Abstract

Recent developments in position sensitive detectors pave a way towards the efficient realization of Rutherford Backscattering Spectrometry/Channeling experiments in blocking geometry. Here we report on the use of a Timepix position sensitive detector (PSD) for this kind of studies. The blocking geometry in combination with a PSD brings the advantage that it is straightforward to measure full two-dimensional blocking patterns, which reveal considerably more details than one-dimensional angular scans. The Timepix detector response was first calibrated using internal test-pulses, followed by determining the energy resolution for similar to 5.5 MeV a particles from radioactive sources, and for 1.8 MeV alphas from a 2 MeV He-4(+) beam backscattered from a Au target. An effective count-rate of approximate to 2000 events/s and energy resolution of approximate to 47 keV at 1.8 MeV were achieved. Blocking effects from backscattered alpha particles were measured around the < 100 > axis of Si and the < 0001 > axis of 6H-SiC single crystals and compared to theoretical patterns calculated by means of FLUX Monte Carlo simulations, from which the angular resolution achieved with the setup could be determined to be 0.10 degrees-0.12 degrees.