Dr. U. Kreissig , FZ Rossendorf
Chlorine ions with energies of 35 MeV from the Rossendorf 5 MV tandem accelerator hit the sample at angles between 7° and 22.5° relative to the surface. Three particle identifying detection techniques were used to separate the forward scattered ions and recoils from the target with respect to their energy and atomic number or mass:
A Bragg Ionization Chamber (BIC) filled with isobutan and with an 1.2 μ m thick entrance window (Mylar) was placed at the scattering angle of 30°. It separates elements with energies ≥ 0.5 MeV/u according to their atomic number. Two parameters are measurable with the chamber: The Bragg peak height, which is proportional to the atomic number of the detected particle and the total energy of the particle. Spectrum # bnsi shows a typical BIC 2D-spectrum of a thin Boron-Nitride-layer on Silicon with some impurities of Oxygen ,Carbon and Argon.