Cu(In,Ga)Se₂ solar cells: device stability based on chemical flexibility

The proven remarkable stability and radiation hardness of Cu(In,Ga)Se₂ (CIGS) solar cells stand in contradiction to the fact that CIGS shows both short-range and long-range instabilities. This work suggests that these instabilities may in fact be a prerequisite for CIGS's stability as they allow a degree of flexibility or smartness in accommodating externally imposed changes. Two self-healing cycles are proposed, in which copper species play an important role.