Reactive skull melting, a method developed for this work and herein presented, combines crystal growth of zirconia-based materials and their direct nitridation in one step. The nitrogen content of nitrided YSZ single crystals strongly depends on the nitrogen solubility in the melt. Stabilization of the tetragonal or cubic phase is mainly determined by the yttria dopant concentration, the amount of incorporated nitrogen, and reduction caused by the low oxygen activity and hydrogen in the gas atmosphere. Yttria-doped zirconium oxide nitride single crystals with a maximum nitrogen content of 0.58(3) wt% and 4 mol% yttria were obtained by this method. (C) 2011 Elsevier B.V. All rights reserved.