Pixelated transmission-mode diamond X-ray detector

Abstract

Fabrication and testing of a prototype transmission-mode pixelated diamond X-ray detector (pitch size 60–100 µm), designed to simultaneously measure the flux, position and morphology of an X-ray beam in real time, are described. The pixel density is achieved by lithographically patterning vertical stripes on the front and horizontal stripes on the back of an electronic-grade chemical vapor deposition single-crystal diamond. The bias is rotated through the back horizontal stripes and the current is read out on the front vertical stripes at a rate of ∼1 kHz, which leads to an image sampling rate of ∼30 Hz. This novel signal readout scheme was tested at beamline X28C at the National Synchrotron Light Source (white beam, 5–15 keV) and at beamline G3 at the Cornell High Energy Synchrotron Source (monochromatic beam, 11.3 keV) with incident beam flux ranges from 1.8 × 10−2to 90 W mm−2. Test results show that the novel detector provides precise beam position (positional noise within 1%) and morphology information (error within 2%), with an additional software-controlled single channel mode providing accurate flux measurement (fluctuation within 1%).