Investigation of the solar cell emitter quality by LBIC-like image techniques

The distributed properties of solar cell emitters and p–n junctions such as sheet resistance, local potential and shunt resistance were studied by original methods based on the laser scanning technique. To study the shunt resistance defects the dynamical optical reflectance thermography technique has been developed thanks to new possibilities of signal treatment and 2D scanning. The experimental factors that influence on PV LBIC-like signal are analyzed. It is shown that the information about the local potential and sheet resistance distribution is contained in the LBIC-like signal measured in the galvanostatic circuit and extracted by comparison of the signal distributions obtained under different applied voltage and laser beam parameters. The samples of the mapping of the resistive properties are presented for multicrystalline silicon solar cells without and with selective porous silicon antireflection coating.