Title :
Design of a Scanning Atom Probe with Improved Mass Resolution using Post Deceleration.
Author :
Grennan-Heaven, N. ; Cerezo, A. ; Godfrey, T.J. ; Smith, G.D.W.
Author_Institution :
Dept. of Mater., Oxford Univ.
Abstract :
Calculations and experimental results obtained using post deceleration of ions to improve the mass resolution are presented. Various extraction and counter electrode geometries, tip to extraction electrode distances and 3 different pulse shapes have been evaluated. Experimental mass resolutions of 767 FWHM and 219 FWTM have been achieved reproducibly for the 184W3+ peak without the use of a reflection lens. 3D finite element electrostatics software has been used to simulate the ion trajectories through the instrument and thus calculate the expected mass resolution for the different electrode configurations. The observed trends are found to agree well with experimental results
Keywords :
atom probe field ion microscopy; 3D finite element electrostatics software; counter electrode geometries; electrode configurations; ion trajectories; mass resolution; post deceleration; scanning atom probe; Atomic measurements; Counting circuits; Electrodes; Finite element methods; Geometry; Lenses; Probes; Pulse shaping methods; Reflection; Shape;
Conference_Titel :
Vacuum Nanoelectronics Conference, 2006 and the 2006 50th International Field Emission Symposium., IVNC/IFES 2006. Technical Digest. 19th International
Conference_Location :
Guilin
Print_ISBN :
1-4244-0401-0
DOI :
10.1109/IVNC.2006.335351
