A clearer road ahead

Module Manufacturing
Innovation Award
SJ3 Cell
MANY multi-junction solar cell technologies are lattice
mismatched and therefore have defects within the cell.
Additional material is used to try and buffer the defects which
results in stunted efficiency gains and reliability issues.
Solar Junction's technology is lattice matched resulting in higher
performance yield reliability and lower cost.
Solar Junction has successfully produced III-V multi-junction
solar cells using dilute nitrides reaching high-efficiencies. The
material substrates used by the company allows for a tunable
and lattice-matched structure that has not been obtained by
others.
Solar Junction's cells incorporate the
company's proprietary adjustable
spectrum lattice-matched A-SLAM
technology which enables the
company to more optimally partition
the solar spectrum. This enables
bandgap tunability over the solar
spectrum to maximize the absorbed
sunlight within the CPV modules while
enabling lattice-matched pathway to
solar cell efficiencies beyond 50% within
the decade. This technology leads to
maximum efficiency and greater reliability. It is a
sustainable technology that leads to a roadmap of
continual efficiency gains and innovation without changing the
fundamental structure of the cell which is not true for other multijunction
solar cell providers.
Solar Junction breaks with multi-junction innovations by
continuing on a lattice-matched path leading to higher
efficiencies and higher reliability. The cell structure maintains
pure while other companies are using innovations that use
different processes that do not maintain a lattice-matched
structure. Solar Junction standard cell achieved 40.9% efficiency
in January 2011 which was tested and verified by the National
Energy Laboratory (NREL.)
The cells submitted where standard design production cells and
manufactured entirely in-house on its production line in
San Jose. CA. February 2011 Solar Junction
reached a 41.4% efficiency on a production
cell again validated by NREL. The cell
submitted for testing was also a standard
commercial-ready production cell. It is
significant because it was not a champion
cell gain but a product that could be
introduced straight into a customer's line.
In April 2011 Solar Junction broke the
World Record in cell efficiency. At 43.5%
efficiency Solar Junction has retained the
world record for the past year and continues
to strive to make additional technology
improvements to reach higher efficiency percentages.
The cell tested by NREL was once again a standard
5.5mm x 5.5mm production cell.
44 www.solar-international.net I Issue IX 2012