Low Z Thin Film Stripper Foils, Targets and X-Ray Windows

The latest rare isotope and ion beam accelerator facilities used for important nuclear physics experiments require free standing thin film stripper foils, targets and x-ray windows made from low atomic number (low Z) elements such as Be, B and C. It is expected that the currently used thin films will need to be significantly improved due to the much higher beam power densities in the next generation nuclear research facilities including the Facility for Rare Isotope Beams (FRIB). The goal of this project is to develop technologies for the production of low Z thin films in the range from a few ug/cm2 to over 100mg/cm2 for these applications. In 2006, UHV demonstrated the feasibility of an innovative pulse laser deposition (PLD) technology to produce 2-4 layer diamond like carbon stripper foils in the 200-1,000 ug/cm2 thickness range, which are being supplied commercially for nuclear experiments and manufacture of radiopharmaceuticals throughout the world. However, recent tests at FRIB have shown quick deterioration of DLC foils under heavy ion bombardment due to thermal and mechanical stresses and radiation damage. In this Phase I project, we propose to develop SUPER nano-layered thin films by increasing the number of stress controlled low Z nano-layers in the range from a few ug/cm2 to over 100mg/cm2 for applications as charge strippers and targets in heavy ion accelerators as well as x-ray windows for gaseous detectors. The work plan includes the following objectives: (i) fabricate multi-layer thin films with Low Z nano-layers (C, 12C, 13C, Be, B) of varying thicknesses using PLD, CVD and PVD, (ii) test thin films at Cardinal Health (H- ion beam) and MSU (heavy ion beam) to study the failure mechanisms and develop methods to improve lifetime, and (iii) fabricate and provide samples of low-Z targets and x-ray windows to MSU (and others) for evaluation. To achieve success in this project, UHV has assembled a team of experts with extensive experience in nuclear accelerators, thin film fabrication and analysis, thin film equipment manufacturing, and high energy ion beam testing. These improved thin films will have very significant impact on the operating conditions of the next generation nuclear accelerator facilities, that are used not only for scientific research but also for medical and commercial isotope manufacturing. As an example, the radio-pharmaceuticals manufactured in these facilities are used to treat (radiation therapy) millions of people with cancer around the world. These nano-layered thin films will be immediately added to UHV & apos;s product line to make them commercially available through existing sales channels (www.nanoRANCH.com and www.nanoXRF.com).