Silicon avalanche photodiode linear-array detector with multichannel scaling system for pulsed synchrotron X-ray experiments

We developed an X-ray detector system using a 64-pixel silicon avalanche photodiode (Si-APD) linear array and fast pulse-counting electronics for multichannel scaling. The Si-APD linear array consists of 64 pixels each 100 x 200 mu m(2) in size, with a pixel pitch of 150 mu m and depletion depth of 10 mu m. The fast electronics, consisting of an ultrafast application-specific integrated circuit and field-programmable gate arrays, can record both the position and timing of X-rays arriving at each pixel of the linear array with 1 ns pulse-pair resolution. The count distribution was measured using 14.4 keV synchrotron X-rays for nuclear resonant forward scattering experiments on Fe-57, and the spatial resolution was improved by inclining the detector. We also successfully measured amorphous alloy Fe78Si9B13 during heating.