Quantitative measurements of energy contamination in ULE2 deceleration

Deceleration is used in several new implanters to produce large fluxes of low energy ions, but charge exchange in the beamlines produces energy contamination. We have found that several issues must be addressed to obtain confident estimates of the energy contamination. Pre-amorphized wafers are used to eliminate channeling effects. A least squares fitting method is described that uses multiple drift mode reference profiles accommodate SIMS artifacts and variability. The limitations and accuracy of the method will be discussed.