Facile Preparation of a Platinum Silicide Nanoparticle-Modified Tip Apex for Scanning Kelvin Probe Microscopy.

Chun-Ting Lin,Ming-Hua Shiao,James Su,Chien-Nan Hsiao,Chien-Ting Wu,Yu-Wei Chen,Mao-Nan Chang

doi:10.1186/s11671-015-1096-8

Abstract

In this study, we propose an ultra-facile approach to prepare a platinum silicide nanoparticle-modified tip apex (PSM tip) used for scanning Kelvin probe microscopy (SKPM). We combined a localized fluoride-assisted galvanic replacement reaction (LFAGRR) and atmospheric microwave annealing (AMA) to deposit a single platinum silicide nanoparticle with a diameter of 32 nm on the apex of a bare silicon tip of atomic force microscopy (AFM). The total process was completed in an ambient environment in less than 3 min. The improved potential resolution in the SKPM measurement was verified. Moreover, the resolution of the topography is comparable to that of a bare silicon tip. In addition, the negative charges found on the PSM tips suggest the possibility of exploring the use of current PSM tips to sense electric fields more precisely. The ultra-fast and cost-effective preparation of the PSM tips provides a new direction for the preparation of functional tips for scanning probe microscopy.

Highlights

With the prosperous development of nanotechnology, the demand on nondestructive analysis of the distribution of charge density [1], magnetic field [2], surface potential [3], etc. is surging in nanometrology
We introduced atmospheric microwave annealing (AMA) to further stabilize the tip apexes by transforming the Pt NPmodified silicon tip apexes (Pt tips) into platinum silicide NP-modified tip apexes (PSM tips)
In a typical localized fluoride-assisted galvanic replacement reaction (LFAGRR) process, we utilized a slice of commercial anodic aluminum oxide (AAO) with 100 nm of pore size (Whatman) as the template for carrying the electrolyte comprising 0.01 M chloroplatinic acid (H2PtCl6) and 16 % (v/v) buffered oxide etchant (BOE)

Summary

Introduction

With the prosperous development of nanotechnology, the demand on nondestructive analysis of the distribution of charge density [1], magnetic field [2], surface potential [3], etc. is surging in nanometrology. In the field of nondestructive analysis, scanning Kelvin probe microscopy (SKPM) has been widely used to analyze the surface potential distribution of materials [4,5,6]. The spatial resolution was seriously limited because of the stray-field generated by the metallic coating [7,8,9]. To reduce this strayfield phenomenon, many nanostructures have been proposed for tip modifications, including carbon nanotube [10,11,12], Pt nanowire [13], single metallic nanoparticle (NP) [14, 15], etc.

Methods

Results

Conclusion