A STUDY ON THE INFLUENCE OF THE SPATIAL-DISTRIBUTION OF METASTABLE DEFECTS ON THE PROPERTIES OF A-SI-H P-I-N AND N-I-P SOLAR-CELLS - EXPERIMENT AND NUMERICAL-SIMULATION

The keV-electron irradiation technique is used to study the influence of different spatial distributions of metastable defects on the proper ties of a-Si:H p-i-n and n-i-p solar cells. The energy dependence of t he penetration depth of the keV-electrons is utilized to introduce met astable defects in different regions of the solar cells. A strong infl uence of the induced defect profiles on the open-circuit voltage and t he short-circuit current of the solar cells is found. Internal collect ion efficiency measurements and modelling show that the relative alter ation of the cell parameters contains information about the spatial di stribution of the induced metastable defects in the case of standard p -i-n and n-i-p a-Si:H solar cells. On the basis of this result it is c oncluded that bulk rather than interface degradation is the dominant e ffect after light soaking and current injection for the solar cells in vestigated in this study.