Abstract. This Thesis describes the development and experimental testing of a new type of single-crystal chemical vapour deposition (CVD) diamond diagnostic instrument for synchrotron X-ray radiation. This pixelated detector is capable of non-destructively imaging the X-ray beam, and can remain in the beam path for the duration of synchrotron experiments. The detector can measure the position, profile, and flux of an incident beam. It has applications in beam position and profile monitoring, enabling active beam feedback and stabilisation.

The instrument utilises a single-crystal CVD diamond plate as the detector material, with laser-written conductive graphitic tracks embedded within the bulk diamond used as electrodes. The resulting instrument is an all-carbon X-ray imaging detector. Within the instrument's transmissive aperture there is no surface metallization that could absorb X-rays, and no surface structures that could be damaged by exposure to synchrotron X-ray beams. The all-carbon design ensures that there is no danger of electrode materials introducing new absorption edges that may affect synchrotron experiments.

A novel modulation lock-in readout scheme enables each pixel of the detector to be read out simultaneously. X-rays passing through the detector generate charge carriers within the bulk diamond through photoionisation, and these charge carriers travel to the nearest readout electrode under the influence of the modulated electrical bias. The signals from individual pixels are acquired by applying different modulation frequencies to different `bias' electrodes, and measuring the resulting signal amplitude of those frequencies on perpendicular `readout' electrodes. The system is designed to provide 100 frames per second image acquisition.

This instrument overcomes many of the issues associated with current generation synchrotron diagnostic instruments, enabling real-time and non-destructive X-ray beam profile measurements to be obtained.