X-ray microprobe-microscopy

X-rays have a unqiue interaction with matter that offers many advantages over electrons and other charged particles for the microcharacterization of materials. X-rays are more efficient in photoejecting inner shell electrons resulting in characteristic x-ray fluorescence. X-rays also result in less Bremsstrahlung to produce higher fluorescent signal-to-background ratios than obtained with electrons. Detectable limits for x-ray produced fluorescence could be a few parts per billion which are 10-3 to 10-5 lower than for electron excitation. Energy deposition in the sample from x-rays is 10-3 to 10-4 less than for electrons for the same detectable limit. High-brightness storage rings, such as the planned Advanced Photon Source in the 7 GeV class with undulators, will have sources as brilliant as the most advanced electron probes