Enhancing the time resolution of an EBT system via the primary electron pulse shape measurement

The use of an avalanche photodiode for the direct measurement of the primary electron current pulse of an EBT system is described with reference to the low beam accelerating voltages used in MOS IC testing. Using a known signal as an input to a matched impedance microstrip line, a numerical deconvolution technique has been employed to the signal sampled by finite duration current pulses to evaluate the goodness of the restoration of the original signal. The experimental results show a good agreement of the measured pulse widths with the nominal ones for pulse duration down to 5 ns while, for shorter pulses, some deviations arise due to the different mechanism adopted for the primary electron pulse formation in the blanking unit