Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 2010 · 15 citations · 0 references
Natural SciencesMaterials EngineeringMaterials ScienceNanomaterialsNanotechnologyRadiation DetectionComputed TomographyComputed Tomography PhysicsElectron MicroscopyX-ray DetectionX-ray DetectorsX-ray OpticsComputer TomographyElectron Beam FocusingExposure Time ReductionPhoton DetectionQuantum EfficiencyScanning Electron MicroscopyX-ray Computed TomographyX-ray Imaging Systems
We have developed an x-ray computer tomography (CT) add-on to perform X-ray micro- and nanotomography in any scanning electron microscope (SEM). The electron beam inside the SEM is focused on a metal target to generate x-rays. Part of the X-rays pass through the object that is installed on a rotation stage. Shadow X-ray images are collected by a CCD camera with direct photon detection mounted on the external wall of the SEM specimen chamber. An extensive description on the working principles of this micro/nano-CT add-on together with some examples of CT-scans will be given in this paper. The resolution that can be obtained with this set-up and the influence of the shape of the electron beam are discussed. Furthermore, possible improvements on this SEM-CT set-up will be discussed: replacing the backilluminated CCD with a fully depleted CCD with improved quantum efficiency (QE) for higher energies, reduces the exposure time by 6 when using metal targets with x-ray characteristic lines around 10 keV.