  Antiferromagnetic materials are of great interest for spintronics. Here we
present a comprehensive study of the growth, structural characterization, and
resulting magnetic properties of thin films of the non-collinear
antiferromagnet Mn$_{3}$Ir. Using epitaxial engineering on MgO (001) and
Al$_{2}$O$_{3}$ (0001) single crystal substrates, we control the growth of
cubic ${\gamma}$-Mn$_{3}$Ir in both (001) and (111) crystal orientations, and
discuss the optimization of growth conditions to achieve high-quality crystal
structures with low surface roughness. Exchange bias is studied in bilayers,
with exchange bias fields as large as -29 mT (equivalent to a unidirectional
anisotropy constant of 11.5 nJ cm$^{-2}$) measured in Mn$_{3}$Ir (111) /
permalloy heterostructures at room temperature. In addition, a distinct
dependence of blocking temperature on in-plane crystallographic direction in
Mn$_{3}$Ir (001) / Py bilayers is observed. These findings are discussed in the
context of chiral antiferromagnetic domain structures, and will inform progress
towards topological antiferromagnetic spintronic devices.
