Precursory stage of damage production in argon irradiated cubic zirconia

The damage accumulation in stabilized cubic ZrO2 single crystals irradiated with low-energy Ar ions was investigated, combining Rutherford backscatter ing/channeling (RBS/C) and slow positron implantation (SPIS) spectroscopies . In the 3 x 10(14)-10(16) cm(-2) range, the fluence dependence of the dama ge-induced dechanneling parameter (f(D)) exhibits three production stages ( labeled 1, 2 and 3) already reported for ion-irradiated ceramics and attrib uted to the formation of small clusters and dislocation loops, either isola ted or overlapping. Moreover, a precursory stage, never hitherto reported i n RBS/C studies, is unveiled for fluences below 3 x 10(14) cm(-2). This "ne w" stage (labeled 0) is confirmed by SPIS and attributed to clustering of s mall vacancy-type defects. Although both techniques exhibit different speci fic sensitivities to defects, similarities in the fluence dependence allow to identify common limits to all observed damage production stages. (C) 200 1 Elsevier Science B.V. All rights reserved.