Journal Article

Phase Composition and Thermoelectric Properties of Epitaxial CrMoVN Thin Films

Hjort, Victor, Eklund, Per, Chowdhury, Susmita, Singh, Niraj Kumar, Shu, Rui, Le Febvrier, Arnaud

2023

Overview

Thin films of CrMoVN are deposited on c‐plane sapphire (Al2O3 (0001)) by direct current reactive magnetron sputtering, to investigate the effects of Mo and V addition to CrN‐based films. All films grow epitaxially, but Mo incorporation affects the crystal structure and nitrogen content. All films in the CrMoVN series are understoichiometric in nitrogen, but largely retain the NaCl B1 structure of stoichiometric CrN films. Addition of vanadium increases the phase‐stability range of the cubic phase, allowing for higher solubility of Mo than what has previously been reported for cubic CrN. The Seebeck coefficient and electrical resistivity are greatly affected by the alloying, showing a decrease of the Seebeck coefficient along with a decrease in resistivity. Cr0.83Mo0.11V0.06Nz shows a 70% increase in power factor (S2σ = 0.22 mW m−1 K−2) compared to the reference CrNz (S2σ = 0.13 mW m−1 K−2). Thermoelectric (TE) materials are in use in several applications, but often have too low efficiency. For more widespread use of these materials, fundamental research on TE material system is necessary. In this work, alloying in CrN, with the hope of pushing a material with great promise closer to applications, is investigated.

• Publisher: John Wiley & Sons, Inc,Wiley-VCH
• Subject: alloys / Aluminum oxide / chromium / Conductivity / CrN / Crystal growth / Crystal structure / Direct current / Electrical resistivity / Epitaxial growth / epitaxy / Heat conductivity / Investigations / Magnetic properties / Magnetron sputtering / Morphology / nitrides / Nitrogen / Phase composition / Power factor / Sapphire / Seebeck effect / Sodium chloride / Spectrum analysis / thermoelectrics / Thin films / Vanadium