Large-Area, Low-Cost, High-Resolution X-ray Detector and Electron Amplifier

This Phase I Small Business Innovation Research proposal will develop porous dielectrics as a low-cost, large-area detector for high spatial resolution x-ray detection. An alternative to microchannel plates, porous dielectric electron amplifiers are formed by a thin layer, generally less than 1 mm, of a low density dielectric. The microscopic pores formed in such material, provide a natural, but miniaturized, dynode chain for electron amplification when an electric field is applied. An x-ray photon striking the material sets off an avalanche of electrons, creating 100,000 or more electrons per incident photon. However, the small size of the pores along with a preference for propagation in the direction of the electric field result in a limited spread of output electrons from the location of the incident photon. By coupling the porous dielectric to a high resolution anode, we will be able to achieve spatial resolutions of 30 microns or better. Porous dielectrics are easily deposited, which allows the construction of detectors with areas exceeding 100 cm2, at a fraction of the cost of microchannel plates. Phase I work will produce a laboratory area imager to demonstrate the technology, while Phase II will produce commercial prototype x-ray cameras and electron amplifiers.