Dr Marie Ruat, a post-doctoral fellow at Monash Centre for Synchrotron Science (MCSS), is an expert in modelling the performance of Cadmium Telluride (CdTe) and Cadmium Zinc Telluride (CZT) detector semiconductor materials.

Marie previously worked at the CEA-LETI institute (the Electronics and Information Technology Laboratory of the French Atomic Energy Commission) in Grenoble, France and at the National Microelectronics Center (Centro Nacional de Microelectrónica [CNM]) in Barcelona, Spain investigating Silicon, Cadmium Telluride  and Gallium Arsenide (GaAs) 3D detectors for medical imaging; and for the inner detector of ATLAS, one of the experiments of the Large Hadron Collider (LHC) at CERN, Geneva, Switzerland.

“Working at MCSS on the CRCBID project offered a chance to gain further experience in the experimental measurement of semiconductor detector performance, which would complement theoretical methods that I had developed in previous studies,” says Marie.

To date, Marie has developed a three dimensional model for the CRCBID Hybrid Pixel Detector, from X-ray source to pixel output. This model combines GEANT4 and COMSOL Finite Elements Method simulations, for differently configured CdTe detectors. The model can be extended to any detection material and/or pixel geometry.

She has also been closely involved with synchrotron measurements conducted by the MCSS team, under the direction of Andy Berry.   These measurements have been used to measure the performance of CdTe detectors supplied by Acrorad, using the intense high energy   monochromatic X-ray beams of the X-ray Absorption beam line at the Australian Synchrotron.

A collaborative program with the ANSTO detector group, headed by Dr Mark Reinhard, is also underway.  This program is using electrical measurements for material characterisation and focused ion beam experiments to characterise detector performance, complementing X-ray measurements.

The theory and experimental work have so far shown the expected characteristic pulse shapes in the pixel output of CRCBID’s hybrid pixel detector.

“We’ve also been investigating the charge-sharing effect in small pixel detectors, and solutions to pulse pileup, which affects the general performance of the detector,” says Andy Berry, from MCSS.  “We’re using this data to guide the design of the application specific integrated circuit (ASIC) that is the key enabling technology of CRCBID’s hybrid pixel detector.”