Techniques for minimizing space proton damage in scientific charge coupled devices

The authors describe proton irradiation tests and theoretical prediction programmes, mounted as part of the European Space Agency's TRP project, to show the way in which damage in EEV scientific CCDs increases with time in space. The tests give hope that certain modifications of the chip, present in some of the samples tested, can alleviate the damage considerably. Radiation damage levels required with the passage of time in the XMM X-ray astronomy mission can now be stated. With fair confidence, one can now outline engineering measures to harden the system to minimize the space damage. >