Rowan Digital Works

This page contains datasets created for NSF grant number 1644655 which runs from 5/1/16 to 8/31/20. The universities participating in the project are Rowan University, Rutgers University, and Villanova University. Datasets are embargoed for 3 years from upload date.

Title: Development of a Localized Field Emission Scanning Electron Microscope and Secondary Electron Spin Polarization Analysis System

Project Description: The Major Research Instrumentation award supports the development of a novel cost-efficient electron microscope capable of imaging the top-most layers of surfaces with high spatial resolution. The scope of this project description is to combine the fundamental concepts of two types of microscopy, thereby creating a quite compact instrument that can be integrated easily with pre-existing systems. The close proximity between the source and the object provides a means of overcoming the limitations of conventional scanning electron microscopes (SEM)s and opens the possibility to use lower primary beam energies (< 100 eV).

This project concerns the combination of scanning electron and scanning probe microscopies into a single technique “Near Field Emission Scanning Electron Microscopy” (NFESEM). In essence, NFESEM is an intermediate technique in which electrons are emitted from a needle tip via field electron emission, and then impinge on and interact with the sample. As a result, electrons are ejected from the sample surface and detected. In addition, an electron spin detector will be incorporated into the system for polarization analysis of ejected secondary electrons. We intend for the NFESEM to be coupled with a spin polarimeter, in order to perform SEM with polarization analysis (SEMPA). In ordinary SEMPA, a remote source produces unpolarized electrons: magnetic contrast results from analyzing the spin of the electrons ejected from the surface. This will enable nanometric (1 nm = 1/1,000,000,000 meters) imaging of magnetic materials; in particular low dimensional magnetic systems.

The use of low energy electrons in the analysis of materials at the nanoscale will have an influence over many areas including biological, medical, data storage, computing and renewable energy. The device will immediately provide an alternative, high resolution surface imaging device to researchers in both New Jersey and Eastern Pennsylvania.