High Resolution Sheet Resistance Mapping to Unveil Edge Effects in Industrial IBC Solar Cells

Quantification of pn-Junction Recombination in Interdigitated Back-Contact Crystalline Silicon Solar Cells

“…The solar cell parameters for both groups were evaluated from light J-V measurements as shown in Table 1. Note that the cell efficiencies obtained here are about ~1.8% absolute lower than the current record efficiencies for Mercury cells of 21.1% [5].…”

“…ECN's IBC concept Mercury, based on a FFE, has so far reached conversion efficiencies up to 21.1%. [4], [5] Although the problems of electrical shading thus can be minimized, in this work it will be shown that another mechanism can induce a significant loss in performance for diffused-junction IBC solar cells. Specifically, it will be shown that a distinctive charge-carrier recombination current can be associated with the presence of the pn-junctions which border the at the rear surface of the solar cell.…”

“…Note that only the test structures in the center of the wafer were used to prevent "edge effects", which showed a significant higher recombination. [5,27] It was verified by laser cutting of the individual subcells that there was no cross correlation between them. By fitting the suns-V oc measurements to a two-diode model, the J 01 , J 02 , pseudo fill factor (pFF), and shunt resistance R Shunt were extracted.…”

Industrial Applications of Terahertz Sensing: State of Play

“…TDS and FDS were both employed in reflection mode for inspection of commercial solar cells, successfully detecting manufacturing faults such as defects in tab wires and soldering, cracks, and variations in doping [124,125]. Tip-based near-field transmission measurements improved the spatial resolution of the image down to 10 μm [126,127,128,129,130,131]. The technique produced maps of sheet resistance capable of revealing faults in individual devices (Figure 19).…”

High‐Efficiency Interdigitated Back Contact Silicon Solar Cells with Front Floating Emitter

“…“Pumping effect” utilizes the voltage gradient in FFE layer to enable the holes to transport a longer distance, allowing the BSF width to be as wide as the emitter width without significant loss in cell efficiency. Up to now, ECN and Fraunhofer ISE have achieved the low‐cost FFE‐IBC solar cells with the top efficiencies of 21.1% and 22.4%, respectively . Relevant investigations have also made remarkable progress, for example, the high negative charge density of dielectric Al 2 O 3 has better passivation performance for the FFE layer, the p–n junction of the overlapping formation of the emitter and BSF diffusion zones leads to more carrier recombination, FFE‐IBC solar cells show less efficiency loss at low illumination intensity than standard p‐type H pattern cells, FFE‐IBC solar cells have higher conversion efficiency (Eff) than n‐type passivated emitter rear totally diffused (n‐PERT) cells under the same conditions …”