A method for microbeam spot particle distribution measurements

A method for beam particle: distribution measurements of a microprobe is pr esented. The proposed method overcomes the disadvantages of the conventiona l technique of scanning the beam over a metal edge, which is limited to one dimension and possesses statistical uncertainty, The proposed method is ba sed on scanning the beam in two dimensions over a very small aperture (pinh ole) located in the image plane and measuring the beam intensity passing th rough the pinhole as a function of the scan position. Based on the reasonab ly accurate simulation of an experiment obtained with a pinhole prototype, the simulation program was employed to propose a pinhole design with a late ral resolution sufficient to resolve the particle distribution within a bea m spot of 1 mu m in diameter. (C) 1999 Elsevier Science B.V. All rights res erved.