In-situ AFM-SEM-EDS nanoparticle imaging and characterization

K. Arat, F. Dong, W.K. Neils, S. Spagna
Quantum Design,
United States

Keywords: AFM, EDS, SEM, correlated microscopy

Summary:

Nanoparticles (NPs) have broad applications in biological, medical, and pharmaceutical sciences, such as bio-separation, biosensing, diagnostics, and drug delivery. Because the functionality of NPs is highly dependent on their sizes, shape, surface, and material, the accurate characterization of particles is essential to their specific applications. In this work, we studied the feasibility of NPs characterization by FusionScope, a novel correlative microscope platform that seamless combines a wide range of Atomic Force Microscope (AFM) measurement techniques with the benefits of Scanning Electron Microscopy (SEM) imaging. The FusionScope integrates a SEM with a Thermal Field Emission (TFE) Schottky source, with a vacuum compatible AFM employing self-sensing cantilever technology . The system sample chamber is equipped with a trunnion allows the sample stage and the AFM scanner to rotate up to 80 degrees, providing for a unique view of AFM tip for inspection purposes. In addition, this correlative microscope has been upgraded with a state-of-the-art Energy Dispersive x-ray Spectrometer (EDS) based on Silicon Drift Detector (SDD) technology. The energy resolution of this detector is < 133 eV with a peak-to-background ratio of > 15,000. In this paper SEM-AFM-EDS correlated images of carboxyl (COOH) group functionalized magnetic NPs are presented as a model system to demonstrate the FusionScope capability.