We report on the fabrication of InAs-insertedchannel InAlAs/InGaAs inverted HEMTs with NbN electrodes made by using a DC magnetron sputtering deposition and we describe the device characteristics we obtained. Excellent pinchoff characteristics were obtained even at -10 K when NbN electrodes retain their superconductivity. For a 3-u,m-gate device, the maximum extrinsic transconductance at 10 K was 300 mS/mm, even at the very low drain voltage of 0.2 V. We found that the HEMTs with NbN electrodes, not only have superior characteristics at -10 K that exceed the critical temperature of Nb, but are also able to combine with NbN Josephson junctions.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Electrical and Electronic Engineering