Accompanying growth and room-temperature ferromagnetism of η-Mn3N2 thin films by molecular beam epitaxy

► The films of two types of η-Mn3N2 have been grown by molecular beam epitaxy. ► Mn3N2A and Mn3N2B coexisted in the films on LaAlO3 and LaSrAlO4. ► The room-temperature ferromagnetism of the Mn3N2 films on LaAlO3 was obtained.