Properties of MoNxOy thin films as a function of the N/O ratio

Abstract

The main purpose of this work consists on the preparation of single layered molybdenum oxynitride, MoN x O y . The films were deposited on steel substrates by dc reactive magnetron sputtering. The depositions were carried out from a pure Mo target varying the flow rate of reactive gases, which allowed tune the crystallographic structure between insulating oxides and metallic nitrides and consequently electronic, mechanical and optical properties of the material. X-ray diffraction (XRD) results revealed the occurrence of molybdenum nitride for the films with low oxygen fraction: face-centred cubic phases (γ-Mo 2 N) for low nitrogen flow rate or cubic MoN x and hexagonal phase (δ-MoN) for high nitrogen flow rate. The increase of oxygen content induces an amorphization of the nitride phases and appearance of MoO 3 phases. The increase of the oxygen fraction in the films induces also a high decrease in films hardness. Residual stresses revealed to be of compressive type, in the range of very few tenths of GPa to -2 GPa. All these results have been analysed and will be presented as a function of the deposition parameters, the chemical composition and the structure of the films.2

Synthesis of nitrided MoO2 and its application as anode materials for lithium-ion batteries

“…The d-MoN phase is a metastable state and has a higher lattice constant as a result of the nitrogen incorporation [16].…”

Cation and anion vacancies in cubic molybdenum nitride

“…MoN x layers have been deposited using a range of methods and processing parameters, leading to different compositions and phases. More specifically, reactive DC sputtering [23][24][25]28,[31][32][33][34][35][36][37][38][39] yields MoN x with x = 1.08 in the γ phase (with a small amount of possible δ phase) using 60 sccm of N 2 gas flow and 55 sccm of Ar gas flow as well as a -50 V substrate bias [31], x = 0-0.54 in the γ phase using 0-26% of N 2 process gas [33] and also from 0-0.35 in the γ phase with varying N 2 / (Ar + N 2 ) gas ratio [37]. RF sputtering [40][41][42] results in x = 0.49-0.67 in the γ phase [41], x = 0.55-0.9 in the γ phase and x = 0.9-1.02 in the δ phase [40], and x = 0.9-1.8 in the B1-MoN phase, which can be described as a cubic variant of the γ phase [42].…”

Tantalum oxynitride thin films: Mechanical properties and wear behavior dependence on growth conditions

“…Transition metal oxynitride thin films possess the main advantage of tuning the oxygen/nitrogen content, thus leading to films suited for a large number of applications. The effect of oxygen addition to transition metal nitrides on the mechanical properties has been previously reported for molybdenum compounds [10], titanium compounds [11][12][13][14] and zirconium compounds [15][16][17], among others.…”

“…Molybdenum oxynitride thin films, studied by J. Barbosa et al [10], using DC reactive magnetron sputtering, revealed a strong decrease of the hardness, from~25 GPa to values lower than 5 GPa, and of Young's modulus, from~275 GPa to~50 GPa, with the increase of oxygen content in the films. Titanium oxynitride thin films seem to exhibit a similar trend concerning the mechanical properties as a function of oxygen content.…”