University of Limerick
Adegoke_2024_Real.pdf (9.69 MB)

Real-time TEM observation of the role of defects on nickel silicide propagation in silicon nanowires

Download (9.69 MB)
journal contribution
posted on 2024-03-25, 12:38 authored by Esther AdegokeEsther Adegoke, Raman Bekarevich, HUGH GEANEYHUGH GEANEY, Sergey Belochapkine, URSEL BANGERTURSEL BANGERT, KEVIN M. RYANKEVIN M. RYAN

Metal silicides have received significant attention due to their high process compatibility, low resistivity, and structural stability. In nanowire (NW) form, they have been widely prepared using metal diffusion into preformed Si NWs, enabling compositionally controlled high-quality metal silicide nanostructures. However, unlocking the full potential of metal silicide NWs for next-generation nanodevices requires an increased level of mechanistic understanding of this diffusion-driven transformation. Herein, using in situ transmission electron microscopy (TEM), we investigated the defect-controlled silicide formation dynamics in one-dimensional NWs. A solution-based synthetic route was developed to form Si NWs anchored to Ni NW stems as an optimal platform for in situ TEM studies of metal silicide formation. Multiple in situ annealing experiments led to Ni diffusion from the Ni NW stem into the Si NW, forming a nickel silicide. We observed the dynamics of Ni propagation in straight and kinked Si NWs, with some regions of the NWs acting as Ni sinks. In NWs with high defect distribution, we obtained direct evidence of nonuniform Ni diffusion and silicide retardation. The findings of this study provide insights into metal diffusion and silicide formation in complex NW structures, which are crucial from fundamental and application perspectives.



ACS Nano


American Chemical Society

Also affiliated with

  • Bernal Institute

Sustainable development goals

  • (9) Industry, Innovation and Infrastructure

Department or School

  • Chemical Sciences
  • Physics

Usage metrics

    University of Limerick


    Ref. manager