Removing Beam Current Artifacts in Helium Ion Microscopy: A Comparison of Image Processing Techniques.
Anders J BarlowJose F PortolesNaoko SanoPeter J CumpsonPublished in: Microscopy and microanalysis : the official journal of Microscopy Society of America, Microbeam Analysis Society, Microscopical Society of Canada (2016)
The development of the helium ion microscope (HIM) enables the imaging of both hard, inorganic materials and soft, organic or biological materials. Advantages include outstanding topographical contrast, superior resolution down to <0.5 nm at high magnification, high depth of field, and no need for conductive coatings. The instrument relies on helium atom adsorption and ionization at a cryogenically cooled tip that is atomically sharp. Under ideal conditions this arrangement provides a beam of ions that is stable for days to weeks, with beam currents in the order of picoamperes. Over time, however, this stability is lost as gaseous contamination builds up in the source region, leading to adsorbed atoms of species other than helium, which ultimately results in beam current fluctuations. This manifests itself as horizontal stripe artifacts in HIM images. We investigate post-processing methods to remove these artifacts from HIM images, such as median filtering, Gaussian blurring, fast Fourier transforms, and principal component analysis. We arrive at a simple method for completely removing beam current fluctuation effects from HIM images while maintaining the full integrity of the information within the image.
Keyphrases
- deep learning
- optical coherence tomography
- convolutional neural network
- high resolution
- monte carlo
- single molecule
- magnetic resonance
- risk assessment
- quantum dots
- molecular dynamics
- magnetic resonance imaging
- high throughput
- water soluble
- gold nanoparticles
- computed tomography
- drinking water
- social media
- reduced graphene oxide
- liquid chromatography
- health risk
- fluorescence imaging
- tissue engineering