Figure 3
From: Nickel-containing nano-sized islands grown on Ge(111)-c(2 × 8) and Ag/Ge(111)-(√3 × √3) surfaces
STM images showing Ni-induced structures on Ge(111)-c(2 × 8) surface. (a) Ring-like defects in single and trimer configurations. Inset: 7 × 7 nm2 filled-state image taken at a sample bias of -0.6 V, showing ring-like defects. (b) 2√7 × 2√7 islands are enclosed by solid circles, whereas the 3 × 3 island is enclosed by a dotted circle. Insets: 12 × 10 nm2 images of the same 2√7 × 2√7 island taken at a positive (upper inset) and a negative (lower inset) bias voltage. (c) Empty-state image of a magnified 3 × 3 island. Inset: 13 × 15 nm2 filled-state image of the same island. Image size is indicated in each image. The notations in left upper corners represent the specified structures. Corresponding schematic diagrams against a background of the Ge(111)-c(2 × 8) structure are shown in right half parts.