Installation of ion implantation beam line for 3 MV Tandem Pelletron

Abstract

An MeV energy beam line for ion implantation of carbon and silicon to fashion optically-active nanocrystals has been constructed at the Ion Beam Modification and Analysis Laboratory at the University of North Texas (UNT). The implantation line is at 15° and consists of a set of slits to define the beam, a doublet quadrupole focusing lens, a 40kV electrostatic ion beam raster scanner and target chamber for 2cm diameter circular implants. A 1.95m drift section between the scanner and target is sufficient to accommodate 10MeV carbon and silicon ions. It was determined that the separation between the slits and quadrupole should be at least 10cm to achieve point-to-parallel focusing in the beam line. It was also determined that, for a slit opening of 2mm, the distance between the upstream bending magnet and the analyzing slit should be at least 20cm to allow only single isotopes of carbon to pass into the beam line.