Carbon-backed thin tin ( 116 Sn) isotope target fabrication by physical vapor deposition technique
- PDF / 1,013,685 Bytes
- 8 Pages / 595.276 x 790.866 pts Page_size
- 104 Downloads / 163 Views
Carbon-backed thin tin (116Sn) isotope target fabrication by physical vapor deposition technique Nabendu Kumar Deb1 · Kushal Kalita1 · Pankaj Kumar Giri2 · S. R. Abhilash3 · G. R. Umapathy3 · Rohan Biswas3 · Amar Das1 · D. Kabiraj3 · S. Chopra3 · M. Bhuyan4 Received: 27 January 2020 © Akadémiai Kiadó, Budapest, Hungary 2020
Abstract In nuclear reaction experiments, the thin targets are required. In the present work, 30 thin 116Sn targets were prepared using physical vapor deposition technique (preferable for thin film fabrication) on carbon backing with usage efficiency of 98%. The carbon-backed thin target films along with the parting agents are deposited on the particular substrates using a diffusion pump based coating unit. The thicknesses of the targets were verified using α-energy loss and RBS technique and they were in good agreement with each other. The purity of the target, verified using RBS, EDS and XRD techniques, were also tested with confirmation. Keywords Physical vapor deposition · Carbon-backed 116Sn target · Rutherford backscattering spectroscopy · Energy dispersive X-ray spectroscopy · Thin film · X-ray diffractometer
Introduction The nuclear reaction requires a projectile beam and the target of very good quality with uniform and small thickness, good tensile strength, good adhesion between the thin film and the substrate, low enmesh of gas and minimum contamination [1], which makes its fabrication quite arduous. For heavy ion induced nuclear reaction studies using mass analyzer, where the reaction products are separated from the beam like particles and disperses the nuclei of interest at its focal point with good mass resolution, thin self-supporting targets (few mg/cm2 to some µg/cm2) are called for to obtain the best results [2]. This will reduce the energy loss of projectile beam and the encapsulation of reaction products within the target. This will give clear spectrum with good * Kushal Kalita [email protected] 1
Department of Physics, Gauhati University, Guwahati, Assam 781014, India
2
Department of Physics, Central University of Jharkhand, Ranchi 835205, Jharkhand, India
3
Inter University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi 110067, India
4
Department of Physics, Rangia College, Rangia, Assam 781354, India
segregation of various reaction products. In order to measure fusion excitation function precisely and to determine barrier distribution, small energy steps are necessary. And the energy lost by the incident beam must be lesser than the energy steps. To prepare such targets, thermal evaporation (one of the types of physical vapor deposition) is the most effective method [3, 4]. But due to difficulties in obtaining such thin self-supporting target foil (mostly for high Z elements), target materials are evaporated on a thin lower Z backing material, viz., carbon foil (≈ 30 µg/cm2) which will minimize the energy loss and energy straggling effects of the projectile beam. Carbon remains inert with most of the metals, thereby allowing it to be the first c
Data Loading...
