gradient model, the electron density distribution in the channel in different electric fields is obtained. This method is faster and more robust than traditional meth- ods and should be applicable to other types of HEMTs simulations. A detailed study of the InGaAs/InP composite channel HEMTs is presented with the help of simulations.
By epitaxial layer structure design and key fabrication process optimization,a lattice-matched InP-based In0.53Ga0.47 As-In0.52Al0.48As HEMT with an ultra high maximum oscillation frequency （fmax） of 183GHz was fab- ricated. The fmax is the highest value for HEMTs in China. Also, the devices are reported, including the device structure, the fabrication process, and the DC and RF performances.
Lattice-matched In0.5 Ga0.47 As/In0.52 Al 0.48 As high electron mobility transistors （HEMTs） with a cutoff frequency （ft） as high as 218GHz are reported. This fT is the highest value ever reported for HEMTs in China. These devices also demonstrate excellent DC characteristics：the extrinsic transconductance is 980mS/mm and the maximum current density is 870mA/mm. The material structure and all the device fabrication technology in this work were developed by our group.
