Composition, structure, and semiconducting properties of Mg _x Zr_2−x N₂ thin films

Abstract

Synthesis and characterization of Mg x Zr 2−x N 2 (0.5 ⩽ x ⩽ 1.8) thin films deposited by reactive magnetron co-sputtering in nitrogen plasma is reported. Composition measurements show that nitrides with low oxygen content (less than 1%) can be formed up to x = 1.0, at which point an increase in oxygen content is observed. Up to composition of x = 1.6 the Mg x Zr 2−x N 2 thin films form in a rocksalt-derived crystal structure, as revealed by X-ray diffraction measurements. At x > 1.6 the films rapidly oxidize. The lattice constant of the stoichiometric MgZrN 2 composition is a = 4.537 Å, and only small changes in lattice parameter are observed with changing composition. Electrical conductivity decreases by several orders of magnitude with increasing Mg-content. The conductivity of Mg-rich (x ⩾ 1) films increases with increasing measurement temperature, indicating semiconducting character of Mg-rich Mg x Zr 2−x N 2 . Optical absorption measurements of these Mg-rich samples show a clear absorption onset at 1.8 eV, also indicative of semiconducting behavior.

Thin Film Synthesis of Semiconductors in the Mg–Sb–N Materials System

“…Throughout the capped films, the maximum oxygen content was around 5 at. % of the anion content in the film, which is comparable to other sputtered nitrides that contain oxophylic elements like Mg[38] [39].…”

Zn2SbN3: growth and characterization of a metastable photoactive semiconductor

“…for Mg-based nitrides such as MgZrN2, for which mobility was improved by more than an order of magnitude using the templating effect of epitaxial substrates 30,31 . Similar epitaxial methods or alternative growth techniques can be envisioned to reduce the defect density and improve the electron mobility in Zn2SbN3.…”

Phase Transformation and Superstructure Formation in (Ti0.5, Mg0.5)N Thin Films through High-Temperature Annealing

“…These compounds were all predicted to be thermodynamically stable, suggesting that they can be synthesized by physical vapor deposition. Synthesis of Mg x Zr 2−x N 2 by Bauers et al [32] confirms semiconducting properties through temperature-activated conductivity measurements and an onset in the optical absorption spectrum.…”