Using the Medipix3 detector for direct electron imaging in the range 60keV to 200keV in electron microscopy

摘要

Hybrid pixel sensor technology such as the Medipix3 represents a unique toolfor electron imaging. We have investigated its performance as a direct imagingdetector using a Transmission Electron Microscope (TEM) which incorporated aMedipix3 detector with a 300 micrometre thick silicon layer compromising of256x256 pixels at 55 micrometre pixel pitch. We present results taken with theMedipix3 in Single Pixel Mode (SPM) with electron beam energies in the range,60 to 200 keV. Measurements of the Modulation Transfer Function (MTF) and theDetective Quantum Efficiency (DQE) were investigated. At a given beam energy,the MTF data was acquired by deploying the established knife edge technique.Similarly, the experimental data required to DQE was obtained by acquiring astack of images of a focused beam and of free space (flatfield) to determinethe Noise Power Spectrum (NPS).