Environmental Engineering Reference
In-Depth Information
typedopants(accordingtothep-njunctionmodel)willimprovethe
electrical conductivity of the device structure to enhance both the
shortcircuitcurrentdensityandthefillfactorand,hence,enablethe
achievement of high e
ciencies. In addition, this model would also
explain the 'magic step' of the empirical CdCl
2
treatment necessary
for achieving high e
ciencies. According to this new model,
halogens act as n-type dopants to both n-CdS and n-CdTe materials,
reducingtheseriesresistanceinadditiontoobservedgraingrowths
to enhance device parameters. The improved understanding of
material issues and physics behind this device will enable the PV
community to further develop this device rapidly in the future.
The CdS/CdTe solar cell e
ciency has stagnated at
∼
16% for
more than two decades. With the improved understanding of the
materialissuesanddevicephysics,togetherwithrightexperimental
approaches, the e
ciency of this device could exceed 20% in the
near future.
References
1. http://solar.calfinder.com/blog/solar-research/cigs-solar-record-
e
ciency/
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S.Asher,D.H.Levi,andP.Sheldon(22-26October2001)17thEuropean
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