Transition from silicene monolayer to thin Si films on Ag(111): comparison between experimental data and Monte Carlo simulation.

Alberto Curcella,Geoffroy Prévot,Yves Borensztein,Silvia Pandolfi,Romain Bernard

doi:10.3762/bjnano.9.7

Abstract

Scanning tunneling microscopy (STM), Auger electron spectroscopy (AES) and low energy electron diffraction have been used to follow the growth of Si films on Ag(111) at various temperatures. Using a simple growth model, we have simulated the distribution of film thickness as a function of coverage during evaporation, for the different temperatures. In the temperature regime where multilayer silicene has been claimed to form (470–500 K), a good agreement is found with AES intensity variations and STM measurements within a Ag surfactant mediated growth, whereas a model with multilayer silicene growth fails to reproduce the AES measurements.

Highlights

Since their discovery in 2012 [1], silicene layers have been attracting a great interest, due to the expectation of electronic properties similar to the ones of graphene, based on theoretical studies [2]
In the temperature regime where multilayer silicene has been claimed to form (470–500 K), a good agreement is found with Auger electron spectroscopy (AES) intensity variations and Scanning tunneling microscopy (STM) measurements within a Ag surfactant mediated growth, whereas a model with multilayer silicene growth fails to reproduce the AES measurements
The coverage θ has been calibrated from the breaks observed in the evolution of ISi that were attributed to the completion of a silicene monolayer

Summary

Introduction

Since their discovery in 2012 [1], silicene layers have been attracting a great interest, due to the expectation of electronic properties similar to the ones of graphene, based on theoretical studies [2]. Because of their easy synthesis, Si/Ag(111) monolayers have been intensively studied [3,4,5,6]. A buckling of 0.77 Å has been precisely measured for the (4 × 4) structure [8,9,10]. Silicene growth has been reported on other substrates, such as Ir [11], ZrB2 [12], or MoS2 [13], the precise crystallographic structure of these layers has not been elucidated yet

Methods

Results

Conclusion