Nondestructive sample imaging

A system for imaging a sample, the system comprising:

• a sample holder configured to secure the sample;
• an electron beam generator configured to produce an electron beam within a vacuum chamber;
• a first spectral X-ray detector, positioned adjacent to the electron beam generator, that is configured to measure first X-rays resulting from the electron beam interacting with the sample;
• a second spectral X-ray detector, spaced apart from the electron beam generator and the first spectral X-ray detector, that is configured to measure second X-rays resulting from the electron beam interacting with a target that is positioned between the electron beam generator and the sample holder;
• and
• a processor configured to receive data generated by the first spectral X-ray detector and the second spectral X-ray detector, and further configured to perform a three-dimensional reconstruction of the sample.

A method for imaging a sample comprising:

• directing an electron beam from an electron beam generator toward the sample and a target positioned between the sample and the electron beam generator;
• acquiring first data over a first area of the sample in a first mode of operation by measuring backscattered electrons by at least two electron detectors, the backscattered electrons resulting from the electron beam interacting with the sample;
• acquiring second data over a second area of the sample in a second mode of operation by photon counting of X-rays from the target using a spectral X-ray detector;
• performing an inversion on the first data and the second data;
• acquiring one or more model priors for the sample;
• and
• generating a reconstruction of the sample using the one or more model priors and the inverted first and second data.