Thin films of the superconducting compound NbN were deposited at atmospheric pressure on fused quartz substrates using the chemical reaction of the gaseous niobium pentachloride with ammonia & hydrogen gases in a quartz apparatus.
NbN films prepared by this method had a wide range of resistivities, temperature coefficients of resistance and superconducting transition temperatures depending on the deposition conditions. The maximum transition temperature obtained was 15.75°K for the films deposited at 900°C.
The deposition rate varied with the reaction conditions from 20 to 1, 500Å/sec, and deposits ranged from smooth films to polycrystals in which the individual crystal faces were 20 microns in length.
The X-ray diffraction data for the niobium nitride films deposited at 900°C and 1, 000°C revealed face-centered cubic structure with cube edges of about 4.334Å and 4.358Å, respectively.
