USING A CHARGE-COUPLED DEVICE (CCD) TO GATHER X-RAY FLUORESCENCE (XRF) AND X-RAY DIFFRACTION (XRD) INFORMATION SIMULTANEOUSLY, A. Reyes, H.K. Pew, P. Moody, L.V. Knight, S. Cornaby, T. Hughes, A. Stradling, pp. 343-348

A breadboard setup constructed at MOXTEK, Inc. is capable of capturing both XRF and XRD information using a charge-coupled device (CCD) as the x-ray detector. This preliminary setup will lead to a prototype simultaneous XRD/XRF instrument. NASA is funding the instrument’s construction because of its capabilities and small size; it could be used for future Mars missions for rock analysis. The instrument uses a CCD to capture both the energy information of an incoming x-ray and the position where the x-ray hit. A powdered sample of material is placed in front of the CCD and then a collimated x-ray beam bombards the sample. The energy information is used to accumulate the x-ray events caused by diffraction, thus enabling us to construct x-ray diffraction patterns. We are also able to discard split events and use all the single x-ray events to create an x-ray fluorescence spectrum from the data. The focus of this paper is how a front-sideilluminated (FSI) CCD and back-side-illuminated (BSI) CCD gather information and how this information is sorted. A split event comparison is made between the two types of CCDs.