Single crystals of yttria-stabilized zirconia (YSZ) were irradiated with 400 keV Xe ion-beam at room temperature and -90°C. Defect growth was monitored in situ with Rutherford Backscattering and ion channeling (RBS/C) techniques using a 2 MeV He ion-beam. The irradiated YSZ was observed to consist of a 60 nm less-damaged or defect-denuded top layer, followed by a highly disordered layer. Ion channeling revealed that the degree of lattice disorder saturated at 70% of the random level in the bottom layer. At a dose of 3 10 2 0 Xe/m 2 , this layer extended to a depth of 160 nm, well beyond the irradiated depth (< 110 nm). Cross-sectional transmission electron microscopy observations along with RBS measurements are interpreted as indicating the presence of small Xe precipitates with an average diameter of 3 nm, uniformly distributed over the 20-110 nm depth. The study demonstrated that point defects generated in the Xe-irradiated region diffused and produced stable extended structural defects at depths beyond the irradiated region.