A New Direct Electron Imaging System for Biomedical Applications

High resolution electron imaging of biological assemblies such as proteins, viruses, and cells are important for biomedical diagnosis and drug discovery. We report on the design of a new CMOS direct-detection camera system for electron imaging. The active pixel sensor array includes 512 by 550 pixels, each 5 by 5 μm in size, with a ~8 μm epitaxial layer to achieve an effective fill factor of 100%. Spatial resolution of 2.3 μm for a single incident e- has been measured. A sample image of a mouse’s muscle cell is presented.