ELECTROSTATIC ENERGY ANALYZER FOR MULTI-MEV HEAVY-ION BEAM PROBES

As heavy ion beam probe energies increase, the commonly used parallel-plate energy analyzer may not be practical. A cylindrical electrostatic analyzer is being tested as a possible replacement. However, a prototype 120-degrees analyzer failed to behave as prescribed by an ideal model that neglected fringing fields. A simulation of this analyzer, which used a detailed finite element evaluation for the fringe field, predicted the behavior and suggested that a better refocus is achieved at 108-degrees. Simulation of a 108-degrees analyzer is compared to experimental measurements and confirms that the numerical model correctly predicts the analyzer's operation.