Author: Gobbo, A.
Paper Title Page
Sub-Micrometer Resolution, Nanotechnology Based Wire Scanners for Beam Profile Measurements at SwissFEL  
  • S. Borrelli, M. Bednarzik, Ch. David, E. Ferrari, A. Gobbo, V. Guzenko, N. Hiller, R. Ischebeck, G.L. Orlandi, C. Ozkan Loch, B. Rippstein, V. Schlott
    PSI, Villigen PSI, Switzerland
  SwissFEL Wire scanners (WSCs) measure electron beam transverse profile and emittance with high-resolution in a minimally-invasive way. They consist of a wire fork equipped with two 5 micrometer W wires, for high-resolution measurements, and two 12.5 micrometer Al(99):Si(1) wires, to measure the beam profile during FEL operation. Although the SwissFEL WSCs resolution is sufficient for many purposes, for some machine operations and experimental applications it is necessary to improve it under micrometer scale. The WSC spatial resolution is limited by the wire width which is constrained to few micrometers by the conventional manufacturing technique of stretching a metallic wire onto a wire-fork. In this work, we propose to overcome this limitation using the nanofabrication of sub-micrometer metallic stripes on a membrane by means of e-beam lithography. This presentation focuses in the design, construction and characterization of a high-resolution WSC prototype consisting of a silicon nitride membrane onto which two gold or nickel wires, widths ranging from 2 micrometers to 0.4 micrometers, are electroplated. We will also present the preliminary electron beam tests of our prototype.