Thin-film Silicon Solar Cell and Module Analysis by Electroluminescence

Electroluminescence is a fast and reliable method for defect characterization of thin-film silicon large area modules. At forward bias, the injected carriers recombine via defect states in the p-i-n structure but only the radiating portion is detected by a means of a detector array. For these investigations, it is mainly assumed that the EL-signal is proportional to the local current density (J). We will present a detailed analysis of thin-film silicon modules and the circumstances will be discussed under which the simple approach with the EL-signal proportional to the current density is not valid.