Shunt-analysis of epitaxial silicon thin-film solar cells by lock-in thermography

Screen‐printed epitaxial silicon thin‐film solar cells with 13·8% efficiency

“…Similar observations have been reported elsewhere. 15 For the epi-cells on Cz as well as mc-Si substrates with POCl 3 -diffused emitter, no point-like shunts, but plane-like brighter regions are observed. It is assumed that their occurrence is related to epilayer regions with increased defect density, which are even more pronounced for the mc-Si substrate.…”

“…Extensive shunts related to in-line diffused epitaxial cells have been reported previously. 15 For further evaluation of the nature of these shunts, lock-in thermography was carried out. 16 Results of the best cells for the two different emitter diffusion types on Cz-Si substrates are shown in Figure 3 All thermograms show an accumulation of edge shunts as a result of the laser cutting for edge isolation due to laser grooves across the p-n junction.…”

Epitaxial Thin Film Crystalline Silicon Solar Cells on Low Cost Silicon Carriers

“…Characterization of the solar cells by infrared lock-in thermography revealed local shunts as shown in Figure 1.18. In some circumstances these local shunts were correlated with well defined epitaxial defects [84].…”

An approach to the measurement of shunt resistance of individual subcells in thin‐film tandem devices

“…Approaches based on laser beam-induced current measurements [9,10] and infrared thermography [11,12] have been also adopted to determine the R sh distribution over the cell.…”

“…However, this technique cannot be adopted for thin‐film P–i–N PV devices, since the currents photogenerated in the i‐layer are strongly dependent on the bias voltage , and the slope of the illuminated I–V characteristic may be more affected by the drift length of photogenerated carriers rather than by R sh ; as a consequence, the shunt resistance is to be evaluated from the reverse low voltage portion of the dark I–V curve . Approaches based on laser beam‐induced current measurements and infrared thermography have been also adopted to determine the R sh distribution over the cell.…”