Potential Induced Degradation (PID) is an effect that causes a loss of power and in severe cases even the functionality of a PV module. It occurs on many silicon photovoltaic panels when they are in the field.
Modules produced with PID-free EVA and PID-free Cells are considered PID-resistant modules.
Cell manufacturers have different ways to develop PID-free cells from the cell manufacturing perspective.
Two key factors that help make a PV Cell PID Free: i) a native oxide layer on the wafer (before depositing the silicon nitride coating),
ii) Silicon-rich, silicon nitride thin film coating on the PV cells also yields PID resistance modules.
Most cell manufacturers prefer to fabricate the cells with a native oxide layer on the wafers before depositing silicon nitride coating, commonly known as surface quality improvement.
The SiO2 layer formed in between emitter and silicon nitride prevents local shunting in solar panels and thus we get PID resistance in the PV cells.
Data & Image Credits : RenewSys