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Niobium titanium nitride (NbTiN) thin films were deposited on a selection of different substrates to explore the optimum depositing condition of high-quality NbTiN thin films. The NbTiN films deposited on MgO, Al2O3, and fused quartz substrates showed excellent superconducting properties with a high TC of 14.7 K, 14.5 K, 15.2 K, and low resistivity ρ20 K of 55 μΩcm, 116 μΩcm, 78 μΩcm, respectively. The chemical composition, crystal structure, and relationship between superconducting properties and crystal structure were systematically investigated by changing the N2/(Ar+N2) ratio in sputtering gases. The lattice parameter systematically changed as N2/(Ar+N2) ratio was varied. We found that the superconducting properties depend on the lattice parameter, and the film with the best superconducting properties had a lattice parameter of 4.380 Å (on MgO), 4.345 Å (on Al2O3), 4.335 Å (on fused quartz).