Pvi20 Front Cover indd

Figure 9. (a) Image of the front-side metal grid of a metal-wrap-through solar cell. (b) Corresponding local distribution of the 
series resistance of the solar cell under maximum power conditions, after being processed by the GRIDDLER software [10].
(a)
(b)
Figure 10. Two-diode model of a solar cell, and the corresponding mathematical 
description of the 
J-V
 characteristics of the cell.
Series resistance
70%
Shunt resistance
10%
Non-ideal
20%
Figure 11. 
FF 
loss analysis of a standard industrial p-type Al-BSF solar cell. 

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Cell 
Processing
high-precision measurements and relatively 
simple modelling. This analysis results in 
a ‘health check’ for the solar cell under test 
and clearly illustrates the most effective 
route for the manufacturer of the solar 
cell towards achieving higher efficiencies. 
The loss quantification method has been 
found to be extremely useful at SERIS 
for optimizing various types of solar cell 
design, as it enables the largest root causes 
of poor cell performance to be focused on 
first, before ‘turning knobs’ to fine-tune 
secondary effects.
Acknowledgements
The authors thank their colleagues from 
the Silicon Photovoltaics Cluster of SERIS 
for their assistance in sample processing 
and characterization. SERIS is sponsored 
by the National University of Singapore 
(NUS) and Singapore’s National Research 
Foundation (NRF) through the Singapore 
Economic Development Board (EDB). 
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