A robust tip-less positioning device for near-field investigations: Press and Roll Scan (PROscan)

TL;DR

This paper introduces PROscan, a tip-less, mechanically stable device for near-field positioning that improves nanoscopic feature placement and stability over traditional scanning probe microscopes.

Contribution

The paper presents a novel tip-less device based on substrate bulging and rolling, offering enhanced mechanical stability and nanometer precision for near-field investigations.

Findings

Achieved nanometer precision in positioning nanoparticles and quantum dots.

Demonstrated passive mechanical stability over more than one hour.

Enhanced fluorescence intensity and emission rate through precise positioning.

Abstract

Scanning probe microscopes scan and manipulate a sharp tip in the immediate vicinity of a sample surface. The limited bandwidth of the feedback mechanism used for stabilizing the separation between the tip and the sample makes the fragile nanoscopic tip very susceptible to mechanical instabilities. We propose, demonstrate and characterize a new alternative device based on bulging a thin substrate against a second substrate and rolling them with respect each other. We showcase the power of this method by placing gold nanoparticles and semiconductor quantum dots on the two opposite substrates and positioning them with nanometer precision to enhance the fluorescence intensity and emission rate. We exhibit the passive mechanical stability of the system over more than one hour. The design concept presented in this work holds promise in a variety of other contexts, where nanoscopic features have to be positioned and kept near contact with each other.