Performance of an amorphous silicon mini module in the initial, light-induced degraded and annealed states

This work analyses the performance of single junction amorphous silicon (a-Si) mini modules in three main states: the initial non-degraded state, degraded state after light soaking and recovered state after thermal annealing. The applied methods of controlled indoor light-soaking and thermal annealing are detailed. Performance measurements are carried out under varying spectrum (E), light intensity (G) and temperature (T). Results show a reduction in STC power of up to 27.5% during the first 250h light soaking and a recovery of 56% after annealing for 250h at 80°C in the dark. After light soaking, devices also showed a reduction in low light performance and an increase in temperature coefficients, which was partly re-versed after annealing.