Argon ion beam and electron beam-induced damage in Cu(In,Ga)Se2 thin films

Ar ion beam and electron beam-induced damages in Cu(In,Ga)Se2 thin films are investigated by transmission electron microscopy and X-ray energy-dispersive spectroscopy. We find that a high-energy Ar ion beam can cause severe damage in Cu(In,Ga)Se2 surface regions by preferentially depleting Se and In. The depletion can occur with an Ar ion beam at energy as low as 0.5 keV. High-energy electron beams also cause damage in Cu(In,Ga)Se2 thin films by preferentially depleting In and Ga. Our results imply that special care must be taken for measurements involving surface treatments using high-energy Ar ion beams or electron beams.