Growth of MonX by Reactive Laser ablation

Abstract

AbstractControl of composition and phase of a series of MoNx thin films has been accomplished by reactive pulsed laser deposition (PLD). Molybdenum foil targets were ablated in a background gas of N2/H2 (10%) at pressures ranging from 40 to 120 mTorr. the MoNx films were deposited simultaneously onto (100) MgO and fused silica substrates. the films were characterized by X-ray diffraction (XRD), temperature-dependent resistivity, and Rutherford backscattering spectroscopy (RBS). the composition, phase, and electronic transport properties were found to depend on N2/H2 pressure, substrate temperature, and substrate orientation. the highest superconducting transition temperature (Tc ) was observed in a hexagonal Mo2N film where Tc (onset) ≈ 8 K. IN general, Tc was observed to correlate most closely with the N/Mo ratio. as the ratio of N/Mo increased above optimal M02N composition, Tc decreased. Films grown on MgO generally had higher N/Mo ratios and hence lower Tc values than films deposited on silic A.