Typical hillocks and spirals on flux-grown DyFeO3 crystal surfaces

Multi-sided and almost rectangular growth hillocks on {1 1 0} faces of flux-grown DyFeO 3 crystals are illustrated. Some such hillocks exhibit spiral growth layers originating from the summits of hillocks. Spiral growth layers originating from more than one initiation centre interact, giving rise to closed loop, interlocked and interlaced or other complex growth forma- tions. The origin of the multi-sided hillocks is attributed to preferential growth at the sites of screw dislocations in DyFeO3 crystals. Defects other than screw dislocations also stimulate growth on {1 1 0} faces of DyFeO3 crystals. An example of this is offered. The mechanism of independent growth on {1 1 0} faces of these crystals is discussed.