Ion beams are an excellent tool for the study of materials and microstructures. One of these analytical techniques is based on detection and measurement of the backscattered ions’ kinetic energy. We developed a system for such measurements, suitable also for in-vacuum operation. We designed a custom printed circuit board based on a charge sensitive preamplifier. We compared the operational quality of two different semiconductor detectors: a pin-photodiode and a laboratory solar cell with a pn-structure, both with an open semiconductor structure so that α particles could reach the sensitive volume.
Measurements were performed under various physical conditions. Output voltage signal was sampled with a fast AD converter. We analysed the data in the Scilab software suite, allowing us to prepare the measured energy spectra and estimate the achieved energy resolution. We noticed differences in the output signal rise times, revealing different charge collection velocities in different types of diodes.
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