Novel Evolution Process of Zn-Induced Nanoclusters on Si(111)-(7×7) Surface

Abstract

A tiny number of Zn atoms were deposited on Si (111)- (797) surface to study the evolution process of Zninduced nanoclusters. After the deposition, three types (type I, II, and III) of Zn-induced nanoclusters were observed to occupy preferably in the faulted half-unit cells. These Zn-induced nanoclusters are found to be related to one, two, and three displaced Si edge adatoms, and simultaneously cause the depression of one, two, and three closest Si edge adatoms in the neighboring unfaulted half-unit cells at negative voltages, respectively. First-principles adsorption energy calculations show that the observed type I, II, and III nanoclusters can reasonably be assigned as the Zn 3 Si 1 , Zn 5 Si 2 , and Zn 7 Si 3 clusters, respectively. And Zn 3 Si 1 , Zn 5 Si 2 , and Zn 7 Si 3 clusters are, respectively, the most stable structures in cases of one, two, and three displaced Si edge adatoms. Based on the above energy-preferred models, the simulated bias-dependent STM images are all well consistent with the experimental observations. Therefore, the most stable Zn 7 Si 3 nanoclusters adsorbed on the Si(111)-(797) surface should grow up on the base of Zn 3 Si 1 and Zn 5 Si 2 clusters. A novel evolution process from Zn 3 Si 1 to Zn 5 Si 2 , and finally to Zn 7 Si 3 nanocluster is unveiled.

Doping behaviors of adatoms adsorbed on phosphorene

“…A Monkhorst–Pack k ‐point mesh of 11 × 11 × 1 was used to calculate the Brillouin zone integration. Structural optimizations were carried out by relaxing all the atomic geometries using the conjugate gradient algorithm . The forces on all the atoms converged to within 0.01 eV Å −1 .…”