Enhanced Focused Ion Beam Scanning Electron Microscopy (FIB-SEM)
Focused Ion Beam Scanning Electron Microscopy (FIB-SEM) is an advanced technique to make 3D images of biological cells in tissues with superior z-axis (vertical) resolution, generating easily interpretable data for reconstruction. FIB-SEM produces detailed images of cell features like protein complexes and membranes through sequential etching of a sample surface by an electron beam. Until the developments of Enhanced FIB-SEM by C. Shan Xu and Harald Hess, presented here, the image produced had been limited to a single cell or small volume of cells.
The inherent technical limitations on FIB-SEM were slow imaging speed and lack of long-term system stability, that improved on the abilities of TEM, still limited the image volume. The Hess lab masterfully re-engineered the FIB-SEM instrument orientation, reliability, and self-correction components, developed instrument designs and techniques to accelerate image acquisition and achieving dramatically improved performance.
This development continues with the full resources and attention of the FIB-SEM Technology, led by C. Shan Xu.
The enhanced FIB-SEM methods allows a system to operate continuously for months an image volumes greater than 106 µm3. At this range, connectomics studies and mapping neuronal processes is possible and it avoids tedious human proofreading.
The subject of an issued US Patent, enhanced FIB-SEM includes the following features:
In-line automatic focus, stigmation, and aperture alignment optimization
Temperature and currents monitoring
Closed-loop control of FIB milling
Email notification for warnings and auto-pause of operation to avoid sample damage
Auto restart after pause
Multiple magnifications at user selected intervals
Real-time image alignment
The high-impact developments described here, and in more detail in the publication, have made a substantial change in FIB-SEM enabled research, as shown by the 97 citations times of the first publication. The patent rights and designs are available for commercial license for manufacture and sale.
US Patent 10,600,615
European Patent Application EP3574518A2
C. Shan Xu
Kenneth Jeffrey Hayworth
Tech ID: 2014-017