The concept of sacrificial charge and its influence on CTI will be familiar to the reader. The techniques described here artificially place charge at predetermined locations in order to influence radiation damaged devices. Charge injected via the output node. The later most is by the far the most wonderful to use but is only convenient for Astro-e sequencer users. The first 2 methods occur togther in varying degrees due to the necessary clocking operations on the one hand and the unavoidable presence of cosmic rays on the other.
Natural charge is collected in the image and frame store immediately after a readout.
This charge is swept into the serial register which is held with all phases high to allow even distribution of charge. Here is what the readout looks like. This ccid-17 has been damaged with 40 MeV protons. In general there is more than enough charge available from cosmic rays to generate a line of nearly full wells. An extra integration time of 2 seconds is about right but the actual time needs to be tuned for the background level.