Reactively sputtered NbN Schottky contacts on GaAs and their thermal stability

The thermal stability of physical, chemical, and electrical properties of magnetron-deposited NbN thin films on GaAs were investigated. A variety of characterization methods, including Auger analysis, Rutherford backscattering spectrometry analysis, and Schottky barrier measurement showed that the NbN/GaAs interface remains stable after rapid thermal annealing at 850°C for 10 s for NbN films prepared at a 2 and 5% nitrogen content in working gas mixture. It was found that the best electrical parameters (barrier height 0.77 eV and ideality factor 1.11) of NbN/GaAs Schottky contacts were measured for the highest annealing temperature (900°C, 10 s) and the lowest nitrogen content (2%) in working gas mixture.