High current electrostatic deflector and scanner

A high current electrostatic scanner-deflector has been designed. The scanner includes electron gates to confine the space-charge-unneutralized region to the immediate vicinity of the scanner. The remaining beam divergence due to space charge has been compensated for by the inherent focusing property of the scanner. Since this latter effect depends on the scanner length, a design may be created for a wide range of perveances. Such a scanner was successfully tested for a 2 mA, 40kV, 75As+ ion beam. This demonstrates the capability of scanning ion beam more than 10 times as intense as those normally scanned. (Auth.)