Fabrication of multi-blade crystals for hard-X-ray multi-beam imaging system

We report on the fabrication of multi-blade crystals for a hard-X-ray multi-beam imaging system by using silicon microfabrication techniques. Such a crystal consists of several single-crystalline blades, which make different angles to an incident white X-ray beam and reflect X-rays satisfying the Bragg condition in the imaging system. We fabricated two types of multi-blade crystals, one- and two-point-supported, in which blades are connected by one and two bridges to the surrounding part, respectively. The reflected beams from the blades of the two-point-supported crystal were largely distorted, while those of the one-point-supported crystal provided distortion-free reflected beams. We show that multi-angle absorption-contrast X-ray imaging can be achieved using the one-point-supported crystal with sufficient crossing precision.